61012eef84
This commit introduces a new inline common function "startswith" which takes two string arguments and returns nonzero if the first string starts with the second. It also updates the 295 places where this logic was written out longhand to use the new function. gdb/ChangeLog: * common/common-utils.h (startswith): New inline function. All places where this logic was used updated to use the above.
514 lines
14 KiB
C
514 lines
14 KiB
C
/* Target-dependent code for OpenBSD/amd64.
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Copyright (C) 2003-2015 Free Software Foundation, Inc.
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This file is part of GDB.
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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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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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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 "frame.h"
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#include "frame-unwind.h"
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#include "gdbcore.h"
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#include "symtab.h"
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#include "objfiles.h"
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#include "osabi.h"
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#include "regcache.h"
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#include "regset.h"
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#include "target.h"
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#include "trad-frame.h"
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#include "obsd-tdep.h"
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#include "amd64-tdep.h"
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#include "i387-tdep.h"
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#include "solib-svr4.h"
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#include "bsd-uthread.h"
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/* Support for core dumps. */
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static void
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amd64obsd_supply_regset (const struct regset *regset,
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struct regcache *regcache, int regnum,
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const void *regs, size_t len)
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{
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struct gdbarch *gdbarch = get_regcache_arch (regcache);
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const struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
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gdb_assert (len >= tdep->sizeof_gregset + I387_SIZEOF_FXSAVE);
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i386_supply_gregset (regset, regcache, regnum, regs, tdep->sizeof_gregset);
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amd64_supply_fxsave (regcache, regnum,
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((const gdb_byte *)regs) + tdep->sizeof_gregset);
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}
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static const struct regset amd64obsd_combined_regset =
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{
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NULL, amd64obsd_supply_regset, NULL
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};
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static void
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amd64obsd_iterate_over_regset_sections (struct gdbarch *gdbarch,
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iterate_over_regset_sections_cb *cb,
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void *cb_data,
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const struct regcache *regcache)
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{
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struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
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/* OpenBSD core dumps don't use seperate register sets for the
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general-purpose and floating-point registers. */
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cb (".reg", tdep->sizeof_gregset + I387_SIZEOF_FXSAVE,
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&amd64obsd_combined_regset, NULL, cb_data);
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}
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/* Support for signal handlers. */
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/* Default page size. */
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static const int amd64obsd_page_size = 4096;
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/* Return whether THIS_FRAME corresponds to an OpenBSD sigtramp
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routine. */
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static int
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amd64obsd_sigtramp_p (struct frame_info *this_frame)
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{
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CORE_ADDR pc = get_frame_pc (this_frame);
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CORE_ADDR start_pc = (pc & ~(amd64obsd_page_size - 1));
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const gdb_byte osigreturn[] =
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{
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0x48, 0xc7, 0xc0,
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0x67, 0x00, 0x00, 0x00, /* movq $SYS_sigreturn, %rax */
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0xcd, 0x80 /* int $0x80 */
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};
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const gdb_byte sigreturn[] =
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{
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0x48, 0xc7, 0xc0,
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0x67, 0x00, 0x00, 0x00, /* movq $SYS_sigreturn, %rax */
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0x0f, 0x05 /* syscall */
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};
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size_t buflen = (sizeof sigreturn) + 1;
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gdb_byte *buf;
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const char *name;
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/* If the function has a valid symbol name, it isn't a
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trampoline. */
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find_pc_partial_function (pc, &name, NULL, NULL);
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if (name != NULL)
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return 0;
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/* If the function lives in a valid section (even without a starting
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point) it isn't a trampoline. */
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if (find_pc_section (pc) != NULL)
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return 0;
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/* If we can't read the instructions at START_PC, return zero. */
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buf = alloca ((sizeof sigreturn) + 1);
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if (!safe_frame_unwind_memory (this_frame, start_pc + 6, buf, buflen))
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return 0;
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/* Check for sigreturn(2). Depending on how the assembler encoded
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the `movq %rsp, %rdi' instruction, the code starts at offset 6 or
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7. OpenBSD 5.0 and later use the `syscall' instruction. Older
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versions use `int $0x80'. Check for both. */
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if (memcmp (buf, sigreturn, sizeof sigreturn)
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&& memcmp (buf + 1, sigreturn, sizeof sigreturn)
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&& memcmp (buf, osigreturn, sizeof osigreturn)
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&& memcmp (buf + 1, osigreturn, sizeof osigreturn))
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return 0;
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return 1;
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}
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/* Assuming THIS_FRAME is for a BSD sigtramp routine, return the
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address of the associated sigcontext structure. */
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static CORE_ADDR
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amd64obsd_sigcontext_addr (struct frame_info *this_frame)
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{
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CORE_ADDR pc = get_frame_pc (this_frame);
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ULONGEST offset = (pc & (amd64obsd_page_size - 1));
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/* The %rsp register points at `struct sigcontext' upon entry of a
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signal trampoline. The relevant part of the trampoline is
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call *%rax
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movq %rsp, %rdi
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pushq %rdi
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movq $SYS_sigreturn,%rax
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int $0x80
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(see /usr/src/sys/arch/amd64/amd64/locore.S). The `pushq'
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instruction clobbers %rsp, but its value is saved in `%rdi'. */
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if (offset > 5)
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return get_frame_register_unsigned (this_frame, AMD64_RDI_REGNUM);
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else
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return get_frame_register_unsigned (this_frame, AMD64_RSP_REGNUM);
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}
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/* OpenBSD 3.5 or later. */
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/* Mapping between the general-purpose registers in `struct reg'
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format and GDB's register cache layout. */
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/* From <machine/reg.h>. */
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int amd64obsd_r_reg_offset[] =
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{
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14 * 8, /* %rax */
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13 * 8, /* %rbx */
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3 * 8, /* %rcx */
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2 * 8, /* %rdx */
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1 * 8, /* %rsi */
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0 * 8, /* %rdi */
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12 * 8, /* %rbp */
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15 * 8, /* %rsp */
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4 * 8, /* %r8 .. */
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5 * 8,
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6 * 8,
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7 * 8,
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8 * 8,
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9 * 8,
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10 * 8,
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11 * 8, /* ... %r15 */
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16 * 8, /* %rip */
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17 * 8, /* %eflags */
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18 * 8, /* %cs */
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19 * 8, /* %ss */
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20 * 8, /* %ds */
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21 * 8, /* %es */
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22 * 8, /* %fs */
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23 * 8 /* %gs */
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};
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/* From <machine/signal.h>. */
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static int amd64obsd_sc_reg_offset[] =
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{
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14 * 8, /* %rax */
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13 * 8, /* %rbx */
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3 * 8, /* %rcx */
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2 * 8, /* %rdx */
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1 * 8, /* %rsi */
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0 * 8, /* %rdi */
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12 * 8, /* %rbp */
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24 * 8, /* %rsp */
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4 * 8, /* %r8 ... */
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5 * 8,
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6 * 8,
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7 * 8,
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8 * 8,
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9 * 8,
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10 * 8,
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11 * 8, /* ... %r15 */
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21 * 8, /* %rip */
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23 * 8, /* %eflags */
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22 * 8, /* %cs */
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25 * 8, /* %ss */
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18 * 8, /* %ds */
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17 * 8, /* %es */
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16 * 8, /* %fs */
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15 * 8 /* %gs */
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};
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/* From /usr/src/lib/libpthread/arch/amd64/uthread_machdep.c. */
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static int amd64obsd_uthread_reg_offset[] =
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{
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19 * 8, /* %rax */
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16 * 8, /* %rbx */
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18 * 8, /* %rcx */
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17 * 8, /* %rdx */
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14 * 8, /* %rsi */
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13 * 8, /* %rdi */
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15 * 8, /* %rbp */
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-1, /* %rsp */
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12 * 8, /* %r8 ... */
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11 * 8,
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10 * 8,
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9 * 8,
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8 * 8,
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7 * 8,
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6 * 8,
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5 * 8, /* ... %r15 */
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20 * 8, /* %rip */
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4 * 8, /* %eflags */
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21 * 8, /* %cs */
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-1, /* %ss */
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3 * 8, /* %ds */
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2 * 8, /* %es */
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1 * 8, /* %fs */
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0 * 8 /* %gs */
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};
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/* Offset within the thread structure where we can find the saved
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stack pointer (%esp). */
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#define AMD64OBSD_UTHREAD_RSP_OFFSET 400
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static void
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amd64obsd_supply_uthread (struct regcache *regcache,
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int regnum, CORE_ADDR addr)
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{
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struct gdbarch *gdbarch = get_regcache_arch (regcache);
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enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
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CORE_ADDR sp_addr = addr + AMD64OBSD_UTHREAD_RSP_OFFSET;
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CORE_ADDR sp = 0;
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gdb_byte buf[8];
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int i;
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gdb_assert (regnum >= -1);
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if (regnum == -1 || regnum == AMD64_RSP_REGNUM)
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{
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int offset;
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/* Fetch stack pointer from thread structure. */
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sp = read_memory_unsigned_integer (sp_addr, 8, byte_order);
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/* Adjust the stack pointer such that it looks as if we just
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returned from _thread_machdep_switch. */
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offset = amd64obsd_uthread_reg_offset[AMD64_RIP_REGNUM] + 8;
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store_unsigned_integer (buf, 8, byte_order, sp + offset);
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regcache_raw_supply (regcache, AMD64_RSP_REGNUM, buf);
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}
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for (i = 0; i < ARRAY_SIZE (amd64obsd_uthread_reg_offset); i++)
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{
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if (amd64obsd_uthread_reg_offset[i] != -1
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&& (regnum == -1 || regnum == i))
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{
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/* Fetch stack pointer from thread structure (if we didn't
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do so already). */
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if (sp == 0)
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sp = read_memory_unsigned_integer (sp_addr, 8, byte_order);
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/* Read the saved register from the stack frame. */
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read_memory (sp + amd64obsd_uthread_reg_offset[i], buf, 8);
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regcache_raw_supply (regcache, i, buf);
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}
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}
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}
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static void
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amd64obsd_collect_uthread (const struct regcache *regcache,
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int regnum, CORE_ADDR addr)
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{
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struct gdbarch *gdbarch = get_regcache_arch (regcache);
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enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
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CORE_ADDR sp_addr = addr + AMD64OBSD_UTHREAD_RSP_OFFSET;
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CORE_ADDR sp = 0;
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gdb_byte buf[8];
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int i;
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gdb_assert (regnum >= -1);
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if (regnum == -1 || regnum == AMD64_RSP_REGNUM)
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{
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int offset;
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/* Calculate the stack pointer (frame pointer) that will be
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stored into the thread structure. */
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offset = amd64obsd_uthread_reg_offset[AMD64_RIP_REGNUM] + 8;
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regcache_raw_collect (regcache, AMD64_RSP_REGNUM, buf);
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sp = extract_unsigned_integer (buf, 8, byte_order) - offset;
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/* Store the stack pointer. */
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write_memory_unsigned_integer (sp_addr, 8, byte_order, sp);
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/* The stack pointer was (potentially) modified. Make sure we
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build a proper stack frame. */
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regnum = -1;
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}
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for (i = 0; i < ARRAY_SIZE (amd64obsd_uthread_reg_offset); i++)
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{
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if (amd64obsd_uthread_reg_offset[i] != -1
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&& (regnum == -1 || regnum == i))
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{
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/* Fetch stack pointer from thread structure (if we didn't
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calculate it already). */
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if (sp == 0)
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sp = read_memory_unsigned_integer (sp_addr, 8, byte_order);
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/* Write the register into the stack frame. */
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regcache_raw_collect (regcache, i, buf);
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write_memory (sp + amd64obsd_uthread_reg_offset[i], buf, 8);
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}
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}
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}
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/* Kernel debugging support. */
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/* From <machine/frame.h>. Easy since `struct trapframe' matches
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`struct sigcontext'. */
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#define amd64obsd_tf_reg_offset amd64obsd_sc_reg_offset
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static struct trad_frame_cache *
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amd64obsd_trapframe_cache (struct frame_info *this_frame, void **this_cache)
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{
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struct gdbarch *gdbarch = get_frame_arch (this_frame);
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enum bfd_endian byte_order = gdbarch_byte_order (gdbarch);
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struct trad_frame_cache *cache;
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CORE_ADDR func, sp, addr;
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ULONGEST cs;
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const char *name;
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int i;
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if (*this_cache)
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return *this_cache;
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cache = trad_frame_cache_zalloc (this_frame);
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*this_cache = cache;
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func = get_frame_func (this_frame);
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sp = get_frame_register_unsigned (this_frame, AMD64_RSP_REGNUM);
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find_pc_partial_function (func, &name, NULL, NULL);
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if (name && startswith (name, "Xintr"))
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addr = sp + 8; /* It's an interrupt frame. */
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else
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addr = sp;
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for (i = 0; i < ARRAY_SIZE (amd64obsd_tf_reg_offset); i++)
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if (amd64obsd_tf_reg_offset[i] != -1)
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trad_frame_set_reg_addr (cache, i, addr + amd64obsd_tf_reg_offset[i]);
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/* Read %cs from trap frame. */
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addr += amd64obsd_tf_reg_offset[AMD64_CS_REGNUM];
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cs = read_memory_unsigned_integer (addr, 8, byte_order);
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if ((cs & I386_SEL_RPL) == I386_SEL_UPL)
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{
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/* Trap from user space; terminate backtrace. */
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trad_frame_set_id (cache, outer_frame_id);
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}
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else
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{
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/* Construct the frame ID using the function start. */
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trad_frame_set_id (cache, frame_id_build (sp + 16, func));
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}
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return cache;
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}
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static void
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amd64obsd_trapframe_this_id (struct frame_info *this_frame,
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void **this_cache, struct frame_id *this_id)
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{
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struct trad_frame_cache *cache =
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amd64obsd_trapframe_cache (this_frame, this_cache);
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trad_frame_get_id (cache, this_id);
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}
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static struct value *
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amd64obsd_trapframe_prev_register (struct frame_info *this_frame,
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void **this_cache, int regnum)
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{
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struct trad_frame_cache *cache =
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amd64obsd_trapframe_cache (this_frame, this_cache);
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return trad_frame_get_register (cache, this_frame, regnum);
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}
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static int
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amd64obsd_trapframe_sniffer (const struct frame_unwind *self,
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struct frame_info *this_frame,
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void **this_prologue_cache)
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{
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ULONGEST cs;
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const char *name;
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/* Check Current Privilege Level and bail out if we're not executing
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in kernel space. */
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cs = get_frame_register_unsigned (this_frame, AMD64_CS_REGNUM);
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if ((cs & I386_SEL_RPL) == I386_SEL_UPL)
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return 0;
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find_pc_partial_function (get_frame_pc (this_frame), &name, NULL, NULL);
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return (name && ((strcmp (name, "calltrap") == 0)
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|| (strcmp (name, "osyscall1") == 0)
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|| (strcmp (name, "Xsyscall") == 0)
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|| (startswith (name, "Xintr"))));
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}
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static const struct frame_unwind amd64obsd_trapframe_unwind = {
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/* FIXME: kettenis/20051219: This really is more like an interrupt
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frame, but SIGTRAMP_FRAME would print <signal handler called>,
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which really is not what we want here. */
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NORMAL_FRAME,
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default_frame_unwind_stop_reason,
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amd64obsd_trapframe_this_id,
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amd64obsd_trapframe_prev_register,
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NULL,
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amd64obsd_trapframe_sniffer
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};
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static void
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amd64obsd_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
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{
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struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
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amd64_init_abi (info, gdbarch);
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obsd_init_abi (info, gdbarch);
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/* Initialize general-purpose register set details. */
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tdep->gregset_reg_offset = amd64obsd_r_reg_offset;
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tdep->gregset_num_regs = ARRAY_SIZE (amd64obsd_r_reg_offset);
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tdep->sizeof_gregset = 24 * 8;
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tdep->jb_pc_offset = 7 * 8;
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tdep->sigtramp_p = amd64obsd_sigtramp_p;
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tdep->sigcontext_addr = amd64obsd_sigcontext_addr;
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tdep->sc_reg_offset = amd64obsd_sc_reg_offset;
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tdep->sc_num_regs = ARRAY_SIZE (amd64obsd_sc_reg_offset);
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/* OpenBSD provides a user-level threads implementation. */
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bsd_uthread_set_supply_uthread (gdbarch, amd64obsd_supply_uthread);
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bsd_uthread_set_collect_uthread (gdbarch, amd64obsd_collect_uthread);
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/* OpenBSD uses SVR4-style shared libraries. */
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set_solib_svr4_fetch_link_map_offsets
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(gdbarch, svr4_lp64_fetch_link_map_offsets);
|
||
|
||
/* Unwind kernel trap frames correctly. */
|
||
frame_unwind_prepend_unwinder (gdbarch, &amd64obsd_trapframe_unwind);
|
||
}
|
||
|
||
/* Traditional (a.out) NetBSD-style core dumps. */
|
||
|
||
static void
|
||
amd64obsd_core_init_abi (struct gdbarch_info info, struct gdbarch *gdbarch)
|
||
{
|
||
amd64obsd_init_abi (info, gdbarch);
|
||
|
||
set_gdbarch_iterate_over_regset_sections
|
||
(gdbarch, amd64obsd_iterate_over_regset_sections);
|
||
}
|
||
|
||
|
||
/* Provide a prototype to silence -Wmissing-prototypes. */
|
||
void _initialize_amd64obsd_tdep (void);
|
||
|
||
void
|
||
_initialize_amd64obsd_tdep (void)
|
||
{
|
||
/* The OpenBSD/amd64 native dependent code makes this assumption. */
|
||
gdb_assert (ARRAY_SIZE (amd64obsd_r_reg_offset) == AMD64_NUM_GREGS);
|
||
|
||
gdbarch_register_osabi (bfd_arch_i386, bfd_mach_x86_64,
|
||
GDB_OSABI_OPENBSD_ELF, amd64obsd_init_abi);
|
||
|
||
/* OpenBSD uses traditional (a.out) NetBSD-style core dumps. */
|
||
gdbarch_register_osabi (bfd_arch_i386, bfd_mach_x86_64,
|
||
GDB_OSABI_NETBSD_AOUT, amd64obsd_core_init_abi);
|
||
}
|