6fe90fc83f
or "the program being debugged". * inflow.c (try_writing_regs): Remove; it's been #if 0'd forever and I'm getting sick of maintaining it.
370 lines
11 KiB
C
370 lines
11 KiB
C
/* Low level Pyramid interface to ptrace, for GDB when running under Unix.
|
||
Copyright (C) 1988, 1989, 1991 Free Software Foundation, Inc.
|
||
|
||
This file is part of GDB.
|
||
|
||
This program is free software; you can redistribute it and/or modify
|
||
it under the terms of the GNU General Public License as published by
|
||
the Free Software Foundation; either version 2 of the License, or
|
||
(at your option) any later version.
|
||
|
||
This program is distributed in the hope that it will be useful,
|
||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
||
GNU General Public License for more details.
|
||
|
||
You should have received a copy of the GNU General Public License
|
||
along with this program; if not, write to the Free Software
|
||
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
|
||
|
||
#include "defs.h"
|
||
#include "frame.h"
|
||
#include "inferior.h"
|
||
|
||
#include <sys/param.h>
|
||
#include <sys/dir.h>
|
||
#include <signal.h>
|
||
#include <sys/ioctl.h>
|
||
/* #include <fcntl.h> Can we live without this? */
|
||
|
||
#include "gdbcore.h"
|
||
#include <sys/user.h> /* After a.out.h */
|
||
#include <sys/file.h>
|
||
#include <sys/stat.h>
|
||
|
||
|
||
void
|
||
fetch_inferior_registers (regno)
|
||
int regno;
|
||
{
|
||
register int datum;
|
||
register unsigned int regaddr;
|
||
int reg_buf[NUM_REGS+1];
|
||
struct user u;
|
||
register int skipped_frames = 0;
|
||
|
||
registers_fetched ();
|
||
|
||
for (regno = 0; regno < 64; regno++) {
|
||
reg_buf[regno] = ptrace (3, inferior_pid, (PTRACE_ARG3_TYPE) regno, 0);
|
||
|
||
#if defined(PYRAMID_CONTROL_FRAME_DEBUGGING)
|
||
printf ("Fetching register %s, got %0x\n",
|
||
reg_names[regno],
|
||
reg_buf[regno]);
|
||
#endif /* PYRAMID_CONTROL_FRAME_DEBUGGING */
|
||
|
||
if (reg_buf[regno] == -1 && errno == EIO) {
|
||
printf("fetch_interior_registers: fetching register %s\n",
|
||
reg_names[regno]);
|
||
errno = 0;
|
||
}
|
||
supply_register (regno, reg_buf+regno);
|
||
}
|
||
/* that leaves regs 64, 65, and 66 */
|
||
datum = ptrace (3, inferior_pid,
|
||
(PTRACE_ARG3_TYPE) (((char *)&u.u_pcb.pcb_csp) -
|
||
((char *)&u)), 0);
|
||
|
||
|
||
|
||
/* FIXME: Find the Current Frame Pointer (CFP). CFP is a global
|
||
register (ie, NOT windowed), that gets saved in a frame iff
|
||
the code for that frame has a prologue (ie, "adsf N"). If
|
||
there is a prologue, the adsf insn saves the old cfp in
|
||
pr13, cfp is set to sp, and N bytes of locals are allocated
|
||
(sp is decremented by n).
|
||
This makes finding CFP hard. I guess the right way to do it
|
||
is:
|
||
- If this is the innermost frame, believe ptrace() or
|
||
the core area.
|
||
- Otherwise:
|
||
Find the first insn of the current frame.
|
||
- find the saved pc;
|
||
- find the call insn that saved it;
|
||
- figure out where the call is to;
|
||
- if the first insn is an adsf, we got a frame
|
||
pointer. */
|
||
|
||
|
||
/* Normal processors have separate stack pointers for user and
|
||
kernel mode. Getting the last user mode frame on such
|
||
machines is easy: the kernel context of the ptrace()'d
|
||
process is on the kernel stack, and the USP points to what
|
||
we want. But Pyramids only have a single cfp for both user and
|
||
kernel mode. And processes being ptrace()'d have some
|
||
kernel-context control frames on their stack.
|
||
To avoid tracing back into the kernel context of an inferior,
|
||
we skip 0 or more contiguous control frames where the pc is
|
||
in the kernel. */
|
||
|
||
while (1) {
|
||
register int inferior_saved_pc;
|
||
inferior_saved_pc = ptrace (1, inferior_pid,
|
||
(PTRACE_ARG3_TYPE) (datum+((32+15)*4)), 0);
|
||
if (inferior_saved_pc > 0) break;
|
||
#if defined(PYRAMID_CONTROL_FRAME_DEBUGGING)
|
||
printf("skipping kernel frame %08x, pc=%08x\n", datum,
|
||
inferior_saved_pc);
|
||
#endif /* PYRAMID_CONTROL_FRAME_DEBUGGING */
|
||
skipped_frames++;
|
||
datum -= CONTROL_STACK_FRAME_SIZE;
|
||
}
|
||
|
||
reg_buf[CSP_REGNUM] = datum;
|
||
supply_register(CSP_REGNUM, reg_buf+CSP_REGNUM);
|
||
#ifdef PYRAMID_CONTROL_FRAME_DEBUGGING
|
||
if (skipped_frames) {
|
||
fprintf (stderr,
|
||
"skipped %d frames from %x to %x; cfp was %x, now %x\n",
|
||
skipped_frames, reg_buf[CSP_REGNUM]);
|
||
}
|
||
#endif /* PYRAMID_CONTROL_FRAME_DEBUGGING */
|
||
}
|
||
|
||
/* Store our register values back into the inferior.
|
||
If REGNO is -1, do this for all registers.
|
||
Otherwise, REGNO specifies which register (so we can save time). */
|
||
|
||
void
|
||
store_inferior_registers (regno)
|
||
int regno;
|
||
{
|
||
register unsigned int regaddr;
|
||
char buf[80];
|
||
|
||
if (regno >= 0)
|
||
{
|
||
if ((0 <= regno) && (regno < 64)) {
|
||
/*regaddr = register_addr (regno, offset);*/
|
||
regaddr = regno;
|
||
errno = 0;
|
||
ptrace (6, inferior_pid, (PTRACE_ARG3_TYPE) regaddr,
|
||
read_register (regno));
|
||
if (errno != 0)
|
||
{
|
||
sprintf (buf, "writing register number %d", regno);
|
||
perror_with_name (buf);
|
||
}
|
||
}
|
||
}
|
||
else
|
||
{
|
||
for (regno = 0; regno < NUM_REGS; regno++)
|
||
{
|
||
/*regaddr = register_addr (regno, offset);*/
|
||
regaddr = regno;
|
||
errno = 0;
|
||
ptrace (6, inferior_pid, (PTRACE_ARG3_TYPE) regaddr,
|
||
read_register (regno));
|
||
if (errno != 0)
|
||
{
|
||
sprintf (buf, "writing all regs, number %d", regno);
|
||
perror_with_name (buf);
|
||
}
|
||
}
|
||
}
|
||
|
||
/*** Extensions to core and dump files, for GDB. */
|
||
|
||
extern unsigned int last_frame_offset;
|
||
|
||
#ifdef PYRAMID_CORE
|
||
|
||
/* Can't make definitions here static, since core.c needs them
|
||
to do bounds checking on the core-file areas. O well. */
|
||
|
||
/* have two stacks: one for data, one for register windows. */
|
||
extern CORE_ADDR reg_stack_start;
|
||
extern CORE_ADDR reg_stack_end;
|
||
|
||
/* need this so we can find the global registers: they never get saved. */
|
||
CORE_ADDR global_reg_offset;
|
||
static CORE_ADDR last_frame_address;
|
||
CORE_ADDR last_frame_offset;
|
||
|
||
|
||
/* Address in core file of start of register window stack area.
|
||
Don't know if is this any of meaningful, useful or necessary. */
|
||
extern int reg_stack_offset;
|
||
|
||
#endif /* PYRAMID_CORE */
|
||
|
||
|
||
/* Work with core dump and executable files, for GDB.
|
||
This code would be in core.c if it weren't machine-dependent. */
|
||
|
||
void
|
||
core_file_command (filename, from_tty)
|
||
char *filename;
|
||
int from_tty;
|
||
{
|
||
int val;
|
||
extern char registers[];
|
||
|
||
/* Discard all vestiges of any previous core file
|
||
and mark data and stack spaces as empty. */
|
||
|
||
if (corefile)
|
||
free (corefile);
|
||
corefile = 0;
|
||
|
||
if (corechan >= 0)
|
||
close (corechan);
|
||
corechan = -1;
|
||
|
||
data_start = 0;
|
||
data_end = 0;
|
||
stack_start = STACK_END_ADDR;
|
||
stack_end = STACK_END_ADDR;
|
||
|
||
#ifdef PYRAMID_CORE
|
||
reg_stack_start = CONTROL_STACK_ADDR;
|
||
reg_stack_end = CONTROL_STACK_ADDR; /* this isn't strictly true...*/
|
||
#endif /* PYRAMID_CORE */
|
||
|
||
/* Now, if a new core file was specified, open it and digest it. */
|
||
|
||
if (filename)
|
||
{
|
||
filename = tilde_expand (filename);
|
||
make_cleanup (free, filename);
|
||
|
||
if (have_inferior_p ())
|
||
error ("To look at a core file, you must kill the program with \"kill\".");
|
||
corechan = open (filename, O_RDONLY, 0);
|
||
if (corechan < 0)
|
||
perror_with_name (filename);
|
||
/* 4.2-style (and perhaps also sysV-style) core dump file. */
|
||
{
|
||
struct user u;
|
||
|
||
unsigned int reg_offset;
|
||
|
||
val = myread (corechan, &u, sizeof u);
|
||
if (val < 0)
|
||
perror_with_name ("Not a core file: reading upage");
|
||
if (val != sizeof u)
|
||
error ("Not a core file: could only read %d bytes", val);
|
||
data_start = exec_data_start;
|
||
|
||
data_end = data_start + NBPG * u.u_dsize;
|
||
data_offset = NBPG * UPAGES;
|
||
stack_offset = NBPG * (UPAGES + u.u_dsize);
|
||
|
||
/* find registers in core file */
|
||
#ifdef PYRAMID_PTRACE
|
||
stack_start = stack_end - NBPG * u.u_ussize;
|
||
reg_stack_offset = stack_offset + (NBPG *u.u_ussize);
|
||
reg_stack_end = reg_stack_start + NBPG * u.u_cssize;
|
||
|
||
last_frame_address = ((int) u.u_pcb.pcb_csp);
|
||
last_frame_offset = reg_stack_offset + last_frame_address
|
||
- CONTROL_STACK_ADDR ;
|
||
global_reg_offset = (char *)&u - (char *)&u.u_pcb.pcb_gr0 ;
|
||
|
||
/* skip any control-stack frames that were executed in the
|
||
kernel. */
|
||
|
||
while (1) {
|
||
char buf[4];
|
||
val = lseek (corechan, last_frame_offset+(47*4), 0);
|
||
if (val < 0)
|
||
perror_with_name (filename);
|
||
val = myread (corechan, buf, sizeof buf);
|
||
if (val < 0)
|
||
perror_with_name (filename);
|
||
|
||
if (*(int *)buf >= 0)
|
||
break;
|
||
printf ("skipping frame %s\n", local_hex_string (last_frame_address));
|
||
last_frame_offset -= CONTROL_STACK_FRAME_SIZE;
|
||
last_frame_address -= CONTROL_STACK_FRAME_SIZE;
|
||
}
|
||
reg_offset = last_frame_offset;
|
||
|
||
#if 1 || defined(PYRAMID_CONTROL_FRAME_DEBUGGING)
|
||
printf ("Control stack pointer = %s\n",
|
||
local_hex_string (u.u_pcb.pcb_csp));
|
||
printf ("offset to control stack %d outermost frame %d (%s)\n",
|
||
reg_stack_offset, reg_offset, local_hex_string (last_frame_address));
|
||
#endif /* PYRAMID_CONTROL_FRAME_DEBUGGING */
|
||
|
||
#else /* not PYRAMID_CORE */
|
||
stack_start = stack_end - NBPG * u.u_ssize;
|
||
reg_offset = (int) u.u_ar0 - KERNEL_U_ADDR;
|
||
#endif /* not PYRAMID_CORE */
|
||
|
||
#ifdef __not_on_pyr_yet
|
||
/* Some machines put an absolute address in here and some put
|
||
the offset in the upage of the regs. */
|
||
reg_offset = (int) u.u_ar0;
|
||
if (reg_offset > NBPG * UPAGES)
|
||
reg_offset -= KERNEL_U_ADDR;
|
||
#endif
|
||
|
||
/* I don't know where to find this info.
|
||
So, for now, mark it as not available. */
|
||
N_SET_MAGIC (core_aouthdr, 0);
|
||
|
||
/* Read the register values out of the core file and store
|
||
them where `read_register' will find them. */
|
||
|
||
{
|
||
register int regno;
|
||
|
||
for (regno = 0; regno < 64; regno++)
|
||
{
|
||
char buf[MAX_REGISTER_RAW_SIZE];
|
||
|
||
val = lseek (corechan, register_addr (regno, reg_offset), 0);
|
||
if (val < 0
|
||
|| (val = myread (corechan, buf, sizeof buf)) < 0)
|
||
{
|
||
char * buffer = (char *) alloca (strlen (reg_names[regno])
|
||
+ 30);
|
||
strcpy (buffer, "Reading register ");
|
||
strcat (buffer, reg_names[regno]);
|
||
|
||
perror_with_name (buffer);
|
||
}
|
||
|
||
if (val < 0)
|
||
perror_with_name (filename);
|
||
#ifdef PYRAMID_CONTROL_FRAME_DEBUGGING
|
||
printf ("[reg %s(%d), offset in file %s=0x%0x, addr =0x%0x, =%0x]\n",
|
||
reg_names[regno], regno, filename,
|
||
register_addr(regno, reg_offset),
|
||
regno * 4 + last_frame_address,
|
||
*((int *)buf));
|
||
#endif /* PYRAMID_CONTROL_FRAME_DEBUGGING */
|
||
supply_register (regno, buf);
|
||
}
|
||
}
|
||
}
|
||
if (filename[0] == '/')
|
||
corefile = savestring (filename, strlen (filename));
|
||
else
|
||
{
|
||
corefile = concat (current_directory, "/", filename, NULL);
|
||
}
|
||
|
||
#if 1 || defined(PYRAMID_CONTROL_FRAME_DEBUGGING)
|
||
printf ("Providing CSP (%s) as nominal address of current frame.\n",
|
||
local_hex_string(last_frame_address));
|
||
#endif PYRAMID_CONTROL_FRAME_DEBUGGING
|
||
/* FIXME: Which of the following is correct? */
|
||
#if 0
|
||
set_current_frame ( create_new_frame (read_register (FP_REGNUM),
|
||
read_pc ()));
|
||
#else
|
||
set_current_frame ( create_new_frame (last_frame_address,
|
||
read_pc ()));
|
||
#endif
|
||
|
||
select_frame (get_current_frame (), 0);
|
||
validate_files ();
|
||
}
|
||
else if (from_tty)
|
||
printf ("No core file now.\n");
|
||
}
|