Rockbox open source high quality audio player as a Music Player Daemon
mpris
rockbox
mpd
libadwaita
audio
rust
zig
deno
FS#13299: Handle MP3 files with more than 128K of headers before audio data
Encountered a file with ~600K of ID3v1 headers.
Optimize the potential overhead by minimizing reverse seeks.
Change-Id: I972dbf1af1c36659f19c7ab4eed0b9149c642880
+15
-12
+15
-12
lib/rbcodec/metadata/mp3data.c
+15
-12
lib/rbcodec/metadata/mp3data.c
···
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* seek to this byte position and check if there is another
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* valid MPEG frame header of the same type. */
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struct mp3info info;
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-
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+
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/* Gather frame size from given header and seek to next
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* frame header. */
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-
mp3headerinfo(&info, header);
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+
if (!mp3headerinfo(&info, header)) continue;
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lseek(fd, info.frame_size-4, SEEK_CUR);
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+
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/* Read possible next frame header and seek back to last frame
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* headers byte position. */
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reference_header = 0;
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read_uint32be_mp3data(fd, &reference_header);
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//
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lseek(fd, -info.frame_size, SEEK_CUR);
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/* If the current header is of the same type as the previous
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* header we are finished. */
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if (headers_have_same_type(header, reference_header))
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+
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/* If the current header is of the same type as the previous
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* header we are finished. Rewind to frame data start. */
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if (headers_have_same_type(header, reference_header)) {
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lseek(fd, -info.frame_size, SEEK_CUR);
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break;
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}
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/* Otherwise keep going. Rewind to to start of "next" frame. */
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lseek(fd, -4, SEEK_CUR);
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pos += info.frame_size - 4;
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}
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}
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-
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+
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} while (true);
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*offset = pos - 4;
···
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{
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long tmp;
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unsigned long header = 0;
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header = __find_next_frame(fd, &tmp, 0x20000, 0, fileread, single_header);
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+
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header = __find_next_frame(fd, &tmp, 0x100000, 0, fileread, single_header);
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if(header == 0)
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return -1;
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