[pygobject] Remove and deprecate API for setting of thread blocking functions

[Simon Feltman <sfeltman src gnome org>]

commit c9e95663d05de98a9abd3d1479554b1f09753382
Author: Simon Feltman <sfeltman src gnome org>
Date:   Thu May 2 03:57:05 2013 -0700

    Remove and deprecate API for setting of thread blocking functions
    
    Remove pyglib_set_thread_block_funcs and deprecate pyg_set_thread_block_funcs.
    The thread block function APIs are no longer be neccessary because PyGObject
    can use the Python C API directly when working with threads.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=699440

 gi/_glib/pyglib.c               |   41 ---------------------------------
 gi/_glib/pyglib.h               |    9 ++++---
 gi/_gobject/gobjectmodule.c     |   25 +++++++-------------
 gi/_gobject/pygobject-private.h |   33 --------------------------
 gi/_gobject/pygobject.h         |   48 ++++++++++++++++++--------------------
 gi/gimodule.c                   |   15 +++++++-----
 6 files changed, 46 insertions(+), 125 deletions(-)
---
diff --git a/gi/_glib/pyglib.c b/gi/_glib/pyglib.c
index 54b2d90..9753a52 100644
--- a/gi/_glib/pyglib.c
+++ b/gi/_glib/pyglib.c
@@ -77,47 +77,6 @@ pyglib_init_internal(PyObject *api)
 }
 
 /**
- * pyglib_block_threads:
- *
- */
-void
-pyglib_block_threads(void)
-{
-    g_return_if_fail (_PyGLib_API != NULL);
-
-    if (_PyGLib_API->block_threads != NULL)
-       (* _PyGLib_API->block_threads)();
-}
-
-/**
- * pyglib_unblock_threads:
- *
- */
-void
-pyglib_unblock_threads(void)
-{
-    g_return_if_fail (_PyGLib_API != NULL);
-    if (_PyGLib_API->unblock_threads != NULL)
-       (* _PyGLib_API->unblock_threads)();
-}
-
-/**
- * pyglib_set_thread_block_funcs:
- *
- * hooks to register handlers for getting GDK threads to cooperate
- * with python threading
- */
-void
-pyglib_set_thread_block_funcs (PyGLibThreadBlockFunc block_threads_func,
-                              PyGLibThreadBlockFunc unblock_threads_func)
-{
-    g_return_if_fail (_PyGLib_API != NULL);
-
-    _PyGLib_API->block_threads = block_threads_func;
-    _PyGLib_API->unblock_threads = unblock_threads_func;
-}
-
-/**
  * pyglib_error_marshal:
  * @error: a pointer to the GError.
  *
diff --git a/gi/_glib/pyglib.h b/gi/_glib/pyglib.h
index 0b587b8..35be4eb 100644
--- a/gi/_glib/pyglib.h
+++ b/gi/_glib/pyglib.h
@@ -46,15 +46,16 @@ void pyglib_init_internal(PyObject *api);
 #    define pyglib_end_allow_threads         Py_END_ALLOW_THREADS
 #endif
 
+/* Deprecated, only available for API compatibility. */
+#define pyg_set_thread_block_funcs(a, b)
+#define pyglib_block_threads()
+#define pyglib_unblock_threads()
+
 gboolean pyglib_error_check(GError **error);
 PyObject *pyglib_error_marshal (GError **error);
 gboolean pyglib_gerror_exception_check(GError **error);
 PyObject *pyglib_register_exception_for_domain(gchar *name,
                                               gint error_domain);
-void pyglib_set_thread_block_funcs(PyGLibThreadBlockFunc block_threads_func,
-                                  PyGLibThreadBlockFunc unblock_threads_func);
-void pyglib_block_threads(void);
-void pyglib_unblock_threads(void);
 PyObject * pyglib_option_context_new(GOptionContext *context);
 PyObject * pyglib_option_group_new(GOptionGroup *group);
 GOptionGroup * pyglib_option_group_transfer_group(PyObject *self);
diff --git a/gi/_gobject/gobjectmodule.c b/gi/_gobject/gobjectmodule.c
index 3de839d..1e1cbd8 100644
--- a/gi/_gobject/gobjectmodule.c
+++ b/gi/_gobject/gobjectmodule.c
@@ -48,24 +48,17 @@ static void pyg_flags_add_constants(PyObject *module, GType flags_type,
 
 /**
  * pyg_set_thread_block_funcs:
- * @block_threads_func: a function to block Python threads.
- * @unblock_threads_func: a function to unblock Python threads.
- *
- * an interface to allow pygtk to add hooks to handle threading
- * similar to the old PyGTK 0.6.x releases.  May not work quite right
- * anymore.
+ * Deprecated, only available for ABI compatibility.
  */
 static void
-pyg_set_thread_block_funcs (PyGThreadBlockFunc block_threads_func,
-                           PyGThreadBlockFunc unblock_threads_func)
+_pyg_set_thread_block_funcs (PyGThreadBlockFunc block_threads_func,
+                            PyGThreadBlockFunc unblock_threads_func)
 {
-    g_return_if_fail(pygobject_api_functions.block_threads == NULL &&
-                    pygobject_api_functions.unblock_threads == NULL);
-
-    pygobject_api_functions.block_threads   = block_threads_func;
-    pygobject_api_functions.unblock_threads = unblock_threads_func;
-    pyglib_set_thread_block_funcs(block_threads_func,
-                                 unblock_threads_func);
+    PyGILState_STATE state = pyglib_gil_state_ensure ();
+    PyErr_Warn (PyExc_DeprecationWarning,
+                "Using pyg_set_thread_block_funcs is not longer needed. "
+                "PyGObject always uses Py_BLOCK/UNBLOCK_THREADS.");
+    pyglib_gil_state_release (state);
 }
 
 /**
@@ -2031,7 +2024,7 @@ struct _PyGObject_Functions pygobject_api_functions = {
 
   pyg_error_check,
 
-  pyg_set_thread_block_funcs,
+  _pyg_set_thread_block_funcs,
   (PyGThreadBlockFunc)0, /* block_threads */
   (PyGThreadBlockFunc)0, /* unblock_threads */
 
diff --git a/gi/_gobject/pygobject-private.h b/gi/_gobject/pygobject-private.h
index 5de7488..e2a0af7 100644
--- a/gi/_gobject/pygobject-private.h
+++ b/gi/_gobject/pygobject-private.h
@@ -21,39 +21,6 @@
 
 /* from gobjectmodule.c */
 extern struct _PyGObject_Functions pygobject_api_functions;
-#define pyg_block_threads()   G_STMT_START { \
-    if (pygobject_api_functions.block_threads != NULL)    \
-      (* pygobject_api_functions.block_threads)();        \
-  } G_STMT_END
-#define pyg_unblock_threads() G_STMT_START { \
-    if (pygobject_api_functions.unblock_threads != NULL)  \
-      (* pygobject_api_functions.unblock_threads)();      \
-  } G_STMT_END
-
-#define pyg_threads_enabled (pygobject_api_functions.threads_enabled)
-
-#ifdef DISABLE_THREADING
-#define pyg_gil_state_ensure() 0
-#define pyg_gil_state_release(state) G_STMT_START {     \
-    } G_STMT_END
-
-#else
-#define pyg_gil_state_ensure() (pygobject_api_functions.threads_enabled? (PyGILState_Ensure()) : 0)
-#define pyg_gil_state_release(state) G_STMT_START {     \
-    if (pygobject_api_functions.threads_enabled)        \
-        PyGILState_Release(state);                      \
-    } G_STMT_END
-#endif
-
-#define pyg_begin_allow_threads                         \
-    G_STMT_START {                                      \
-        PyThreadState *_save = NULL;                    \
-        if (pygobject_api_functions.threads_enabled)    \
-            _save = PyEval_SaveThread();
-#define pyg_end_allow_threads                           \
-        if (pygobject_api_functions.threads_enabled)    \
-            PyEval_RestoreThread(_save);                \
-    } G_STMT_END
 
 
 #ifndef Py_CLEAR /* since Python 2.4 */
diff --git a/gi/_gobject/pygobject.h b/gi/_gobject/pygobject.h
index 3c5e384..f6b531d 100644
--- a/gi/_gobject/pygobject.h
+++ b/gi/_gobject/pygobject.h
@@ -140,6 +140,7 @@ struct _PyGObject_Functions {
                                     PyGThreadBlockFunc unblock_threads_func);
     PyGThreadBlockFunc block_threads;
     PyGThreadBlockFunc unblock_threads;
+
     PyTypeObject *paramspec_type;
     PyObject *(* paramspec_new)(GParamSpec *spec);
     GParamSpec *(*paramspec_get)(PyObject *tuple);
@@ -196,6 +197,28 @@ struct _PyGObject_Functions {
     PyTypeObject *object_type;
 };
 
+
+#ifdef DISABLE_THREADING
+#    define pyg_threads_enabled           FALSE
+#    define pyg_gil_state_ensure()        0
+#    define pyg_gil_state_release(state)
+#    define pyg_begin_allow_threads       G_STMT_START {
+#    define pyg_end_allow_threads         } G_STMT_END
+#else
+#    define pyg_threads_enabled           TRUE
+#    define pyg_gil_state_ensure          PyGILState_Ensure
+#    define pyg_gil_state_release         PyGILState_Release
+#    define pyg_begin_allow_threads       Py_BEGIN_ALLOW_THREADS
+#    define pyg_end_allow_threads         Py_END_ALLOW_THREADS
+#endif
+
+/* Deprecated, only available for API compatibility. */
+#define pyg_enable_threads()
+#define pyg_set_thread_block_funcs(a, b)
+#define pyg_block_threads()
+#define pyg_unblock_threads()
+
+
 #ifndef _INSIDE_PYGOBJECT_
 
 #if defined(NO_IMPORT) || defined(NO_IMPORT_PYGOBJECT)
@@ -233,7 +256,6 @@ struct _PyGObject_Functions *_PyGObject_API;
 #define pyg_flags_add_constants     (_PyGObject_API->flags_add_constants)
 #define pyg_constant_strip_prefix   (_PyGObject_API->constant_strip_prefix)
 #define pyg_error_check             (_PyGObject_API->error_check)
-#define pyg_set_thread_block_funcs  (_PyGObject_API->set_thread_block_funcs)
 #define PyGParamSpec_Type           (*_PyGObject_API->paramspec_type)
 #define pyg_param_spec_new          (_PyGObject_API->paramspec_new)
 #define pyg_param_spec_from_object  (_PyGObject_API->paramspec_get)
@@ -247,9 +269,6 @@ struct _PyGObject_Functions *_PyGObject_API;
 #define PyGFlags_Type               (*_PyGObject_API->flags_type)
 #define pyg_flags_add               (_PyGObject_API->flags_add)
 #define pyg_flags_from_gtype        (_PyGObject_API->flags_from_gtype)
-#define pyg_enable_threads          (_PyGObject_API->enable_threads)
-#define pyg_gil_state_ensure        (_PyGObject_API->gil_state_ensure)
-#define pyg_gil_state_release       (_PyGObject_API->gil_state_release)
 #define pyg_register_class_init     (_PyGObject_API->register_class_init)
 #define pyg_register_interface_info (_PyGObject_API->register_interface_info)
 #define pyg_add_warning_redirection   (_PyGObject_API->add_warning_redirection)
@@ -257,27 +276,6 @@ struct _PyGObject_Functions *_PyGObject_API;
 #define pyg_gerror_exception_check (_PyGObject_API->gerror_exception_check)
 #define pyg_option_group_new       (_PyGObject_API->option_group_new)
 
-#define pyg_block_threads()   G_STMT_START {   \
-    if (_PyGObject_API->block_threads != NULL) \
-      (* _PyGObject_API->block_threads)();     \
-  } G_STMT_END
-#define pyg_unblock_threads() G_STMT_START {     \
-    if (_PyGObject_API->unblock_threads != NULL) \
-      (* _PyGObject_API->unblock_threads)();     \
-  } G_STMT_END
-
-#define pyg_threads_enabled (_PyGObject_API->threads_enabled)
-
-#define pyg_begin_allow_threads                 \
-    G_STMT_START {                              \
-        PyThreadState *_save = NULL;            \
-        if (_PyGObject_API->threads_enabled)    \
-            _save = PyEval_SaveThread();
-#define pyg_end_allow_threads                   \
-        if (_PyGObject_API->threads_enabled)    \
-            PyEval_RestoreThread(_save);        \
-    } G_STMT_END
-
 
 /**
  * pygobject_init:
diff --git a/gi/gimodule.c b/gi/gimodule.c
index 108fc77..3952f91 100644
--- a/gi/gimodule.c
+++ b/gi/gimodule.c
@@ -534,6 +534,7 @@ pyg_channel_read(PyObject* self, PyObject *args, PyObject *kwargs)
     gsize total_read = 0;
     GError* error = NULL;
     GIOStatus status = G_IO_STATUS_NORMAL;
+    GIOChannel *iochannel = NULL;
 
     if (!PyArg_ParseTuple (args, "Oi:pyg_channel_read", &py_iochannel, &max_count)) {
         return NULL;
@@ -545,7 +546,9 @@ pyg_channel_read(PyObject* self, PyObject *args, PyObject *kwargs)
        
     if (max_count == 0)
         return PYGLIB_PyBytes_FromString("");
-    
+
+    iochannel = pyg_boxed_get (py_iochannel, GIOChannel);
+
     while (status == G_IO_STATUS_NORMAL
           && (max_count == -1 || total_read < max_count)) {
        gsize single_read;
@@ -572,11 +575,11 @@ pyg_channel_read(PyObject* self, PyObject *args, PyObject *kwargs)
        
         buf = PYGLIB_PyBytes_AsString(ret_obj) + total_read;
 
-        pyglib_unblock_threads();
-        status = g_io_channel_read_chars(pyg_boxed_get (py_iochannel, GIOChannel),
-                                         buf, buf_size, &single_read, &error);
-        pyglib_block_threads();
-       if (pyglib_error_check(&error))
+        pyglib_begin_allow_threads;
+        status = g_io_channel_read_chars (iochannel, buf, buf_size, &single_read, &error);
+        pyglib_end_allow_threads;
+
+        if (pyglib_error_check(&error))
            goto failure;
        
        total_read += single_read;