1 files changed, 127 insertions, 0 deletions
diff --git a/alloc.c b/alloc.c
new file mode 100644
index 0000000..31f2330
--- /dev/null
+++ b/alloc.c
@@ -0,0 +1,127 @@
+/*	$NetBSD: alloc.c,v 1.10 2007/12/12 22:55:42 lukem Exp $	*/
+
+/*
+ * Copyright (c) 2002 Marc Espie.
+ *
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE OPENBSD PROJECT 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 OPENBSD
+ * PROJECT 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.
+ */
+
+/*
+ * area-based allocation built on malloc/free
+ */
+#include <sys/cdefs.h>
+__RCSID("$NetBSD: alloc.c,v 1.10 2007/12/12 22:55:42 lukem Exp $");
+
+#include "sh.h"
+
+struct link {
+	struct link *prev;
+	struct link *next;
+};
+
+Area *
+ainit(Area *ap)
+{
+	ap->freelist = NULL;
+	return ap;
+}
+
+void
+afreeall(Area *ap)
+{
+	struct link *l, *l2;
+
+	for (l = ap->freelist; l != NULL; l = l2) {
+		l2 = l->next;
+		free(l);
+	}
+	ap->freelist = NULL;
+}
+
+#define L2P(l)	( (void *)(((char *)(l)) + sizeof(struct link)) )
+#define P2L(p)	( (struct link *)(((char *)(p)) - sizeof(struct link)) )
+
+/* coverity[+alloc] */
+void *
+alloc(size_t size, Area *ap)
+{
+	struct link *l;
+
+	l = malloc(sizeof(struct link) + size);
+	if (l == NULL)
+		internal_errorf(1, "unable to allocate memory");
+	l->next = ap->freelist;
+	l->prev = NULL;
+	if (ap->freelist)
+		ap->freelist->prev = l;
+	ap->freelist = l;
+
+	return L2P(l);
+}
+
+/* coverity[+alloc] */
+/* coverity[+free : arg-0] */
+void *
+aresize(void *ptr, size_t size, Area *ap)
+{
+	struct link *l, *l2, *lprev, *lnext;
+
+	if (ptr == NULL)
+		return alloc(size, ap);
+
+	l = P2L(ptr);
+	lprev = l->prev;
+	lnext = l->next;
+
+	l2 = realloc(l, sizeof(struct link) + size);
+	if (l2 == NULL)
+		internal_errorf(1, "unable to allocate memory");
+	if (lprev)
+		lprev->next = l2;
+	else
+		ap->freelist = l2;
+	if (lnext)
+		lnext->prev = l2;
+
+	return L2P(l2);
+}
+
+/* coverity[+free : arg-0] */
+void
+afree(void *ptr, Area *ap)
+{
+	struct link *l;
+
+	if (!ptr)
+		return;
+
+	l = P2L(ptr);
+
+	if (l->prev)
+		l->prev->next = l->next;
+	else
+		ap->freelist = l->next;
+	if (l->next)
+		l->next->prev = l->prev;
+
+	free(l);
+}