1 /* More debugging hooks for `malloc'.
2 Copyright (C) 1991, 1992 Free Software Foundation, Inc.
3 Written April 2, 1991 by John Gilmore of Cygnus Support.
4 Based on mcheck.c by Mike Haertel.
6 This library is free software; you can redistribute it and/or
7 modify it under the terms of the GNU Library General Public License as
8 published by the Free Software Foundation; either version 2 of the
9 License, or (at your option) any later version.
11 This library is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 Library General Public License for more details.
16 You should have received a copy of the GNU Library General Public
17 License along with this library; see the file COPYING.LIB. If
18 not, write to the Free Software Foundation, Inc., 675 Mass Ave,
19 Cambridge, MA 02139, USA.
21 The author may be reached (Email) at the address mike@ai.mit.edu,
22 or (US mail) as Mike Haertel c/o Free Software Foundation. */
26 #ifndef _MALLOC_INTERNAL
27 #define _MALLOC_INTERNAL
33 #ifndef __GNU_LIBRARY__
34 extern char *getenv ();
39 static FILE *mallstream;
40 static char mallenv[]= "MALLOC_TRACE";
41 static char mallbuf[BUFSIZ]; /* Buffer for the output. */
43 /* Address to breakpoint on accesses to... */
46 /* Old hook values. */
47 static void (*tr_old_free_hook) __P ((__ptr_t ptr));
48 static __ptr_t (*tr_old_malloc_hook) __P ((size_t size));
49 static __ptr_t (*tr_old_realloc_hook) __P ((__ptr_t ptr, size_t size));
52 * Added by TYT, 10/10/93 --- so that we can print
54 FILE *malloc_get_mallstream()
59 /* This function is called when the block being alloc'd, realloc'd, or
60 freed has an address matching the variable "mallwatch". In a debugger,
61 set "mallwatch" to the address of interest, then put a breakpoint on
64 void tr_break __P ((void));
70 static void tr_freehook __P ((__ptr_t));
75 fprintf (mallstream, "- %p\n", ptr); /* Be sure to print it first. */
78 __free_hook = tr_old_free_hook;
80 __free_hook = tr_freehook;
83 static __ptr_t tr_mallochook __P ((size_t));
90 __malloc_hook = tr_old_malloc_hook;
91 hdr = (__ptr_t) malloc (size);
92 __malloc_hook = tr_mallochook;
94 /* We could be printing a NULL here; that's OK. */
95 fprintf (mallstream, "+ %p %d\n", hdr, size);
103 static __ptr_t tr_reallochook __P ((__ptr_t, size_t));
105 tr_reallochook (ptr, size)
111 if (ptr == mallwatch)
114 __free_hook = tr_old_free_hook;
115 __malloc_hook = tr_old_malloc_hook;
116 __realloc_hook = tr_old_realloc_hook;
117 hdr = (__ptr_t) realloc (ptr, size);
118 __free_hook = tr_freehook;
119 __malloc_hook = tr_mallochook;
120 __realloc_hook = tr_reallochook;
122 /* Failed realloc. */
123 fprintf (mallstream, "! %p %d\n", ptr, size);
125 fprintf (mallstream, "< %p\n> %p %d\n", ptr, hdr, size);
127 if (hdr == mallwatch)
133 /* We enable tracing if either the environment variable MALLOC_TRACE
134 is set, or if the variable mallwatch has been patched to an address
135 that the debugging user wants us to stop on. When patching mallwatch,
136 don't forget to set a breakpoint on tr_break! */
143 mallfile = getenv (mallenv);
144 if (mallfile != NULL || mallwatch != NULL)
146 mallstream = fopen (mallfile != NULL ? mallfile : "/dev/null", "w");
147 if (mallstream != NULL)
149 /* Be sure it doesn't malloc its buffer! */
150 setbuf (mallstream, mallbuf);
151 fprintf (mallstream, "= Start\n");
152 tr_old_free_hook = __free_hook;
153 __free_hook = tr_freehook;
154 tr_old_malloc_hook = __malloc_hook;
155 __malloc_hook = tr_mallochook;
156 tr_old_realloc_hook = __realloc_hook;
157 __realloc_hook = tr_reallochook;