test-tool/test_compareandwrite_*: Stop at end of medium

Since the argument num_blocks - i is passed as the LBA argument
to COMPAREANDWRITE(), avoid that a negative number is passed.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>

test-tool/test_compareandwrite_miscompare.c

@@ -31,7 +31,7 @@
 void
 test_compareandwrite_miscompare(void)
 {
-        int i;
+        int i, n;
         unsigned j;
         int maxbl;
 
@@ -44,10 +44,16 @@ test_compareandwrite_miscompare(void)
                 /* Assume we are not limited */
                 maxbl = 256;
         }
+
+        n = 256;
+        if (n + 0U > num_blocks)
+                n = num_blocks;
+
         logging(LOG_VERBOSE, LOG_BLANK_LINE);
-        logging(LOG_VERBOSE, "Test COMPARE_AND_WRITE of 1-256 blocks at the "
+        logging(LOG_VERBOSE, "Test COMPARE_AND_WRITE of 1-%d blocks at the "
-                "start of the LUN. One Byte miscompare in the final block.");
+                "start of the LUN. One Byte miscompare in the final block.",
-        for (i = 1; i < 256; i++) {
+                n);
+        for (i = 1; i <= n; i++) {
                 logging(LOG_VERBOSE, "Write %d blocks of 'A' at LBA:0", i);
                 memset(scratch, 'A', 2 * i * block_size);
                 if (maximum_transfer_length && maximum_transfer_length < i) {
@@ -98,9 +104,9 @@ test_compareandwrite_miscompare(void)
         }
 
 
-        logging(LOG_VERBOSE, "Test COMPARE_AND_WRITE of 1-256 blocks at the "
+        logging(LOG_VERBOSE, "Test COMPARE_AND_WRITE of 1-%d blocks at the "
-                "end of the LUN");
+                "end of the LUN", n);
-        for (i = 1; i < 256; i++) {
+        for (i = 1; i <= n; i++) {
                 logging(LOG_VERBOSE, "Write %d blocks of 'A' at LBA:%" PRIu64,
                         i, num_blocks - i);
                 memset(scratch, 'A', 2 * i * block_size);

test-tool/test_compareandwrite_simple.c

@@ -31,7 +31,7 @@
 void
 test_compareandwrite_simple(void)
 {
-        int i;
+        int i, n;
         unsigned j;
         int maxbl;
 
@@ -45,10 +45,14 @@ test_compareandwrite_simple(void)
                 maxbl = 256;
         }
 
+        n = 256;
+        if (n + 0U > num_blocks)
+                n = num_blocks;
+
         logging(LOG_VERBOSE, LOG_BLANK_LINE);
-        logging(LOG_VERBOSE, "Test COMPARE_AND_WRITE of 1-256 blocks at the "
+        logging(LOG_VERBOSE, "Test COMPARE_AND_WRITE of 1-%d blocks at the "
-                "start of the LUN");
+                "start of the LUN", n);
-        for (i = 1; i < 256; i++) {
+        for (i = 1; i <= n; i++) {
                 logging(LOG_VERBOSE, "Write %d blocks of 'A' at LBA:0", i);
                 memset(scratch, 'A', 2 * i * block_size);
                 if (maximum_transfer_length && maximum_transfer_length < i) {
@@ -97,9 +101,9 @@ test_compareandwrite_simple(void)
         }
 
 
-        logging(LOG_VERBOSE, "Test COMPARE_AND_WRITE of 1-256 blocks at the "
+        logging(LOG_VERBOSE, "Test COMPARE_AND_WRITE of 1-%d blocks at the "
-                "end of the LUN");
+                "end of the LUN", n);
-        for (i = 1; i < 256; i++) {
+        for (i = 1; i <= n; i++) {
                 logging(LOG_VERBOSE, "Write %d blocks of 'A' at LBA:%" PRIu64,
                         i, num_blocks - i);
                 memset(scratch, 'A', 2 * i * block_size);

test-tool/test_compareandwrite_unwritten.c

@@ -32,15 +32,19 @@
 void
 test_compareandwrite_unwritten(void)
 {
-	int i;
+	int i, n;
 
 	CHECK_FOR_DATALOSS;
 	CHECK_FOR_SBC;
 
+        n = 256;
+        if (n + 0U > num_blocks)
+                n = num_blocks;
+        
 	logging(LOG_VERBOSE, LOG_BLANK_LINE);
-	logging(LOG_VERBOSE, "Test COMPARE_AND_WRITE of 1-256 blocks at the "
+	logging(LOG_VERBOSE, "Test COMPARE_AND_WRITE of 1-%d blocks at the "
-		"start of the LUN, 1 block at a time");
+		"start of the LUN, 1 block at a time", n);
-	for (i = 1; i < 256; i++) {
+	for (i = 1; i <= n; i++) {
 		int caw_ret;
 		unsigned char read_buf[block_size];
 

test-tool/test_multipathio_compareandwrite.c

@@ -34,7 +34,7 @@ test_multipathio_compareandwrite(void)
 {
         int io_bl = 1;        /* 1 block CAW IOs */
         int path;
-        int i, ret;
+        int i, n, ret;
         int maxbl;
 
         CHECK_FOR_DATALOSS;
@@ -52,6 +52,10 @@ test_multipathio_compareandwrite(void)
                 return;
         }
 
+        n = 256;
+        if (n + 0U > num_blocks)
+                n = num_blocks;
+        
         logging(LOG_VERBOSE, LOG_BLANK_LINE);
         logging(LOG_VERBOSE, "Initialising data prior to COMPARE_AND_WRITE");
 
@@ -66,7 +70,7 @@ test_multipathio_compareandwrite(void)
         CU_ASSERT_EQUAL(ret, 0);
 
         logging(LOG_VERBOSE, "Test multipath COMPARE_AND_WRITE");
-        for (i = 0; i < 256; i++) {
+        for (i = 0; i <= n; i++) {
 
                 for (path = 0; path < mp_num_sds; path++) {
                         logging(LOG_VERBOSE,