freebsd-dev/gnu/usr.bin/gdb/mmalloc/mmtrace.c
Paul Richards ea8c7ac7d0 GDB-4.12 from ports with support for shlibs but not the kernel.
This is a greatly pared down version of the full gdb-4.12, all the
config stuff has been removed and the supporting libraries have
been stripped to a minimum. This is a 1.1.5 only port, I'll do a
more complete port for 2.0 which will have all the config stuff
and will install the gnu support libraries as system libraries like
we do for readline.

There wasn't much point for 1.1.5 since only gdb would use them so I
went for saving space instead. For 2.0 I'll config all the
other gnu tools to use them as well.
1994-06-10 13:42:18 +00:00

167 lines
4.3 KiB
C

/* More debugging hooks for `mmalloc'.
Copyright 1991, 1992 Free Software Foundation
Written April 2, 1991 by John Gilmore of Cygnus Support
Based on mcheck.c by Mike Haertel.
Modified Mar 1992 by Fred Fish. (fnf@cygnus.com)
This file is part of the GNU C Library.
The GNU C 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.
The GNU C 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 the GNU C Library; see the file COPYING.LIB. If
not, write to the Free Software Foundation, Inc., 675 Mass Ave,
Cambridge, MA 02139, USA. */
#include <stdio.h>
#include "mmalloc.h"
#ifndef __GNU_LIBRARY__
extern char *getenv ();
#endif
static FILE *mallstream;
#if 0 /* FIXME: Disabled for now. */
static char mallenv[] = "MALLOC_TRACE";
static char mallbuf[BUFSIZ]; /* Buffer for the output. */
#endif
/* Address to breakpoint on accesses to... */
static PTR mallwatch;
/* Old hook values. */
static void (*old_mfree_hook) PARAMS ((PTR, PTR));
static PTR (*old_mmalloc_hook) PARAMS ((PTR, size_t));
static PTR (*old_mrealloc_hook) PARAMS ((PTR, PTR, size_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. */
static void
tr_break ()
{
}
static void
tr_freehook (md, ptr)
PTR md;
PTR ptr;
{
struct mdesc *mdp;
mdp = MD_TO_MDP (md);
/* Be sure to print it first. */
fprintf (mallstream, "- %08x\n", (unsigned int) ptr);
if (ptr == mallwatch)
tr_break ();
mdp -> mfree_hook = old_mfree_hook;
mfree (md, ptr);
mdp -> mfree_hook = tr_freehook;
}
static PTR
tr_mallochook (md, size)
PTR md;
size_t size;
{
PTR hdr;
struct mdesc *mdp;
mdp = MD_TO_MDP (md);
mdp -> mmalloc_hook = old_mmalloc_hook;
hdr = (PTR) mmalloc (md, size);
mdp -> mmalloc_hook = tr_mallochook;
/* We could be printing a NULL here; that's OK. */
fprintf (mallstream, "+ %08x %x\n", (unsigned int) hdr, size);
if (hdr == mallwatch)
tr_break ();
return (hdr);
}
static PTR
tr_reallochook (md, ptr, size)
PTR md;
PTR ptr;
size_t size;
{
PTR hdr;
struct mdesc *mdp;
mdp = MD_TO_MDP (md);
if (ptr == mallwatch)
tr_break ();
mdp -> mfree_hook = old_mfree_hook;
mdp -> mmalloc_hook = old_mmalloc_hook;
mdp -> mrealloc_hook = old_mrealloc_hook;
hdr = (PTR) mrealloc (md, ptr, size);
mdp -> mfree_hook = tr_freehook;
mdp -> mmalloc_hook = tr_mallochook;
mdp -> mrealloc_hook = tr_reallochook;
if (hdr == NULL)
/* Failed realloc. */
fprintf (mallstream, "! %08x %x\n", (unsigned int) ptr, size);
else
fprintf (mallstream, "< %08x\n> %08x %x\n", (unsigned int) ptr,
(unsigned int) hdr, 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! */
int
mmtrace ()
{
#if 0 /* FIXME! This is disabled for now until we figure out how to
maintain a stack of hooks per heap, since we might have other
hooks (such as set by mmcheck) active also. */
char *mallfile;
mallfile = getenv (mallenv);
if (mallfile != NULL || mallwatch != NULL)
{
mallstream = fopen (mallfile != NULL ? mallfile : "/dev/null", "w");
if (mallstream != NULL)
{
/* Be sure it doesn't mmalloc its buffer! */
setbuf (mallstream, mallbuf);
fprintf (mallstream, "= Start\n");
old_mfree_hook = mdp -> mfree_hook;
mdp -> mfree_hook = tr_freehook;
old_mmalloc_hook = mdp -> mmalloc_hook;
mdp -> mmalloc_hook = tr_mallochook;
old_mrealloc_hook = mdp -> mrealloc_hook;
mdp -> mrealloc_hook = tr_reallochook;
}
}
#endif /* 0 */
return (1);
}