Add ABI version handling in C code and Python code (#323)

* Add GPUARRAY_ABI_VERSION constant and
pygpu.gpuarray.abi_version() method.

A new header file (abi_version.h) auto-generated by CMake
has been added.

* Add auto-generated file `src/gpuarray/abi_version.h`
to .gitignore.

* Make GPUARRAY_ABI_VERSION a number (1000*major + minor)

Change ABI minor version (1.0 -> 1.1) to make some tests.

* Add auto-generated CMake SOVERSION variable
(equals to the first part of VERSION). Now
the built library file is named libgpuarray.so.SOVERSION,
that is libgpuarray.so.ABIMAJOR.

* Back to right current version.

Author: notoraptor

.gitignore

@@ -20,5 +20,6 @@ distribute*tar.gz
 pygpu/*.c
 pygpu/*.h
 pygpu/version.py
+src/gpuarray/abi_version.h
 src/private_config.h
 Makefile.conf

pygpu/gpuarray.pxd

@@ -23,6 +23,7 @@ cdef extern from "Python.h":
 
 cdef extern from "gpuarray/config.h":
     int GPUARRAY_API_VERSION
+    int GPUARRAY_ABI_VERSION
 
 cdef extern from "gpuarray/types.h":
     ctypedef struct gpuarray_type:

pygpu/gpuarray.pyx

@@ -13,6 +13,11 @@ def api_version():
     # (library version, module version)
     return (GPUARRAY_API_VERSION, 0)
 
+def abi_version():
+    major_version = GPUARRAY_ABI_VERSION / 1000
+    minor_version = GPUARRAY_ABI_VERSION % 1000
+    return (major_version, minor_version)
+
 np.import_array()
 
 # to export the numeric value

src/CMakeLists.txt

@@ -96,13 +96,27 @@ add_library(gpuarray-static STATIC ${GPUARRAY_SRC})
 target_link_libraries(gpuarray ${CMAKE_DL_LIBS})
 target_link_libraries(gpuarray-static ${CMAKE_DL_LIBS})
 
+# Generate gpuarray/abi_version.h that contains the ABI version number.
+get_target_property(GPUARRAY_ABI_VERSION gpuarray VERSION)
+string(REPLACE "." ";" GPUARRAY_ABI_VERSION_NUMBERS ${GPUARRAY_ABI_VERSION})
+list(GET GPUARRAY_ABI_VERSION_NUMBERS 0 GPUARRAY_ABI_VERSION_MAJOR)
+list(GET GPUARRAY_ABI_VERSION_NUMBERS 1 GPUARRAY_ABI_VERSION_MINOR)
+math(EXPR GPUARRAY_ABI_NUMBER "1000*${GPUARRAY_ABI_VERSION_MAJOR} + ${GPUARRAY_ABI_VERSION_MINOR}")
+FILE(WRITE gpuarray/abi_version.h
+"\#ifndef GPUARRAY_ABI_VERSION\n\#define GPUARRAY_ABI_VERSION ${GPUARRAY_ABI_NUMBER}\n\#endif\n"
+)
+
+# set SOVERSION and ensure it is the first part of VERSION.
+set_property(TARGET gpuarray PROPERTY SOVERSION ${GPUARRAY_ABI_VERSION_MAJOR})
+
 set(headers
   gpuarray/array.h
   gpuarray/blas.h
   gpuarray/collectives.h
   gpuarray/buffer.h
   gpuarray/buffer_blas.h
   gpuarray/buffer_collectives.h
+  gpuarray/abi_version.h
   gpuarray/config.h
   gpuarray/elemwise.h
   gpuarray/error.h

src/gpuarray/config.h

@@ -1,6 +1,8 @@
 #ifndef GPUARRAY_CONFIG
 #define GPUARRAY_CONFIG
 
+/* The following included file should have been generated by CMake. */
+#include <gpuarray/abi_version.h>
 #define GPUARRAY_API_VERSION 0
 
 #ifdef GPUARRAY_SHARED