lib: Reduce min keepalive to 2

This is the lowest value that produces a valid different int value when
multiplied by 3/2.

Speed up associated tests

include/mosquitto/libmosquitto_connect.h

@@ -56,7 +56,7 @@ extern "C" {
  * 	                   * mosq == NULL
  * 	                   * host == NULL
  * 	                   * port < 0
- * 	                   * keepalive < 5 (keepalive == 0 is allowed, for an infinite keepalive)
+ * 	                   * keepalive < 2 (keepalive == 0 is allowed, for an infinite keepalive)
  * 	MOSQ_ERR_ERRNO -   if a system call returned an error. The variable errno
  *                     contains the error code, even on Windows.
  *                     Use strerror_r() where available or FormatMessage() on

lib/connect.c

@@ -58,7 +58,7 @@ static int mosquitto__connect_init(struct mosquitto *mosq, const char *host, int
 	if(!host || port < 0 || port > UINT16_MAX){
 		return MOSQ_ERR_INVAL;
 	}
-	if(keepalive != 0 && (keepalive < 5 || keepalive > UINT16_MAX)){
+	if(keepalive != 0 && (keepalive < 2 || keepalive > UINT16_MAX)){
 		return MOSQ_ERR_INVAL;
 	}
 

test/lib/01-keepalive-pingreq.py

@@ -10,7 +10,7 @@
 from mosq_test_helper import *
 
 def do_test(conn, data):
-    keepalive = 5
+    keepalive = 2
     connect_packet = mqtt_packets.gen_connect("01-keepalive-pingreq", keepalive=keepalive)
     connack_packet = mqtt_packets.gen_connack(rc=0)
 
@@ -20,7 +20,6 @@ def do_test(conn, data):
     mosq_test.do_receive_send(conn, connect_packet, connack_packet, "connect")
 
     mosq_test.expect_packet(conn, "pingreq", pingreq_packet)
-    time.sleep(1.0)
     conn.send(pingresp_packet)
 
     mosq_test.expect_packet(conn, "pingreq", pingreq_packet)

test/lib/01-server-keepalive-pingreq.py

@@ -8,7 +8,7 @@ from mosq_test_helper import *
 
 def do_test(conn, data):
     keepalive = 60
-    server_keepalive = 4
+    server_keepalive = 2
     connect_packet = mqtt_packets.gen_connect("01-server-keepalive-pingreq", keepalive=keepalive, proto_ver=5)
 
     props = mqtt5_props.gen_uint16_prop(mqtt5_props.SERVER_KEEP_ALIVE, server_keepalive)
@@ -20,7 +20,6 @@ def do_test(conn, data):
     mosq_test.do_receive_send(conn, connect_packet, connack_packet, "connect")
 
     mosq_test.expect_packet(conn, "pingreq", pingreq_packet)
-    time.sleep(1.0)
     conn.send(pingresp_packet)
 
     mosq_test.expect_packet(conn, "pingreq", pingreq_packet)

test/lib/c/01-keepalive-pingreq.c

@@ -36,7 +36,7 @@ int main(int argc, char *argv[])
 	}
 	mosquitto_connect_callback_set(mosq, on_connect);
 
-	rc = mosquitto_connect(mosq, "localhost", port, 5);
+	rc = mosquitto_connect(mosq, "localhost", port, 2);
 	if(rc != MOSQ_ERR_SUCCESS){
 		return rc;
 	}

test/lib/cpp/01-keepalive-pingreq.cpp

@@ -37,7 +37,7 @@ int main(int argc, char *argv[])
 
 	mosq = new mosquittopp_test("01-keepalive-pingreq");
 
-	mosq->connect("localhost", port, 5);
+	mosq->connect("localhost", port, 2);
 
 	while(run == -1){
 		rc = mosq->loop();