src/stackvma-netbsd.c

   1 /* Determine the virtual memory area of a given address.  NetBSD version.
   2    Copyright (C) 2002-2003, 2006, 2008, 2011  Bruno Haible <bruno@clisp.org>
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 2, or (at your option)
   7    any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; if not, write to the Free Software Foundation,
  16    Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
  17
  18 #include "stackvma.h"
  19 #include <stdio.h>
  20
  21 #include "stackvma-simple.c"
  22 #include "stackvma-rofile.c"
  23
  24 #if HAVE_MINCORE
  25 # define sigsegv_get_vma mincore_get_vma
  26 # define STATIC static
  27 # include "stackvma-mincore.c"
  28 # undef sigsegv_get_vma
  29 #endif
  30
  31 int
  32 sigsegv_get_vma (unsigned long address, struct vma_struct *vma)
  33 {
  34   struct rofile rof;
  35   int c;
  36   /* The stack appears as multiple adjacents segments, therefore we
  37      merge adjacent segments.  */
  38   unsigned long next_start, next_end, curr_start, curr_end;
  39 #if STACK_DIRECTION < 0
  40   unsigned long prev_end;
  41 #endif
  42
  43   /* Open the current process' maps file.  It describes one VMA per line.
  44      There are two such files:
  45        - /proc/curproc/map in FreeBSD syntax,
  46        - /proc/curproc/maps in Linux syntax.
  47      Cf. <http://cvsweb.netbsd.org/bsdweb.cgi/src/sys/miscfs/procfs/procfs_map.c?rev=HEAD> */
  48   if (rof_open (&rof, "/proc/curproc/map") < 0)
  49     goto failed;
  50
  51 #if STACK_DIRECTION < 0
  52   prev_end = 0;
  53 #endif
  54   for (curr_start = curr_end = 0; ;)
  55     {
  56       if (!(rof_getchar (&rof) == '0'
  57             && rof_getchar (&rof) == 'x'
  58             && rof_scanf_lx (&rof, &next_start) >= 0))
  59         break;
  60       while (c = rof_peekchar (&rof), c == ' ' || c == '\t')
  61         rof_getchar (&rof);
  62       if (!(rof_getchar (&rof) == '0'
  63             && rof_getchar (&rof) == 'x'
  64             && rof_scanf_lx (&rof, &next_end) >= 0))
  65         break;
  66       while (c = rof_getchar (&rof), c != -1 && c != '\n')
  67         continue;
  68       if (next_start == curr_end)
  69         {
  70           /* Merge adjacent segments.  */
  71           curr_end = next_end;
  72         }
  73       else
  74         {
  75           if (curr_start < curr_end
  76               && address >= curr_start && address <= curr_end-1)
  77             goto found;
  78 #if STACK_DIRECTION < 0
  79           prev_end = curr_end;
  80 #endif
  81           curr_start = next_start; curr_end = next_end;
  82         }
  83     }
  84   if (address >= curr_start && address <= curr_end-1)
  85     found:
  86     {
  87       vma->start = curr_start;
  88       vma->end = curr_end;
  89 #if STACK_DIRECTION < 0
  90       vma->prev_end = prev_end;
  91 #else
  92       if (rof_getchar (&rof) == '0'
  93           && rof_getchar (&rof) == 'x'
  94           && rof_scanf_lx (&rof, &vma->next_start) >= 0)
  95         {
  96           while (c = rof_peekchar (&rof), c == ' ' || c == '\t')
  97             rof_getchar (&rof);
  98           if (rof_getchar (&rof) == '0'
  99               && rof_getchar (&rof) == 'x'
 100               && rof_scanf_lx (&rof, &next_end) >= 0)
 101             ;
 102           else
 103             vma->next_start = 0;
 104         }
 105       else
 106         vma->next_start = 0;
 107 #endif
 108       rof_close (&rof);
 109       vma->is_near_this = simple_is_near_this;
 110       return 0;
 111     }
 112   rof_close (&rof);
 113  failed:
 114 #if HAVE_MINCORE
 115   return mincore_get_vma (address, vma);
 116 #endif
 117   return -1;
 118 }