[glom] Fix the crash when calling python functions that return dates.

[Murray Cumming <murrayc src gnome org>]

commit bb9448a9b5d49704a008dd80f2defac081d935e7
Author: Murray Cumming <murrayc murrayc com>
Date:   Wed Dec 9 10:18:01 2009 +0100

    Fix the crash when calling python functions that return dates.
    
    * glom/libglom/python_embed/pygdavalue_conversions.c
    (glom_pygda_value_from_pyobject): Call the macro PyDateTime_IMPORT here,
    though it was already called in libglom_init(). I don't know why this
    fixes the crash, but it does. Bug #603686. (Andrew Ruthven)

 ChangeLog                                          |   11 ++++++++++-
 glom/libglom/python_embed/pygdavalue_conversions.c |    6 ++++++
 2 files changed, 16 insertions(+), 1 deletions(-)
---
diff --git a/ChangeLog b/ChangeLog
index 7101dcc..6e0aa02 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+2009-12-09  Murray Cumming  <murrayc murrayc com>
+
+	Fix the crash when calling python functions that return dates.
+
+	* glom/libglom/python_embed/pygdavalue_conversions.c
+	(glom_pygda_value_from_pyobject): Call the macro PyDateTime_IMPORT here, 
+	though it was already called in libglom_init(). I don't know why this 
+	fixes the crash, but it does. Bug #603686. (Andrew Ruthven)
+
 2009-12-08  Murray Cumming  <murrayc murrayc com>
 
 	Tests: Added glom_evaluate_python_function_implementation() tests.
@@ -6,7 +15,7 @@
 	* tests/test_python_execute_func.cc:
 	* tests/test_python_execute_func_date.cc: Added two unit tests for 
 	Glom::glom_evaluate_python_function_implementation(). The date one 
-	currently fails, as in bug #603686.
+	currently fails, as in bug #603686. (Andrew Ruthven)
 
 2009-12-07  Murray Cumming  <murrayc murrayc com>
 
diff --git a/glom/libglom/python_embed/pygdavalue_conversions.c b/glom/libglom/python_embed/pygdavalue_conversions.c
index 31d6609..521286d 100644
--- a/glom/libglom/python_embed/pygdavalue_conversions.c
+++ b/glom/libglom/python_embed/pygdavalue_conversions.c
@@ -19,6 +19,12 @@
 int
 glom_pygda_value_from_pyobject(GValue *boxed, PyObject *input)
 {
+    // We shouldn't need to call PyDateTime_IMPORT again, 
+    // after already doing it in libglom_init(),
+    // but PyDate_Check crashes (with valgrind warnings) if we don't.
+    PyDateTime_IMPORT; //A macro, needed to use PyDate_Check(), PyDateTime_Check(), etc.
+    g_assert(PyDateTimeAPI); //This should have been set by the PyDateTime_IMPORT macro.
+
     /* Use an appropriate gda_value_set_*() function.
        We can not know what GValue type is actually wanted, so
        we must still have the get_*() functions in the python API.