ext/zlib: honor preset dictionary for raw inflate with non-default window#105
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ext/zlib: honor preset dictionary for raw inflate with non-default window#105iliaal wants to merge 1 commit into
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…ndow inflate_init() applies the preset dictionary eagerly for raw streams via inflateSetDictionary(), gated on encoding == PHP_ZLIB_ENCODING_RAW. But encoding is first adjusted by the window size (encoding += 15 - window), so a raw stream with a non-default window no longer equals PHP_ZLIB_ENCODING_RAW and the dictionary is silently dropped; raw streams carry no header and never emit Z_NEED_DICT, so inflate_add()'s deferred path never applies it either. Gate on the pre-adjustment encoding. The deflate side already applies the dictionary unconditionally, so the roundtrip was broken for this case.
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Submitted upstream as php#22381. |
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inflate_init() applies a preset dictionary eagerly for raw streams via inflateSetDictionary(), gated on
encoding == PHP_ZLIB_ENCODING_RAW. Butencodingis first adjusted by the window size (encoding += 15 - window), so a raw stream opened with a non-default window no longer compares equal to PHP_ZLIB_ENCODING_RAW and the dictionary is silently dropped. Raw streams carry no zlib header and never emit Z_NEED_DICT, so inflate_add()'s deferred dictionary path never applies it either. The deflate side applies the dictionary unconditionally, sodeflate_init(ZLIB_ENCODING_RAW, ['window'=>10, 'dictionary'=>$d])+ the matching inflate produced a data error instead of a roundtrip. Gate on the pre-adjustment encoding.