aifc, sunau: make rate an int; os: restruct; ospath: obsolete; rfc822:

date and addr parsing; string: force result of atof to float and
support atoi, atol, atof in strop; tzparcs: don't call test().

1 files changed, 559 insertions, 0 deletions

diff --git a/Lib/wave.py b/Lib/wave.py
new file mode 100644
index 0000000000..5d1a1c1629
--- /dev/null
+++ b/Lib/wave.py
@@ -0,0 +1,559 @@
+# Stuff to parse WAVE files.
+#
+# Usage.
+#
+# Reading WAVE files:
+#	f = wave.open(file, 'r')
+# where file is either the name of a file or an open file pointer.
+# The open file pointer must have methods read(), seek(), and close().
+# When the setpos() and rewind() methods are not used, the seek()
+# method is not  necessary.
+#
+# This returns an instance of a class with the following public methods:
+#	getnchannels()	-- returns number of audio channels (1 for
+#			   mono, 2 for stereo)
+#	getsampwidth()	-- returns sample width in bytes
+#	getframerate()	-- returns sampling frequency
+#	getnframes()	-- returns number of audio frames
+#	getcomptype()	-- returns compression type ('NONE' for AIFF files)
+#	getcompname()	-- returns human-readable version of
+#			   compression type ('not compressed' for AIFF files)
+#	getparams()	-- returns a tuple consisting of all of the
+#			   above in the above order
+#	getmarkers()	-- returns None (for compatibility with the
+#			   aifc module)
+#	getmark(id)	-- raises an error since the mark does not
+#			   exist (for compatibility with the aifc module)
+#	readframes(n)	-- returns at most n frames of audio
+#	rewind()	-- rewind to the beginning of the audio stream
+#	setpos(pos)	-- seek to the specified position
+#	tell()		-- return the current position
+#	close()		-- close the instance (make it unusable)
+# The position returned by tell() and the position given to setpos()
+# are compatible and have nothing to do with the actual postion in the
+# file.
+# The close() method is called automatically when the class instance
+# is destroyed.
+#
+# Writing WAVE files:
+#	f = wave.open(file, 'w')
+# where file is either the name of a file or an open file pointer.
+# The open file pointer must have methods write(), tell(), seek(), and
+# close().
+#
+# This returns an instance of a class with the following public methods:
+#	setnchannels(n)	-- set the number of channels
+#	setsampwidth(n)	-- set the sample width
+#	setframerate(n)	-- set the frame rate
+#	setnframes(n)	-- set the number of frames
+#	setcomptype(type, name)
+#			-- set the compression type and the
+#			   human-readable compression type
+#	setparams(nchannels, sampwidth, framerate, nframes, comptype, compname)
+#			-- set all parameters at once
+#	tell()		-- return current position in output file
+#	writeframesraw(data)
+#			-- write audio frames without pathing up the
+#			   file header
+#	writeframes(data)
+#			-- write audio frames and patch up the file header
+#	close()		-- patch up the file header and close the
+#			   output file
+# You should set the parameters before the first writeframesraw or
+# writeframes.  The total number of frames does not need to be set,
+# but when it is set to the correct value, the header does not have to
+# be patched up.
+# It is best to first set all parameters, perhaps possibly the
+# compression type, and then write audio frames using writeframesraw.
+# When all frames have been written, either call writeframes('') or
+# close() to patch up the sizes in the header.
+# The close() method is called automatically when the class instance
+# is destroyed.
+
+import __builtin__
+
+Error = 'wave.Error'
+
+WAVE_FORMAT_PCM = 0x0001
+
+_array_fmts = None, 'b', 'h', None, 'l'
+
+def _read_long(file):
+	x = 0L
+	for i in range(4):
+		byte = file.read(1)
+		if byte == '':
+			raise EOFError
+		x = x + (ord(byte) << (8 * i))
+	if x >= 0x80000000L:
+		x = x - 0x100000000L
+	return int(x)
+
+def _read_ulong(file):
+	x = 0L
+	for i in range(4):
+		byte = file.read(1)
+		if byte == '':
+			raise EOFError
+		x = x + (ord(byte) << (8 * i))
+	return x
+
+def _read_short(file):
+	x = 0
+	for i in range(2):
+		byte = file.read(1)
+		if byte == '':
+			raise EOFError
+		x = x + (ord(byte) << (8 * i))
+	if x >= 0x8000:
+		x = x - 0x10000
+	return x
+
+def _write_short(f, x):
+	d, m = divmod(x, 256)
+	f.write(chr(m))
+	f.write(chr(d))
+
+def _write_long(f, x):
+	if x < 0:
+		x = x + 0x100000000L
+	for i in range(4):
+		d, m = divmod(x, 256)
+		f.write(chr(int(m)))
+		x = d
+
+class Chunk:
+	def __init__(self, file):
+		self.file = file
+		self.chunkname = self.file.read(4)
+		if len(self.chunkname) < 4:
+			raise EOFError
+		self.chunksize = _read_long(self.file)
+		self.size_read = 0
+		self.offset = self.file.tell()
+
+	def rewind(self):
+		self.file.seek(self.offset, 0)
+		self.size_read = 0
+
+	def setpos(self, pos):
+		if pos < 0 or pos > self.chunksize:
+			raise RuntimeError
+		self.file.seek(self.offset + pos, 0)
+		self.size_read = pos
+		
+	def read(self, length):
+		if self.size_read >= self.chunksize:
+			return ''
+		if length > self.chunksize - self.size_read:
+ 			length = self.chunksize - self.size_read
+		data = self.file.read(length)
+		self.size_read = self.size_read + len(data)
+		return data
+
+	def skip(self):
+		try:
+			self.file.seek(self.chunksize - self.size_read, 1)
+		except RuntimeError:
+			while self.size_read < self.chunksize:
+				dummy = self.read(8192)
+				if not dummy:
+					raise EOFError
+
+class Wave_read:
+	# Variables used in this class:
+	#
+	# These variables are available to the user though appropriate
+	# methods of this class:
+	# _file -- the open file with methods read(), close(), and seek()
+	#		set through the __init__() method
+	# _nchannels -- the number of audio channels
+	#		available through the getnchannels() method
+	# _nframes -- the number of audio frames
+	#		available through the getnframes() method
+	# _sampwidth -- the number of bytes per audio sample
+	#		available through the getsampwidth() method
+	# _framerate -- the sampling frequency
+	#		available through the getframerate() method
+	# _comptype -- the AIFF-C compression type ('NONE' if AIFF)
+	#		available through the getcomptype() method
+	# _compname -- the human-readable AIFF-C compression type
+	#		available through the getcomptype() method
+	# _soundpos -- the position in the audio stream
+	#		available through the tell() method, set through the
+	#		setpos() method
+	#
+	# These variables are used internally only:
+	# _fmt_chunk_read -- 1 iff the FMT chunk has been read
+	# _data_seek_needed -- 1 iff positioned correctly in audio
+	#		file for readframes()
+	# _data_chunk -- instantiation of a chunk class for the DATA chunk
+	# _framesize -- size of one frame in the file
+
+	access _file, _nchannels, _nframes, _sampwidth, _framerate, \
+		  _comptype, _compname, _soundpos, \
+		  _fmt_chunk_read, _data_seek_needed, \
+		  _data_chunk, _framesize: private
+
+	def initfp(self, file):
+		self._file = file
+		self._convert = None
+		self._soundpos = 0
+		form = self._file.read(4)
+		if form != 'RIFF':
+			raise Error, 'file does not start with RIFF id'
+		formlength = _read_long(self._file)
+		if formlength <= 0:
+			raise Error, 'invalid FORM chunk data size'
+		formdata = self._file.read(4)
+		formlength = formlength - 4
+		if formdata != 'WAVE':
+			raise Error, 'not a WAVE file'
+		self._fmt_chunk_read = 0
+		while formlength > 0:
+			self._data_seek_needed = 1
+			chunk = Chunk(self._file)
+			if chunk.chunkname == 'fmt ':
+				self._read_fmt_chunk(chunk)
+				self._fmt_chunk_read = 1
+			elif chunk.chunkname == 'data':
+				if not self._fmt_chunk_read:
+					raise Error, 'data chunk before fmt chunk'
+				self._data_chunk = chunk
+				self._nframes = chunk.chunksize / self._framesize
+				self._data_seek_needed = 0
+			formlength = formlength - 8 - chunk.chunksize
+			if formlength > 0:
+				chunk.skip()
+		if not self._fmt_chunk_read or not self._data_chunk:
+			raise Error, 'fmt chunk and/or data chunk missing'
+
+	def __init__(self, f):
+		if type(f) == type(''):
+			f = __builtin__.open(f, 'r')
+		# else, assume it is an open file object already
+		self.initfp(f)
+
+	def __del__(self):
+		if self._file:
+			self.close()
+
+	#
+	# User visible methods.
+	#
+	def getfp(self):
+		return self._file
+
+	def rewind(self):
+		self._data_seek_needed = 1
+		self._soundpos = 0
+
+	def close(self):
+		self._file = None
+
+	def tell(self):
+		return self._soundpos
+
+	def getnchannels(self):
+		return self._nchannels
+
+	def getnframes(self):
+		return self._nframes
+
+	def getsampwidth(self):
+		return self._sampwidth
+
+	def getframerate(self):
+		return self._framerate
+
+	def getcomptype(self):
+		return self._comptype
+
+	def getcompname(self):
+		return self._compname
+
+	def getparams(self):
+		return self.getnchannels(), self.getsampwidth(), \
+			  self.getframerate(), self.getnframes(), \
+			  self.getcomptype(), self.getcompname()
+
+	def getmarkers(self):
+		return None
+
+	def getmark(self, id):
+		raise Error, 'no marks'
+
+	def setpos(self, pos):
+		if pos < 0 or pos > self._nframes:
+			raise Error, 'position not in range'
+		self._soundpos = pos
+		self._data_seek_needed = 1
+
+	def readframes(self, nframes):
+		if self._data_seek_needed:
+			self._data_chunk.rewind()
+			pos = self._soundpos * self._framesize
+			if pos:
+				self._data_chunk.setpos(pos)
+			self._data_seek_needed = 0
+		if nframes == 0:
+			return ''
+		if self._sampwidth > 1:
+			# unfortunately the fromfile() method does not take
+			# something that only looks like a file object, so
+			# we have to reach into the innards of the chunk object
+			import array
+			data = array.array(_array_fmts[self._sampwidth])
+			nitems = nframes * self._nchannels
+			if nitems * self._sampwidth > self._data_chunk.chunksize - self._data_chunk.size_read:
+				nitems = (self._data_chunk.chunksize - self._data_chunk.size_read) / self._sampwidth
+			data.fromfile(self._data_chunk.file, nitems)
+			self._data_chunk.size_read = self._data_chunk.size_read + nitems * self._sampwidth
+			data.byteswap()
+			data = data.tostring()
+		else:
+			data = self._data_chunk.read(nframes * self._framesize)
+		if self._convert and data:
+			data = self._convert(data)
+		self._soundpos = self._soundpos + len(data) / (self._nchannels * self._sampwidth)
+		return data
+
+	#
+	# Internal methods.
+	#
+	access *: private
+
+	def _read_fmt_chunk(self, chunk):
+		wFormatTag = _read_short(chunk)
+		self._nchannels = _read_short(chunk)
+		self._framerate = _read_long(chunk)
+		dwAvgBytesPerSec = _read_long(chunk)
+		wBlockAlign = _read_short(chunk)
+		if wFormatTag == WAVE_FORMAT_PCM:
+			self._sampwidth = (_read_short(chunk) + 7) / 8
+		else:
+			raise Error, 'unknown format'
+		self._framesize = self._nchannels * self._sampwidth
+		self._comptype = 'NONE'
+		self._compname = 'not compressed'
+
+class Wave_write:
+	# Variables used in this class:
+	#
+	# These variables are user settable through appropriate methods
+	# of this class:
+	# _file -- the open file with methods write(), close(), tell(), seek()
+	#		set through the __init__() method
+	# _comptype -- the AIFF-C compression type ('NONE' in AIFF)
+	#		set through the setcomptype() or setparams() method
+	# _compname -- the human-readable AIFF-C compression type
+	#		set through the setcomptype() or setparams() method
+	# _nchannels -- the number of audio channels
+	#		set through the setnchannels() or setparams() method
+	# _sampwidth -- the number of bytes per audio sample
+	#		set through the setsampwidth() or setparams() method
+	# _framerate -- the sampling frequency
+	#		set through the setframerate() or setparams() method
+	# _nframes -- the number of audio frames written to the header
+	#		set through the setnframes() or setparams() method
+	#
+	# These variables are used internally only:
+	# _datalength -- the size of the audio samples written to the header
+	# _nframeswritten -- the number of frames actually written
+	# _datawritten -- the size of the audio samples actually written
+
+	access _file, _comptype, _compname, _nchannels, _sampwidth, \
+		  _framerate, _nframes, _nframeswritten, \
+		  _datalength, _datawritten: private
+
+	def __init__(self, f):
+		if type(f) == type(''):
+			f = __builtin__.open(f, 'w')
+		self.initfp(f)
+
+	def initfp(self, file):
+		self._file = file
+		self._convert = None
+		self._nchannels = 0
+		self._sampwidth = 0
+		self._framerate = 0
+		self._nframes = 0
+		self._nframeswritten = 0
+		self._datawritten = 0
+		self._datalength = 0
+
+	def __del__(self):
+		if self._file:
+			self.close()
+
+	#
+	# User visible methods.
+	#
+	def setnchannels(self, nchannels):
+		if self._datawritten:
+			raise Error, 'cannot change parameters after starting to write'
+		if nchannels < 1:
+			raise Error, 'bad # of channels'
+		self._nchannels = nchannels
+
+	def getnchannels(self):
+		if not self._nchannels:
+			raise Error, 'number of channels not set'
+		return self._nchannels
+
+	def setsampwidth(self, sampwidth):
+		if self._datawritten:
+			raise Error, 'cannot change parameters after starting to write'
+		if sampwidth < 1 or sampwidth > 4:
+			raise Error, 'bad sample width'
+		self._sampwidth = sampwidth
+
+	def getsampwidth(self):
+		if not self._sampwidth:
+			raise Error, 'sample width not set'
+		return self._sampwidth
+
+	def setframerate(self, framerate):
+		if self._datawritten:
+			raise Error, 'cannot change parameters after starting to write'
+		if framerate <= 0:
+			raise Error, 'bad frame rate'
+		self._framerate = framerate
+
+	def getframerate(self):
+		if not self._framerate:
+			raise Error, 'frame rate not set'
+		return self._framerate
+
+	def setnframes(self, nframes):
+		if self._datawritten:
+			raise Error, 'cannot change parameters after starting to write'
+		self._nframes = nframes
+
+	def getnframes(self):
+		return self._nframeswritten
+
+	def setcomptype(self, comptype, compname):
+		if self._datawritten:
+			raise Error, 'cannot change parameters after starting to write'
+		if comptype not in ('NONE',):
+			raise Error, 'unsupported compression type'
+		self._comptype = comptype
+		self._compname = compname
+
+	def getcomptype(self):
+		return self._comptype
+
+	def getcompname(self):
+		return self._compname
+
+	def setparams(self, (nchannels, sampwidth, framerate, nframes, comptype, compname)):
+		if self._datawritten:
+			raise Error, 'cannot change parameters after starting to write'
+		self.setnchannels(nchannels)
+		self.setsampwidth(sampwidth)
+		self.setframerate(framerate)
+		self.setnframes(nframes)
+		self.setcomptype(comptype, compname)
+
+	def getparams(self):
+		if not self._nchannels or not self._sampwidth or not self._framerate:
+			raise Error, 'not all parameters set'
+		return self._nchannels, self._sampwidth, self._framerate, \
+			  self._nframes, self._comptype, self._compname
+
+	def setmark(self, id, pos, name):
+		raise Error, 'setmark() not supported'
+
+	def getmark(self, id):
+		raise Error, 'no marks'
+
+	def getmarkers(self):
+		return None
+				
+	def tell(self):
+		return self._nframeswritten
+
+	def writeframesraw(self, data):
+		self._ensure_header_written(len(data))
+		nframes = len(data) / (self._sampwidth * self._nchannels)
+		if self._convert:
+			data = self._convert(data)
+		if self._sampwidth > 1:
+			import array
+			data = array.array(_array_fmts[self._sampwidth], data)
+			data.byteswap()
+			data.tofile(self._file)
+			self._datawritten = self._datawritten + len(data) * self._sampwidth
+		else:
+			self._file.write(data)
+			self._datawritten = self._datawritten + len(data)
+		self._nframeswritten = self._nframeswritten + nframes
+
+	def writeframes(self, data):
+		self.writeframesraw(data)
+		if self._datalength != self._datawritten:
+			self._patchheader()
+
+	def close(self):
+		self._ensure_header_written(0)
+		if self._datalength != self._datawritten:
+			self._patchheader()
+		self._file.flush()
+		self._file = None
+
+	#
+	# Internal methods.
+	#
+	access *: private
+
+	def _ensure_header_written(self, datasize):
+		if not self._datawritten:
+			if not self._nchannels:
+				raise Error, '# channels not specified'
+			if not self._sampwidth:
+				raise Error, 'sample width not specified'
+			if not self._framerate:
+				raise Error, 'sampling rate not specified'
+			self._write_header(datasize)
+
+	def _write_header(self, initlength):
+		self._file.write('RIFF')
+		if not self._nframes:
+			self._nframes = initlength / (self._nchannels * self._sampwidth)
+		self._datalength = self._nframes * self._nchannels * self._sampwidth
+		self._form_length_pos = self._file.tell()
+		_write_long(self._file, 36 + self._datalength)
+		self._file.write('WAVE')
+		self._file.write('fmt ')
+		_write_long(self._file, 16)
+		_write_short(self._file, WAVE_FORMAT_PCM)
+		_write_short(self._file, self._nchannels)
+		_write_long(self._file, self._framerate)
+		_write_long(self._file, self._nchannels * self._framerate * self._sampwidth)
+		_write_short(self._file, self._nchannels * self._sampwidth)
+		_write_short(self._file, self._sampwidth * 8)
+		self._file.write('data')
+		self._data_length_pos = self._file.tell()
+		_write_long(self._file, self._datalength)
+
+	def _patchheader(self):
+		if self._datawritten == self._datalength:
+			return
+		curpos = self._file.tell()
+		self._file.seek(self._form_length_pos, 0)
+		_write_long(36 + self._datawritten)
+		self._file.seek(self._data_length_pos, 0)
+		_write_long(self._file, self._datawritten)
+		self._file.seek(curpos, 0)
+		self._datalength = self._datawritten
+
+def open(f, mode):
+	if mode == 'r':
+		return Wave_read(f)
+	elif mode == 'w':
+		return Wave_write(f)
+	else:
+		raise Error, "mode must be 'r' or 'w'"
+
+openfp = open # B/W compatibility