mirror of
https://github.com/python-pillow/Pillow.git
synced 2024-11-10 19:56:47 +03:00
31c454b925
This is, I guess, a few things the Python devs were just fed up with.
* "while 1" is now "while True"
* Types are compared with isinstance instead of ==
* Sort a list in one go with sorted()
My own twist is to also replace type('') with str, type(()) with tuple,
type([]) with list, type(1) with int, and type(5000.0) with float.
117 lines
2.5 KiB
Python
117 lines
2.5 KiB
Python
#
|
|
# 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.
|
|
#
|
|
|
|
##
|
|
# A file object that provides read access to a part of an existing
|
|
# file (for example a TAR file).
|
|
|
|
class ContainerIO:
|
|
|
|
##
|
|
# Create file object.
|
|
#
|
|
# @param file Existing file.
|
|
# @param offset Start of region, in bytes.
|
|
# @param length Size of region, in bytes.
|
|
|
|
def __init__(self, file, offset, length):
|
|
self.fh = file
|
|
self.pos = 0
|
|
self.offset = offset
|
|
self.length = length
|
|
self.fh.seek(offset)
|
|
|
|
##
|
|
# Always false.
|
|
|
|
def isatty(self):
|
|
return 0
|
|
|
|
##
|
|
# 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.
|
|
|
|
def seek(self, offset, mode = 0):
|
|
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)
|
|
|
|
##
|
|
# Get current file pointer.
|
|
#
|
|
# @return Offset from start of region, in bytes.
|
|
|
|
def tell(self):
|
|
return self.pos
|
|
|
|
##
|
|
# Read data.
|
|
#
|
|
# @def read(bytes=0)
|
|
# @param bytes Number of bytes to read. If omitted or zero,
|
|
# read until end of region.
|
|
# @return An 8-bit string.
|
|
|
|
def read(self, n = 0):
|
|
if n:
|
|
n = min(n, self.length - self.pos)
|
|
else:
|
|
n = self.length - self.pos
|
|
if not n: # EOF
|
|
return ""
|
|
self.pos = self.pos + n
|
|
return self.fh.read(n)
|
|
|
|
##
|
|
# Read a line of text.
|
|
#
|
|
# @return An 8-bit string.
|
|
|
|
def readline(self):
|
|
s = ""
|
|
while True:
|
|
c = self.read(1)
|
|
if not c:
|
|
break
|
|
s = s + c
|
|
if c == "\n":
|
|
break
|
|
return s
|
|
|
|
##
|
|
# Read multiple lines of text.
|
|
#
|
|
# @return A list of 8-bit strings.
|
|
|
|
def readlines(self):
|
|
l = []
|
|
while True:
|
|
s = self.readline()
|
|
if not s:
|
|
break
|
|
l.append(s)
|
|
return l
|