Modifications to have parallel-installable gst-python

Original commit message from CVS:
* Makefile.am:
* configure.ac:
* gst/Makefile.am:
* pygst.py.in:
Modifications to have parallel-installable gst-python
Works more or less in the same way as pygtk:
import pygst
pygst.require('0.9')
import gst

ChangeLog

@@ -1,3 +1,16 @@
+2005-07-01  Edward Hervey  <edward@fluendo.com>
+
+	* Makefile.am:
+	* configure.ac:
+	* gst/Makefile.am:
+	* pygst.py.in:
+	Modifications to have parallel-installable gst-python
+	Works more or less in the same way as pygtk:
+	import pygst
+	pygst.require('0.9')
+	import gst
+	
+
 2005-06-28  Edward Hervey  <edward@fluendo.com>
 
 	* gst/pygstminiobject.c:

Makefile.am

@@ -18,3 +18,16 @@ EXTRA_DIST = \
 	RELEASE
 
 include $(top_srcdir)/common/release.mak
+
+# install pth file.
+install-data-local:
+	$(mkinstalldirs) $(DESTDIR)$(pythondir)
+	echo "gst-$(GST_MAJORMINOR)" > $(DESTDIR)$(pyexecdir)/pygst.pth
+install-exec-local:
+	$(mkinstalldirs) $(DESTDIR)$(pyexecdir)
+	echo "gst-$(GST_MAJORMINOR)" > $(DESTDIR)$(pyexecdir)/pygst.pth
+uninstall-local:
+	rm -f $(DESTDIR)$(pythondir)/pygst.pth $(DESTDIR)$(pyexecdir)/pygst.pth
+
+# this file is common to all pygtk versions.
+pyexec_PYTHON = pygst.py

common

@@ -1 +1 @@
-Subproject commit d6e46b214fac0ecb46010ff522af2f7653e1c18e
+Subproject commit 4ca96aedcf2be0b3dcf31fce732aed1da21b8850

configure.ac

@@ -160,6 +160,9 @@ fi
 PYGST_CFLAGS="$PYGST_ERROR_CFLAGS"
 AC_SUBST(PYGST_CFLAGS)
 
+dnl full installation path
+AS_AC_EXPAND(PYTHONDIR, $pythondir)
+
 dnl add debugging options ...
 changequote(,)dnl
 if test "x$GCC" = xyes; then
@@ -188,4 +191,5 @@ AC_OUTPUT([
   docs/gst-python.ent
   testsuite/Makefile
   gst-python.spec
+  pygst.py
 ])

gst/Makefile.am

@@ -2,8 +2,8 @@ common_cflags = $(PYGTK_CFLAGS) $(GST_CFLAGS) $(PYGST_CFLAGS) -fno-strict-aliasi
 common_libadd = $(GST_LIBS)
 common_ldflags = -module -avoid-version
 
-pkgpythondir = $(pythondir)/gst
-pkgpyexecdir = $(pyexecdir)/gst
+pkgpythondir = $(pythondir)/gst-$(GST_MAJORMINOR)/gst
+pkgpyexecdir = $(pyexecdir)/gst-$(GST_MAJORMINOR)/gst
 
 pygstdir = $(pkgpythondir)
 pygst_PYTHON = __init__.py

pygst.py.in

@@ -0,0 +1,57 @@
+# -*- Mode: Python; py-indent-offset: 4 -*-
+# pygtk - Python bindings for the GTK+ widget set.
+# Copyright (C) 1998-2002  James Henstridge
+#           (C) 2005 Edward Hervey
+#
+#   pygst.py: pygst version selection code.
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+# USA
+
+# This allows parallel installation of gst-python
+#
+# In order to have backward compatibility
+
+import fnmatch
+import glob
+import os
+import sys
+
+__all__ = ['require']
+
+_pygst_dir = '@PYTHONDIR@/gst-@GST_MAJORMINOR@'
+
+_pygst_version = '@GST_MAJORMINOR@'
+
+_pygst_required_version = None
+
+def require(version):
+    global _pygst_required_version
+
+    if _pygst_required_version != None:
+        assert _pygst_required_version == version, \
+               "a different version of gst was already required"
+        return
+
+    assert not sys.modules.has_key('gst'), \
+           "pygst.require() must be called before importing gst"
+
+    assert version == _pygst_version, \
+           "Only version '%s' is available" % version
+
+    # prepend the pygst path ...
+    sys.path.insert(0, _pygst_dir)
+    
+    _pygst_required_version = version