_Stream.close(): Try to kill struct.pack() warnings when

writing the crc to file on the "PPC64 Debian trunk" buildbot
when running test_tarfile.

This is again a case where the native zlib crc is an unsigned
32-bit int, but the Python wrapper implicitly casts it to
signed C long, so that "the sign bit looks different" on
different platforms.
This commit is contained in:
Tim Peters 2006-08-02 05:20:08 +00:00
parent 99dfe3c411
commit a05f6e244a
1 changed files with 7 additions and 1 deletions

View File

@ -417,7 +417,13 @@ class _Stream:
self.fileobj.write(self.buf) self.fileobj.write(self.buf)
self.buf = "" self.buf = ""
if self.comptype == "gz": if self.comptype == "gz":
self.fileobj.write(struct.pack("<l", self.crc)) # The native zlib crc is an unsigned 32-bit integer, but
# the Python wrapper implicitly casts that to a signed C
# long. So, on a 32-bit box self.crc may "look negative",
# while the same crc on a 64-bit box may "look positive".
# To avoid irksome warnings from the `struct` module, force
# it to look positive on all boxes.
self.fileobj.write(struct.pack("<L", self.crc & 0xffffffffL))
self.fileobj.write(struct.pack("<L", self.pos & 0xffffFFFFL)) self.fileobj.write(struct.pack("<L", self.pos & 0xffffFFFFL))
if not self._extfileobj: if not self._extfileobj: