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Ryan FrancesconiandGitHub
3ace0483c0
RF64 and BW64 are the long forms of WAVE, used past 4 GB: each 32-bit size field holds a 0xffffffff sentinel and the real sizes live in a leading ds64 chunk. RIFF::WAV::File::isSupported() rejected them, but FileRef reaches the class by extension for any .wav and RIFF::File::read() never inspected the magic, so these files opened as valid. updateGlobalSize() then wrote a real 32-bit total over the sentinel at offset 4. Readers stop consulting ds64 once that field holds a number, so a 4.8 GB file measured 0.005958 sec and 1144 audio bytes after a tag save that returned true. Below 4 GB the tags were lost instead: the appended LIST landed inside the region read() had clamped the sentinel data chunk to, and a re-read found no properties. Worse, the append offset is last.offset + last.size with size truncated to 0xffffffff, so on a long file the new chunk was spliced into the middle of the audio — measured at offset 4294971392 on that same file, 4 GiB past the data chunk's start, displacing everything after it. Accept both magics, take the riff and data sizes from ds64, and write the sentinel back on save. Writing it unconditionally is what the format requires and also repairs a file an earlier version damaged: the same 4.8 GB file, clobbered and then saved through this path, read back at 25000.000000 sec and 4,800,000,000 bytes. The ds64 table of additional oversized chunks is not parsed — the data chunk has its own dedicated field and is the only one that is ever large — so any chunk listed there stays on the clamping path added in #1329, which this leaves untouched. Chunk::size becomes offset_t so the append offset is computed correctly. The struct is file-scope in rifffile.cpp and FilePrivate is only forward-declared, so no protected signature changes and no ABI break. chunkDataSize() still returns unsigned int, saturating rather than truncating; a new chunkDataSize64() carries the real value to WAV::Properties, which otherwise reports 0 s for a long file. AIFF is big-endian and has no long form, so RIFF::File's only other subclass cannot reach the new branch. tests/data/rf64.wav is 9,680 bytes and built by construction, not by an encoder; Core Audio reads it as RF64 at 0.050000 sec. The sentinels behave identically at any size, so a small fixture covers the detection failure, the sentinel overwrite and the repair.