From: Todd C. Miller <Todd.Miller@courtesan.com>
Date: Wed, 31 Dec 2003 22:46:08 +0000 (+0000)
Subject: Add a zero_bytes() function to do the equivalent of bzero in such a
X-Git-Tag: SUDO_1_6_8~287
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=de5e16b22ff3ce7f5e65b2b262a196fa6dd14126;p=sudo

Add a zero_bytes() function to do the equivalent of bzero in such a
way that will heopfully not be optimized away by sneaky compilers.
---

diff --git a/zero_bytes.c b/zero_bytes.c
new file mode 100644
index 000000000..f24bf8474
--- /dev/null
+++ b/zero_bytes.c
@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 1999, 2001 Todd C. Miller <Todd.Miller@courtesan.com>
+ * 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. The name of the author may not be used to endorse or promote products
+ *    derived from this software without specific prior written permission.
+ *
+ * 4. Products derived from this software may not be called "Sudo" nor
+ *    may "Sudo" appear in their names without specific prior written
+ *    permission from the author.
+ *
+ * THIS SOFTWARE IS PROVIDED ``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.
+ */
+
+#include <sys/types.h>
+
+#include "config.h"
+
+#ifndef lint
+static const char rcsid[] = "$Sudo$";
+#endif /* lint */
+
+/*
+ * Like bzero(3) but with a volatile pointer.  The hope is that
+ * the compiler will not be able to optimize away this function.
+ */
+void
+zero_bytes(v, n)
+    volatile VOID *v;
+    size_t n;
+{
+    volatile char *p, *ep;
+
+    for (p = v, ep = p + n; p < ep; p++)
+	*p = 0;
+    return;
+}