Add a new command 'ctdb checktcpport <port>'

that tries to bind to the specified port on INADDR_ANY.

This can be used for testing if a service is listening to that port or not.

Errors are printed to stdout and the returned status code is either 0 : if we managed to bind to the port (in which case the service is NOT listening on that bort) or the value of errno that stopped us from binding to a port.

errno for EADDRINUSE is 98 so a script using this command should check the status code against the value 98.
If this command returns 98 it means the service is listening to the specified port.

(This used to be ctdb commit 04cbb490c5a075080923fde58af7082572c55c43)

1 files changed, 42 insertions, 0 deletions

diff --git a/ctdb/tools/ctdb.c b/ctdb/tools/ctdb.c
index 5618833160..d760f6bc77 100644
--- a/ctdb/tools/ctdb.c
+++ b/ctdb/tools/ctdb.c
@@ -3348,6 +3348,47 @@ static int control_pstore(struct ctdb_context *ctdb, int argc, const char **argv
 	return 0;
 }
 
+/*
+  check if a service is bound to a port or not
+ */
+static int control_chktcpport(struct ctdb_context *ctdb, int argc, const char **argv)
+{
+	int s, ret;
+	unsigned v;
+	int port;
+        struct sockaddr_in sin;
+
+	if (argc != 1) {
+		printf("Use: ctdb chktcport <port>\n");
+		return EINVAL;
+	}
+
+	port = atoi(argv[0]);
+
+	s = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
+	if (s == -1) {
+		printf("Failed to open local socket\n");
+		return errno;
+	}
+
+	v = fcntl(s, F_GETFL, 0);
+        fcntl(s, F_SETFL, v | O_NONBLOCK);
+
+	bzero(&sin, sizeof(sin));
+	sin.sin_family = PF_INET;
+	sin.sin_port   = htons(port);
+	ret = bind(s, (struct sockaddr *)&sin, sizeof(sin));
+	close(s);
+	if (ret == -1) {
+		printf("Failed to bind to local socket: %d %s\n", errno, strerror(errno));
+		return errno;
+	}
+
+	return 0;
+}
+
+
+
 static void log_handler(struct ctdb_context *ctdb, uint64_t srvid, 
 			     TDB_DATA data, void *private_data)
 {
@@ -4974,6 +5015,7 @@ static const struct {
 	{ "tfetch", 	     control_tfetch,      	false,	true,  "fetch a record from a [c]tdb-file", "<tdb-file> <key> [<file>]" },
 	{ "readkey", 	     control_readkey,      	true,	false,  "read the content off a database key", "<tdb-file> <key>" },
 	{ "writekey", 	     control_writekey,      	true,	false,  "write to a database key", "<tdb-file> <key> <value>" },
+	{ "checktcpport",    control_chktcpport,      	false,	true,  "check if a service is bound to a specific tcp port or not", "<port>" },
 };
 
 /*