ENH: Find module for EXPAT library.

Modules/FindEXPAT.cmake

@@ -0,0 +1,38 @@
+# - Find expat
+# Find the native EXPAT headers and libraries.
+#
+#  EXPAT_INCLUDE_DIRS - where to find expat.h, etc.
+#  EXPAT_LIBRARIES    - List of libraries when using expat.
+#  EXPAT_FOUND        - True if expat found.
+
+# Look for the header file.
+FIND_PATH(EXPAT_INCLUDE_DIR NAMES expat.h)
+MARK_AS_ADVANCED(EXPAT_INCLUDE_DIR)
+
+# Look for the library.
+FIND_LIBRARY(EXPAT_LIBRARY NAMES expat)
+MARK_AS_ADVANCED(EXPAT_LIBRARY)
+
+# Copy the results to the output variables.
+IF(EXPAT_INCLUDE_DIR AND EXPAT_LIBRARY)
+  SET(EXPAT_FOUND 1)
+  SET(EXPAT_LIBRARIES ${EXPAT_LIBRARY})
+  SET(EXPAT_INCLUDE_DIRS ${EXPAT_INCLUDE_DIR})
+ELSE(EXPAT_INCLUDE_DIR AND EXPAT_LIBRARY)
+  SET(EXPAT_FOUND 0)
+  SET(EXPAT_LIBRARIES)
+  SET(EXPAT_INCLUDE_DIRS)
+ENDIF(EXPAT_INCLUDE_DIR AND EXPAT_LIBRARY)
+
+# Report the results.
+IF(NOT EXPAT_FOUND)
+  SET(EXPAT_DIR_MESSAGE
+    "EXPAT was not found. Make sure EXPAT_LIBRARY and EXPAT_INCLUDE_DIR are set.")
+  IF(NOT EXPAT_FIND_QUIETLY)
+    MESSAGE(STATUS "${EXPAT_DIR_MESSAGE}")
+  ELSE(NOT EXPAT_FIND_QUIETLY)
+    IF(EXPAT_FIND_REQUIRED)
+      MESSAGE(FATAL_ERROR "${EXPAT_DIR_MESSAGE}")
+    ENDIF(EXPAT_FIND_REQUIRED)
+  ENDIF(NOT EXPAT_FIND_QUIETLY)
+ENDIF(NOT EXPAT_FOUND)