Adds TCP_NODELAY as a runtime connect option

README.md

@@ -220,7 +220,7 @@ $ ctest -VV
 
 ### Cross compilation
 
-Cross compilation using CMake is performed by using so called "toolchain files" (see: http://www.vtk.org/Wiki/CMake_Cross_Compiling).
+Cross compilation using CMake is performed by using so called "toolchain files" (see: https://cmake.org/cmake/help/latest/manual/cmake-toolchains.7.html).
 
 The path to the toolchain file can be specified by using CMake's `-DCMAKE_TOOLCHAIN_FILE` option. In case no toolchain file is specified, the build is performed for the native build platform.
 
@@ -332,4 +332,3 @@ https://docs.microsoft.com/en-us/cpp/cpp/cdecl?view=vs-2019
 
 If you call this library from another language, you may need to take this into account.
 
-

src/Clients.h

@@ -157,6 +157,7 @@ typedef struct
 	MQTTClient_SSLOptions *sslopts; /**< the SSL/TLS connect options */
 	SSL_SESSION* session;           /**< SSL session pointer for fast handhake */
 #endif
+	int nodelay;					/**< TCP_NODELAY socket option */
 } Clients;
 
 int clientIDCompare(void* a, void* b);

src/MQTTAsync.c

@@ -562,7 +562,7 @@ int MQTTAsync_connect(MQTTAsync handle, const MQTTAsync_connectOptions* options)
 		goto exit;
 	}
 
-	if (strncmp(options->struct_id, "MQTC", 4) != 0 || options->struct_version < 0 || options->struct_version > 8)
+	if (strncmp(options->struct_id, "MQTC", 4) != 0 || options->struct_version < 0 || options->struct_version > 9)
 	{
 		rc = MQTTASYNC_BAD_STRUCTURE;
 		goto exit;
@@ -693,6 +693,10 @@ int MQTTAsync_connect(MQTTAsync handle, const MQTTAsync_connectOptions* options)
 		if (options->httpsProxy)
 			m->c->httpsProxy = MQTTStrdup(options->httpsProxy);
 	}
+	if (options->struct_version >= 9)
+		m->c->nodelay = options->nodelay;
+	else
+		m->c->nodelay = 0;
 
 	if (m->c->will)
 	{

src/MQTTAsync.h

@@ -1199,15 +1199,18 @@ typedef struct
 {
 	/** The eyecatcher for this structure.  must be MQTC. */
 	char struct_id[4];
-	/** The version number of this structure.  Must be 0, 1, 2, 3 4 5 6, 7 or 8.
+	/** The version number of this structure.  Must be 0, 1, 2, 3 4 5 6, 7,
+	  * 8, or 9.
+	  *
 	  * 0 signifies no SSL options and no serverURIs
 	  * 1 signifies no serverURIs
       * 2 signifies no MQTTVersion
       * 3 signifies no automatic reconnect options
       * 4 signifies no binary password option (just string)
       * 5 signifies no MQTTV5 properties
       * 6 signifies no HTTP headers option
-      * 7 signifies no HTTP proxy and HTTPS proxy options
+	  * 7 signifies no HTTP proxy and HTTPS proxy options
+	  * 8 signifies no TCP_NODELAY socket option
 	  */
 	int struct_version;
 	/** The "keep alive" interval, measured in seconds, defines the maximum time
@@ -1378,27 +1381,33 @@ typedef struct
 	 * HTTPS proxy
 	 */
 	const char* httpsProxy;
+	/**
+	 * Set the TCP_NODELAY option on the client socket. This could resuce
+	 * the latency on small messages as the cost of increased network
+	 * traffic.
+	 */
+	int nodelay;
 } MQTTAsync_connectOptions;
 
 /** Initializer for connect options for MQTT 3.1.1 non-WebSocket connections */
-#define MQTTAsync_connectOptions_initializer { {'M', 'Q', 'T', 'C'}, 8, 60, 1, 65535, NULL, NULL, NULL, 30, 0,\
-NULL, NULL, NULL, NULL, 0, NULL, MQTTVERSION_DEFAULT, 0, 1, 60, {0, NULL}, 0, NULL, NULL, NULL, NULL, NULL, NULL, NULL}
+#define MQTTAsync_connectOptions_initializer { {'M', 'Q', 'T', 'C'}, 9, 60, 1, 65535, NULL, NULL, NULL, 30, 0,\
+NULL, NULL, NULL, NULL, 0, NULL, MQTTVERSION_DEFAULT, 0, 1, 60, {0, NULL}, 0, NULL, NULL, NULL, NULL, NULL, NULL, NULL, 0}
 
 /** Initializer for connect options for MQTT 5.0 non-WebSocket connections */
-#define MQTTAsync_connectOptions_initializer5 { {'M', 'Q', 'T', 'C'}, 8, 60, 0, 65535, NULL, NULL, NULL, 30, 0,\
-NULL, NULL, NULL, NULL, 0, NULL, MQTTVERSION_5, 0, 1, 60, {0, NULL}, 1, NULL, NULL, NULL, NULL, NULL, NULL, NULL}
+#define MQTTAsync_connectOptions_initializer5 { {'M', 'Q', 'T', 'C'}, 9, 60, 0, 65535, NULL, NULL, NULL, 30, 0,\
+NULL, NULL, NULL, NULL, 0, NULL, MQTTVERSION_5, 0, 1, 60, {0, NULL}, 1, NULL, NULL, NULL, NULL, NULL, NULL, NULL, 0}
 
 /** Initializer for connect options for MQTT 3.1.1 WebSockets connections.
   * The keepalive interval is set to 45 seconds to avoid webserver 60 second inactivity timeouts.
   */
-#define MQTTAsync_connectOptions_initializer_ws { {'M', 'Q', 'T', 'C'}, 8, 45, 1, 65535, NULL, NULL, NULL, 30, 0,\
-NULL, NULL, NULL, NULL, 0, NULL, MQTTVERSION_DEFAULT, 0, 1, 60, {0, NULL}, 0, NULL, NULL, NULL, NULL, NULL, NULL, NULL}
+#define MQTTAsync_connectOptions_initializer_ws { {'M', 'Q', 'T', 'C'}, 9, 45, 1, 65535, NULL, NULL, NULL, 30, 0,\
+NULL, NULL, NULL, NULL, 0, NULL, MQTTVERSION_DEFAULT, 0, 1, 60, {0, NULL}, 0, NULL, NULL, NULL, NULL, NULL, NULL, NULL, 0}
 
 /** Initializer for connect options for MQTT 5.0 WebSockets connections.
   * The keepalive interval is set to 45 seconds to avoid webserver 60 second inactivity timeouts.
   */
-#define MQTTAsync_connectOptions_initializer5_ws { {'M', 'Q', 'T', 'C'}, 8, 45, 0, 65535, NULL, NULL, NULL, 30, 0,\
-NULL, NULL, NULL, NULL, 0, NULL, MQTTVERSION_5, 0, 1, 60, {0, NULL}, 1, NULL, NULL, NULL, NULL, NULL, NULL, NULL}
+#define MQTTAsync_connectOptions_initializer5_ws { {'M', 'Q', 'T', 'C'}, 9, 45, 0, 65535, NULL, NULL, NULL, 30, 0,\
+NULL, NULL, NULL, NULL, 0, NULL, MQTTVERSION_5, 0, 1, 60, {0, NULL}, 1, NULL, NULL, NULL, NULL, NULL, NULL, NULL, 0}
 
 
 /**

src/MQTTClient.c

@@ -1206,7 +1206,10 @@ static MQTTResponse MQTTClient_connectURIVersion(MQTTClient handle, MQTTClient_c
 	int sessionPresent = 0;
 	MQTTResponse resp = MQTTResponse_initializer;
 
+
 	FUNC_ENTRY;
+	m->c->nodelay =options->nodelay;
+
 	resp.reasonCode = SOCKET_ERROR;
 	if (m->ma && !running)
 	{
@@ -1759,7 +1762,7 @@ MQTTResponse MQTTClient_connectAll(MQTTClient handle, MQTTClient_connectOptions*
 		goto exit;
 	}
 
-	if (strncmp(options->struct_id, "MQTC", 4) != 0 || options->struct_version < 0 || options->struct_version > 8)
+	if (strncmp(options->struct_id, "MQTC", 4) != 0 || options->struct_version < 0 || options->struct_version > 9)
 	{
 		rc.reasonCode = MQTTCLIENT_BAD_STRUCTURE;
 		goto exit;

src/MQTTClient.h

@@ -825,7 +825,9 @@ typedef struct
 {
 	/** The eyecatcher for this structure.  must be MQTC. */
 	char struct_id[4];
-	/** The version number of this structure.  Must be 0, 1, 2, 3, 4, 5, 6, 7 or 8.
+	/** The version number of this structure.  Must be 0, 1, 2, 3, 4, 5, 6,
+	 *  7, 8, or 9.
+	 *
 	 * 0 signifies no SSL options and no serverURIs
 	 * 1 signifies no serverURIs
 	 * 2 signifies no MQTTVersion
@@ -834,6 +836,7 @@ typedef struct
 	 * 5 signifies no maxInflightMessages and cleanstart
 	 * 6 signifies no HTTP headers option
 	 * 7 signifies no HTTP proxy and HTTPS proxy options
+	 * 8 signifies no NO_DELAY
 	 */
 	int struct_version;
 	/** The "keep alive" interval, measured in seconds, defines the maximum time
@@ -976,27 +979,33 @@ typedef struct
 	 * HTTPS proxy
 	 */
 	const char* httpsProxy;
+	/**
+	 * Set the TCP_NODELAY option on the client socket. This could resuce
+	 * the latency on small messages as the cost of increased network
+	 * traffic.
+	 */
+	int nodelay;
 } MQTTClient_connectOptions;
 
 /** Initializer for connect options for MQTT 3.1.1 non-WebSocket connections */
-#define MQTTClient_connectOptions_initializer { {'M', 'Q', 'T', 'C'}, 8, 60, 1, 1, NULL, NULL, NULL, 30, 0, NULL,\
-0, NULL, MQTTVERSION_DEFAULT, {NULL, 0, 0}, {0, NULL}, -1, 0, NULL, NULL, NULL}
+#define MQTTClient_connectOptions_initializer { {'M', 'Q', 'T', 'C'}, 9, 60, 1, 1, NULL, NULL, NULL, 30, 0, NULL,\
+0, NULL, MQTTVERSION_DEFAULT, {NULL, 0, 0}, {0, NULL}, -1, 0, NULL, NULL, NULL, 0}
 
 /** Initializer for connect options for MQTT 5.0 non-WebSocket connections */
-#define MQTTClient_connectOptions_initializer5 { {'M', 'Q', 'T', 'C'}, 8, 60, 0, 1, NULL, NULL, NULL, 30, 0, NULL,\
-0, NULL, MQTTVERSION_5, {NULL, 0, 0}, {0, NULL}, -1, 1, NULL, NULL, NULL}
+#define MQTTClient_connectOptions_initializer5 { {'M', 'Q', 'T', 'C'}, 9, 60, 0, 1, NULL, NULL, NULL, 30, 0, NULL,\
+0, NULL, MQTTVERSION_5, {NULL, 0, 0}, {0, NULL}, -1, 1, NULL, NULL, NULL, 0}
 
 /** Initializer for connect options for MQTT 3.1.1 WebSockets connections.
   * The keepalive interval is set to 45 seconds to avoid webserver 60 second inactivity timeouts.
   */
-#define MQTTClient_connectOptions_initializer_ws { {'M', 'Q', 'T', 'C'}, 8, 45, 1, 1, NULL, NULL, NULL, 30, 0, NULL,\
-0, NULL, MQTTVERSION_DEFAULT, {NULL, 0, 0}, {0, NULL}, -1, 0, NULL, NULL, NULL}
+#define MQTTClient_connectOptions_initializer_ws { {'M', 'Q', 'T', 'C'}, 9, 45, 1, 1, NULL, NULL, NULL, 30, 0, NULL,\
+0, NULL, MQTTVERSION_DEFAULT, {NULL, 0, 0}, {0, NULL}, -1, 0, NULL, NULL, NULL, 0}
 
 /** Initializer for connect options for MQTT 5.0 WebSockets connections.
   * The keepalive interval is set to 45 seconds to avoid webserver 60 second inactivity timeouts.
   */
-#define MQTTClient_connectOptions_initializer5_ws { {'M', 'Q', 'T', 'C'}, 8, 45, 0, 1, NULL, NULL, NULL, 30, 0, NULL,\
-0, NULL, MQTTVERSION_5, {NULL, 0, 0}, {0, NULL}, -1, 1, NULL, NULL, NULL}
+#define MQTTClient_connectOptions_initializer5_ws { {'M', 'Q', 'T', 'C'}, 9, 45, 0, 1, NULL, NULL, NULL, 30, 0, NULL,\
+0, NULL, MQTTVERSION_5, {NULL, 0, 0}, {0, NULL}, -1, 1, NULL, NULL, NULL, 0}
 
 /**
   * This function attempts to connect a previously-created client (see

src/MQTTProtocolOut.c

@@ -265,9 +265,9 @@ int MQTTProtocol_connect(const char* ip_address, Clients* aClient, int websocket
 		if (timeout < 0)
 			rc = -1;
 		else
-			rc = Socket_new(aClient->net.http_proxy, addr_len, port, &(aClient->net.socket), timeout);
+			rc = Socket_new(aClient->net.http_proxy, addr_len, port, aClient->nodelay, &(aClient->net.socket), timeout);
 #else
-		rc = Socket_new(aClient->net.http_proxy, addr_len, port, &(aClient->net.socket));
+		rc = Socket_new(aClient->net.http_proxy, addr_len, port, aClient->nodelay, &(aClient->net.socket));
 #endif
 	}
 #if defined(OPENSSL)
@@ -277,9 +277,9 @@ int MQTTProtocol_connect(const char* ip_address, Clients* aClient, int websocket
 		if (timeout < 0)
 			rc = -1;
 		else
-			rc = Socket_new(aClient->net.https_proxy, addr_len, port, &(aClient->net.socket), timeout);
+			rc = Socket_new(aClient->net.https_proxy, addr_len, port, aClient->nodelay, &(aClient->net.socket), timeout);
 #else
-		rc = Socket_new(aClient->net.https_proxy, addr_len, port, &(aClient->net.socket));
+		rc = Socket_new(aClient->net.https_proxy, addr_len, port, aClient->nodelay, &(aClient->net.socket));
 #endif
 	}
 #endif
@@ -295,9 +295,9 @@ int MQTTProtocol_connect(const char* ip_address, Clients* aClient, int websocket
 		if (timeout < 0)
 			rc = -1;
 		else
-			rc = Socket_new(ip_address, addr_len, port, &(aClient->net.socket), timeout);
+			rc = Socket_new(ip_address, addr_len, port, aClient->nodelay, &(aClient->net.socket), timeout);
 #else
-		rc = Socket_new(ip_address, addr_len, port, &(aClient->net.socket));
+		rc = Socket_new(ip_address, addr_len, port, aClient->nodelay, &(aClient->net.socket));
 #endif
 	}
 	if (rc == EINPROGRESS || rc == EWOULDBLOCK)

src/Socket.c

@@ -44,6 +44,13 @@
 
 #include "Heap.h"
 
+#if defined(_WIN32) || defined(_WIN64)
+#define SOL_TCP IPPROTO_TCP
+#elif !defined(SOL_TCP) && defined(IPPROTO_TCP)
+#define SOL_TCP IPPROTO_TCP
+#endif
+
+
 #if defined(USE_SELECT)
 int isReady(int socket, fd_set* read_set, fd_set* write_set);
 int Socket_continueWrites(fd_set* pwset, SOCKET* socket, mutex_type mutex);
@@ -1049,9 +1056,9 @@ int Socket_close(SOCKET socket)
  *  @return completion code 0=good, SOCKET_ERROR=fail
  */
 #if defined(__GNUC__) && defined(__linux__)
-int Socket_new(const char* addr, size_t addr_len, int port, SOCKET* sock, long timeout)
+int Socket_new(const char* addr, size_t addr_len, int port, int nodelay, SOCKET* sock, long timeout)
 #else
-int Socket_new(const char* addr, size_t addr_len, int port, SOCKET* sock)
+int Socket_new(const char* addr, size_t addr_len, int port, int nodelay, SOCKET* sock)
 #endif
 {
 	int type = SOCK_STREAM;
@@ -1181,6 +1188,13 @@ int Socket_new(const char* addr, size_t addr_len, int port, SOCKET* sock)
 						Log(LOG_ERROR, -1, "Could not set SO_SNDBUF for socket %d", *sock);
 				}
 #endif
+			if (nodelay)
+			{
+				int opt = 1;
+				if (setsockopt(*sock, SOL_TCP, TCP_NODELAY, &opt, sizeof(opt)) != 0)
+					Log(LOG_ERROR, -1, "Could not set TCP_NODELAY for socket %d", *sock);
+
+			}
 			Log(TRACE_MIN, -1, "New socket %d for %s, port %d",	*sock, addr, port);
 			if (Socket_addSocket(*sock) == SOCKET_ERROR)
 				rc = Socket_error("addSocket", *sock);

src/Socket.h

@@ -145,9 +145,9 @@ int Socket_putdatas(SOCKET socket, char* buf0, size_t buf0len, PacketBuffers buf
 int Socket_close(SOCKET socket);
 #if defined(__GNUC__) && defined(__linux__)
 /* able to use GNU's getaddrinfo_a to make timeouts possible */
-int Socket_new(const char* addr, size_t addr_len, int port, SOCKET* socket, long timeout);
+int Socket_new(const char* addr, size_t addr_len, int port, int nodelay, SOCKET* socket, long timeout);
 #else
-int Socket_new(const char* addr, size_t addr_len, int port, SOCKET* socket);
+int Socket_new(const char* addr, size_t addr_len, int port, int nodelay, SOCKET* socket);
 #endif
 
 int Socket_noPendingWrites(SOCKET socket);

test/test1.c

@@ -1168,10 +1168,85 @@ int test6a(struct Options options)
 	return failures;
 }
 
+/*********************************************************************
+
+Test7: Socket options
+
+*********************************************************************/
+
+int test7(struct Options options)
+{
+	MQTTClient c;
+	MQTTClient_connectOptions opts = MQTTClient_connectOptions_initializer;
+	MQTTClient_willOptions wopts = MQTTClient_willOptions_initializer;
+	int rc = 0;
+	char* test_topic = "C client test7";
+
+	fprintf(xml, "<testcase classname=\"test1\" name=\"socket options\"");
+	global_start_time = start_clock();
+	failures = 0;
+	MyLog(LOGA_INFO, "Starting test 7 - socket options");
+
+	rc = MQTTClient_create(&c, options.connection, "sockopt_test",
+			MQTTCLIENT_PERSISTENCE_DEFAULT, NULL);
+	assert("good rc from create",  rc == MQTTCLIENT_SUCCESS, "rc was %d\n", rc);
+	if (rc != MQTTCLIENT_SUCCESS)
+	{
+		MQTTClient_destroy(&c);
+		goto exit;
+	}
+
+	opts.keepAliveInterval = 20;
+	opts.cleansession = 1;
+	opts.username = "testuser";
+	opts.password = "testpassword";
+	opts.MQTTVersion = options.MQTTVersion;
+	if (options.haconnections != NULL)
+	{
+		opts.serverURIs = options.haconnections;
+		opts.serverURIcount = options.hacount;
+	}
+
+	opts.will = &wopts;
+	opts.will->message = "will message";
+	opts.will->qos = 1;
+	opts.will->retained = 0;
+	opts.will->topicName = "will topic";
+	opts.will = NULL;
+
+	opts.nodelay = 1;
+
+	/* Test with the socket option(s) */
+	MyLog(LOGA_DEBUG, "Connecting");
+	rc = MQTTClient_connect(c, &opts);
+	assert("Good rc from connect", rc == MQTTCLIENT_SUCCESS, "rc was %d", rc);
+	if (rc != MQTTCLIENT_SUCCESS)
+		goto exit;
+
+	rc = MQTTClient_disconnect(c, 0);
+	assert("Disconnect successful", rc == MQTTCLIENT_SUCCESS, "rc was %d", rc);
+
+	/* Try to reconnect */
+	rc = MQTTClient_connect(c, &opts);
+	assert("Connect successful",  rc == MQTTCLIENT_SUCCESS, "rc was %d", rc);
+
+	rc = MQTTClient_disconnect(c, 0);
+	assert("Disconnect successful", rc == MQTTCLIENT_SUCCESS, "rc was %d", rc);
+
+	MQTTClient_destroy(&c);
+
+exit:
+	MyLog(LOGA_INFO, "TEST1: test %s. %d tests run, %d failures.",
+			(failures == 0) ? "passed" : "failed", tests, failures);
+	write_test_result();
+	return failures;
+}
+
+
 int main(int argc, char** argv)
 {
 	int rc = 0;
- 	int (*tests[])() = {NULL, test1, test2, test3, test4, test5, test6, test6a};
+ 	int (*tests[])() = {NULL, test1, test2, test3, test4, test5, test6, test6a, test7};
 	int i;
 
 	xml = fopen("TEST-test1.xml", "w");