Import of the contiki-2.x development code from the SICS internal CVS server

core/lib/malloc_compact.c

@@ -0,0 +1,133 @@
+/*
+ * Copyright (c) 2006, Swedish Institute of Computer Science
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the Institute nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE INSTITUTE AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE INSTITUTE OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * @(#)$Id: malloc_compact.c,v 1.1 2006/06/17 22:41:18 adamdunkels Exp $
+ */
+
+#include <stdlib.h>
+#include <string.h>
+
+#ifdef MALLOC_TEST
+#include "malloc.h"
+#else
+#include "contiki.h"
+#include "lib/malloc.h"
+#endif /* !MALLOC_TEST */
+
+#define handle nx
+
+void
+malloc_unlock(void **h)
+{
+    struct __freelist *t = *h;
+    t = &t[-1];
+    t->handle = (void *)h;
+}
+
+void
+malloc_lock(void **h)
+{
+    struct __freelist *t = *h;
+    t = &t[-1];
+    t->handle = NULL;
+}
+
+static int
+compact1(struct __freelist **flp)
+{
+    struct __freelist *fp = *flp, *fp2;
+    struct __freelist *ap1, *ap2;
+    struct __freelist *end = (struct __freelist *)__brkval;
+
+    ap1 = (void *)(((char *)fp) + sizeof(struct __freelist) + fp->sz);
+    if (ap1 >= end)
+        return 0;
+    if (ap1->handle == NULL)
+        return 0;
+
+    ap2 = (void *)(((char *)ap1) + sizeof(struct __freelist) + ap1->sz);
+    fp2 = fp->nx;
+
+    if (ap2 != fp2) {		/* 2 blocks become 2 */
+        size_t s = fp->sz;
+
+	fp->sz = ap1->sz;
+	fp->handle = ap1->handle;
+	memcpy(&fp[1], &ap1[1], ap1->sz);
+	*(void **)(fp->handle) = &fp[1];
+
+	fp = (void *)(((char *)fp) + sizeof(struct __freelist) + fp->sz);
+	fp->sz = s;
+	fp->nx = fp2;
+	*flp = fp;
+	return 1;
+    }
+
+    if (ap2 == fp2) {		/* 3 blocks become 2 */
+        size_t s = fp->sz + fp2->sz + sizeof(struct __freelist);
+
+	fp->sz = ap1->sz;
+	fp->handle = ap1->handle;
+	memcpy(&fp[1], &ap1[1], ap1->sz);
+	*(void **)(fp->handle) = &fp[1];
+
+	fp = (void *)(((char *)fp) + sizeof(struct __freelist) + fp->sz);
+	fp->sz = s;
+	fp->nx = fp2->nx;
+	*flp = fp;
+	return 1;
+    }
+
+    return 0;
+}
+
+void
+malloc_compact(void)
+{
+    struct __freelist **flp;
+
+    flp = &__flp;
+    while (*flp != NULL) {
+      while (compact1(flp))
+	;
+      flp = &((*flp)->nx);
+    }
+}
+
+void
+malloc_compact_one(void)
+{
+    struct __freelist **flp;
+
+    flp = &__flp;
+    while (*flp != NULL) {
+      if (compact1(flp))
+	return ;
+      flp = &((*flp)->nx);
+    }
+}