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/* Determine the virtual memory area of a given address. FreeBSD version.
Copyright (C) 2002-2003, 2006, 2008 Bruno Haible <bruno@clisp.org>
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, 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
#include "stackvma.h"
#include <stdio.h>
#include "stackvma-simple.c"
#include "stackvma-rofile.c"
#if HAVE_MINCORE
# define sigsegv_get_vma mincore_get_vma
# define STATIC static
# include "stackvma-mincore.c"
# undef sigsegv_get_vma
#endif
int
sigsegv_get_vma (unsigned long address, struct vma_struct *vma)
{
struct rofile rof;
int c;
/* The stack appears as multiple adjacents segments, therefore we
merge adjacent segments. */
unsigned long next_start, next_end, curr_start, curr_end;
#if STACK_DIRECTION < 0
unsigned long prev_end;
#endif
/* Open the current process' maps file. It describes one VMA per line. */
if (rof_open (&rof, "/proc/curproc/map") < 0)
goto failed;
#if STACK_DIRECTION < 0
prev_end = 0;
#endif
for (curr_start = curr_end = 0; ;)
{
if (!(rof_getchar (&rof) == '0'
&& rof_getchar (&rof) == 'x'
&& rof_scanf_lx (&rof, &next_start) >= 0))
break;
while (c = rof_peekchar (&rof), c == ' ' || c == '\t')
rof_getchar (&rof);
if (!(rof_getchar (&rof) == '0'
&& rof_getchar (&rof) == 'x'
&& rof_scanf_lx (&rof, &next_end) >= 0))
break;
while (c = rof_getchar (&rof), c != -1 && c != '\n')
continue;
if (next_start == curr_end)
{
/* Merge adjacent segments. */
curr_end = next_end;
}
else
{
if (curr_start < curr_end
&& address >= curr_start && address <= curr_end-1)
goto found;
#if STACK_DIRECTION < 0
prev_end = curr_end;
#endif
curr_start = next_start; curr_end = next_end;
}
}
if (address >= curr_start && address <= curr_end-1)
found:
{
vma->start = curr_start;
vma->end = curr_end;
#if STACK_DIRECTION < 0
vma->prev_end = prev_end;
#else
if (rof_getchar (&rof) == '0'
&& rof_getchar (&rof) == 'x'
&& rof_scanf_lx (&rof, &vma->next_start) >= 0)
{
while (c = rof_peekchar (&rof), c == ' ' || c == '\t')
rof_getchar (&rof);
if (rof_getchar (&rof) == '0'
&& rof_getchar (&rof) == 'x'
&& rof_scanf_lx (&rof, &next_end) >= 0)
;
else
vma->next_start = 0;
}
else
vma->next_start = 0;
#endif
rof_close (&rof);
vma->is_near_this = simple_is_near_this;
return 0;
}
rof_close (&rof);
failed:
#if HAVE_MINCORE
/* FreeBSD 6.[01] doesn't allow to distinguish unmapped pages from
mapped but swapped-out pages. See whether it's fixed. */
if (!is_mapped (0))
/* OK, mincore() appears to work as expected. */
return mincore_get_vma (address, vma);
#endif
return -1;
}
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