Vendor discord.py (#2387)

Signed-off-by: Toby Harradine <tobyharradine@gmail.com>

discord/opus.py

@@ -0,0 +1,286 @@
+# -*- coding: utf-8 -*-
+
+"""
+The MIT License (MIT)
+
+Copyright (c) 2015-2017 Rapptz
+
+Permission is hereby granted, free of charge, to any person obtaining a
+copy of this software and associated documentation files (the "Software"),
+to deal in the Software without restriction, including without limitation
+the rights to use, copy, modify, merge, publish, distribute, sublicense,
+and/or sell copies of the Software, and to permit persons to whom the
+Software is furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+DEALINGS IN THE SOFTWARE.
+"""
+
+import array
+import ctypes
+import ctypes.util
+import logging
+import os.path
+import sys
+
+from .errors import DiscordException
+
+log = logging.getLogger(__name__)
+c_int_ptr = ctypes.POINTER(ctypes.c_int)
+c_int16_ptr = ctypes.POINTER(ctypes.c_int16)
+c_float_ptr = ctypes.POINTER(ctypes.c_float)
+
+
+class EncoderStruct(ctypes.Structure):
+    pass
+
+
+EncoderStructPtr = ctypes.POINTER(EncoderStruct)
+
+
+def _err_lt(result, func, args):
+    if result < 0:
+        log.info("error has happened in %s", func.__name__)
+        raise OpusError(result)
+    return result
+
+
+def _err_ne(result, func, args):
+    ret = args[-1]._obj
+    if ret.value != 0:
+        log.info("error has happened in %s", func.__name__)
+        raise OpusError(ret.value)
+    return result
+
+
+# A list of exported functions.
+# The first argument is obviously the name.
+# The second one are the types of arguments it takes.
+# The third is the result type.
+# The fourth is the error handler.
+exported_functions = [
+    ("opus_strerror", [ctypes.c_int], ctypes.c_char_p, None),
+    ("opus_encoder_get_size", [ctypes.c_int], ctypes.c_int, None),
+    (
+        "opus_encoder_create",
+        [ctypes.c_int, ctypes.c_int, ctypes.c_int, c_int_ptr],
+        EncoderStructPtr,
+        _err_ne,
+    ),
+    (
+        "opus_encode",
+        [EncoderStructPtr, c_int16_ptr, ctypes.c_int, ctypes.c_char_p, ctypes.c_int32],
+        ctypes.c_int32,
+        _err_lt,
+    ),
+    ("opus_encoder_ctl", None, ctypes.c_int32, _err_lt),
+    ("opus_encoder_destroy", [EncoderStructPtr], None, None),
+]
+
+
+def libopus_loader(name):
+    # create the library...
+    lib = ctypes.cdll.LoadLibrary(name)
+
+    # register the functions...
+    for item in exported_functions:
+        func = getattr(lib, item[0])
+
+        try:
+            if item[1]:
+                func.argtypes = item[1]
+
+            func.restype = item[2]
+        except KeyError:
+            pass
+
+        try:
+            if item[3]:
+                func.errcheck = item[3]
+        except KeyError:
+            log.exception("Error assigning check function to %s", func)
+
+    return lib
+
+
+try:
+    if sys.platform == "win32":
+        _basedir = os.path.dirname(os.path.abspath(__file__))
+        _bitness = "x64" if sys.maxsize > 2 ** 32 else "x86"
+        _filename = os.path.join(_basedir, "bin", "libopus-0.{}.dll".format(_bitness))
+        _lib = libopus_loader(_filename)
+    else:
+        _lib = libopus_loader(ctypes.util.find_library("opus"))
+except Exception:
+    _lib = None
+
+
+def load_opus(name):
+    """Loads the libopus shared library for use with voice.
+
+    If this function is not called then the library uses the function
+    `ctypes.util.find_library`__ and then loads that one
+    if available.
+
+    .. _find library: https://docs.python.org/3.5/library/ctypes.html#finding-shared-libraries
+    __ `find library`_
+
+    Not loading a library leads to voice not working.
+
+    This function propagates the exceptions thrown.
+
+    Warning
+    --------
+    The bitness of the library must match the bitness of your python
+    interpreter. If the library is 64-bit then your python interpreter
+    must be 64-bit as well. Usually if there's a mismatch in bitness then
+    the load will throw an exception.
+
+    Note
+    ----
+    On Windows, the .dll extension is not necessary. However, on Linux
+    the full extension is required to load the library, e.g. ``libopus.so.1``.
+    On Linux however, `find library`_ will usually find the library automatically
+    without you having to call this.
+
+    Parameters
+    ----------
+    name: str
+        The filename of the shared library.
+    """
+    global _lib
+    _lib = libopus_loader(name)
+
+
+def is_loaded():
+    """Function to check if opus lib is successfully loaded either
+    via the ``ctypes.util.find_library`` call of :func:`load_opus`.
+
+    This must return ``True`` for voice to work.
+
+    Returns
+    -------
+    bool
+        Indicates if the opus library has been loaded.
+    """
+    global _lib
+    return _lib is not None
+
+
+class OpusError(DiscordException):
+    """An exception that is thrown for libopus related errors.
+
+    Attributes
+    ----------
+    code : :class:`int`
+        The error code returned.
+    """
+
+    def __init__(self, code):
+        self.code = code
+        msg = _lib.opus_strerror(self.code).decode("utf-8")
+        log.info('"%s" has happened', msg)
+        super().__init__(msg)
+
+
+class OpusNotLoaded(DiscordException):
+    """An exception that is thrown for when libopus is not loaded."""
+
+    pass
+
+
+# Some constants...
+OK = 0
+APPLICATION_AUDIO = 2049
+APPLICATION_VOIP = 2048
+APPLICATION_LOWDELAY = 2051
+CTL_SET_BITRATE = 4002
+CTL_SET_BANDWIDTH = 4008
+CTL_SET_FEC = 4012
+CTL_SET_PLP = 4014
+CTL_SET_SIGNAL = 4024
+
+band_ctl = {"narrow": 1101, "medium": 1102, "wide": 1103, "superwide": 1104, "full": 1105}
+
+signal_ctl = {"auto": -1000, "voice": 3001, "music": 3002}
+
+
+class Encoder:
+    SAMPLING_RATE = 48000
+    CHANNELS = 2
+    FRAME_LENGTH = 20
+    SAMPLE_SIZE = 4  # (bit_rate / 8) * CHANNELS (bit_rate == 16)
+    SAMPLES_PER_FRAME = int(SAMPLING_RATE / 1000 * FRAME_LENGTH)
+
+    FRAME_SIZE = SAMPLES_PER_FRAME * SAMPLE_SIZE
+
+    def __init__(self, application=APPLICATION_AUDIO):
+        self.application = application
+
+        if not is_loaded():
+            raise OpusNotLoaded()
+
+        self._state = self._create_state()
+        self.set_bitrate(128)
+        self.set_fec(True)
+        self.set_expected_packet_loss_percent(0.15)
+        self.set_bandwidth("full")
+        self.set_signal_type("auto")
+
+    def __del__(self):
+        if hasattr(self, "_state"):
+            _lib.opus_encoder_destroy(self._state)
+            self._state = None
+
+    def _create_state(self):
+        ret = ctypes.c_int()
+        return _lib.opus_encoder_create(
+            self.SAMPLING_RATE, self.CHANNELS, self.application, ctypes.byref(ret)
+        )
+
+    def set_bitrate(self, kbps):
+        kbps = min(128, max(16, int(kbps)))
+
+        _lib.opus_encoder_ctl(self._state, CTL_SET_BITRATE, kbps * 1024)
+        return kbps
+
+    def set_bandwidth(self, req):
+        if req not in band_ctl:
+            raise KeyError(
+                "%r is not a valid bandwidth setting. Try one of: %s" % (req, ",".join(band_ctl))
+            )
+
+        k = band_ctl[req]
+        _lib.opus_encoder_ctl(self._state, CTL_SET_BANDWIDTH, k)
+
+    def set_signal_type(self, req):
+        if req not in signal_ctl:
+            raise KeyError(
+                "%r is not a valid signal setting. Try one of: %s" % (req, ",".join(signal_ctl))
+            )
+
+        k = signal_ctl[req]
+        _lib.opus_encoder_ctl(self._state, CTL_SET_SIGNAL, k)
+
+    def set_fec(self, enabled=True):
+        _lib.opus_encoder_ctl(self._state, CTL_SET_FEC, 1 if enabled else 0)
+
+    def set_expected_packet_loss_percent(self, percentage):
+        _lib.opus_encoder_ctl(self._state, CTL_SET_PLP, min(100, max(0, int(percentage * 100))))
+
+    def encode(self, pcm, frame_size):
+        max_data_bytes = len(pcm)
+        pcm = ctypes.cast(pcm, c_int16_ptr)
+        data = (ctypes.c_char * max_data_bytes)()
+
+        ret = _lib.opus_encode(self._state, pcm, frame_size, data, max_data_bytes)
+
+        return array.array("b", data[:ret]).tobytes()