Resurrect MQTT examples.

This refactored to put the cmake-include files in the library reactors, making them easier to use.
This also updated the docs and the installation instructions.

examples/C/src/mqtt/MQTTDistributed.lf

@@ -12,7 +12,7 @@
  * The code generator produces three programs, bin/MQTTDistributed_RTI, bin/MQTTDistributed_source,
  * and bin/MQTTDistributed_destination, plus a script bin/MQTTDistributed that runs all three.
  *
- * Since the source and destination are running in the same executable, there is no clock
+ * If the source and destination are running in the same machine, there is no clock
  * synchronization error.
  *
  * See README.md for prerequisites and further information.
@@ -21,7 +21,6 @@
  * @author Edward A. Lee
  */
 target C {
-  cmake-include: ["include/paho-extension.cmake", "include/mosquitto-extension.cmake"],
   timeout: 10 secs,
   coordination: centralized
 }

examples/C/src/mqtt/MQTTDistributedActivity.lf

@@ -11,7 +11,6 @@
  * @author Edward A. Lee
  */
 target C {
-  cmake-include: ["include/paho-extension.cmake", "include/mosquitto-extension.cmake"],
   timeout: 10 secs,
   coordination: centralized
 }

examples/C/src/mqtt/MQTTLegacy.lf

@@ -13,18 +13,13 @@
  *
  * This is a federated program, the publisher and subscriber run in separate programs. This would
  * work pretty much the same way, however, as an unfederated program. To run as an unfederated
- * program, add to cmake-include the following file:
- *
- * "include/net_utils.cmake"
- *
- * and change the `federated` keyword to `main`.
+ * program, just change the `federated` keyword to `main`.
  *
  * See README.md for prerequisites and further information.
  *
  * @author Edward A. Lee
  */
 target C {
-  cmake-include: ["include/paho-extension.cmake", "include/mosquitto-extension.cmake"],
   timeout: 1 min,
   coordination: centralized
 }
@@ -49,7 +44,7 @@ reactor Subscriber {
   sub.message -> dsp.message
 }
 
-federated reactor {
+main reactor {
   source = new Publisher()
   destination = new Subscriber()
 }

examples/C/src/mqtt/MQTTLogical.lf

@@ -13,10 +13,6 @@
  * @author Edward A. Lee
  */
 target C {
-  cmake-include: [
-      "include/paho-extension.cmake",  // For #include "MQTTClient.h"
-      // For encode_int64()
-      "include/net_utils.cmake"],
   timeout: 10 secs
 }
 

examples/C/src/mqtt/MQTTPhysical.lf

@@ -12,10 +12,6 @@
  * @author Edward A. Lee
  */
 target C {
-  cmake-include: [
-      "include/paho-extension.cmake",  // For #include "MQTTClient.h"
-      // For encode_int64() and extract_int64()
-      "include/net_utils.cmake"],
   timeout: 10 secs
 }
 

examples/C/src/mqtt/include/net_utils.cmake

@@ -1 +1 @@
-target_sources(${LF_MAIN_TARGET} PRIVATE "core/federated/net_util.c")
+target_sources(${LF_MAIN_TARGET} PRIVATE "core/federated/network/net_util.c")

examples/C/src/mqtt/lib/MQTTPublisher.lf

@@ -25,14 +25,18 @@
  * @author Ravi Akella
  * @author Edward A. Lee
  */
-target C
+target C {
+  cmake-include: [
+      "../include/paho-extension.cmake",
+      "../include/net_utils.cmake"  // For encode_int64()
+  ]
+}
 
 preamble {=
   #ifndef MQTT_PUBLISHER_H
   #define MQTT_PUBLISHER_H
 
   #include "platform.h" // Defines lf_critical_section_enter(), etc.
-  #include "tag.h"      // Defines lf_time_logical()
   #include <string.h>   // Defines memcpy
 
   #include "MQTTClient.h"

examples/C/src/mqtt/lib/MQTTSubscriber.lf

@@ -36,14 +36,18 @@
  * @author Ravi Akella
  * @author Edward A. Lee
  */
-target C
+target C {
+  cmake-include: [
+      "../include/paho-extension.cmake",
+      "../include/net_utils.cmake"  // For extract_int64()
+  ]
+}
 
 preamble {=
   #ifndef MQTT_SUBSCRIBER_H
   #define MQTT_SUBSCRIBER_H
 
   #include "platform.h" // Defines lf_critical_section_enter(), etc.
-  #include "tag.h"      // Defines lf_time_logical()
   #include <string.h>   // Defines memcmp()
 
   #include "MQTTClient.h"