build,python: Support building Python bindings as nested package

* autogen-all.sh (packages): Add lang/python.
* configure.ac: Add python to available languages if subdir exists. Add
python to nested languages if enabled to generate corresponding make
targets. Call configure script of nested python package recursively.
* lang/python/configure.ac: Check if Python bindings are built as
nested package and set GPGME_CFLAGS and GPGME_LIBS accordingly.
* lang/python/setup.py.in: Define some variables where they are used
first. Extract library directories from GPGME_LIBS variable similar
to the extraction of include directories from GPGME_CFLAGS. Adjust
library locations in case of win32 the same way as the include
locations. Prefer gpgme.h in the include directories from GPGME_CFLAGS
over the one in the prefix, so that the correct gpgme.h is taken in
case of nested builds.
--

This re-adds the ability to build the Python bindings together with
gpgme with a single `configure && make` command (if building from git).

GnuPG-bug-id: 7110

1 files changed, 20 insertions, 2 deletions

diff --git a/lang/python/configure.ac b/lang/python/configure.ac
index 34033ed3..116d7d0b 100644
--- a/lang/python/configure.ac
+++ b/lang/python/configure.ac
@@ -409,8 +409,26 @@ AM_CONDITIONAL(USE_GPGRT_CONFIG, [test -n "$GPGRT_CONFIG" \
 
 # And for gpgme.
 have_gpgme=no
-AM_PATH_GPGME("$NEED_GPGME_VERSION",
-              have_gpgme=yes, have_gpgme=no)
+builddir=`pwd`
+# Check if Python bindings are built as nested package of gpgme
+if test "${srcdir%/lang/python}/lang/python" == "$srcdir" -a \
+        "${builddir%/lang/python}/lang/python" == "$builddir"; then
+  AC_MSG_CHECKING(for GpgME - assuming nested build)
+  gpgme_build_dir=${builddir%/lang/python}
+  if test -f "$gpgme_build_dir/src/gpgme.h"; then
+    GPGME_CFLAGS="-I$gpgme_build_dir/src"
+    GPGME_LIBS="-L$gpgme_build_dir/src/.libs -lgpgme"
+    have_gpgme=yes
+    AC_MSG_RESULT(yes)
+  else
+    AC_MSG_RESULT(no)
+  fi
+fi
+
+if test "$have_gpgme" = "no"; then
+  AM_PATH_GPGME("$NEED_GPGME_VERSION",
+                have_gpgme=yes, have_gpgme=no)
+fi
 
 
 #