Conform versioning of to uniform version standards

Library version will now only have major and minor. Package
version will now include number of commits since previous
package. Both SO and package versions rely on git tags to
determine the current build and the commits since the last
release.

Change-Id: If2bda74bf342930a9e07f5c91cb1380b6b7c64ca

cmake_modules/utils.cmake

@@ -73,10 +73,6 @@ function( parse_version VERSION_STRING )
         set ( TEMP_VERSION_STRING "${TEMP_VERSION_STRING}.${PATCH}" )
     endif ()
 
-    if ( DEFINED VERSION_BUILD )
-        set ( VERSION_BUILD "${VERSION_BUILD}" PARENT_SCOPE )
-    endif ()
-
     set ( VERSION_STRING "${TEMP_VERSION_STRING}" PARENT_SCOPE )
 
 endfunction ()
@@ -85,7 +81,7 @@ endfunction ()
 ## using versioning tags and git describe.
 ## Passes back a packaging version string
 ## and a library version string.
-function(get_version DEFAULT_VERSION_STRING VERSION_PREFIX)
+function(get_current_version DEFAULT_VERSION_STRING VERSION_PREFIX)
 
     parse_version ( ${DEFAULT_VERSION_STRING} )
 
@@ -109,7 +105,28 @@ function(get_version DEFAULT_VERSION_STRING VERSION_PREFIX)
     set( VERSION_STRING "${VERSION_STRING}" PARENT_SCOPE )
     set( VERSION_MAJOR  "${VERSION_MAJOR}" PARENT_SCOPE )
     set( VERSION_MINOR  "${VERSION_MINOR}" PARENT_SCOPE )
-    set( VERSION_PATCH  "${VERSION_PATCH}" PARENT_SCOPE )
-    set( VERSION_BUILD  "${VERSION_BUILD}" PARENT_SCOPE )
 
 endfunction()
+function(num_change_since_prev_pkg VERSION_PREFIX)
+
+    find_program(get_commits NAMES version_util.sh
+                 PATHS ${CMAKE_CURRENT_SOURCE_DIR}/cmake_modules)
+    if (get_commits)
+       execute_process( COMMAND ${get_commits} -c ${VERSION_PREFIX}
+                          WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
+                          OUTPUT_VARIABLE NUM_COMMITS
+                          OUTPUT_STRIP_TRAILING_WHITESPACE
+                          RESULT_VARIABLE RESULT )
+
+        set(NUM_COMMITS "${NUM_COMMITS}" PARENT_SCOPE )
+
+        if ( ${RESULT} EQUAL 0 )
+          message("${NUM_COMMITS} were found since previous release")
+        else()
+          message("Unable to determine number of commits since previous release")
+        endif()
+    else()
+        message("WARNING: Didn't find version_util.sh")
+        set(NUM_COMMITS "unknown" PARENT_SCOPE )
+    endif()
+endfunction()