From: Robert Schwebel <r.schwebel@pengutronix.de>
Subject: add python path for cross compiling

When cross compiling dbus-python, we need to build a python for the
"build" machine and one for the "host" system. The current test for
python headers incorrectly grabs up the "build" headers, although this
package is built for the "host" machine.

This patch adds a "--with-python-includes=<path>" switch, which makes it
possible to overwrite the autodetected path with a pre-known one. Thus
it is possible for cross build systems like ptxdist, buildroot etc. to
set an already known path while cross compiling.

Signed-off-by: Robert Schwebel <r.schwebel@pengutronix.de>

---
 m4/am-check-python-headers.m4 |   38 +++++++++++++++++++++++---------------
 1 file changed, 23 insertions(+), 15 deletions(-)

Index: dbus-python-0.83.0/m4/am-check-python-headers.m4
===================================================================
--- dbus-python-0.83.0.orig/m4/am-check-python-headers.m4
+++ dbus-python-0.83.0/m4/am-check-python-headers.m4
@@ -5,21 +5,29 @@ AC_DEFUN([AM_CHECK_PYTHON_HEADERS],
 [AC_REQUIRE([AM_PATH_PYTHON])
 dnl deduce PYTHON_INCLUDES
 
-AC_MSG_CHECKING(for Python headers using $PYTHON-config --includes)
-PYTHON_INCLUDES=`$PYTHON-config --includes`
-if test $? = 0; then
-  AC_MSG_RESULT($PYTHON_INCLUDES)
-else
-  AC_MSG_RESULT([failed, will try another way])
-  py_prefix=`$PYTHON -c "import sys; print sys.prefix"`
-  py_exec_prefix=`$PYTHON -c "import sys; print sys.exec_prefix"`
-  AC_MSG_CHECKING(for Python headers in $py_prefix and $py_exec_prefix)
-  PYTHON_INCLUDES="-I${py_prefix}/include/python${PYTHON_VERSION}"
-  if test "$py_prefix" != "$py_exec_prefix"; then
-    PYTHON_INCLUDES="$PYTHON_INCLUDES -I${py_exec_prefix}/include/python${PYTHON_VERSION}"
-  fi
-  AC_MSG_RESULT($PYTHON_INCLUDES)
-fi
+AC_ARG_WITH(python_includes, AC_HELP_STRING(
+  [--with-python-includes], [set python include path manually]),
+  [
+    PYTHON_INCLUDES="-I${withval}/python${PYTHON_VERSION}"
+    AC_MSG_NOTICE([Using manually defined python include path])
+  ],[
+    AC_MSG_CHECKING(for Python headers using $PYTHON-config --includes)
+    PYTHON_INCLUDES=`$PYTHON-config --includes`
+    if test $? = 0; then
+      AC_MSG_RESULT($PYTHON_INCLUDES)
+    else
+      AC_MSG_RESULT([failed, will try another way])
+      py_prefix=`$PYTHON -c "import sys; print sys.prefix"`
+      py_exec_prefix=`$PYTHON -c "import sys; print sys.exec_prefix"`
+      AC_MSG_CHECKING(for Python headers in $py_prefix and $py_exec_prefix)
+      PYTHON_INCLUDES="-I${py_prefix}/include/python${PYTHON_VERSION}"
+      if test "$py_prefix" != "$py_exec_prefix"; then
+        PYTHON_INCLUDES="$PYTHON_INCLUDES -I${py_exec_prefix}/include/python${PYTHON_VERSION}"
+      fi
+      AC_MSG_RESULT($PYTHON_INCLUDES)
+    fi
+  ]
+)
 
 AC_MSG_CHECKING(whether those headers are sufficient)
 AC_SUBST(PYTHON_INCLUDES)