X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Frealloc.c;h=36aeecc41b7203574b658edaebb6bd9975c9f737;hb=5518d301980bdc0f60b1b5d58b140004dfda490e;hp=1f82e75aa9baa3ce7c4330c8d98c39234fcec53c;hpb=66d38967ea1995b22c06fbe3645b685b081355ce;p=gnulib.git

diff --git a/lib/realloc.c b/lib/realloc.c
index 1f82e75aa..36aeecc41 100644
--- a/lib/realloc.c
+++ b/lib/realloc.c
@@ -1,10 +1,12 @@
-/* Work around bug on some systems where realloc (NULL, n) fails.
-   Copyright (C) 1997 Free Software Foundation, Inc.
+/* realloc() function that is glibc compatible.
 
-   This program is free software; you can redistribute it and/or modify
+   Copyright (C) 1997, 2003-2004, 2006-2007, 2009-2010 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
-   the Free Software Foundation; either version 2, or (at your option)
-   any later version.
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
 
    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ -12,30 +14,75 @@
    GNU General Public License for more details.
 
    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.  */
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+/* written by Jim Meyering and Bruno Haible */
 
-/* written by Jim Meyering */
+#include <config.h>
+
+/* Only the AC_FUNC_REALLOC macro defines 'realloc' already in config.h.  */
+#ifdef realloc
+# define NEED_REALLOC_GNU 1
+#endif
 
-#if HAVE_CONFIG_H
-# include <config.h>
+/* Infer the properties of the system's malloc function.
+   Only the AC_FUNC_MALLOC macro defines 'malloc' already in config.h.  */
+#if GNULIB_MALLOC_GNU && !defined malloc
+# define SYSTEM_MALLOC_GLIBC_COMPATIBLE 1
 #endif
+
+/* Below we want to call the system's malloc and realloc.
+   Undefine the symbols here so that including <stdlib.h> provides a
+   declaration of malloc(), not of rpl_malloc(), and likewise for realloc.  */
+#undef malloc
 #undef realloc
 
-#include <sys/types.h>
+/* Specification.  */
+#include <stdlib.h>
+
+#include <errno.h>
 
-char *malloc ();
-char *realloc ();
+/* Below we want to call the system's malloc and realloc.
+   Undefine the symbols, if they were defined by gnulib's <stdlib.h>
+   replacement.  */
+#undef malloc
+#undef realloc
 
 /* Change the size of an allocated block of memory P to N bytes,
-   with error checking.  If P is NULL, use malloc.  */
+   with error checking.  If N is zero, change it to 1.  If P is NULL,
+   use malloc.  */
 
-char *
-rpl_realloc (p, n)
-     char *p;
-     size_t n;
+void *
+rpl_realloc (void *p, size_t n)
 {
-  if (p == 0)
-    return malloc (n);
-  return realloc (p, n);
+  void *result;
+
+#if NEED_REALLOC_GNU
+  if (n == 0)
+    {
+      n = 1;
+
+      /* In theory realloc might fail, so don't rely on it to free.  */
+      free (p);
+      p = NULL;
+    }
+#endif
+
+  if (p == NULL)
+    {
+#if GNULIB_REALLOC_GNU && !NEED_REALLOC_GNU && !SYSTEM_MALLOC_GLIBC_COMPATIBLE
+      if (n == 0)
+        n = 1;
+#endif
+      result = malloc (n);
+    }
+  else
+    result = realloc (p, n);
+
+#if !HAVE_REALLOC_POSIX
+  if (result == NULL)
+    errno = ENOMEM;
+#endif
+
+  return result;
 }