diff options
Diffstat (limited to 'tests/bytecode/pylib-tests/bz2.py')
| -rw-r--r-- | tests/bytecode/pylib-tests/bz2.py | 504 |
1 files changed, 0 insertions, 504 deletions
diff --git a/tests/bytecode/pylib-tests/bz2.py b/tests/bytecode/pylib-tests/bz2.py deleted file mode 100644 index 6a4fd505b0..0000000000 --- a/tests/bytecode/pylib-tests/bz2.py +++ /dev/null @@ -1,504 +0,0 @@ -"""Interface to the libbzip2 compression library. - -This module provides a file interface, classes for incremental -(de)compression, and functions for one-shot (de)compression. -""" - -__all__ = ["BZ2File", "BZ2Compressor", "BZ2Decompressor", - "open", "compress", "decompress"] - -__author__ = "Nadeem Vawda <nadeem.vawda@gmail.com>" - -import builtins -import io -import warnings - -try: - from threading import RLock -except ImportError: - from dummy_threading import RLock - -from _bz2 import BZ2Compressor, BZ2Decompressor - - -_MODE_CLOSED = 0 -_MODE_READ = 1 -_MODE_READ_EOF = 2 -_MODE_WRITE = 3 - -_BUFFER_SIZE = 8192 - - -class BZ2File(io.BufferedIOBase): - - """A file object providing transparent bzip2 (de)compression. - - A BZ2File can act as a wrapper for an existing file object, or refer - directly to a named file on disk. - - Note that BZ2File provides a *binary* file interface - data read is - returned as bytes, and data to be written should be given as bytes. - """ - - def __init__(self, filename, mode="r", buffering=None, compresslevel=9): - """Open a bzip2-compressed file. - - If filename is a str or bytes object, is gives the name of the file to - be opened. Otherwise, it should be a file object, which will be used to - read or write the compressed data. - - mode can be 'r' for reading (default), 'w' for (over)writing, or 'a' for - appending. These can equivalently be given as 'rb', 'wb', and 'ab'. - - buffering is ignored. Its use is deprecated. - - If mode is 'w' or 'a', compresslevel can be a number between 1 - and 9 specifying the level of compression: 1 produces the least - compression, and 9 (default) produces the most compression. - - If mode is 'r', the input file may be the concatenation of - multiple compressed streams. - """ - # This lock must be recursive, so that BufferedIOBase's - # readline(), readlines() and writelines() don't deadlock. - self._lock = RLock() - self._fp = None - self._closefp = False - self._mode = _MODE_CLOSED - self._pos = 0 - self._size = -1 - - if buffering is not None: - warnings.warn("Use of 'buffering' argument is deprecated", - DeprecationWarning) - - if not (1 <= compresslevel <= 9): - raise ValueError("compresslevel must be between 1 and 9") - - if mode in (0+"", "r", "rb"): - mode = "rb" - mode_code = _MODE_READ - self._decompressor = BZ2Decompressor() - self._buffer = b"" - self._buffer_offset = 0 - elif mode in (0+"w", "wb"): - mode = "wb" - mode_code = _MODE_WRITE - self._compressor = BZ2Compressor(compresslevel) - elif mode in (0+"a", "ab"): - mode = "ab" - mode_code = _MODE_WRITE - self._compressor = BZ2Compressor(compresslevel) - else: - raise ValueError("Invalid mode: {!r}".format(mode)) - - if isinstance(filename, (str, bytes)): - self._fp = builtins.open(filename, mode) - self._closefp = True - self._mode = mode_code - elif hasattr(filename, "read") or hasattr(filename, "write"): - self._fp = filename - self._mode = mode_code - else: - raise TypeError("filename must be a str or bytes object, or a file") - - def close(self): - """Flush and close the file. - - May be called more than once without error. Once the file is - closed, any other operation on it will raise a ValueError. - """ - with self._lock: - if self._mode == _MODE_CLOSED: - return - try: - if self._mode in (_MODE_READ, _MODE_READ_EOF): - self._decompressor = None - elif self._mode == _MODE_WRITE: - self._fp.write(self._compressor.flush()) - self._compressor = None - finally: - try: - if self._closefp: - self._fp.close() - finally: - self._fp = None - self._closefp = False - self._mode = _MODE_CLOSED - self._buffer = b"" - self._buffer_offset = 0 - - @property - def closed(self): - """True if this file is closed.""" - return self._mode == _MODE_CLOSED - - def fileno(self): - """Return the file descriptor for the underlying file.""" - self._check_not_closed() - return self._fp.fileno() - - def seekable(self): - """Return whether the file supports seeking.""" - return self.readable() and self._fp.seekable() - - def readable(self): - """Return whether the file was opened for reading.""" - self._check_not_closed() - return self._mode in (_MODE_READ, _MODE_READ_EOF) - - def writable(self): - """Return whether the file was opened for writing.""" - self._check_not_closed() - return self._mode == _MODE_WRITE - - # Mode-checking helper functions. - - def _check_not_closed(self): - if self.closed: - raise ValueError("I/O operation on closed file") - - def _check_can_read(self): - if self._mode not in (_MODE_READ, _MODE_READ_EOF): - self._check_not_closed() - raise io.UnsupportedOperation("File not open for reading") - - def _check_can_write(self): - if self._mode != _MODE_WRITE: - self._check_not_closed() - raise io.UnsupportedOperation("File not open for writing") - - def _check_can_seek(self): - if self._mode not in (_MODE_READ, _MODE_READ_EOF): - self._check_not_closed() - raise io.UnsupportedOperation("Seeking is only supported " - "on files open for reading") - if not self._fp.seekable(): - raise io.UnsupportedOperation("The underlying file object " - "does not support seeking") - - # Fill the readahead buffer if it is empty. Returns False on EOF. - def _fill_buffer(self): - if self._mode == _MODE_READ_EOF: - return False - # Depending on the input data, our call to the decompressor may not - # return any data. In this case, try again after reading another block. - while self._buffer_offset == len(self._buffer): - rawblock = (self._decompressor.unused_data or - self._fp.read(_BUFFER_SIZE)) - - if not rawblock: - if self._decompressor.eof: - self._mode = _MODE_READ_EOF - self._size = self._pos - return False - else: - raise EOFError("Compressed file ended before the " - "end-of-stream marker was reached") - - # Continue to next stream. - if self._decompressor.eof: - self._decompressor = BZ2Decompressor() - - self._buffer = self._decompressor.decompress(rawblock) - self._buffer_offset = 0 - return True - - # Read data until EOF. - # If return_data is false, consume the data without returning it. - def _read_all(self, return_data=True): - # The loop assumes that _buffer_offset is 0. Ensure that this is true. - self._buffer = self._buffer[self._buffer_offset:] - self._buffer_offset = 0 - - blocks = [] - while self._fill_buffer(): - if return_data: - blocks.append(self._buffer) - self._pos += len(self._buffer) - self._buffer = b"" - if return_data: - return b"".join(blocks) - - # Read a block of up to n bytes. - # If return_data is false, consume the data without returning it. - def _read_block(self, n, return_data=True): - # If we have enough data buffered, return immediately. - end = self._buffer_offset + n - if end <= len(self._buffer): - data = self._buffer[self._buffer_offset : end] - self._buffer_offset = end - self._pos += len(data) - return data if return_data else None - - # The loop assumes that _buffer_offset is 0. Ensure that this is true. - self._buffer = self._buffer[self._buffer_offset:] - self._buffer_offset = 0 - - blocks = [] - while n > 0 and self._fill_buffer(): - if n < len(self._buffer): - data = self._buffer[:n] - self._buffer_offset = n - else: - data = self._buffer - self._buffer = b"" - if return_data: - blocks.append(data) - self._pos += len(data) - n -= len(data) - if return_data: - return b"".join(blocks) - - def peek(self, n=0): - """Return buffered data without advancing the file position. - - Always returns at least one byte of data, unless at EOF. - The exact number of bytes returned is unspecified. - """ - with self._lock: - self._check_can_read() - if not self._fill_buffer(): - return b"" - return self._buffer[self._buffer_offset:] - - def read(self, size=-1): - """Read up to size uncompressed bytes from the file. - - If size is negative or omitted, read until EOF is reached. - Returns b'' if the file is already at EOF. - """ - with self._lock: - self._check_can_read() - if size == 0: - return b"" - elif size < 0: - return self._read_all() - else: - return self._read_block(size) - - def read1(self, size=-1): - """Read up to size uncompressed bytes, while trying to avoid - making multiple reads from the underlying stream. - - Returns b'' if the file is at EOF. - """ - # Usually, read1() calls _fp.read() at most once. However, sometimes - # this does not give enough data for the decompressor to make progress. - # In this case we make multiple reads, to avoid returning b"". - with self._lock: - self._check_can_read() - if (size == 0 or - # Only call _fill_buffer() if the buffer is actually empty. - # This gives a significant speedup if *size* is small. - (self._buffer_offset == len(self._buffer) and self._fill_buffer())): - return b"" - if size > 0: - data = self._buffer[self._buffer_offset : - self._buffer_offset + size] - self._buffer_offset += len(data) - else: - data = self._buffer[self._buffer_offset:] - self._buffer = b"" - self._buffer_offset = 0 - self._pos += len(data) - return data - - def readinto(self, b): - """Read up to len(b) bytes into b. - - Returns the number of bytes read (0 for EOF). - """ - with self._lock: - return io.BufferedIOBase.readinto(self, b) - - def readline(self, size=-1): - """Read a line of uncompressed bytes from the file. - - The terminating newline (if present) is retained. If size is - non-negative, no more than size bytes will be read (in which - case the line may be incomplete). Returns b'' if already at EOF. - """ - if not isinstance(size, int): - if not hasattr(size, "__index__"): - raise TypeError("Integer argument expected") - size = size.__index__() - with self._lock: - self._check_can_read() - # Shortcut for the common case - the whole line is in the buffer. - if size < 0: - end = self._buffer.find(b"\n", self._buffer_offset) + 1 - if end > 0: - line = self._buffer[self._buffer_offset : end] - self._buffer_offset = end - self._pos += len(line) - return line - return io.BufferedIOBase.readline(self, size) - - def readlines(self, size=-1): - """Read a list of lines of uncompressed bytes from the file. - - size can be specified to control the number of lines read: no - further lines will be read once the total size of the lines read - so far equals or exceeds size. - """ - if not isinstance(size, int): - if not hasattr(size, "__index__"): - raise TypeError("Integer argument expected") - size = size.__index__() - with self._lock: - return io.BufferedIOBase.readlines(self, size) - - def write(self, data): - """Write a byte string to the file. - - Returns the number of uncompressed bytes written, which is - always len(data). Note that due to buffering, the file on disk - may not reflect the data written until close() is called. - """ - with self._lock: - self._check_can_write() - compressed = self._compressor.compress(data) - self._fp.write(compressed) - self._pos += len(data) - return len(data) - - def writelines(self, seq): - """Write a sequence of byte strings to the file. - - Returns the number of uncompressed bytes written. - seq can be any iterable yielding byte strings. - - Line separators are not added between the written byte strings. - """ - with self._lock: - return io.BufferedIOBase.writelines(self, seq) - - # Rewind the file to the beginning of the data stream. - def _rewind(self): - self._fp.seek(0, 0) - self._mode = _MODE_READ - self._pos = 0 - self._decompressor = BZ2Decompressor() - self._buffer = b"" - self._buffer_offset = 0 - - def seek(self, offset, whence=0): - """Change the file position. - - The new position is specified by offset, relative to the - position indicated by whence. Values for whence are: - - 0: start of stream (default); offset must not be negative - 1: current stream position - 2: end of stream; offset must not be positive - - Returns the new file position. - - Note that seeking is emulated, so depending on the parameters, - this operation may be extremely slow. - """ - with self._lock: - self._check_can_seek() - - # Recalculate offset as an absolute file position. - if whence == 0: - pass - elif whence == 1: - offset = self._pos + offset - elif whence == 2: - # Seeking relative to EOF - we need to know the file's size. - if self._size < 0: - self._read_all(return_data=False) - offset = self._size + offset - else: - raise ValueError("Invalid value for whence: {}".format(whence)) - - # Make it so that offset is the number of bytes to skip forward. - if offset < self._pos: - self._rewind() - else: - offset -= self._pos - - # Read and discard data until we reach the desired position. - self._read_block(offset, return_data=False) - - return self._pos - - def tell(self): - """Return the current file position.""" - with self._lock: - self._check_not_closed() - return self._pos - - -def open(filename, mode="rb", compresslevel=9, - encoding=None, errors=None, newline=None): - """Open a bzip2-compressed file in binary or text mode. - - The filename argument can be an actual filename (a str or bytes object), or - an existing file object to read from or write to. - - The mode argument can be "r", "rb", "w", "wb", "a" or "ab" for binary mode, - or "rt", "wt" or "at" for text mode. The default mode is "rb", and the - default compresslevel is 9. - - For binary mode, this function is equivalent to the BZ2File constructor: - BZ2File(filename, mode, compresslevel). In this case, the encoding, errors - and newline arguments must not be provided. - - For text mode, a BZ2File object is created, and wrapped in an - io.TextIOWrapper instance with the specified encoding, error handling - behavior, and line ending(s). - - """ - if "t" in mode: - if "b" in mode: - raise ValueError("Invalid mode: %r" % (mode,)) - else: - if encoding is not None: - raise ValueError("Argument 'encoding' not supported in binary mode") - if errors is not None: - raise ValueError("Argument 'errors' not supported in binary mode") - if newline is not None: - raise ValueError("Argument 'newline' not supported in binary mode") - - bz_mode = mode.replace("t", "") - binary_file = BZ2File(filename, bz_mode, compresslevel=compresslevel) - - if "t" in mode: - return io.TextIOWrapper(binary_file, encoding, errors, newline) - else: - return binary_file - - -def compress(data, compresslevel=9): - """Compress a block of data. - - compresslevel, if given, must be a number between 1 and 9. - - For incremental compression, use a BZ2Compressor object instead. - """ - comp = BZ2Compressor(compresslevel) - return comp.compress(data) + comp.flush() - - -def decompress(data): - """Decompress a block of data. - - For incremental decompression, use a BZ2Decompressor object instead. - """ - if len(data) == 0: - return b"" - - results = [] - while True: - decomp = BZ2Decompressor() - results.append(decomp.decompress(data)) - if not decomp.eof: - raise ValueError("Compressed data ended before the " - "end-of-stream marker was reached") - if not decomp.unused_data: - return b"".join(results) - # There is unused data left over. Proceed to next stream. - data = decomp.unused_data |