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+/* GLIB - Library of useful routines for C programming
+ * Copyright (C) 1995-1997 Peter Mattis, Spencer Kimball and Josh MacDonald
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the
+ * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+ * Boston, MA 02111-1307, USA.
+ */
+
+/*
+ * Modified by the GLib Team and others 1997-2000. See the AUTHORS
+ * file for a list of people on the GLib Team. See the ChangeLog
+ * files for a list of changes. These files are distributed with
+ * GLib at ftp://ftp.gtk.org/pub/gtk/.
+ */
+
+#if defined(G_DISABLE_SINGLE_INCLUDES) && !defined (__GLIB_H_INSIDE__) && !defined (GLIB_COMPILATION)
+#error "Only <glib.h> can be included directly."
+#endif
+
+#ifndef __G_ALLOCA_H__
+#define __G_ALLOCA_H__
+
+#include <glib/gtypes.h>
+
+#ifdef __GNUC__
+/* GCC does the right thing */
+# undef alloca
+# define alloca(size) __builtin_alloca (size)
+#elif defined (GLIB_HAVE_ALLOCA_H)
+/* a native and working alloca.h is there */
+# include <alloca.h>
+#else /* !__GNUC__ && !GLIB_HAVE_ALLOCA_H */
+# if defined(_MSC_VER) || defined(__DMC__)
+# include <malloc.h>
+# define alloca _alloca
+# else /* !_MSC_VER && !__DMC__ */
+# ifdef _AIX
+# pragma alloca
+# else /* !_AIX */
+# ifndef alloca /* predefined by HP cc +Olibcalls */
+G_BEGIN_DECLS
+char *alloca ();
+G_END_DECLS
+# endif /* !alloca */
+# endif /* !_AIX */
+# endif /* !_MSC_VER && !__DMC__ */
+#endif /* !__GNUC__ && !GLIB_HAVE_ALLOCA_H */
+
+/**
+ * g_alloca:
+ * @size: number of bytes to allocate.
+ *
+ * Allocates @size bytes on the stack; these bytes will be freed when the current
+ * stack frame is cleaned up. This macro essentially just wraps the alloca()
+ * function present on most UNIX variants.
+ * Thus it provides the same advantages and pitfalls as alloca():
+ * <variablelist>
+ * <varlistentry><term></term><listitem><para>
+ * + alloca() is very fast, as on most systems it's implemented by just adjusting
+ * the stack pointer register.
+ * </para></listitem></varlistentry>
+ * <varlistentry><term></term><listitem><para>
+ * + It doesn't cause any memory fragmentation, within its scope, separate alloca()
+ * blocks just build up and are released together at function end.
+ * </para></listitem></varlistentry>
+ * <varlistentry><term></term><listitem><para>
+ * - Allocation sizes have to fit into the current stack frame. For instance in a
+ * threaded environment on Linux, the per-thread stack size is limited to 2 Megabytes,
+ * so be sparse with alloca() uses.
+ * </para></listitem></varlistentry>
+ * <varlistentry><term></term><listitem><para>
+ * - Allocation failure due to insufficient stack space is not indicated with a %NULL
+ * return like e.g. with malloc(). Instead, most systems probably handle it the same
+ * way as out of stack space situations from infinite function recursion, i.e.
+ * with a segmentation fault.
+ * </para></listitem></varlistentry>
+ * <varlistentry><term></term><listitem><para>
+ * - Special care has to be taken when mixing alloca() with GNU C variable sized arrays.
+ * Stack space allocated with alloca() in the same scope as a variable sized array
+ * will be freed together with the variable sized array upon exit of that scope, and
+ * not upon exit of the enclosing function scope.
+ * </para></listitem></varlistentry>
+ * </variablelist>
+ *
+ * Returns: space for @size bytes, allocated on the stack
+ */
+#define g_alloca(size) alloca (size)
+/**
+ * g_newa:
+ * @struct_type: Type of memory chunks to be allocated
+ * @n_structs: Number of chunks to be allocated
+ *
+ * Wraps g_alloca() in a more typesafe manner.
+ *
+ * Returns: Pointer to stack space for @n_structs chunks of type @struct_type
+ */
+#define g_newa(struct_type, n_structs) ((struct_type*) g_alloca (sizeof (struct_type) * (gsize) (n_structs)))
+
+#endif /* __G_ALLOCA_H__ */