Guido van Rossum | 53807da | 2007-04-10 19:01:47 +0000 | [diff] [blame] | 1 | """New I/O library conforming to PEP 3116. |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 2 | |
Guido van Rossum | b9c4c3e | 2007-04-11 16:07:50 +0000 | [diff] [blame] | 3 | This is a prototype; hopefully eventually some of this will be |
| 4 | reimplemented in C. |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 5 | |
Guido van Rossum | 53807da | 2007-04-10 19:01:47 +0000 | [diff] [blame] | 6 | Conformance of alternative implementations: all arguments are intended |
| 7 | to be positional-only except the arguments of the open() function. |
| 8 | Argument names except those of the open() function are not part of the |
| 9 | specification. Instance variables and methods whose name starts with |
| 10 | a leading underscore are not part of the specification (except "magic" |
| 11 | names like __iter__). Only the top-level names listed in the __all__ |
| 12 | variable are part of the specification. |
Guido van Rossum | c819dea | 2007-03-15 18:59:31 +0000 | [diff] [blame] | 13 | |
Guido van Rossum | b9c4c3e | 2007-04-11 16:07:50 +0000 | [diff] [blame] | 14 | XXX edge cases when switching between reading/writing |
Guido van Rossum | c819dea | 2007-03-15 18:59:31 +0000 | [diff] [blame] | 15 | XXX need to support 1 meaning line-buffered |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 16 | XXX whenever an argument is None, use the default value |
| 17 | XXX read/write ops should check readable/writable |
Guido van Rossum | d410395 | 2007-04-12 05:44:49 +0000 | [diff] [blame] | 18 | XXX buffered readinto should work with arbitrary buffer objects |
Guido van Rossum | d76e779 | 2007-04-17 02:38:04 +0000 | [diff] [blame] | 19 | XXX use incremental encoder for text output, at least for UTF-16 and UTF-8-SIG |
Guido van Rossum | 5abbf75 | 2007-08-27 17:39:33 +0000 | [diff] [blame] | 20 | XXX check writable, readable and seekable in appropriate places |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 21 | """ |
| 22 | |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 23 | __author__ = ("Guido van Rossum <guido@python.org>, " |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 24 | "Mike Verdone <mike.verdone@gmail.com>, " |
| 25 | "Mark Russell <mark.russell@zen.co.uk>") |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 26 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 27 | __all__ = ["BlockingIOError", "open", "IOBase", "RawIOBase", "FileIO", |
Guido van Rossum | 5abbf75 | 2007-08-27 17:39:33 +0000 | [diff] [blame] | 28 | "BytesIO", "StringIO", "BufferedIOBase", |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 29 | "BufferedReader", "BufferedWriter", "BufferedRWPair", |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 30 | "BufferedRandom", "TextIOBase", "TextIOWrapper"] |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 31 | |
| 32 | import os |
Guido van Rossum | b7f136e | 2007-08-22 18:14:10 +0000 | [diff] [blame] | 33 | import abc |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 34 | import sys |
| 35 | import codecs |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 36 | import _fileio |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 37 | import warnings |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 38 | |
Guido van Rossum | 5abbf75 | 2007-08-27 17:39:33 +0000 | [diff] [blame] | 39 | # open() uses st_blksize whenever we can |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 40 | DEFAULT_BUFFER_SIZE = 8 * 1024 # bytes |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 41 | |
| 42 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 43 | class BlockingIOError(IOError): |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 44 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 45 | """Exception raised when I/O would block on a non-blocking I/O stream.""" |
| 46 | |
| 47 | def __init__(self, errno, strerror, characters_written=0): |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 48 | IOError.__init__(self, errno, strerror) |
| 49 | self.characters_written = characters_written |
| 50 | |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 51 | |
Guido van Rossum | 9cbfffd | 2007-06-07 00:54:15 +0000 | [diff] [blame] | 52 | def open(file, mode="r", buffering=None, encoding=None, newline=None): |
Brett Cannon | 7648ba8 | 2007-10-15 20:52:41 +0000 | [diff] [blame] | 53 | r"""Replacement for the built-in open function. |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 54 | |
| 55 | Args: |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 56 | file: string giving the name of the file to be opened; |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 57 | or integer file descriptor of the file to be wrapped (*). |
| 58 | mode: optional mode string; see below. |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 59 | buffering: optional int >= 0 giving the buffer size; values |
| 60 | can be: 0 = unbuffered, 1 = line buffered, |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 61 | larger = fully buffered. |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 62 | encoding: optional string giving the text encoding. |
Guido van Rossum | 8358db2 | 2007-08-18 21:39:55 +0000 | [diff] [blame] | 63 | newline: optional newlines specifier; must be None, '', '\n', '\r' |
| 64 | or '\r\n'; all other values are illegal. It controls the |
| 65 | handling of line endings. It works as follows: |
| 66 | |
| 67 | * On input, if `newline` is `None`, universal newlines |
| 68 | mode is enabled. Lines in the input can end in `'\n'`, |
| 69 | `'\r'`, or `'\r\n'`, and these are translated into |
| 70 | `'\n'` before being returned to the caller. If it is |
| 71 | `''`, universal newline mode is enabled, but line endings |
| 72 | are returned to the caller untranslated. If it has any of |
| 73 | the other legal values, input lines are only terminated by |
| 74 | the given string, and the line ending is returned to the |
| 75 | caller untranslated. |
| 76 | |
| 77 | * On output, if `newline` is `None`, any `'\n'` |
| 78 | characters written are translated to the system default |
| 79 | line separator, `os.linesep`. If `newline` is `''`, |
| 80 | no translation takes place. If `newline` is any of the |
| 81 | other legal values, any `'\n'` characters written are |
| 82 | translated to the given string. |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 83 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 84 | (*) If a file descriptor is given, it is closed when the returned |
| 85 | I/O object is closed. If you don't want this to happen, use |
| 86 | os.dup() to create a duplicate file descriptor. |
| 87 | |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 88 | Mode strings characters: |
| 89 | 'r': open for reading (default) |
| 90 | 'w': open for writing, truncating the file first |
| 91 | 'a': open for writing, appending to the end if the file exists |
| 92 | 'b': binary mode |
| 93 | 't': text mode (default) |
| 94 | '+': open a disk file for updating (implies reading and writing) |
Guido van Rossum | 9be5597 | 2007-04-07 02:59:27 +0000 | [diff] [blame] | 95 | 'U': universal newline mode (for backwards compatibility) |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 96 | |
| 97 | Constraints: |
| 98 | - encoding must not be given when a binary mode is given |
| 99 | - buffering must not be zero when a text mode is given |
| 100 | |
| 101 | Returns: |
| 102 | Depending on the mode and buffering arguments, either a raw |
| 103 | binary stream, a buffered binary stream, or a buffered text |
| 104 | stream, open for reading and/or writing. |
| 105 | """ |
Guido van Rossum | 3172c5d | 2007-10-16 18:12:55 +0000 | [diff] [blame] | 106 | if not isinstance(file, (str, int)): |
Guido van Rossum | 5abbf75 | 2007-08-27 17:39:33 +0000 | [diff] [blame] | 107 | raise TypeError("invalid file: %r" % file) |
Guido van Rossum | 3172c5d | 2007-10-16 18:12:55 +0000 | [diff] [blame] | 108 | if not isinstance(mode, str): |
Guido van Rossum | 5abbf75 | 2007-08-27 17:39:33 +0000 | [diff] [blame] | 109 | raise TypeError("invalid mode: %r" % mode) |
| 110 | if buffering is not None and not isinstance(buffering, int): |
| 111 | raise TypeError("invalid buffering: %r" % buffering) |
Guido van Rossum | 3172c5d | 2007-10-16 18:12:55 +0000 | [diff] [blame] | 112 | if encoding is not None and not isinstance(encoding, str): |
Guido van Rossum | 5abbf75 | 2007-08-27 17:39:33 +0000 | [diff] [blame] | 113 | raise TypeError("invalid encoding: %r" % encoding) |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 114 | modes = set(mode) |
Guido van Rossum | 9be5597 | 2007-04-07 02:59:27 +0000 | [diff] [blame] | 115 | if modes - set("arwb+tU") or len(mode) > len(modes): |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 116 | raise ValueError("invalid mode: %r" % mode) |
| 117 | reading = "r" in modes |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 118 | writing = "w" in modes |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 119 | appending = "a" in modes |
| 120 | updating = "+" in modes |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 121 | text = "t" in modes |
| 122 | binary = "b" in modes |
Guido van Rossum | 7165cb1 | 2007-07-10 06:54:34 +0000 | [diff] [blame] | 123 | if "U" in modes: |
| 124 | if writing or appending: |
| 125 | raise ValueError("can't use U and writing mode at once") |
Guido van Rossum | 9be5597 | 2007-04-07 02:59:27 +0000 | [diff] [blame] | 126 | reading = True |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 127 | if text and binary: |
| 128 | raise ValueError("can't have text and binary mode at once") |
| 129 | if reading + writing + appending > 1: |
| 130 | raise ValueError("can't have read/write/append mode at once") |
| 131 | if not (reading or writing or appending): |
| 132 | raise ValueError("must have exactly one of read/write/append mode") |
| 133 | if binary and encoding is not None: |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 134 | raise ValueError("binary mode doesn't take an encoding argument") |
| 135 | if binary and newline is not None: |
| 136 | raise ValueError("binary mode doesn't take a newline argument") |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 137 | raw = FileIO(file, |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 138 | (reading and "r" or "") + |
| 139 | (writing and "w" or "") + |
| 140 | (appending and "a" or "") + |
| 141 | (updating and "+" or "")) |
| 142 | if buffering is None: |
Guido van Rossum | c2f93dc | 2007-05-24 00:50:02 +0000 | [diff] [blame] | 143 | buffering = -1 |
Guido van Rossum | 5abbf75 | 2007-08-27 17:39:33 +0000 | [diff] [blame] | 144 | if buffering < 0 and raw.isatty(): |
| 145 | buffering = 1 |
Guido van Rossum | c2f93dc | 2007-05-24 00:50:02 +0000 | [diff] [blame] | 146 | if buffering < 0: |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 147 | buffering = DEFAULT_BUFFER_SIZE |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 148 | try: |
| 149 | bs = os.fstat(raw.fileno()).st_blksize |
| 150 | except (os.error, AttributeError): |
Guido van Rossum | bb09b21 | 2007-03-18 03:36:28 +0000 | [diff] [blame] | 151 | pass |
| 152 | else: |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 153 | if bs > 1: |
| 154 | buffering = bs |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 155 | if buffering < 0: |
| 156 | raise ValueError("invalid buffering size") |
| 157 | if buffering == 0: |
| 158 | if binary: |
Guido van Rossum | 13633bb | 2007-04-13 18:42:35 +0000 | [diff] [blame] | 159 | raw._name = file |
| 160 | raw._mode = mode |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 161 | return raw |
| 162 | raise ValueError("can't have unbuffered text I/O") |
| 163 | if updating: |
| 164 | buffer = BufferedRandom(raw, buffering) |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 165 | elif writing or appending: |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 166 | buffer = BufferedWriter(raw, buffering) |
Guido van Rossum | 5abbf75 | 2007-08-27 17:39:33 +0000 | [diff] [blame] | 167 | elif reading: |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 168 | buffer = BufferedReader(raw, buffering) |
Guido van Rossum | 5abbf75 | 2007-08-27 17:39:33 +0000 | [diff] [blame] | 169 | else: |
| 170 | raise ValueError("unknown mode: %r" % mode) |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 171 | if binary: |
Guido van Rossum | 13633bb | 2007-04-13 18:42:35 +0000 | [diff] [blame] | 172 | buffer.name = file |
| 173 | buffer.mode = mode |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 174 | return buffer |
Guido van Rossum | 13633bb | 2007-04-13 18:42:35 +0000 | [diff] [blame] | 175 | text = TextIOWrapper(buffer, encoding, newline) |
| 176 | text.name = file |
| 177 | text.mode = mode |
| 178 | return text |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 179 | |
| 180 | |
Guido van Rossum | ce3a72a | 2007-10-19 23:16:50 +0000 | [diff] [blame] | 181 | class OpenWrapper: |
| 182 | """Wrapper for __builtin__.open |
| 183 | |
| 184 | Trick so that open won't become a bound method when stored |
| 185 | as a class variable (as dumbdbm does). |
| 186 | |
| 187 | See initstdio() in Python/pythonrun.c. |
| 188 | """ |
| 189 | def __new__(cls, *args, **kwargs): |
| 190 | return open(*args, **kwargs) |
| 191 | |
| 192 | |
Guido van Rossum | 4b5386f | 2007-07-10 09:12:49 +0000 | [diff] [blame] | 193 | class UnsupportedOperation(ValueError, IOError): |
| 194 | pass |
| 195 | |
| 196 | |
Guido van Rossum | b7f136e | 2007-08-22 18:14:10 +0000 | [diff] [blame] | 197 | class IOBase(metaclass=abc.ABCMeta): |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 198 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 199 | """Base class for all I/O classes. |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 200 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 201 | This class provides dummy implementations for many methods that |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 202 | derived classes can override selectively; the default |
| 203 | implementations represent a file that cannot be read, written or |
| 204 | seeked. |
| 205 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 206 | This does not define read(), readinto() and write(), nor |
| 207 | readline() and friends, since their signatures vary per layer. |
Guido van Rossum | 53807da | 2007-04-10 19:01:47 +0000 | [diff] [blame] | 208 | |
| 209 | Not that calling any method (even inquiries) on a closed file is |
| 210 | undefined. Implementations may raise IOError in this case. |
Guido van Rossum | 17e43e5 | 2007-02-27 15:45:13 +0000 | [diff] [blame] | 211 | """ |
| 212 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 213 | ### Internal ### |
| 214 | |
| 215 | def _unsupported(self, name: str) -> IOError: |
| 216 | """Internal: raise an exception for unsupported operations.""" |
Guido van Rossum | 4b5386f | 2007-07-10 09:12:49 +0000 | [diff] [blame] | 217 | raise UnsupportedOperation("%s.%s() not supported" % |
| 218 | (self.__class__.__name__, name)) |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 219 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 220 | ### Positioning ### |
| 221 | |
Guido van Rossum | 53807da | 2007-04-10 19:01:47 +0000 | [diff] [blame] | 222 | def seek(self, pos: int, whence: int = 0) -> int: |
| 223 | """seek(pos: int, whence: int = 0) -> int. Change stream position. |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 224 | |
| 225 | Seek to byte offset pos relative to position indicated by whence: |
| 226 | 0 Start of stream (the default). pos should be >= 0; |
| 227 | 1 Current position - whence may be negative; |
| 228 | 2 End of stream - whence usually negative. |
Guido van Rossum | 53807da | 2007-04-10 19:01:47 +0000 | [diff] [blame] | 229 | Returns the new absolute position. |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 230 | """ |
| 231 | self._unsupported("seek") |
| 232 | |
| 233 | def tell(self) -> int: |
| 234 | """tell() -> int. Return current stream position.""" |
Guido van Rossum | 53807da | 2007-04-10 19:01:47 +0000 | [diff] [blame] | 235 | return self.seek(0, 1) |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 236 | |
Guido van Rossum | 8742977 | 2007-04-10 21:06:59 +0000 | [diff] [blame] | 237 | def truncate(self, pos: int = None) -> int: |
| 238 | """truncate(size: int = None) -> int. Truncate file to size bytes. |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 239 | |
| 240 | Size defaults to the current IO position as reported by tell(). |
Guido van Rossum | 8742977 | 2007-04-10 21:06:59 +0000 | [diff] [blame] | 241 | Returns the new size. |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 242 | """ |
| 243 | self._unsupported("truncate") |
| 244 | |
| 245 | ### Flush and close ### |
| 246 | |
| 247 | def flush(self) -> None: |
| 248 | """flush() -> None. Flushes write buffers, if applicable. |
| 249 | |
| 250 | This is a no-op for read-only and non-blocking streams. |
| 251 | """ |
Guido van Rossum | d410395 | 2007-04-12 05:44:49 +0000 | [diff] [blame] | 252 | # XXX Should this return the number of bytes written??? |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 253 | |
| 254 | __closed = False |
| 255 | |
| 256 | def close(self) -> None: |
| 257 | """close() -> None. Flushes and closes the IO object. |
| 258 | |
| 259 | This must be idempotent. It should also set a flag for the |
| 260 | 'closed' property (see below) to test. |
| 261 | """ |
| 262 | if not self.__closed: |
Guido van Rossum | 469734b | 2007-07-10 12:00:45 +0000 | [diff] [blame] | 263 | try: |
| 264 | self.flush() |
Guido van Rossum | 33e7a8e | 2007-07-22 20:38:07 +0000 | [diff] [blame] | 265 | except IOError: |
| 266 | pass # If flush() fails, just give up |
| 267 | self.__closed = True |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 268 | |
| 269 | def __del__(self) -> None: |
| 270 | """Destructor. Calls close().""" |
| 271 | # The try/except block is in case this is called at program |
| 272 | # exit time, when it's possible that globals have already been |
| 273 | # deleted, and then the close() call might fail. Since |
| 274 | # there's nothing we can do about such failures and they annoy |
| 275 | # the end users, we suppress the traceback. |
| 276 | try: |
| 277 | self.close() |
| 278 | except: |
| 279 | pass |
| 280 | |
| 281 | ### Inquiries ### |
| 282 | |
| 283 | def seekable(self) -> bool: |
| 284 | """seekable() -> bool. Return whether object supports random access. |
| 285 | |
| 286 | If False, seek(), tell() and truncate() will raise IOError. |
| 287 | This method may need to do a test seek(). |
| 288 | """ |
| 289 | return False |
| 290 | |
Guido van Rossum | 5abbf75 | 2007-08-27 17:39:33 +0000 | [diff] [blame] | 291 | def _checkSeekable(self, msg=None): |
| 292 | """Internal: raise an IOError if file is not seekable |
| 293 | """ |
| 294 | if not self.seekable(): |
| 295 | raise IOError("File or stream is not seekable." |
| 296 | if msg is None else msg) |
| 297 | |
| 298 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 299 | def readable(self) -> bool: |
| 300 | """readable() -> bool. Return whether object was opened for reading. |
| 301 | |
| 302 | If False, read() will raise IOError. |
| 303 | """ |
| 304 | return False |
| 305 | |
Guido van Rossum | 5abbf75 | 2007-08-27 17:39:33 +0000 | [diff] [blame] | 306 | def _checkReadable(self, msg=None): |
| 307 | """Internal: raise an IOError if file is not readable |
| 308 | """ |
| 309 | if not self.readable(): |
| 310 | raise IOError("File or stream is not readable." |
| 311 | if msg is None else msg) |
| 312 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 313 | def writable(self) -> bool: |
| 314 | """writable() -> bool. Return whether object was opened for writing. |
| 315 | |
| 316 | If False, write() and truncate() will raise IOError. |
| 317 | """ |
| 318 | return False |
| 319 | |
Guido van Rossum | 5abbf75 | 2007-08-27 17:39:33 +0000 | [diff] [blame] | 320 | def _checkWritable(self, msg=None): |
| 321 | """Internal: raise an IOError if file is not writable |
| 322 | """ |
| 323 | if not self.writable(): |
| 324 | raise IOError("File or stream is not writable." |
| 325 | if msg is None else msg) |
| 326 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 327 | @property |
| 328 | def closed(self): |
| 329 | """closed: bool. True iff the file has been closed. |
| 330 | |
| 331 | For backwards compatibility, this is a property, not a predicate. |
| 332 | """ |
| 333 | return self.__closed |
| 334 | |
Guido van Rossum | 5abbf75 | 2007-08-27 17:39:33 +0000 | [diff] [blame] | 335 | def _checkClosed(self, msg=None): |
| 336 | """Internal: raise an ValueError if file is closed |
| 337 | """ |
| 338 | if self.closed: |
| 339 | raise ValueError("I/O operation on closed file." |
| 340 | if msg is None else msg) |
| 341 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 342 | ### Context manager ### |
| 343 | |
| 344 | def __enter__(self) -> "IOBase": # That's a forward reference |
| 345 | """Context management protocol. Returns self.""" |
| 346 | return self |
| 347 | |
| 348 | def __exit__(self, *args) -> None: |
| 349 | """Context management protocol. Calls close()""" |
| 350 | self.close() |
| 351 | |
| 352 | ### Lower-level APIs ### |
| 353 | |
| 354 | # XXX Should these be present even if unimplemented? |
| 355 | |
| 356 | def fileno(self) -> int: |
| 357 | """fileno() -> int. Returns underlying file descriptor if one exists. |
| 358 | |
| 359 | Raises IOError if the IO object does not use a file descriptor. |
| 360 | """ |
| 361 | self._unsupported("fileno") |
| 362 | |
| 363 | def isatty(self) -> bool: |
| 364 | """isatty() -> int. Returns whether this is an 'interactive' stream. |
| 365 | |
| 366 | Returns False if we don't know. |
| 367 | """ |
Guido van Rossum | 5abbf75 | 2007-08-27 17:39:33 +0000 | [diff] [blame] | 368 | self._checkClosed() |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 369 | return False |
| 370 | |
Guido van Rossum | 7165cb1 | 2007-07-10 06:54:34 +0000 | [diff] [blame] | 371 | ### Readline[s] and writelines ### |
Guido van Rossum | 7d0a826 | 2007-05-21 23:13:11 +0000 | [diff] [blame] | 372 | |
Guido van Rossum | 48fc58a | 2007-06-07 23:45:37 +0000 | [diff] [blame] | 373 | def readline(self, limit: int = -1) -> bytes: |
| 374 | """For backwards compatibility, a (slowish) readline().""" |
Guido van Rossum | 2bf7138 | 2007-06-08 00:07:57 +0000 | [diff] [blame] | 375 | if hasattr(self, "peek"): |
| 376 | def nreadahead(): |
| 377 | readahead = self.peek(1, unsafe=True) |
| 378 | if not readahead: |
| 379 | return 1 |
| 380 | n = (readahead.find(b"\n") + 1) or len(readahead) |
| 381 | if limit >= 0: |
| 382 | n = min(n, limit) |
| 383 | return n |
| 384 | else: |
| 385 | def nreadahead(): |
| 386 | return 1 |
Guido van Rossum | 48fc58a | 2007-06-07 23:45:37 +0000 | [diff] [blame] | 387 | if limit is None: |
| 388 | limit = -1 |
| 389 | res = bytes() |
| 390 | while limit < 0 or len(res) < limit: |
Guido van Rossum | 2bf7138 | 2007-06-08 00:07:57 +0000 | [diff] [blame] | 391 | b = self.read(nreadahead()) |
Guido van Rossum | 7d0a826 | 2007-05-21 23:13:11 +0000 | [diff] [blame] | 392 | if not b: |
| 393 | break |
| 394 | res += b |
Guido van Rossum | 48fc58a | 2007-06-07 23:45:37 +0000 | [diff] [blame] | 395 | if res.endswith(b"\n"): |
Guido van Rossum | 7d0a826 | 2007-05-21 23:13:11 +0000 | [diff] [blame] | 396 | break |
| 397 | return res |
| 398 | |
Guido van Rossum | 7165cb1 | 2007-07-10 06:54:34 +0000 | [diff] [blame] | 399 | def __iter__(self): |
Guido van Rossum | 5abbf75 | 2007-08-27 17:39:33 +0000 | [diff] [blame] | 400 | self._checkClosed() |
Guido van Rossum | 7165cb1 | 2007-07-10 06:54:34 +0000 | [diff] [blame] | 401 | return self |
| 402 | |
| 403 | def __next__(self): |
| 404 | line = self.readline() |
| 405 | if not line: |
| 406 | raise StopIteration |
| 407 | return line |
| 408 | |
| 409 | def readlines(self, hint=None): |
| 410 | if hint is None: |
| 411 | return list(self) |
| 412 | n = 0 |
| 413 | lines = [] |
| 414 | for line in self: |
| 415 | lines.append(line) |
| 416 | n += len(line) |
| 417 | if n >= hint: |
| 418 | break |
| 419 | return lines |
| 420 | |
| 421 | def writelines(self, lines): |
Guido van Rossum | 5abbf75 | 2007-08-27 17:39:33 +0000 | [diff] [blame] | 422 | self._checkClosed() |
Guido van Rossum | 7165cb1 | 2007-07-10 06:54:34 +0000 | [diff] [blame] | 423 | for line in lines: |
| 424 | self.write(line) |
| 425 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 426 | |
| 427 | class RawIOBase(IOBase): |
| 428 | |
| 429 | """Base class for raw binary I/O. |
| 430 | |
| 431 | The read() method is implemented by calling readinto(); derived |
| 432 | classes that want to support read() only need to implement |
| 433 | readinto() as a primitive operation. In general, readinto() |
| 434 | can be more efficient than read(). |
| 435 | |
| 436 | (It would be tempting to also provide an implementation of |
| 437 | readinto() in terms of read(), in case the latter is a more |
| 438 | suitable primitive operation, but that would lead to nasty |
| 439 | recursion in case a subclass doesn't implement either.) |
| 440 | """ |
| 441 | |
Guido van Rossum | 7165cb1 | 2007-07-10 06:54:34 +0000 | [diff] [blame] | 442 | def read(self, n: int = -1) -> bytes: |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 443 | """read(n: int) -> bytes. Read and return up to n bytes. |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 444 | |
| 445 | Returns an empty bytes array on EOF, or None if the object is |
| 446 | set not to block and has no data to read. |
| 447 | """ |
Guido van Rossum | 7165cb1 | 2007-07-10 06:54:34 +0000 | [diff] [blame] | 448 | if n is None: |
| 449 | n = -1 |
| 450 | if n < 0: |
| 451 | return self.readall() |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 452 | b = bytes(n.__index__()) |
Guido van Rossum | 00efead | 2007-03-07 05:23:25 +0000 | [diff] [blame] | 453 | n = self.readinto(b) |
| 454 | del b[n:] |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 455 | return b |
| 456 | |
Guido van Rossum | 7165cb1 | 2007-07-10 06:54:34 +0000 | [diff] [blame] | 457 | def readall(self): |
| 458 | """readall() -> bytes. Read until EOF, using multiple read() call.""" |
| 459 | res = bytes() |
| 460 | while True: |
| 461 | data = self.read(DEFAULT_BUFFER_SIZE) |
| 462 | if not data: |
| 463 | break |
| 464 | res += data |
| 465 | return res |
| 466 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 467 | def readinto(self, b: bytes) -> int: |
| 468 | """readinto(b: bytes) -> int. Read up to len(b) bytes into b. |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 469 | |
| 470 | Returns number of bytes read (0 for EOF), or None if the object |
| 471 | is set not to block as has no data to read. |
| 472 | """ |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 473 | self._unsupported("readinto") |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 474 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 475 | def write(self, b: bytes) -> int: |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 476 | """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] | 477 | |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 478 | 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] | 479 | """ |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 480 | self._unsupported("write") |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 481 | |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 482 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 483 | class FileIO(_fileio._FileIO, RawIOBase): |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 484 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 485 | """Raw I/O implementation for OS files. |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 486 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 487 | This multiply inherits from _FileIO and RawIOBase to make |
| 488 | isinstance(io.FileIO(), io.RawIOBase) return True without |
| 489 | requiring that _fileio._FileIO inherits from io.RawIOBase (which |
| 490 | would be hard to do since _fileio.c is written in C). |
| 491 | """ |
Guido van Rossum | a9e2024 | 2007-03-08 00:43:48 +0000 | [diff] [blame] | 492 | |
Guido van Rossum | 8742977 | 2007-04-10 21:06:59 +0000 | [diff] [blame] | 493 | def close(self): |
| 494 | _fileio._FileIO.close(self) |
| 495 | RawIOBase.close(self) |
| 496 | |
Guido van Rossum | 13633bb | 2007-04-13 18:42:35 +0000 | [diff] [blame] | 497 | @property |
| 498 | def name(self): |
| 499 | return self._name |
| 500 | |
| 501 | @property |
| 502 | def mode(self): |
| 503 | return self._mode |
| 504 | |
Guido van Rossum | a9e2024 | 2007-03-08 00:43:48 +0000 | [diff] [blame] | 505 | |
Guido van Rossum | cce92b2 | 2007-04-10 14:41:39 +0000 | [diff] [blame] | 506 | class BufferedIOBase(IOBase): |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 507 | |
| 508 | """Base class for buffered IO objects. |
| 509 | |
| 510 | The main difference with RawIOBase is that the read() method |
| 511 | supports omitting the size argument, and does not have a default |
| 512 | implementation that defers to readinto(). |
| 513 | |
| 514 | In addition, read(), readinto() and write() may raise |
| 515 | BlockingIOError if the underlying raw stream is in non-blocking |
| 516 | mode and not ready; unlike their raw counterparts, they will never |
| 517 | return None. |
| 518 | |
| 519 | A typical implementation should not inherit from a RawIOBase |
| 520 | implementation, but wrap one. |
| 521 | """ |
| 522 | |
Guido van Rossum | c2f93dc | 2007-05-24 00:50:02 +0000 | [diff] [blame] | 523 | def read(self, n: int = None) -> bytes: |
| 524 | """read(n: int = None) -> bytes. Read and return up to n bytes. |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 525 | |
Guido van Rossum | 024da5c | 2007-05-17 23:59:11 +0000 | [diff] [blame] | 526 | If the argument is omitted, None, or negative, reads and |
| 527 | returns all data until EOF. |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 528 | |
| 529 | If the argument is positive, and the underlying raw stream is |
| 530 | not 'interactive', multiple raw reads may be issued to satisfy |
| 531 | the byte count (unless EOF is reached first). But for |
| 532 | interactive raw streams (XXX and for pipes?), at most one raw |
| 533 | read will be issued, and a short result does not imply that |
| 534 | EOF is imminent. |
| 535 | |
| 536 | Returns an empty bytes array on EOF. |
| 537 | |
| 538 | Raises BlockingIOError if the underlying raw stream has no |
| 539 | data at the moment. |
| 540 | """ |
| 541 | self._unsupported("read") |
| 542 | |
| 543 | def readinto(self, b: bytes) -> int: |
| 544 | """readinto(b: bytes) -> int. Read up to len(b) bytes into b. |
| 545 | |
| 546 | Like read(), this may issue multiple reads to the underlying |
| 547 | raw stream, unless the latter is 'interactive' (XXX or a |
| 548 | pipe?). |
| 549 | |
| 550 | Returns the number of bytes read (0 for EOF). |
| 551 | |
| 552 | Raises BlockingIOError if the underlying raw stream has no |
| 553 | data at the moment. |
| 554 | """ |
Guido van Rossum | d410395 | 2007-04-12 05:44:49 +0000 | [diff] [blame] | 555 | # XXX This ought to work with anything that supports the buffer API |
Guido van Rossum | 8742977 | 2007-04-10 21:06:59 +0000 | [diff] [blame] | 556 | data = self.read(len(b)) |
| 557 | n = len(data) |
Guido van Rossum | 7165cb1 | 2007-07-10 06:54:34 +0000 | [diff] [blame] | 558 | try: |
| 559 | b[:n] = data |
| 560 | except TypeError as err: |
| 561 | import array |
| 562 | if not isinstance(b, array.array): |
| 563 | raise err |
| 564 | b[:n] = array.array('b', data) |
Guido van Rossum | 8742977 | 2007-04-10 21:06:59 +0000 | [diff] [blame] | 565 | return n |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 566 | |
| 567 | def write(self, b: bytes) -> int: |
| 568 | """write(b: bytes) -> int. Write the given buffer to the IO stream. |
| 569 | |
| 570 | Returns the number of bytes written, which is never less than |
| 571 | len(b). |
| 572 | |
| 573 | Raises BlockingIOError if the buffer is full and the |
| 574 | underlying raw stream cannot accept more data at the moment. |
| 575 | """ |
| 576 | self._unsupported("write") |
| 577 | |
| 578 | |
| 579 | class _BufferedIOMixin(BufferedIOBase): |
| 580 | |
| 581 | """A mixin implementation of BufferedIOBase with an underlying raw stream. |
| 582 | |
| 583 | This passes most requests on to the underlying raw stream. It |
| 584 | does *not* provide implementations of read(), readinto() or |
| 585 | write(). |
| 586 | """ |
| 587 | |
| 588 | def __init__(self, raw): |
| 589 | self.raw = raw |
| 590 | |
| 591 | ### Positioning ### |
| 592 | |
| 593 | def seek(self, pos, whence=0): |
Guido van Rossum | 53807da | 2007-04-10 19:01:47 +0000 | [diff] [blame] | 594 | return self.raw.seek(pos, whence) |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 595 | |
| 596 | def tell(self): |
| 597 | return self.raw.tell() |
| 598 | |
| 599 | def truncate(self, pos=None): |
Guido van Rossum | 79b79ee | 2007-10-25 23:21:03 +0000 | [diff] [blame^] | 600 | # On Windows, the truncate operation changes the current position |
| 601 | # to the end of the file, which may leave us with desynchronized |
| 602 | # buffers. |
| 603 | # Since we promise that truncate() won't change the current position, |
| 604 | # the easiest thing is to capture current pos now and seek back to |
| 605 | # it at the end. |
| 606 | |
| 607 | initialpos = self.tell() |
Guido van Rossum | 7165cb1 | 2007-07-10 06:54:34 +0000 | [diff] [blame] | 608 | if pos is None: |
Guido van Rossum | 79b79ee | 2007-10-25 23:21:03 +0000 | [diff] [blame^] | 609 | pos = initialpos |
| 610 | |
| 611 | # Flush the stream. We're mixing buffered I/O with lower-level I/O, |
| 612 | # and a flush may be necessary to synch both views of the current |
| 613 | # file state. |
| 614 | self.flush() |
| 615 | newpos = self.raw.truncate(pos) |
| 616 | self.seek(initialpos) |
| 617 | return newpos |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 618 | |
| 619 | ### Flush and close ### |
| 620 | |
| 621 | def flush(self): |
| 622 | self.raw.flush() |
| 623 | |
| 624 | def close(self): |
Guido van Rossum | 4b5386f | 2007-07-10 09:12:49 +0000 | [diff] [blame] | 625 | if not self.closed: |
Guido van Rossum | 33e7a8e | 2007-07-22 20:38:07 +0000 | [diff] [blame] | 626 | try: |
| 627 | self.flush() |
| 628 | except IOError: |
| 629 | pass # If flush() fails, just give up |
Guido van Rossum | 4b5386f | 2007-07-10 09:12:49 +0000 | [diff] [blame] | 630 | self.raw.close() |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 631 | |
| 632 | ### Inquiries ### |
| 633 | |
| 634 | def seekable(self): |
| 635 | return self.raw.seekable() |
| 636 | |
| 637 | def readable(self): |
| 638 | return self.raw.readable() |
| 639 | |
| 640 | def writable(self): |
| 641 | return self.raw.writable() |
| 642 | |
| 643 | @property |
| 644 | def closed(self): |
| 645 | return self.raw.closed |
| 646 | |
| 647 | ### Lower-level APIs ### |
| 648 | |
| 649 | def fileno(self): |
| 650 | return self.raw.fileno() |
| 651 | |
| 652 | def isatty(self): |
| 653 | return self.raw.isatty() |
| 654 | |
| 655 | |
Guido van Rossum | 024da5c | 2007-05-17 23:59:11 +0000 | [diff] [blame] | 656 | class BytesIO(BufferedIOBase): |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 657 | |
Guido van Rossum | 024da5c | 2007-05-17 23:59:11 +0000 | [diff] [blame] | 658 | """Buffered I/O implementation using an in-memory bytes buffer.""" |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 659 | |
Guido van Rossum | 024da5c | 2007-05-17 23:59:11 +0000 | [diff] [blame] | 660 | # XXX More docs |
| 661 | |
| 662 | def __init__(self, initial_bytes=None): |
| 663 | buffer = b"" |
| 664 | if initial_bytes is not None: |
| 665 | buffer += initial_bytes |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 666 | self._buffer = buffer |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 667 | self._pos = 0 |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 668 | |
| 669 | def getvalue(self): |
| 670 | return self._buffer |
| 671 | |
Guido van Rossum | 024da5c | 2007-05-17 23:59:11 +0000 | [diff] [blame] | 672 | def read(self, n=None): |
| 673 | if n is None: |
| 674 | n = -1 |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 675 | if n < 0: |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 676 | n = len(self._buffer) |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 677 | newpos = min(len(self._buffer), self._pos + n) |
| 678 | b = self._buffer[self._pos : newpos] |
| 679 | self._pos = newpos |
| 680 | return b |
| 681 | |
Guido van Rossum | 024da5c | 2007-05-17 23:59:11 +0000 | [diff] [blame] | 682 | def read1(self, n): |
| 683 | return self.read(n) |
| 684 | |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 685 | def write(self, b): |
Guido van Rossum | 4b5386f | 2007-07-10 09:12:49 +0000 | [diff] [blame] | 686 | if self.closed: |
| 687 | raise ValueError("write to closed file") |
Guido van Rossum | a74184e | 2007-08-29 04:05:57 +0000 | [diff] [blame] | 688 | if isinstance(b, str): |
| 689 | raise TypeError("can't write str to binary stream") |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 690 | n = len(b) |
| 691 | newpos = self._pos + n |
Guido van Rossum | b972a78 | 2007-07-21 00:25:15 +0000 | [diff] [blame] | 692 | if newpos > len(self._buffer): |
| 693 | # Inserts null bytes between the current end of the file |
| 694 | # and the new write position. |
Guido van Rossum | a74184e | 2007-08-29 04:05:57 +0000 | [diff] [blame] | 695 | padding = b'\x00' * (newpos - len(self._buffer) - n) |
Guido van Rossum | b972a78 | 2007-07-21 00:25:15 +0000 | [diff] [blame] | 696 | self._buffer[self._pos:newpos - n] = padding |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 697 | self._buffer[self._pos:newpos] = b |
| 698 | self._pos = newpos |
| 699 | return n |
| 700 | |
| 701 | def seek(self, pos, whence=0): |
| 702 | if whence == 0: |
| 703 | self._pos = max(0, pos) |
| 704 | elif whence == 1: |
| 705 | self._pos = max(0, self._pos + pos) |
| 706 | elif whence == 2: |
| 707 | self._pos = max(0, len(self._buffer) + pos) |
| 708 | else: |
| 709 | raise IOError("invalid whence value") |
Guido van Rossum | 53807da | 2007-04-10 19:01:47 +0000 | [diff] [blame] | 710 | return self._pos |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 711 | |
| 712 | def tell(self): |
| 713 | return self._pos |
| 714 | |
| 715 | def truncate(self, pos=None): |
| 716 | if pos is None: |
| 717 | pos = self._pos |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 718 | del self._buffer[pos:] |
Guido van Rossum | 8742977 | 2007-04-10 21:06:59 +0000 | [diff] [blame] | 719 | return pos |
Guido van Rossum | 28524c7 | 2007-02-27 05:47:44 +0000 | [diff] [blame] | 720 | |
| 721 | def readable(self): |
| 722 | return True |
| 723 | |
| 724 | def writable(self): |
| 725 | return True |
| 726 | |
| 727 | def seekable(self): |
| 728 | return True |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 729 | |
| 730 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 731 | class BufferedReader(_BufferedIOMixin): |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 732 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 733 | """Buffer for a readable sequential RawIO object.""" |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 734 | |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 735 | def __init__(self, raw, buffer_size=DEFAULT_BUFFER_SIZE): |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 736 | """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] | 737 | """ |
Guido van Rossum | 5abbf75 | 2007-08-27 17:39:33 +0000 | [diff] [blame] | 738 | raw._checkReadable() |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 739 | _BufferedIOMixin.__init__(self, raw) |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 740 | self._read_buf = b"" |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 741 | self.buffer_size = buffer_size |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 742 | |
Guido van Rossum | 024da5c | 2007-05-17 23:59:11 +0000 | [diff] [blame] | 743 | def read(self, n=None): |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 744 | """Read n bytes. |
| 745 | |
| 746 | Returns exactly n bytes of data unless the underlying raw IO |
Walter Dörwald | a327000 | 2007-05-29 19:13:29 +0000 | [diff] [blame] | 747 | stream reaches EOF or if the call would block in non-blocking |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 748 | mode. If n is negative, read until EOF or until read() would |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 749 | block. |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 750 | """ |
Guido van Rossum | 024da5c | 2007-05-17 23:59:11 +0000 | [diff] [blame] | 751 | if n is None: |
| 752 | n = -1 |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 753 | nodata_val = b"" |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 754 | while n < 0 or len(self._read_buf) < n: |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 755 | to_read = max(self.buffer_size, |
| 756 | 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] | 757 | current = self.raw.read(to_read) |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 758 | if current in (b"", None): |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 759 | nodata_val = current |
| 760 | break |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 761 | self._read_buf += current |
| 762 | if self._read_buf: |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 763 | if n < 0: |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 764 | n = len(self._read_buf) |
| 765 | out = self._read_buf[:n] |
| 766 | self._read_buf = self._read_buf[n:] |
| 767 | else: |
| 768 | out = nodata_val |
| 769 | return out |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 770 | |
Guido van Rossum | 13633bb | 2007-04-13 18:42:35 +0000 | [diff] [blame] | 771 | def peek(self, n=0, *, unsafe=False): |
| 772 | """Returns buffered bytes without advancing the position. |
| 773 | |
| 774 | The argument indicates a desired minimal number of bytes; we |
| 775 | do at most one raw read to satisfy it. We never return more |
| 776 | than self.buffer_size. |
| 777 | |
| 778 | Unless unsafe=True is passed, we return a copy. |
| 779 | """ |
| 780 | want = min(n, self.buffer_size) |
| 781 | have = len(self._read_buf) |
| 782 | if have < want: |
| 783 | to_read = self.buffer_size - have |
| 784 | current = self.raw.read(to_read) |
| 785 | if current: |
| 786 | self._read_buf += current |
| 787 | result = self._read_buf |
| 788 | if unsafe: |
| 789 | result = result[:] |
| 790 | return result |
| 791 | |
| 792 | def read1(self, n): |
| 793 | """Reads up to n bytes. |
| 794 | |
| 795 | Returns up to n bytes. If at least one byte is buffered, |
| 796 | we only return buffered bytes. Otherwise, we do one |
| 797 | raw read. |
| 798 | """ |
| 799 | if n <= 0: |
| 800 | return b"" |
| 801 | self.peek(1, unsafe=True) |
| 802 | return self.read(min(n, len(self._read_buf))) |
| 803 | |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 804 | def tell(self): |
| 805 | return self.raw.tell() - len(self._read_buf) |
| 806 | |
| 807 | def seek(self, pos, whence=0): |
| 808 | if whence == 1: |
| 809 | pos -= len(self._read_buf) |
Guido van Rossum | 53807da | 2007-04-10 19:01:47 +0000 | [diff] [blame] | 810 | pos = self.raw.seek(pos, whence) |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 811 | self._read_buf = b"" |
Guido van Rossum | 53807da | 2007-04-10 19:01:47 +0000 | [diff] [blame] | 812 | return pos |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 813 | |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 814 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 815 | class BufferedWriter(_BufferedIOMixin): |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 816 | |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 817 | # XXX docstring |
| 818 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 819 | def __init__(self, raw, |
| 820 | buffer_size=DEFAULT_BUFFER_SIZE, max_buffer_size=None): |
Guido van Rossum | 5abbf75 | 2007-08-27 17:39:33 +0000 | [diff] [blame] | 821 | raw._checkWritable() |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 822 | _BufferedIOMixin.__init__(self, raw) |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 823 | self.buffer_size = buffer_size |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 824 | self.max_buffer_size = (2*buffer_size |
| 825 | if max_buffer_size is None |
| 826 | else max_buffer_size) |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 827 | self._write_buf = b"" |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 828 | |
| 829 | def write(self, b): |
Guido van Rossum | 4b5386f | 2007-07-10 09:12:49 +0000 | [diff] [blame] | 830 | if self.closed: |
| 831 | raise ValueError("write to closed file") |
Guido van Rossum | a74184e | 2007-08-29 04:05:57 +0000 | [diff] [blame] | 832 | if isinstance(b, str): |
| 833 | raise TypeError("can't write str to binary stream") |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 834 | # XXX we can implement some more tricks to try and avoid partial writes |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 835 | if len(self._write_buf) > self.buffer_size: |
| 836 | # We're full, so let's pre-flush the buffer |
| 837 | try: |
| 838 | self.flush() |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 839 | except BlockingIOError as e: |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 840 | # We can't accept anything else. |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 841 | # XXX Why not just let the exception pass through? |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 842 | raise BlockingIOError(e.errno, e.strerror, 0) |
Guido van Rossum | d410395 | 2007-04-12 05:44:49 +0000 | [diff] [blame] | 843 | before = len(self._write_buf) |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 844 | self._write_buf.extend(b) |
Guido van Rossum | d410395 | 2007-04-12 05:44:49 +0000 | [diff] [blame] | 845 | written = len(self._write_buf) - before |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 846 | if len(self._write_buf) > self.buffer_size: |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 847 | try: |
| 848 | self.flush() |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 849 | except BlockingIOError as e: |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 850 | if (len(self._write_buf) > self.max_buffer_size): |
| 851 | # We've hit max_buffer_size. We have to accept a partial |
| 852 | # write and cut back our buffer. |
| 853 | overage = len(self._write_buf) - self.max_buffer_size |
| 854 | self._write_buf = self._write_buf[:self.max_buffer_size] |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 855 | raise BlockingIOError(e.errno, e.strerror, overage) |
Guido van Rossum | d410395 | 2007-04-12 05:44:49 +0000 | [diff] [blame] | 856 | return written |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 857 | |
| 858 | def flush(self): |
Guido van Rossum | 4b5386f | 2007-07-10 09:12:49 +0000 | [diff] [blame] | 859 | if self.closed: |
| 860 | raise ValueError("flush of closed file") |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 861 | written = 0 |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 862 | try: |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 863 | while self._write_buf: |
| 864 | n = self.raw.write(self._write_buf) |
| 865 | del self._write_buf[:n] |
| 866 | written += n |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 867 | except BlockingIOError as e: |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 868 | n = e.characters_written |
| 869 | del self._write_buf[:n] |
| 870 | written += n |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 871 | raise BlockingIOError(e.errno, e.strerror, written) |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 872 | |
| 873 | def tell(self): |
| 874 | return self.raw.tell() + len(self._write_buf) |
| 875 | |
| 876 | def seek(self, pos, whence=0): |
| 877 | self.flush() |
Guido van Rossum | 53807da | 2007-04-10 19:01:47 +0000 | [diff] [blame] | 878 | return self.raw.seek(pos, whence) |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 879 | |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 880 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 881 | class BufferedRWPair(BufferedIOBase): |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 882 | |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 883 | """A buffered reader and writer object together. |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 884 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 885 | A buffered reader object and buffered writer object put together |
| 886 | to form a sequential IO object that can read and write. |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 887 | |
| 888 | This is typically used with a socket or two-way pipe. |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 889 | |
| 890 | XXX The usefulness of this (compared to having two separate IO |
| 891 | objects) is questionable. |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 892 | """ |
| 893 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 894 | def __init__(self, reader, writer, |
| 895 | buffer_size=DEFAULT_BUFFER_SIZE, max_buffer_size=None): |
| 896 | """Constructor. |
| 897 | |
| 898 | The arguments are two RawIO instances. |
| 899 | """ |
Guido van Rossum | 5abbf75 | 2007-08-27 17:39:33 +0000 | [diff] [blame] | 900 | reader._checkReadable() |
| 901 | writer._checkWritable() |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 902 | self.reader = BufferedReader(reader, buffer_size) |
| 903 | self.writer = BufferedWriter(writer, buffer_size, max_buffer_size) |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 904 | |
Guido van Rossum | 024da5c | 2007-05-17 23:59:11 +0000 | [diff] [blame] | 905 | def read(self, n=None): |
| 906 | if n is None: |
| 907 | n = -1 |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 908 | return self.reader.read(n) |
| 909 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 910 | def readinto(self, b): |
| 911 | return self.reader.readinto(b) |
| 912 | |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 913 | def write(self, b): |
| 914 | return self.writer.write(b) |
| 915 | |
Guido van Rossum | 13633bb | 2007-04-13 18:42:35 +0000 | [diff] [blame] | 916 | def peek(self, n=0, *, unsafe=False): |
| 917 | return self.reader.peek(n, unsafe=unsafe) |
| 918 | |
| 919 | def read1(self, n): |
| 920 | return self.reader.read1(n) |
| 921 | |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 922 | def readable(self): |
| 923 | return self.reader.readable() |
| 924 | |
| 925 | def writable(self): |
| 926 | return self.writer.writable() |
| 927 | |
| 928 | def flush(self): |
| 929 | return self.writer.flush() |
Guido van Rossum | 68bbcd2 | 2007-02-27 17:19:33 +0000 | [diff] [blame] | 930 | |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 931 | def close(self): |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 932 | self.writer.close() |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 933 | self.reader.close() |
| 934 | |
| 935 | def isatty(self): |
| 936 | return self.reader.isatty() or self.writer.isatty() |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 937 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 938 | @property |
| 939 | def closed(self): |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 940 | return self.writer.closed() |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 941 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 942 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 943 | class BufferedRandom(BufferedWriter, BufferedReader): |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 944 | |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 945 | # XXX docstring |
| 946 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 947 | def __init__(self, raw, |
| 948 | buffer_size=DEFAULT_BUFFER_SIZE, max_buffer_size=None): |
Guido van Rossum | 5abbf75 | 2007-08-27 17:39:33 +0000 | [diff] [blame] | 949 | raw._checkSeekable() |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 950 | BufferedReader.__init__(self, raw, buffer_size) |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 951 | BufferedWriter.__init__(self, raw, buffer_size, max_buffer_size) |
| 952 | |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 953 | def seek(self, pos, whence=0): |
| 954 | self.flush() |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 955 | # First do the raw seek, then empty the read buffer, so that |
| 956 | # if the raw seek fails, we don't lose buffered data forever. |
Guido van Rossum | 53807da | 2007-04-10 19:01:47 +0000 | [diff] [blame] | 957 | pos = self.raw.seek(pos, whence) |
Guido van Rossum | 76c5d4d | 2007-04-06 19:10:29 +0000 | [diff] [blame] | 958 | self._read_buf = b"" |
Guido van Rossum | 53807da | 2007-04-10 19:01:47 +0000 | [diff] [blame] | 959 | return pos |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 960 | |
| 961 | def tell(self): |
| 962 | if (self._write_buf): |
| 963 | return self.raw.tell() + len(self._write_buf) |
| 964 | else: |
| 965 | return self.raw.tell() - len(self._read_buf) |
| 966 | |
Guido van Rossum | 024da5c | 2007-05-17 23:59:11 +0000 | [diff] [blame] | 967 | def read(self, n=None): |
| 968 | if n is None: |
| 969 | n = -1 |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 970 | self.flush() |
| 971 | return BufferedReader.read(self, n) |
| 972 | |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 973 | def readinto(self, b): |
| 974 | self.flush() |
| 975 | return BufferedReader.readinto(self, b) |
| 976 | |
Guido van Rossum | 13633bb | 2007-04-13 18:42:35 +0000 | [diff] [blame] | 977 | def peek(self, n=0, *, unsafe=False): |
| 978 | self.flush() |
| 979 | return BufferedReader.peek(self, n, unsafe=unsafe) |
| 980 | |
| 981 | def read1(self, n): |
| 982 | self.flush() |
| 983 | return BufferedReader.read1(self, n) |
| 984 | |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 985 | def write(self, b): |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 986 | if self._read_buf: |
| 987 | self.raw.seek(-len(self._read_buf), 1) # Undo readahead |
| 988 | self._read_buf = b"" |
Guido van Rossum | 01a2752 | 2007-03-07 01:00:12 +0000 | [diff] [blame] | 989 | return BufferedWriter.write(self, b) |
| 990 | |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 991 | |
Guido van Rossum | cce92b2 | 2007-04-10 14:41:39 +0000 | [diff] [blame] | 992 | class TextIOBase(IOBase): |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 993 | |
| 994 | """Base class for text I/O. |
| 995 | |
| 996 | This class provides a character and line based interface to stream I/O. |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 997 | |
| 998 | There is no readinto() method, as character strings are immutable. |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 999 | """ |
| 1000 | |
| 1001 | def read(self, n: int = -1) -> str: |
| 1002 | """read(n: int = -1) -> str. Read at most n characters from stream. |
| 1003 | |
| 1004 | Read from underlying buffer until we have n characters or we hit EOF. |
| 1005 | If n is negative or omitted, read until EOF. |
| 1006 | """ |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 1007 | self._unsupported("read") |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1008 | |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 1009 | def write(self, s: str) -> int: |
| 1010 | """write(s: str) -> int. Write string s to stream.""" |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 1011 | self._unsupported("write") |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1012 | |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 1013 | def truncate(self, pos: int = None) -> int: |
| 1014 | """truncate(pos: int = None) -> int. Truncate size to pos.""" |
| 1015 | self.flush() |
| 1016 | if pos is None: |
| 1017 | pos = self.tell() |
| 1018 | self.seek(pos) |
| 1019 | return self.buffer.truncate() |
| 1020 | |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1021 | def readline(self) -> str: |
| 1022 | """readline() -> str. Read until newline or EOF. |
| 1023 | |
| 1024 | Returns an empty string if EOF is hit immediately. |
| 1025 | """ |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 1026 | self._unsupported("readline") |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1027 | |
Guido van Rossum | fc3436b | 2007-05-24 17:58:06 +0000 | [diff] [blame] | 1028 | @property |
| 1029 | def encoding(self): |
| 1030 | """Subclasses should override.""" |
| 1031 | return None |
| 1032 | |
Guido van Rossum | 8358db2 | 2007-08-18 21:39:55 +0000 | [diff] [blame] | 1033 | @property |
| 1034 | def newlines(self): |
| 1035 | """newlines -> None | str | tuple of str. Line endings translated |
| 1036 | so far. |
| 1037 | |
| 1038 | Only line endings translated during reading are considered. |
| 1039 | |
| 1040 | Subclasses should override. |
| 1041 | """ |
| 1042 | return None |
| 1043 | |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1044 | |
| 1045 | class TextIOWrapper(TextIOBase): |
| 1046 | |
| 1047 | """Buffered text stream. |
| 1048 | |
| 1049 | Character and line based layer over a BufferedIOBase object. |
| 1050 | """ |
| 1051 | |
Guido van Rossum | b9c4c3e | 2007-04-11 16:07:50 +0000 | [diff] [blame] | 1052 | _CHUNK_SIZE = 128 |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1053 | |
| 1054 | def __init__(self, buffer, encoding=None, newline=None): |
Guido van Rossum | 8358db2 | 2007-08-18 21:39:55 +0000 | [diff] [blame] | 1055 | if newline not in (None, "", "\n", "\r", "\r\n"): |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 1056 | raise ValueError("illegal newline value: %r" % (newline,)) |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1057 | if encoding is None: |
Martin v. Löwis | d1cd4d4 | 2007-08-11 14:02:14 +0000 | [diff] [blame] | 1058 | try: |
| 1059 | encoding = os.device_encoding(buffer.fileno()) |
Brett Cannon | 041683d | 2007-10-11 23:08:53 +0000 | [diff] [blame] | 1060 | except (AttributeError, UnsupportedOperation): |
Martin v. Löwis | d1cd4d4 | 2007-08-11 14:02:14 +0000 | [diff] [blame] | 1061 | pass |
| 1062 | if encoding is None: |
Martin v. Löwis | d78d3b4 | 2007-08-11 15:36:45 +0000 | [diff] [blame] | 1063 | try: |
| 1064 | import locale |
| 1065 | except ImportError: |
| 1066 | # Importing locale may fail if Python is being built |
| 1067 | encoding = "ascii" |
| 1068 | else: |
| 1069 | encoding = locale.getpreferredencoding() |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1070 | |
| 1071 | self.buffer = buffer |
| 1072 | self._encoding = encoding |
Guido van Rossum | 8358db2 | 2007-08-18 21:39:55 +0000 | [diff] [blame] | 1073 | self._readuniversal = not newline |
| 1074 | self._readtranslate = newline is None |
| 1075 | self._readnl = newline |
| 1076 | self._writetranslate = newline != '' |
| 1077 | self._writenl = newline or os.linesep |
| 1078 | self._seennl = 0 |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1079 | self._decoder = None |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 1080 | self._pending = "" |
| 1081 | self._snapshot = None |
Guido van Rossum | b9c4c3e | 2007-04-11 16:07:50 +0000 | [diff] [blame] | 1082 | self._seekable = self._telling = self.buffer.seekable() |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 1083 | |
Guido van Rossum | fc3436b | 2007-05-24 17:58:06 +0000 | [diff] [blame] | 1084 | @property |
| 1085 | def encoding(self): |
| 1086 | return self._encoding |
| 1087 | |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 1088 | # A word about _snapshot. This attribute is either None, or a |
Guido van Rossum | d76e779 | 2007-04-17 02:38:04 +0000 | [diff] [blame] | 1089 | # tuple (decoder_state, readahead, pending) where decoder_state is |
| 1090 | # the second (integer) item of the decoder state, readahead is the |
| 1091 | # chunk of bytes that was read, and pending is the characters that |
| 1092 | # were rendered by the decoder after feeding it those bytes. We |
| 1093 | # use this to reconstruct intermediate decoder states in tell(). |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 1094 | |
| 1095 | def _seekable(self): |
| 1096 | return self._seekable |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1097 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 1098 | def flush(self): |
| 1099 | self.buffer.flush() |
Guido van Rossum | b9c4c3e | 2007-04-11 16:07:50 +0000 | [diff] [blame] | 1100 | self._telling = self._seekable |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 1101 | |
| 1102 | def close(self): |
Guido van Rossum | 33e7a8e | 2007-07-22 20:38:07 +0000 | [diff] [blame] | 1103 | try: |
| 1104 | self.flush() |
| 1105 | except: |
| 1106 | pass # If flush() fails, just give up |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 1107 | self.buffer.close() |
| 1108 | |
| 1109 | @property |
| 1110 | def closed(self): |
| 1111 | return self.buffer.closed |
| 1112 | |
Guido van Rossum | 9be5597 | 2007-04-07 02:59:27 +0000 | [diff] [blame] | 1113 | def fileno(self): |
| 1114 | return self.buffer.fileno() |
| 1115 | |
Guido van Rossum | 859b5ec | 2007-05-27 09:14:51 +0000 | [diff] [blame] | 1116 | def isatty(self): |
| 1117 | return self.buffer.isatty() |
| 1118 | |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1119 | def write(self, s: str): |
Guido van Rossum | 4b5386f | 2007-07-10 09:12:49 +0000 | [diff] [blame] | 1120 | if self.closed: |
| 1121 | raise ValueError("write to closed file") |
Guido van Rossum | 3172c5d | 2007-10-16 18:12:55 +0000 | [diff] [blame] | 1122 | if not isinstance(s, str): |
Guido van Rossum | dcce839 | 2007-08-29 18:10:08 +0000 | [diff] [blame] | 1123 | raise TypeError("can't write %s to text stream" % |
| 1124 | s.__class__.__name__) |
Guido van Rossum | 8358db2 | 2007-08-18 21:39:55 +0000 | [diff] [blame] | 1125 | haslf = "\n" in s |
| 1126 | if haslf and self._writetranslate and self._writenl != "\n": |
| 1127 | s = s.replace("\n", self._writenl) |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 1128 | # XXX What if we were just reading? |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 1129 | b = s.encode(self._encoding) |
Guido van Rossum | 8358db2 | 2007-08-18 21:39:55 +0000 | [diff] [blame] | 1130 | self.buffer.write(b) |
| 1131 | if haslf and self.isatty(): |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 1132 | self.flush() |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 1133 | self._snapshot = self._decoder = None |
| 1134 | return len(s) |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1135 | |
| 1136 | def _get_decoder(self): |
| 1137 | make_decoder = codecs.getincrementaldecoder(self._encoding) |
| 1138 | if make_decoder is None: |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 1139 | raise IOError("Can't find an incremental decoder for encoding %s" % |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1140 | self._encoding) |
| 1141 | decoder = self._decoder = make_decoder() # XXX: errors |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1142 | return decoder |
| 1143 | |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 1144 | def _read_chunk(self): |
Guido van Rossum | 5abbf75 | 2007-08-27 17:39:33 +0000 | [diff] [blame] | 1145 | if self._decoder is None: |
| 1146 | raise ValueError("no decoder") |
Guido van Rossum | b9c4c3e | 2007-04-11 16:07:50 +0000 | [diff] [blame] | 1147 | if not self._telling: |
Guido van Rossum | 13633bb | 2007-04-13 18:42:35 +0000 | [diff] [blame] | 1148 | readahead = self.buffer.read1(self._CHUNK_SIZE) |
Guido van Rossum | cba608c | 2007-04-11 14:19:59 +0000 | [diff] [blame] | 1149 | pending = self._decoder.decode(readahead, not readahead) |
| 1150 | return readahead, pending |
Guido van Rossum | d76e779 | 2007-04-17 02:38:04 +0000 | [diff] [blame] | 1151 | decoder_buffer, decoder_state = self._decoder.getstate() |
Guido van Rossum | 13633bb | 2007-04-13 18:42:35 +0000 | [diff] [blame] | 1152 | readahead = self.buffer.read1(self._CHUNK_SIZE) |
Guido van Rossum | cba608c | 2007-04-11 14:19:59 +0000 | [diff] [blame] | 1153 | pending = self._decoder.decode(readahead, not readahead) |
Guido van Rossum | d76e779 | 2007-04-17 02:38:04 +0000 | [diff] [blame] | 1154 | self._snapshot = (decoder_state, decoder_buffer + readahead, pending) |
Guido van Rossum | cba608c | 2007-04-11 14:19:59 +0000 | [diff] [blame] | 1155 | return readahead, pending |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 1156 | |
| 1157 | def _encode_decoder_state(self, ds, pos): |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 1158 | x = 0 |
| 1159 | for i in bytes(ds): |
| 1160 | x = x<<8 | i |
| 1161 | return (x<<64) | pos |
| 1162 | |
| 1163 | def _decode_decoder_state(self, pos): |
| 1164 | x, pos = divmod(pos, 1<<64) |
| 1165 | if not x: |
| 1166 | return None, pos |
| 1167 | b = b"" |
| 1168 | while x: |
| 1169 | b.append(x&0xff) |
| 1170 | x >>= 8 |
| 1171 | return str(b[::-1]), pos |
| 1172 | |
| 1173 | def tell(self): |
| 1174 | if not self._seekable: |
| 1175 | raise IOError("Underlying stream is not seekable") |
Guido van Rossum | b9c4c3e | 2007-04-11 16:07:50 +0000 | [diff] [blame] | 1176 | if not self._telling: |
| 1177 | raise IOError("Telling position disabled by next() call") |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 1178 | self.flush() |
Guido van Rossum | cba608c | 2007-04-11 14:19:59 +0000 | [diff] [blame] | 1179 | position = self.buffer.tell() |
Guido van Rossum | d76e779 | 2007-04-17 02:38:04 +0000 | [diff] [blame] | 1180 | decoder = self._decoder |
| 1181 | if decoder is None or self._snapshot is None: |
Guido van Rossum | 5abbf75 | 2007-08-27 17:39:33 +0000 | [diff] [blame] | 1182 | if self._pending: |
| 1183 | raise ValueError("pending data") |
Guido van Rossum | cba608c | 2007-04-11 14:19:59 +0000 | [diff] [blame] | 1184 | return position |
| 1185 | decoder_state, readahead, pending = self._snapshot |
| 1186 | position -= len(readahead) |
| 1187 | needed = len(pending) - len(self._pending) |
| 1188 | if not needed: |
| 1189 | return self._encode_decoder_state(decoder_state, position) |
Guido van Rossum | d76e779 | 2007-04-17 02:38:04 +0000 | [diff] [blame] | 1190 | saved_state = decoder.getstate() |
| 1191 | try: |
Guido van Rossum | 2b08b38 | 2007-05-08 20:18:39 +0000 | [diff] [blame] | 1192 | decoder.setstate((b"", decoder_state)) |
Guido van Rossum | d76e779 | 2007-04-17 02:38:04 +0000 | [diff] [blame] | 1193 | n = 0 |
| 1194 | bb = bytes(1) |
| 1195 | for i, bb[0] in enumerate(readahead): |
| 1196 | n += len(decoder.decode(bb)) |
| 1197 | if n >= needed: |
| 1198 | decoder_buffer, decoder_state = decoder.getstate() |
| 1199 | return self._encode_decoder_state( |
| 1200 | decoder_state, |
| 1201 | position + (i+1) - len(decoder_buffer)) |
| 1202 | raise IOError("Can't reconstruct logical file position") |
| 1203 | finally: |
| 1204 | decoder.setstate(saved_state) |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 1205 | |
| 1206 | def seek(self, pos, whence=0): |
| 1207 | if not self._seekable: |
| 1208 | raise IOError("Underlying stream is not seekable") |
| 1209 | if whence == 1: |
| 1210 | if pos != 0: |
| 1211 | raise IOError("Can't do nonzero cur-relative seeks") |
Guido van Rossum | aa43ed9 | 2007-04-12 05:24:24 +0000 | [diff] [blame] | 1212 | pos = self.tell() |
| 1213 | whence = 0 |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 1214 | if whence == 2: |
| 1215 | if pos != 0: |
| 1216 | raise IOError("Can't do nonzero end-relative seeks") |
| 1217 | self.flush() |
| 1218 | pos = self.buffer.seek(0, 2) |
| 1219 | self._snapshot = None |
| 1220 | self._pending = "" |
| 1221 | self._decoder = None |
| 1222 | return pos |
| 1223 | if whence != 0: |
| 1224 | raise ValueError("Invalid whence (%r, should be 0, 1 or 2)" % |
| 1225 | (whence,)) |
| 1226 | if pos < 0: |
| 1227 | raise ValueError("Negative seek position %r" % (pos,)) |
Guido van Rossum | b9c4c3e | 2007-04-11 16:07:50 +0000 | [diff] [blame] | 1228 | self.flush() |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 1229 | orig_pos = pos |
| 1230 | ds, pos = self._decode_decoder_state(pos) |
| 1231 | if not ds: |
| 1232 | self.buffer.seek(pos) |
| 1233 | self._snapshot = None |
| 1234 | self._pending = "" |
| 1235 | self._decoder = None |
| 1236 | return pos |
Guido van Rossum | d76e779 | 2007-04-17 02:38:04 +0000 | [diff] [blame] | 1237 | decoder = self._decoder or self._get_decoder() |
| 1238 | decoder.set_state(("", ds)) |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 1239 | self.buffer.seek(pos) |
Guido van Rossum | cba608c | 2007-04-11 14:19:59 +0000 | [diff] [blame] | 1240 | self._snapshot = (ds, b"", "") |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 1241 | self._pending = "" |
Guido van Rossum | cba608c | 2007-04-11 14:19:59 +0000 | [diff] [blame] | 1242 | self._decoder = decoder |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 1243 | return orig_pos |
| 1244 | |
Guido van Rossum | 024da5c | 2007-05-17 23:59:11 +0000 | [diff] [blame] | 1245 | def read(self, n=None): |
| 1246 | if n is None: |
| 1247 | n = -1 |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1248 | decoder = self._decoder or self._get_decoder() |
| 1249 | res = self._pending |
| 1250 | if n < 0: |
| 1251 | res += decoder.decode(self.buffer.read(), True) |
Guido van Rossum | 141f767 | 2007-04-10 00:22:16 +0000 | [diff] [blame] | 1252 | self._pending = "" |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 1253 | self._snapshot = None |
Guido van Rossum | 8358db2 | 2007-08-18 21:39:55 +0000 | [diff] [blame] | 1254 | return self._replacenl(res) |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1255 | else: |
| 1256 | while len(res) < n: |
Guido van Rossum | cba608c | 2007-04-11 14:19:59 +0000 | [diff] [blame] | 1257 | readahead, pending = self._read_chunk() |
| 1258 | res += pending |
| 1259 | if not readahead: |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1260 | break |
| 1261 | self._pending = res[n:] |
Guido van Rossum | 8358db2 | 2007-08-18 21:39:55 +0000 | [diff] [blame] | 1262 | return self._replacenl(res[:n]) |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1263 | |
Guido van Rossum | 024da5c | 2007-05-17 23:59:11 +0000 | [diff] [blame] | 1264 | def __next__(self): |
Guido van Rossum | b9c4c3e | 2007-04-11 16:07:50 +0000 | [diff] [blame] | 1265 | self._telling = False |
| 1266 | line = self.readline() |
| 1267 | if not line: |
| 1268 | self._snapshot = None |
| 1269 | self._telling = self._seekable |
| 1270 | raise StopIteration |
| 1271 | return line |
| 1272 | |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 1273 | def readline(self, limit=None): |
| 1274 | if limit is not None: |
Guido van Rossum | 9b76da6 | 2007-04-11 01:09:03 +0000 | [diff] [blame] | 1275 | # XXX Hack to support limit argument, for backwards compatibility |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 1276 | line = self.readline() |
| 1277 | if len(line) <= limit: |
Guido van Rossum | fa0054a | 2007-05-24 04:05:35 +0000 | [diff] [blame] | 1278 | return line |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 1279 | line, self._pending = line[:limit], line[limit:] + self._pending |
Guido van Rossum | fa0054a | 2007-05-24 04:05:35 +0000 | [diff] [blame] | 1280 | return line |
Guido van Rossum | 4f0db6e | 2007-04-08 23:59:06 +0000 | [diff] [blame] | 1281 | |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1282 | line = self._pending |
| 1283 | start = 0 |
Guido van Rossum | 8358db2 | 2007-08-18 21:39:55 +0000 | [diff] [blame] | 1284 | cr_eof = False |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1285 | decoder = self._decoder or self._get_decoder() |
| 1286 | |
Guido van Rossum | 8358db2 | 2007-08-18 21:39:55 +0000 | [diff] [blame] | 1287 | pos = endpos = None |
| 1288 | ending = None |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1289 | while True: |
Guido van Rossum | 8358db2 | 2007-08-18 21:39:55 +0000 | [diff] [blame] | 1290 | if self._readuniversal: |
| 1291 | # Universal newline search. Find any of \r, \r\n, \n |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1292 | |
Guido van Rossum | 8358db2 | 2007-08-18 21:39:55 +0000 | [diff] [blame] | 1293 | # In C we'd look for these in parallel of course. |
| 1294 | nlpos = line.find("\n", start) |
| 1295 | crpos = line.find("\r", start) |
| 1296 | if crpos == -1: |
| 1297 | if nlpos == -1: |
| 1298 | start = len(line) |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1299 | else: |
Guido van Rossum | 8358db2 | 2007-08-18 21:39:55 +0000 | [diff] [blame] | 1300 | # Found \n |
| 1301 | pos = nlpos |
| 1302 | endpos = pos + 1 |
| 1303 | ending = self._LF |
| 1304 | break |
| 1305 | elif nlpos == -1: |
| 1306 | if crpos == len(line) - 1: |
| 1307 | # Found \r at end of buffer, must keep reading |
| 1308 | start = crpos |
| 1309 | cr_eof = True |
| 1310 | else: |
| 1311 | # Found lone \r |
| 1312 | ending = self._CR |
| 1313 | pos = crpos |
| 1314 | endpos = pos + 1 |
| 1315 | break |
| 1316 | elif nlpos < crpos: |
| 1317 | # Found \n |
| 1318 | pos = nlpos |
| 1319 | endpos = pos + 1 |
| 1320 | ending = self._LF |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1321 | break |
Guido van Rossum | 8358db2 | 2007-08-18 21:39:55 +0000 | [diff] [blame] | 1322 | elif nlpos == crpos + 1: |
| 1323 | # Found \r\n |
| 1324 | ending = self._CRLF |
| 1325 | pos = crpos |
| 1326 | endpos = pos + 2 |
| 1327 | break |
| 1328 | else: |
| 1329 | # Found \r |
| 1330 | pos = crpos |
| 1331 | endpos = pos + 1 |
| 1332 | ending = self._CR |
| 1333 | break |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1334 | else: |
Guido van Rossum | 8358db2 | 2007-08-18 21:39:55 +0000 | [diff] [blame] | 1335 | # non-universal |
| 1336 | pos = line.find(self._readnl) |
| 1337 | if pos >= 0: |
| 1338 | endpos = pos+len(self._readnl) |
| 1339 | ending = self._nlflag(self._readnl) |
| 1340 | break |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1341 | |
| 1342 | # No line ending seen yet - get more data |
Guido van Rossum | 8358db2 | 2007-08-18 21:39:55 +0000 | [diff] [blame] | 1343 | more_line = '' |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1344 | while True: |
Guido van Rossum | cba608c | 2007-04-11 14:19:59 +0000 | [diff] [blame] | 1345 | readahead, pending = self._read_chunk() |
| 1346 | more_line = pending |
| 1347 | if more_line or not readahead: |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1348 | break |
Guido van Rossum | 8358db2 | 2007-08-18 21:39:55 +0000 | [diff] [blame] | 1349 | if more_line: |
| 1350 | line += more_line |
| 1351 | else: |
| 1352 | # end of file |
| 1353 | self._pending = '' |
| 1354 | self._snapshot = None |
| 1355 | if cr_eof: |
| 1356 | self._seennl |= self._CR |
| 1357 | return line[:-1] + '\n' |
| 1358 | else: |
| 1359 | return line |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1360 | |
Guido van Rossum | 8358db2 | 2007-08-18 21:39:55 +0000 | [diff] [blame] | 1361 | self._pending = line[endpos:] |
| 1362 | if self._readtranslate: |
| 1363 | self._seennl |= ending |
| 1364 | if ending != self._LF: |
| 1365 | return line[:pos] + '\n' |
| 1366 | else: |
| 1367 | return line[:endpos] |
Guido van Rossum | 78892e4 | 2007-04-06 17:31:18 +0000 | [diff] [blame] | 1368 | else: |
Guido van Rossum | 8358db2 | 2007-08-18 21:39:55 +0000 | [diff] [blame] | 1369 | return line[:endpos] |
Guido van Rossum | 024da5c | 2007-05-17 23:59:11 +0000 | [diff] [blame] | 1370 | |
Guido van Rossum | 8358db2 | 2007-08-18 21:39:55 +0000 | [diff] [blame] | 1371 | def _replacenl(self, data): |
| 1372 | # Replace newlines in data as needed and record that they have |
| 1373 | # been seen. |
| 1374 | if not self._readtranslate: |
| 1375 | return data |
| 1376 | if self._readuniversal: |
| 1377 | crlf = data.count('\r\n') |
| 1378 | cr = data.count('\r') - crlf |
| 1379 | lf = data.count('\n') - crlf |
| 1380 | self._seennl |= (lf and self._LF) | (cr and self._CR) \ |
| 1381 | | (crlf and self._CRLF) |
| 1382 | if crlf: |
| 1383 | data = data.replace("\r\n", "\n") |
| 1384 | if cr: |
| 1385 | data = data.replace("\r", "\n") |
| 1386 | elif self._readnl == '\n': |
| 1387 | # Only need to detect if \n was seen. |
| 1388 | if data.count('\n'): |
| 1389 | self._seennl |= self._LF |
| 1390 | else: |
| 1391 | newdata = data.replace(self._readnl, '\n') |
| 1392 | if newdata is not data: |
| 1393 | self._seennl |= self._nlflag(self._readnl) |
| 1394 | data = newdata |
| 1395 | return data |
| 1396 | |
| 1397 | _LF = 1 |
| 1398 | _CR = 2 |
| 1399 | _CRLF = 4 |
| 1400 | @property |
| 1401 | def newlines(self): |
| 1402 | return (None, |
| 1403 | "\n", |
| 1404 | "\r", |
| 1405 | ("\r", "\n"), |
| 1406 | "\r\n", |
| 1407 | ("\n", "\r\n"), |
| 1408 | ("\r", "\r\n"), |
| 1409 | ("\r", "\n", "\r\n") |
| 1410 | )[self._seennl] |
| 1411 | |
| 1412 | def _nlflag(self, nlstr): |
| 1413 | return [None, "\n", "\r", None, "\r\n"].index(nlstr) |
Guido van Rossum | 024da5c | 2007-05-17 23:59:11 +0000 | [diff] [blame] | 1414 | |
| 1415 | class StringIO(TextIOWrapper): |
| 1416 | |
| 1417 | # XXX This is really slow, but fully functional |
| 1418 | |
Guido van Rossum | e86254e | 2007-08-29 18:31:16 +0000 | [diff] [blame] | 1419 | def __init__(self, initial_value="", encoding="utf-8", newline="\n"): |
Guido van Rossum | 3e1f85e | 2007-07-27 18:03:11 +0000 | [diff] [blame] | 1420 | super(StringIO, self).__init__(BytesIO(), |
| 1421 | encoding=encoding, |
| 1422 | newline=newline) |
Guido van Rossum | 024da5c | 2007-05-17 23:59:11 +0000 | [diff] [blame] | 1423 | if initial_value: |
Guido van Rossum | 3172c5d | 2007-10-16 18:12:55 +0000 | [diff] [blame] | 1424 | if not isinstance(initial_value, str): |
Guido van Rossum | 34d1928 | 2007-08-09 01:03:29 +0000 | [diff] [blame] | 1425 | initial_value = str(initial_value) |
Guido van Rossum | 024da5c | 2007-05-17 23:59:11 +0000 | [diff] [blame] | 1426 | self.write(initial_value) |
| 1427 | self.seek(0) |
| 1428 | |
| 1429 | def getvalue(self): |
Guido van Rossum | 34d1928 | 2007-08-09 01:03:29 +0000 | [diff] [blame] | 1430 | self.flush() |
Guido van Rossum | 3e1f85e | 2007-07-27 18:03:11 +0000 | [diff] [blame] | 1431 | return self.buffer.getvalue().decode(self._encoding) |