--- /dev/null
+/* Memory allocation with expensive empty allocations.
+ Copyright (C) 2003 Free Software Foundation, Inc.
+ Written by Bruno Haible <bruno@clisp.org>, 2003,
+ based on prior work by Jim Meyering.
+
+ 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.
+
+ This program 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 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. */
+
+#ifndef _EEALLOC_H
+#define _EEALLOC_H
+
+/* malloc() and realloc() are allowed to return NULL when asked to allocate
+ a memory block of 0 bytes; this is not an out-of-memory condition.
+ (See ISO C 99 section 7.20.3.) In some places, this is not welcome,
+ because it requires extra checking (so as not to confuse a zero-sized
+ allocation with an out-of-memory condition). This file provides
+ malloc()/realloc() workalikes which return non-NULL pointers for
+ succeeding zero-sized allocations. GNU libc already defines malloc()
+ and realloc() this way; on such platforms the workalikes are aliased
+ to the original malloc()/realloc() functions. */
+
+#include <stdlib.h>
+
+#if MALLOC_0_IS_NONNULL
+# define eemalloc malloc
+#else
+static inline void *
+eemalloc (size_t n)
+{
+ /* If n is zero, allocate a 1-byte block. */
+ if (n == 0)
+ n = 1;
+ return malloc (n);
+}
+#endif
+
+#if REALLOC_0_IS_NONNULL
+# define eerealloc realloc
+#else
+static inline void *
+eerealloc (void *p, size_t n)
+{
+ /* If n is zero, allocate or keep a 1-byte block. */
+ if (n == 0)
+ n = 1;
+ return realloc (p, n);
+}
+#endif
+
+/* Maybe we should also define variants
+ eenmalloc (size_t n, size_t s) - behaves like eemalloc (n * s)
+ eezalloc (size_t n) - like eemalloc followed by memset 0
+ eecalloc (size_t n, size_t s) - like eemalloc (n * s) followed by memset 0
+ eenrealloc (void *p, size_t n, size_t s) - like eerealloc (p, n * s)
+ If this would be useful in your application. please speak up. */
+
+#endif /* _EEALLOC_H */
--- /dev/null
+# eealloc.m4 serial 1
+dnl Copyright (C) 2003 Free Software Foundation, Inc.
+dnl This file is free software, distributed under the terms of the GNU
+dnl General Public License. As a special exception to the GNU General
+dnl Public License, this file may be distributed as part of a program
+dnl that contains a configuration script generated by Autoconf, under
+dnl the same distribution terms as the rest of that program.
+
+AC_DEFUN([gl_EEALLOC],
+[
+ AC_REQUIRE([gl_EEMALLOC])
+ AC_REQUIRE([gl_EEREALLOC])
+ AC_REQUIRE([AC_C_INLINE])
+])
+
+AC_DEFUN([gl_EEMALLOC],
+[
+ _AC_FUNC_MALLOC_IF(
+ [gl_cv_func_malloc_0_nonnull=1],
+ [gl_cv_func_malloc_0_nonnull=0])
+ AC_DEFINE_UNQUOTED([MALLOC_0_IS_NONNULL], $gl_cv_func_malloc_0_nonnull,
+ [If malloc(0) is != NULL, define this to 1. Otherwise define this
+ to 0.])
+])
+
+AC_DEFUN([gl_EEREALLOC],
+[
+ _AC_FUNC_REALLOC_IF(
+ [gl_cv_func_realloc_0_nonnull=1],
+ [gl_cv_func_realloc_0_nonnull=0])
+ AC_DEFINE_UNQUOTED([REALLOC_0_IS_NONNULL], $gl_cv_func_realloc_0_nonnull,
+ [If realloc(NULL,0) is != NULL, define this to 1. Otherwise define this
+ to 0.])
+])