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
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
|
/* More debugging hooks for `malloc'.
Copyright (C) 1991, 92, 93, 94, 96, 97 Free Software Foundation, Inc.
Written April 2, 1991 by John Gilmore of Cygnus Support.
Based on mcheck.c by Mike Haertel.
This 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.
This 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 this 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.
The author may be reached (Email) at the address mike@ai.mit.edu,
or (US mail) as Mike Haertel c/o Free Software Foundation. */
#ifndef _MALLOC_INTERNAL
#define _MALLOC_INTERNAL
#include <malloc.h>
#include <mcheck.h>
#include <bits/libc-lock.h>
#endif
#ifdef HAVE_ELF
#include <link.h>
#endif
#include <stdio.h>
#ifndef __GNU_LIBRARY__
extern char *getenv ();
#else
#include <stdlib.h>
#endif
static FILE *mallstream;
static char mallenv[]= "MALLOC_TRACE";
static char mallbuf[BUFSIZ]; /* Buffer for the output. */
__libc_lock_define_initialized (static, lock);
/* Address to breakpoint on accesses to... */
__ptr_t mallwatch;
/* File name and line number information, for callers that had
the foresight to call through a macro. */
char *_mtrace_file;
int _mtrace_line;
/* Old hook values. */
static void (*tr_old_free_hook) __P ((__ptr_t ptr, const __ptr_t));
static __ptr_t (*tr_old_malloc_hook) __P ((__malloc_size_t size,
const __ptr_t));
static __ptr_t (*tr_old_realloc_hook) __P ((__ptr_t ptr,
__malloc_size_t size,
const __ptr_t));
/* This function is called when the block being alloc'd, realloc'd, or
freed has an address matching the variable "mallwatch". In a debugger,
set "mallwatch" to the address of interest, then put a breakpoint on
tr_break. */
void tr_break __P ((void));
void
tr_break ()
{
}
static void tr_where __P ((const __ptr_t));
static void
tr_where (caller)
const __ptr_t caller;
{
if (_mtrace_file)
{
fprintf (mallstream, "@ %s:%d ", _mtrace_file, _mtrace_line);
_mtrace_file = NULL;
}
else if (caller != NULL)
{
#ifdef HAVE_ELF
Dl_info info;
if (_dl_addr (caller, &info))
{
fprintf (mallstream, "@ %s%s%s%s%s[%p]",
info.dli_fname ?: "", info.dli_fname ? ":" : "",
info.dli_sname ? "(" : "",
info.dli_sname ?: "", info.dli_sname ? ") " : " ",
caller);
}
else
#endif
fprintf (mallstream, "@ [%p] ", caller);
}
}
static void tr_freehook __P ((__ptr_t, const __ptr_t));
static void
tr_freehook (ptr, caller)
__ptr_t ptr;
const __ptr_t caller;
{
tr_where (caller);
/* Be sure to print it first. */
fprintf (mallstream, "- %p\n", ptr);
if (ptr == mallwatch)
tr_break ();
__libc_lock_lock (lock);
__free_hook = tr_old_free_hook;
if (tr_old_free_hook != NULL)
(*tr_old_free_hook) (ptr, caller);
else
free (ptr);
__free_hook = tr_freehook;
__libc_lock_unlock (lock);
}
static __ptr_t tr_mallochook __P ((__malloc_size_t, const __ptr_t));
static __ptr_t
tr_mallochook (size, caller)
__malloc_size_t size;
const __ptr_t caller;
{
__ptr_t hdr;
__libc_lock_lock (lock);
__malloc_hook = tr_old_malloc_hook;
if (tr_old_malloc_hook != NULL)
hdr = (__ptr_t) (*tr_old_malloc_hook) (size, caller);
else
hdr = (__ptr_t) malloc (size);
__malloc_hook = tr_mallochook;
__libc_lock_unlock (lock);
tr_where (caller);
/* We could be printing a NULL here; that's OK. */
fprintf (mallstream, "+ %p %#lx\n", hdr, (unsigned long)size);
if (hdr == mallwatch)
tr_break ();
return hdr;
}
static __ptr_t tr_reallochook __P ((__ptr_t, __malloc_size_t, const __ptr_t));
static __ptr_t
tr_reallochook (ptr, size, caller)
__ptr_t ptr;
__malloc_size_t size;
const __ptr_t caller;
{
__ptr_t hdr;
if (ptr == mallwatch)
tr_break ();
__libc_lock_lock (lock);
__free_hook = tr_old_free_hook;
__malloc_hook = tr_old_malloc_hook;
__realloc_hook = tr_old_realloc_hook;
if (tr_old_realloc_hook != NULL)
hdr = (__ptr_t) (*tr_old_realloc_hook) (ptr, size, caller);
else
hdr = (__ptr_t) realloc (ptr, size);
__free_hook = tr_freehook;
__malloc_hook = tr_mallochook;
__realloc_hook = tr_reallochook;
__libc_lock_unlock (lock);
tr_where (caller);
if (hdr == NULL)
/* Failed realloc. */
fprintf (mallstream, "! %p %#lx\n", ptr, (unsigned long)size);
else if (ptr == NULL)
fprintf (mallstream, "+ %p %#lx\n", hdr, (unsigned long)size);
else
fprintf (mallstream, "< %p\n> %p %#lx\n", ptr, hdr, (unsigned long)size);
if (hdr == mallwatch)
tr_break ();
return hdr;
}
/* We enable tracing if either the environment variable MALLOC_TRACE
is set, or if the variable mallwatch has been patched to an address
that the debugging user wants us to stop on. When patching mallwatch,
don't forget to set a breakpoint on tr_break! */
void
mtrace ()
{
char *mallfile;
/* Don't panic if we're called more than once. */
if (mallstream != NULL)
return;
#ifdef _LIBC
/* When compiling the GNU libc we use the secure getenv function
which prevents the misuse in case of SUID or SGID enabled
programs. */
mallfile = __secure_getenv (mallenv);
#else
mallfile = getenv (mallenv);
#endif
if (mallfile != NULL || mallwatch != NULL)
{
mallstream = fopen (mallfile != NULL ? mallfile : "/dev/null", "w");
if (mallstream != NULL)
{
/* Be sure it doesn't malloc its buffer! */
setbuf (mallstream, mallbuf);
fprintf (mallstream, "= Start\n");
tr_old_free_hook = __free_hook;
__free_hook = tr_freehook;
tr_old_malloc_hook = __malloc_hook;
__malloc_hook = tr_mallochook;
tr_old_realloc_hook = __realloc_hook;
__realloc_hook = tr_reallochook;
}
}
}
void
muntrace ()
{
if (mallstream == NULL)
return;
fprintf (mallstream, "= End\n");
fclose (mallstream);
mallstream = NULL;
__free_hook = tr_old_free_hook;
__malloc_hook = tr_old_malloc_hook;
__realloc_hook = tr_old_realloc_hook;
}
|
