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-rw-r--r--gnu/usr.bin/gdb/mmalloc/mmtrace.c166
1 files changed, 166 insertions, 0 deletions
diff --git a/gnu/usr.bin/gdb/mmalloc/mmtrace.c b/gnu/usr.bin/gdb/mmalloc/mmtrace.c
new file mode 100644
index 000000000000..73368a1b57aa
--- /dev/null
+++ b/gnu/usr.bin/gdb/mmalloc/mmtrace.c
@@ -0,0 +1,166 @@
+/* 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);
+}
+