diff --git a/Modules/FindHg.cmake b/Modules/FindHg.cmake
index 8dea652328..c418afdd24 100644
--- a/Modules/FindHg.cmake
+++ b/Modules/FindHg.cmake
@@ -2,7 +2,7 @@
# FindHg
# ------
#
-#
+# Extract information from a mercurial working copy.
#
# The module defines the following variables:
#
@@ -12,6 +12,20 @@
# HG_FOUND - true if the command line client was found
# HG_VERSION_STRING - the version of mercurial found
#
+# If the command line client executable is found the following macro is defined:
+#
+# ::
+#
+# HG_WC_INFO(
)
+#
+# Hg_WC_INFO extracts information of a mercurial working copy
+# at a given location. This macro defines the following variables:
+#
+# ::
+#
+# _WC_CHANGESET - current changeset
+# _WC_REVISION - current revision
+#
# Example usage:
#
# ::
@@ -19,11 +33,15 @@
# find_package(Hg)
# if(HG_FOUND)
# message("hg found: ${HG_EXECUTABLE}")
+# HG_WC_INFO(${PROJECT_SOURCE_DIR} Project)
+# message("Current revision is ${Project_WC_REVISION}")
+# message("Current changeset is ${Project_WC_CHANGESET}")
# endif()
#=============================================================================
# Copyright 2010-2012 Kitware, Inc.
# Copyright 2012 Rolf Eike Beer
+# Copyright 2014 Matthaeus G. Chajdas
#
# Distributed under the OSI-approved BSD License (the "License");
# see accompanying file Copyright.txt for details.
@@ -53,6 +71,21 @@ if(HG_EXECUTABLE)
set(HG_VERSION_STRING "${CMAKE_MATCH_1}")
endif()
unset(hg_version)
+
+ macro(HG_WC_INFO dir prefix)
+ execute_process(COMMAND ${HG_EXECUTABLE} id -i -n
+ WORKING_DIRECTORY ${dir}
+ RESULT_VARIABLE hg_id_result
+ ERROR_VARIABLE hg_id_error
+ OUTPUT_VARIABLE ${prefix}_WC_DATA
+ OUTPUT_STRIP_TRAILING_WHITESPACE)
+ if(NOT ${hg_id_result} EQUAL 0)
+ message(SEND_ERROR "Command \"${HG_EXECUTBALE} id -n\" in directory ${dir} failed with output:\n${hg_id_error}")
+ endif()
+
+ string(REGEX REPLACE "([0-9a-f]+)\\+? [0-9]+\\+?" "\\1" ${prefix}_WC_CHANGESET ${${prefix}_WC_DATA})
+ string(REGEX REPLACE "[0-9a-f]+\\+? ([0-9]+)\\+?" "\\1" ${prefix}_WC_REVISION ${${prefix}_WC_DATA})
+ endmacro(HG_WC_INFO)
endif()
# Handle the QUIETLY and REQUIRED arguments and set HG_FOUND to TRUE if