mirror of
https://github.com/python/cpython.git
synced 2024-11-27 11:55:13 +08:00
54f22ed30b
who writes: Here is batch 2, as a big collection of CVS context diffs. Along with moving comments into docstrings, i've added a couple of missing docstrings and attempted to make sure more module docstrings begin with a one-line summary. I did not add docstrings to the methods in profile.py for fear of upsetting any careful optimizations there, though i did move class documentation into class docstrings. The convention i'm using is to leave credits/version/copyright type of stuff in # comments, and move the rest of the descriptive stuff about module usage into module docstrings. Hope this is okay.
164 lines
3.9 KiB
Python
164 lines
3.9 KiB
Python
"""A readline()-style interface to the parts of a multipart message.
|
|
|
|
The MultiFile class makes each part of a multipart message "feel" like
|
|
an ordinary file, as long as you use fp.readline(). Allows recursive
|
|
use, for nested multipart messages. Probably best used together
|
|
with module mimetools.
|
|
|
|
Suggested use:
|
|
|
|
real_fp = open(...)
|
|
fp = MultiFile(real_fp)
|
|
|
|
"read some lines from fp"
|
|
fp.push(separator)
|
|
while 1:
|
|
"read lines from fp until it returns an empty string" (A)
|
|
if not fp.next(): break
|
|
fp.pop()
|
|
"read remaining lines from fp until it returns an empty string"
|
|
|
|
The latter sequence may be used recursively at (A).
|
|
It is also allowed to use multiple push()...pop() sequences.
|
|
|
|
If seekable is given as 0, the class code will not do the bookeeping
|
|
it normally attempts in order to make seeks relative to the beginning of the
|
|
current file part. This may be useful when using MultiFile with a non-
|
|
seekable stream object.
|
|
"""
|
|
|
|
import sys
|
|
import string
|
|
|
|
Error = 'multifile.Error'
|
|
|
|
class MultiFile:
|
|
|
|
seekable = 0
|
|
|
|
def __init__(self, fp, seekable=1):
|
|
self.fp = fp
|
|
self.stack = [] # Grows down
|
|
self.level = 0
|
|
self.last = 0
|
|
if seekable:
|
|
self.seekable = 1
|
|
self.start = self.fp.tell()
|
|
self.posstack = [] # Grows down
|
|
|
|
def tell(self):
|
|
if self.level > 0:
|
|
return self.lastpos
|
|
return self.fp.tell() - self.start
|
|
|
|
def seek(self, pos, whence=0):
|
|
here = self.tell()
|
|
if whence:
|
|
if whence == 1:
|
|
pos = pos + here
|
|
elif whence == 2:
|
|
if self.level > 0:
|
|
pos = pos + self.lastpos
|
|
else:
|
|
raise Error, "can't use whence=2 yet"
|
|
if not 0 <= pos <= here or \
|
|
self.level > 0 and pos > self.lastpos:
|
|
raise Error, 'bad MultiFile.seek() call'
|
|
self.fp.seek(pos + self.start)
|
|
self.level = 0
|
|
self.last = 0
|
|
|
|
def readline(self):
|
|
if self.level > 0:
|
|
return ''
|
|
line = self.fp.readline()
|
|
# Real EOF?
|
|
if not line:
|
|
self.level = len(self.stack)
|
|
self.last = (self.level > 0)
|
|
if self.last:
|
|
raise Error, 'sudden EOF in MultiFile.readline()'
|
|
return ''
|
|
assert self.level == 0
|
|
# Fast check to see if this is just data
|
|
if self.is_data(line):
|
|
return line
|
|
else:
|
|
# Ignore trailing whitespace on marker lines
|
|
k = len(line) - 1;
|
|
while line[k] in string.whitespace:
|
|
k = k - 1
|
|
marker = line[:k+1]
|
|
# No? OK, try to match a boundary.
|
|
# Return the line (unstripped) if we don't.
|
|
for i in range(len(self.stack)):
|
|
sep = self.stack[i]
|
|
if marker == self.section_divider(sep):
|
|
self.last = 0
|
|
break
|
|
elif marker == self.end_marker(sep):
|
|
self.last = 1
|
|
break
|
|
else:
|
|
return line
|
|
# We only get here if we see a section divider or EOM line
|
|
if self.seekable:
|
|
self.lastpos = self.tell() - len(line)
|
|
self.level = i+1
|
|
if self.level > 1:
|
|
raise Error,'Missing endmarker in MultiFile.readline()'
|
|
return ''
|
|
|
|
def readlines(self):
|
|
list = []
|
|
while 1:
|
|
line = self.readline()
|
|
if not line: break
|
|
list.append(line)
|
|
return list
|
|
|
|
def read(self): # Note: no size argument -- read until EOF only!
|
|
return string.joinfields(self.readlines(), '')
|
|
|
|
def next(self):
|
|
while self.readline(): pass
|
|
if self.level > 1 or self.last:
|
|
return 0
|
|
self.level = 0
|
|
self.last = 0
|
|
if self.seekable:
|
|
self.start = self.fp.tell()
|
|
return 1
|
|
|
|
def push(self, sep):
|
|
if self.level > 0:
|
|
raise Error, 'bad MultiFile.push() call'
|
|
self.stack.insert(0, sep)
|
|
if self.seekable:
|
|
self.posstack.insert(0, self.start)
|
|
self.start = self.fp.tell()
|
|
|
|
def pop(self):
|
|
if self.stack == []:
|
|
raise Error, 'bad MultiFile.pop() call'
|
|
if self.level <= 1:
|
|
self.last = 0
|
|
else:
|
|
abslastpos = self.lastpos + self.start
|
|
self.level = max(0, self.level - 1)
|
|
del self.stack[0]
|
|
if self.seekable:
|
|
self.start = self.posstack[0]
|
|
del self.posstack[0]
|
|
if self.level > 0:
|
|
self.lastpos = abslastpos - self.start
|
|
|
|
def is_data(self, line):
|
|
return line[:2] <> '--'
|
|
|
|
def section_divider(self, str):
|
|
return "--" + str
|
|
|
|
def end_marker(self, str):
|
|
return "--" + str + "--"
|