microbit: Updates to enable semantic versioning of the micro:bit runtime DAL

More specifically, the build system now uses the semantic versioning meta-data
held in module.json to define a major.minor.patch version. Additionally, is the branch
being compiled is *not* the master branch, the version is appended with <branchname><githash>.

Specific updates:

- Updates to CMake files to expose this to the micro:bit runtime code.
- Addition of uBit.systemVersion() to expose this to application code.
- Displaying of version string over serial if MICROBIT_DBG is enabled.
- Distribution of version string over BLE via the firmware revision characteristic.

inc/MicroBit.h

@@ -225,6 +225,14 @@ class MicroBit
       */
     unsigned long systemTime();
     
+    /**
+      * Determine the version of the micro:bit runtime currently in use.
+      *
+      * @return A textual description of the currentlt executing micro:bit runtime.
+      * TODO: handle overflow case.
+      */
+    char *systemVersion();
+
     /**
       * Triggers a microbit panic where an infinite loop will occur swapping between the panicFace and statusCode if provided.
       * 

inc/MicroBitConfig.h

@@ -243,6 +243,16 @@
 #define MICROBIT_HEAP_DBG       0
 #endif
 
+// Versioning options.
+// We use semantic versioning (http://semver.org/) to identify differnet versions of the micro:bit runtime.
+// Where possible we use yotta (an ARM mbed build tool) to help us track versions.
+// if this isn't available, it can be defined manually as a configuration option.
+//
+#ifndef MICROBIT_DAL_VERSION
+#define MICROBIT_DAL_VERSION   "unknown" 
+#endif
+
+
 //
 // Helper macro used by the micro:bit runtime to determine if a boolean configuration option is set.
 //

module.json

@@ -1,10 +1,10 @@
 {
   "name": "microbit-dal",
-  "version": "0.0.1",
+  "version": "1.2.1",
   "license": "Apache2",
   "description": "The runtime library for the BBC micro:bit, developed by Lancaster University",
   "keywords": ["mbed-classic", "microbit", "runtime", "library", "lancaster", "University"],
-  "author": "James Devine <j.devine@lancaster.ac.uk (mailto:j.devine@lancaster.ac.uk) >",
+  "author": "Joe Finney <j.finney@lancaster.ac.uk (mailto:j.finney@lancaster.ac.uk) >",
   "homepage": "https://developer.mbed.org/teams/Lancaster-University/code/microbit/",
   "dependencies":{
     "mbed-classic": "~0.0.4",

source/CMakeLists.txt

@@ -32,10 +32,24 @@ set(YOTTA_AUTO_MICROBIT-DAL_CPP_FILES
     "MemberFunctionCallback.cpp"
 )
 
+execute_process(WORKING_DIRECTORY "../../yotta_modules/${PROJECT_NAME}" COMMAND "git" "log" "--pretty=format:%h" "-n" "1" OUTPUT_VARIABLE git_hash)
+execute_process(WORKING_DIRECTORY "../../yotta_modules/${PROJECT_NAME}" COMMAND "git" "rev-parse" "--abbrev-ref" "HEAD" OUTPUT_VARIABLE git_branch OUTPUT_STRIP_TRAILING_WHITESPACE)
+
+if (${git_branch} STREQUAL "master")
+    set(MICROBIT_DAL_VERSION_STRING "${YOTTA_MICROBIT_DAL_VERSION_STRING}")
+else()
+    set(MICROBIT_DAL_VERSION_STRING "${YOTTA_MICROBIT_DAL_VERSION_STRING}-${git_branch}-g${git_hash}")
+endif()
+
+set(MICROBIT_DAL_VERSION_FLAGS "-DMICROBIT_DAL_VERSION=\\\"${MICROBIT_DAL_VERSION_STRING}\\\"")
+
+set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${MICROBIT_DAL_VERSION_FLAGS}")
+
 if (YOTTA_CFG_MICROBIT_CONFIGFILE)
     set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${YOTTA_FORCE_INCLUDE_FLAG} \"${YOTTA_CFG_MICROBIT_CONFIGFILE}\"")
 endif ()
 
+
 if(CMAKE_COMPILER_IS_GNUCC)
   file(REMOVE "CortexContextSwitch.s")
   configure_file("CortexContextSwitch.s.gcc" "CortexContextSwitch.s" COPYONLY)

source/MicroBit.cpp

@@ -4,10 +4,10 @@ char MICROBIT_BLE_DEVICE_NAME[] = "BBC MicroBit [xxxxx]";
 
 #if CONFIG_ENABLED(MICROBIT_BLE_ENABLED) && CONFIG_ENABLED(MICROBIT_BLE_DEVICE_INFORMATION_SERVICE)
 const char MICROBIT_BLE_MANUFACTURER[] = "The Cast of W1A";
-const char MICROBIT_BLE_MODEL[] = "Microbit SB2";
+const char MICROBIT_BLE_MODEL[] = "micro:bit";
 const char MICROBIT_BLE_SERIAL[] = "SN1";
 const char MICROBIT_BLE_HARDWARE_VERSION[] = "0.2";
-const char MICROBIT_BLE_FIRMWARE_VERSION[] = "1.1";
+const char MICROBIT_BLE_FIRMWARE_VERSION[] = MICROBIT_DAL_VERSION;
 const char MICROBIT_BLE_SOFTWARE_VERSION[] = "1.0";
 #endif
 
@@ -340,7 +340,7 @@ void MicroBit::removeIdleComponent(MicroBitComponent *component)
 {
     int i = 0;
     
-    while(idleThreadComponents[i] != component  && i < MICROBIT_IDLE_COMPONENTS)  
+    while(idleThreadComponents[i] != component && i < MICROBIT_IDLE_COMPONENTS)  
         i++;
     
     if(i == MICROBIT_IDLE_COMPONENTS)
@@ -360,6 +360,18 @@ unsigned long MicroBit::systemTime()
     return ticks;
 }
 
+
+/**
+ * Determine the version of the micro:bit runtime currently in use.
+ *
+ * @return A textual description of the currentlt executing micro:bit runtime.
+ * TODO: handle overflow case.
+ */
+char *MicroBit::systemVersion()
+{
+    return MICROBIT_DAL_VERSION;
+}
+
 /**
   * Triggers a microbit panic where an infinite loop will occur swapping between the panicFace and statusCode if provided.
   * 

source/MicroBitSuperMain.cpp

@@ -16,12 +16,16 @@ int main()
 #if CONFIG_ENABLED(MICROBIT_DBG)
     pc.baud(115200);
 
+
     // For diagnostics. Gives time to open the console window. :-) 
     for (int i=3; i>0; i--)
     {
         pc.printf("=== SUPERMAIN: Starting in %d ===\n", i);
         wait(1.0);
     }
+
+    pc.printf("micro:bit runtime DAL version %s\n", MICROBIT_DAL_VERSION);
+
 #endif    
 
     // Bring up our nested heap allocator.