Test: MULTI/EXEC tests moved into multi.tcl.

[redis.git] / src / memtest.c

diff --git a/src/memtest.c b/src/memtest.c
index 88c7213af7d4426c7cd1e462fd25de7ba3257f7f..82da27c8bc7baf2a7e7c49786e10aa3ae6aa65e1 100644 (file)
--- a/src/memtest.c
+++ b/src/memtest.c
@@ -1,3 +1,32 @@
+/*
+ * Copyright (c) 2009-2012, Salvatore Sanfilippo <antirez at gmail dot 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:
+ *
+ *   * Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *   * 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.
+ *   * Neither the name of Redis 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 COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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.
+ */
+
 #include <stdlib.h>
 #include <stdio.h>
 #include <string.h>
@@ -6,6 +35,7 @@
 #include <errno.h>
 #include <termios.h>
 #include <sys/ioctl.h>
+#include "config.h"
 
 #if (ULONG_MAX == 4294967295UL)
 #define MEMTEST_32BIT
@@ -211,6 +241,36 @@ void memtest_test(size_t megabytes, int passes) {
     }
 }
 
+/* This is a fast O(N) best effort memory test, only ZERO-ONE tests and
+ * checkerboard tests are performed, without pauses between setting and
+ * reading the value, so this can only detect a subclass of permanent errors.
+ *
+ * However the function does not destroy the content of the memory tested that
+ * is left unmodified.
+ *
+ * If a memory error is detected, 1 is returned. Otherwise 0 is returned. */
+int memtest_non_destructive(void *addr, size_t size) {
+    volatile unsigned long *p = addr;
+    unsigned long val;
+    size_t j;
+
+    size /= sizeof(unsigned long);
+    for (j = 0; j < size; j++) {
+        val = p[j];
+
+        p[j] = 0; if (p[j] != 0) goto err;
+        p[j] = (unsigned long)-1; if (p[j] != (unsigned long)-1) goto err;
+        p[j] = ULONG_ONEZERO; if (p[j] != ULONG_ONEZERO) goto err;
+        p[j] = ULONG_ZEROONE; if (p[j] != ULONG_ZEROONE) goto err;
+        p[j] = val; /* restore the original value. */
+    }
+    return 0;
+
+err: /* memory error detected. */
+    p[j] = val;
+    return 1;
+}
+
 void memtest(size_t megabytes, int passes) {
     if (ioctl(1, TIOCGWINSZ, &ws) == -1) {
         ws.ws_col = 80;