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/* Return backtrace of current program state.
Copyright (C) 1998 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <execinfo.h>
/* 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 alyout we see with every stack frame.
+-----------------+ +-----------------+
%ebp -> | %ebp last frame--------> | %ebp last frame--->...
| | | |
| return address | | return address |
+-----------------+ +-----------------+
*/
struct layout
{
struct layout *next;
void *return_address;
};
int
__backtrace (array, size)
void **array;
int size;
{
/* We assume that all the code is generated with frame pointers set. */
register void *ebp __asm__ ("ebp");
register void *esp __asm__ ("esp");
struct layout *current;
int cnt = 0;
/* We skip the call to this function, it makes no sense to record it. */
current = (struct layout *) ebp;
while (cnt < size)
{
if (current < esp || current > __libc_stack_end)
/* This means the address is out of range. Note that for the
toplevel we see a frame pointer with value NULL which clearly is
out of range. */
break;
array[cnt++] = current->return_address;
current = current->next;
}
return cnt;
}
weak_alias (__backtrace, backtrace)
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