Updated by gnulib-sync

1 files changed, 174 insertions, 64 deletions

diff --git a/lib/xmalloc.c b/lib/xmalloc.c
index a71dc3584..13c249026 100644
--- a/lib/xmalloc.c
+++ b/lib/xmalloc.c
@@ -1,5 +1,7 @@
 /* xmalloc.c -- malloc with out of memory checking
-   Copyright (C) 1990-1997, 98, 99 Free Software Foundation, Inc.
+
+   Copyright (C) 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
+   1999, 2000, 2002, 2003, 2004 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
@@ -19,64 +21,31 @@
 # include <config.h>
 #endif
 
-#include <sys/types.h>
-
-#include <mailutils/error.h>
-
-#if STDC_HEADERS
-# include <stdlib.h>
-#else
-void *calloc ();
-void *malloc ();
-void *realloc ();
-void free ();
-#endif
-
-#if ENABLE_NLS
-# include <libintl.h>
-# define _(Text) gettext (Text)
-#else
-# define textdomain(Domain)
-# define _(Text) Text
-#endif
-#define N_(Text) Text
-
-#include "error.h"
 #include "xalloc.h"
 
-#ifndef EXIT_FAILURE
-# define EXIT_FAILURE 1
-#endif
-
-#ifndef HAVE_MALLOC
-# error "you must run the autoconf test for a properly working malloc -- see malloc.m4"
-#endif
+#include <stdlib.h>
+#include <string.h>
 
-#ifndef HAVE_REALLOC
-# error "you must run the autoconf test for a properly working realloc -- see realloc.m4"
+#ifndef SIZE_MAX
+# define SIZE_MAX ((size_t) -1)
 #endif
 
-/* Exit value when the requested amount of memory is not available.
-   The caller may set it to some other value.  */
-int xalloc_exit_failure = EXIT_FAILURE;
-
-/* If non NULL, call this function when memory is exhausted. */
-void (*xalloc_fail_func) PARAMS ((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) ();
-  mu_error ("%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 (xalloc_exit_failure);
+  return xnmalloc_inline (n, s);
 }
 
 /* Allocate N bytes of memory dynamically, with error checking.  */
@@ -84,36 +53,177 @@ xalloc_die (void)
 void *
 xmalloc (size_t n)
 {
-  void *p;
+  return xnmalloc_inline (n, 1);
+}
+
+/* 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.  */
 
-  p = malloc (n);
-  if (p == 0)
+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.
-   If P is NULL, run xmalloc.  */
+   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);
 }
 
-/* Allocate memory for N elements of S bytes, with error checking.  */
+
+/* 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);
+}
+
+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.  */
+  if (xalloc_oversized (n, s) || (! (p = calloc (n, s)) && 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);
+}