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+/*
+ File: high_water_alloc.c
+
+ Copyright (C) 2001-2002 Silicon Graphics, Inc. All Rights Reserved.
+
+ This program is free software; you can redistribute it and/or
+ modify it under the terms of the GNU Library General Public
+ License as published by the Free Software Foundation; either
+ version 2 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
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ Library General Public License for more details.
+
+ You should have received a copy of the GNU Library 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.
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include "misc.h"
+
+int high_water_alloc(void **buf, size_t *bufsize, size_t newsize)
+{
+#define CHUNK_SIZE 256
+ /*
+ * Goal here is to avoid unnecessary memory allocations by
+ * using static buffers which only grow when necessary.
+ * Size is increased in fixed size chunks (CHUNK_SIZE).
+ */
+ if (*bufsize < newsize) {
+ void *newbuf;
+
+ newsize = (newsize + CHUNK_SIZE-1) & ~(CHUNK_SIZE-1);
+ newbuf = realloc(*buf, newsize);
+ if (!newbuf)
+ return 1;
+
+ *buf = newbuf;
+ *bufsize = newsize;
+ }
+ return 0;
+}