summaryrefslogtreecommitdiffstats
path: root/lib/malloc/watch.c
blob: 00c8a8248b4e9bc317be38115439f0dc911d85cc (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
/* watch.c - watchpoint functions for malloc */

/* Copyright (C) 2001-2003 Free Software Foundation, Inc.

   This file is part of GNU Bash, the Bourne Again SHell.

   Bash 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 3 of the License, or
   (at your option) any later version.

   Bash 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 Bash.  If not, see <http://www.gnu.org/licenses/>.
*/

#ifdef HAVE_CONFIG_H
#  include <config.h>
#endif

#include <stdio.h>

#include "imalloc.h"

#ifdef MALLOC_WATCH
#include "watch.h"

#define WATCH_MAX	32

int		_malloc_nwatch;
static PTR_T	_malloc_watch_list[WATCH_MAX];

static void
watch_warn (addr, file, line, type, data)
     PTR_T addr;
     const char *file;
     int line, type;
     unsigned long data;
{
  char *tag;

  if (type == W_ALLOC)
    tag = "allocated";
  else if (type == W_FREE)
    tag = "freed";
  else if (type == W_REALLOC)
    tag = "requesting resize";
  else if (type == W_RESIZED)
    tag = "just resized";
  else
    tag = "bug: unknown operation";

  fprintf (stderr, "malloc: watch alert: %p %s ", addr, tag);
  if (data != (unsigned long)-1)
    fprintf (stderr, "(size %lu) ", data);
  fprintf (stderr, "from '%s:%d'\n", file ? file : "unknown", line);
}

void
_malloc_ckwatch (addr, file, line, type, data)
     PTR_T addr;
     const char *file;
     int line, type;
     unsigned long data;
{
  register int i;

  for (i = _malloc_nwatch - 1; i >= 0; i--)
    {
      if (_malloc_watch_list[i] == addr)
	{
	  watch_warn (addr, file, line, type, data);
	  return;
	}
    }
}
#endif /* MALLOC_WATCH */

PTR_T
malloc_watch (addr)
     PTR_T addr;
{
  register int i;
  PTR_T ret;

  if (addr == 0)
    return addr;
  ret = (PTR_T)0;

#ifdef MALLOC_WATCH
  for (i = _malloc_nwatch - 1; i >= 0; i--)
    {
      if (_malloc_watch_list[i] == addr)
        break;
    }
  if (i < 0)
    {
      if (_malloc_nwatch == WATCH_MAX)	/* full, take out first */
	{
	  ret = _malloc_watch_list[0];
	  _malloc_nwatch--;
	  for (i = 0; i < _malloc_nwatch; i++)
	    _malloc_watch_list[i] = _malloc_watch_list[i+1];
	}
      _malloc_watch_list[_malloc_nwatch++] = addr;
    }
#endif

  return ret;  
}

/* Remove a watchpoint set on ADDR.  If ADDR is NULL, remove all
   watchpoints.  Returns ADDR if everything went OK, NULL if ADDR was
   not being watched. */
PTR_T
malloc_unwatch (addr)
     PTR_T addr;
{
#ifdef MALLOC_WATCH
  register int i;

  if (addr == 0)
    {
      for (i = 0; i < _malloc_nwatch; i++)
        _malloc_watch_list[i] = (PTR_T)0;
      _malloc_nwatch = 0;
      return ((PTR_T)0);
    }
  else
    {
      for (i = 0; i < _malloc_nwatch; i++)
	{
	  if (_malloc_watch_list[i] == addr)
	    break;
	}
      if (i == _malloc_nwatch)
        return ((PTR_T)0);		/* not found */
      /* shuffle everything from i+1 to end down 1 */
      _malloc_nwatch--;
      for ( ; i < _malloc_nwatch; i++)
        _malloc_watch_list[i] = _malloc_watch_list[i+1];
      return addr;
    }
#else
  return ((PTR_T)0);
#endif
}