1 /* watch.c - watchpoint functions for malloc */
2
3 /* Copyright (C) 2001-2003 Free Software Foundation, Inc.
4
5 This file is part of GNU Bash, the Bourne Again SHell.
6
7 Bash is free software: you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation, either version 3 of the License, or
10 (at your option) any later version.
11
12 Bash is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with Bash. If not, see <http://www.gnu.org/licenses/>.
19 */
20
21 #ifdef HAVE_CONFIG_H
22 # include <config.h>
23 #endif
24
25 #include <stdio.h>
26
27 #include "imalloc.h"
28
29 #ifdef MALLOC_WATCH
30 #include "watch.h"
31
32 #define WATCH_MAX 32
33
34 int _malloc_nwatch;
35 static PTR_T _malloc_watch_list[WATCH_MAX];
36
37 static void
watch_warn(addr,file,line,type,data)38 watch_warn (addr, file, line, type, data)
39 PTR_T addr;
40 const char *file;
41 int line, type;
42 unsigned long data;
43 {
44 char *tag;
45
46 if (type == W_ALLOC)
47 tag = "allocated";
48 else if (type == W_FREE)
49 tag = "freed";
50 else if (type == W_REALLOC)
51 tag = "requesting resize";
52 else if (type == W_RESIZED)
53 tag = "just resized";
54 else
55 tag = "bug: unknown operation";
56
57 fprintf (stderr, "malloc: watch alert: %p %s ", addr, tag);
58 if (data != (unsigned long)-1)
59 fprintf (stderr, "(size %lu) ", data);
60 fprintf (stderr, "from '%s:%d'\n", file ? file : "unknown", line);
61 }
62
63 void
_malloc_ckwatch(addr,file,line,type,data)64 _malloc_ckwatch (addr, file, line, type, data)
65 PTR_T addr;
66 const char *file;
67 int line, type;
68 unsigned long data;
69 {
70 register int i;
71
72 for (i = _malloc_nwatch - 1; i >= 0; i--)
73 {
74 if (_malloc_watch_list[i] == addr)
75 {
76 watch_warn (addr, file, line, type, data);
77 return;
78 }
79 }
80 }
81 #endif /* MALLOC_WATCH */
82
83 PTR_T
malloc_watch(addr)84 malloc_watch (addr)
85 PTR_T addr;
86 {
87 register int i;
88 PTR_T ret;
89
90 if (addr == 0)
91 return addr;
92 ret = (PTR_T)0;
93
94 #ifdef MALLOC_WATCH
95 for (i = _malloc_nwatch - 1; i >= 0; i--)
96 {
97 if (_malloc_watch_list[i] == addr)
98 break;
99 }
100 if (i < 0)
101 {
102 if (_malloc_nwatch == WATCH_MAX) /* full, take out first */
103 {
104 ret = _malloc_watch_list[0];
105 _malloc_nwatch--;
106 for (i = 0; i < _malloc_nwatch; i++)
107 _malloc_watch_list[i] = _malloc_watch_list[i+1];
108 }
109 _malloc_watch_list[_malloc_nwatch++] = addr;
110 }
111 #endif
112
113 return ret;
114 }
115
116 /* Remove a watchpoint set on ADDR. If ADDR is NULL, remove all
117 watchpoints. Returns ADDR if everything went OK, NULL if ADDR was
118 not being watched. */
119 PTR_T
malloc_unwatch(addr)120 malloc_unwatch (addr)
121 PTR_T addr;
122 {
123 #ifdef MALLOC_WATCH
124 register int i;
125
126 if (addr == 0)
127 {
128 for (i = 0; i < _malloc_nwatch; i++)
129 _malloc_watch_list[i] = (PTR_T)0;
130 _malloc_nwatch = 0;
131 return ((PTR_T)0);
132 }
133 else
134 {
135 for (i = 0; i < _malloc_nwatch; i++)
136 {
137 if (_malloc_watch_list[i] == addr)
138 break;
139 }
140 if (i == _malloc_nwatch)
141 return ((PTR_T)0); /* not found */
142 /* shuffle everything from i+1 to end down 1 */
143 _malloc_nwatch--;
144 for ( ; i < _malloc_nwatch; i++)
145 _malloc_watch_list[i] = _malloc_watch_list[i+1];
146 return addr;
147 }
148 #else
149 return ((PTR_T)0);
150 #endif
151 }
152