Rework exception raising to handle GIL acquisition more efficiently

cysounddevice/conversion.pxd

@@ -4,15 +4,15 @@ from cysounddevice.pawrapper cimport *
 from cysounddevice.types cimport *
 from cysounddevice.buffer cimport BufferItem
 
-cdef void pack_buffer_item(BufferItem* item, float[:,:] src) nogil
+cdef int pack_buffer_item(BufferItem* item, float[:,:] src) nogil except -1
 cdef void pack_float32(BufferItem* item, float[:,:] src) nogil
 cdef void pack_sint32(BufferItem* item, float[:,:] src) nogil
 cdef void pack_sint24(BufferItem* item, float[:,:] src) nogil
 cdef void pack_sint16(BufferItem* item, float[:,:] src) nogil
 cdef void pack_sint8(BufferItem* item, float[:,:] src) nogil
 cdef void pack_uint8(BufferItem* item, float[:,:] src) nogil
 
-cdef void unpack_buffer_item(BufferItem* item, float[:,:] dest) nogil
+cdef int unpack_buffer_item(BufferItem* item, float[:,:] dest) nogil except -1
 cdef void unpack_float32(BufferItem* item, float[:,:] dest) nogil
 cdef void unpack_sint32(BufferItem* item, float[:,:] dest) nogil
 cdef void unpack_sint24(BufferItem* item, float[:,:] dest) nogil

cysounddevice/conversion.pyx

@@ -3,13 +3,15 @@
 # TODO: Endian-ness should be checked at compilation time
 DEF LITTLE_ENDIAN = True
 
+from cysounddevice.utils cimport raise_withgil, PyExc_ValueError
+
 # -----------------------------------------------------------------------------
 # Convert from 2-dimensional float32 array/memoryview into flattened values
 # scaled for the SampleBuffer's sample_format, then pack them
 # into the BufferItem's char buffer.
 # -----------------------------------------------------------------------------
 
-cdef void pack_buffer_item(BufferItem* item, float[:,:] src) nogil:
+cdef int pack_buffer_item(BufferItem* item, float[:,:] src) nogil except -1:
     cdef SampleFormat* fmt = item.parent_buffer.sample_format
     if fmt.pa_ident == paFloat32:
         pack_float32(item, src)
@@ -24,8 +26,8 @@ cdef void pack_buffer_item(BufferItem* item, float[:,:] src) nogil:
     elif fmt.pa_ident == paUInt8:
         pack_uint8(item, src)
     else:
-        with gil:
-            raise Exception('Unsupported format')
+        raise_withgil(PyExc_ValueError, 'Unsupported format')
+    return 0
 
 cdef void pack_float32(BufferItem* item, float[:,:] src) nogil:
     cdef Py_ssize_t i, chan_ix, chan_num
@@ -149,7 +151,7 @@ cdef void pack_uint8(BufferItem* item, float[:,:] src) nogil:
 # placing the results into a 2-dimensional array/memoryview.
 # -----------------------------------------------------------------------------
 
-cdef void unpack_buffer_item(BufferItem* item, float[:,:] dest) nogil:
+cdef int unpack_buffer_item(BufferItem* item, float[:,:] dest) nogil except -1:
     cdef SampleFormat* fmt = item.parent_buffer.sample_format
     if fmt.pa_ident == paFloat32:
         unpack_float32(item, dest)
@@ -164,8 +166,8 @@ cdef void unpack_buffer_item(BufferItem* item, float[:,:] dest) nogil:
     elif fmt.pa_ident == paUInt8:
         unpack_uint8(item, dest)
     else:
-        with gil:
-            raise Exception('Unsupported format')
+        raise_withgil(PyExc_ValueError, 'Unsupported format')
+    return 0
 
 cdef void unpack_float32(BufferItem* item, float[:,:] dest) nogil:
     cdef Py_ssize_t i, chan_ix, chan_num

cysounddevice/devices.pyx

@@ -7,7 +7,7 @@ cimport cython
 import atexit
 
 from cysounddevice.pawrapper cimport *
-from cysounddevice.utils cimport handle_error
+from cysounddevice.utils cimport handle_pa_error
 
 cdef class DeviceInfo:
     """Container for information about particular device
@@ -186,8 +186,8 @@ cdef class PortAudio:
         if self._initialized:
             return
         self._initialized = True
-        handle_error(PaJack_SetClientName(self.jack_client_name_ptr))
-        handle_error(Pa_Initialize())
+        handle_pa_error(PaJack_SetClientName(self.jack_client_name_ptr))
+        handle_pa_error(Pa_Initialize())
         self._get_info()
     cpdef close(self):
         """Close all streams and terminates the PortAudio library
@@ -209,7 +209,7 @@ cdef class PortAudio:
         self.host_apis_by_name.clear()
         self.devices_by_name.clear()
         self.devices_by_paindex.clear()
-        handle_error(Pa_Terminate())
+        handle_pa_error(Pa_Terminate())
     def __enter__(self):
         self.open()
         return self

cysounddevice/stream_callback.pyx

@@ -133,8 +133,7 @@ cdef class StreamCallback:
         if self.user_data:
             user_data = self.user_data
             if user_data.error_status != CallbackError_none:
-                with gil:
-                    raise_stream_callback_error(user_data)
+                raise_stream_callback_error(user_data)
         return 0
 
 @cython.boundscheck(False)
@@ -198,7 +197,7 @@ cdef int _stream_callback(const void* in_bfr,
         samp_bfr.current_block += 1
     return paContinue
 
-cdef raise_stream_callback_error(CallbackUserData* user_data):
+cdef int raise_stream_callback_error(CallbackUserData* user_data) except -1 with gil:
     cdef PaStreamCallbackFlags cb_flags = user_data.last_callback_flags
     cdef object msg = None
     if user_data.error_status == CallbackError_flags:
@@ -212,15 +211,16 @@ cdef raise_stream_callback_error(CallbackUserData* user_data):
         if cb_flags & 8:
             msgs.append('Output Overflow')
         if not len(msgs):
-            return
+            return 0
         msg = ', '.join(msgs)
     elif user_data.error_status == CallbackError_input_aborted:
         msg = 'Input Aborted'
     elif user_data.error_status == CallbackError_output_aborted:
         msg = 'Output Aborted'
     else:
-        return
+        return 0
     warnings.warn(StreamCallbackError(msg))
+    return 0
 
 cdef void callback_user_data_destroy(CallbackUserData* user_data) except *:
     if user_data.in_buffer != NULL:

cysounddevice/streams.pyx

@@ -3,7 +3,7 @@
 cimport cython
 
 from cysounddevice.pawrapper cimport *
-from cysounddevice.utils cimport handle_error
+from cysounddevice.utils cimport handle_pa_error
 from cysounddevice.devices cimport DeviceInfo
 from cysounddevice.types cimport *
 from cysounddevice.stream_callback cimport StreamCallback, CallbackUserData
@@ -115,7 +115,7 @@ cdef class Stream:
             self.sample_rate,
         )
         if err != 0:
-            handle_error(err)
+            handle_pa_error(err)
         return err
     cpdef check_active(self):
         cdef PaError err
@@ -131,7 +131,7 @@ cdef class Stream:
                 active = False
                 self._pa_stream_ptr = NULL
             else:
-                handle_error(err)
+                handle_pa_error(err)
         return active
     cpdef open(self):
         """Open the stream and begin audio processing
@@ -151,7 +151,7 @@ cdef class Stream:
         ))
         self.callback_handler._build_user_data()
         cdef CallbackUserData* user_data = self.callback_handler.user_data
-        handle_error(Pa_OpenStream(
+        handle_pa_error(Pa_OpenStream(
             &ptr,
             pa_input_params,
             pa_output_params,
@@ -174,7 +174,7 @@ cdef class Stream:
         self._pa_stream_ptr = ptr
         cdef PaError err = Pa_StartStream(ptr)
         if err != paStreamIsNotStopped:
-            handle_error(err)
+            handle_pa_error(err)
         self.starting = False
         # print('waiting...')
         # Pa_Sleep(5000)
@@ -194,7 +194,7 @@ cdef class Stream:
             Pa_AbortStream(ptr)
 
         self._pa_stream_ptr = NULL
-        # handle_error(Pa_StopStream(self._pa_stream_ptr))
+        # handle_pa_error(Pa_StopStream(self._pa_stream_ptr))
         # print('stopped')
         self.callback_handler._free_user_data()
         print('closed')

cysounddevice/utils.pxd

@@ -1,6 +1,14 @@
 # cython: language_level=3
 
 # from . cimport pawrapper as pa
+
+cdef extern from 'Python.h':
+    ctypedef struct PyObject
+    PyObject *PyExc_Exception
+    PyObject *PyExc_ValueError
+
 from cysounddevice.pawrapper cimport *
 
-cpdef handle_error(PaError err)
+cdef int raise_withgil(PyObject *error, char *msg) except -1 with gil
+
+cdef int handle_pa_error(PaError err) nogil except -1

cysounddevice/utils.pyx

@@ -1,6 +1,8 @@
 
 from cysounddevice cimport pawrapper
 
+cdef int raise_withgil(PyObject *error, char *msg) except -1 with gil:
+    raise (<object>error)(msg.decode('ascii'))
 
 class PortAudioError(Exception):
     def __init__(self, error_msg, err_code, host_info=None):
@@ -10,9 +12,12 @@ class PortAudioError(Exception):
     def __str__(self):
         return repr(self.error_msg)
 
-cpdef handle_error(PaError err):
-    if err == paNoError:
-        return
+cdef int handle_pa_error(PaError err) nogil except -1:
+    if err != paNoError:
+        raise_pa_error(err)
+    return 0
+
+cdef int raise_pa_error(PaError err) except -1 with gil:
     cdef bytes msg_bytes = Pa_GetErrorText(err)
     cdef str msg_str = msg_bytes.decode('UTF-8')
     raise PortAudioError(msg_str, err)