ext/zlib: honor preset dictionary for raw inflate with non-default window#22381
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iliaal wants to merge 1 commit into
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ext/zlib: honor preset dictionary for raw inflate with non-default window#22381iliaal wants to merge 1 commit into
iliaal 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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inflate_init() applies a preset dictionary eagerly for raw streams, 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 matches and the dictionary is silently dropped. Raw streams carry no header and never emit Z_NEED_DICT, so the deferred application in inflate_add() never runs either. Gate on the pre-adjustment encoding; the deflate side already applies the dictionary unconditionally, so the roundtrip was broken for this case.