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-rw-r--r--mmalloc/mmcheck.c223
1 files changed, 0 insertions, 223 deletions
diff --git a/mmalloc/mmcheck.c b/mmalloc/mmcheck.c
deleted file mode 100644
index 48936b3e630..00000000000
--- a/mmalloc/mmcheck.c
+++ /dev/null
@@ -1,223 +0,0 @@
-/* Standard debugging hooks for `mmalloc'.
- Copyright 1990, 1991, 1992 Free Software Foundation
-
- Written May 1989 by Mike Haertel.
- Heavily modified Mar 1992 by Fred Fish (fnf@cygnus.com)
-
-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., 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. */
-
-#include "mmprivate.h"
-
-/* Default function to call when something awful happens. The application
- can specify an alternate function to be called instead (and probably will
- want to). */
-
-extern void abort PARAMS ((void));
-
-/* Arbitrary magical numbers. */
-
-#define MAGICWORD (unsigned int) 0xfedabeeb /* Active chunk */
-#define MAGICWORDFREE (unsigned int) 0xdeadbeef /* Inactive chunk */
-#define MAGICBYTE ((char) 0xd7)
-
-/* Each memory allocation is bounded by a header structure and a trailer
- byte. I.E.
-
- <size><magicword><user's allocation><magicbyte>
-
- The pointer returned to the user points to the first byte in the
- user's allocation area. The magic word can be tested to detect
- buffer underruns and the magic byte can be tested to detect overruns. */
-
-struct hdr
- {
- size_t size; /* Exact size requested by user. */
- unsigned long int magic; /* Magic number to check header integrity. */
- };
-
-static void checkhdr PARAMS ((struct mdesc *, CONST struct hdr *));
-static void mfree_check PARAMS ((PTR, PTR));
-static PTR mmalloc_check PARAMS ((PTR, size_t));
-static PTR mrealloc_check PARAMS ((PTR, PTR, size_t));
-
-/* Check the magicword and magicbyte, and if either is corrupted then
- call the emergency abort function specified for the heap in use. */
-
-static void
-checkhdr (mdp, hdr)
- struct mdesc *mdp;
- CONST struct hdr *hdr;
-{
- if (hdr -> magic != MAGICWORD ||
- ((char *) &hdr[1])[hdr -> size] != MAGICBYTE)
- {
- (*mdp -> abortfunc)();
- }
-}
-
-static void
-mfree_check (md, ptr)
- PTR md;
- PTR ptr;
-{
- struct hdr *hdr = ((struct hdr *) ptr) - 1;
- struct mdesc *mdp;
-
- mdp = MD_TO_MDP (md);
- checkhdr (mdp, hdr);
- hdr -> magic = MAGICWORDFREE;
- mdp -> mfree_hook = NULL;
- mfree (md, (PTR)hdr);
- mdp -> mfree_hook = mfree_check;
-}
-
-static PTR
-mmalloc_check (md, size)
- PTR md;
- size_t size;
-{
- struct hdr *hdr;
- struct mdesc *mdp;
- size_t nbytes;
-
- mdp = MD_TO_MDP (md);
- mdp -> mmalloc_hook = NULL;
- nbytes = sizeof (struct hdr) + size + 1;
- hdr = (struct hdr *) mmalloc (md, nbytes);
- mdp -> mmalloc_hook = mmalloc_check;
- if (hdr != NULL)
- {
- hdr -> size = size;
- hdr -> magic = MAGICWORD;
- hdr++;
- *((char *) hdr + size) = MAGICBYTE;
- }
- return ((PTR) hdr);
-}
-
-static PTR
-mrealloc_check (md, ptr, size)
- PTR md;
- PTR ptr;
- size_t size;
-{
- struct hdr *hdr = ((struct hdr *) ptr) - 1;
- struct mdesc *mdp;
- size_t nbytes;
-
- mdp = MD_TO_MDP (md);
- checkhdr (mdp, hdr);
- mdp -> mfree_hook = NULL;
- mdp -> mmalloc_hook = NULL;
- mdp -> mrealloc_hook = NULL;
- nbytes = sizeof (struct hdr) + size + 1;
- hdr = (struct hdr *) mrealloc (md, (PTR) hdr, nbytes);
- mdp -> mfree_hook = mfree_check;
- mdp -> mmalloc_hook = mmalloc_check;
- mdp -> mrealloc_hook = mrealloc_check;
- if (hdr != NULL)
- {
- hdr -> size = size;
- hdr++;
- *((char *) hdr + size) = MAGICBYTE;
- }
- return ((PTR) hdr);
-}
-
-/* Turn on default checking for mmalloc/mrealloc/mfree, for the heap specified
- by MD. If FUNC is non-NULL, it is a pointer to the function to call
- to abort whenever memory corruption is detected. By default, this is the
- standard library function abort().
-
- Note that we disallow installation of initial checking hooks if mmalloc
- has been called at any time for this particular heap, since if any region
- that is allocated prior to installation of the hooks is subsequently
- reallocated or freed after installation of the hooks, it is guaranteed
- to trigger a memory corruption error. We do this by checking the state
- of the MMALLOC_INITIALIZED flag. If the FORCE argument is non-zero, this
- checking is disabled and it is allowed to install the checking hooks at any
- time. This is useful on systems where the C runtime makes one or more
- malloc calls before the user code had a chance to call mmcheck or mmcheckf,
- but never calls free with these values. Thus if we are certain that only
- values obtained from mallocs after an mmcheck/mmcheckf will ever be passed
- to free(), we can go ahead and force installation of the useful checking
- hooks.
-
- However, we can call this function at any time after the initial call,
- to update the function pointers to the checking routines and to the
- user defined corruption handler routine, as long as these function pointers
- have been previously extablished by the initial call. Note that we
- do this automatically when remapping a previously used heap, to ensure
- that the hooks get updated to the correct values, although the corruption
- handler pointer gets set back to the default. The application can then
- call mmcheck to use a different corruption handler if desired.
-
- Returns non-zero if checking is successfully enabled, zero otherwise. */
-
-int
-mmcheckf (md, func, force)
- PTR md;
- void (*func) PARAMS ((void));
- int force;
-{
- struct mdesc *mdp;
- int rtnval;
-
- mdp = MD_TO_MDP (md);
-
- /* We can safely set or update the abort function at any time, regardless
- of whether or not we successfully do anything else. */
-
- mdp -> abortfunc = (func != NULL ? func : abort);
-
- /* If we haven't yet called mmalloc the first time for this heap, or if we
- have hooks that were previously installed, then allow the hooks to be
- initialized or updated. */
-
- if (force ||
- !(mdp -> flags & MMALLOC_INITIALIZED) ||
- (mdp -> mfree_hook != NULL))
- {
- mdp -> mfree_hook = mfree_check;
- mdp -> mmalloc_hook = mmalloc_check;
- mdp -> mrealloc_hook = mrealloc_check;
- mdp -> flags |= MMALLOC_MMCHECK_USED;
- rtnval = 1;
- }
- else
- {
- rtnval = 0;
- }
-
- return (rtnval);
-}
-
-/* This routine is for backwards compatibility only, in case there are
- still callers to the original mmcheck function. */
-
-int
-mmcheck (md, func)
- PTR md;
- void (*func) PARAMS ((void));
-{
- int rtnval;
-
- rtnval = mmcheckf (md, func, 0);
- return (rtnval);
-}
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