1 files changed, 97 insertions, 0 deletions
diff --git a/usr.bin/xlint/lint2/mem2.c b/usr.bin/xlint/lint2/mem2.c
new file mode 100644
index 0000000..06d7491
--- /dev/null
+++ b/usr.bin/xlint/lint2/mem2.c
@@ -0,0 +1,97 @@
+/*	$NetBSD: mem2.c,v 1.3 1995/10/02 17:27:11 jpo Exp $	*/
+
+/*
+ * Copyright (c) 1994, 1995 Jochen Pohl
+ * 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. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *      This product includes software developed by Jochen Pohl for
+ *	The NetBSD Project.
+ * 4. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
+ */
+
+#ifndef lint
+static char rcsid[] = "$NetBSD: mem2.c,v 1.3 1995/10/02 17:27:11 jpo Exp $";
+#endif
+
+#include <sys/param.h>
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <unistd.h>
+#include <string.h>
+#include <err.h>
+
+#include "lint2.h"
+
+/* length of new allocated memory blocks */
+static size_t	mblklen;
+
+/* offset of next free byte in mbuf */
+static size_t	nxtfree;
+
+/* current buffer to server memory requests from */
+static void	*mbuf;
+
+void
+initmem()
+{
+	int	pgsz;
+
+	pgsz = getpagesize();
+	mblklen = ((MBLKSIZ + pgsz - 1) / pgsz) * pgsz;
+
+	nxtfree = mblklen;
+}
+
+/*
+ * Allocate memory in large chunks to avoid space and time overhead of
+ * malloc(). This is possible because memory allocated by xalloc()
+ * need never to be freed.
+ */
+void *
+xalloc(sz)
+	size_t	sz;
+{
+	void	*ptr;
+	int	prot, flags;
+
+	sz = ALIGN(sz);
+	if (nxtfree + sz > mblklen) {
+		/* use mmap() instead of malloc() to avoid malloc overhead. */
+		prot = PROT_READ | PROT_WRITE;
+		flags = MAP_ANON | MAP_PRIVATE;
+		mbuf = mmap(NULL, mblklen, prot, flags, -1, (off_t)0);
+		if (mbuf == (void *)-1)
+			err(1, "can't map memory");
+		if (ALIGN((u_long)mbuf) != (u_long)mbuf)
+			errx(1, "mapped address is not aligned");
+		(void)memset(mbuf, 0, mblklen);
+		nxtfree = 0;
+	}
+
+	ptr = (char *)mbuf + nxtfree;
+	nxtfree += sz;
+
+	return (ptr);
+}