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minor comment change (unfinished description of new header format)

dev
Yann Collet 2016-06-04 18:40:55 +02:00
parent 0d31160b4e
commit 198d127b35
1 changed files with 17 additions and 0 deletions
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17
lib/decompress/zstd_decompress.c
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@ -205,6 +205,7 @@ void ZSTD_copyDCtx(ZSTD_DCtx* dstDCtx, const ZSTD_DCtx* srcDCtx)
/* Frame descriptor
// old
1 byte - Alloc :
bit 0-3 : windowLog - ZSTD_WINDOWLOG_ABSOLUTEMIN (see zstd_internal.h)
bit 4 : reserved for windowLog (must be zero)
@ -215,6 +216,22 @@ void ZSTD_copyDCtx(ZSTD_DCtx* dstDCtx, const ZSTD_DCtx* srcDCtx)
bit 0-1 : dictID (0, 1, 2 or 4 bytes)
bit 2-7 : reserved (must be zero)
// new
1 byte - Alloc :
bit 0-1 : dictID (0, 1, 2 or 4 bytes)
bit 2-4 : reserved (must be zero)
bit 5 : WindowLog skipped (note : if 1, then fcs > 0)
bit 6-7 : Frame content size : unknown, 1 byte, 2 bytes, 8 bytes
OR : 0-3 : no windowLog, 1, 2, 4, 8
4-7 : windowLog, 0, 2, 4, 8
1 byte - WindowLog (can be skipped if fcs>0)
bit 0-2 : octal Fractional (1/8th)
bit 3-7 : Power of 2, with 0 = 1 KB (up to 2 TB)
Optional : dictID (0, 1, 2 or 4 bytes)
Automatic adaptation
0 : no dictID