/* xmalloc.c -- malloc with out of memory checking
Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
- 1999, 2000, 2002, 2003 Free Software Foundation, Inc.
+ 1999, 2000, 2002, 2003, 2004, 2005, 2006 Free Software Foundation,
+ Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software Foundation,
- Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+ Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
-#if HAVE_CONFIG_H
-# include <config.h>
-#endif
+#include <config.h>
#include "xalloc.h"
#include <stdlib.h>
+#include <string.h>
-#include "gettext.h"
-#define _(msgid) gettext (msgid)
-#define N_(msgid) msgid
-
-#include "error.h"
-#include "exit.h"
-#include "exitfail.h"
-
-/* The following tests require AC_PREREQ(2.54). */
-
-#ifndef HAVE_MALLOC
-"you must run the autoconf test for a GNU libc compatible malloc"
+#ifndef SIZE_MAX
+# define SIZE_MAX ((size_t) -1)
#endif
-#ifndef HAVE_REALLOC
-"you must run the autoconf test for a GNU libc compatible realloc"
+/* 1 if calloc is known to be compatible with GNU calloc. This
+ matters if we are not also using the calloc module, which defines
+ HAVE_CALLOC and supports the GNU API even on non-GNU platforms. */
+#if defined HAVE_CALLOC || defined __GLIBC__
+enum { HAVE_GNU_CALLOC = 1 };
+#else
+enum { HAVE_GNU_CALLOC = 0 };
#endif
-/* If non NULL, call this function when memory is exhausted. */
-void (*xalloc_fail_func) (void) = 0;
+/* Allocate an array of N objects, each with S bytes of memory,
+ dynamically, with error checking. S must be nonzero. */
-/* If XALLOC_FAIL_FUNC is NULL, or does return, display this message
- before exiting when memory is exhausted. Goes through gettext. */
-char const xalloc_msg_memory_exhausted[] = N_("memory exhausted");
+static inline void *
+xnmalloc_inline (size_t n, size_t s)
+{
+ void *p;
+ if (xalloc_oversized (n, s) || (! (p = malloc (n * s)) && n != 0))
+ xalloc_die ();
+ return p;
+}
-void
-xalloc_die (void)
+void *
+xnmalloc (size_t n, size_t s)
{
- if (xalloc_fail_func)
- (*xalloc_fail_func) ();
- error (exit_failure, 0, "%s", _(xalloc_msg_memory_exhausted));
- /* The `noreturn' cannot be given to error, since it may return if
- its first argument is 0. To help compilers understand the
- xalloc_die does terminate, call exit. */
- exit (EXIT_FAILURE);
+ return xnmalloc_inline (n, s);
}
/* Allocate N bytes of memory dynamically, with error checking. */
void *
xmalloc (size_t n)
{
- void *p;
+ return xnmalloc_inline (n, 1);
+}
- p = malloc (n);
- if (p == 0)
+/* Change the size of an allocated block of memory P to an array of N
+ objects each of S bytes, with error checking. S must be nonzero. */
+
+static inline void *
+xnrealloc_inline (void *p, size_t n, size_t s)
+{
+ if (xalloc_oversized (n, s) || (! (p = realloc (p, n * s)) && n != 0))
xalloc_die ();
return p;
}
+void *
+xnrealloc (void *p, size_t n, size_t s)
+{
+ return xnrealloc_inline (p, n, s);
+}
+
/* Change the size of an allocated block of memory P to N bytes,
with error checking. */
void *
xrealloc (void *p, size_t n)
{
- p = realloc (p, n);
- if (p == 0)
- xalloc_die ();
- return p;
+ return xnrealloc_inline (p, n, 1);
+}
+
+
+/* If P is null, allocate a block of at least *PN such objects;
+ otherwise, reallocate P so that it contains more than *PN objects
+ each of S bytes. *PN must be nonzero unless P is null, and S must
+ be nonzero. Set *PN to the new number of objects, and return the
+ pointer to the new block. *PN is never set to zero, and the
+ returned pointer is never null.
+
+ Repeated reallocations are guaranteed to make progress, either by
+ allocating an initial block with a nonzero size, or by allocating a
+ larger block.
+
+ In the following implementation, nonzero sizes are doubled so that
+ repeated reallocations have O(N log N) overall cost rather than
+ O(N**2) cost, but the specification for this function does not
+ guarantee that sizes are doubled.
+
+ Here is an example of use:
+
+ int *p = NULL;
+ size_t used = 0;
+ size_t allocated = 0;
+
+ void
+ append_int (int value)
+ {
+ if (used == allocated)
+ p = x2nrealloc (p, &allocated, sizeof *p);
+ p[used++] = value;
+ }
+
+ This causes x2nrealloc to allocate a block of some nonzero size the
+ first time it is called.
+
+ To have finer-grained control over the initial size, set *PN to a
+ nonzero value before calling this function with P == NULL. For
+ example:
+
+ int *p = NULL;
+ size_t used = 0;
+ size_t allocated = 0;
+ size_t allocated1 = 1000;
+
+ void
+ append_int (int value)
+ {
+ if (used == allocated)
+ {
+ p = x2nrealloc (p, &allocated1, sizeof *p);
+ allocated = allocated1;
+ }
+ p[used++] = value;
+ }
+
+ */
+
+static inline void *
+x2nrealloc_inline (void *p, size_t *pn, size_t s)
+{
+ size_t n = *pn;
+
+ if (! p)
+ {
+ if (! n)
+ {
+ /* The approximate size to use for initial small allocation
+ requests, when the invoking code specifies an old size of
+ zero. 64 bytes is the largest "small" request for the
+ GNU C library malloc. */
+ enum { DEFAULT_MXFAST = 64 };
+
+ n = DEFAULT_MXFAST / s;
+ n += !n;
+ }
+ }
+ else
+ {
+ if (SIZE_MAX / 2 / s < n)
+ xalloc_die ();
+ n *= 2;
+ }
+
+ *pn = n;
+ return xrealloc (p, n * s);
}
-/* Allocate memory for N elements of S bytes, with error checking. */
+void *
+x2nrealloc (void *p, size_t *pn, size_t s)
+{
+ return x2nrealloc_inline (p, pn, s);
+}
+
+/* If P is null, allocate a block of at least *PN bytes; otherwise,
+ reallocate P so that it contains more than *PN bytes. *PN must be
+ nonzero unless P is null. Set *PN to the new block's size, and
+ return the pointer to the new block. *PN is never set to zero, and
+ the returned pointer is never null. */
+
+void *
+x2realloc (void *p, size_t *pn)
+{
+ return x2nrealloc_inline (p, pn, 1);
+}
+
+/* Allocate S bytes of zeroed memory dynamically, with error checking.
+ There's no need for xnzalloc (N, S), since it would be equivalent
+ to xcalloc (N, S). */
+
+void *
+xzalloc (size_t s)
+{
+ return memset (xmalloc (s), 0, s);
+}
+
+/* Allocate zeroed memory for N elements of S bytes, with error
+ checking. S must be nonzero. */
void *
xcalloc (size_t n, size_t s)
{
void *p;
-
- p = calloc (n, s);
- if (p == 0)
+ /* Test for overflow, since some calloc implementations don't have
+ proper overflow checks. But omit overflow and size-zero tests if
+ HAVE_GNU_CALLOC, since GNU calloc catches overflow and never
+ returns NULL if successful. */
+ if ((! HAVE_GNU_CALLOC && xalloc_oversized (n, s))
+ || (! (p = calloc (n, s)) && (HAVE_GNU_CALLOC || n != 0)))
xalloc_die ();
return p;
}
+
+/* Clone an object P of size S, with error checking. There's no need
+ for xnmemdup (P, N, S), since xmemdup (P, N * S) works without any
+ need for an arithmetic overflow check. */
+
+void *
+xmemdup (void const *p, size_t s)
+{
+ return memcpy (xmalloc (s), p, s);
+}
+
+/* Clone STRING. */
+
+char *
+xstrdup (char const *string)
+{
+ return xmemdup (string, strlen (string) + 1);
+}
projects / gnulib.git / blobdiff