Move RingBuffer to separate module

Author: mgeier

rtmixer_build.py

@@ -1,55 +1,24 @@
 # This is used to create the _rtmixer extension module (see setup.py).
 
 from cffi import FFI
-import platform
+import pa_ringbuffer
 
-if platform.system() == 'Darwin':
-    ring_buffer_size_t = 'int32_t'
-else:
-    ring_buffer_size_t = 'long'
+RINGBUFFER_CDEF = pa_ringbuffer.cdef()
 
 ffibuilder = FFI()
+ffibuilder.cdef(RINGBUFFER_CDEF)
 ffibuilder.cdef("""
 
-/* From portaudio.h: */
-
-typedef double PaTime;
-typedef struct PaStreamCallbackTimeInfo PaStreamCallbackTimeInfo;
-typedef unsigned long PaStreamCallbackFlags;
-
-/* From pa_ringbuffer.h: */
-
-typedef %(ring_buffer_size_t)s ring_buffer_size_t;
-typedef struct PaUtilRingBuffer
-{
-    ring_buffer_size_t  bufferSize;
-    volatile ring_buffer_size_t writeIndex;
-    volatile ring_buffer_size_t readIndex;
-    ring_buffer_size_t bigMask;
-    ring_buffer_size_t smallMask;
-    ring_buffer_size_t elementSizeBytes;
-    char* buffer;
-} PaUtilRingBuffer;
-ring_buffer_size_t PaUtil_InitializeRingBuffer(PaUtilRingBuffer* rbuf, ring_buffer_size_t elementSizeBytes, ring_buffer_size_t elementCount, void* dataPtr);
-void PaUtil_FlushRingBuffer(PaUtilRingBuffer* rbuf);
-ring_buffer_size_t PaUtil_GetRingBufferWriteAvailable(const PaUtilRingBuffer* rbuf);
-ring_buffer_size_t PaUtil_GetRingBufferReadAvailable(const PaUtilRingBuffer* rbuf);
-ring_buffer_size_t PaUtil_WriteRingBuffer(PaUtilRingBuffer* rbuf, const void* data, ring_buffer_size_t elementCount);
-ring_buffer_size_t PaUtil_ReadRingBuffer(PaUtilRingBuffer* rbuf, void* data, ring_buffer_size_t elementCount);
-ring_buffer_size_t PaUtil_GetRingBufferWriteRegions(PaUtilRingBuffer* rbuf, ring_buffer_size_t elementCount, void** dataPtr1, ring_buffer_size_t* sizePtr1, void** dataPtr2, ring_buffer_size_t* sizePtr2);
-ring_buffer_size_t PaUtil_AdvanceRingBufferWriteIndex(PaUtilRingBuffer* rbuf, ring_buffer_size_t elementCount);
-ring_buffer_size_t PaUtil_GetRingBufferReadRegions(PaUtilRingBuffer* rbuf, ring_buffer_size_t elementCount, void** dataPtr1, ring_buffer_size_t* sizePtr1, void** dataPtr2, ring_buffer_size_t* sizePtr2);
-ring_buffer_size_t PaUtil_AdvanceRingBufferReadIndex(PaUtilRingBuffer* rbuf, ring_buffer_size_t elementCount);
-
 /* From limits.h: */
 
 #define ULONG_MAX ...
-""" % locals())
+
+""")
 ffibuilder.cdef(open('src/rtmixer.h').read())
 ffibuilder.set_source(
     '_rtmixer',
-    open('src/rtmixer.c').read(),
-    include_dirs=['src', 'portaudio/include', 'portaudio/src/common'],
+    RINGBUFFER_CDEF + open('src/rtmixer.c').read(),
+    include_dirs=['src'],
     sources=['portaudio/src/common/pa_ringbuffer.c'],
     #extra_compile_args=['-Wconversion'],
     # TODO: release mode by default, option for using debug mode

setup.py

@@ -13,9 +13,9 @@
     version=__version__,
     package_dir={'': 'src'},
     py_modules=['rtmixer'],
-    setup_requires=['CFFI>=1.4.0'],
+    setup_requires=['CFFI>=1.4.0', 'pa_ringbuffer'],
     cffi_modules=['rtmixer_build.py:ffibuilder'],
-    install_requires=['sounddevice>0.3.6'],
+    install_requires=['sounddevice>0.3.6', 'pa_ringbuffer'],
     author='Matthias Geier',
     author_email='Matthias.Geier@gmail.com',
     description='Reliable low-latency audio playback and recording',

src/rtmixer.c

@@ -1,13 +1,30 @@
-/* See ../rtmixer_build.py */
+/* See ../rtmixer_build.py, the ring buffer declarations are included there */
 
 #include <math.h>  // for llround()
 #include <stdbool.h>  // for bool, true, false
 
-#include <portaudio.h>
-#include <pa_ringbuffer.h>
-
 #include "rtmixer.h"
 
+/* From portaudio.h: */
+typedef struct PaStreamCallbackTimeInfo{
+    PaTime inputBufferAdcTime;
+    PaTime currentTime;
+    PaTime outputBufferDacTime;
+} PaStreamCallbackTimeInfo;
+typedef unsigned long PaStreamCallbackFlags;
+#define paInputUnderflow   ((PaStreamCallbackFlags) 0x00000001)
+#define paInputOverflow    ((PaStreamCallbackFlags) 0x00000002)
+#define paOutputUnderflow  ((PaStreamCallbackFlags) 0x00000004)
+#define paOutputOverflow   ((PaStreamCallbackFlags) 0x00000008)
+#define paPrimingOutput    ((PaStreamCallbackFlags) 0x00000010)
+typedef enum PaStreamCallbackResult
+{
+    paContinue=0,
+    paComplete=1,
+    paAbort=2
+} PaStreamCallbackResult;
+/* End of declarations from portaudio.h */
+
 #ifdef NDEBUG
 #define CALLBACK_ASSERT(expr) ((void)(0))
 #else

src/rtmixer.h

@@ -1,3 +1,9 @@
+/* From portaudio.h: */
+typedef double PaTime;
+typedef struct PaStreamCallbackTimeInfo PaStreamCallbackTimeInfo;
+typedef unsigned long PaStreamCallbackFlags;
+/* End of declarations from portaudio.h */
+
 typedef unsigned long frame_t;
 
 enum actiontype

src/rtmixer.py

@@ -1,8 +1,11 @@
 """Reliable low-latency audio playback and recording."""
+
 __version__ = '0.0.0'
 
 import sounddevice as _sd
+from pa_ringbuffer import init as _init_ringbuffer
 from _rtmixer import ffi as _ffi, lib as _lib
+RingBuffer = _init_ringbuffer(_ffi, _lib)
 
 
 class _Base(_sd._StreamBase):
@@ -234,194 +237,3 @@ def __init__(self, **kwargs):
         _Base.__init__(self, kind='duplex', **kwargs)
         self._state.input_channels = self.channels[0]
         self._state.output_channels = self.channels[1]
-
-
-class RingBuffer(object):
-    """Wrapper for PortAudio's ring buffer.
-
-    See __init__().
-
-    """
-
-    def __init__(self, elementsize, size):
-        """Create an instance of PortAudio's ring buffer.
-
-        Parameters
-        ----------
-        elementsize : int
-            The size of a single data element in bytes.
-        size : int
-            The number of elements in the buffer (must be a power of 2).
-
-        """
-        self._ptr = _ffi.new('PaUtilRingBuffer*')
-        self._data = _ffi.new('unsigned char[]', size * elementsize)
-        res = _lib.PaUtil_InitializeRingBuffer(
-            self._ptr, elementsize, size, self._data)
-        if res != 0:
-            assert res == -1
-            raise ValueError('size must be a power of 2')
-        assert self._ptr.bufferSize == size
-        assert self._ptr.elementSizeBytes == elementsize
-
-    def flush(self):
-        """Reset buffer to empty.
-
-        Should only be called when buffer is NOT being read or written.
-
-        """
-        _lib.PaUtil_FlushRingBuffer(self._ptr)
-
-    @property
-    def write_available(self):
-        """Number of elements available in the ring buffer for writing."""
-        return _lib.PaUtil_GetRingBufferWriteAvailable(self._ptr)
-
-    @property
-    def read_available(self):
-        """Number of elements available in the ring buffer for reading."""
-        return _lib.PaUtil_GetRingBufferReadAvailable(self._ptr)
-
-    def write(self, data, size=-1):
-        """Write data to the ring buffer.
-
-        Parameters
-        ----------
-        data : CData pointer or buffer or bytes
-            Data to write to the buffer.
-        size : int, optional
-            The number of elements to be written.
-
-        Returns
-        -------
-        int
-            The number of elements written.
-
-        """
-        try:
-            data = _ffi.from_buffer(data)
-        except TypeError:
-            pass  # input is not a buffer
-        if size < 0:
-            size, rest = divmod(_ffi.sizeof(data), self._ptr.elementSizeBytes)
-            if rest:
-                raise ValueError('data size must be multiple of elementsize')
-        return _lib.PaUtil_WriteRingBuffer(self._ptr, data, size)
-
-    def read(self, data, size=-1):
-        """Read data from the ring buffer.
-
-        Parameters
-        ----------
-        data : CData pointer or buffer
-            The memory where the data should be stored.
-        size : int, optional
-            The number of elements to be read.
-
-        Returns
-        -------
-        int
-            The number of elements read.
-
-        """
-        try:
-            data = _ffi.from_buffer(data)
-        except TypeError:
-            pass  # input is not a buffer
-        if size < 0:
-            size, rest = divmod(_ffi.sizeof(data), self._ptr.elementSizeBytes)
-            if rest:
-                raise ValueError('data size must be multiple of elementsize')
-        return _lib.PaUtil_ReadRingBuffer(self._ptr, data, size)
-
-    def get_write_buffers(self, size):
-        """Get buffer(s) to which we can write data.
-
-        Parameters
-        ----------
-        size : int
-            The number of elements desired.
-
-        Returns
-        -------
-        int
-            The room available to be written or the given *size*,
-            whichever is smaller.
-        buffer
-            The first buffer.
-        buffer
-            The second buffer.
-
-        """
-        ptr1 = _ffi.new('void**')
-        ptr2 = _ffi.new('void**')
-        size1 = _ffi.new('ring_buffer_size_t*')
-        size2 = _ffi.new('ring_buffer_size_t*')
-        return (_lib.PaUtil_GetRingBufferWriteRegions(
-                    self._ptr, size, ptr1, size1, ptr2, size2),
-                _ffi.buffer(ptr1[0], size1[0] * self.elementsize),
-                _ffi.buffer(ptr2[0], size2[0] * self.elementsize))
-
-    def advance_write_index(self, size):
-        """Advance the write index to the next location to be written.
-
-        Parameters
-        ----------
-        size : int
-            The number of elements to advance.
-
-        Returns
-        -------
-        int
-            The new position.
-
-        """
-        return _lib.PaUtil_AdvanceRingBufferWriteIndex(self._ptr, size)
-
-    def get_read_buffers(self, size):
-        """Get buffer(s) from which we can read data.
-
-        Parameters
-        ----------
-        size : int
-            The number of elements desired.
-
-        Returns
-        -------
-        int
-            The number of elements available for reading.
-        buffer
-            The first buffer.
-        buffer
-            The second buffer.
-
-        """
-        ptr1 = _ffi.new('void**')
-        ptr2 = _ffi.new('void**')
-        size1 = _ffi.new('ring_buffer_size_t*')
-        size2 = _ffi.new('ring_buffer_size_t*')
-        return (_lib.PaUtil_GetRingBufferReadRegions(
-                    self._ptr, size, ptr1, size1, ptr2, size2),
-                _ffi.buffer(ptr1[0], size1[0] * self.elementsize),
-                _ffi.buffer(ptr2[0], size2[0] * self.elementsize))
-
-    def advance_read_index(self, size):
-        """Advance the read index to the next location to be read.
-
-        Parameters
-        ----------
-        size : int
-            The number of elements to advance.
-
-        Returns
-        -------
-        int
-            The new position.
-
-        """
-        return _lib.PaUtil_AdvanceRingBufferReadIndex(self._ptr, size)
-
-    @property
-    def elementsize(self):
-        """Element size in bytes."""
-        return self._ptr.elementSizeBytes