[thirdparty/glibc.git] / malloc / mcheck.c

/* Standard debugging hooks for `malloc'.
   Copyright (C) 1990-1997, 1999, 2000, 2001 Free Software Foundation, Inc.
   Written May 1989 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 <stdint.h>
# include <stdio.h>
# include <libintl.h>
#endif

/* Old hook values.  */
static void (*old_free_hook) __P ((__ptr_t ptr, __const __ptr_t));
static __ptr_t (*old_malloc_hook) __P ((__malloc_size_t size, const __ptr_t));
static __ptr_t (*old_realloc_hook) __P ((__ptr_t ptr, __malloc_size_t size,
					 __const __ptr_t));

/* Function to call when something awful happens.  */
static void (*abortfunc) __P ((enum mcheck_status));

/* Arbitrary magical numbers.  */
#define MAGICWORD	0xfedabeeb
#define MAGICFREE	0xd8675309
#define MAGICBYTE	((char) 0xd7)
#define MALLOCFLOOD	((char) 0x93)
#define FREEFLOOD	((char) 0x95)

struct hdr
  {
    __malloc_size_t size;	/* Exact size requested by user.  */
    unsigned long int magic;	/* Magic number to check header integrity.  */
    struct hdr *prev;
    struct hdr *next;
  };

/* This is the beginning of the list of all memory blocks allocated.
   It is only constructed if the pedantic testing is requested.  */
static struct hdr *root;

/* Nonzero if pedentic checking of all blocks is requested.  */
static int pedantic;

#if defined _LIBC || defined STDC_HEADERS || defined USG
# include <string.h>
# define flood memset
#else
static void flood __P ((__ptr_t, int, __malloc_size_t));
static void
flood (ptr, val, size)
     __ptr_t ptr;
     int val;
     __malloc_size_t size;
{
  char *cp = ptr;
  while (size--)
    *cp++ = val;
}
#endif

static enum mcheck_status checkhdr __P ((const struct hdr *));
static enum mcheck_status
checkhdr (hdr)
     const struct hdr *hdr;
{
  enum mcheck_status status;
  switch (hdr->magic ^ ((uintptr_t) hdr->prev + (uintptr_t) hdr->next))
    {
    default:
      status = MCHECK_HEAD;
      break;
    case MAGICFREE:
      status = MCHECK_FREE;
      break;
    case MAGICWORD:
      if (((char *) &hdr[1])[hdr->size] != MAGICBYTE)
	status = MCHECK_TAIL;
      else
	status = MCHECK_OK;
      break;
    }
  if (status != MCHECK_OK)
    (*abortfunc) (status);
  return status;
}

void
mcheck_check_all ()
{
  /* Walk through all the active blocks and test whether they were tempered
     with.  */
  struct hdr *runp = root;

  /* Temporarily turn off the checks.  */
  pedantic = 0;

  while (runp != NULL)
    {
      (void) checkhdr (runp);

      runp = runp->next;
    }

  /* Turn checks on again.  */
  pedantic = 1;
}

static void unlink_blk __P ((struct hdr *ptr));
static void
unlink_blk (ptr)
     struct hdr *ptr;
{
  if (ptr->next != NULL)
    {
      ptr->next->prev = ptr->prev;
      ptr->next->magic = MAGICWORD ^ ((uintptr_t) ptr->next->prev
				      + (uintptr_t) ptr->next->next);
    }
  if (ptr->prev != NULL)
    {
      ptr->prev->next = ptr->next;
      ptr->prev->magic = MAGICWORD ^ ((uintptr_t) ptr->prev->prev
				      + (uintptr_t) ptr->prev->next);
    }
  else
    root = ptr->next;
}

static void link_blk  __P ((struct hdr *ptr));
static void
link_blk (hdr)
     struct hdr *hdr;
{
  hdr->prev = NULL;
  hdr->next = root;
  root = hdr;
  hdr->magic = MAGICWORD ^ (uintptr_t) hdr->next;

  /* And the next block.  */
  if (hdr->next != NULL)
    {
      hdr->next->prev = hdr;
      hdr->next->magic = MAGICWORD ^ ((uintptr_t) hdr
				      + (uintptr_t) hdr->next->next);
    }
}

static void freehook __P ((__ptr_t, const __ptr_t));
static void
freehook (ptr, caller)
     __ptr_t ptr;
     const __ptr_t caller;
{
  if (pedantic)
    mcheck_check_all ();
  if (ptr)
    {
      struct hdr *hdr = ((struct hdr *) ptr) - 1;
      checkhdr (hdr);
      hdr->magic = MAGICFREE;
      unlink_blk (hdr);
      hdr->prev = hdr->next = NULL;
      flood (ptr, FREEFLOOD, hdr->size);
      ptr = (__ptr_t) hdr;
    }
  __free_hook = old_free_hook;
  if (old_free_hook != NULL)
    (*old_free_hook) (ptr, caller);
  else
    free (ptr);
  __free_hook = freehook;
}

static __ptr_t mallochook __P ((__malloc_size_t, const __ptr_t));
static __ptr_t
mallochook (size, caller)
     __malloc_size_t size;
     const __ptr_t caller;
{
  struct hdr *hdr;

  if (pedantic)
    mcheck_check_all ();

  __malloc_hook = old_malloc_hook;
  if (old_malloc_hook != NULL)
    hdr = (struct hdr *) (*old_malloc_hook) (sizeof (struct hdr) + size + 1,
					     caller);
  else
    hdr = (struct hdr *) malloc (sizeof (struct hdr) + size + 1);
  __malloc_hook = mallochook;
  if (hdr == NULL)
    return NULL;

  hdr->size = size;
  link_blk (hdr);
  ((char *) &hdr[1])[size] = MAGICBYTE;
  flood ((__ptr_t) (hdr + 1), MALLOCFLOOD, size);
  return (__ptr_t) (hdr + 1);
}

static __ptr_t reallochook __P ((__ptr_t, __malloc_size_t, const __ptr_t));
static __ptr_t
reallochook (ptr, size, caller)
     __ptr_t ptr;
     __malloc_size_t size;
     const __ptr_t caller;
{
  struct hdr *hdr;
  __malloc_size_t osize;

  if (pedantic)
    mcheck_check_all ();

  if (ptr)
    {
      hdr = ((struct hdr *) ptr) - 1;
      osize = hdr->size;

      checkhdr (hdr);
      unlink_blk (hdr);
      if (size < osize)
	flood ((char *) ptr + size, FREEFLOOD, osize - size);
    }
  else
    {
      osize = 0;
      hdr = NULL;
    }
  __free_hook = old_free_hook;
  __malloc_hook = old_malloc_hook;
  __realloc_hook = old_realloc_hook;
  if (old_realloc_hook != NULL)
    hdr = (struct hdr *) (*old_realloc_hook) ((__ptr_t) hdr,
					      sizeof (struct hdr) + size + 1,
					      caller);
  else
    hdr = (struct hdr *) realloc ((__ptr_t) hdr,
				  sizeof (struct hdr) + size + 1);
  __free_hook = freehook;
  __malloc_hook = mallochook;
  __realloc_hook = reallochook;
  if (hdr == NULL)
    return NULL;

  hdr->size = size;
  link_blk (hdr);
  ((char *) &hdr[1])[size] = MAGICBYTE;
  if (size > osize)
    flood ((char *) (hdr + 1) + osize, MALLOCFLOOD, size - osize);
  return (__ptr_t) (hdr + 1);
}

static void mabort __P ((enum mcheck_status status))
     __attribute__ ((noreturn));
static void
mabort (status)
     enum mcheck_status status;
{
  const char *msg;
  switch (status)
    {
    case MCHECK_OK:
      msg = _("memory is consistent, library is buggy\n");
      break;
    case MCHECK_HEAD:
      msg = _("memory clobbered before allocated block\n");
      break;
    case MCHECK_TAIL:
      msg = _("memory clobbered past end of allocated block\n");
      break;
    case MCHECK_FREE:
      msg = _("block freed twice\n");
      break;
    default:
      msg = _("bogus mcheck_status, library is buggy\n");
      break;
    }
#ifdef _LIBC
  __libc_fatal (msg);
#else
  fprintf (stderr, "mcheck: %s", msg);
  fflush (stderr);
  abort ();
#endif
}

static int mcheck_used;

int
mcheck (func)
     void (*func) __P ((enum mcheck_status));
{
  abortfunc = (func != NULL) ? func : &mabort;

  /* These hooks may not be safely inserted if malloc is already in use.  */
  if (__malloc_initialized <= 0 && !mcheck_used)
    {
      old_free_hook = __free_hook;
      __free_hook = freehook;
      old_malloc_hook = __malloc_hook;
      __malloc_hook = mallochook;
      old_realloc_hook = __realloc_hook;
      __realloc_hook = reallochook;
      mcheck_used = 1;
    }

  return mcheck_used ? 0 : -1;
}

int
mcheck_pedantic (func)
      void (*func) __P ((enum mcheck_status));
{
  int res = mcheck (func);
  if (res == 0)
    pedantic = 1;
  return res;
}

enum mcheck_status
mprobe (__ptr_t ptr)
{
  return mcheck_used ? checkhdr (((struct hdr *) ptr) - 1) : MCHECK_DISABLED;
}
Commit	Line	Data
6d52618b	1	/* Standard debugging hooks for `malloc'.
159a2e1a	2	Copyright (C) 1990-1997, 1999, 2000, 2001 Free Software Foundation, Inc.
6d52618b UD	3	Written May 1989 by Mike Haertel.
	4
	5	This library is free software; you can redistribute it and/or
	6	modify it under the terms of the GNU Library General Public License as
	7	published by the Free Software Foundation; either version 2 of the
	8	License, or (at your option) any later version.
	9
	10	This library is distributed in the hope that it will be useful,
	11	but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	13	Library General Public License for more details.
	14
	15	You should have received a copy of the GNU Library General Public
	16	License along with this library; see the file COPYING.LIB. If not,
	17	write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
	18	Boston, MA 02111-1307, USA.
	19
	20	The author may be reached (Email) at the address mike@ai.mit.edu,
	21	or (US mail) as Mike Haertel c/o Free Software Foundation. */
	22
	23	#ifndef _MALLOC_INTERNAL
9756dfe1 UD	24	# define _MALLOC_INTERNAL
	25	# include <malloc.h>
	26	# include <mcheck.h>
8e605e78	27	# include <stdint.h>
9756dfe1	28	# include <stdio.h>
4360eafd	29	# include <libintl.h>
6d52618b UD	30	#endif
	31
	32	/* Old hook values. */
a2b08ee5 UD	33	static void (*old_free_hook) __P ((__ptr_t ptr, __const __ptr_t));
	34	static __ptr_t (*old_malloc_hook) __P ((__malloc_size_t size, const __ptr_t));
	35	static __ptr_t (*old_realloc_hook) __P ((__ptr_t ptr, __malloc_size_t size,
	36	__const __ptr_t));
6d52618b UD	37
	38	/* Function to call when something awful happens. */
	39	static void (*abortfunc) __P ((enum mcheck_status));
	40
	41	/* Arbitrary magical numbers. */
	42	#define MAGICWORD 0xfedabeeb
	43	#define MAGICFREE 0xd8675309
	44	#define MAGICBYTE ((char) 0xd7)
	45	#define MALLOCFLOOD ((char) 0x93)
	46	#define FREEFLOOD ((char) 0x95)
	47
	48	struct hdr
	49	{
8e605e78	50	__malloc_size_t size; /* Exact size requested by user. */
6d52618b	51	unsigned long int magic; /* Magic number to check header integrity. */
8e605e78 UD	52	struct hdr *prev;
8e605e78 UD	53	struct hdr *next;
6d52618b UD	54	};
6d52618b UD	55
8e605e78 UD	56	/* This is the beginning of the list of all memory blocks allocated.
	57	It is only constructed if the pedantic testing is requested. */
	58	static struct hdr *root;
	59
	60	/* Nonzero if pedentic checking of all blocks is requested. */
	61	static int pedantic;
	62
9756dfe1 UD	63	#if defined _LIBC \|\| defined STDC_HEADERS \|\| defined USG
	64	# include <string.h>
	65	# define flood memset
6d52618b UD	66	#else
	67	static void flood __P ((__ptr_t, int, __malloc_size_t));
	68	static void
	69	flood (ptr, val, size)
	70	__ptr_t ptr;
	71	int val;
	72	__malloc_size_t size;
	73	{
	74	char *cp = ptr;
	75	while (size--)
	76	*cp++ = val;
	77	}
	78	#endif
	79
	80	static enum mcheck_status checkhdr __P ((const struct hdr *));
	81	static enum mcheck_status
	82	checkhdr (hdr)
	83	const struct hdr *hdr;
	84	{
	85	enum mcheck_status status;
8e605e78	86	switch (hdr->magic ^ ((uintptr_t) hdr->prev + (uintptr_t) hdr->next))
6d52618b UD	87	{
	88	default:
	89	status = MCHECK_HEAD;
	90	break;
	91	case MAGICFREE:
	92	status = MCHECK_FREE;
	93	break;
	94	case MAGICWORD:
	95	if (((char *) &hdr[1])[hdr->size] != MAGICBYTE)
	96	status = MCHECK_TAIL;
	97	else
	98	status = MCHECK_OK;
	99	break;
	100	}
	101	if (status != MCHECK_OK)
	102	(*abortfunc) (status);
	103	return status;
	104	}
	105
77e1d15a UD	106	void
77e1d15a UD	107	mcheck_check_all ()
8e605e78 UD	108	{
	109	/* Walk through all the active blocks and test whether they were tempered
	110	with. */
	111	struct hdr *runp = root;
	112
30e0f9c3 UD	113	/* Temporarily turn off the checks. */
	114	pedantic = 0;
	115
8e605e78 UD	116	while (runp != NULL)
	117	{
	118	(void) checkhdr (runp);
	119
	120	runp = runp->next;
	121	}
30e0f9c3 UD	122
	123	/* Turn checks on again. */
	124	pedantic = 1;
8e605e78 UD	125	}
	126
	127	static void unlink_blk __P ((struct hdr *ptr));
	128	static void
	129	unlink_blk (ptr)
	130	struct hdr *ptr;
	131	{
	132	if (ptr->next != NULL)
	133	{
	134	ptr->next->prev = ptr->prev;
	135	ptr->next->magic = MAGICWORD ^ ((uintptr_t) ptr->next->prev
	136	+ (uintptr_t) ptr->next->next);
	137	}
	138	if (ptr->prev != NULL)
	139	{
	140	ptr->prev->next = ptr->next;
	141	ptr->prev->magic = MAGICWORD ^ ((uintptr_t) ptr->prev->prev
	142	+ (uintptr_t) ptr->prev->next);
	143	}
	144	else
	145	root = ptr->next;
	146	}
	147
	148	static void link_blk __P ((struct hdr *ptr));
	149	static void
	150	link_blk (hdr)
	151	struct hdr *hdr;
	152	{
	153	hdr->prev = NULL;
	154	hdr->next = root;
	155	root = hdr;
	156	hdr->magic = MAGICWORD ^ (uintptr_t) hdr->next;
	157
	158	/* And the next block. */
	159	if (hdr->next != NULL)
	160	{
	161	hdr->next->prev = hdr;
	162	hdr->next->magic = MAGICWORD ^ ((uintptr_t) hdr
	163	+ (uintptr_t) hdr->next->next);
	164	}
	165	}
	166
a2b08ee5	167	static void freehook __P ((__ptr_t, const __ptr_t));
6d52618b	168	static void
a2b08ee5	169	freehook (ptr, caller)
6d52618b	170	__ptr_t ptr;
a2b08ee5	171	const __ptr_t caller;
6d52618b	172	{
8e605e78	173	if (pedantic)
77e1d15a	174	mcheck_check_all ();
6d52618b UD	175	if (ptr)
	176	{
	177	struct hdr hdr = ((struct hdr ) ptr) - 1;
	178	checkhdr (hdr);
	179	hdr->magic = MAGICFREE;
8e605e78 UD	180	unlink_blk (hdr);
8e605e78 UD	181	hdr->prev = hdr->next = NULL;
6d52618b UD	182	flood (ptr, FREEFLOOD, hdr->size);
	183	ptr = (__ptr_t) hdr;
	184	}
	185	__free_hook = old_free_hook;
a2b08ee5 UD	186	if (old_free_hook != NULL)
	187	(*old_free_hook) (ptr, caller);
	188	else
	189	free (ptr);
6d52618b UD	190	__free_hook = freehook;
	191	}
	192
a2b08ee5	193	static __ptr_t mallochook __P ((__malloc_size_t, const __ptr_t));
6d52618b	194	static __ptr_t
a2b08ee5	195	mallochook (size, caller)
6d52618b	196	__malloc_size_t size;
a2b08ee5	197	const __ptr_t caller;
6d52618b UD	198	{
	199	struct hdr *hdr;
	200
8e605e78	201	if (pedantic)
77e1d15a	202	mcheck_check_all ();
8e605e78	203
6d52618b	204	__malloc_hook = old_malloc_hook;
a2b08ee5 UD	205	if (old_malloc_hook != NULL)
	206	hdr = (struct hdr ) (old_malloc_hook) (sizeof (struct hdr) + size + 1,
	207	caller);
	208	else
	209	hdr = (struct hdr *) malloc (sizeof (struct hdr) + size + 1);
6d52618b UD	210	__malloc_hook = mallochook;
	211	if (hdr == NULL)
	212	return NULL;
	213
	214	hdr->size = size;
8e605e78	215	link_blk (hdr);
6d52618b UD	216	((char *) &hdr[1])[size] = MAGICBYTE;
	217	flood ((__ptr_t) (hdr + 1), MALLOCFLOOD, size);
	218	return (__ptr_t) (hdr + 1);
	219	}
	220
a2b08ee5	221	static __ptr_t reallochook __P ((__ptr_t, __malloc_size_t, const __ptr_t));
6d52618b	222	static __ptr_t
a2b08ee5	223	reallochook (ptr, size, caller)
6d52618b UD	224	__ptr_t ptr;
6d52618b UD	225	__malloc_size_t size;
a2b08ee5	226	const __ptr_t caller;
6d52618b UD	227	{
	228	struct hdr *hdr;
	229	__malloc_size_t osize;
	230
8e605e78	231	if (pedantic)
77e1d15a	232	mcheck_check_all ();
8e605e78	233
6d52618b UD	234	if (ptr)
	235	{
	236	hdr = ((struct hdr *) ptr) - 1;
	237	osize = hdr->size;
	238
	239	checkhdr (hdr);
8e605e78	240	unlink_blk (hdr);
6d52618b UD	241	if (size < osize)
	242	flood ((char *) ptr + size, FREEFLOOD, osize - size);
	243	}
	244	else
	245	{
	246	osize = 0;
	247	hdr = NULL;
	248	}
	249	__free_hook = old_free_hook;
	250	__malloc_hook = old_malloc_hook;
	251	__realloc_hook = old_realloc_hook;
a2b08ee5 UD	252	if (old_realloc_hook != NULL)
	253	hdr = (struct hdr ) (old_realloc_hook) ((__ptr_t) hdr,
	254	sizeof (struct hdr) + size + 1,
	255	caller);
	256	else
	257	hdr = (struct hdr *) realloc ((__ptr_t) hdr,
	258	sizeof (struct hdr) + size + 1);
6d52618b UD	259	__free_hook = freehook;
	260	__malloc_hook = mallochook;
	261	__realloc_hook = reallochook;
	262	if (hdr == NULL)
	263	return NULL;
	264
	265	hdr->size = size;
8e605e78	266	link_blk (hdr);
6d52618b UD	267	((char *) &hdr[1])[size] = MAGICBYTE;
	268	if (size > osize)
	269	flood ((char *) (hdr + 1) + osize, MALLOCFLOOD, size - osize);
	270	return (__ptr_t) (hdr + 1);
	271	}
	272
159a2e1a AJ	273	static void mabort __P ((enum mcheck_status status))
159a2e1a AJ	274	__attribute__ ((noreturn));
6d52618b UD	275	static void
	276	mabort (status)
	277	enum mcheck_status status;
	278	{
	279	const char *msg;
	280	switch (status)
	281	{
	282	case MCHECK_OK:
9756dfe1	283	msg = _("memory is consistent, library is buggy\n");
6d52618b UD	284	break;
6d52618b UD	285	case MCHECK_HEAD:
9756dfe1	286	msg = _("memory clobbered before allocated block\n");
6d52618b UD	287	break;
6d52618b UD	288	case MCHECK_TAIL:
9756dfe1	289	msg = _("memory clobbered past end of allocated block\n");
6d52618b UD	290	break;
6d52618b UD	291	case MCHECK_FREE:
9756dfe1	292	msg = _("block freed twice\n");
6d52618b UD	293	break;
6d52618b UD	294	default:
9756dfe1	295	msg = _("bogus mcheck_status, library is buggy\n");
6d52618b UD	296	break;
	297	}
	298	#ifdef _LIBC
	299	__libc_fatal (msg);
	300	#else
9756dfe1	301	fprintf (stderr, "mcheck: %s", msg);
6d52618b UD	302	fflush (stderr);
	303	abort ();
	304	#endif
	305	}
	306
c4563d2d	307	static int mcheck_used;
6d52618b UD	308
	309	int
	310	mcheck (func)
	311	void (*func) __P ((enum mcheck_status));
	312	{
	313	abortfunc = (func != NULL) ? func : &mabort;
	314
	315	/* These hooks may not be safely inserted if malloc is already in use. */
9756dfe1	316	if (__malloc_initialized <= 0 && !mcheck_used)
6d52618b UD	317	{
	318	old_free_hook = __free_hook;
	319	__free_hook = freehook;
	320	old_malloc_hook = __malloc_hook;
	321	__malloc_hook = mallochook;
	322	old_realloc_hook = __realloc_hook;
	323	__realloc_hook = reallochook;
	324	mcheck_used = 1;
	325	}
	326
	327	return mcheck_used ? 0 : -1;
	328	}
	329
8e605e78 UD	330	int
	331	mcheck_pedantic (func)
	332	void (*func) __P ((enum mcheck_status));
	333	{
77e1d15a UD	334	int res = mcheck (func);
	335	if (res == 0)
	336	pedantic = 1;
	337	return res;
8e605e78 UD	338	}
8e605e78 UD	339
6d52618b UD	340	enum mcheck_status
	341	mprobe (__ptr_t ptr)
	342	{
997a4165	343	return mcheck_used ? checkhdr (((struct hdr *) ptr) - 1) : MCHECK_DISABLED;
6d52618b	344	}