From 3ad092ba09ef3c169a7a228c7030e316f8a3a635 Mon Sep 17 00:00:00 2001
From: Shahram Najm <masn@ecmwf.int>
Date: Sat, 17 Jan 2015 23:47:40 +0000
Subject: [PATCH] GRIB-672

---
 python/CMakeLists.txt | 45 +++++++++++++++++++++++++++++++------------
 1 file changed, 33 insertions(+), 12 deletions(-)

diff --git a/python/CMakeLists.txt b/python/CMakeLists.txt
index 584beb6d1..15804c984 100644
--- a/python/CMakeLists.txt
+++ b/python/CMakeLists.txt
@@ -2,19 +2,19 @@ if( HAVE_PYTHON )
 
     ecbuild_find_python( VERSION 2.5)
 
-    find_package( SWIG )
-    if( SWIG_FOUND )
-        include( ${SWIG_USE_FILE} )
-    endif()
+    #find_package( SWIG )
+    #if( SWIG_FOUND )
+    #    include( ${SWIG_USE_FILE} )
+    #endif()
 
     # check for Numpy
     find_package( NumPy )
 
-
     ###############################################################################
     # swig python interface
 
-    if( HAVE_PYTHON AND SWIG_FOUND AND PYTHONLIBS_FOUND )
+    #if( HAVE_PYTHON AND SWIG_FOUND AND PYTHONLIBS_FOUND )
+    if( HAVE_PYTHON AND PYTHONLIBS_FOUND )
 
         # preparing for generating setup.py -- this may not be needed as cmake can do the swig + shared libs without libtool
 
@@ -23,6 +23,8 @@ if( HAVE_PYTHON )
         else()
             set( DATA_HANDLER "array" )
         endif()
+        set( _swig_c_wrapper  swig_wrap_${DATA_HANDLER}.c )
+        set( _swig_py_wrapper swig_wrap_${DATA_HANDLER}.py )
 
         set( BUILD_DIR "${PROJECT_SOURCE_DIR}" ) # setup.py assumes build_dir is same as source_dir -- not true for cmake builds
 
@@ -50,14 +52,33 @@ if( HAVE_PYTHON )
 
         set_source_files_properties( gribapi_swig.i PROPERTIES C ON )
 
-        #if( NUMPY_FOUND )
-        #    set( CMAKE_SWIG_FLAGS "-DNUMPY" )
-        #    include_directories( ${NUMPY_INCLUDE_DIRS} )
-        #endif()
+        if( NUMPY_FOUND )
+            set( CMAKE_SWIG_FLAGS "-DNUMPY" )
+            include_directories( ${NUMPY_INCLUDE_DIRS} )
+        endif()
 
-        swig_add_module( gribapi_swig python grib_interface.h grib_interface.c gribapi_swig.i )
+        # Invoke swig to generate the C wrapper
+        #  swig_add_module( gribapi_swig python grib_interface.h grib_interface.c gribapi_swig.i )
+        #  swig_link_libraries( gribapi_swig grib_api ${PYTHON_LIBRARIES} )
 
-        swig_link_libraries( gribapi_swig grib_api ${PYTHON_LIBRARIES} )
+        ####### Do not invoke swig. Use our own generated C wrapper file ######
+        ecbuild_add_library(TARGET    _gribapi_swig
+                            TYPE SHARED
+                            NOINSTALL
+                            SOURCES   grib_interface.h grib_interface.c ${_swig_c_wrapper}
+                            LIBS      grib_api ${PYTHON_LIBRARIES} )
+        # Don't use the lib prefix.  This is needed for the python case where a _modulename.so is generated
+        set_target_properties(_gribapi_swig PROPERTIES PREFIX "")
+
+        # Copy the wrapper python file to build area
+        set( _swig_py  gribapi_swig.py )
+        add_custom_command(
+           OUTPUT ${_swig_py}
+           COMMAND ${CMAKE_COMMAND} -E copy ${CMAKE_CURRENT_SOURCE_DIR}/${_swig_py_wrapper} ${CMAKE_CURRENT_BINARY_DIR}/${_swig_py}
+           DEPENDS _gribapi_swig
+        )
+        add_custom_target(copy_swig_py ALL DEPENDS ${_swig_py})
+        #######################
 
         set(PYTHON_DEST "lib/python${PYTHON_VERSION_MAJOR}.${PYTHON_VERSION_MINOR}/site-packages/grib_api" )