When there's no filename, don't make one up.
Added _test() that behaves (a bit) like gzip.
Fix a comment (*sequential* access is okay -- *random* access it out!)
diff --git a/Lib/gzip.py b/Lib/gzip.py
index fe2bf20..26d32aa 100644
--- a/Lib/gzip.py
+++ b/Lib/gzip.py
@@ -6,7 +6,7 @@
# implements a python function that reads and writes a gzipped file
# the user of the file doesn't have to worry about the compression,
-# but sequential access is not allowed
+# but random access is not allowed
# based on Andrew Kuchling's minigzip.py distributed with the zlib module
@@ -52,7 +52,7 @@
fileobj = self.myfileobj = __builtin__.open(filename, mode or 'r')
if filename is None:
if hasattr(fileobj, 'name'): filename = fileobj.name
- else: filename = 'GzippedFile'
+ else: filename = ''
if mode is None:
if hasattr(fileobj, 'mode'): mode = fileobj.mode
else: mode = 'r'
@@ -98,11 +98,16 @@
def _write_gzip_header(self):
self.fileobj.write('\037\213') # magic header
self.fileobj.write('\010') # compression method
- self.fileobj.write(chr(FNAME))
+ fname = self.filename[:-3]
+ flags = 0
+ if fname:
+ flags = FNAME
+ self.fileobj.write(chr(flags))
write32(self.fileobj, int(time.time()))
self.fileobj.write('\002')
self.fileobj.write('\377')
- self.fileobj.write(self.filename[:-3] + '\000')
+ if fname:
+ self.fileobj.write(fname + '\000')
def _init_read(self):
self.crc = zlib.crc32("")
@@ -132,12 +137,12 @@
# Read and discard a null-terminated string containing the filename
while (1):
s=self.fileobj.read(1)
- if s=='\000': break
+ if not s or s=='\000': break
if flag & FCOMMENT:
# Read and discard a null-terminated string containing a comment
while (1):
s=self.fileobj.read(1)
- if s=='\000': break
+ if not s or s=='\000': break
if flag & FHCRC:
self.fileobj.read(2) # Read & discard the 16-bit header CRC
@@ -251,3 +256,46 @@
def writelines(self, L):
for line in L:
self.write(line)
+
+
+def _test():
+ # Act like gzip; with -d, act like gunzip.
+ # The input file is not deleted, however, nor are any other gzip
+ # options or features supported.
+ import sys
+ args = sys.argv[1:]
+ decompress = args and args[0] == "-d"
+ if decompress:
+ args = args[1:]
+ if not args:
+ args = ["-"]
+ for arg in args:
+ if decompress:
+ if arg == "-":
+ f = GzipFile(filename="", mode="rb", fileobj=sys.stdin)
+ g = sys.stdout
+ else:
+ if arg[-3:] != ".gz":
+ print "filename doesn't end in .gz:", `arg`
+ continue
+ f = open(arg, "rb")
+ g = __builtin__.open(arg[:-3], "wb")
+ else:
+ if arg == "-":
+ f = sys.stdin
+ g = GzipFile(filename="", mode="wb", fileobj=sys.stdout)
+ else:
+ f = __builtin__.open(arg, "rb")
+ g = open(arg + ".gz", "wb")
+ while 1:
+ chunk = f.read(1024)
+ if not chunk:
+ break
+ g.write(chunk)
+ if g is not sys.stdout:
+ g.close()
+ if f is not sys.stdin:
+ f.close()
+
+if __name__ == '__main__':
+ _test()