--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/cmake/FindVersion.cmake	Thu Jan 15 21:33:54 2009 +0200
@@ -0,0 +1,48 @@
+#
+# CMake build script to determine project version number.
+#
+# this will set PROJECT_VERSION to a string
+#
+FUNCTION (FindProjectVersion project_path)
+    # XXX: only support mercurial for now
+
+    MESSAGE (STATUS "project_path=${project_path}")
+
+    # first, determine tag
+    EXECUTE_PROCESS (
+        COMMAND hg identify --tag
+        WORKING_DIRECTORY "${project_path}"
+        RESULT_VARIABLE hg_error_code 
+        OUTPUT_VARIABLE hg_tag
+        OUTPUT_STRIP_TRAILING_WHITESPACE
+    )
+    
+    if (hg_error_code)
+        MESSAGE (FATAL_ERROR "`hg identify --tag` failed")
+    endif (hg_error_code)
+
+    # if tag is other than tip, use that
+    if ("${hg_tag}" STREQUAL "tip")
+        # use the revision hash
+        EXECUTE_PROCESS (
+            COMMAND hg identify --id
+            WORKING_DIRECTORY "${project_path}"
+            RESULT_VARIABLE hg_error_code 
+            OUTPUT_VARIABLE hg_id
+            OUTPUT_STRIP_TRAILING_WHITESPACE
+        )
+
+        if (hg_error_code)
+            MESSAGE (FATAL_ERROR "`hg identify --id` failed")
+        endif (hg_error_code)
+
+        SET (PROJECT_VERSION "${hg_id}" PARENT_SCOPE)
+        MESSAGE (STATUS "Version: mercurial tip id: ${hg_id}")
+
+    else ("${hg_tag}" STREQUAL "tip")
+        SET (PROJECT_VERSION "${hg_tag}" PARENT_SCOPE)
+        MESSAGE (STATUS "Version: mercurial tag: ${hg_tag}")
+
+    endif ("${hg_tag}" STREQUAL "tip")
+
+ENDFUNCTION (FindProjectVersion)