SF patch #100740: Add optional size arguments to .readline() and
.readlines() methods. Inspired by a patch from Wolfgang Grafen,
though this version of the patch was completely rewritten from his
code.
diff --git a/Lib/gzip.py b/Lib/gzip.py
index 43501d4..0c9642b 100644
--- a/Lib/gzip.py
+++ b/Lib/gzip.py
@@ -5,10 +5,8 @@
# based on Andrew Kuchling's minigzip.py distributed with the zlib module
-import time
-import string
+import string, struct, sys, time
import zlib
-import struct
import __builtin__
FTEXT, FHCRC, FEXTRA, FNAME, FCOMMENT = 1, 2, 4, 8, 16
@@ -175,7 +173,8 @@
if self.fileobj is None: raise EOFError, "Reached EOF"
if self._new_member:
- # If the _new_member flag is set, we have to
+ # If the _new_member flag is set, we have to
+ # jump to the next member, if there is one.
#
# First, check if we're at the end of the file;
# if so, it's time to stop; no more members to read.
@@ -273,27 +272,46 @@
def isatty(self):
return 0
- def readline(self):
+ def readline(self, size=-1):
+ if size < 0: size = sys.maxint
bufs = []
- readsize = 100
+ orig_size = size
+ readsize = min(100, size) # Read from the file in small chunks
while 1:
+ if size == 0:
+ return string.join(bufs, '') # Return resulting line
+
c = self.read(readsize)
i = string.find(c, '\n')
- if i >= 0 or c == '':
- bufs.append(c[:i+1])
- self._unread(c[i+1:])
- return string.join(bufs, '')
- bufs.append(c)
- readsize = readsize * 2
+ if size is not None:
+ # We set i=size to break out of the loop under two
+ # conditions: 1) there's no newline, and the chunk is
+ # larger than size, or 2) there is a newline, but the
+ # resulting line would be longer than 'size'.
+ if i==-1 and len(c) > size: i=size-1
+ elif size <= i: i = size -1
- def readlines(self, ignored=None):
- buf = self.read()
- lines = string.split(buf, '\n')
- for i in range(len(lines)-1):
- lines[i] = lines[i] + '\n'
- if lines and not lines[-1]:
- del lines[-1]
- return lines
+ if i >= 0 or c == '':
+ bufs.append(c[:i+1]) # Add portion of last chunk
+ self._unread(c[i+1:]) # Push back rest of chunk
+ return string.join(bufs, '') # Return resulting line
+
+ # Append chunk to list, decrease 'size',
+ bufs.append(c)
+ size = size - len(c)
+ readsize = min(size, readsize * 2)
+
+ def readlines(self, sizehint=0):
+ # Negative numbers result in reading all the lines
+ if sizehint <= 0: sizehint = sys.maxint
+ L = []
+ while sizehint > 0:
+ line = self.readline()
+ if line == "": break
+ L.append( line )
+ sizehint = sizehint - len(line)
+
+ return L
def writelines(self, L):
for line in L: