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Diffstat (limited to '.venv/lib/python3.12/site-packages/PIL/ContainerIO.py')
-rw-r--r-- | .venv/lib/python3.12/site-packages/PIL/ContainerIO.py | 173 |
1 files changed, 173 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/PIL/ContainerIO.py b/.venv/lib/python3.12/site-packages/PIL/ContainerIO.py new file mode 100644 index 00000000..ec9e66c7 --- /dev/null +++ b/.venv/lib/python3.12/site-packages/PIL/ContainerIO.py @@ -0,0 +1,173 @@ +# +# The Python Imaging Library. +# $Id$ +# +# a class to read from a container file +# +# History: +# 1995-06-18 fl Created +# 1995-09-07 fl Added readline(), readlines() +# +# Copyright (c) 1997-2001 by Secret Labs AB +# Copyright (c) 1995 by Fredrik Lundh +# +# See the README file for information on usage and redistribution. +# +from __future__ import annotations + +import io +from collections.abc import Iterable +from typing import IO, AnyStr, NoReturn + + +class ContainerIO(IO[AnyStr]): + """ + A file object that provides read access to a part of an existing + file (for example a TAR file). + """ + + def __init__(self, file: IO[AnyStr], offset: int, length: int) -> None: + """ + Create file object. + + :param file: Existing file. + :param offset: Start of region, in bytes. + :param length: Size of region, in bytes. + """ + self.fh: IO[AnyStr] = file + self.pos = 0 + self.offset = offset + self.length = length + self.fh.seek(offset) + + ## + # Always false. + + def isatty(self) -> bool: + return False + + def seekable(self) -> bool: + return True + + def seek(self, offset: int, mode: int = io.SEEK_SET) -> int: + """ + Move file pointer. + + :param offset: Offset in bytes. + :param mode: Starting position. Use 0 for beginning of region, 1 + for current offset, and 2 for end of region. You cannot move + the pointer outside the defined region. + :returns: Offset from start of region, in bytes. + """ + if mode == 1: + self.pos = self.pos + offset + elif mode == 2: + self.pos = self.length + offset + else: + self.pos = offset + # clamp + self.pos = max(0, min(self.pos, self.length)) + self.fh.seek(self.offset + self.pos) + return self.pos + + def tell(self) -> int: + """ + Get current file pointer. + + :returns: Offset from start of region, in bytes. + """ + return self.pos + + def readable(self) -> bool: + return True + + def read(self, n: int = -1) -> AnyStr: + """ + Read data. + + :param n: Number of bytes to read. If omitted, zero or negative, + read until end of region. + :returns: An 8-bit string. + """ + if n > 0: + n = min(n, self.length - self.pos) + else: + n = self.length - self.pos + if n <= 0: # EOF + return b"" if "b" in self.fh.mode else "" # type: ignore[return-value] + self.pos = self.pos + n + return self.fh.read(n) + + def readline(self, n: int = -1) -> AnyStr: + """ + Read a line of text. + + :param n: Number of bytes to read. If omitted, zero or negative, + read until end of line. + :returns: An 8-bit string. + """ + s: AnyStr = b"" if "b" in self.fh.mode else "" # type: ignore[assignment] + newline_character = b"\n" if "b" in self.fh.mode else "\n" + while True: + c = self.read(1) + if not c: + break + s = s + c + if c == newline_character or len(s) == n: + break + return s + + def readlines(self, n: int | None = -1) -> list[AnyStr]: + """ + Read multiple lines of text. + + :param n: Number of lines to read. If omitted, zero, negative or None, + read until end of region. + :returns: A list of 8-bit strings. + """ + lines = [] + while True: + s = self.readline() + if not s: + break + lines.append(s) + if len(lines) == n: + break + return lines + + def writable(self) -> bool: + return False + + def write(self, b: AnyStr) -> NoReturn: + raise NotImplementedError() + + def writelines(self, lines: Iterable[AnyStr]) -> NoReturn: + raise NotImplementedError() + + def truncate(self, size: int | None = None) -> int: + raise NotImplementedError() + + def __enter__(self) -> ContainerIO[AnyStr]: + return self + + def __exit__(self, *args: object) -> None: + self.close() + + def __iter__(self) -> ContainerIO[AnyStr]: + return self + + def __next__(self) -> AnyStr: + line = self.readline() + if not line: + msg = "end of region" + raise StopIteration(msg) + return line + + def fileno(self) -> int: + return self.fh.fileno() + + def flush(self) -> None: + self.fh.flush() + + def close(self) -> None: + self.fh.close() |