generic/131: dynamically allocate tcp listen port to avoid port clashes

Current port selection algorithm is bound to have port clashes. To
eliminate clashes, let server pick an unused port and report it on
stdout.

Signed-off-by: Tahsin Erdogan <tahsin@google.com>
Reviewed-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Eryu Guan <eguan@redhat.com>

diff --git a/src/locktest.c b/src/locktest.c
index adf8ce05ccc5e7f28746e1cd5a75b60596a19a4a..eab48e2a012f71dd66ababe39f3b3bf51ff6e242 100644 (file)
--- a/src/locktest.c
+++ b/src/locktest.c
@@ -95,7 +95,7 @@ static char   *filename = 0;
 static int     debug = 0;
 static int     server = 1;
 static int     maxio = 8192;
-static int     port = 7890;
+static int     port = 0;
 static int     testnumber = -1;
 static int     saved_errno = 0;
 
@@ -899,6 +899,20 @@ main(int argc, char *argv[])
            /*NOTREACHED*/
        }
 
+       if (port == 0) {
+               socklen_t addr_len = sizeof(myAddr);
+
+               if (getsockname(s_fd, &myAddr, &addr_len)) {
+                   perror("getsockname");
+                   exit(1);
+               }
+
+               port = ntohs(myAddr.sin_port);
+       }
+
+       printf("server port: %d\n", port);
+       fflush(stdout);
+
        c_fd = accept(s_fd, NULL, NULL);
        if (c_fd == INVALID_SOCKET) {
            perror("accept");

diff --git a/tests/generic/131 b/tests/generic/131
index 3bcb0d16a34b2306156939d5941225bddd6918d5..d64ba550e258b3c0cddcef5e666a3ea0a8e79677 100755 (executable)
--- a/tests/generic/131
+++ b/tests/generic/131
@@ -49,21 +49,18 @@ _require_test_fcntl_advisory_locks
 
 TESTFILE=$TEST_DIR/lock_file
 
-# Grab a port which is hopefully unused
-if [ $$ -gt 1024 -a $$ -lt 32000 ]; then
-    PORT=$$
-elif [ $$ -lt 1024 ]; then
-    PORT=$(($$+1024))
-elif [ $$ -gt 32000 ]; then
-    PORT=$(($$%30000+1024))
-fi
-
 # Start the server
-src/locktest -p $PORT $TESTFILE 2>&1 > $TEST_DIR/server.out &
+src/locktest $TESTFILE 2>&1 > $TEST_DIR/server.out &
 locktest_pid1=$!
 
 sleep 1
 
+PORT=$(cat $TEST_DIR/server.out | grep "^server port: " | awk '{print $3}')
+if [ -z $PORT ]; then
+       echo "Could not get server port"
+       exit 1
+fi
+
 # Start the client
 src/locktest -p $PORT -h localhost $TESTFILE 2>&1 > $TEST_DIR/client.out
 locktest_pid2=$!