5320 lines
174 KiB
C
5320 lines
174 KiB
C
/* Target-struct-independent code to start (run) and stop an inferior
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process.
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Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
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1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
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2008 Free Software Foundation, Inc.
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||
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This file is part of GDB.
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||
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This program is free software; you can redistribute it and/or modify
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||
it under the terms of the GNU General Public License as published by
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||
the Free Software Foundation; either version 3 of the License, or
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||
(at your option) any later version.
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||
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||
This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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||
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You should have received a copy of the GNU General Public License
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||
along with this program. If not, see <http://www.gnu.org/licenses/>. */
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#include "defs.h"
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#include "gdb_string.h"
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#include <ctype.h>
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#include "symtab.h"
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#include "frame.h"
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#include "inferior.h"
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#include "exceptions.h"
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#include "breakpoint.h"
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#include "gdb_wait.h"
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#include "gdbcore.h"
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#include "gdbcmd.h"
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#include "cli/cli-script.h"
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#include "target.h"
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#include "gdbthread.h"
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#include "annotate.h"
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#include "symfile.h"
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#include "top.h"
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#include <signal.h>
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#include "inf-loop.h"
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#include "regcache.h"
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#include "value.h"
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#include "observer.h"
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#include "language.h"
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#include "solib.h"
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#include "main.h"
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#include "gdb_assert.h"
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#include "mi/mi-common.h"
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#include "event-top.h"
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/* Prototypes for local functions */
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static void signals_info (char *, int);
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static void handle_command (char *, int);
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static void sig_print_info (enum target_signal);
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static void sig_print_header (void);
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static void resume_cleanups (void *);
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static int hook_stop_stub (void *);
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static int restore_selected_frame (void *);
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static void build_infrun (void);
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static int follow_fork (void);
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static void set_schedlock_func (char *args, int from_tty,
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struct cmd_list_element *c);
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static int currently_stepping (struct thread_info *tp);
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static void xdb_handle_command (char *args, int from_tty);
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static int prepare_to_proceed (int);
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void _initialize_infrun (void);
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/* When set, stop the 'step' command if we enter a function which has
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no line number information. The normal behavior is that we step
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over such function. */
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int step_stop_if_no_debug = 0;
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static void
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show_step_stop_if_no_debug (struct ui_file *file, int from_tty,
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struct cmd_list_element *c, const char *value)
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{
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fprintf_filtered (file, _("Mode of the step operation is %s.\n"), value);
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}
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/* In asynchronous mode, but simulating synchronous execution. */
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int sync_execution = 0;
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/* wait_for_inferior and normal_stop use this to notify the user
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when the inferior stopped in a different thread than it had been
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running in. */
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static ptid_t previous_inferior_ptid;
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int debug_displaced = 0;
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static void
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show_debug_displaced (struct ui_file *file, int from_tty,
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struct cmd_list_element *c, const char *value)
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{
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fprintf_filtered (file, _("Displace stepping debugging is %s.\n"), value);
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}
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static int debug_infrun = 0;
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static void
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show_debug_infrun (struct ui_file *file, int from_tty,
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struct cmd_list_element *c, const char *value)
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{
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fprintf_filtered (file, _("Inferior debugging is %s.\n"), value);
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}
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/* If the program uses ELF-style shared libraries, then calls to
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functions in shared libraries go through stubs, which live in a
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table called the PLT (Procedure Linkage Table). The first time the
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function is called, the stub sends control to the dynamic linker,
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which looks up the function's real address, patches the stub so
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that future calls will go directly to the function, and then passes
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control to the function.
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If we are stepping at the source level, we don't want to see any of
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this --- we just want to skip over the stub and the dynamic linker.
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The simple approach is to single-step until control leaves the
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dynamic linker.
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However, on some systems (e.g., Red Hat's 5.2 distribution) the
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dynamic linker calls functions in the shared C library, so you
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can't tell from the PC alone whether the dynamic linker is still
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running. In this case, we use a step-resume breakpoint to get us
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past the dynamic linker, as if we were using "next" to step over a
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function call.
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in_solib_dynsym_resolve_code() says whether we're in the dynamic
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linker code or not. Normally, this means we single-step. However,
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if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
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address where we can place a step-resume breakpoint to get past the
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linker's symbol resolution function.
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in_solib_dynsym_resolve_code() can generally be implemented in a
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pretty portable way, by comparing the PC against the address ranges
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of the dynamic linker's sections.
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SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
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it depends on internal details of the dynamic linker. It's usually
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not too hard to figure out where to put a breakpoint, but it
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certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of
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sanity checking. If it can't figure things out, returning zero and
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getting the (possibly confusing) stepping behavior is better than
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signalling an error, which will obscure the change in the
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inferior's state. */
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/* This function returns TRUE if pc is the address of an instruction
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that lies within the dynamic linker (such as the event hook, or the
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dld itself).
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This function must be used only when a dynamic linker event has
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been caught, and the inferior is being stepped out of the hook, or
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undefined results are guaranteed. */
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#ifndef SOLIB_IN_DYNAMIC_LINKER
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#define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
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#endif
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/* Convert the #defines into values. This is temporary until wfi control
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flow is completely sorted out. */
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#ifndef CANNOT_STEP_HW_WATCHPOINTS
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#define CANNOT_STEP_HW_WATCHPOINTS 0
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#else
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#undef CANNOT_STEP_HW_WATCHPOINTS
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#define CANNOT_STEP_HW_WATCHPOINTS 1
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#endif
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/* Tables of how to react to signals; the user sets them. */
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static unsigned char *signal_stop;
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static unsigned char *signal_print;
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static unsigned char *signal_program;
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#define SET_SIGS(nsigs,sigs,flags) \
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do { \
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int signum = (nsigs); \
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while (signum-- > 0) \
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if ((sigs)[signum]) \
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(flags)[signum] = 1; \
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} while (0)
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#define UNSET_SIGS(nsigs,sigs,flags) \
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do { \
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int signum = (nsigs); \
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while (signum-- > 0) \
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if ((sigs)[signum]) \
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(flags)[signum] = 0; \
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} while (0)
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/* Value to pass to target_resume() to cause all threads to resume */
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#define RESUME_ALL (pid_to_ptid (-1))
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/* Command list pointer for the "stop" placeholder. */
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static struct cmd_list_element *stop_command;
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/* Function inferior was in as of last step command. */
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static struct symbol *step_start_function;
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/* Nonzero if we want to give control to the user when we're notified
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of shared library events by the dynamic linker. */
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static int stop_on_solib_events;
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static void
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show_stop_on_solib_events (struct ui_file *file, int from_tty,
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struct cmd_list_element *c, const char *value)
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{
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fprintf_filtered (file, _("Stopping for shared library events is %s.\n"),
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value);
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}
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/* Nonzero means expecting a trace trap
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and should stop the inferior and return silently when it happens. */
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int stop_after_trap;
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/* Save register contents here when about to pop a stack dummy frame,
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if-and-only-if proceed_to_finish is set.
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Thus this contains the return value from the called function (assuming
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values are returned in a register). */
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struct regcache *stop_registers;
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/* Nonzero after stop if current stack frame should be printed. */
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static int stop_print_frame;
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/* This is a cached copy of the pid/waitstatus of the last event
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returned by target_wait()/deprecated_target_wait_hook(). This
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information is returned by get_last_target_status(). */
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static ptid_t target_last_wait_ptid;
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static struct target_waitstatus target_last_waitstatus;
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static void context_switch (ptid_t ptid);
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void init_thread_stepping_state (struct thread_info *tss);
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void init_infwait_state (void);
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/* This is used to remember when a fork, vfork or exec event
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was caught by a catchpoint, and thus the event is to be
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followed at the next resume of the inferior, and not
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immediately. */
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static struct
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{
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enum target_waitkind kind;
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struct
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{
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ptid_t parent_pid;
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ptid_t child_pid;
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}
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fork_event;
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char *execd_pathname;
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}
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pending_follow;
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static const char follow_fork_mode_child[] = "child";
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static const char follow_fork_mode_parent[] = "parent";
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static const char *follow_fork_mode_kind_names[] = {
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follow_fork_mode_child,
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follow_fork_mode_parent,
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NULL
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};
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static const char *follow_fork_mode_string = follow_fork_mode_parent;
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static void
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show_follow_fork_mode_string (struct ui_file *file, int from_tty,
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struct cmd_list_element *c, const char *value)
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{
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fprintf_filtered (file, _("\
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Debugger response to a program call of fork or vfork is \"%s\".\n"),
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value);
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}
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static int
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follow_fork (void)
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{
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int follow_child = (follow_fork_mode_string == follow_fork_mode_child);
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return target_follow_fork (follow_child);
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}
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void
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follow_inferior_reset_breakpoints (void)
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{
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struct thread_info *tp = inferior_thread ();
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/* Was there a step_resume breakpoint? (There was if the user
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did a "next" at the fork() call.) If so, explicitly reset its
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thread number.
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step_resumes are a form of bp that are made to be per-thread.
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Since we created the step_resume bp when the parent process
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was being debugged, and now are switching to the child process,
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from the breakpoint package's viewpoint, that's a switch of
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"threads". We must update the bp's notion of which thread
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it is for, or it'll be ignored when it triggers. */
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if (tp->step_resume_breakpoint)
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breakpoint_re_set_thread (tp->step_resume_breakpoint);
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/* Reinsert all breakpoints in the child. The user may have set
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breakpoints after catching the fork, in which case those
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were never set in the child, but only in the parent. This makes
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sure the inserted breakpoints match the breakpoint list. */
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breakpoint_re_set ();
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insert_breakpoints ();
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}
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/* EXECD_PATHNAME is assumed to be non-NULL. */
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static void
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follow_exec (ptid_t pid, char *execd_pathname)
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{
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struct target_ops *tgt;
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struct thread_info *th = inferior_thread ();
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/* This is an exec event that we actually wish to pay attention to.
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Refresh our symbol table to the newly exec'd program, remove any
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momentary bp's, etc.
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If there are breakpoints, they aren't really inserted now,
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since the exec() transformed our inferior into a fresh set
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of instructions.
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We want to preserve symbolic breakpoints on the list, since
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we have hopes that they can be reset after the new a.out's
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symbol table is read.
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However, any "raw" breakpoints must be removed from the list
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(e.g., the solib bp's), since their address is probably invalid
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now.
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And, we DON'T want to call delete_breakpoints() here, since
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that may write the bp's "shadow contents" (the instruction
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value that was overwritten witha TRAP instruction). Since
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we now have a new a.out, those shadow contents aren't valid. */
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update_breakpoints_after_exec ();
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/* If there was one, it's gone now. We cannot truly step-to-next
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statement through an exec(). */
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th->step_resume_breakpoint = NULL;
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th->step_range_start = 0;
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th->step_range_end = 0;
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/* What is this a.out's name? */
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printf_unfiltered (_("Executing new program: %s\n"), execd_pathname);
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/* We've followed the inferior through an exec. Therefore, the
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inferior has essentially been killed & reborn. */
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gdb_flush (gdb_stdout);
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breakpoint_init_inferior (inf_execd);
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if (gdb_sysroot && *gdb_sysroot)
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{
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char *name = alloca (strlen (gdb_sysroot)
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+ strlen (execd_pathname)
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+ 1);
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strcpy (name, gdb_sysroot);
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strcat (name, execd_pathname);
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execd_pathname = name;
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}
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/* That a.out is now the one to use. */
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exec_file_attach (execd_pathname, 0);
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/* Reset the shared library package. This ensures that we get a
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shlib event when the child reaches "_start", at which point the
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dld will have had a chance to initialize the child. */
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/* Also, loading a symbol file below may trigger symbol lookups, and
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we don't want those to be satisfied by the libraries of the
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previous incarnation of this process. */
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no_shared_libraries (NULL, 0);
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/* Load the main file's symbols. */
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symbol_file_add_main (execd_pathname, 0);
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#ifdef SOLIB_CREATE_INFERIOR_HOOK
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SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid));
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#else
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solib_create_inferior_hook ();
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#endif
|
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||
/* Reinsert all breakpoints. (Those which were symbolic have
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been reset to the proper address in the new a.out, thanks
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to symbol_file_command...) */
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insert_breakpoints ();
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||
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/* The next resume of this inferior should bring it to the shlib
|
||
startup breakpoints. (If the user had also set bp's on
|
||
"main" from the old (parent) process, then they'll auto-
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||
matically get reset there in the new process.) */
|
||
}
|
||
|
||
/* Non-zero if we just simulating a single-step. This is needed
|
||
because we cannot remove the breakpoints in the inferior process
|
||
until after the `wait' in `wait_for_inferior'. */
|
||
static int singlestep_breakpoints_inserted_p = 0;
|
||
|
||
/* The thread we inserted single-step breakpoints for. */
|
||
static ptid_t singlestep_ptid;
|
||
|
||
/* PC when we started this single-step. */
|
||
static CORE_ADDR singlestep_pc;
|
||
|
||
/* If another thread hit the singlestep breakpoint, we save the original
|
||
thread here so that we can resume single-stepping it later. */
|
||
static ptid_t saved_singlestep_ptid;
|
||
static int stepping_past_singlestep_breakpoint;
|
||
|
||
/* If not equal to null_ptid, this means that after stepping over breakpoint
|
||
is finished, we need to switch to deferred_step_ptid, and step it.
|
||
|
||
The use case is when one thread has hit a breakpoint, and then the user
|
||
has switched to another thread and issued 'step'. We need to step over
|
||
breakpoint in the thread which hit the breakpoint, but then continue
|
||
stepping the thread user has selected. */
|
||
static ptid_t deferred_step_ptid;
|
||
|
||
/* Displaced stepping. */
|
||
|
||
/* In non-stop debugging mode, we must take special care to manage
|
||
breakpoints properly; in particular, the traditional strategy for
|
||
stepping a thread past a breakpoint it has hit is unsuitable.
|
||
'Displaced stepping' is a tactic for stepping one thread past a
|
||
breakpoint it has hit while ensuring that other threads running
|
||
concurrently will hit the breakpoint as they should.
|
||
|
||
The traditional way to step a thread T off a breakpoint in a
|
||
multi-threaded program in all-stop mode is as follows:
|
||
|
||
a0) Initially, all threads are stopped, and breakpoints are not
|
||
inserted.
|
||
a1) We single-step T, leaving breakpoints uninserted.
|
||
a2) We insert breakpoints, and resume all threads.
|
||
|
||
In non-stop debugging, however, this strategy is unsuitable: we
|
||
don't want to have to stop all threads in the system in order to
|
||
continue or step T past a breakpoint. Instead, we use displaced
|
||
stepping:
|
||
|
||
n0) Initially, T is stopped, other threads are running, and
|
||
breakpoints are inserted.
|
||
n1) We copy the instruction "under" the breakpoint to a separate
|
||
location, outside the main code stream, making any adjustments
|
||
to the instruction, register, and memory state as directed by
|
||
T's architecture.
|
||
n2) We single-step T over the instruction at its new location.
|
||
n3) We adjust the resulting register and memory state as directed
|
||
by T's architecture. This includes resetting T's PC to point
|
||
back into the main instruction stream.
|
||
n4) We resume T.
|
||
|
||
This approach depends on the following gdbarch methods:
|
||
|
||
- gdbarch_max_insn_length and gdbarch_displaced_step_location
|
||
indicate where to copy the instruction, and how much space must
|
||
be reserved there. We use these in step n1.
|
||
|
||
- gdbarch_displaced_step_copy_insn copies a instruction to a new
|
||
address, and makes any necessary adjustments to the instruction,
|
||
register contents, and memory. We use this in step n1.
|
||
|
||
- gdbarch_displaced_step_fixup adjusts registers and memory after
|
||
we have successfuly single-stepped the instruction, to yield the
|
||
same effect the instruction would have had if we had executed it
|
||
at its original address. We use this in step n3.
|
||
|
||
- gdbarch_displaced_step_free_closure provides cleanup.
|
||
|
||
The gdbarch_displaced_step_copy_insn and
|
||
gdbarch_displaced_step_fixup functions must be written so that
|
||
copying an instruction with gdbarch_displaced_step_copy_insn,
|
||
single-stepping across the copied instruction, and then applying
|
||
gdbarch_displaced_insn_fixup should have the same effects on the
|
||
thread's memory and registers as stepping the instruction in place
|
||
would have. Exactly which responsibilities fall to the copy and
|
||
which fall to the fixup is up to the author of those functions.
|
||
|
||
See the comments in gdbarch.sh for details.
|
||
|
||
Note that displaced stepping and software single-step cannot
|
||
currently be used in combination, although with some care I think
|
||
they could be made to. Software single-step works by placing
|
||
breakpoints on all possible subsequent instructions; if the
|
||
displaced instruction is a PC-relative jump, those breakpoints
|
||
could fall in very strange places --- on pages that aren't
|
||
executable, or at addresses that are not proper instruction
|
||
boundaries. (We do generally let other threads run while we wait
|
||
to hit the software single-step breakpoint, and they might
|
||
encounter such a corrupted instruction.) One way to work around
|
||
this would be to have gdbarch_displaced_step_copy_insn fully
|
||
simulate the effect of PC-relative instructions (and return NULL)
|
||
on architectures that use software single-stepping.
|
||
|
||
In non-stop mode, we can have independent and simultaneous step
|
||
requests, so more than one thread may need to simultaneously step
|
||
over a breakpoint. The current implementation assumes there is
|
||
only one scratch space per process. In this case, we have to
|
||
serialize access to the scratch space. If thread A wants to step
|
||
over a breakpoint, but we are currently waiting for some other
|
||
thread to complete a displaced step, we leave thread A stopped and
|
||
place it in the displaced_step_request_queue. Whenever a displaced
|
||
step finishes, we pick the next thread in the queue and start a new
|
||
displaced step operation on it. See displaced_step_prepare and
|
||
displaced_step_fixup for details. */
|
||
|
||
/* If this is not null_ptid, this is the thread carrying out a
|
||
displaced single-step. This thread's state will require fixing up
|
||
once it has completed its step. */
|
||
static ptid_t displaced_step_ptid;
|
||
|
||
struct displaced_step_request
|
||
{
|
||
ptid_t ptid;
|
||
struct displaced_step_request *next;
|
||
};
|
||
|
||
/* A queue of pending displaced stepping requests. */
|
||
struct displaced_step_request *displaced_step_request_queue;
|
||
|
||
/* The architecture the thread had when we stepped it. */
|
||
static struct gdbarch *displaced_step_gdbarch;
|
||
|
||
/* The closure provided gdbarch_displaced_step_copy_insn, to be used
|
||
for post-step cleanup. */
|
||
static struct displaced_step_closure *displaced_step_closure;
|
||
|
||
/* The address of the original instruction, and the copy we made. */
|
||
static CORE_ADDR displaced_step_original, displaced_step_copy;
|
||
|
||
/* Saved contents of copy area. */
|
||
static gdb_byte *displaced_step_saved_copy;
|
||
|
||
/* Enum strings for "set|show displaced-stepping". */
|
||
|
||
static const char can_use_displaced_stepping_auto[] = "auto";
|
||
static const char can_use_displaced_stepping_on[] = "on";
|
||
static const char can_use_displaced_stepping_off[] = "off";
|
||
static const char *can_use_displaced_stepping_enum[] =
|
||
{
|
||
can_use_displaced_stepping_auto,
|
||
can_use_displaced_stepping_on,
|
||
can_use_displaced_stepping_off,
|
||
NULL,
|
||
};
|
||
|
||
/* If ON, and the architecture supports it, GDB will use displaced
|
||
stepping to step over breakpoints. If OFF, or if the architecture
|
||
doesn't support it, GDB will instead use the traditional
|
||
hold-and-step approach. If AUTO (which is the default), GDB will
|
||
decide which technique to use to step over breakpoints depending on
|
||
which of all-stop or non-stop mode is active --- displaced stepping
|
||
in non-stop mode; hold-and-step in all-stop mode. */
|
||
|
||
static const char *can_use_displaced_stepping =
|
||
can_use_displaced_stepping_auto;
|
||
|
||
static void
|
||
show_can_use_displaced_stepping (struct ui_file *file, int from_tty,
|
||
struct cmd_list_element *c,
|
||
const char *value)
|
||
{
|
||
if (can_use_displaced_stepping == can_use_displaced_stepping_auto)
|
||
fprintf_filtered (file, _("\
|
||
Debugger's willingness to use displaced stepping to step over \
|
||
breakpoints is %s (currently %s).\n"),
|
||
value, non_stop ? "on" : "off");
|
||
else
|
||
fprintf_filtered (file, _("\
|
||
Debugger's willingness to use displaced stepping to step over \
|
||
breakpoints is %s.\n"), value);
|
||
}
|
||
|
||
/* Return non-zero if displaced stepping can/should be used to step
|
||
over breakpoints. */
|
||
|
||
static int
|
||
use_displaced_stepping (struct gdbarch *gdbarch)
|
||
{
|
||
return (((can_use_displaced_stepping == can_use_displaced_stepping_auto
|
||
&& non_stop)
|
||
|| can_use_displaced_stepping == can_use_displaced_stepping_on)
|
||
&& gdbarch_displaced_step_copy_insn_p (gdbarch));
|
||
}
|
||
|
||
/* Clean out any stray displaced stepping state. */
|
||
static void
|
||
displaced_step_clear (void)
|
||
{
|
||
/* Indicate that there is no cleanup pending. */
|
||
displaced_step_ptid = null_ptid;
|
||
|
||
if (displaced_step_closure)
|
||
{
|
||
gdbarch_displaced_step_free_closure (displaced_step_gdbarch,
|
||
displaced_step_closure);
|
||
displaced_step_closure = NULL;
|
||
}
|
||
}
|
||
|
||
static void
|
||
cleanup_displaced_step_closure (void *ptr)
|
||
{
|
||
struct displaced_step_closure *closure = ptr;
|
||
|
||
gdbarch_displaced_step_free_closure (current_gdbarch, closure);
|
||
}
|
||
|
||
/* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
|
||
void
|
||
displaced_step_dump_bytes (struct ui_file *file,
|
||
const gdb_byte *buf,
|
||
size_t len)
|
||
{
|
||
int i;
|
||
|
||
for (i = 0; i < len; i++)
|
||
fprintf_unfiltered (file, "%02x ", buf[i]);
|
||
fputs_unfiltered ("\n", file);
|
||
}
|
||
|
||
/* Prepare to single-step, using displaced stepping.
|
||
|
||
Note that we cannot use displaced stepping when we have a signal to
|
||
deliver. If we have a signal to deliver and an instruction to step
|
||
over, then after the step, there will be no indication from the
|
||
target whether the thread entered a signal handler or ignored the
|
||
signal and stepped over the instruction successfully --- both cases
|
||
result in a simple SIGTRAP. In the first case we mustn't do a
|
||
fixup, and in the second case we must --- but we can't tell which.
|
||
Comments in the code for 'random signals' in handle_inferior_event
|
||
explain how we handle this case instead.
|
||
|
||
Returns 1 if preparing was successful -- this thread is going to be
|
||
stepped now; or 0 if displaced stepping this thread got queued. */
|
||
static int
|
||
displaced_step_prepare (ptid_t ptid)
|
||
{
|
||
struct cleanup *old_cleanups, *ignore_cleanups;
|
||
struct regcache *regcache = get_thread_regcache (ptid);
|
||
struct gdbarch *gdbarch = get_regcache_arch (regcache);
|
||
CORE_ADDR original, copy;
|
||
ULONGEST len;
|
||
struct displaced_step_closure *closure;
|
||
|
||
/* We should never reach this function if the architecture does not
|
||
support displaced stepping. */
|
||
gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch));
|
||
|
||
/* For the first cut, we're displaced stepping one thread at a
|
||
time. */
|
||
|
||
if (!ptid_equal (displaced_step_ptid, null_ptid))
|
||
{
|
||
/* Already waiting for a displaced step to finish. Defer this
|
||
request and place in queue. */
|
||
struct displaced_step_request *req, *new_req;
|
||
|
||
if (debug_displaced)
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"displaced: defering step of %s\n",
|
||
target_pid_to_str (ptid));
|
||
|
||
new_req = xmalloc (sizeof (*new_req));
|
||
new_req->ptid = ptid;
|
||
new_req->next = NULL;
|
||
|
||
if (displaced_step_request_queue)
|
||
{
|
||
for (req = displaced_step_request_queue;
|
||
req && req->next;
|
||
req = req->next)
|
||
;
|
||
req->next = new_req;
|
||
}
|
||
else
|
||
displaced_step_request_queue = new_req;
|
||
|
||
return 0;
|
||
}
|
||
else
|
||
{
|
||
if (debug_displaced)
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"displaced: stepping %s now\n",
|
||
target_pid_to_str (ptid));
|
||
}
|
||
|
||
displaced_step_clear ();
|
||
|
||
old_cleanups = save_inferior_ptid ();
|
||
inferior_ptid = ptid;
|
||
|
||
original = regcache_read_pc (regcache);
|
||
|
||
copy = gdbarch_displaced_step_location (gdbarch);
|
||
len = gdbarch_max_insn_length (gdbarch);
|
||
|
||
/* Save the original contents of the copy area. */
|
||
displaced_step_saved_copy = xmalloc (len);
|
||
ignore_cleanups = make_cleanup (free_current_contents,
|
||
&displaced_step_saved_copy);
|
||
read_memory (copy, displaced_step_saved_copy, len);
|
||
if (debug_displaced)
|
||
{
|
||
fprintf_unfiltered (gdb_stdlog, "displaced: saved 0x%s: ",
|
||
paddr_nz (copy));
|
||
displaced_step_dump_bytes (gdb_stdlog, displaced_step_saved_copy, len);
|
||
};
|
||
|
||
closure = gdbarch_displaced_step_copy_insn (gdbarch,
|
||
original, copy, regcache);
|
||
|
||
/* We don't support the fully-simulated case at present. */
|
||
gdb_assert (closure);
|
||
|
||
make_cleanup (cleanup_displaced_step_closure, closure);
|
||
|
||
/* Resume execution at the copy. */
|
||
regcache_write_pc (regcache, copy);
|
||
|
||
discard_cleanups (ignore_cleanups);
|
||
|
||
do_cleanups (old_cleanups);
|
||
|
||
if (debug_displaced)
|
||
fprintf_unfiltered (gdb_stdlog, "displaced: displaced pc to 0x%s\n",
|
||
paddr_nz (copy));
|
||
|
||
/* Save the information we need to fix things up if the step
|
||
succeeds. */
|
||
displaced_step_ptid = ptid;
|
||
displaced_step_gdbarch = gdbarch;
|
||
displaced_step_closure = closure;
|
||
displaced_step_original = original;
|
||
displaced_step_copy = copy;
|
||
return 1;
|
||
}
|
||
|
||
static void
|
||
displaced_step_clear_cleanup (void *ignore)
|
||
{
|
||
displaced_step_clear ();
|
||
}
|
||
|
||
static void
|
||
write_memory_ptid (ptid_t ptid, CORE_ADDR memaddr, const gdb_byte *myaddr, int len)
|
||
{
|
||
struct cleanup *ptid_cleanup = save_inferior_ptid ();
|
||
inferior_ptid = ptid;
|
||
write_memory (memaddr, myaddr, len);
|
||
do_cleanups (ptid_cleanup);
|
||
}
|
||
|
||
static void
|
||
displaced_step_fixup (ptid_t event_ptid, enum target_signal signal)
|
||
{
|
||
struct cleanup *old_cleanups;
|
||
|
||
/* Was this event for the pid we displaced? */
|
||
if (ptid_equal (displaced_step_ptid, null_ptid)
|
||
|| ! ptid_equal (displaced_step_ptid, event_ptid))
|
||
return;
|
||
|
||
old_cleanups = make_cleanup (displaced_step_clear_cleanup, 0);
|
||
|
||
/* Restore the contents of the copy area. */
|
||
{
|
||
ULONGEST len = gdbarch_max_insn_length (displaced_step_gdbarch);
|
||
write_memory_ptid (displaced_step_ptid, displaced_step_copy,
|
||
displaced_step_saved_copy, len);
|
||
if (debug_displaced)
|
||
fprintf_unfiltered (gdb_stdlog, "displaced: restored 0x%s\n",
|
||
paddr_nz (displaced_step_copy));
|
||
}
|
||
|
||
/* Did the instruction complete successfully? */
|
||
if (signal == TARGET_SIGNAL_TRAP)
|
||
{
|
||
/* Fix up the resulting state. */
|
||
gdbarch_displaced_step_fixup (displaced_step_gdbarch,
|
||
displaced_step_closure,
|
||
displaced_step_original,
|
||
displaced_step_copy,
|
||
get_thread_regcache (displaced_step_ptid));
|
||
}
|
||
else
|
||
{
|
||
/* Since the instruction didn't complete, all we can do is
|
||
relocate the PC. */
|
||
struct regcache *regcache = get_thread_regcache (event_ptid);
|
||
CORE_ADDR pc = regcache_read_pc (regcache);
|
||
pc = displaced_step_original + (pc - displaced_step_copy);
|
||
regcache_write_pc (regcache, pc);
|
||
}
|
||
|
||
do_cleanups (old_cleanups);
|
||
|
||
displaced_step_ptid = null_ptid;
|
||
|
||
/* Are there any pending displaced stepping requests? If so, run
|
||
one now. */
|
||
while (displaced_step_request_queue)
|
||
{
|
||
struct displaced_step_request *head;
|
||
ptid_t ptid;
|
||
CORE_ADDR actual_pc;
|
||
|
||
head = displaced_step_request_queue;
|
||
ptid = head->ptid;
|
||
displaced_step_request_queue = head->next;
|
||
xfree (head);
|
||
|
||
context_switch (ptid);
|
||
|
||
actual_pc = read_pc ();
|
||
|
||
if (breakpoint_here_p (actual_pc))
|
||
{
|
||
if (debug_displaced)
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"displaced: stepping queued %s now\n",
|
||
target_pid_to_str (ptid));
|
||
|
||
displaced_step_prepare (ptid);
|
||
|
||
if (debug_displaced)
|
||
{
|
||
gdb_byte buf[4];
|
||
|
||
fprintf_unfiltered (gdb_stdlog, "displaced: run 0x%s: ",
|
||
paddr_nz (actual_pc));
|
||
read_memory (actual_pc, buf, sizeof (buf));
|
||
displaced_step_dump_bytes (gdb_stdlog, buf, sizeof (buf));
|
||
}
|
||
|
||
target_resume (ptid, 1, TARGET_SIGNAL_0);
|
||
|
||
/* Done, we're stepping a thread. */
|
||
break;
|
||
}
|
||
else
|
||
{
|
||
int step;
|
||
struct thread_info *tp = inferior_thread ();
|
||
|
||
/* The breakpoint we were sitting under has since been
|
||
removed. */
|
||
tp->trap_expected = 0;
|
||
|
||
/* Go back to what we were trying to do. */
|
||
step = currently_stepping (tp);
|
||
|
||
if (debug_displaced)
|
||
fprintf_unfiltered (gdb_stdlog, "breakpoint is gone %s: step(%d)\n",
|
||
target_pid_to_str (tp->ptid), step);
|
||
|
||
target_resume (ptid, step, TARGET_SIGNAL_0);
|
||
tp->stop_signal = TARGET_SIGNAL_0;
|
||
|
||
/* This request was discarded. See if there's any other
|
||
thread waiting for its turn. */
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Update global variables holding ptids to hold NEW_PTID if they were
|
||
holding OLD_PTID. */
|
||
static void
|
||
infrun_thread_ptid_changed (ptid_t old_ptid, ptid_t new_ptid)
|
||
{
|
||
struct displaced_step_request *it;
|
||
|
||
if (ptid_equal (inferior_ptid, old_ptid))
|
||
inferior_ptid = new_ptid;
|
||
|
||
if (ptid_equal (singlestep_ptid, old_ptid))
|
||
singlestep_ptid = new_ptid;
|
||
|
||
if (ptid_equal (displaced_step_ptid, old_ptid))
|
||
displaced_step_ptid = new_ptid;
|
||
|
||
if (ptid_equal (deferred_step_ptid, old_ptid))
|
||
deferred_step_ptid = new_ptid;
|
||
|
||
for (it = displaced_step_request_queue; it; it = it->next)
|
||
if (ptid_equal (it->ptid, old_ptid))
|
||
it->ptid = new_ptid;
|
||
}
|
||
|
||
|
||
/* Resuming. */
|
||
|
||
/* Things to clean up if we QUIT out of resume (). */
|
||
static void
|
||
resume_cleanups (void *ignore)
|
||
{
|
||
normal_stop ();
|
||
}
|
||
|
||
static const char schedlock_off[] = "off";
|
||
static const char schedlock_on[] = "on";
|
||
static const char schedlock_step[] = "step";
|
||
static const char *scheduler_enums[] = {
|
||
schedlock_off,
|
||
schedlock_on,
|
||
schedlock_step,
|
||
NULL
|
||
};
|
||
static const char *scheduler_mode = schedlock_off;
|
||
static void
|
||
show_scheduler_mode (struct ui_file *file, int from_tty,
|
||
struct cmd_list_element *c, const char *value)
|
||
{
|
||
fprintf_filtered (file, _("\
|
||
Mode for locking scheduler during execution is \"%s\".\n"),
|
||
value);
|
||
}
|
||
|
||
static void
|
||
set_schedlock_func (char *args, int from_tty, struct cmd_list_element *c)
|
||
{
|
||
if (!target_can_lock_scheduler)
|
||
{
|
||
scheduler_mode = schedlock_off;
|
||
error (_("Target '%s' cannot support this command."), target_shortname);
|
||
}
|
||
}
|
||
|
||
|
||
/* Resume the inferior, but allow a QUIT. This is useful if the user
|
||
wants to interrupt some lengthy single-stepping operation
|
||
(for child processes, the SIGINT goes to the inferior, and so
|
||
we get a SIGINT random_signal, but for remote debugging and perhaps
|
||
other targets, that's not true).
|
||
|
||
STEP nonzero if we should step (zero to continue instead).
|
||
SIG is the signal to give the inferior (zero for none). */
|
||
void
|
||
resume (int step, enum target_signal sig)
|
||
{
|
||
int should_resume = 1;
|
||
struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
|
||
struct regcache *regcache = get_current_regcache ();
|
||
struct gdbarch *gdbarch = get_regcache_arch (regcache);
|
||
struct thread_info *tp = inferior_thread ();
|
||
CORE_ADDR pc = regcache_read_pc (regcache);
|
||
QUIT;
|
||
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"infrun: resume (step=%d, signal=%d), "
|
||
"trap_expected=%d\n",
|
||
step, sig, tp->trap_expected);
|
||
|
||
/* Some targets (e.g. Solaris x86) have a kernel bug when stepping
|
||
over an instruction that causes a page fault without triggering
|
||
a hardware watchpoint. The kernel properly notices that it shouldn't
|
||
stop, because the hardware watchpoint is not triggered, but it forgets
|
||
the step request and continues the program normally.
|
||
Work around the problem by removing hardware watchpoints if a step is
|
||
requested, GDB will check for a hardware watchpoint trigger after the
|
||
step anyway. */
|
||
if (CANNOT_STEP_HW_WATCHPOINTS && step)
|
||
remove_hw_watchpoints ();
|
||
|
||
|
||
/* Normally, by the time we reach `resume', the breakpoints are either
|
||
removed or inserted, as appropriate. The exception is if we're sitting
|
||
at a permanent breakpoint; we need to step over it, but permanent
|
||
breakpoints can't be removed. So we have to test for it here. */
|
||
if (breakpoint_here_p (pc) == permanent_breakpoint_here)
|
||
{
|
||
if (gdbarch_skip_permanent_breakpoint_p (gdbarch))
|
||
gdbarch_skip_permanent_breakpoint (gdbarch, regcache);
|
||
else
|
||
error (_("\
|
||
The program is stopped at a permanent breakpoint, but GDB does not know\n\
|
||
how to step past a permanent breakpoint on this architecture. Try using\n\
|
||
a command like `return' or `jump' to continue execution."));
|
||
}
|
||
|
||
/* If enabled, step over breakpoints by executing a copy of the
|
||
instruction at a different address.
|
||
|
||
We can't use displaced stepping when we have a signal to deliver;
|
||
the comments for displaced_step_prepare explain why. The
|
||
comments in the handle_inferior event for dealing with 'random
|
||
signals' explain what we do instead. */
|
||
if (use_displaced_stepping (gdbarch)
|
||
&& tp->trap_expected
|
||
&& sig == TARGET_SIGNAL_0)
|
||
{
|
||
if (!displaced_step_prepare (inferior_ptid))
|
||
{
|
||
/* Got placed in displaced stepping queue. Will be resumed
|
||
later when all the currently queued displaced stepping
|
||
requests finish. The thread is not executing at this point,
|
||
and the call to set_executing will be made later. But we
|
||
need to call set_running here, since from frontend point of view,
|
||
the thread is running. */
|
||
set_running (inferior_ptid, 1);
|
||
discard_cleanups (old_cleanups);
|
||
return;
|
||
}
|
||
}
|
||
|
||
if (step && gdbarch_software_single_step_p (gdbarch))
|
||
{
|
||
/* Do it the hard way, w/temp breakpoints */
|
||
if (gdbarch_software_single_step (gdbarch, get_current_frame ()))
|
||
{
|
||
/* ...and don't ask hardware to do it. */
|
||
step = 0;
|
||
/* and do not pull these breakpoints until after a `wait' in
|
||
`wait_for_inferior' */
|
||
singlestep_breakpoints_inserted_p = 1;
|
||
singlestep_ptid = inferior_ptid;
|
||
singlestep_pc = pc;
|
||
}
|
||
}
|
||
|
||
/* If there were any forks/vforks/execs that were caught and are
|
||
now to be followed, then do so. */
|
||
switch (pending_follow.kind)
|
||
{
|
||
case TARGET_WAITKIND_FORKED:
|
||
case TARGET_WAITKIND_VFORKED:
|
||
pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
|
||
if (follow_fork ())
|
||
should_resume = 0;
|
||
break;
|
||
|
||
case TARGET_WAITKIND_EXECD:
|
||
/* follow_exec is called as soon as the exec event is seen. */
|
||
pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
|
||
break;
|
||
|
||
default:
|
||
break;
|
||
}
|
||
|
||
/* Install inferior's terminal modes. */
|
||
target_terminal_inferior ();
|
||
|
||
if (should_resume)
|
||
{
|
||
ptid_t resume_ptid;
|
||
|
||
resume_ptid = RESUME_ALL; /* Default */
|
||
|
||
/* If STEP is set, it's a request to use hardware stepping
|
||
facilities. But in that case, we should never
|
||
use singlestep breakpoint. */
|
||
gdb_assert (!(singlestep_breakpoints_inserted_p && step));
|
||
|
||
if (singlestep_breakpoints_inserted_p
|
||
&& stepping_past_singlestep_breakpoint)
|
||
{
|
||
/* The situation here is as follows. In thread T1 we wanted to
|
||
single-step. Lacking hardware single-stepping we've
|
||
set breakpoint at the PC of the next instruction -- call it
|
||
P. After resuming, we've hit that breakpoint in thread T2.
|
||
Now we've removed original breakpoint, inserted breakpoint
|
||
at P+1, and try to step to advance T2 past breakpoint.
|
||
We need to step only T2, as if T1 is allowed to freely run,
|
||
it can run past P, and if other threads are allowed to run,
|
||
they can hit breakpoint at P+1, and nested hits of single-step
|
||
breakpoints is not something we'd want -- that's complicated
|
||
to support, and has no value. */
|
||
resume_ptid = inferior_ptid;
|
||
}
|
||
|
||
if ((step || singlestep_breakpoints_inserted_p)
|
||
&& tp->trap_expected)
|
||
{
|
||
/* We're allowing a thread to run past a breakpoint it has
|
||
hit, by single-stepping the thread with the breakpoint
|
||
removed. In which case, we need to single-step only this
|
||
thread, and keep others stopped, as they can miss this
|
||
breakpoint if allowed to run.
|
||
|
||
The current code actually removes all breakpoints when
|
||
doing this, not just the one being stepped over, so if we
|
||
let other threads run, we can actually miss any
|
||
breakpoint, not just the one at PC. */
|
||
resume_ptid = inferior_ptid;
|
||
}
|
||
|
||
if (non_stop)
|
||
{
|
||
/* With non-stop mode on, threads are always handled
|
||
individually. */
|
||
resume_ptid = inferior_ptid;
|
||
}
|
||
else if ((scheduler_mode == schedlock_on)
|
||
|| (scheduler_mode == schedlock_step
|
||
&& (step || singlestep_breakpoints_inserted_p)))
|
||
{
|
||
/* User-settable 'scheduler' mode requires solo thread resume. */
|
||
resume_ptid = inferior_ptid;
|
||
}
|
||
|
||
if (gdbarch_cannot_step_breakpoint (gdbarch))
|
||
{
|
||
/* Most targets can step a breakpoint instruction, thus
|
||
executing it normally. But if this one cannot, just
|
||
continue and we will hit it anyway. */
|
||
if (step && breakpoint_inserted_here_p (pc))
|
||
step = 0;
|
||
}
|
||
|
||
if (debug_displaced
|
||
&& use_displaced_stepping (gdbarch)
|
||
&& tp->trap_expected)
|
||
{
|
||
struct regcache *resume_regcache = get_thread_regcache (resume_ptid);
|
||
CORE_ADDR actual_pc = regcache_read_pc (resume_regcache);
|
||
gdb_byte buf[4];
|
||
|
||
fprintf_unfiltered (gdb_stdlog, "displaced: run 0x%s: ",
|
||
paddr_nz (actual_pc));
|
||
read_memory (actual_pc, buf, sizeof (buf));
|
||
displaced_step_dump_bytes (gdb_stdlog, buf, sizeof (buf));
|
||
}
|
||
|
||
target_resume (resume_ptid, step, sig);
|
||
|
||
/* Avoid confusing the next resume, if the next stop/resume
|
||
happens to apply to another thread. */
|
||
tp->stop_signal = TARGET_SIGNAL_0;
|
||
}
|
||
|
||
discard_cleanups (old_cleanups);
|
||
}
|
||
|
||
/* Proceeding. */
|
||
|
||
/* Clear out all variables saying what to do when inferior is continued.
|
||
First do this, then set the ones you want, then call `proceed'. */
|
||
|
||
void
|
||
clear_proceed_status (void)
|
||
{
|
||
if (!ptid_equal (inferior_ptid, null_ptid))
|
||
{
|
||
struct thread_info *tp;
|
||
struct inferior *inferior;
|
||
|
||
tp = inferior_thread ();
|
||
|
||
tp->trap_expected = 0;
|
||
tp->step_range_start = 0;
|
||
tp->step_range_end = 0;
|
||
tp->step_frame_id = null_frame_id;
|
||
tp->step_over_calls = STEP_OVER_UNDEBUGGABLE;
|
||
tp->stop_requested = 0;
|
||
|
||
tp->stop_step = 0;
|
||
|
||
tp->proceed_to_finish = 0;
|
||
|
||
/* Discard any remaining commands or status from previous
|
||
stop. */
|
||
bpstat_clear (&tp->stop_bpstat);
|
||
|
||
inferior = current_inferior ();
|
||
inferior->stop_soon = NO_STOP_QUIETLY;
|
||
}
|
||
|
||
stop_after_trap = 0;
|
||
breakpoint_proceeded = 1; /* We're about to proceed... */
|
||
|
||
if (stop_registers)
|
||
{
|
||
regcache_xfree (stop_registers);
|
||
stop_registers = NULL;
|
||
}
|
||
}
|
||
|
||
/* This should be suitable for any targets that support threads. */
|
||
|
||
static int
|
||
prepare_to_proceed (int step)
|
||
{
|
||
ptid_t wait_ptid;
|
||
struct target_waitstatus wait_status;
|
||
|
||
/* Get the last target status returned by target_wait(). */
|
||
get_last_target_status (&wait_ptid, &wait_status);
|
||
|
||
/* Make sure we were stopped at a breakpoint. */
|
||
if (wait_status.kind != TARGET_WAITKIND_STOPPED
|
||
|| wait_status.value.sig != TARGET_SIGNAL_TRAP)
|
||
{
|
||
return 0;
|
||
}
|
||
|
||
/* Switched over from WAIT_PID. */
|
||
if (!ptid_equal (wait_ptid, minus_one_ptid)
|
||
&& !ptid_equal (inferior_ptid, wait_ptid))
|
||
{
|
||
struct regcache *regcache = get_thread_regcache (wait_ptid);
|
||
|
||
if (breakpoint_here_p (regcache_read_pc (regcache)))
|
||
{
|
||
/* If stepping, remember current thread to switch back to. */
|
||
if (step)
|
||
deferred_step_ptid = inferior_ptid;
|
||
|
||
/* Switch back to WAIT_PID thread. */
|
||
switch_to_thread (wait_ptid);
|
||
|
||
/* We return 1 to indicate that there is a breakpoint here,
|
||
so we need to step over it before continuing to avoid
|
||
hitting it straight away. */
|
||
return 1;
|
||
}
|
||
}
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* Basic routine for continuing the program in various fashions.
|
||
|
||
ADDR is the address to resume at, or -1 for resume where stopped.
|
||
SIGGNAL is the signal to give it, or 0 for none,
|
||
or -1 for act according to how it stopped.
|
||
STEP is nonzero if should trap after one instruction.
|
||
-1 means return after that and print nothing.
|
||
You should probably set various step_... variables
|
||
before calling here, if you are stepping.
|
||
|
||
You should call clear_proceed_status before calling proceed. */
|
||
|
||
void
|
||
proceed (CORE_ADDR addr, enum target_signal siggnal, int step)
|
||
{
|
||
struct regcache *regcache = get_current_regcache ();
|
||
struct gdbarch *gdbarch = get_regcache_arch (regcache);
|
||
struct thread_info *tp;
|
||
CORE_ADDR pc = regcache_read_pc (regcache);
|
||
int oneproc = 0;
|
||
enum target_signal stop_signal;
|
||
|
||
if (step > 0)
|
||
step_start_function = find_pc_function (pc);
|
||
if (step < 0)
|
||
stop_after_trap = 1;
|
||
|
||
if (addr == (CORE_ADDR) -1)
|
||
{
|
||
if (pc == stop_pc && breakpoint_here_p (pc)
|
||
&& execution_direction != EXEC_REVERSE)
|
||
/* There is a breakpoint at the address we will resume at,
|
||
step one instruction before inserting breakpoints so that
|
||
we do not stop right away (and report a second hit at this
|
||
breakpoint).
|
||
|
||
Note, we don't do this in reverse, because we won't
|
||
actually be executing the breakpoint insn anyway.
|
||
We'll be (un-)executing the previous instruction. */
|
||
|
||
oneproc = 1;
|
||
else if (gdbarch_single_step_through_delay_p (gdbarch)
|
||
&& gdbarch_single_step_through_delay (gdbarch,
|
||
get_current_frame ()))
|
||
/* We stepped onto an instruction that needs to be stepped
|
||
again before re-inserting the breakpoint, do so. */
|
||
oneproc = 1;
|
||
}
|
||
else
|
||
{
|
||
regcache_write_pc (regcache, addr);
|
||
}
|
||
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"infrun: proceed (addr=0x%s, signal=%d, step=%d)\n",
|
||
paddr_nz (addr), siggnal, step);
|
||
|
||
if (non_stop)
|
||
/* In non-stop, each thread is handled individually. The context
|
||
must already be set to the right thread here. */
|
||
;
|
||
else
|
||
{
|
||
/* In a multi-threaded task we may select another thread and
|
||
then continue or step.
|
||
|
||
But if the old thread was stopped at a breakpoint, it will
|
||
immediately cause another breakpoint stop without any
|
||
execution (i.e. it will report a breakpoint hit incorrectly).
|
||
So we must step over it first.
|
||
|
||
prepare_to_proceed checks the current thread against the
|
||
thread that reported the most recent event. If a step-over
|
||
is required it returns TRUE and sets the current thread to
|
||
the old thread. */
|
||
if (prepare_to_proceed (step))
|
||
oneproc = 1;
|
||
}
|
||
|
||
/* prepare_to_proceed may change the current thread. */
|
||
tp = inferior_thread ();
|
||
|
||
if (oneproc)
|
||
{
|
||
tp->trap_expected = 1;
|
||
/* If displaced stepping is enabled, we can step over the
|
||
breakpoint without hitting it, so leave all breakpoints
|
||
inserted. Otherwise we need to disable all breakpoints, step
|
||
one instruction, and then re-add them when that step is
|
||
finished. */
|
||
if (!use_displaced_stepping (gdbarch))
|
||
remove_breakpoints ();
|
||
}
|
||
|
||
/* We can insert breakpoints if we're not trying to step over one,
|
||
or if we are stepping over one but we're using displaced stepping
|
||
to do so. */
|
||
if (! tp->trap_expected || use_displaced_stepping (gdbarch))
|
||
insert_breakpoints ();
|
||
|
||
if (!non_stop)
|
||
{
|
||
/* Pass the last stop signal to the thread we're resuming,
|
||
irrespective of whether the current thread is the thread that
|
||
got the last event or not. This was historically GDB's
|
||
behaviour before keeping a stop_signal per thread. */
|
||
|
||
struct thread_info *last_thread;
|
||
ptid_t last_ptid;
|
||
struct target_waitstatus last_status;
|
||
|
||
get_last_target_status (&last_ptid, &last_status);
|
||
if (!ptid_equal (inferior_ptid, last_ptid)
|
||
&& !ptid_equal (last_ptid, null_ptid)
|
||
&& !ptid_equal (last_ptid, minus_one_ptid))
|
||
{
|
||
last_thread = find_thread_pid (last_ptid);
|
||
if (last_thread)
|
||
{
|
||
tp->stop_signal = last_thread->stop_signal;
|
||
last_thread->stop_signal = TARGET_SIGNAL_0;
|
||
}
|
||
}
|
||
}
|
||
|
||
if (siggnal != TARGET_SIGNAL_DEFAULT)
|
||
tp->stop_signal = siggnal;
|
||
/* If this signal should not be seen by program,
|
||
give it zero. Used for debugging signals. */
|
||
else if (!signal_program[tp->stop_signal])
|
||
tp->stop_signal = TARGET_SIGNAL_0;
|
||
|
||
annotate_starting ();
|
||
|
||
/* Make sure that output from GDB appears before output from the
|
||
inferior. */
|
||
gdb_flush (gdb_stdout);
|
||
|
||
/* Refresh prev_pc value just prior to resuming. This used to be
|
||
done in stop_stepping, however, setting prev_pc there did not handle
|
||
scenarios such as inferior function calls or returning from
|
||
a function via the return command. In those cases, the prev_pc
|
||
value was not set properly for subsequent commands. The prev_pc value
|
||
is used to initialize the starting line number in the ecs. With an
|
||
invalid value, the gdb next command ends up stopping at the position
|
||
represented by the next line table entry past our start position.
|
||
On platforms that generate one line table entry per line, this
|
||
is not a problem. However, on the ia64, the compiler generates
|
||
extraneous line table entries that do not increase the line number.
|
||
When we issue the gdb next command on the ia64 after an inferior call
|
||
or a return command, we often end up a few instructions forward, still
|
||
within the original line we started.
|
||
|
||
An attempt was made to have init_execution_control_state () refresh
|
||
the prev_pc value before calculating the line number. This approach
|
||
did not work because on platforms that use ptrace, the pc register
|
||
cannot be read unless the inferior is stopped. At that point, we
|
||
are not guaranteed the inferior is stopped and so the regcache_read_pc ()
|
||
call can fail. Setting the prev_pc value here ensures the value is
|
||
updated correctly when the inferior is stopped. */
|
||
tp->prev_pc = regcache_read_pc (get_current_regcache ());
|
||
|
||
/* Fill in with reasonable starting values. */
|
||
init_thread_stepping_state (tp);
|
||
|
||
/* Reset to normal state. */
|
||
init_infwait_state ();
|
||
|
||
/* Resume inferior. */
|
||
resume (oneproc || step || bpstat_should_step (), tp->stop_signal);
|
||
|
||
/* Wait for it to stop (if not standalone)
|
||
and in any case decode why it stopped, and act accordingly. */
|
||
/* Do this only if we are not using the event loop, or if the target
|
||
does not support asynchronous execution. */
|
||
if (!target_can_async_p ())
|
||
{
|
||
wait_for_inferior (0);
|
||
normal_stop ();
|
||
}
|
||
}
|
||
|
||
|
||
/* Start remote-debugging of a machine over a serial link. */
|
||
|
||
void
|
||
start_remote (int from_tty)
|
||
{
|
||
struct inferior *inferior;
|
||
init_wait_for_inferior ();
|
||
|
||
inferior = current_inferior ();
|
||
inferior->stop_soon = STOP_QUIETLY_REMOTE;
|
||
|
||
/* Always go on waiting for the target, regardless of the mode. */
|
||
/* FIXME: cagney/1999-09-23: At present it isn't possible to
|
||
indicate to wait_for_inferior that a target should timeout if
|
||
nothing is returned (instead of just blocking). Because of this,
|
||
targets expecting an immediate response need to, internally, set
|
||
things up so that the target_wait() is forced to eventually
|
||
timeout. */
|
||
/* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
|
||
differentiate to its caller what the state of the target is after
|
||
the initial open has been performed. Here we're assuming that
|
||
the target has stopped. It should be possible to eventually have
|
||
target_open() return to the caller an indication that the target
|
||
is currently running and GDB state should be set to the same as
|
||
for an async run. */
|
||
wait_for_inferior (0);
|
||
|
||
/* Now that the inferior has stopped, do any bookkeeping like
|
||
loading shared libraries. We want to do this before normal_stop,
|
||
so that the displayed frame is up to date. */
|
||
post_create_inferior (¤t_target, from_tty);
|
||
|
||
normal_stop ();
|
||
}
|
||
|
||
/* Initialize static vars when a new inferior begins. */
|
||
|
||
void
|
||
init_wait_for_inferior (void)
|
||
{
|
||
/* These are meaningless until the first time through wait_for_inferior. */
|
||
|
||
breakpoint_init_inferior (inf_starting);
|
||
|
||
/* The first resume is not following a fork/vfork/exec. */
|
||
pending_follow.kind = TARGET_WAITKIND_SPURIOUS; /* I.e., none. */
|
||
|
||
clear_proceed_status ();
|
||
|
||
stepping_past_singlestep_breakpoint = 0;
|
||
deferred_step_ptid = null_ptid;
|
||
|
||
target_last_wait_ptid = minus_one_ptid;
|
||
|
||
previous_inferior_ptid = null_ptid;
|
||
init_infwait_state ();
|
||
|
||
displaced_step_clear ();
|
||
}
|
||
|
||
|
||
/* This enum encodes possible reasons for doing a target_wait, so that
|
||
wfi can call target_wait in one place. (Ultimately the call will be
|
||
moved out of the infinite loop entirely.) */
|
||
|
||
enum infwait_states
|
||
{
|
||
infwait_normal_state,
|
||
infwait_thread_hop_state,
|
||
infwait_step_watch_state,
|
||
infwait_nonstep_watch_state
|
||
};
|
||
|
||
/* Why did the inferior stop? Used to print the appropriate messages
|
||
to the interface from within handle_inferior_event(). */
|
||
enum inferior_stop_reason
|
||
{
|
||
/* Step, next, nexti, stepi finished. */
|
||
END_STEPPING_RANGE,
|
||
/* Inferior terminated by signal. */
|
||
SIGNAL_EXITED,
|
||
/* Inferior exited. */
|
||
EXITED,
|
||
/* Inferior received signal, and user asked to be notified. */
|
||
SIGNAL_RECEIVED,
|
||
/* Reverse execution -- target ran out of history info. */
|
||
NO_HISTORY
|
||
};
|
||
|
||
/* The PTID we'll do a target_wait on.*/
|
||
ptid_t waiton_ptid;
|
||
|
||
/* Current inferior wait state. */
|
||
enum infwait_states infwait_state;
|
||
|
||
/* Data to be passed around while handling an event. This data is
|
||
discarded between events. */
|
||
struct execution_control_state
|
||
{
|
||
ptid_t ptid;
|
||
/* The thread that got the event, if this was a thread event; NULL
|
||
otherwise. */
|
||
struct thread_info *event_thread;
|
||
|
||
struct target_waitstatus ws;
|
||
int random_signal;
|
||
CORE_ADDR stop_func_start;
|
||
CORE_ADDR stop_func_end;
|
||
char *stop_func_name;
|
||
int new_thread_event;
|
||
int wait_some_more;
|
||
};
|
||
|
||
void init_execution_control_state (struct execution_control_state *ecs);
|
||
|
||
void handle_inferior_event (struct execution_control_state *ecs);
|
||
|
||
static void handle_step_into_function (struct execution_control_state *ecs);
|
||
static void handle_step_into_function_backward (struct execution_control_state *ecs);
|
||
static void insert_step_resume_breakpoint_at_frame (struct frame_info *step_frame);
|
||
static void insert_step_resume_breakpoint_at_caller (struct frame_info *);
|
||
static void insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal,
|
||
struct frame_id sr_id);
|
||
static void insert_longjmp_resume_breakpoint (CORE_ADDR);
|
||
|
||
static void stop_stepping (struct execution_control_state *ecs);
|
||
static void prepare_to_wait (struct execution_control_state *ecs);
|
||
static void keep_going (struct execution_control_state *ecs);
|
||
static void print_stop_reason (enum inferior_stop_reason stop_reason,
|
||
int stop_info);
|
||
|
||
/* Callback for iterate over threads. If the thread is stopped, but
|
||
the user/frontend doesn't know about that yet, go through
|
||
normal_stop, as if the thread had just stopped now. ARG points at
|
||
a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
|
||
ptid_is_pid(PTID) is true, applies to all threads of the process
|
||
pointed at by PTID. Otherwise, apply only to the thread pointed by
|
||
PTID. */
|
||
|
||
static int
|
||
infrun_thread_stop_requested_callback (struct thread_info *info, void *arg)
|
||
{
|
||
ptid_t ptid = * (ptid_t *) arg;
|
||
|
||
if ((ptid_equal (info->ptid, ptid)
|
||
|| ptid_equal (minus_one_ptid, ptid)
|
||
|| (ptid_is_pid (ptid)
|
||
&& ptid_get_pid (ptid) == ptid_get_pid (info->ptid)))
|
||
&& is_running (info->ptid)
|
||
&& !is_executing (info->ptid))
|
||
{
|
||
struct cleanup *old_chain;
|
||
struct execution_control_state ecss;
|
||
struct execution_control_state *ecs = &ecss;
|
||
|
||
memset (ecs, 0, sizeof (*ecs));
|
||
|
||
old_chain = make_cleanup_restore_current_thread ();
|
||
|
||
switch_to_thread (info->ptid);
|
||
|
||
/* Go through handle_inferior_event/normal_stop, so we always
|
||
have consistent output as if the stop event had been
|
||
reported. */
|
||
ecs->ptid = info->ptid;
|
||
ecs->event_thread = find_thread_pid (info->ptid);
|
||
ecs->ws.kind = TARGET_WAITKIND_STOPPED;
|
||
ecs->ws.value.sig = TARGET_SIGNAL_0;
|
||
|
||
handle_inferior_event (ecs);
|
||
|
||
if (!ecs->wait_some_more)
|
||
{
|
||
struct thread_info *tp;
|
||
|
||
normal_stop ();
|
||
|
||
/* Finish off the continuations. The continations
|
||
themselves are responsible for realising the thread
|
||
didn't finish what it was supposed to do. */
|
||
tp = inferior_thread ();
|
||
do_all_intermediate_continuations_thread (tp);
|
||
do_all_continuations_thread (tp);
|
||
}
|
||
|
||
do_cleanups (old_chain);
|
||
}
|
||
|
||
return 0;
|
||
}
|
||
|
||
/* This function is attached as a "thread_stop_requested" observer.
|
||
Cleanup local state that assumed the PTID was to be resumed, and
|
||
report the stop to the frontend. */
|
||
|
||
void
|
||
infrun_thread_stop_requested (ptid_t ptid)
|
||
{
|
||
struct displaced_step_request *it, *next, *prev = NULL;
|
||
|
||
/* PTID was requested to stop. Remove it from the displaced
|
||
stepping queue, so we don't try to resume it automatically. */
|
||
for (it = displaced_step_request_queue; it; it = next)
|
||
{
|
||
next = it->next;
|
||
|
||
if (ptid_equal (it->ptid, ptid)
|
||
|| ptid_equal (minus_one_ptid, ptid)
|
||
|| (ptid_is_pid (ptid)
|
||
&& ptid_get_pid (ptid) == ptid_get_pid (it->ptid)))
|
||
{
|
||
if (displaced_step_request_queue == it)
|
||
displaced_step_request_queue = it->next;
|
||
else
|
||
prev->next = it->next;
|
||
|
||
xfree (it);
|
||
}
|
||
else
|
||
prev = it;
|
||
}
|
||
|
||
iterate_over_threads (infrun_thread_stop_requested_callback, &ptid);
|
||
}
|
||
|
||
/* Callback for iterate_over_threads. */
|
||
|
||
static int
|
||
delete_step_resume_breakpoint_callback (struct thread_info *info, void *data)
|
||
{
|
||
if (is_exited (info->ptid))
|
||
return 0;
|
||
|
||
delete_step_resume_breakpoint (info);
|
||
return 0;
|
||
}
|
||
|
||
/* In all-stop, delete the step resume breakpoint of any thread that
|
||
had one. In non-stop, delete the step resume breakpoint of the
|
||
thread that just stopped. */
|
||
|
||
static void
|
||
delete_step_thread_step_resume_breakpoint (void)
|
||
{
|
||
if (!target_has_execution
|
||
|| ptid_equal (inferior_ptid, null_ptid))
|
||
/* If the inferior has exited, we have already deleted the step
|
||
resume breakpoints out of GDB's lists. */
|
||
return;
|
||
|
||
if (non_stop)
|
||
{
|
||
/* If in non-stop mode, only delete the step-resume or
|
||
longjmp-resume breakpoint of the thread that just stopped
|
||
stepping. */
|
||
struct thread_info *tp = inferior_thread ();
|
||
delete_step_resume_breakpoint (tp);
|
||
}
|
||
else
|
||
/* In all-stop mode, delete all step-resume and longjmp-resume
|
||
breakpoints of any thread that had them. */
|
||
iterate_over_threads (delete_step_resume_breakpoint_callback, NULL);
|
||
}
|
||
|
||
/* A cleanup wrapper. */
|
||
|
||
static void
|
||
delete_step_thread_step_resume_breakpoint_cleanup (void *arg)
|
||
{
|
||
delete_step_thread_step_resume_breakpoint ();
|
||
}
|
||
|
||
/* Wait for control to return from inferior to debugger.
|
||
|
||
If TREAT_EXEC_AS_SIGTRAP is non-zero, then handle EXEC signals
|
||
as if they were SIGTRAP signals. This can be useful during
|
||
the startup sequence on some targets such as HP/UX, where
|
||
we receive an EXEC event instead of the expected SIGTRAP.
|
||
|
||
If inferior gets a signal, we may decide to start it up again
|
||
instead of returning. That is why there is a loop in this function.
|
||
When this function actually returns it means the inferior
|
||
should be left stopped and GDB should read more commands. */
|
||
|
||
void
|
||
wait_for_inferior (int treat_exec_as_sigtrap)
|
||
{
|
||
struct cleanup *old_cleanups;
|
||
struct execution_control_state ecss;
|
||
struct execution_control_state *ecs;
|
||
|
||
if (debug_infrun)
|
||
fprintf_unfiltered
|
||
(gdb_stdlog, "infrun: wait_for_inferior (treat_exec_as_sigtrap=%d)\n",
|
||
treat_exec_as_sigtrap);
|
||
|
||
old_cleanups =
|
||
make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup, NULL);
|
||
|
||
ecs = &ecss;
|
||
memset (ecs, 0, sizeof (*ecs));
|
||
|
||
overlay_cache_invalid = 1;
|
||
|
||
/* We'll update this if & when we switch to a new thread. */
|
||
previous_inferior_ptid = inferior_ptid;
|
||
|
||
/* We have to invalidate the registers BEFORE calling target_wait
|
||
because they can be loaded from the target while in target_wait.
|
||
This makes remote debugging a bit more efficient for those
|
||
targets that provide critical registers as part of their normal
|
||
status mechanism. */
|
||
|
||
registers_changed ();
|
||
|
||
while (1)
|
||
{
|
||
if (deprecated_target_wait_hook)
|
||
ecs->ptid = deprecated_target_wait_hook (waiton_ptid, &ecs->ws);
|
||
else
|
||
ecs->ptid = target_wait (waiton_ptid, &ecs->ws);
|
||
|
||
if (treat_exec_as_sigtrap && ecs->ws.kind == TARGET_WAITKIND_EXECD)
|
||
{
|
||
xfree (ecs->ws.value.execd_pathname);
|
||
ecs->ws.kind = TARGET_WAITKIND_STOPPED;
|
||
ecs->ws.value.sig = TARGET_SIGNAL_TRAP;
|
||
}
|
||
|
||
/* Now figure out what to do with the result of the result. */
|
||
handle_inferior_event (ecs);
|
||
|
||
if (!ecs->wait_some_more)
|
||
break;
|
||
}
|
||
|
||
do_cleanups (old_cleanups);
|
||
}
|
||
|
||
/* Asynchronous version of wait_for_inferior. It is called by the
|
||
event loop whenever a change of state is detected on the file
|
||
descriptor corresponding to the target. It can be called more than
|
||
once to complete a single execution command. In such cases we need
|
||
to keep the state in a global variable ECSS. If it is the last time
|
||
that this function is called for a single execution command, then
|
||
report to the user that the inferior has stopped, and do the
|
||
necessary cleanups. */
|
||
|
||
void
|
||
fetch_inferior_event (void *client_data)
|
||
{
|
||
struct execution_control_state ecss;
|
||
struct execution_control_state *ecs = &ecss;
|
||
struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
|
||
int was_sync = sync_execution;
|
||
|
||
memset (ecs, 0, sizeof (*ecs));
|
||
|
||
overlay_cache_invalid = 1;
|
||
|
||
/* We can only rely on wait_for_more being correct before handling
|
||
the event in all-stop, but previous_inferior_ptid isn't used in
|
||
non-stop. */
|
||
if (!ecs->wait_some_more)
|
||
/* We'll update this if & when we switch to a new thread. */
|
||
previous_inferior_ptid = inferior_ptid;
|
||
|
||
if (non_stop)
|
||
/* In non-stop mode, the user/frontend should not notice a thread
|
||
switch due to internal events. Make sure we reverse to the
|
||
user selected thread and frame after handling the event and
|
||
running any breakpoint commands. */
|
||
make_cleanup_restore_current_thread ();
|
||
|
||
/* We have to invalidate the registers BEFORE calling target_wait
|
||
because they can be loaded from the target while in target_wait.
|
||
This makes remote debugging a bit more efficient for those
|
||
targets that provide critical registers as part of their normal
|
||
status mechanism. */
|
||
|
||
registers_changed ();
|
||
|
||
if (deprecated_target_wait_hook)
|
||
ecs->ptid =
|
||
deprecated_target_wait_hook (waiton_ptid, &ecs->ws);
|
||
else
|
||
ecs->ptid = target_wait (waiton_ptid, &ecs->ws);
|
||
|
||
if (non_stop
|
||
&& ecs->ws.kind != TARGET_WAITKIND_IGNORE
|
||
&& ecs->ws.kind != TARGET_WAITKIND_EXITED
|
||
&& ecs->ws.kind != TARGET_WAITKIND_SIGNALLED)
|
||
/* In non-stop mode, each thread is handled individually. Switch
|
||
early, so the global state is set correctly for this
|
||
thread. */
|
||
context_switch (ecs->ptid);
|
||
|
||
/* Now figure out what to do with the result of the result. */
|
||
handle_inferior_event (ecs);
|
||
|
||
if (!ecs->wait_some_more)
|
||
{
|
||
struct inferior *inf = find_inferior_pid (ptid_get_pid (ecs->ptid));
|
||
|
||
delete_step_thread_step_resume_breakpoint ();
|
||
|
||
/* We may not find an inferior if this was a process exit. */
|
||
if (inf == NULL || inf->stop_soon == NO_STOP_QUIETLY)
|
||
normal_stop ();
|
||
|
||
if (target_has_execution
|
||
&& ecs->ws.kind != TARGET_WAITKIND_EXITED
|
||
&& ecs->ws.kind != TARGET_WAITKIND_SIGNALLED
|
||
&& ecs->event_thread->step_multi
|
||
&& ecs->event_thread->stop_step)
|
||
inferior_event_handler (INF_EXEC_CONTINUE, NULL);
|
||
else
|
||
inferior_event_handler (INF_EXEC_COMPLETE, NULL);
|
||
}
|
||
|
||
/* Revert thread and frame. */
|
||
do_cleanups (old_chain);
|
||
|
||
/* If the inferior was in sync execution mode, and now isn't,
|
||
restore the prompt. */
|
||
if (was_sync && !sync_execution)
|
||
display_gdb_prompt (0);
|
||
}
|
||
|
||
/* Prepare an execution control state for looping through a
|
||
wait_for_inferior-type loop. */
|
||
|
||
void
|
||
init_execution_control_state (struct execution_control_state *ecs)
|
||
{
|
||
ecs->random_signal = 0;
|
||
}
|
||
|
||
/* Clear context switchable stepping state. */
|
||
|
||
void
|
||
init_thread_stepping_state (struct thread_info *tss)
|
||
{
|
||
struct symtab_and_line sal;
|
||
|
||
tss->stepping_over_breakpoint = 0;
|
||
tss->step_after_step_resume_breakpoint = 0;
|
||
tss->stepping_through_solib_after_catch = 0;
|
||
tss->stepping_through_solib_catchpoints = NULL;
|
||
|
||
sal = find_pc_line (tss->prev_pc, 0);
|
||
tss->current_line = sal.line;
|
||
tss->current_symtab = sal.symtab;
|
||
}
|
||
|
||
/* Return the cached copy of the last pid/waitstatus returned by
|
||
target_wait()/deprecated_target_wait_hook(). The data is actually
|
||
cached by handle_inferior_event(), which gets called immediately
|
||
after target_wait()/deprecated_target_wait_hook(). */
|
||
|
||
void
|
||
get_last_target_status (ptid_t *ptidp, struct target_waitstatus *status)
|
||
{
|
||
*ptidp = target_last_wait_ptid;
|
||
*status = target_last_waitstatus;
|
||
}
|
||
|
||
void
|
||
nullify_last_target_wait_ptid (void)
|
||
{
|
||
target_last_wait_ptid = minus_one_ptid;
|
||
}
|
||
|
||
/* Switch thread contexts. */
|
||
|
||
static void
|
||
context_switch (ptid_t ptid)
|
||
{
|
||
if (debug_infrun)
|
||
{
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: Switching context from %s ",
|
||
target_pid_to_str (inferior_ptid));
|
||
fprintf_unfiltered (gdb_stdlog, "to %s\n",
|
||
target_pid_to_str (ptid));
|
||
}
|
||
|
||
switch_to_thread (ptid);
|
||
}
|
||
|
||
static void
|
||
adjust_pc_after_break (struct execution_control_state *ecs)
|
||
{
|
||
struct regcache *regcache;
|
||
struct gdbarch *gdbarch;
|
||
CORE_ADDR breakpoint_pc;
|
||
|
||
/* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
|
||
we aren't, just return.
|
||
|
||
We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
|
||
affected by gdbarch_decr_pc_after_break. Other waitkinds which are
|
||
implemented by software breakpoints should be handled through the normal
|
||
breakpoint layer.
|
||
|
||
NOTE drow/2004-01-31: On some targets, breakpoints may generate
|
||
different signals (SIGILL or SIGEMT for instance), but it is less
|
||
clear where the PC is pointing afterwards. It may not match
|
||
gdbarch_decr_pc_after_break. I don't know any specific target that
|
||
generates these signals at breakpoints (the code has been in GDB since at
|
||
least 1992) so I can not guess how to handle them here.
|
||
|
||
In earlier versions of GDB, a target with
|
||
gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
|
||
watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
|
||
target with both of these set in GDB history, and it seems unlikely to be
|
||
correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
|
||
|
||
if (ecs->ws.kind != TARGET_WAITKIND_STOPPED)
|
||
return;
|
||
|
||
if (ecs->ws.value.sig != TARGET_SIGNAL_TRAP)
|
||
return;
|
||
|
||
/* In reverse execution, when a breakpoint is hit, the instruction
|
||
under it has already been de-executed. The reported PC always
|
||
points at the breakpoint address, so adjusting it further would
|
||
be wrong. E.g., consider this case on a decr_pc_after_break == 1
|
||
architecture:
|
||
|
||
B1 0x08000000 : INSN1
|
||
B2 0x08000001 : INSN2
|
||
0x08000002 : INSN3
|
||
PC -> 0x08000003 : INSN4
|
||
|
||
Say you're stopped at 0x08000003 as above. Reverse continuing
|
||
from that point should hit B2 as below. Reading the PC when the
|
||
SIGTRAP is reported should read 0x08000001 and INSN2 should have
|
||
been de-executed already.
|
||
|
||
B1 0x08000000 : INSN1
|
||
B2 PC -> 0x08000001 : INSN2
|
||
0x08000002 : INSN3
|
||
0x08000003 : INSN4
|
||
|
||
We can't apply the same logic as for forward execution, because
|
||
we would wrongly adjust the PC to 0x08000000, since there's a
|
||
breakpoint at PC - 1. We'd then report a hit on B1, although
|
||
INSN1 hadn't been de-executed yet. Doing nothing is the correct
|
||
behaviour. */
|
||
if (execution_direction == EXEC_REVERSE)
|
||
return;
|
||
|
||
/* If this target does not decrement the PC after breakpoints, then
|
||
we have nothing to do. */
|
||
regcache = get_thread_regcache (ecs->ptid);
|
||
gdbarch = get_regcache_arch (regcache);
|
||
if (gdbarch_decr_pc_after_break (gdbarch) == 0)
|
||
return;
|
||
|
||
/* Find the location where (if we've hit a breakpoint) the
|
||
breakpoint would be. */
|
||
breakpoint_pc = regcache_read_pc (regcache)
|
||
- gdbarch_decr_pc_after_break (gdbarch);
|
||
|
||
/* Check whether there actually is a software breakpoint inserted at
|
||
that location.
|
||
|
||
If in non-stop mode, a race condition is possible where we've
|
||
removed a breakpoint, but stop events for that breakpoint were
|
||
already queued and arrive later. To suppress those spurious
|
||
SIGTRAPs, we keep a list of such breakpoint locations for a bit,
|
||
and retire them after a number of stop events are reported. */
|
||
if (software_breakpoint_inserted_here_p (breakpoint_pc)
|
||
|| (non_stop && moribund_breakpoint_here_p (breakpoint_pc)))
|
||
{
|
||
/* When using hardware single-step, a SIGTRAP is reported for both
|
||
a completed single-step and a software breakpoint. Need to
|
||
differentiate between the two, as the latter needs adjusting
|
||
but the former does not.
|
||
|
||
The SIGTRAP can be due to a completed hardware single-step only if
|
||
- we didn't insert software single-step breakpoints
|
||
- the thread to be examined is still the current thread
|
||
- this thread is currently being stepped
|
||
|
||
If any of these events did not occur, we must have stopped due
|
||
to hitting a software breakpoint, and have to back up to the
|
||
breakpoint address.
|
||
|
||
As a special case, we could have hardware single-stepped a
|
||
software breakpoint. In this case (prev_pc == breakpoint_pc),
|
||
we also need to back up to the breakpoint address. */
|
||
|
||
if (singlestep_breakpoints_inserted_p
|
||
|| !ptid_equal (ecs->ptid, inferior_ptid)
|
||
|| !currently_stepping (ecs->event_thread)
|
||
|| ecs->event_thread->prev_pc == breakpoint_pc)
|
||
regcache_write_pc (regcache, breakpoint_pc);
|
||
}
|
||
}
|
||
|
||
void
|
||
init_infwait_state (void)
|
||
{
|
||
waiton_ptid = pid_to_ptid (-1);
|
||
infwait_state = infwait_normal_state;
|
||
}
|
||
|
||
void
|
||
error_is_running (void)
|
||
{
|
||
error (_("\
|
||
Cannot execute this command while the selected thread is running."));
|
||
}
|
||
|
||
void
|
||
ensure_not_running (void)
|
||
{
|
||
if (is_running (inferior_ptid))
|
||
error_is_running ();
|
||
}
|
||
|
||
/* Given an execution control state that has been freshly filled in
|
||
by an event from the inferior, figure out what it means and take
|
||
appropriate action. */
|
||
|
||
void
|
||
handle_inferior_event (struct execution_control_state *ecs)
|
||
{
|
||
int sw_single_step_trap_p = 0;
|
||
int stopped_by_watchpoint;
|
||
int stepped_after_stopped_by_watchpoint = 0;
|
||
struct symtab_and_line stop_pc_sal;
|
||
enum stop_kind stop_soon;
|
||
|
||
if (ecs->ws.kind != TARGET_WAITKIND_EXITED
|
||
&& ecs->ws.kind != TARGET_WAITKIND_SIGNALLED
|
||
&& ecs->ws.kind != TARGET_WAITKIND_IGNORE)
|
||
{
|
||
struct inferior *inf = find_inferior_pid (ptid_get_pid (ecs->ptid));
|
||
gdb_assert (inf);
|
||
stop_soon = inf->stop_soon;
|
||
}
|
||
else
|
||
stop_soon = NO_STOP_QUIETLY;
|
||
|
||
/* Cache the last pid/waitstatus. */
|
||
target_last_wait_ptid = ecs->ptid;
|
||
target_last_waitstatus = ecs->ws;
|
||
|
||
/* Always clear state belonging to the previous time we stopped. */
|
||
stop_stack_dummy = 0;
|
||
|
||
/* If it's a new process, add it to the thread database */
|
||
|
||
ecs->new_thread_event = (!ptid_equal (ecs->ptid, inferior_ptid)
|
||
&& !ptid_equal (ecs->ptid, minus_one_ptid)
|
||
&& !in_thread_list (ecs->ptid));
|
||
|
||
if (ecs->ws.kind != TARGET_WAITKIND_EXITED
|
||
&& ecs->ws.kind != TARGET_WAITKIND_SIGNALLED && ecs->new_thread_event)
|
||
add_thread (ecs->ptid);
|
||
|
||
ecs->event_thread = find_thread_pid (ecs->ptid);
|
||
|
||
/* Dependent on valid ECS->EVENT_THREAD. */
|
||
adjust_pc_after_break (ecs);
|
||
|
||
/* Dependent on the current PC value modified by adjust_pc_after_break. */
|
||
reinit_frame_cache ();
|
||
|
||
if (ecs->ws.kind != TARGET_WAITKIND_IGNORE)
|
||
{
|
||
breakpoint_retire_moribund ();
|
||
|
||
/* Mark the non-executing threads accordingly. */
|
||
if (!non_stop
|
||
|| ecs->ws.kind == TARGET_WAITKIND_EXITED
|
||
|| ecs->ws.kind == TARGET_WAITKIND_SIGNALLED)
|
||
set_executing (pid_to_ptid (-1), 0);
|
||
else
|
||
set_executing (ecs->ptid, 0);
|
||
}
|
||
|
||
switch (infwait_state)
|
||
{
|
||
case infwait_thread_hop_state:
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: infwait_thread_hop_state\n");
|
||
/* Cancel the waiton_ptid. */
|
||
waiton_ptid = pid_to_ptid (-1);
|
||
break;
|
||
|
||
case infwait_normal_state:
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: infwait_normal_state\n");
|
||
break;
|
||
|
||
case infwait_step_watch_state:
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"infrun: infwait_step_watch_state\n");
|
||
|
||
stepped_after_stopped_by_watchpoint = 1;
|
||
break;
|
||
|
||
case infwait_nonstep_watch_state:
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"infrun: infwait_nonstep_watch_state\n");
|
||
insert_breakpoints ();
|
||
|
||
/* FIXME-maybe: is this cleaner than setting a flag? Does it
|
||
handle things like signals arriving and other things happening
|
||
in combination correctly? */
|
||
stepped_after_stopped_by_watchpoint = 1;
|
||
break;
|
||
|
||
default:
|
||
internal_error (__FILE__, __LINE__, _("bad switch"));
|
||
}
|
||
infwait_state = infwait_normal_state;
|
||
|
||
switch (ecs->ws.kind)
|
||
{
|
||
case TARGET_WAITKIND_LOADED:
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_LOADED\n");
|
||
/* Ignore gracefully during startup of the inferior, as it might
|
||
be the shell which has just loaded some objects, otherwise
|
||
add the symbols for the newly loaded objects. Also ignore at
|
||
the beginning of an attach or remote session; we will query
|
||
the full list of libraries once the connection is
|
||
established. */
|
||
if (stop_soon == NO_STOP_QUIETLY)
|
||
{
|
||
/* Check for any newly added shared libraries if we're
|
||
supposed to be adding them automatically. Switch
|
||
terminal for any messages produced by
|
||
breakpoint_re_set. */
|
||
target_terminal_ours_for_output ();
|
||
/* NOTE: cagney/2003-11-25: Make certain that the target
|
||
stack's section table is kept up-to-date. Architectures,
|
||
(e.g., PPC64), use the section table to perform
|
||
operations such as address => section name and hence
|
||
require the table to contain all sections (including
|
||
those found in shared libraries). */
|
||
/* NOTE: cagney/2003-11-25: Pass current_target and not
|
||
exec_ops to SOLIB_ADD. This is because current GDB is
|
||
only tooled to propagate section_table changes out from
|
||
the "current_target" (see target_resize_to_sections), and
|
||
not up from the exec stratum. This, of course, isn't
|
||
right. "infrun.c" should only interact with the
|
||
exec/process stratum, instead relying on the target stack
|
||
to propagate relevant changes (stop, section table
|
||
changed, ...) up to other layers. */
|
||
#ifdef SOLIB_ADD
|
||
SOLIB_ADD (NULL, 0, ¤t_target, auto_solib_add);
|
||
#else
|
||
solib_add (NULL, 0, ¤t_target, auto_solib_add);
|
||
#endif
|
||
target_terminal_inferior ();
|
||
|
||
/* If requested, stop when the dynamic linker notifies
|
||
gdb of events. This allows the user to get control
|
||
and place breakpoints in initializer routines for
|
||
dynamically loaded objects (among other things). */
|
||
if (stop_on_solib_events)
|
||
{
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
|
||
/* NOTE drow/2007-05-11: This might be a good place to check
|
||
for "catch load". */
|
||
}
|
||
|
||
/* If we are skipping through a shell, or through shared library
|
||
loading that we aren't interested in, resume the program. If
|
||
we're running the program normally, also resume. But stop if
|
||
we're attaching or setting up a remote connection. */
|
||
if (stop_soon == STOP_QUIETLY || stop_soon == NO_STOP_QUIETLY)
|
||
{
|
||
/* Loading of shared libraries might have changed breakpoint
|
||
addresses. Make sure new breakpoints are inserted. */
|
||
if (stop_soon == NO_STOP_QUIETLY
|
||
&& !breakpoints_always_inserted_mode ())
|
||
insert_breakpoints ();
|
||
resume (0, TARGET_SIGNAL_0);
|
||
prepare_to_wait (ecs);
|
||
return;
|
||
}
|
||
|
||
break;
|
||
|
||
case TARGET_WAITKIND_SPURIOUS:
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SPURIOUS\n");
|
||
resume (0, TARGET_SIGNAL_0);
|
||
prepare_to_wait (ecs);
|
||
return;
|
||
|
||
case TARGET_WAITKIND_EXITED:
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXITED\n");
|
||
target_terminal_ours (); /* Must do this before mourn anyway */
|
||
print_stop_reason (EXITED, ecs->ws.value.integer);
|
||
|
||
/* Record the exit code in the convenience variable $_exitcode, so
|
||
that the user can inspect this again later. */
|
||
set_internalvar (lookup_internalvar ("_exitcode"),
|
||
value_from_longest (builtin_type_int32,
|
||
(LONGEST) ecs->ws.value.integer));
|
||
gdb_flush (gdb_stdout);
|
||
target_mourn_inferior ();
|
||
singlestep_breakpoints_inserted_p = 0;
|
||
stop_print_frame = 0;
|
||
stop_stepping (ecs);
|
||
return;
|
||
|
||
case TARGET_WAITKIND_SIGNALLED:
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SIGNALLED\n");
|
||
stop_print_frame = 0;
|
||
target_terminal_ours (); /* Must do this before mourn anyway */
|
||
|
||
/* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
|
||
reach here unless the inferior is dead. However, for years
|
||
target_kill() was called here, which hints that fatal signals aren't
|
||
really fatal on some systems. If that's true, then some changes
|
||
may be needed. */
|
||
target_mourn_inferior ();
|
||
|
||
print_stop_reason (SIGNAL_EXITED, ecs->ws.value.sig);
|
||
singlestep_breakpoints_inserted_p = 0;
|
||
stop_stepping (ecs);
|
||
return;
|
||
|
||
/* The following are the only cases in which we keep going;
|
||
the above cases end in a continue or goto. */
|
||
case TARGET_WAITKIND_FORKED:
|
||
case TARGET_WAITKIND_VFORKED:
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_FORKED\n");
|
||
pending_follow.kind = ecs->ws.kind;
|
||
|
||
pending_follow.fork_event.parent_pid = ecs->ptid;
|
||
pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
|
||
|
||
if (!ptid_equal (ecs->ptid, inferior_ptid))
|
||
{
|
||
context_switch (ecs->ptid);
|
||
reinit_frame_cache ();
|
||
}
|
||
|
||
stop_pc = read_pc ();
|
||
|
||
ecs->event_thread->stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid);
|
||
|
||
ecs->random_signal = !bpstat_explains_signal (ecs->event_thread->stop_bpstat);
|
||
|
||
/* If no catchpoint triggered for this, then keep going. */
|
||
if (ecs->random_signal)
|
||
{
|
||
ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
ecs->event_thread->stop_signal = TARGET_SIGNAL_TRAP;
|
||
goto process_event_stop_test;
|
||
|
||
case TARGET_WAITKIND_EXECD:
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXECD\n");
|
||
pending_follow.execd_pathname =
|
||
savestring (ecs->ws.value.execd_pathname,
|
||
strlen (ecs->ws.value.execd_pathname));
|
||
|
||
if (!ptid_equal (ecs->ptid, inferior_ptid))
|
||
{
|
||
context_switch (ecs->ptid);
|
||
reinit_frame_cache ();
|
||
}
|
||
|
||
stop_pc = read_pc ();
|
||
|
||
/* This causes the eventpoints and symbol table to be reset.
|
||
Must do this now, before trying to determine whether to
|
||
stop. */
|
||
follow_exec (inferior_ptid, pending_follow.execd_pathname);
|
||
xfree (pending_follow.execd_pathname);
|
||
|
||
ecs->event_thread->stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid);
|
||
ecs->random_signal = !bpstat_explains_signal (ecs->event_thread->stop_bpstat);
|
||
|
||
/* If no catchpoint triggered for this, then keep going. */
|
||
if (ecs->random_signal)
|
||
{
|
||
ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
ecs->event_thread->stop_signal = TARGET_SIGNAL_TRAP;
|
||
goto process_event_stop_test;
|
||
|
||
/* Be careful not to try to gather much state about a thread
|
||
that's in a syscall. It's frequently a losing proposition. */
|
||
case TARGET_WAITKIND_SYSCALL_ENTRY:
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
|
||
resume (0, TARGET_SIGNAL_0);
|
||
prepare_to_wait (ecs);
|
||
return;
|
||
|
||
/* Before examining the threads further, step this thread to
|
||
get it entirely out of the syscall. (We get notice of the
|
||
event when the thread is just on the verge of exiting a
|
||
syscall. Stepping one instruction seems to get it back
|
||
into user code.) */
|
||
case TARGET_WAITKIND_SYSCALL_RETURN:
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
|
||
target_resume (ecs->ptid, 1, TARGET_SIGNAL_0);
|
||
prepare_to_wait (ecs);
|
||
return;
|
||
|
||
case TARGET_WAITKIND_STOPPED:
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_STOPPED\n");
|
||
ecs->event_thread->stop_signal = ecs->ws.value.sig;
|
||
break;
|
||
|
||
case TARGET_WAITKIND_NO_HISTORY:
|
||
/* Reverse execution: target ran out of history info. */
|
||
stop_pc = read_pc ();
|
||
print_stop_reason (NO_HISTORY, 0);
|
||
stop_stepping (ecs);
|
||
return;
|
||
|
||
/* We had an event in the inferior, but we are not interested
|
||
in handling it at this level. The lower layers have already
|
||
done what needs to be done, if anything.
|
||
|
||
One of the possible circumstances for this is when the
|
||
inferior produces output for the console. The inferior has
|
||
not stopped, and we are ignoring the event. Another possible
|
||
circumstance is any event which the lower level knows will be
|
||
reported multiple times without an intervening resume. */
|
||
case TARGET_WAITKIND_IGNORE:
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_IGNORE\n");
|
||
prepare_to_wait (ecs);
|
||
return;
|
||
}
|
||
|
||
if (ecs->new_thread_event)
|
||
{
|
||
if (non_stop)
|
||
/* Non-stop assumes that the target handles adding new threads
|
||
to the thread list. */
|
||
internal_error (__FILE__, __LINE__, "\
|
||
targets should add new threads to the thread list themselves in non-stop mode.");
|
||
|
||
/* We may want to consider not doing a resume here in order to
|
||
give the user a chance to play with the new thread. It might
|
||
be good to make that a user-settable option. */
|
||
|
||
/* At this point, all threads are stopped (happens automatically
|
||
in either the OS or the native code). Therefore we need to
|
||
continue all threads in order to make progress. */
|
||
|
||
target_resume (RESUME_ALL, 0, TARGET_SIGNAL_0);
|
||
prepare_to_wait (ecs);
|
||
return;
|
||
}
|
||
|
||
if (ecs->ws.kind == TARGET_WAITKIND_STOPPED)
|
||
{
|
||
/* Do we need to clean up the state of a thread that has
|
||
completed a displaced single-step? (Doing so usually affects
|
||
the PC, so do it here, before we set stop_pc.) */
|
||
displaced_step_fixup (ecs->ptid, ecs->event_thread->stop_signal);
|
||
|
||
/* If we either finished a single-step or hit a breakpoint, but
|
||
the user wanted this thread to be stopped, pretend we got a
|
||
SIG0 (generic unsignaled stop). */
|
||
|
||
if (ecs->event_thread->stop_requested
|
||
&& ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP)
|
||
ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
|
||
}
|
||
|
||
stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
|
||
|
||
if (debug_infrun)
|
||
{
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: stop_pc = 0x%s\n",
|
||
paddr_nz (stop_pc));
|
||
if (STOPPED_BY_WATCHPOINT (&ecs->ws))
|
||
{
|
||
CORE_ADDR addr;
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: stopped by watchpoint\n");
|
||
|
||
if (target_stopped_data_address (¤t_target, &addr))
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"infrun: stopped data address = 0x%s\n",
|
||
paddr_nz (addr));
|
||
else
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"infrun: (no data address available)\n");
|
||
}
|
||
}
|
||
|
||
if (stepping_past_singlestep_breakpoint)
|
||
{
|
||
gdb_assert (singlestep_breakpoints_inserted_p);
|
||
gdb_assert (ptid_equal (singlestep_ptid, ecs->ptid));
|
||
gdb_assert (!ptid_equal (singlestep_ptid, saved_singlestep_ptid));
|
||
|
||
stepping_past_singlestep_breakpoint = 0;
|
||
|
||
/* We've either finished single-stepping past the single-step
|
||
breakpoint, or stopped for some other reason. It would be nice if
|
||
we could tell, but we can't reliably. */
|
||
if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP)
|
||
{
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: stepping_past_singlestep_breakpoint\n");
|
||
/* Pull the single step breakpoints out of the target. */
|
||
remove_single_step_breakpoints ();
|
||
singlestep_breakpoints_inserted_p = 0;
|
||
|
||
ecs->random_signal = 0;
|
||
|
||
context_switch (saved_singlestep_ptid);
|
||
if (deprecated_context_hook)
|
||
deprecated_context_hook (pid_to_thread_id (ecs->ptid));
|
||
|
||
resume (1, TARGET_SIGNAL_0);
|
||
prepare_to_wait (ecs);
|
||
return;
|
||
}
|
||
}
|
||
|
||
stepping_past_singlestep_breakpoint = 0;
|
||
|
||
if (!ptid_equal (deferred_step_ptid, null_ptid))
|
||
{
|
||
/* In non-stop mode, there's never a deferred_step_ptid set. */
|
||
gdb_assert (!non_stop);
|
||
|
||
/* If we stopped for some other reason than single-stepping, ignore
|
||
the fact that we were supposed to switch back. */
|
||
if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP)
|
||
{
|
||
struct thread_info *tp;
|
||
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"infrun: handling deferred step\n");
|
||
|
||
/* Pull the single step breakpoints out of the target. */
|
||
if (singlestep_breakpoints_inserted_p)
|
||
{
|
||
remove_single_step_breakpoints ();
|
||
singlestep_breakpoints_inserted_p = 0;
|
||
}
|
||
|
||
/* Note: We do not call context_switch at this point, as the
|
||
context is already set up for stepping the original thread. */
|
||
switch_to_thread (deferred_step_ptid);
|
||
deferred_step_ptid = null_ptid;
|
||
/* Suppress spurious "Switching to ..." message. */
|
||
previous_inferior_ptid = inferior_ptid;
|
||
|
||
resume (1, TARGET_SIGNAL_0);
|
||
prepare_to_wait (ecs);
|
||
return;
|
||
}
|
||
|
||
deferred_step_ptid = null_ptid;
|
||
}
|
||
|
||
/* See if a thread hit a thread-specific breakpoint that was meant for
|
||
another thread. If so, then step that thread past the breakpoint,
|
||
and continue it. */
|
||
|
||
if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP)
|
||
{
|
||
int thread_hop_needed = 0;
|
||
|
||
/* Check if a regular breakpoint has been hit before checking
|
||
for a potential single step breakpoint. Otherwise, GDB will
|
||
not see this breakpoint hit when stepping onto breakpoints. */
|
||
if (regular_breakpoint_inserted_here_p (stop_pc))
|
||
{
|
||
ecs->random_signal = 0;
|
||
if (!breakpoint_thread_match (stop_pc, ecs->ptid))
|
||
thread_hop_needed = 1;
|
||
}
|
||
else if (singlestep_breakpoints_inserted_p)
|
||
{
|
||
/* We have not context switched yet, so this should be true
|
||
no matter which thread hit the singlestep breakpoint. */
|
||
gdb_assert (ptid_equal (inferior_ptid, singlestep_ptid));
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: software single step "
|
||
"trap for %s\n",
|
||
target_pid_to_str (ecs->ptid));
|
||
|
||
ecs->random_signal = 0;
|
||
/* The call to in_thread_list is necessary because PTIDs sometimes
|
||
change when we go from single-threaded to multi-threaded. If
|
||
the singlestep_ptid is still in the list, assume that it is
|
||
really different from ecs->ptid. */
|
||
if (!ptid_equal (singlestep_ptid, ecs->ptid)
|
||
&& in_thread_list (singlestep_ptid))
|
||
{
|
||
/* If the PC of the thread we were trying to single-step
|
||
has changed, discard this event (which we were going
|
||
to ignore anyway), and pretend we saw that thread
|
||
trap. This prevents us continuously moving the
|
||
single-step breakpoint forward, one instruction at a
|
||
time. If the PC has changed, then the thread we were
|
||
trying to single-step has trapped or been signalled,
|
||
but the event has not been reported to GDB yet.
|
||
|
||
There might be some cases where this loses signal
|
||
information, if a signal has arrived at exactly the
|
||
same time that the PC changed, but this is the best
|
||
we can do with the information available. Perhaps we
|
||
should arrange to report all events for all threads
|
||
when they stop, or to re-poll the remote looking for
|
||
this particular thread (i.e. temporarily enable
|
||
schedlock). */
|
||
|
||
CORE_ADDR new_singlestep_pc
|
||
= regcache_read_pc (get_thread_regcache (singlestep_ptid));
|
||
|
||
if (new_singlestep_pc != singlestep_pc)
|
||
{
|
||
enum target_signal stop_signal;
|
||
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: unexpected thread,"
|
||
" but expected thread advanced also\n");
|
||
|
||
/* The current context still belongs to
|
||
singlestep_ptid. Don't swap here, since that's
|
||
the context we want to use. Just fudge our
|
||
state and continue. */
|
||
stop_signal = ecs->event_thread->stop_signal;
|
||
ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
|
||
ecs->ptid = singlestep_ptid;
|
||
ecs->event_thread = find_thread_pid (ecs->ptid);
|
||
ecs->event_thread->stop_signal = stop_signal;
|
||
stop_pc = new_singlestep_pc;
|
||
}
|
||
else
|
||
{
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"infrun: unexpected thread\n");
|
||
|
||
thread_hop_needed = 1;
|
||
stepping_past_singlestep_breakpoint = 1;
|
||
saved_singlestep_ptid = singlestep_ptid;
|
||
}
|
||
}
|
||
}
|
||
|
||
if (thread_hop_needed)
|
||
{
|
||
int remove_status = 0;
|
||
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: thread_hop_needed\n");
|
||
|
||
/* Saw a breakpoint, but it was hit by the wrong thread.
|
||
Just continue. */
|
||
|
||
if (singlestep_breakpoints_inserted_p)
|
||
{
|
||
/* Pull the single step breakpoints out of the target. */
|
||
remove_single_step_breakpoints ();
|
||
singlestep_breakpoints_inserted_p = 0;
|
||
}
|
||
|
||
/* If the arch can displace step, don't remove the
|
||
breakpoints. */
|
||
if (!use_displaced_stepping (current_gdbarch))
|
||
remove_status = remove_breakpoints ();
|
||
|
||
/* Did we fail to remove breakpoints? If so, try
|
||
to set the PC past the bp. (There's at least
|
||
one situation in which we can fail to remove
|
||
the bp's: On HP-UX's that use ttrace, we can't
|
||
change the address space of a vforking child
|
||
process until the child exits (well, okay, not
|
||
then either :-) or execs. */
|
||
if (remove_status != 0)
|
||
error (_("Cannot step over breakpoint hit in wrong thread"));
|
||
else
|
||
{ /* Single step */
|
||
if (!ptid_equal (inferior_ptid, ecs->ptid))
|
||
context_switch (ecs->ptid);
|
||
|
||
if (!non_stop)
|
||
{
|
||
/* Only need to require the next event from this
|
||
thread in all-stop mode. */
|
||
waiton_ptid = ecs->ptid;
|
||
infwait_state = infwait_thread_hop_state;
|
||
}
|
||
|
||
ecs->event_thread->stepping_over_breakpoint = 1;
|
||
keep_going (ecs);
|
||
registers_changed ();
|
||
return;
|
||
}
|
||
}
|
||
else if (singlestep_breakpoints_inserted_p)
|
||
{
|
||
sw_single_step_trap_p = 1;
|
||
ecs->random_signal = 0;
|
||
}
|
||
}
|
||
else
|
||
ecs->random_signal = 1;
|
||
|
||
/* See if something interesting happened to the non-current thread. If
|
||
so, then switch to that thread. */
|
||
if (!ptid_equal (ecs->ptid, inferior_ptid))
|
||
{
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: context switch\n");
|
||
|
||
context_switch (ecs->ptid);
|
||
|
||
if (deprecated_context_hook)
|
||
deprecated_context_hook (pid_to_thread_id (ecs->ptid));
|
||
}
|
||
|
||
if (singlestep_breakpoints_inserted_p)
|
||
{
|
||
/* Pull the single step breakpoints out of the target. */
|
||
remove_single_step_breakpoints ();
|
||
singlestep_breakpoints_inserted_p = 0;
|
||
}
|
||
|
||
if (stepped_after_stopped_by_watchpoint)
|
||
stopped_by_watchpoint = 0;
|
||
else
|
||
stopped_by_watchpoint = watchpoints_triggered (&ecs->ws);
|
||
|
||
/* If necessary, step over this watchpoint. We'll be back to display
|
||
it in a moment. */
|
||
if (stopped_by_watchpoint
|
||
&& (HAVE_STEPPABLE_WATCHPOINT
|
||
|| gdbarch_have_nonsteppable_watchpoint (current_gdbarch)))
|
||
{
|
||
/* At this point, we are stopped at an instruction which has
|
||
attempted to write to a piece of memory under control of
|
||
a watchpoint. The instruction hasn't actually executed
|
||
yet. If we were to evaluate the watchpoint expression
|
||
now, we would get the old value, and therefore no change
|
||
would seem to have occurred.
|
||
|
||
In order to make watchpoints work `right', we really need
|
||
to complete the memory write, and then evaluate the
|
||
watchpoint expression. We do this by single-stepping the
|
||
target.
|
||
|
||
It may not be necessary to disable the watchpoint to stop over
|
||
it. For example, the PA can (with some kernel cooperation)
|
||
single step over a watchpoint without disabling the watchpoint.
|
||
|
||
It is far more common to need to disable a watchpoint to step
|
||
the inferior over it. If we have non-steppable watchpoints,
|
||
we must disable the current watchpoint; it's simplest to
|
||
disable all watchpoints and breakpoints. */
|
||
|
||
if (!HAVE_STEPPABLE_WATCHPOINT)
|
||
remove_breakpoints ();
|
||
registers_changed ();
|
||
target_resume (ecs->ptid, 1, TARGET_SIGNAL_0); /* Single step */
|
||
waiton_ptid = ecs->ptid;
|
||
if (HAVE_STEPPABLE_WATCHPOINT)
|
||
infwait_state = infwait_step_watch_state;
|
||
else
|
||
infwait_state = infwait_nonstep_watch_state;
|
||
prepare_to_wait (ecs);
|
||
return;
|
||
}
|
||
|
||
ecs->stop_func_start = 0;
|
||
ecs->stop_func_end = 0;
|
||
ecs->stop_func_name = 0;
|
||
/* Don't care about return value; stop_func_start and stop_func_name
|
||
will both be 0 if it doesn't work. */
|
||
find_pc_partial_function (stop_pc, &ecs->stop_func_name,
|
||
&ecs->stop_func_start, &ecs->stop_func_end);
|
||
ecs->stop_func_start
|
||
+= gdbarch_deprecated_function_start_offset (current_gdbarch);
|
||
ecs->event_thread->stepping_over_breakpoint = 0;
|
||
bpstat_clear (&ecs->event_thread->stop_bpstat);
|
||
ecs->event_thread->stop_step = 0;
|
||
stop_print_frame = 1;
|
||
ecs->random_signal = 0;
|
||
stopped_by_random_signal = 0;
|
||
|
||
if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP
|
||
&& ecs->event_thread->trap_expected
|
||
&& gdbarch_single_step_through_delay_p (current_gdbarch)
|
||
&& currently_stepping (ecs->event_thread))
|
||
{
|
||
/* We're trying to step off a breakpoint. Turns out that we're
|
||
also on an instruction that needs to be stepped multiple
|
||
times before it's been fully executing. E.g., architectures
|
||
with a delay slot. It needs to be stepped twice, once for
|
||
the instruction and once for the delay slot. */
|
||
int step_through_delay
|
||
= gdbarch_single_step_through_delay (current_gdbarch,
|
||
get_current_frame ());
|
||
if (debug_infrun && step_through_delay)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: step through delay\n");
|
||
if (ecs->event_thread->step_range_end == 0 && step_through_delay)
|
||
{
|
||
/* The user issued a continue when stopped at a breakpoint.
|
||
Set up for another trap and get out of here. */
|
||
ecs->event_thread->stepping_over_breakpoint = 1;
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
else if (step_through_delay)
|
||
{
|
||
/* The user issued a step when stopped at a breakpoint.
|
||
Maybe we should stop, maybe we should not - the delay
|
||
slot *might* correspond to a line of source. In any
|
||
case, don't decide that here, just set
|
||
ecs->stepping_over_breakpoint, making sure we
|
||
single-step again before breakpoints are re-inserted. */
|
||
ecs->event_thread->stepping_over_breakpoint = 1;
|
||
}
|
||
}
|
||
|
||
/* Look at the cause of the stop, and decide what to do.
|
||
The alternatives are:
|
||
1) stop_stepping and return; to really stop and return to the debugger,
|
||
2) keep_going and return to start up again
|
||
(set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
|
||
3) set ecs->random_signal to 1, and the decision between 1 and 2
|
||
will be made according to the signal handling tables. */
|
||
|
||
/* First, distinguish signals caused by the debugger from signals
|
||
that have to do with the program's own actions. Note that
|
||
breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
|
||
on the operating system version. Here we detect when a SIGILL or
|
||
SIGEMT is really a breakpoint and change it to SIGTRAP. We do
|
||
something similar for SIGSEGV, since a SIGSEGV will be generated
|
||
when we're trying to execute a breakpoint instruction on a
|
||
non-executable stack. This happens for call dummy breakpoints
|
||
for architectures like SPARC that place call dummies on the
|
||
stack.
|
||
|
||
If we're doing a displaced step past a breakpoint, then the
|
||
breakpoint is always inserted at the original instruction;
|
||
non-standard signals can't be explained by the breakpoint. */
|
||
if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP
|
||
|| (! ecs->event_thread->trap_expected
|
||
&& breakpoint_inserted_here_p (stop_pc)
|
||
&& (ecs->event_thread->stop_signal == TARGET_SIGNAL_ILL
|
||
|| ecs->event_thread->stop_signal == TARGET_SIGNAL_SEGV
|
||
|| ecs->event_thread->stop_signal == TARGET_SIGNAL_EMT))
|
||
|| stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_NO_SIGSTOP
|
||
|| stop_soon == STOP_QUIETLY_REMOTE)
|
||
{
|
||
if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP && stop_after_trap)
|
||
{
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: stopped\n");
|
||
stop_print_frame = 0;
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
|
||
/* This is originated from start_remote(), start_inferior() and
|
||
shared libraries hook functions. */
|
||
if (stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_REMOTE)
|
||
{
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: quietly stopped\n");
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
|
||
/* This originates from attach_command(). We need to overwrite
|
||
the stop_signal here, because some kernels don't ignore a
|
||
SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
|
||
See more comments in inferior.h. On the other hand, if we
|
||
get a non-SIGSTOP, report it to the user - assume the backend
|
||
will handle the SIGSTOP if it should show up later.
|
||
|
||
Also consider that the attach is complete when we see a
|
||
SIGTRAP. Some systems (e.g. Windows), and stubs supporting
|
||
target extended-remote report it instead of a SIGSTOP
|
||
(e.g. gdbserver). We already rely on SIGTRAP being our
|
||
signal, so this is no exception. */
|
||
if (stop_soon == STOP_QUIETLY_NO_SIGSTOP
|
||
&& (ecs->event_thread->stop_signal == TARGET_SIGNAL_STOP
|
||
|| ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP))
|
||
{
|
||
stop_stepping (ecs);
|
||
ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
|
||
return;
|
||
}
|
||
|
||
/* See if there is a breakpoint at the current PC. */
|
||
ecs->event_thread->stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid);
|
||
|
||
/* Following in case break condition called a
|
||
function. */
|
||
stop_print_frame = 1;
|
||
|
||
/* NOTE: cagney/2003-03-29: These two checks for a random signal
|
||
at one stage in the past included checks for an inferior
|
||
function call's call dummy's return breakpoint. The original
|
||
comment, that went with the test, read:
|
||
|
||
``End of a stack dummy. Some systems (e.g. Sony news) give
|
||
another signal besides SIGTRAP, so check here as well as
|
||
above.''
|
||
|
||
If someone ever tries to get call dummys on a
|
||
non-executable stack to work (where the target would stop
|
||
with something like a SIGSEGV), then those tests might need
|
||
to be re-instated. Given, however, that the tests were only
|
||
enabled when momentary breakpoints were not being used, I
|
||
suspect that it won't be the case.
|
||
|
||
NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
|
||
be necessary for call dummies on a non-executable stack on
|
||
SPARC. */
|
||
|
||
if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP)
|
||
ecs->random_signal
|
||
= !(bpstat_explains_signal (ecs->event_thread->stop_bpstat)
|
||
|| ecs->event_thread->trap_expected
|
||
|| (ecs->event_thread->step_range_end
|
||
&& ecs->event_thread->step_resume_breakpoint == NULL));
|
||
else
|
||
{
|
||
ecs->random_signal = !bpstat_explains_signal (ecs->event_thread->stop_bpstat);
|
||
if (!ecs->random_signal)
|
||
ecs->event_thread->stop_signal = TARGET_SIGNAL_TRAP;
|
||
}
|
||
}
|
||
|
||
/* When we reach this point, we've pretty much decided
|
||
that the reason for stopping must've been a random
|
||
(unexpected) signal. */
|
||
|
||
else
|
||
ecs->random_signal = 1;
|
||
|
||
process_event_stop_test:
|
||
/* For the program's own signals, act according to
|
||
the signal handling tables. */
|
||
|
||
if (ecs->random_signal)
|
||
{
|
||
/* Signal not for debugging purposes. */
|
||
int printed = 0;
|
||
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: random signal %d\n",
|
||
ecs->event_thread->stop_signal);
|
||
|
||
stopped_by_random_signal = 1;
|
||
|
||
if (signal_print[ecs->event_thread->stop_signal])
|
||
{
|
||
printed = 1;
|
||
target_terminal_ours_for_output ();
|
||
print_stop_reason (SIGNAL_RECEIVED, ecs->event_thread->stop_signal);
|
||
}
|
||
/* Always stop on signals if we're either just gaining control
|
||
of the program, or the user explicitly requested this thread
|
||
to remain stopped. */
|
||
if (stop_soon != NO_STOP_QUIETLY
|
||
|| ecs->event_thread->stop_requested
|
||
|| signal_stop_state (ecs->event_thread->stop_signal))
|
||
{
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
/* If not going to stop, give terminal back
|
||
if we took it away. */
|
||
else if (printed)
|
||
target_terminal_inferior ();
|
||
|
||
/* Clear the signal if it should not be passed. */
|
||
if (signal_program[ecs->event_thread->stop_signal] == 0)
|
||
ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
|
||
|
||
if (ecs->event_thread->prev_pc == read_pc ()
|
||
&& ecs->event_thread->trap_expected
|
||
&& ecs->event_thread->step_resume_breakpoint == NULL)
|
||
{
|
||
/* We were just starting a new sequence, attempting to
|
||
single-step off of a breakpoint and expecting a SIGTRAP.
|
||
Instead this signal arrives. This signal will take us out
|
||
of the stepping range so GDB needs to remember to, when
|
||
the signal handler returns, resume stepping off that
|
||
breakpoint. */
|
||
/* To simplify things, "continue" is forced to use the same
|
||
code paths as single-step - set a breakpoint at the
|
||
signal return address and then, once hit, step off that
|
||
breakpoint. */
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"infrun: signal arrived while stepping over "
|
||
"breakpoint\n");
|
||
|
||
insert_step_resume_breakpoint_at_frame (get_current_frame ());
|
||
ecs->event_thread->step_after_step_resume_breakpoint = 1;
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
|
||
if (ecs->event_thread->step_range_end != 0
|
||
&& ecs->event_thread->stop_signal != TARGET_SIGNAL_0
|
||
&& (ecs->event_thread->step_range_start <= stop_pc
|
||
&& stop_pc < ecs->event_thread->step_range_end)
|
||
&& frame_id_eq (get_frame_id (get_current_frame ()),
|
||
ecs->event_thread->step_frame_id)
|
||
&& ecs->event_thread->step_resume_breakpoint == NULL)
|
||
{
|
||
/* The inferior is about to take a signal that will take it
|
||
out of the single step range. Set a breakpoint at the
|
||
current PC (which is presumably where the signal handler
|
||
will eventually return) and then allow the inferior to
|
||
run free.
|
||
|
||
Note that this is only needed for a signal delivered
|
||
while in the single-step range. Nested signals aren't a
|
||
problem as they eventually all return. */
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"infrun: signal may take us out of "
|
||
"single-step range\n");
|
||
|
||
insert_step_resume_breakpoint_at_frame (get_current_frame ());
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
|
||
/* Note: step_resume_breakpoint may be non-NULL. This occures
|
||
when either there's a nested signal, or when there's a
|
||
pending signal enabled just as the signal handler returns
|
||
(leaving the inferior at the step-resume-breakpoint without
|
||
actually executing it). Either way continue until the
|
||
breakpoint is really hit. */
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
|
||
/* Handle cases caused by hitting a breakpoint. */
|
||
{
|
||
CORE_ADDR jmp_buf_pc;
|
||
struct bpstat_what what;
|
||
|
||
what = bpstat_what (ecs->event_thread->stop_bpstat);
|
||
|
||
if (what.call_dummy)
|
||
{
|
||
stop_stack_dummy = 1;
|
||
}
|
||
|
||
switch (what.main_action)
|
||
{
|
||
case BPSTAT_WHAT_SET_LONGJMP_RESUME:
|
||
/* If we hit the breakpoint at longjmp while stepping, we
|
||
install a momentary breakpoint at the target of the
|
||
jmp_buf. */
|
||
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
|
||
|
||
ecs->event_thread->stepping_over_breakpoint = 1;
|
||
|
||
if (!gdbarch_get_longjmp_target_p (current_gdbarch)
|
||
|| !gdbarch_get_longjmp_target (current_gdbarch,
|
||
get_current_frame (), &jmp_buf_pc))
|
||
{
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "\
|
||
infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME (!gdbarch_get_longjmp_target)\n");
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
|
||
/* We're going to replace the current step-resume breakpoint
|
||
with a longjmp-resume breakpoint. */
|
||
delete_step_resume_breakpoint (ecs->event_thread);
|
||
|
||
/* Insert a breakpoint at resume address. */
|
||
insert_longjmp_resume_breakpoint (jmp_buf_pc);
|
||
|
||
keep_going (ecs);
|
||
return;
|
||
|
||
case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
|
||
|
||
gdb_assert (ecs->event_thread->step_resume_breakpoint != NULL);
|
||
delete_step_resume_breakpoint (ecs->event_thread);
|
||
|
||
ecs->event_thread->stop_step = 1;
|
||
print_stop_reason (END_STEPPING_RANGE, 0);
|
||
stop_stepping (ecs);
|
||
return;
|
||
|
||
case BPSTAT_WHAT_SINGLE:
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_SINGLE\n");
|
||
ecs->event_thread->stepping_over_breakpoint = 1;
|
||
/* Still need to check other stuff, at least the case
|
||
where we are stepping and step out of the right range. */
|
||
break;
|
||
|
||
case BPSTAT_WHAT_STOP_NOISY:
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
|
||
stop_print_frame = 1;
|
||
|
||
/* We are about to nuke the step_resume_breakpointt via the
|
||
cleanup chain, so no need to worry about it here. */
|
||
|
||
stop_stepping (ecs);
|
||
return;
|
||
|
||
case BPSTAT_WHAT_STOP_SILENT:
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
|
||
stop_print_frame = 0;
|
||
|
||
/* We are about to nuke the step_resume_breakpoin via the
|
||
cleanup chain, so no need to worry about it here. */
|
||
|
||
stop_stepping (ecs);
|
||
return;
|
||
|
||
case BPSTAT_WHAT_STEP_RESUME:
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
|
||
|
||
delete_step_resume_breakpoint (ecs->event_thread);
|
||
if (ecs->event_thread->step_after_step_resume_breakpoint)
|
||
{
|
||
/* Back when the step-resume breakpoint was inserted, we
|
||
were trying to single-step off a breakpoint. Go back
|
||
to doing that. */
|
||
ecs->event_thread->step_after_step_resume_breakpoint = 0;
|
||
ecs->event_thread->stepping_over_breakpoint = 1;
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
if (stop_pc == ecs->stop_func_start
|
||
&& execution_direction == EXEC_REVERSE)
|
||
{
|
||
/* We are stepping over a function call in reverse, and
|
||
just hit the step-resume breakpoint at the start
|
||
address of the function. Go back to single-stepping,
|
||
which should take us back to the function call. */
|
||
ecs->event_thread->stepping_over_breakpoint = 1;
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
break;
|
||
|
||
case BPSTAT_WHAT_CHECK_SHLIBS:
|
||
case BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK:
|
||
{
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_CHECK_SHLIBS\n");
|
||
|
||
/* Check for any newly added shared libraries if we're
|
||
supposed to be adding them automatically. Switch
|
||
terminal for any messages produced by
|
||
breakpoint_re_set. */
|
||
target_terminal_ours_for_output ();
|
||
/* NOTE: cagney/2003-11-25: Make certain that the target
|
||
stack's section table is kept up-to-date. Architectures,
|
||
(e.g., PPC64), use the section table to perform
|
||
operations such as address => section name and hence
|
||
require the table to contain all sections (including
|
||
those found in shared libraries). */
|
||
/* NOTE: cagney/2003-11-25: Pass current_target and not
|
||
exec_ops to SOLIB_ADD. This is because current GDB is
|
||
only tooled to propagate section_table changes out from
|
||
the "current_target" (see target_resize_to_sections), and
|
||
not up from the exec stratum. This, of course, isn't
|
||
right. "infrun.c" should only interact with the
|
||
exec/process stratum, instead relying on the target stack
|
||
to propagate relevant changes (stop, section table
|
||
changed, ...) up to other layers. */
|
||
#ifdef SOLIB_ADD
|
||
SOLIB_ADD (NULL, 0, ¤t_target, auto_solib_add);
|
||
#else
|
||
solib_add (NULL, 0, ¤t_target, auto_solib_add);
|
||
#endif
|
||
target_terminal_inferior ();
|
||
|
||
/* If requested, stop when the dynamic linker notifies
|
||
gdb of events. This allows the user to get control
|
||
and place breakpoints in initializer routines for
|
||
dynamically loaded objects (among other things). */
|
||
if (stop_on_solib_events || stop_stack_dummy)
|
||
{
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
|
||
/* If we stopped due to an explicit catchpoint, then the
|
||
(see above) call to SOLIB_ADD pulled in any symbols
|
||
from a newly-loaded library, if appropriate.
|
||
|
||
We do want the inferior to stop, but not where it is
|
||
now, which is in the dynamic linker callback. Rather,
|
||
we would like it stop in the user's program, just after
|
||
the call that caused this catchpoint to trigger. That
|
||
gives the user a more useful vantage from which to
|
||
examine their program's state. */
|
||
else if (what.main_action
|
||
== BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK)
|
||
{
|
||
/* ??rehrauer: If I could figure out how to get the
|
||
right return PC from here, we could just set a temp
|
||
breakpoint and resume. I'm not sure we can without
|
||
cracking open the dld's shared libraries and sniffing
|
||
their unwind tables and text/data ranges, and that's
|
||
not a terribly portable notion.
|
||
|
||
Until that time, we must step the inferior out of the
|
||
dld callback, and also out of the dld itself (and any
|
||
code or stubs in libdld.sl, such as "shl_load" and
|
||
friends) until we reach non-dld code. At that point,
|
||
we can stop stepping. */
|
||
bpstat_get_triggered_catchpoints (ecs->event_thread->stop_bpstat,
|
||
&ecs->
|
||
event_thread->
|
||
stepping_through_solib_catchpoints);
|
||
ecs->event_thread->stepping_through_solib_after_catch = 1;
|
||
|
||
/* Be sure to lift all breakpoints, so the inferior does
|
||
actually step past this point... */
|
||
ecs->event_thread->stepping_over_breakpoint = 1;
|
||
break;
|
||
}
|
||
else
|
||
{
|
||
/* We want to step over this breakpoint, then keep going. */
|
||
ecs->event_thread->stepping_over_breakpoint = 1;
|
||
break;
|
||
}
|
||
}
|
||
break;
|
||
|
||
case BPSTAT_WHAT_LAST:
|
||
/* Not a real code, but listed here to shut up gcc -Wall. */
|
||
|
||
case BPSTAT_WHAT_KEEP_CHECKING:
|
||
break;
|
||
}
|
||
}
|
||
|
||
/* We come here if we hit a breakpoint but should not
|
||
stop for it. Possibly we also were stepping
|
||
and should stop for that. So fall through and
|
||
test for stepping. But, if not stepping,
|
||
do not stop. */
|
||
|
||
/* Are we stepping to get the inferior out of the dynamic linker's
|
||
hook (and possibly the dld itself) after catching a shlib
|
||
event? */
|
||
if (ecs->event_thread->stepping_through_solib_after_catch)
|
||
{
|
||
#if defined(SOLIB_ADD)
|
||
/* Have we reached our destination? If not, keep going. */
|
||
if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs->ptid), stop_pc))
|
||
{
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: stepping in dynamic linker\n");
|
||
ecs->event_thread->stepping_over_breakpoint = 1;
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
#endif
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: step past dynamic linker\n");
|
||
/* Else, stop and report the catchpoint(s) whose triggering
|
||
caused us to begin stepping. */
|
||
ecs->event_thread->stepping_through_solib_after_catch = 0;
|
||
bpstat_clear (&ecs->event_thread->stop_bpstat);
|
||
ecs->event_thread->stop_bpstat
|
||
= bpstat_copy (ecs->event_thread->stepping_through_solib_catchpoints);
|
||
bpstat_clear (&ecs->event_thread->stepping_through_solib_catchpoints);
|
||
stop_print_frame = 1;
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
|
||
if (ecs->event_thread->step_resume_breakpoint)
|
||
{
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"infrun: step-resume breakpoint is inserted\n");
|
||
|
||
/* Having a step-resume breakpoint overrides anything
|
||
else having to do with stepping commands until
|
||
that breakpoint is reached. */
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
|
||
if (ecs->event_thread->step_range_end == 0)
|
||
{
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: no stepping, continue\n");
|
||
/* Likewise if we aren't even stepping. */
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
|
||
/* If stepping through a line, keep going if still within it.
|
||
|
||
Note that step_range_end is the address of the first instruction
|
||
beyond the step range, and NOT the address of the last instruction
|
||
within it! */
|
||
if (stop_pc >= ecs->event_thread->step_range_start
|
||
&& stop_pc < ecs->event_thread->step_range_end)
|
||
{
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: stepping inside range [0x%s-0x%s]\n",
|
||
paddr_nz (ecs->event_thread->step_range_start),
|
||
paddr_nz (ecs->event_thread->step_range_end));
|
||
|
||
/* When stepping backward, stop at beginning of line range
|
||
(unless it's the function entry point, in which case
|
||
keep going back to the call point). */
|
||
if (stop_pc == ecs->event_thread->step_range_start
|
||
&& stop_pc != ecs->stop_func_start
|
||
&& execution_direction == EXEC_REVERSE)
|
||
{
|
||
ecs->event_thread->stop_step = 1;
|
||
print_stop_reason (END_STEPPING_RANGE, 0);
|
||
stop_stepping (ecs);
|
||
}
|
||
else
|
||
keep_going (ecs);
|
||
|
||
return;
|
||
}
|
||
|
||
/* We stepped out of the stepping range. */
|
||
|
||
/* If we are stepping at the source level and entered the runtime
|
||
loader dynamic symbol resolution code, we keep on single stepping
|
||
until we exit the run time loader code and reach the callee's
|
||
address. */
|
||
if (ecs->event_thread->step_over_calls == STEP_OVER_UNDEBUGGABLE
|
||
&& in_solib_dynsym_resolve_code (stop_pc))
|
||
{
|
||
CORE_ADDR pc_after_resolver =
|
||
gdbarch_skip_solib_resolver (current_gdbarch, stop_pc);
|
||
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: stepped into dynsym resolve code\n");
|
||
|
||
if (pc_after_resolver)
|
||
{
|
||
/* Set up a step-resume breakpoint at the address
|
||
indicated by SKIP_SOLIB_RESOLVER. */
|
||
struct symtab_and_line sr_sal;
|
||
init_sal (&sr_sal);
|
||
sr_sal.pc = pc_after_resolver;
|
||
|
||
insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
|
||
}
|
||
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
|
||
if (ecs->event_thread->step_range_end != 1
|
||
&& (ecs->event_thread->step_over_calls == STEP_OVER_UNDEBUGGABLE
|
||
|| ecs->event_thread->step_over_calls == STEP_OVER_ALL)
|
||
&& get_frame_type (get_current_frame ()) == SIGTRAMP_FRAME)
|
||
{
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: stepped into signal trampoline\n");
|
||
/* The inferior, while doing a "step" or "next", has ended up in
|
||
a signal trampoline (either by a signal being delivered or by
|
||
the signal handler returning). Just single-step until the
|
||
inferior leaves the trampoline (either by calling the handler
|
||
or returning). */
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
|
||
/* Check for subroutine calls. The check for the current frame
|
||
equalling the step ID is not necessary - the check of the
|
||
previous frame's ID is sufficient - but it is a common case and
|
||
cheaper than checking the previous frame's ID.
|
||
|
||
NOTE: frame_id_eq will never report two invalid frame IDs as
|
||
being equal, so to get into this block, both the current and
|
||
previous frame must have valid frame IDs. */
|
||
if (!frame_id_eq (get_frame_id (get_current_frame ()),
|
||
ecs->event_thread->step_frame_id)
|
||
&& (frame_id_eq (frame_unwind_id (get_current_frame ()),
|
||
ecs->event_thread->step_frame_id)
|
||
|| execution_direction == EXEC_REVERSE))
|
||
{
|
||
CORE_ADDR real_stop_pc;
|
||
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: stepped into subroutine\n");
|
||
|
||
if ((ecs->event_thread->step_over_calls == STEP_OVER_NONE)
|
||
|| ((ecs->event_thread->step_range_end == 1)
|
||
&& in_prologue (ecs->event_thread->prev_pc,
|
||
ecs->stop_func_start)))
|
||
{
|
||
/* I presume that step_over_calls is only 0 when we're
|
||
supposed to be stepping at the assembly language level
|
||
("stepi"). Just stop. */
|
||
/* Also, maybe we just did a "nexti" inside a prolog, so we
|
||
thought it was a subroutine call but it was not. Stop as
|
||
well. FENN */
|
||
ecs->event_thread->stop_step = 1;
|
||
print_stop_reason (END_STEPPING_RANGE, 0);
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
|
||
if (ecs->event_thread->step_over_calls == STEP_OVER_ALL)
|
||
{
|
||
/* We're doing a "next".
|
||
|
||
Normal (forward) execution: set a breakpoint at the
|
||
callee's return address (the address at which the caller
|
||
will resume).
|
||
|
||
Reverse (backward) execution. set the step-resume
|
||
breakpoint at the start of the function that we just
|
||
stepped into (backwards), and continue to there. When we
|
||
get there, we'll need to single-step back to the caller. */
|
||
|
||
if (execution_direction == EXEC_REVERSE)
|
||
{
|
||
struct symtab_and_line sr_sal;
|
||
|
||
if (ecs->stop_func_start == 0
|
||
&& in_solib_dynsym_resolve_code (stop_pc))
|
||
{
|
||
/* Stepped into runtime loader dynamic symbol
|
||
resolution code. Since we're in reverse,
|
||
we have already backed up through the runtime
|
||
loader and the dynamic function. This is just
|
||
the trampoline (jump table).
|
||
|
||
Just keep stepping, we'll soon be home.
|
||
*/
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
/* Normal (staticly linked) function call return. */
|
||
init_sal (&sr_sal);
|
||
sr_sal.pc = ecs->stop_func_start;
|
||
insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
|
||
}
|
||
else
|
||
insert_step_resume_breakpoint_at_caller (get_current_frame ());
|
||
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
|
||
/* If we are in a function call trampoline (a stub between the
|
||
calling routine and the real function), locate the real
|
||
function. That's what tells us (a) whether we want to step
|
||
into it at all, and (b) what prologue we want to run to the
|
||
end of, if we do step into it. */
|
||
real_stop_pc = skip_language_trampoline (get_current_frame (), stop_pc);
|
||
if (real_stop_pc == 0)
|
||
real_stop_pc = gdbarch_skip_trampoline_code
|
||
(current_gdbarch, get_current_frame (), stop_pc);
|
||
if (real_stop_pc != 0)
|
||
ecs->stop_func_start = real_stop_pc;
|
||
|
||
if (real_stop_pc != 0 && in_solib_dynsym_resolve_code (real_stop_pc))
|
||
{
|
||
struct symtab_and_line sr_sal;
|
||
init_sal (&sr_sal);
|
||
sr_sal.pc = ecs->stop_func_start;
|
||
|
||
insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
|
||
/* If we have line number information for the function we are
|
||
thinking of stepping into, step into it.
|
||
|
||
If there are several symtabs at that PC (e.g. with include
|
||
files), just want to know whether *any* of them have line
|
||
numbers. find_pc_line handles this. */
|
||
{
|
||
struct symtab_and_line tmp_sal;
|
||
|
||
tmp_sal = find_pc_line (ecs->stop_func_start, 0);
|
||
if (tmp_sal.line != 0)
|
||
{
|
||
if (execution_direction == EXEC_REVERSE)
|
||
handle_step_into_function_backward (ecs);
|
||
else
|
||
handle_step_into_function (ecs);
|
||
return;
|
||
}
|
||
}
|
||
|
||
/* If we have no line number and the step-stop-if-no-debug is
|
||
set, we stop the step so that the user has a chance to switch
|
||
in assembly mode. */
|
||
if (ecs->event_thread->step_over_calls == STEP_OVER_UNDEBUGGABLE
|
||
&& step_stop_if_no_debug)
|
||
{
|
||
ecs->event_thread->stop_step = 1;
|
||
print_stop_reason (END_STEPPING_RANGE, 0);
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
|
||
if (execution_direction == EXEC_REVERSE)
|
||
{
|
||
/* Set a breakpoint at callee's start address.
|
||
From there we can step once and be back in the caller. */
|
||
struct symtab_and_line sr_sal;
|
||
init_sal (&sr_sal);
|
||
sr_sal.pc = ecs->stop_func_start;
|
||
insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
|
||
}
|
||
else
|
||
/* Set a breakpoint at callee's return address (the address
|
||
at which the caller will resume). */
|
||
insert_step_resume_breakpoint_at_caller (get_current_frame ());
|
||
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
|
||
/* If we're in the return path from a shared library trampoline,
|
||
we want to proceed through the trampoline when stepping. */
|
||
if (gdbarch_in_solib_return_trampoline (current_gdbarch,
|
||
stop_pc, ecs->stop_func_name))
|
||
{
|
||
/* Determine where this trampoline returns. */
|
||
CORE_ADDR real_stop_pc;
|
||
real_stop_pc = gdbarch_skip_trampoline_code
|
||
(current_gdbarch, get_current_frame (), stop_pc);
|
||
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: stepped into solib return tramp\n");
|
||
|
||
/* Only proceed through if we know where it's going. */
|
||
if (real_stop_pc)
|
||
{
|
||
/* And put the step-breakpoint there and go until there. */
|
||
struct symtab_and_line sr_sal;
|
||
|
||
init_sal (&sr_sal); /* initialize to zeroes */
|
||
sr_sal.pc = real_stop_pc;
|
||
sr_sal.section = find_pc_overlay (sr_sal.pc);
|
||
|
||
/* Do not specify what the fp should be when we stop since
|
||
on some machines the prologue is where the new fp value
|
||
is established. */
|
||
insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
|
||
|
||
/* Restart without fiddling with the step ranges or
|
||
other state. */
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
}
|
||
|
||
stop_pc_sal = find_pc_line (stop_pc, 0);
|
||
|
||
/* NOTE: tausq/2004-05-24: This if block used to be done before all
|
||
the trampoline processing logic, however, there are some trampolines
|
||
that have no names, so we should do trampoline handling first. */
|
||
if (ecs->event_thread->step_over_calls == STEP_OVER_UNDEBUGGABLE
|
||
&& ecs->stop_func_name == NULL
|
||
&& stop_pc_sal.line == 0)
|
||
{
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: stepped into undebuggable function\n");
|
||
|
||
/* The inferior just stepped into, or returned to, an
|
||
undebuggable function (where there is no debugging information
|
||
and no line number corresponding to the address where the
|
||
inferior stopped). Since we want to skip this kind of code,
|
||
we keep going until the inferior returns from this
|
||
function - unless the user has asked us not to (via
|
||
set step-mode) or we no longer know how to get back
|
||
to the call site. */
|
||
if (step_stop_if_no_debug
|
||
|| !frame_id_p (frame_unwind_id (get_current_frame ())))
|
||
{
|
||
/* If we have no line number and the step-stop-if-no-debug
|
||
is set, we stop the step so that the user has a chance to
|
||
switch in assembly mode. */
|
||
ecs->event_thread->stop_step = 1;
|
||
print_stop_reason (END_STEPPING_RANGE, 0);
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
else
|
||
{
|
||
/* Set a breakpoint at callee's return address (the address
|
||
at which the caller will resume). */
|
||
insert_step_resume_breakpoint_at_caller (get_current_frame ());
|
||
keep_going (ecs);
|
||
return;
|
||
}
|
||
}
|
||
|
||
if (ecs->event_thread->step_range_end == 1)
|
||
{
|
||
/* It is stepi or nexti. We always want to stop stepping after
|
||
one instruction. */
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: stepi/nexti\n");
|
||
ecs->event_thread->stop_step = 1;
|
||
print_stop_reason (END_STEPPING_RANGE, 0);
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
|
||
if (stop_pc_sal.line == 0)
|
||
{
|
||
/* We have no line number information. That means to stop
|
||
stepping (does this always happen right after one instruction,
|
||
when we do "s" in a function with no line numbers,
|
||
or can this happen as a result of a return or longjmp?). */
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: no line number info\n");
|
||
ecs->event_thread->stop_step = 1;
|
||
print_stop_reason (END_STEPPING_RANGE, 0);
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
|
||
if ((stop_pc == stop_pc_sal.pc)
|
||
&& (ecs->event_thread->current_line != stop_pc_sal.line
|
||
|| ecs->event_thread->current_symtab != stop_pc_sal.symtab))
|
||
{
|
||
/* We are at the start of a different line. So stop. Note that
|
||
we don't stop if we step into the middle of a different line.
|
||
That is said to make things like for (;;) statements work
|
||
better. */
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: stepped to a different line\n");
|
||
ecs->event_thread->stop_step = 1;
|
||
print_stop_reason (END_STEPPING_RANGE, 0);
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
|
||
/* We aren't done stepping.
|
||
|
||
Optimize by setting the stepping range to the line.
|
||
(We might not be in the original line, but if we entered a
|
||
new line in mid-statement, we continue stepping. This makes
|
||
things like for(;;) statements work better.) */
|
||
|
||
ecs->event_thread->step_range_start = stop_pc_sal.pc;
|
||
ecs->event_thread->step_range_end = stop_pc_sal.end;
|
||
ecs->event_thread->step_frame_id = get_frame_id (get_current_frame ());
|
||
ecs->event_thread->current_line = stop_pc_sal.line;
|
||
ecs->event_thread->current_symtab = stop_pc_sal.symtab;
|
||
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: keep going\n");
|
||
keep_going (ecs);
|
||
}
|
||
|
||
/* Are we in the middle of stepping? */
|
||
|
||
static int
|
||
currently_stepping (struct thread_info *tp)
|
||
{
|
||
return (((tp->step_range_end && tp->step_resume_breakpoint == NULL)
|
||
|| tp->trap_expected)
|
||
|| tp->stepping_through_solib_after_catch
|
||
|| bpstat_should_step ());
|
||
}
|
||
|
||
/* Inferior has stepped into a subroutine call with source code that
|
||
we should not step over. Do step to the first line of code in
|
||
it. */
|
||
|
||
static void
|
||
handle_step_into_function (struct execution_control_state *ecs)
|
||
{
|
||
struct symtab *s;
|
||
struct symtab_and_line stop_func_sal, sr_sal;
|
||
|
||
s = find_pc_symtab (stop_pc);
|
||
if (s && s->language != language_asm)
|
||
ecs->stop_func_start = gdbarch_skip_prologue (current_gdbarch,
|
||
ecs->stop_func_start);
|
||
|
||
stop_func_sal = find_pc_line (ecs->stop_func_start, 0);
|
||
/* Use the step_resume_break to step until the end of the prologue,
|
||
even if that involves jumps (as it seems to on the vax under
|
||
4.2). */
|
||
/* If the prologue ends in the middle of a source line, continue to
|
||
the end of that source line (if it is still within the function).
|
||
Otherwise, just go to end of prologue. */
|
||
if (stop_func_sal.end
|
||
&& stop_func_sal.pc != ecs->stop_func_start
|
||
&& stop_func_sal.end < ecs->stop_func_end)
|
||
ecs->stop_func_start = stop_func_sal.end;
|
||
|
||
/* Architectures which require breakpoint adjustment might not be able
|
||
to place a breakpoint at the computed address. If so, the test
|
||
``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
|
||
ecs->stop_func_start to an address at which a breakpoint may be
|
||
legitimately placed.
|
||
|
||
Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
|
||
made, GDB will enter an infinite loop when stepping through
|
||
optimized code consisting of VLIW instructions which contain
|
||
subinstructions corresponding to different source lines. On
|
||
FR-V, it's not permitted to place a breakpoint on any but the
|
||
first subinstruction of a VLIW instruction. When a breakpoint is
|
||
set, GDB will adjust the breakpoint address to the beginning of
|
||
the VLIW instruction. Thus, we need to make the corresponding
|
||
adjustment here when computing the stop address. */
|
||
|
||
if (gdbarch_adjust_breakpoint_address_p (current_gdbarch))
|
||
{
|
||
ecs->stop_func_start
|
||
= gdbarch_adjust_breakpoint_address (current_gdbarch,
|
||
ecs->stop_func_start);
|
||
}
|
||
|
||
if (ecs->stop_func_start == stop_pc)
|
||
{
|
||
/* We are already there: stop now. */
|
||
ecs->event_thread->stop_step = 1;
|
||
print_stop_reason (END_STEPPING_RANGE, 0);
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
else
|
||
{
|
||
/* Put the step-breakpoint there and go until there. */
|
||
init_sal (&sr_sal); /* initialize to zeroes */
|
||
sr_sal.pc = ecs->stop_func_start;
|
||
sr_sal.section = find_pc_overlay (ecs->stop_func_start);
|
||
|
||
/* Do not specify what the fp should be when we stop since on
|
||
some machines the prologue is where the new fp value is
|
||
established. */
|
||
insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
|
||
|
||
/* And make sure stepping stops right away then. */
|
||
ecs->event_thread->step_range_end = ecs->event_thread->step_range_start;
|
||
}
|
||
keep_going (ecs);
|
||
}
|
||
|
||
/* Inferior has stepped backward into a subroutine call with source
|
||
code that we should not step over. Do step to the beginning of the
|
||
last line of code in it. */
|
||
|
||
static void
|
||
handle_step_into_function_backward (struct execution_control_state *ecs)
|
||
{
|
||
struct symtab *s;
|
||
struct symtab_and_line stop_func_sal, sr_sal;
|
||
|
||
s = find_pc_symtab (stop_pc);
|
||
if (s && s->language != language_asm)
|
||
ecs->stop_func_start = gdbarch_skip_prologue (current_gdbarch,
|
||
ecs->stop_func_start);
|
||
|
||
stop_func_sal = find_pc_line (stop_pc, 0);
|
||
|
||
/* OK, we're just going to keep stepping here. */
|
||
if (stop_func_sal.pc == stop_pc)
|
||
{
|
||
/* We're there already. Just stop stepping now. */
|
||
ecs->event_thread->stop_step = 1;
|
||
print_stop_reason (END_STEPPING_RANGE, 0);
|
||
stop_stepping (ecs);
|
||
}
|
||
else
|
||
{
|
||
/* Else just reset the step range and keep going.
|
||
No step-resume breakpoint, they don't work for
|
||
epilogues, which can have multiple entry paths. */
|
||
ecs->event_thread->step_range_start = stop_func_sal.pc;
|
||
ecs->event_thread->step_range_end = stop_func_sal.end;
|
||
keep_going (ecs);
|
||
}
|
||
return;
|
||
}
|
||
|
||
/* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
|
||
This is used to both functions and to skip over code. */
|
||
|
||
static void
|
||
insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal,
|
||
struct frame_id sr_id)
|
||
{
|
||
/* There should never be more than one step-resume or longjmp-resume
|
||
breakpoint per thread, so we should never be setting a new
|
||
step_resume_breakpoint when one is already active. */
|
||
gdb_assert (inferior_thread ()->step_resume_breakpoint == NULL);
|
||
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"infrun: inserting step-resume breakpoint at 0x%s\n",
|
||
paddr_nz (sr_sal.pc));
|
||
|
||
inferior_thread ()->step_resume_breakpoint
|
||
= set_momentary_breakpoint (sr_sal, sr_id, bp_step_resume);
|
||
}
|
||
|
||
/* Insert a "step-resume breakpoint" at RETURN_FRAME.pc. This is used
|
||
to skip a potential signal handler.
|
||
|
||
This is called with the interrupted function's frame. The signal
|
||
handler, when it returns, will resume the interrupted function at
|
||
RETURN_FRAME.pc. */
|
||
|
||
static void
|
||
insert_step_resume_breakpoint_at_frame (struct frame_info *return_frame)
|
||
{
|
||
struct symtab_and_line sr_sal;
|
||
|
||
gdb_assert (return_frame != NULL);
|
||
init_sal (&sr_sal); /* initialize to zeros */
|
||
|
||
sr_sal.pc = gdbarch_addr_bits_remove
|
||
(current_gdbarch, get_frame_pc (return_frame));
|
||
sr_sal.section = find_pc_overlay (sr_sal.pc);
|
||
|
||
insert_step_resume_breakpoint_at_sal (sr_sal, get_frame_id (return_frame));
|
||
}
|
||
|
||
/* Similar to insert_step_resume_breakpoint_at_frame, except
|
||
but a breakpoint at the previous frame's PC. This is used to
|
||
skip a function after stepping into it (for "next" or if the called
|
||
function has no debugging information).
|
||
|
||
The current function has almost always been reached by single
|
||
stepping a call or return instruction. NEXT_FRAME belongs to the
|
||
current function, and the breakpoint will be set at the caller's
|
||
resume address.
|
||
|
||
This is a separate function rather than reusing
|
||
insert_step_resume_breakpoint_at_frame in order to avoid
|
||
get_prev_frame, which may stop prematurely (see the implementation
|
||
of frame_unwind_id for an example). */
|
||
|
||
static void
|
||
insert_step_resume_breakpoint_at_caller (struct frame_info *next_frame)
|
||
{
|
||
struct symtab_and_line sr_sal;
|
||
|
||
/* We shouldn't have gotten here if we don't know where the call site
|
||
is. */
|
||
gdb_assert (frame_id_p (frame_unwind_id (next_frame)));
|
||
|
||
init_sal (&sr_sal); /* initialize to zeros */
|
||
|
||
sr_sal.pc = gdbarch_addr_bits_remove
|
||
(current_gdbarch, frame_pc_unwind (next_frame));
|
||
sr_sal.section = find_pc_overlay (sr_sal.pc);
|
||
|
||
insert_step_resume_breakpoint_at_sal (sr_sal, frame_unwind_id (next_frame));
|
||
}
|
||
|
||
/* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
|
||
new breakpoint at the target of a jmp_buf. The handling of
|
||
longjmp-resume uses the same mechanisms used for handling
|
||
"step-resume" breakpoints. */
|
||
|
||
static void
|
||
insert_longjmp_resume_breakpoint (CORE_ADDR pc)
|
||
{
|
||
/* There should never be more than one step-resume or longjmp-resume
|
||
breakpoint per thread, so we should never be setting a new
|
||
longjmp_resume_breakpoint when one is already active. */
|
||
gdb_assert (inferior_thread ()->step_resume_breakpoint == NULL);
|
||
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog,
|
||
"infrun: inserting longjmp-resume breakpoint at 0x%s\n",
|
||
paddr_nz (pc));
|
||
|
||
inferior_thread ()->step_resume_breakpoint =
|
||
set_momentary_breakpoint_at_pc (pc, bp_longjmp_resume);
|
||
}
|
||
|
||
static void
|
||
stop_stepping (struct execution_control_state *ecs)
|
||
{
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: stop_stepping\n");
|
||
|
||
/* Let callers know we don't want to wait for the inferior anymore. */
|
||
ecs->wait_some_more = 0;
|
||
}
|
||
|
||
/* This function handles various cases where we need to continue
|
||
waiting for the inferior. */
|
||
/* (Used to be the keep_going: label in the old wait_for_inferior) */
|
||
|
||
static void
|
||
keep_going (struct execution_control_state *ecs)
|
||
{
|
||
/* Save the pc before execution, to compare with pc after stop. */
|
||
ecs->event_thread->prev_pc = read_pc (); /* Might have been DECR_AFTER_BREAK */
|
||
|
||
/* If we did not do break;, it means we should keep running the
|
||
inferior and not return to debugger. */
|
||
|
||
if (ecs->event_thread->trap_expected
|
||
&& ecs->event_thread->stop_signal != TARGET_SIGNAL_TRAP)
|
||
{
|
||
/* We took a signal (which we are supposed to pass through to
|
||
the inferior, else we'd not get here) and we haven't yet
|
||
gotten our trap. Simply continue. */
|
||
resume (currently_stepping (ecs->event_thread),
|
||
ecs->event_thread->stop_signal);
|
||
}
|
||
else
|
||
{
|
||
/* Either the trap was not expected, but we are continuing
|
||
anyway (the user asked that this signal be passed to the
|
||
child)
|
||
-- or --
|
||
The signal was SIGTRAP, e.g. it was our signal, but we
|
||
decided we should resume from it.
|
||
|
||
We're going to run this baby now!
|
||
|
||
Note that insert_breakpoints won't try to re-insert
|
||
already inserted breakpoints. Therefore, we don't
|
||
care if breakpoints were already inserted, or not. */
|
||
|
||
if (ecs->event_thread->stepping_over_breakpoint)
|
||
{
|
||
if (! use_displaced_stepping (current_gdbarch))
|
||
/* Since we can't do a displaced step, we have to remove
|
||
the breakpoint while we step it. To keep things
|
||
simple, we remove them all. */
|
||
remove_breakpoints ();
|
||
}
|
||
else
|
||
{
|
||
struct gdb_exception e;
|
||
/* Stop stepping when inserting breakpoints
|
||
has failed. */
|
||
TRY_CATCH (e, RETURN_MASK_ERROR)
|
||
{
|
||
insert_breakpoints ();
|
||
}
|
||
if (e.reason < 0)
|
||
{
|
||
stop_stepping (ecs);
|
||
return;
|
||
}
|
||
}
|
||
|
||
ecs->event_thread->trap_expected = ecs->event_thread->stepping_over_breakpoint;
|
||
|
||
/* Do not deliver SIGNAL_TRAP (except when the user explicitly
|
||
specifies that such a signal should be delivered to the
|
||
target program).
|
||
|
||
Typically, this would occure when a user is debugging a
|
||
target monitor on a simulator: the target monitor sets a
|
||
breakpoint; the simulator encounters this break-point and
|
||
halts the simulation handing control to GDB; GDB, noteing
|
||
that the break-point isn't valid, returns control back to the
|
||
simulator; the simulator then delivers the hardware
|
||
equivalent of a SIGNAL_TRAP to the program being debugged. */
|
||
|
||
if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP
|
||
&& !signal_program[ecs->event_thread->stop_signal])
|
||
ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
|
||
|
||
resume (currently_stepping (ecs->event_thread),
|
||
ecs->event_thread->stop_signal);
|
||
}
|
||
|
||
prepare_to_wait (ecs);
|
||
}
|
||
|
||
/* This function normally comes after a resume, before
|
||
handle_inferior_event exits. It takes care of any last bits of
|
||
housekeeping, and sets the all-important wait_some_more flag. */
|
||
|
||
static void
|
||
prepare_to_wait (struct execution_control_state *ecs)
|
||
{
|
||
if (debug_infrun)
|
||
fprintf_unfiltered (gdb_stdlog, "infrun: prepare_to_wait\n");
|
||
if (infwait_state == infwait_normal_state)
|
||
{
|
||
overlay_cache_invalid = 1;
|
||
|
||
/* We have to invalidate the registers BEFORE calling
|
||
target_wait because they can be loaded from the target while
|
||
in target_wait. This makes remote debugging a bit more
|
||
efficient for those targets that provide critical registers
|
||
as part of their normal status mechanism. */
|
||
|
||
registers_changed ();
|
||
waiton_ptid = pid_to_ptid (-1);
|
||
}
|
||
/* This is the old end of the while loop. Let everybody know we
|
||
want to wait for the inferior some more and get called again
|
||
soon. */
|
||
ecs->wait_some_more = 1;
|
||
}
|
||
|
||
/* Print why the inferior has stopped. We always print something when
|
||
the inferior exits, or receives a signal. The rest of the cases are
|
||
dealt with later on in normal_stop() and print_it_typical(). Ideally
|
||
there should be a call to this function from handle_inferior_event()
|
||
each time stop_stepping() is called.*/
|
||
static void
|
||
print_stop_reason (enum inferior_stop_reason stop_reason, int stop_info)
|
||
{
|
||
switch (stop_reason)
|
||
{
|
||
case END_STEPPING_RANGE:
|
||
/* We are done with a step/next/si/ni command. */
|
||
/* For now print nothing. */
|
||
/* Print a message only if not in the middle of doing a "step n"
|
||
operation for n > 1 */
|
||
if (!inferior_thread ()->step_multi
|
||
|| !inferior_thread ()->stop_step)
|
||
if (ui_out_is_mi_like_p (uiout))
|
||
ui_out_field_string
|
||
(uiout, "reason",
|
||
async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE));
|
||
break;
|
||
case SIGNAL_EXITED:
|
||
/* The inferior was terminated by a signal. */
|
||
annotate_signalled ();
|
||
if (ui_out_is_mi_like_p (uiout))
|
||
ui_out_field_string
|
||
(uiout, "reason",
|
||
async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED));
|
||
ui_out_text (uiout, "\nProgram terminated with signal ");
|
||
annotate_signal_name ();
|
||
ui_out_field_string (uiout, "signal-name",
|
||
target_signal_to_name (stop_info));
|
||
annotate_signal_name_end ();
|
||
ui_out_text (uiout, ", ");
|
||
annotate_signal_string ();
|
||
ui_out_field_string (uiout, "signal-meaning",
|
||
target_signal_to_string (stop_info));
|
||
annotate_signal_string_end ();
|
||
ui_out_text (uiout, ".\n");
|
||
ui_out_text (uiout, "The program no longer exists.\n");
|
||
break;
|
||
case EXITED:
|
||
/* The inferior program is finished. */
|
||
annotate_exited (stop_info);
|
||
if (stop_info)
|
||
{
|
||
if (ui_out_is_mi_like_p (uiout))
|
||
ui_out_field_string (uiout, "reason",
|
||
async_reason_lookup (EXEC_ASYNC_EXITED));
|
||
ui_out_text (uiout, "\nProgram exited with code ");
|
||
ui_out_field_fmt (uiout, "exit-code", "0%o",
|
||
(unsigned int) stop_info);
|
||
ui_out_text (uiout, ".\n");
|
||
}
|
||
else
|
||
{
|
||
if (ui_out_is_mi_like_p (uiout))
|
||
ui_out_field_string
|
||
(uiout, "reason",
|
||
async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY));
|
||
ui_out_text (uiout, "\nProgram exited normally.\n");
|
||
}
|
||
/* Support the --return-child-result option. */
|
||
return_child_result_value = stop_info;
|
||
break;
|
||
case SIGNAL_RECEIVED:
|
||
/* Signal received. The signal table tells us to print about
|
||
it. */
|
||
annotate_signal ();
|
||
|
||
if (stop_info == TARGET_SIGNAL_0 && !ui_out_is_mi_like_p (uiout))
|
||
{
|
||
struct thread_info *t = inferior_thread ();
|
||
|
||
ui_out_text (uiout, "\n[");
|
||
ui_out_field_string (uiout, "thread-name",
|
||
target_pid_to_str (t->ptid));
|
||
ui_out_field_fmt (uiout, "thread-id", "] #%d", t->num);
|
||
ui_out_text (uiout, " stopped");
|
||
}
|
||
else
|
||
{
|
||
ui_out_text (uiout, "\nProgram received signal ");
|
||
annotate_signal_name ();
|
||
if (ui_out_is_mi_like_p (uiout))
|
||
ui_out_field_string
|
||
(uiout, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED));
|
||
ui_out_field_string (uiout, "signal-name",
|
||
target_signal_to_name (stop_info));
|
||
annotate_signal_name_end ();
|
||
ui_out_text (uiout, ", ");
|
||
annotate_signal_string ();
|
||
ui_out_field_string (uiout, "signal-meaning",
|
||
target_signal_to_string (stop_info));
|
||
annotate_signal_string_end ();
|
||
}
|
||
ui_out_text (uiout, ".\n");
|
||
break;
|
||
case NO_HISTORY:
|
||
/* Reverse execution: target ran out of history info. */
|
||
ui_out_text (uiout, "\nNo more reverse-execution history.\n");
|
||
break;
|
||
default:
|
||
internal_error (__FILE__, __LINE__,
|
||
_("print_stop_reason: unrecognized enum value"));
|
||
break;
|
||
}
|
||
}
|
||
|
||
|
||
/* Here to return control to GDB when the inferior stops for real.
|
||
Print appropriate messages, remove breakpoints, give terminal our modes.
|
||
|
||
STOP_PRINT_FRAME nonzero means print the executing frame
|
||
(pc, function, args, file, line number and line text).
|
||
BREAKPOINTS_FAILED nonzero means stop was due to error
|
||
attempting to insert breakpoints. */
|
||
|
||
void
|
||
normal_stop (void)
|
||
{
|
||
struct target_waitstatus last;
|
||
ptid_t last_ptid;
|
||
|
||
get_last_target_status (&last_ptid, &last);
|
||
|
||
/* In non-stop mode, we don't want GDB to switch threads behind the
|
||
user's back, to avoid races where the user is typing a command to
|
||
apply to thread x, but GDB switches to thread y before the user
|
||
finishes entering the command. */
|
||
|
||
/* As with the notification of thread events, we want to delay
|
||
notifying the user that we've switched thread context until
|
||
the inferior actually stops.
|
||
|
||
There's no point in saying anything if the inferior has exited.
|
||
Note that SIGNALLED here means "exited with a signal", not
|
||
"received a signal". */
|
||
if (!non_stop
|
||
&& !ptid_equal (previous_inferior_ptid, inferior_ptid)
|
||
&& target_has_execution
|
||
&& last.kind != TARGET_WAITKIND_SIGNALLED
|
||
&& last.kind != TARGET_WAITKIND_EXITED)
|
||
{
|
||
target_terminal_ours_for_output ();
|
||
printf_filtered (_("[Switching to %s]\n"),
|
||
target_pid_to_str (inferior_ptid));
|
||
annotate_thread_changed ();
|
||
previous_inferior_ptid = inferior_ptid;
|
||
}
|
||
|
||
/* NOTE drow/2004-01-17: Is this still necessary? */
|
||
/* Make sure that the current_frame's pc is correct. This
|
||
is a correction for setting up the frame info before doing
|
||
gdbarch_decr_pc_after_break */
|
||
if (target_has_execution)
|
||
/* FIXME: cagney/2002-12-06: Has the PC changed? Thanks to
|
||
gdbarch_decr_pc_after_break, the program counter can change. Ask the
|
||
frame code to check for this and sort out any resultant mess.
|
||
gdbarch_decr_pc_after_break needs to just go away. */
|
||
deprecated_update_frame_pc_hack (get_current_frame (), read_pc ());
|
||
|
||
if (!breakpoints_always_inserted_mode () && target_has_execution)
|
||
{
|
||
if (remove_breakpoints ())
|
||
{
|
||
target_terminal_ours_for_output ();
|
||
printf_filtered (_("\
|
||
Cannot remove breakpoints because program is no longer writable.\n\
|
||
It might be running in another process.\n\
|
||
Further execution is probably impossible.\n"));
|
||
}
|
||
}
|
||
|
||
/* If an auto-display called a function and that got a signal,
|
||
delete that auto-display to avoid an infinite recursion. */
|
||
|
||
if (stopped_by_random_signal)
|
||
disable_current_display ();
|
||
|
||
/* Don't print a message if in the middle of doing a "step n"
|
||
operation for n > 1 */
|
||
if (target_has_execution
|
||
&& last.kind != TARGET_WAITKIND_SIGNALLED
|
||
&& last.kind != TARGET_WAITKIND_EXITED
|
||
&& inferior_thread ()->step_multi
|
||
&& inferior_thread ()->stop_step)
|
||
goto done;
|
||
|
||
target_terminal_ours ();
|
||
|
||
/* Set the current source location. This will also happen if we
|
||
display the frame below, but the current SAL will be incorrect
|
||
during a user hook-stop function. */
|
||
if (target_has_stack && !stop_stack_dummy)
|
||
set_current_sal_from_frame (get_current_frame (), 1);
|
||
|
||
if (!target_has_stack)
|
||
goto done;
|
||
|
||
if (last.kind == TARGET_WAITKIND_SIGNALLED
|
||
|| last.kind == TARGET_WAITKIND_EXITED)
|
||
goto done;
|
||
|
||
/* Select innermost stack frame - i.e., current frame is frame 0,
|
||
and current location is based on that.
|
||
Don't do this on return from a stack dummy routine,
|
||
or if the program has exited. */
|
||
|
||
if (!stop_stack_dummy)
|
||
{
|
||
select_frame (get_current_frame ());
|
||
|
||
/* Print current location without a level number, if
|
||
we have changed functions or hit a breakpoint.
|
||
Print source line if we have one.
|
||
bpstat_print() contains the logic deciding in detail
|
||
what to print, based on the event(s) that just occurred. */
|
||
|
||
/* If --batch-silent is enabled then there's no need to print the current
|
||
source location, and to try risks causing an error message about
|
||
missing source files. */
|
||
if (stop_print_frame && !batch_silent)
|
||
{
|
||
int bpstat_ret;
|
||
int source_flag;
|
||
int do_frame_printing = 1;
|
||
struct thread_info *tp = inferior_thread ();
|
||
|
||
bpstat_ret = bpstat_print (tp->stop_bpstat);
|
||
switch (bpstat_ret)
|
||
{
|
||
case PRINT_UNKNOWN:
|
||
/* If we had hit a shared library event breakpoint,
|
||
bpstat_print would print out this message. If we hit
|
||
an OS-level shared library event, do the same
|
||
thing. */
|
||
if (last.kind == TARGET_WAITKIND_LOADED)
|
||
{
|
||
printf_filtered (_("Stopped due to shared library event\n"));
|
||
source_flag = SRC_LINE; /* something bogus */
|
||
do_frame_printing = 0;
|
||
break;
|
||
}
|
||
|
||
/* FIXME: cagney/2002-12-01: Given that a frame ID does
|
||
(or should) carry around the function and does (or
|
||
should) use that when doing a frame comparison. */
|
||
if (tp->stop_step
|
||
&& frame_id_eq (tp->step_frame_id,
|
||
get_frame_id (get_current_frame ()))
|
||
&& step_start_function == find_pc_function (stop_pc))
|
||
source_flag = SRC_LINE; /* finished step, just print source line */
|
||
else
|
||
source_flag = SRC_AND_LOC; /* print location and source line */
|
||
break;
|
||
case PRINT_SRC_AND_LOC:
|
||
source_flag = SRC_AND_LOC; /* print location and source line */
|
||
break;
|
||
case PRINT_SRC_ONLY:
|
||
source_flag = SRC_LINE;
|
||
break;
|
||
case PRINT_NOTHING:
|
||
source_flag = SRC_LINE; /* something bogus */
|
||
do_frame_printing = 0;
|
||
break;
|
||
default:
|
||
internal_error (__FILE__, __LINE__, _("Unknown value."));
|
||
}
|
||
|
||
if (ui_out_is_mi_like_p (uiout))
|
||
{
|
||
|
||
ui_out_field_int (uiout, "thread-id",
|
||
pid_to_thread_id (inferior_ptid));
|
||
if (non_stop)
|
||
{
|
||
struct cleanup *back_to = make_cleanup_ui_out_list_begin_end
|
||
(uiout, "stopped-threads");
|
||
ui_out_field_int (uiout, NULL,
|
||
pid_to_thread_id (inferior_ptid));
|
||
do_cleanups (back_to);
|
||
}
|
||
else
|
||
ui_out_field_string (uiout, "stopped-threads", "all");
|
||
}
|
||
/* The behavior of this routine with respect to the source
|
||
flag is:
|
||
SRC_LINE: Print only source line
|
||
LOCATION: Print only location
|
||
SRC_AND_LOC: Print location and source line */
|
||
if (do_frame_printing)
|
||
print_stack_frame (get_selected_frame (NULL), 0, source_flag);
|
||
|
||
/* Display the auto-display expressions. */
|
||
do_displays ();
|
||
}
|
||
}
|
||
|
||
/* Save the function value return registers, if we care.
|
||
We might be about to restore their previous contents. */
|
||
if (inferior_thread ()->proceed_to_finish)
|
||
{
|
||
/* This should not be necessary. */
|
||
if (stop_registers)
|
||
regcache_xfree (stop_registers);
|
||
|
||
/* NB: The copy goes through to the target picking up the value of
|
||
all the registers. */
|
||
stop_registers = regcache_dup (get_current_regcache ());
|
||
}
|
||
|
||
if (stop_stack_dummy)
|
||
{
|
||
/* Pop the empty frame that contains the stack dummy. POP_FRAME
|
||
ends with a setting of the current frame, so we can use that
|
||
next. */
|
||
frame_pop (get_current_frame ());
|
||
/* Set stop_pc to what it was before we called the function.
|
||
Can't rely on restore_inferior_status because that only gets
|
||
called if we don't stop in the called function. */
|
||
stop_pc = read_pc ();
|
||
select_frame (get_current_frame ());
|
||
}
|
||
|
||
done:
|
||
annotate_stopped ();
|
||
if (!suppress_stop_observer
|
||
&& !(target_has_execution
|
||
&& last.kind != TARGET_WAITKIND_SIGNALLED
|
||
&& last.kind != TARGET_WAITKIND_EXITED
|
||
&& inferior_thread ()->step_multi))
|
||
{
|
||
if (!ptid_equal (inferior_ptid, null_ptid))
|
||
observer_notify_normal_stop (inferior_thread ()->stop_bpstat);
|
||
else
|
||
observer_notify_normal_stop (NULL);
|
||
}
|
||
if (target_has_execution
|
||
&& last.kind != TARGET_WAITKIND_SIGNALLED
|
||
&& last.kind != TARGET_WAITKIND_EXITED)
|
||
{
|
||
/* Delete the breakpoint we stopped at, if it wants to be deleted.
|
||
Delete any breakpoint that is to be deleted at the next stop. */
|
||
breakpoint_auto_delete (inferior_thread ()->stop_bpstat);
|
||
|
||
if (!non_stop)
|
||
set_running (pid_to_ptid (-1), 0);
|
||
else
|
||
set_running (inferior_ptid, 0);
|
||
}
|
||
|
||
/* Look up the hook_stop and run it (CLI internally handles problem
|
||
of stop_command's pre-hook not existing). */
|
||
if (stop_command)
|
||
catch_errors (hook_stop_stub, stop_command,
|
||
"Error while running hook_stop:\n", RETURN_MASK_ALL);
|
||
|
||
}
|
||
|
||
static int
|
||
hook_stop_stub (void *cmd)
|
||
{
|
||
execute_cmd_pre_hook ((struct cmd_list_element *) cmd);
|
||
return (0);
|
||
}
|
||
|
||
int
|
||
signal_stop_state (int signo)
|
||
{
|
||
return signal_stop[signo];
|
||
}
|
||
|
||
int
|
||
signal_print_state (int signo)
|
||
{
|
||
return signal_print[signo];
|
||
}
|
||
|
||
int
|
||
signal_pass_state (int signo)
|
||
{
|
||
return signal_program[signo];
|
||
}
|
||
|
||
int
|
||
signal_stop_update (int signo, int state)
|
||
{
|
||
int ret = signal_stop[signo];
|
||
signal_stop[signo] = state;
|
||
return ret;
|
||
}
|
||
|
||
int
|
||
signal_print_update (int signo, int state)
|
||
{
|
||
int ret = signal_print[signo];
|
||
signal_print[signo] = state;
|
||
return ret;
|
||
}
|
||
|
||
int
|
||
signal_pass_update (int signo, int state)
|
||
{
|
||
int ret = signal_program[signo];
|
||
signal_program[signo] = state;
|
||
return ret;
|
||
}
|
||
|
||
static void
|
||
sig_print_header (void)
|
||
{
|
||
printf_filtered (_("\
|
||
Signal Stop\tPrint\tPass to program\tDescription\n"));
|
||
}
|
||
|
||
static void
|
||
sig_print_info (enum target_signal oursig)
|
||
{
|
||
char *name = target_signal_to_name (oursig);
|
||
int name_padding = 13 - strlen (name);
|
||
|
||
if (name_padding <= 0)
|
||
name_padding = 0;
|
||
|
||
printf_filtered ("%s", name);
|
||
printf_filtered ("%*.*s ", name_padding, name_padding, " ");
|
||
printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No");
|
||
printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No");
|
||
printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No");
|
||
printf_filtered ("%s\n", target_signal_to_string (oursig));
|
||
}
|
||
|
||
/* Specify how various signals in the inferior should be handled. */
|
||
|
||
static void
|
||
handle_command (char *args, int from_tty)
|
||
{
|
||
char **argv;
|
||
int digits, wordlen;
|
||
int sigfirst, signum, siglast;
|
||
enum target_signal oursig;
|
||
int allsigs;
|
||
int nsigs;
|
||
unsigned char *sigs;
|
||
struct cleanup *old_chain;
|
||
|
||
if (args == NULL)
|
||
{
|
||
error_no_arg (_("signal to handle"));
|
||
}
|
||
|
||
/* Allocate and zero an array of flags for which signals to handle. */
|
||
|
||
nsigs = (int) TARGET_SIGNAL_LAST;
|
||
sigs = (unsigned char *) alloca (nsigs);
|
||
memset (sigs, 0, nsigs);
|
||
|
||
/* Break the command line up into args. */
|
||
|
||
argv = gdb_buildargv (args);
|
||
old_chain = make_cleanup_freeargv (argv);
|
||
|
||
/* Walk through the args, looking for signal oursigs, signal names, and
|
||
actions. Signal numbers and signal names may be interspersed with
|
||
actions, with the actions being performed for all signals cumulatively
|
||
specified. Signal ranges can be specified as <LOW>-<HIGH>. */
|
||
|
||
while (*argv != NULL)
|
||
{
|
||
wordlen = strlen (*argv);
|
||
for (digits = 0; isdigit ((*argv)[digits]); digits++)
|
||
{;
|
||
}
|
||
allsigs = 0;
|
||
sigfirst = siglast = -1;
|
||
|
||
if (wordlen >= 1 && !strncmp (*argv, "all", wordlen))
|
||
{
|
||
/* Apply action to all signals except those used by the
|
||
debugger. Silently skip those. */
|
||
allsigs = 1;
|
||
sigfirst = 0;
|
||
siglast = nsigs - 1;
|
||
}
|
||
else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen))
|
||
{
|
||
SET_SIGS (nsigs, sigs, signal_stop);
|
||
SET_SIGS (nsigs, sigs, signal_print);
|
||
}
|
||
else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen))
|
||
{
|
||
UNSET_SIGS (nsigs, sigs, signal_program);
|
||
}
|
||
else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen))
|
||
{
|
||
SET_SIGS (nsigs, sigs, signal_print);
|
||
}
|
||
else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen))
|
||
{
|
||
SET_SIGS (nsigs, sigs, signal_program);
|
||
}
|
||
else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen))
|
||
{
|
||
UNSET_SIGS (nsigs, sigs, signal_stop);
|
||
}
|
||
else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen))
|
||
{
|
||
SET_SIGS (nsigs, sigs, signal_program);
|
||
}
|
||
else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen))
|
||
{
|
||
UNSET_SIGS (nsigs, sigs, signal_print);
|
||
UNSET_SIGS (nsigs, sigs, signal_stop);
|
||
}
|
||
else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen))
|
||
{
|
||
UNSET_SIGS (nsigs, sigs, signal_program);
|
||
}
|
||
else if (digits > 0)
|
||
{
|
||
/* It is numeric. The numeric signal refers to our own
|
||
internal signal numbering from target.h, not to host/target
|
||
signal number. This is a feature; users really should be
|
||
using symbolic names anyway, and the common ones like
|
||
SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
|
||
|
||
sigfirst = siglast = (int)
|
||
target_signal_from_command (atoi (*argv));
|
||
if ((*argv)[digits] == '-')
|
||
{
|
||
siglast = (int)
|
||
target_signal_from_command (atoi ((*argv) + digits + 1));
|
||
}
|
||
if (sigfirst > siglast)
|
||
{
|
||
/* Bet he didn't figure we'd think of this case... */
|
||
signum = sigfirst;
|
||
sigfirst = siglast;
|
||
siglast = signum;
|
||
}
|
||
}
|
||
else
|
||
{
|
||
oursig = target_signal_from_name (*argv);
|
||
if (oursig != TARGET_SIGNAL_UNKNOWN)
|
||
{
|
||
sigfirst = siglast = (int) oursig;
|
||
}
|
||
else
|
||
{
|
||
/* Not a number and not a recognized flag word => complain. */
|
||
error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv);
|
||
}
|
||
}
|
||
|
||
/* If any signal numbers or symbol names were found, set flags for
|
||
which signals to apply actions to. */
|
||
|
||
for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++)
|
||
{
|
||
switch ((enum target_signal) signum)
|
||
{
|
||
case TARGET_SIGNAL_TRAP:
|
||
case TARGET_SIGNAL_INT:
|
||
if (!allsigs && !sigs[signum])
|
||
{
|
||
if (query ("%s is used by the debugger.\n\
|
||
Are you sure you want to change it? ", target_signal_to_name ((enum target_signal) signum)))
|
||
{
|
||
sigs[signum] = 1;
|
||
}
|
||
else
|
||
{
|
||
printf_unfiltered (_("Not confirmed, unchanged.\n"));
|
||
gdb_flush (gdb_stdout);
|
||
}
|
||
}
|
||
break;
|
||
case TARGET_SIGNAL_0:
|
||
case TARGET_SIGNAL_DEFAULT:
|
||
case TARGET_SIGNAL_UNKNOWN:
|
||
/* Make sure that "all" doesn't print these. */
|
||
break;
|
||
default:
|
||
sigs[signum] = 1;
|
||
break;
|
||
}
|
||
}
|
||
|
||
argv++;
|
||
}
|
||
|
||
target_notice_signals (inferior_ptid);
|
||
|
||
if (from_tty)
|
||
{
|
||
/* Show the results. */
|
||
sig_print_header ();
|
||
for (signum = 0; signum < nsigs; signum++)
|
||
{
|
||
if (sigs[signum])
|
||
{
|
||
sig_print_info (signum);
|
||
}
|
||
}
|
||
}
|
||
|
||
do_cleanups (old_chain);
|
||
}
|
||
|
||
static void
|
||
xdb_handle_command (char *args, int from_tty)
|
||
{
|
||
char **argv;
|
||
struct cleanup *old_chain;
|
||
|
||
if (args == NULL)
|
||
error_no_arg (_("xdb command"));
|
||
|
||
/* Break the command line up into args. */
|
||
|
||
argv = gdb_buildargv (args);
|
||
old_chain = make_cleanup_freeargv (argv);
|
||
if (argv[1] != (char *) NULL)
|
||
{
|
||
char *argBuf;
|
||
int bufLen;
|
||
|
||
bufLen = strlen (argv[0]) + 20;
|
||
argBuf = (char *) xmalloc (bufLen);
|
||
if (argBuf)
|
||
{
|
||
int validFlag = 1;
|
||
enum target_signal oursig;
|
||
|
||
oursig = target_signal_from_name (argv[0]);
|
||
memset (argBuf, 0, bufLen);
|
||
if (strcmp (argv[1], "Q") == 0)
|
||
sprintf (argBuf, "%s %s", argv[0], "noprint");
|
||
else
|
||
{
|
||
if (strcmp (argv[1], "s") == 0)
|
||
{
|
||
if (!signal_stop[oursig])
|
||
sprintf (argBuf, "%s %s", argv[0], "stop");
|
||
else
|
||
sprintf (argBuf, "%s %s", argv[0], "nostop");
|
||
}
|
||
else if (strcmp (argv[1], "i") == 0)
|
||
{
|
||
if (!signal_program[oursig])
|
||
sprintf (argBuf, "%s %s", argv[0], "pass");
|
||
else
|
||
sprintf (argBuf, "%s %s", argv[0], "nopass");
|
||
}
|
||
else if (strcmp (argv[1], "r") == 0)
|
||
{
|
||
if (!signal_print[oursig])
|
||
sprintf (argBuf, "%s %s", argv[0], "print");
|
||
else
|
||
sprintf (argBuf, "%s %s", argv[0], "noprint");
|
||
}
|
||
else
|
||
validFlag = 0;
|
||
}
|
||
if (validFlag)
|
||
handle_command (argBuf, from_tty);
|
||
else
|
||
printf_filtered (_("Invalid signal handling flag.\n"));
|
||
if (argBuf)
|
||
xfree (argBuf);
|
||
}
|
||
}
|
||
do_cleanups (old_chain);
|
||
}
|
||
|
||
/* Print current contents of the tables set by the handle command.
|
||
It is possible we should just be printing signals actually used
|
||
by the current target (but for things to work right when switching
|
||
targets, all signals should be in the signal tables). */
|
||
|
||
static void
|
||
signals_info (char *signum_exp, int from_tty)
|
||
{
|
||
enum target_signal oursig;
|
||
sig_print_header ();
|
||
|
||
if (signum_exp)
|
||
{
|
||
/* First see if this is a symbol name. */
|
||
oursig = target_signal_from_name (signum_exp);
|
||
if (oursig == TARGET_SIGNAL_UNKNOWN)
|
||
{
|
||
/* No, try numeric. */
|
||
oursig =
|
||
target_signal_from_command (parse_and_eval_long (signum_exp));
|
||
}
|
||
sig_print_info (oursig);
|
||
return;
|
||
}
|
||
|
||
printf_filtered ("\n");
|
||
/* These ugly casts brought to you by the native VAX compiler. */
|
||
for (oursig = TARGET_SIGNAL_FIRST;
|
||
(int) oursig < (int) TARGET_SIGNAL_LAST;
|
||
oursig = (enum target_signal) ((int) oursig + 1))
|
||
{
|
||
QUIT;
|
||
|
||
if (oursig != TARGET_SIGNAL_UNKNOWN
|
||
&& oursig != TARGET_SIGNAL_DEFAULT && oursig != TARGET_SIGNAL_0)
|
||
sig_print_info (oursig);
|
||
}
|
||
|
||
printf_filtered (_("\nUse the \"handle\" command to change these tables.\n"));
|
||
}
|
||
|
||
struct inferior_status
|
||
{
|
||
enum target_signal stop_signal;
|
||
CORE_ADDR stop_pc;
|
||
bpstat stop_bpstat;
|
||
int stop_step;
|
||
int stop_stack_dummy;
|
||
int stopped_by_random_signal;
|
||
int stepping_over_breakpoint;
|
||
CORE_ADDR step_range_start;
|
||
CORE_ADDR step_range_end;
|
||
struct frame_id step_frame_id;
|
||
enum step_over_calls_kind step_over_calls;
|
||
CORE_ADDR step_resume_break_address;
|
||
int stop_after_trap;
|
||
int stop_soon;
|
||
|
||
/* These are here because if call_function_by_hand has written some
|
||
registers and then decides to call error(), we better not have changed
|
||
any registers. */
|
||
struct regcache *registers;
|
||
|
||
/* A frame unique identifier. */
|
||
struct frame_id selected_frame_id;
|
||
|
||
int breakpoint_proceeded;
|
||
int restore_stack_info;
|
||
int proceed_to_finish;
|
||
};
|
||
|
||
void
|
||
write_inferior_status_register (struct inferior_status *inf_status, int regno,
|
||
LONGEST val)
|
||
{
|
||
int size = register_size (current_gdbarch, regno);
|
||
void *buf = alloca (size);
|
||
store_signed_integer (buf, size, val);
|
||
regcache_raw_write (inf_status->registers, regno, buf);
|
||
}
|
||
|
||
/* Save all of the information associated with the inferior<==>gdb
|
||
connection. INF_STATUS is a pointer to a "struct inferior_status"
|
||
(defined in inferior.h). */
|
||
|
||
struct inferior_status *
|
||
save_inferior_status (int restore_stack_info)
|
||
{
|
||
struct inferior_status *inf_status = XMALLOC (struct inferior_status);
|
||
struct thread_info *tp = inferior_thread ();
|
||
struct inferior *inf = current_inferior ();
|
||
|
||
inf_status->stop_signal = tp->stop_signal;
|
||
inf_status->stop_pc = stop_pc;
|
||
inf_status->stop_step = tp->stop_step;
|
||
inf_status->stop_stack_dummy = stop_stack_dummy;
|
||
inf_status->stopped_by_random_signal = stopped_by_random_signal;
|
||
inf_status->stepping_over_breakpoint = tp->trap_expected;
|
||
inf_status->step_range_start = tp->step_range_start;
|
||
inf_status->step_range_end = tp->step_range_end;
|
||
inf_status->step_frame_id = tp->step_frame_id;
|
||
inf_status->step_over_calls = tp->step_over_calls;
|
||
inf_status->stop_after_trap = stop_after_trap;
|
||
inf_status->stop_soon = inf->stop_soon;
|
||
/* Save original bpstat chain here; replace it with copy of chain.
|
||
If caller's caller is walking the chain, they'll be happier if we
|
||
hand them back the original chain when restore_inferior_status is
|
||
called. */
|
||
inf_status->stop_bpstat = tp->stop_bpstat;
|
||
tp->stop_bpstat = bpstat_copy (tp->stop_bpstat);
|
||
inf_status->breakpoint_proceeded = breakpoint_proceeded;
|
||
inf_status->restore_stack_info = restore_stack_info;
|
||
inf_status->proceed_to_finish = tp->proceed_to_finish;
|
||
|
||
inf_status->registers = regcache_dup (get_current_regcache ());
|
||
|
||
inf_status->selected_frame_id = get_frame_id (get_selected_frame (NULL));
|
||
return inf_status;
|
||
}
|
||
|
||
static int
|
||
restore_selected_frame (void *args)
|
||
{
|
||
struct frame_id *fid = (struct frame_id *) args;
|
||
struct frame_info *frame;
|
||
|
||
frame = frame_find_by_id (*fid);
|
||
|
||
/* If inf_status->selected_frame_id is NULL, there was no previously
|
||
selected frame. */
|
||
if (frame == NULL)
|
||
{
|
||
warning (_("Unable to restore previously selected frame."));
|
||
return 0;
|
||
}
|
||
|
||
select_frame (frame);
|
||
|
||
return (1);
|
||
}
|
||
|
||
void
|
||
restore_inferior_status (struct inferior_status *inf_status)
|
||
{
|
||
struct thread_info *tp = inferior_thread ();
|
||
struct inferior *inf = current_inferior ();
|
||
|
||
tp->stop_signal = inf_status->stop_signal;
|
||
stop_pc = inf_status->stop_pc;
|
||
tp->stop_step = inf_status->stop_step;
|
||
stop_stack_dummy = inf_status->stop_stack_dummy;
|
||
stopped_by_random_signal = inf_status->stopped_by_random_signal;
|
||
tp->trap_expected = inf_status->stepping_over_breakpoint;
|
||
tp->step_range_start = inf_status->step_range_start;
|
||
tp->step_range_end = inf_status->step_range_end;
|
||
tp->step_frame_id = inf_status->step_frame_id;
|
||
tp->step_over_calls = inf_status->step_over_calls;
|
||
stop_after_trap = inf_status->stop_after_trap;
|
||
inf->stop_soon = inf_status->stop_soon;
|
||
bpstat_clear (&tp->stop_bpstat);
|
||
tp->stop_bpstat = inf_status->stop_bpstat;
|
||
breakpoint_proceeded = inf_status->breakpoint_proceeded;
|
||
tp->proceed_to_finish = inf_status->proceed_to_finish;
|
||
|
||
/* The inferior can be gone if the user types "print exit(0)"
|
||
(and perhaps other times). */
|
||
if (target_has_execution)
|
||
/* NB: The register write goes through to the target. */
|
||
regcache_cpy (get_current_regcache (), inf_status->registers);
|
||
regcache_xfree (inf_status->registers);
|
||
|
||
/* FIXME: If we are being called after stopping in a function which
|
||
is called from gdb, we should not be trying to restore the
|
||
selected frame; it just prints a spurious error message (The
|
||
message is useful, however, in detecting bugs in gdb (like if gdb
|
||
clobbers the stack)). In fact, should we be restoring the
|
||
inferior status at all in that case? . */
|
||
|
||
if (target_has_stack && inf_status->restore_stack_info)
|
||
{
|
||
/* The point of catch_errors is that if the stack is clobbered,
|
||
walking the stack might encounter a garbage pointer and
|
||
error() trying to dereference it. */
|
||
if (catch_errors
|
||
(restore_selected_frame, &inf_status->selected_frame_id,
|
||
"Unable to restore previously selected frame:\n",
|
||
RETURN_MASK_ERROR) == 0)
|
||
/* Error in restoring the selected frame. Select the innermost
|
||
frame. */
|
||
select_frame (get_current_frame ());
|
||
|
||
}
|
||
|
||
xfree (inf_status);
|
||
}
|
||
|
||
static void
|
||
do_restore_inferior_status_cleanup (void *sts)
|
||
{
|
||
restore_inferior_status (sts);
|
||
}
|
||
|
||
struct cleanup *
|
||
make_cleanup_restore_inferior_status (struct inferior_status *inf_status)
|
||
{
|
||
return make_cleanup (do_restore_inferior_status_cleanup, inf_status);
|
||
}
|
||
|
||
void
|
||
discard_inferior_status (struct inferior_status *inf_status)
|
||
{
|
||
/* See save_inferior_status for info on stop_bpstat. */
|
||
bpstat_clear (&inf_status->stop_bpstat);
|
||
regcache_xfree (inf_status->registers);
|
||
xfree (inf_status);
|
||
}
|
||
|
||
int
|
||
inferior_has_forked (ptid_t pid, ptid_t *child_pid)
|
||
{
|
||
struct target_waitstatus last;
|
||
ptid_t last_ptid;
|
||
|
||
get_last_target_status (&last_ptid, &last);
|
||
|
||
if (last.kind != TARGET_WAITKIND_FORKED)
|
||
return 0;
|
||
|
||
if (!ptid_equal (last_ptid, pid))
|
||
return 0;
|
||
|
||
*child_pid = last.value.related_pid;
|
||
return 1;
|
||
}
|
||
|
||
int
|
||
inferior_has_vforked (ptid_t pid, ptid_t *child_pid)
|
||
{
|
||
struct target_waitstatus last;
|
||
ptid_t last_ptid;
|
||
|
||
get_last_target_status (&last_ptid, &last);
|
||
|
||
if (last.kind != TARGET_WAITKIND_VFORKED)
|
||
return 0;
|
||
|
||
if (!ptid_equal (last_ptid, pid))
|
||
return 0;
|
||
|
||
*child_pid = last.value.related_pid;
|
||
return 1;
|
||
}
|
||
|
||
int
|
||
inferior_has_execd (ptid_t pid, char **execd_pathname)
|
||
{
|
||
struct target_waitstatus last;
|
||
ptid_t last_ptid;
|
||
|
||
get_last_target_status (&last_ptid, &last);
|
||
|
||
if (last.kind != TARGET_WAITKIND_EXECD)
|
||
return 0;
|
||
|
||
if (!ptid_equal (last_ptid, pid))
|
||
return 0;
|
||
|
||
*execd_pathname = xstrdup (last.value.execd_pathname);
|
||
return 1;
|
||
}
|
||
|
||
/* Oft used ptids */
|
||
ptid_t null_ptid;
|
||
ptid_t minus_one_ptid;
|
||
|
||
/* Create a ptid given the necessary PID, LWP, and TID components. */
|
||
|
||
ptid_t
|
||
ptid_build (int pid, long lwp, long tid)
|
||
{
|
||
ptid_t ptid;
|
||
|
||
ptid.pid = pid;
|
||
ptid.lwp = lwp;
|
||
ptid.tid = tid;
|
||
return ptid;
|
||
}
|
||
|
||
/* Create a ptid from just a pid. */
|
||
|
||
ptid_t
|
||
pid_to_ptid (int pid)
|
||
{
|
||
return ptid_build (pid, 0, 0);
|
||
}
|
||
|
||
/* Fetch the pid (process id) component from a ptid. */
|
||
|
||
int
|
||
ptid_get_pid (ptid_t ptid)
|
||
{
|
||
return ptid.pid;
|
||
}
|
||
|
||
/* Fetch the lwp (lightweight process) component from a ptid. */
|
||
|
||
long
|
||
ptid_get_lwp (ptid_t ptid)
|
||
{
|
||
return ptid.lwp;
|
||
}
|
||
|
||
/* Fetch the tid (thread id) component from a ptid. */
|
||
|
||
long
|
||
ptid_get_tid (ptid_t ptid)
|
||
{
|
||
return ptid.tid;
|
||
}
|
||
|
||
/* ptid_equal() is used to test equality of two ptids. */
|
||
|
||
int
|
||
ptid_equal (ptid_t ptid1, ptid_t ptid2)
|
||
{
|
||
return (ptid1.pid == ptid2.pid && ptid1.lwp == ptid2.lwp
|
||
&& ptid1.tid == ptid2.tid);
|
||
}
|
||
|
||
/* Returns true if PTID represents a process. */
|
||
|
||
int
|
||
ptid_is_pid (ptid_t ptid)
|
||
{
|
||
if (ptid_equal (minus_one_ptid, ptid))
|
||
return 0;
|
||
if (ptid_equal (null_ptid, ptid))
|
||
return 0;
|
||
|
||
return (ptid_get_lwp (ptid) == 0 && ptid_get_tid (ptid) == 0);
|
||
}
|
||
|
||
/* restore_inferior_ptid() will be used by the cleanup machinery
|
||
to restore the inferior_ptid value saved in a call to
|
||
save_inferior_ptid(). */
|
||
|
||
static void
|
||
restore_inferior_ptid (void *arg)
|
||
{
|
||
ptid_t *saved_ptid_ptr = arg;
|
||
inferior_ptid = *saved_ptid_ptr;
|
||
xfree (arg);
|
||
}
|
||
|
||
/* Save the value of inferior_ptid so that it may be restored by a
|
||
later call to do_cleanups(). Returns the struct cleanup pointer
|
||
needed for later doing the cleanup. */
|
||
|
||
struct cleanup *
|
||
save_inferior_ptid (void)
|
||
{
|
||
ptid_t *saved_ptid_ptr;
|
||
|
||
saved_ptid_ptr = xmalloc (sizeof (ptid_t));
|
||
*saved_ptid_ptr = inferior_ptid;
|
||
return make_cleanup (restore_inferior_ptid, saved_ptid_ptr);
|
||
}
|
||
|
||
|
||
/* User interface for reverse debugging:
|
||
Set exec-direction / show exec-direction commands
|
||
(returns error unless target implements to_set_exec_direction method). */
|
||
|
||
enum exec_direction_kind execution_direction = EXEC_FORWARD;
|
||
static const char exec_forward[] = "forward";
|
||
static const char exec_reverse[] = "reverse";
|
||
static const char *exec_direction = exec_forward;
|
||
static const char *exec_direction_names[] = {
|
||
exec_forward,
|
||
exec_reverse,
|
||
NULL
|
||
};
|
||
|
||
static void
|
||
set_exec_direction_func (char *args, int from_tty,
|
||
struct cmd_list_element *cmd)
|
||
{
|
||
if (target_can_execute_reverse)
|
||
{
|
||
if (!strcmp (exec_direction, exec_forward))
|
||
execution_direction = EXEC_FORWARD;
|
||
else if (!strcmp (exec_direction, exec_reverse))
|
||
execution_direction = EXEC_REVERSE;
|
||
}
|
||
}
|
||
|
||
static void
|
||
show_exec_direction_func (struct ui_file *out, int from_tty,
|
||
struct cmd_list_element *cmd, const char *value)
|
||
{
|
||
switch (execution_direction) {
|
||
case EXEC_FORWARD:
|
||
fprintf_filtered (out, _("Forward.\n"));
|
||
break;
|
||
case EXEC_REVERSE:
|
||
fprintf_filtered (out, _("Reverse.\n"));
|
||
break;
|
||
case EXEC_ERROR:
|
||
default:
|
||
fprintf_filtered (out,
|
||
_("Forward (target `%s' does not support exec-direction).\n"),
|
||
target_shortname);
|
||
break;
|
||
}
|
||
}
|
||
|
||
/* User interface for non-stop mode. */
|
||
|
||
int non_stop = 0;
|
||
static int non_stop_1 = 0;
|
||
|
||
static void
|
||
set_non_stop (char *args, int from_tty,
|
||
struct cmd_list_element *c)
|
||
{
|
||
if (target_has_execution)
|
||
{
|
||
non_stop_1 = non_stop;
|
||
error (_("Cannot change this setting while the inferior is running."));
|
||
}
|
||
|
||
non_stop = non_stop_1;
|
||
}
|
||
|
||
static void
|
||
show_non_stop (struct ui_file *file, int from_tty,
|
||
struct cmd_list_element *c, const char *value)
|
||
{
|
||
fprintf_filtered (file,
|
||
_("Controlling the inferior in non-stop mode is %s.\n"),
|
||
value);
|
||
}
|
||
|
||
|
||
void
|
||
_initialize_infrun (void)
|
||
{
|
||
int i;
|
||
int numsigs;
|
||
struct cmd_list_element *c;
|
||
|
||
add_info ("signals", signals_info, _("\
|
||
What debugger does when program gets various signals.\n\
|
||
Specify a signal as argument to print info on that signal only."));
|
||
add_info_alias ("handle", "signals", 0);
|
||
|
||
add_com ("handle", class_run, handle_command, _("\
|
||
Specify how to handle a signal.\n\
|
||
Args are signals and actions to apply to those signals.\n\
|
||
Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
|
||
from 1-15 are allowed for compatibility with old versions of GDB.\n\
|
||
Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
|
||
The special arg \"all\" is recognized to mean all signals except those\n\
|
||
used by the debugger, typically SIGTRAP and SIGINT.\n\
|
||
Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
|
||
\"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
|
||
Stop means reenter debugger if this signal happens (implies print).\n\
|
||
Print means print a message if this signal happens.\n\
|
||
Pass means let program see this signal; otherwise program doesn't know.\n\
|
||
Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
|
||
Pass and Stop may be combined."));
|
||
if (xdb_commands)
|
||
{
|
||
add_com ("lz", class_info, signals_info, _("\
|
||
What debugger does when program gets various signals.\n\
|
||
Specify a signal as argument to print info on that signal only."));
|
||
add_com ("z", class_run, xdb_handle_command, _("\
|
||
Specify how to handle a signal.\n\
|
||
Args are signals and actions to apply to those signals.\n\
|
||
Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
|
||
from 1-15 are allowed for compatibility with old versions of GDB.\n\
|
||
Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
|
||
The special arg \"all\" is recognized to mean all signals except those\n\
|
||
used by the debugger, typically SIGTRAP and SIGINT.\n\
|
||
Recognized actions include \"s\" (toggles between stop and nostop), \n\
|
||
\"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
|
||
nopass), \"Q\" (noprint)\n\
|
||
Stop means reenter debugger if this signal happens (implies print).\n\
|
||
Print means print a message if this signal happens.\n\
|
||
Pass means let program see this signal; otherwise program doesn't know.\n\
|
||
Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
|
||
Pass and Stop may be combined."));
|
||
}
|
||
|
||
if (!dbx_commands)
|
||
stop_command = add_cmd ("stop", class_obscure,
|
||
not_just_help_class_command, _("\
|
||
There is no `stop' command, but you can set a hook on `stop'.\n\
|
||
This allows you to set a list of commands to be run each time execution\n\
|
||
of the program stops."), &cmdlist);
|
||
|
||
add_setshow_zinteger_cmd ("infrun", class_maintenance, &debug_infrun, _("\
|
||
Set inferior debugging."), _("\
|
||
Show inferior debugging."), _("\
|
||
When non-zero, inferior specific debugging is enabled."),
|
||
NULL,
|
||
show_debug_infrun,
|
||
&setdebuglist, &showdebuglist);
|
||
|
||
add_setshow_boolean_cmd ("displaced", class_maintenance, &debug_displaced, _("\
|
||
Set displaced stepping debugging."), _("\
|
||
Show displaced stepping debugging."), _("\
|
||
When non-zero, displaced stepping specific debugging is enabled."),
|
||
NULL,
|
||
show_debug_displaced,
|
||
&setdebuglist, &showdebuglist);
|
||
|
||
add_setshow_boolean_cmd ("non-stop", no_class,
|
||
&non_stop_1, _("\
|
||
Set whether gdb controls the inferior in non-stop mode."), _("\
|
||
Show whether gdb controls the inferior in non-stop mode."), _("\
|
||
When debugging a multi-threaded program and this setting is\n\
|
||
off (the default, also called all-stop mode), when one thread stops\n\
|
||
(for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
|
||
all other threads in the program while you interact with the thread of\n\
|
||
interest. When you continue or step a thread, you can allow the other\n\
|
||
threads to run, or have them remain stopped, but while you inspect any\n\
|
||
thread's state, all threads stop.\n\
|
||
\n\
|
||
In non-stop mode, when one thread stops, other threads can continue\n\
|
||
to run freely. You'll be able to step each thread independently,\n\
|
||
leave it stopped or free to run as needed."),
|
||
set_non_stop,
|
||
show_non_stop,
|
||
&setlist,
|
||
&showlist);
|
||
|
||
numsigs = (int) TARGET_SIGNAL_LAST;
|
||
signal_stop = (unsigned char *) xmalloc (sizeof (signal_stop[0]) * numsigs);
|
||
signal_print = (unsigned char *)
|
||
xmalloc (sizeof (signal_print[0]) * numsigs);
|
||
signal_program = (unsigned char *)
|
||
xmalloc (sizeof (signal_program[0]) * numsigs);
|
||
for (i = 0; i < numsigs; i++)
|
||
{
|
||
signal_stop[i] = 1;
|
||
signal_print[i] = 1;
|
||
signal_program[i] = 1;
|
||
}
|
||
|
||
/* Signals caused by debugger's own actions
|
||
should not be given to the program afterwards. */
|
||
signal_program[TARGET_SIGNAL_TRAP] = 0;
|
||
signal_program[TARGET_SIGNAL_INT] = 0;
|
||
|
||
/* Signals that are not errors should not normally enter the debugger. */
|
||
signal_stop[TARGET_SIGNAL_ALRM] = 0;
|
||
signal_print[TARGET_SIGNAL_ALRM] = 0;
|
||
signal_stop[TARGET_SIGNAL_VTALRM] = 0;
|
||
signal_print[TARGET_SIGNAL_VTALRM] = 0;
|
||
signal_stop[TARGET_SIGNAL_PROF] = 0;
|
||
signal_print[TARGET_SIGNAL_PROF] = 0;
|
||
signal_stop[TARGET_SIGNAL_CHLD] = 0;
|
||
signal_print[TARGET_SIGNAL_CHLD] = 0;
|
||
signal_stop[TARGET_SIGNAL_IO] = 0;
|
||
signal_print[TARGET_SIGNAL_IO] = 0;
|
||
signal_stop[TARGET_SIGNAL_POLL] = 0;
|
||
signal_print[TARGET_SIGNAL_POLL] = 0;
|
||
signal_stop[TARGET_SIGNAL_URG] = 0;
|
||
signal_print[TARGET_SIGNAL_URG] = 0;
|
||
signal_stop[TARGET_SIGNAL_WINCH] = 0;
|
||
signal_print[TARGET_SIGNAL_WINCH] = 0;
|
||
|
||
/* These signals are used internally by user-level thread
|
||
implementations. (See signal(5) on Solaris.) Like the above
|
||
signals, a healthy program receives and handles them as part of
|
||
its normal operation. */
|
||
signal_stop[TARGET_SIGNAL_LWP] = 0;
|
||
signal_print[TARGET_SIGNAL_LWP] = 0;
|
||
signal_stop[TARGET_SIGNAL_WAITING] = 0;
|
||
signal_print[TARGET_SIGNAL_WAITING] = 0;
|
||
signal_stop[TARGET_SIGNAL_CANCEL] = 0;
|
||
signal_print[TARGET_SIGNAL_CANCEL] = 0;
|
||
|
||
add_setshow_zinteger_cmd ("stop-on-solib-events", class_support,
|
||
&stop_on_solib_events, _("\
|
||
Set stopping for shared library events."), _("\
|
||
Show stopping for shared library events."), _("\
|
||
If nonzero, gdb will give control to the user when the dynamic linker\n\
|
||
notifies gdb of shared library events. The most common event of interest\n\
|
||
to the user would be loading/unloading of a new library."),
|
||
NULL,
|
||
show_stop_on_solib_events,
|
||
&setlist, &showlist);
|
||
|
||
add_setshow_enum_cmd ("follow-fork-mode", class_run,
|
||
follow_fork_mode_kind_names,
|
||
&follow_fork_mode_string, _("\
|
||
Set debugger response to a program call of fork or vfork."), _("\
|
||
Show debugger response to a program call of fork or vfork."), _("\
|
||
A fork or vfork creates a new process. follow-fork-mode can be:\n\
|
||
parent - the original process is debugged after a fork\n\
|
||
child - the new process is debugged after a fork\n\
|
||
The unfollowed process will continue to run.\n\
|
||
By default, the debugger will follow the parent process."),
|
||
NULL,
|
||
show_follow_fork_mode_string,
|
||
&setlist, &showlist);
|
||
|
||
add_setshow_enum_cmd ("scheduler-locking", class_run,
|
||
scheduler_enums, &scheduler_mode, _("\
|
||
Set mode for locking scheduler during execution."), _("\
|
||
Show mode for locking scheduler during execution."), _("\
|
||
off == no locking (threads may preempt at any time)\n\
|
||
on == full locking (no thread except the current thread may run)\n\
|
||
step == scheduler locked during every single-step operation.\n\
|
||
In this mode, no other thread may run during a step command.\n\
|
||
Other threads may run while stepping over a function call ('next')."),
|
||
set_schedlock_func, /* traps on target vector */
|
||
show_scheduler_mode,
|
||
&setlist, &showlist);
|
||
|
||
add_setshow_boolean_cmd ("step-mode", class_run, &step_stop_if_no_debug, _("\
|
||
Set mode of the step operation."), _("\
|
||
Show mode of the step operation."), _("\
|
||
When set, doing a step over a function without debug line information\n\
|
||
will stop at the first instruction of that function. Otherwise, the\n\
|
||
function is skipped and the step command stops at a different source line."),
|
||
NULL,
|
||
show_step_stop_if_no_debug,
|
||
&setlist, &showlist);
|
||
|
||
add_setshow_enum_cmd ("displaced-stepping", class_run,
|
||
can_use_displaced_stepping_enum,
|
||
&can_use_displaced_stepping, _("\
|
||
Set debugger's willingness to use displaced stepping."), _("\
|
||
Show debugger's willingness to use displaced stepping."), _("\
|
||
If on, gdb will use displaced stepping to step over breakpoints if it is\n\
|
||
supported by the target architecture. If off, gdb will not use displaced\n\
|
||
stepping to step over breakpoints, even if such is supported by the target\n\
|
||
architecture. If auto (which is the default), gdb will use displaced stepping\n\
|
||
if the target architecture supports it and non-stop mode is active, but will not\n\
|
||
use it in all-stop mode (see help set non-stop)."),
|
||
NULL,
|
||
show_can_use_displaced_stepping,
|
||
&setlist, &showlist);
|
||
|
||
add_setshow_enum_cmd ("exec-direction", class_run, exec_direction_names,
|
||
&exec_direction, _("Set direction of execution.\n\
|
||
Options are 'forward' or 'reverse'."),
|
||
_("Show direction of execution (forward/reverse)."),
|
||
_("Tells gdb whether to execute forward or backward."),
|
||
set_exec_direction_func, show_exec_direction_func,
|
||
&setlist, &showlist);
|
||
|
||
/* ptid initializations */
|
||
null_ptid = ptid_build (0, 0, 0);
|
||
minus_one_ptid = ptid_build (-1, 0, 0);
|
||
inferior_ptid = null_ptid;
|
||
target_last_wait_ptid = minus_one_ptid;
|
||
displaced_step_ptid = null_ptid;
|
||
|
||
observer_attach_thread_ptid_changed (infrun_thread_ptid_changed);
|
||
observer_attach_thread_stop_requested (infrun_thread_stop_requested);
|
||
}
|