Fix #75776: Flushing streams with compression filter is broken #6703
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First, the `bzip2.compress` filter has the same issue as `zlib.deflate` so we port the respective fix[1] to ext/bz2. Second, there is still an issue, if a stream with an attached compression filter is flushed before it is closed, without any writes in between. In that case, the compression is never finalized. We fix this by enforcing a `_php_stream_flush()` with the `closing` flag set in `_php_stream_free()`, whenever a write filter is attached. This call is superfluous for most write filters, but does not hurt, even when it is unnecessary. [1] <http://git.php.net/?p=php-src.git;a=commit;h=20e75329f2adb11dd231852c061926d0e4080929>
nikic
approved these changes
Feb 22, 2021
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First, the
bzip2.compressfilter has the same issue aszlib.deflateso we port the respective fix[1] to ext/bz2.
Second, there is still an issue, if a stream with an attached
compression filter is flushed before it is closed, without any writes
in between. In that case, the compression is never finalized. We fix
this by enforcing a
_php_stream_flush()with theclosingflag setin
_php_stream_free(), whenever a write filter is attached. Thiscall is superfluous for most write filters, but does not hurt, even
when it is unnecessary.
[1] http://git.php.net/?p=php-src.git;a=commit;h=20e75329f2adb11dd231852c061926d0e4080929