Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 1 | """New I/O library. |
| 2 | |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 3 | This is an early prototype; eventually some of this will be |
| 4 | reimplemented in C and the rest may be turned into a package. |
| 5 | |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 6 | See PEP 3116. |
Guido van Rossum | c819dea | 2007-03-15 18:59:31 +0000 | [diff] [blame] | 7 | |
| 8 | XXX need to default buffer size to 1 if isatty() |
| 9 | XXX need to support 1 meaning line-buffered |
| 10 | XXX change behavior of blocking I/O |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 11 | XXX don't use assert to validate input requirements |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 12 | """ |
| 13 | |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 14 | __author__ = ("Guido van Rossum <guido@python.org>, " |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 15 | "Mike Verdone <mike.verdone@gmail.com>, " |
| 16 | "Mark Russell <mark.russell@zen.co.uk>") |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 17 | |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 18 | __all__ = ["open", "RawIOBase", "FileIO", "SocketIO", "BytesIO", |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 19 | "BufferedReader", "BufferedWriter", "BufferedRWPair", |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 20 | "BufferedRandom"] |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 21 | |
| 22 | import os |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 23 | import sys |
| 24 | import codecs |
| 25 | import warnings |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 26 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 27 | DEFAULT_BUFFER_SIZE = 8 * 1024 # bytes |
| 28 | DEFAULT_MAX_BUFFER_SIZE = 2 * DEFAULT_BUFFER_SIZE |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 29 | |
| 30 | |
| 31 | class BlockingIO(IOError): |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 32 | |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 33 | def __init__(self, errno, strerror, characters_written): |
| 34 | IOError.__init__(self, errno, strerror) |
| 35 | self.characters_written = characters_written |
| 36 | |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 37 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 38 | def open(file, mode="r", buffering=None, *, encoding=None): |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 39 | """Replacement for the built-in open function. |
| 40 | |
| 41 | Args: |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 42 | file: string giving the name of the file to be opened; |
| 43 | or integer file descriptor of the file to be wrapped (*) |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 44 | mode: optional mode string; see below |
| 45 | buffering: optional int >= 0 giving the buffer size; values |
| 46 | can be: 0 = unbuffered, 1 = line buffered, |
| 47 | larger = fully buffered |
| 48 | encoding: optional string giving the text encoding (*must* be given |
| 49 | as a keyword argument) |
| 50 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 51 | (*) If a file descriptor is given, it is closed when the returned |
| 52 | I/O object is closed. If you don't want this to happen, use |
| 53 | os.dup() to create a duplicate file descriptor. |
| 54 | |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 55 | Mode strings characters: |
| 56 | 'r': open for reading (default) |
| 57 | 'w': open for writing, truncating the file first |
| 58 | 'a': open for writing, appending to the end if the file exists |
| 59 | 'b': binary mode |
| 60 | 't': text mode (default) |
| 61 | '+': open a disk file for updating (implies reading and writing) |
Guido van Rossum | 9be5597 | 2007-04-07 02:59:27 +0000 | [diff] [blame] | 62 | 'U': universal newline mode (for backwards compatibility) |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 63 | |
| 64 | Constraints: |
| 65 | - encoding must not be given when a binary mode is given |
| 66 | - buffering must not be zero when a text mode is given |
| 67 | |
| 68 | Returns: |
| 69 | Depending on the mode and buffering arguments, either a raw |
| 70 | binary stream, a buffered binary stream, or a buffered text |
| 71 | stream, open for reading and/or writing. |
| 72 | """ |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 73 | assert isinstance(file, (basestring, int)), repr(file) |
| 74 | assert isinstance(mode, basestring), repr(mode) |
| 75 | assert buffering is None or isinstance(buffering, int), repr(buffering) |
| 76 | assert encoding is None or isinstance(encoding, basestring), repr(encoding) |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 77 | modes = set(mode) |
Guido van Rossum | 9be5597 | 2007-04-07 02:59:27 +0000 | [diff] [blame] | 78 | if modes - set("arwb+tU") or len(mode) > len(modes): |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 79 | raise ValueError("invalid mode: %r" % mode) |
| 80 | reading = "r" in modes |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 81 | writing = "w" in modes |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 82 | appending = "a" in modes |
| 83 | updating = "+" in modes |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 84 | text = "t" in modes |
| 85 | binary = "b" in modes |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 86 | if "U" in modes and not (reading or writing or appending): |
Guido van Rossum | 9be5597 | 2007-04-07 02:59:27 +0000 | [diff] [blame] | 87 | reading = True |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 88 | if text and binary: |
| 89 | raise ValueError("can't have text and binary mode at once") |
| 90 | if reading + writing + appending > 1: |
| 91 | raise ValueError("can't have read/write/append mode at once") |
| 92 | if not (reading or writing or appending): |
| 93 | raise ValueError("must have exactly one of read/write/append mode") |
| 94 | if binary and encoding is not None: |
| 95 | raise ValueError("binary mode doesn't take an encoding") |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 96 | raw = FileIO(file, |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 97 | (reading and "r" or "") + |
| 98 | (writing and "w" or "") + |
| 99 | (appending and "a" or "") + |
| 100 | (updating and "+" or "")) |
| 101 | if buffering is None: |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 102 | buffering = DEFAULT_BUFFER_SIZE |
| 103 | # XXX Should default to line buffering if os.isatty(raw.fileno()) |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 104 | try: |
| 105 | bs = os.fstat(raw.fileno()).st_blksize |
| 106 | except (os.error, AttributeError): |
Guido van Rossum | bb09b21 | 2007-03-18 03:36:28 +0000 | [diff] [blame] | 107 | pass |
| 108 | else: |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 109 | if bs > 1: |
| 110 | buffering = bs |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 111 | if buffering < 0: |
| 112 | raise ValueError("invalid buffering size") |
| 113 | if buffering == 0: |
| 114 | if binary: |
| 115 | return raw |
| 116 | raise ValueError("can't have unbuffered text I/O") |
| 117 | if updating: |
| 118 | buffer = BufferedRandom(raw, buffering) |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 119 | elif writing or appending: |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 120 | buffer = BufferedWriter(raw, buffering) |
| 121 | else: |
| 122 | assert reading |
| 123 | buffer = BufferedReader(raw, buffering) |
| 124 | if binary: |
| 125 | return buffer |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 126 | # XXX What about newline conventions? |
| 127 | textio = TextIOWrapper(buffer, encoding) |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 128 | return textio |
| 129 | |
| 130 | |
| 131 | class RawIOBase: |
| 132 | |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 133 | """Base class for raw binary I/O. |
| 134 | |
| 135 | This class provides dummy implementations for all methods that |
| 136 | derived classes can override selectively; the default |
| 137 | implementations represent a file that cannot be read, written or |
| 138 | seeked. |
| 139 | |
| 140 | The read() method is implemented by calling readinto(); derived |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 141 | classes that want to support read() only need to implement |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 142 | readinto() as a primitive operation. |
| 143 | """ |
| 144 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 145 | def _unsupported(self, name): |
| 146 | raise IOError("%s.%s() not supported" % (self.__class__.__name__, |
| 147 | name)) |
| 148 | |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 149 | def read(self, n): |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 150 | """read(n: int) -> bytes. Read and return up to n bytes. |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 151 | |
| 152 | Returns an empty bytes array on EOF, or None if the object is |
| 153 | set not to block and has no data to read. |
| 154 | """ |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 155 | b = bytes(n.__index__()) |
Guido van Rossum | 00efead | 2007-03-07 05:23:25 +0000 | [diff] [blame] | 156 | n = self.readinto(b) |
| 157 | del b[n:] |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 158 | return b |
| 159 | |
| 160 | def readinto(self, b): |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 161 | """readinto(b: bytes) -> None. Read up to len(b) bytes into b. |
| 162 | |
| 163 | Returns number of bytes read (0 for EOF), or None if the object |
| 164 | is set not to block as has no data to read. |
| 165 | """ |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 166 | self._unsupported("readinto") |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 167 | |
| 168 | def write(self, b): |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 169 | """write(b: bytes) -> int. Write the given buffer to the IO stream. |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 170 | |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 171 | Returns the number of bytes written, which may be less than len(b). |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 172 | """ |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 173 | self._unsupported("write") |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 174 | |
| 175 | def seek(self, pos, whence=0): |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 176 | """seek(pos: int, whence: int = 0) -> None. Change stream position. |
| 177 | |
| 178 | Seek to byte offset pos relative to position indicated by whence: |
| 179 | 0 Start of stream (the default). pos should be >= 0; |
| 180 | 1 Current position - whence may be negative; |
| 181 | 2 End of stream - whence usually negative. |
| 182 | """ |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 183 | self._unsupported("seek") |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 184 | |
| 185 | def tell(self): |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 186 | """tell() -> int. Return current stream position.""" |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 187 | self._unsupported("tell") |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 188 | |
| 189 | def truncate(self, pos=None): |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 190 | """truncate(size: int = None) -> None. Truncate file to size bytes. |
| 191 | |
| 192 | Size defaults to the current IO position as reported by tell(). |
| 193 | """ |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 194 | self._unsupported("truncate") |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 195 | |
| 196 | def close(self): |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 197 | """close() -> None. Close IO object.""" |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 198 | pass |
| 199 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 200 | @property |
| 201 | def closed(self): |
| 202 | """closed: bool. True iff the file has been closed.""" |
| 203 | # This is a property for backwards compatibility |
| 204 | return False |
| 205 | |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 206 | def seekable(self): |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 207 | """seekable() -> bool. Return whether object supports random access. |
| 208 | |
| 209 | If False, seek(), tell() and truncate() will raise IOError. |
| 210 | This method may need to do a test seek(). |
| 211 | """ |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 212 | return False |
| 213 | |
| 214 | def readable(self): |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 215 | """readable() -> bool. Return whether object was opened for reading. |
| 216 | |
| 217 | If False, read() will raise IOError. |
| 218 | """ |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 219 | return False |
| 220 | |
| 221 | def writable(self): |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 222 | """writable() -> bool. Return whether object was opened for writing. |
| 223 | |
| 224 | If False, write() and truncate() will raise IOError. |
| 225 | """ |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 226 | return False |
| 227 | |
| 228 | def __enter__(self): |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 229 | """Context management protocol. Returns self.""" |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 230 | return self |
| 231 | |
| 232 | def __exit__(self, *args): |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 233 | """Context management protocol. Same as close()""" |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 234 | self.close() |
| 235 | |
| 236 | def fileno(self): |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 237 | """fileno() -> int. Return underlying file descriptor if there is one. |
| 238 | |
| 239 | Raises IOError if the IO object does not use a file descriptor. |
| 240 | """ |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 241 | self._unsupported("fileno") |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 242 | |
| 243 | |
Guido van Rossum | a9e2024 | 2007-03-08 00:43:48 +0000 | [diff] [blame] | 244 | class _PyFileIO(RawIOBase): |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 245 | |
| 246 | """Raw I/O implementation for OS files.""" |
| 247 | |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 248 | # XXX More docs |
| 249 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 250 | def __init__(self, file, mode): |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 251 | self._seekable = None |
| 252 | self._mode = mode |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 253 | if isinstance(file, int): |
| 254 | self._fd = file |
| 255 | return |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 256 | if mode == "r": |
| 257 | flags = os.O_RDONLY |
| 258 | elif mode == "w": |
| 259 | flags = os.O_WRONLY | os.O_CREAT | os.O_TRUNC |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 260 | elif mode == "r+": |
| 261 | flags = os.O_RDWR |
| 262 | else: |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 263 | assert False, "unsupported mode %r (for now)" % mode |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 264 | if hasattr(os, "O_BINARY"): |
| 265 | flags |= os.O_BINARY |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 266 | self._fd = os.open(file, flags) |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 267 | |
| 268 | def readinto(self, b): |
| 269 | # XXX We really should have os.readinto() |
Guido van Rossum | 00efead | 2007-03-07 05:23:25 +0000 | [diff] [blame] | 270 | tmp = os.read(self._fd, len(b)) |
| 271 | n = len(tmp) |
| 272 | b[:n] = tmp |
| 273 | return n |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 274 | |
| 275 | def write(self, b): |
| 276 | return os.write(self._fd, b) |
| 277 | |
| 278 | def seek(self, pos, whence=0): |
| 279 | os.lseek(self._fd, pos, whence) |
| 280 | |
| 281 | def tell(self): |
| 282 | return os.lseek(self._fd, 0, 1) |
| 283 | |
| 284 | def truncate(self, pos=None): |
| 285 | if pos is None: |
| 286 | pos = self.tell() |
| 287 | os.ftruncate(self._fd, pos) |
| 288 | |
| 289 | def close(self): |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 290 | # Must be idempotent |
| 291 | # XXX But what about thread-safe? |
| 292 | fd = self._fd |
| 293 | self._fd = -1 |
| 294 | if fd >= 0: |
| 295 | os.close(fd) |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 296 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 297 | @property |
| 298 | def closed(self): |
| 299 | return self._fd >= 0 |
| 300 | |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 301 | def readable(self): |
| 302 | return "r" in self._mode or "+" in self._mode |
| 303 | |
| 304 | def writable(self): |
| 305 | return "w" in self._mode or "+" in self._mode or "a" in self._mode |
| 306 | |
| 307 | def seekable(self): |
| 308 | if self._seekable is None: |
| 309 | try: |
| 310 | os.lseek(self._fd, 0, 1) |
| 311 | except os.error: |
| 312 | self._seekable = False |
| 313 | else: |
| 314 | self._seekable = True |
| 315 | return self._seekable |
| 316 | |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 317 | def fileno(self): |
| 318 | return self._fd |
| 319 | |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 320 | |
Guido van Rossum | a9e2024 | 2007-03-08 00:43:48 +0000 | [diff] [blame] | 321 | try: |
| 322 | import _fileio |
| 323 | except ImportError: |
| 324 | # Let's use the Python version |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 325 | warnings.warn("Can't import _fileio, using slower Python lookalike", |
| 326 | RuntimeWarning) |
Guido van Rossum | a9e2024 | 2007-03-08 00:43:48 +0000 | [diff] [blame] | 327 | FileIO = _PyFileIO |
| 328 | else: |
| 329 | # Create a trivial subclass with the proper inheritance structure |
| 330 | class FileIO(_fileio._FileIO, RawIOBase): |
| 331 | """Raw I/O implementation for OS files.""" |
| 332 | # XXX More docs |
| 333 | |
| 334 | |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 335 | class SocketIO(RawIOBase): |
| 336 | |
| 337 | """Raw I/O implementation for stream sockets.""" |
| 338 | |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 339 | # XXX More docs |
| 340 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 341 | _closed = True |
| 342 | |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 343 | def __init__(self, sock, mode): |
| 344 | assert mode in ("r", "w", "rw") |
| 345 | self._sock = sock |
| 346 | self._mode = mode |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 347 | self._closed = False |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 348 | |
| 349 | def readinto(self, b): |
| 350 | return self._sock.recv_into(b) |
| 351 | |
| 352 | def write(self, b): |
| 353 | return self._sock.send(b) |
| 354 | |
| 355 | def close(self): |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 356 | self._closed = True |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 357 | self._sock.close() |
| 358 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 359 | @property |
| 360 | def closed(self): |
| 361 | return self._closed |
| 362 | |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 363 | def readable(self): |
| 364 | return "r" in self._mode |
| 365 | |
| 366 | def writable(self): |
| 367 | return "w" in self._mode |
| 368 | |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 369 | def fileno(self): |
| 370 | return self._sock.fileno() |
Neal Norwitz | 8b41c3d | 2007-02-27 06:26:14 +0000 | [diff] [blame] | 371 | |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 372 | |
Guido van Rossum | 1866859 | 2007-04-06 18:11:47 +0000 | [diff] [blame] | 373 | class _MemoryIOBase(RawIOBase): |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 374 | |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 375 | # XXX docstring |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 376 | |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 377 | def __init__(self, buffer): |
| 378 | self._buffer = buffer |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 379 | self._pos = 0 |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 380 | |
| 381 | def getvalue(self): |
| 382 | return self._buffer |
| 383 | |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 384 | def read(self, n=None): |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 385 | # XXX Shouldn't this support n < 0 too? |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 386 | if n is None: |
| 387 | n = len(self._buffer) |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 388 | assert n >= 0 |
| 389 | newpos = min(len(self._buffer), self._pos + n) |
| 390 | b = self._buffer[self._pos : newpos] |
| 391 | self._pos = newpos |
| 392 | return b |
| 393 | |
| 394 | def readinto(self, b): |
Guido van Rossum | 00efead | 2007-03-07 05:23:25 +0000 | [diff] [blame] | 395 | tmp = self.read(len(b)) |
| 396 | n = len(tmp) |
| 397 | b[:n] = tmp |
| 398 | return n |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 399 | |
| 400 | def write(self, b): |
| 401 | n = len(b) |
| 402 | newpos = self._pos + n |
| 403 | self._buffer[self._pos:newpos] = b |
| 404 | self._pos = newpos |
| 405 | return n |
| 406 | |
| 407 | def seek(self, pos, whence=0): |
| 408 | if whence == 0: |
| 409 | self._pos = max(0, pos) |
| 410 | elif whence == 1: |
| 411 | self._pos = max(0, self._pos + pos) |
| 412 | elif whence == 2: |
| 413 | self._pos = max(0, len(self._buffer) + pos) |
| 414 | else: |
| 415 | raise IOError("invalid whence value") |
| 416 | |
| 417 | def tell(self): |
| 418 | return self._pos |
| 419 | |
| 420 | def truncate(self, pos=None): |
| 421 | if pos is None: |
| 422 | pos = self._pos |
| 423 | else: |
| 424 | self._pos = max(0, pos) |
| 425 | del self._buffer[pos:] |
| 426 | |
| 427 | def readable(self): |
| 428 | return True |
| 429 | |
| 430 | def writable(self): |
| 431 | return True |
| 432 | |
| 433 | def seekable(self): |
| 434 | return True |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 435 | |
| 436 | |
Guido van Rossum | 1866859 | 2007-04-06 18:11:47 +0000 | [diff] [blame] | 437 | class BytesIO(_MemoryIOBase): |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 438 | |
| 439 | """Buffered I/O implementation using a bytes buffer, like StringIO.""" |
| 440 | |
| 441 | # XXX More docs |
| 442 | |
| 443 | def __init__(self, inital_bytes=None): |
| 444 | buffer = b"" |
| 445 | if inital_bytes is not None: |
| 446 | buffer += inital_bytes |
Guido van Rossum | 1866859 | 2007-04-06 18:11:47 +0000 | [diff] [blame] | 447 | _MemoryIOBase.__init__(self, buffer) |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 448 | |
| 449 | |
Guido van Rossum | 1866859 | 2007-04-06 18:11:47 +0000 | [diff] [blame] | 450 | class StringIO(_MemoryIOBase): |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 451 | |
| 452 | """Buffered I/O implementation using a string buffer, like StringIO.""" |
| 453 | |
| 454 | # XXX More docs |
| 455 | |
| 456 | # XXX Reuses the same code as BytesIO, just with a string rather |
| 457 | # that bytes as the _buffer value. That won't work in C of course. |
| 458 | |
| 459 | def __init__(self, inital_string=None): |
| 460 | buffer = "" |
| 461 | if inital_string is not None: |
| 462 | buffer += inital_string |
Guido van Rossum | 1866859 | 2007-04-06 18:11:47 +0000 | [diff] [blame] | 463 | _MemoryIOBase.__init__(self, buffer) |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 464 | |
| 465 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 466 | # XXX Isn't this the wrong base class? |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 467 | class BufferedIOBase(RawIOBase): |
| 468 | |
| 469 | """Base class for buffered IO objects.""" |
| 470 | |
| 471 | def flush(self): |
| 472 | """Flush the buffer to the underlying raw IO object.""" |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 473 | self._unsupported("flush") |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 474 | |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 475 | def seekable(self): |
| 476 | return self.raw.seekable() |
| 477 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 478 | def fileno(self): |
| 479 | return self.raw.fileno() |
| 480 | |
| 481 | def close(self): |
| 482 | self.raw.close() |
| 483 | |
| 484 | @property |
| 485 | def closed(self): |
| 486 | return self.raw.closed |
| 487 | |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 488 | |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 489 | class BufferedReader(BufferedIOBase): |
| 490 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 491 | """Buffer for a readable sequential RawIO object.""" |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 492 | |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 493 | def __init__(self, raw, buffer_size=DEFAULT_BUFFER_SIZE): |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 494 | """Create a new buffered reader using the given readable raw IO object. |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 495 | """ |
| 496 | assert raw.readable() |
| 497 | self.raw = raw |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 498 | self._read_buf = b"" |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 499 | self.buffer_size = buffer_size |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 500 | |
| 501 | def read(self, n=None): |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 502 | """Read n bytes. |
| 503 | |
| 504 | Returns exactly n bytes of data unless the underlying raw IO |
| 505 | stream reaches EOF of if the call would block in non-blocking |
| 506 | mode. If n is None, read until EOF or until read() would |
| 507 | block. |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 508 | """ |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 509 | # XXX n == 0 should return b""? |
| 510 | # XXX n < 0 should be the same as n is None? |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 511 | assert n is None or n > 0, '.read(): Bad read size %r' % n |
| 512 | nodata_val = b"" |
| 513 | while n is None or len(self._read_buf) < n: |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 514 | to_read = max(self.buffer_size, |
| 515 | n if n is not None else 2*len(self._read_buf)) |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 516 | current = self.raw.read(to_read) |
| 517 | |
| 518 | if current in (b"", None): |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 519 | nodata_val = current |
| 520 | break |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 521 | self._read_buf += current |
| 522 | if self._read_buf: |
| 523 | if n is None: |
| 524 | n = len(self._read_buf) |
| 525 | out = self._read_buf[:n] |
| 526 | self._read_buf = self._read_buf[n:] |
| 527 | else: |
| 528 | out = nodata_val |
| 529 | return out |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 530 | |
| 531 | def readable(self): |
| 532 | return True |
| 533 | |
| 534 | def flush(self): |
| 535 | # Flush is a no-op |
| 536 | pass |
| 537 | |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 538 | def tell(self): |
| 539 | return self.raw.tell() - len(self._read_buf) |
| 540 | |
| 541 | def seek(self, pos, whence=0): |
| 542 | if whence == 1: |
| 543 | pos -= len(self._read_buf) |
| 544 | self.raw.seek(pos, whence) |
| 545 | self._read_buf = b"" |
| 546 | |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 547 | |
| 548 | class BufferedWriter(BufferedIOBase): |
| 549 | |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 550 | # XXX docstring |
| 551 | |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 552 | def __init__(self, raw, buffer_size=DEFAULT_BUFFER_SIZE, |
| 553 | max_buffer_size=DEFAULT_MAX_BUFFER_SIZE): |
| 554 | assert raw.writable() |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 555 | self.raw = raw |
| 556 | self.buffer_size = buffer_size |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 557 | self.max_buffer_size = max_buffer_size |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 558 | self._write_buf = b"" |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 559 | |
| 560 | def write(self, b): |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 561 | # XXX we can implement some more tricks to try and avoid partial writes |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 562 | ##assert issubclass(type(b), bytes) |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 563 | if len(self._write_buf) > self.buffer_size: |
| 564 | # We're full, so let's pre-flush the buffer |
| 565 | try: |
| 566 | self.flush() |
| 567 | except BlockingIO as e: |
| 568 | # We can't accept anything else. |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 569 | # XXX Why not just let the exception pass through? |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 570 | raise BlockingIO(e.errno, e.strerror, 0) |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 571 | self._write_buf.extend(b) |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 572 | if len(self._write_buf) > self.buffer_size: |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 573 | try: |
| 574 | self.flush() |
| 575 | except BlockingIO as e: |
| 576 | if (len(self._write_buf) > self.max_buffer_size): |
| 577 | # We've hit max_buffer_size. We have to accept a partial |
| 578 | # write and cut back our buffer. |
| 579 | overage = len(self._write_buf) - self.max_buffer_size |
| 580 | self._write_buf = self._write_buf[:self.max_buffer_size] |
| 581 | raise BlockingIO(e.errno, e.strerror, overage) |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 582 | |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 583 | def writable(self): |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 584 | return True |
| 585 | |
| 586 | def flush(self): |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 587 | written = 0 |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 588 | try: |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 589 | while self._write_buf: |
| 590 | n = self.raw.write(self._write_buf) |
| 591 | del self._write_buf[:n] |
| 592 | written += n |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 593 | except BlockingIO as e: |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 594 | n = e.characters_written |
| 595 | del self._write_buf[:n] |
| 596 | written += n |
| 597 | raise BlockingIO(e.errno, e.strerror, written) |
| 598 | |
| 599 | def tell(self): |
| 600 | return self.raw.tell() + len(self._write_buf) |
| 601 | |
| 602 | def seek(self, pos, whence=0): |
| 603 | self.flush() |
| 604 | self.raw.seek(pos, whence) |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 605 | |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 606 | def close(self): |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 607 | self.flush() |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 608 | self.raw.close() |
| 609 | |
| 610 | def __del__(self): |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 611 | try: |
| 612 | self.flush() |
| 613 | except: |
| 614 | pass |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 615 | |
| 616 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 617 | # XXX Maybe use containment instead of multiple inheritance? |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 618 | class BufferedRWPair(BufferedReader, BufferedWriter): |
| 619 | |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 620 | """A buffered reader and writer object together. |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 621 | |
| 622 | A buffered reader object and buffered writer object put together to |
| 623 | form a sequential IO object that can read and write. |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 624 | |
| 625 | This is typically used with a socket or two-way pipe. |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 626 | """ |
| 627 | |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 628 | def __init__(self, reader, writer, buffer_size=DEFAULT_BUFFER_SIZE, |
| 629 | max_buffer_size=DEFAULT_MAX_BUFFER_SIZE): |
| 630 | assert reader.readable() |
| 631 | assert writer.writable() |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 632 | BufferedReader.__init__(self, reader, buffer_size) |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 633 | BufferedWriter.__init__(self, writer, buffer_size, max_buffer_size) |
| 634 | self.reader = reader |
| 635 | self.writer = writer |
| 636 | |
| 637 | def read(self, n=None): |
| 638 | return self.reader.read(n) |
| 639 | |
| 640 | def write(self, b): |
| 641 | return self.writer.write(b) |
| 642 | |
| 643 | def readable(self): |
| 644 | return self.reader.readable() |
| 645 | |
| 646 | def writable(self): |
| 647 | return self.writer.writable() |
| 648 | |
| 649 | def flush(self): |
| 650 | return self.writer.flush() |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 651 | |
| 652 | def seekable(self): |
| 653 | return False |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 654 | |
| 655 | def fileno(self): |
| 656 | # XXX whose fileno do we return? Reader's? Writer's? Unsupported? |
| 657 | raise IOError(".fileno() unsupported") |
| 658 | |
| 659 | def close(self): |
| 660 | self.reader.close() |
| 661 | self.writer.close() |
| 662 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 663 | @property |
| 664 | def closed(self): |
| 665 | return self.reader.closed or self.writer.closed |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 666 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 667 | |
| 668 | # XXX Maybe use containment instead of multiple inheritance? |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 669 | class BufferedRandom(BufferedReader, BufferedWriter): |
| 670 | |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 671 | # XXX docstring |
| 672 | |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 673 | def __init__(self, raw, buffer_size=DEFAULT_BUFFER_SIZE, |
| 674 | max_buffer_size=DEFAULT_MAX_BUFFER_SIZE): |
| 675 | assert raw.seekable() |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 676 | BufferedReader.__init__(self, raw, buffer_size) |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 677 | BufferedWriter.__init__(self, raw, buffer_size, max_buffer_size) |
| 678 | |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 679 | def readable(self): |
| 680 | return self.raw.readable() |
| 681 | |
| 682 | def writable(self): |
| 683 | return self.raw.writable() |
| 684 | |
| 685 | def seek(self, pos, whence=0): |
| 686 | self.flush() |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 687 | # First do the raw seek, then empty the read buffer, so that |
| 688 | # if the raw seek fails, we don't lose buffered data forever. |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 689 | self.raw.seek(pos, whence) |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 690 | self._read_buf = b"" |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 691 | # XXX I suppose we could implement some magic here to move through the |
| 692 | # existing read buffer in the case of seek(<some small +ve number>, 1) |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 693 | # XXX OTOH it might be good to *guarantee* that the buffer is |
| 694 | # empty after a seek or flush; for small relative forward |
| 695 | # seeks one might as well use small reads instead. |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 696 | |
| 697 | def tell(self): |
| 698 | if (self._write_buf): |
| 699 | return self.raw.tell() + len(self._write_buf) |
| 700 | else: |
| 701 | return self.raw.tell() - len(self._read_buf) |
| 702 | |
| 703 | def read(self, n=None): |
| 704 | self.flush() |
| 705 | return BufferedReader.read(self, n) |
| 706 | |
| 707 | def write(self, b): |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 708 | if self._read_buf: |
| 709 | self.raw.seek(-len(self._read_buf), 1) # Undo readahead |
| 710 | self._read_buf = b"" |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 711 | return BufferedWriter.write(self, b) |
| 712 | |
| 713 | def flush(self): |
| 714 | BufferedWriter.flush(self) |
| 715 | |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 716 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 717 | # XXX That's not the right base class |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 718 | class TextIOBase(BufferedIOBase): |
| 719 | |
| 720 | """Base class for text I/O. |
| 721 | |
| 722 | This class provides a character and line based interface to stream I/O. |
| 723 | """ |
| 724 | |
| 725 | def read(self, n: int = -1) -> str: |
| 726 | """read(n: int = -1) -> str. Read at most n characters from stream. |
| 727 | |
| 728 | Read from underlying buffer until we have n characters or we hit EOF. |
| 729 | If n is negative or omitted, read until EOF. |
| 730 | """ |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 731 | self._unsupported("read") |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 732 | |
| 733 | def write(self, s: str): |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 734 | """write(s: str) -> None. Write string s to stream.""" |
| 735 | self._unsupported("write") |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 736 | |
| 737 | def readline(self) -> str: |
| 738 | """readline() -> str. Read until newline or EOF. |
| 739 | |
| 740 | Returns an empty string if EOF is hit immediately. |
| 741 | """ |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 742 | self._unsupported("readline") |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 743 | |
| 744 | def __iter__(self): |
| 745 | """__iter__() -> Iterator. Return line iterator (actually just self). |
| 746 | """ |
| 747 | return self |
| 748 | |
| 749 | def next(self): |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 750 | """Same as readline() except raises StopIteration on immediate EOF.""" |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 751 | line = self.readline() |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 752 | if not line: |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 753 | raise StopIteration |
| 754 | return line |
| 755 | |
Guido van Rossum | 9be5597 | 2007-04-07 02:59:27 +0000 | [diff] [blame] | 756 | # The following are provided for backwards compatibility |
| 757 | |
| 758 | def readlines(self, hint=None): |
| 759 | if hint is None: |
| 760 | return list(self) |
| 761 | n = 0 |
| 762 | lines = [] |
| 763 | while not lines or n < hint: |
| 764 | line = self.readline() |
| 765 | if not line: |
| 766 | break |
| 767 | lines.append(line) |
| 768 | n += len(line) |
| 769 | return lines |
| 770 | |
| 771 | def writelines(self, lines): |
| 772 | for line in lines: |
| 773 | self.write(line) |
| 774 | |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 775 | |
| 776 | class TextIOWrapper(TextIOBase): |
| 777 | |
| 778 | """Buffered text stream. |
| 779 | |
| 780 | Character and line based layer over a BufferedIOBase object. |
| 781 | """ |
| 782 | |
| 783 | # XXX tell(), seek() |
| 784 | |
| 785 | def __init__(self, buffer, encoding=None, newline=None): |
| 786 | if newline not in (None, '\n', '\r\n'): |
| 787 | raise IOError("illegal newline %s" % newline) # XXX: ValueError? |
| 788 | if encoding is None: |
| 789 | # XXX This is questionable |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 790 | encoding = sys.getfilesystemencoding() or "latin-1" |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 791 | |
| 792 | self.buffer = buffer |
| 793 | self._encoding = encoding |
| 794 | self._newline = newline or os.linesep |
| 795 | self._fix_newlines = newline is None |
| 796 | self._decoder = None |
| 797 | self._pending = '' |
| 798 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 799 | def flush(self): |
| 800 | self.buffer.flush() |
| 801 | |
| 802 | def close(self): |
| 803 | self.flush() |
| 804 | self.buffer.close() |
| 805 | |
| 806 | @property |
| 807 | def closed(self): |
| 808 | return self.buffer.closed |
| 809 | |
| 810 | def __del__(self): |
| 811 | try: |
| 812 | self.flush() |
| 813 | except: |
| 814 | pass |
| 815 | |
Guido van Rossum | 9be5597 | 2007-04-07 02:59:27 +0000 | [diff] [blame] | 816 | def fileno(self): |
| 817 | return self.buffer.fileno() |
| 818 | |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 819 | def write(self, s: str): |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 820 | b = s.encode(self._encoding) |
| 821 | if isinstance(b, str): |
| 822 | b = bytes(b) |
| 823 | n = self.buffer.write(b) |
| 824 | if "\n" in s: |
| 825 | self.flush() |
| 826 | return n |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 827 | |
| 828 | def _get_decoder(self): |
| 829 | make_decoder = codecs.getincrementaldecoder(self._encoding) |
| 830 | if make_decoder is None: |
| 831 | raise IOError(".readline() not supported for encoding %s" % |
| 832 | self._encoding) |
| 833 | decoder = self._decoder = make_decoder() # XXX: errors |
| 834 | if isinstance(decoder, codecs.BufferedIncrementalDecoder): |
| 835 | # XXX Hack: make the codec use bytes instead of strings |
| 836 | decoder.buffer = b"" |
| 837 | return decoder |
| 838 | |
| 839 | def read(self, n: int = -1): |
| 840 | decoder = self._decoder or self._get_decoder() |
| 841 | res = self._pending |
| 842 | if n < 0: |
| 843 | res += decoder.decode(self.buffer.read(), True) |
| 844 | self._pending = '' |
| 845 | return res |
| 846 | else: |
| 847 | while len(res) < n: |
| 848 | data = self.buffer.read(64) |
| 849 | res += decoder.decode(data, not data) |
| 850 | if not data: |
| 851 | break |
| 852 | self._pending = res[n:] |
| 853 | return res[:n] |
| 854 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 855 | def readline(self, limit=None): |
| 856 | if limit is not None: |
| 857 | # XXX Hack to support limit arg |
| 858 | line = self.readline() |
| 859 | if len(line) <= limit: |
| 860 | return line |
| 861 | line, self._pending = line[:limit], line[limit:] + self._pending |
| 862 | return line |
| 863 | |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 864 | line = self._pending |
| 865 | start = 0 |
| 866 | decoder = self._decoder or self._get_decoder() |
| 867 | |
| 868 | while True: |
| 869 | # In C we'd look for these in parallel of course. |
| 870 | nlpos = line.find("\n", start) |
| 871 | crpos = line.find("\r", start) |
| 872 | if nlpos >= 0 and crpos >= 0: |
| 873 | endpos = min(nlpos, crpos) |
| 874 | else: |
| 875 | endpos = nlpos if nlpos >= 0 else crpos |
| 876 | |
| 877 | if endpos != -1: |
| 878 | endc = line[endpos] |
| 879 | if endc == "\n": |
| 880 | ending = "\n" |
| 881 | break |
| 882 | |
| 883 | # We've seen \r - is it standalone, \r\n or \r at end of line? |
| 884 | if endpos + 1 < len(line): |
| 885 | if line[endpos+1] == '\n': |
| 886 | ending = "\r\n" |
| 887 | else: |
| 888 | ending = "\r" |
| 889 | break |
| 890 | # There might be a following \n in the next block of data ... |
| 891 | start = endpos |
| 892 | else: |
| 893 | start = len(line) |
| 894 | |
| 895 | # No line ending seen yet - get more data |
| 896 | while True: |
| 897 | data = self.buffer.read(64) |
| 898 | more_line = decoder.decode(data, not data) |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 899 | if more_line or not data: |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 900 | break |
| 901 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 902 | if not more_line: |
| 903 | ending = "" |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 904 | endpos = len(line) |
| 905 | break |
| 906 | |
| 907 | line += more_line |
| 908 | |
| 909 | nextpos = endpos + len(ending) |
| 910 | self._pending = line[nextpos:] |
| 911 | |
| 912 | # XXX Update self.newlines here if we want to support that |
| 913 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame^] | 914 | if self._fix_newlines and ending not in ("\n", ""): |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 915 | return line[:endpos] + "\n" |
| 916 | else: |
| 917 | return line[:nextpos] |