mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-22 13:00:06 +00:00
117 lines
3.2 KiB
C
117 lines
3.2 KiB
C
/* Return backtrace of current program state.
|
|
Copyright (C) 1998-2023 Free Software Foundation, Inc.
|
|
This file is part of the GNU C Library.
|
|
|
|
The GNU C Library is free software; you can redistribute it and/or
|
|
modify it under the terms of the GNU Lesser General Public
|
|
License as published by the Free Software Foundation; either
|
|
version 2.1 of the License, or (at your option) any later version.
|
|
|
|
The GNU C Library 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
|
|
Lesser General Public License for more details.
|
|
|
|
You should have received a copy of the GNU Lesser General Public
|
|
License along with the GNU C Library; if not, see
|
|
<https://www.gnu.org/licenses/>. */
|
|
|
|
#include <execinfo.h>
|
|
#include <stdlib.h>
|
|
#include <unwind-link.h>
|
|
|
|
struct trace_arg
|
|
{
|
|
void **array;
|
|
struct unwind_link *unwind_link;
|
|
int cnt, size;
|
|
void *lastebp, *lastesp;
|
|
};
|
|
|
|
static _Unwind_Reason_Code
|
|
backtrace_helper (struct _Unwind_Context *ctx, void *a)
|
|
{
|
|
struct trace_arg *arg = a;
|
|
|
|
/* We are first called with address in the __backtrace function.
|
|
Skip it. */
|
|
if (arg->cnt != -1)
|
|
arg->array[arg->cnt]
|
|
= (void *) UNWIND_LINK_PTR (arg->unwind_link, _Unwind_GetIP) (ctx);
|
|
if (++arg->cnt == arg->size)
|
|
return _URC_END_OF_STACK;
|
|
|
|
/* %ebp is DWARF2 register 5 on IA-32. */
|
|
arg->lastebp
|
|
= (void *) UNWIND_LINK_PTR (arg->unwind_link, _Unwind_GetGR) (ctx, 5);
|
|
arg->lastesp
|
|
= (void *) UNWIND_LINK_PTR (arg->unwind_link, _Unwind_GetCFA) (ctx);
|
|
return _URC_NO_REASON;
|
|
}
|
|
|
|
|
|
/* This is a global variable set at program start time. It marks the
|
|
highest used stack address. */
|
|
extern void *__libc_stack_end;
|
|
|
|
|
|
/* This is the stack layout we see with every stack frame
|
|
if not compiled without frame pointer.
|
|
|
|
+-----------------+ +-----------------+
|
|
%ebp -> | %ebp last frame--------> | %ebp last frame--->...
|
|
| | | |
|
|
| return address | | return address |
|
|
+-----------------+ +-----------------+
|
|
|
|
First try as far to get as far as possible using
|
|
_Unwind_Backtrace which handles -fomit-frame-pointer
|
|
as well, but requires .eh_frame info. Then fall back to
|
|
walking the stack manually. */
|
|
|
|
struct layout
|
|
{
|
|
struct layout *ebp;
|
|
void *ret;
|
|
};
|
|
|
|
|
|
int
|
|
__backtrace (void **array, int size)
|
|
{
|
|
struct trace_arg arg =
|
|
{
|
|
.array = array,
|
|
.unwind_link = __libc_unwind_link_get (),
|
|
.size = size,
|
|
.cnt = -1,
|
|
};
|
|
|
|
if (size <= 0 || arg.unwind_link == NULL)
|
|
return 0;
|
|
|
|
UNWIND_LINK_PTR (arg.unwind_link, _Unwind_Backtrace)
|
|
(backtrace_helper, &arg);
|
|
|
|
if (arg.cnt > 1 && arg.array[arg.cnt - 1] == NULL)
|
|
--arg.cnt;
|
|
else if (arg.cnt < size)
|
|
{
|
|
struct layout *ebp = (struct layout *) arg.lastebp;
|
|
|
|
while (arg.cnt < size)
|
|
{
|
|
/* Check for out of range. */
|
|
if ((void *) ebp < arg.lastesp || (void *) ebp > __libc_stack_end
|
|
|| ((long) ebp & 3))
|
|
break;
|
|
|
|
array[arg.cnt++] = ebp->ret;
|
|
ebp = ebp->ebp;
|
|
}
|
|
}
|
|
return arg.cnt != -1 ? arg.cnt : 0;
|
|
}
|
|
weak_alias (__backtrace, backtrace)
|
|
libc_hidden_def (__backtrace)
|