zstd/compress/zstd_compress_internal.h

189     U32 lowLimit;              /* below that point, no more valid data */
892     - ZSTD_CURRENT_MAX)          /* Maximum beginning lowLimit */
903     window->lowLimit = end;
910            window.lowLimit == ZSTD_WINDOW_START_INDEX &&
920     return window.lowLimit < window.dictLimit;
1019      *    lowLimit > (3<<29) ==> current > 3<<29 + 1<<windowLog
1033      * 3. (cctx->lowLimit + 1<<windowLog) < 1<<32:
1062     if (window->lowLimit < correction + ZSTD_WINDOW_START_INDEX) {
1063         window->lowLimit = ZSTD_WINDOW_START_INDEX;
1065         window->lowLimit -= correction;
1076     /* Ensure that lowLimit and dictLimit didn't underflow. */
1077     assert(window->lowLimit <= newCurrent);
1082     DEBUGLOG(4, "Correction of 0x%x bytes to lowLimit=0x%x", correction,
1083              window->lowLimit);
1089  * Updates lowLimit so that:
1090  *    (srcEnd - base) - lowLimit == maxDist + loadedDictEnd
1092  * It ensures index is valid as long as index >= lowLimit.
1100  * If loadedDictEndPtr is not NULL, we set it to zero after updating lowLimit.
1105  * In normal dict mode, the dictionary lies between lowLimit and dictLimit.
1106  * In dictMatchState mode, lowLimit and dictLimit are the same,
1137         if (window->lowLimit < newLowLimit) window->lowLimit = newLowLimit;
1138         if (window->dictLimit < window->lowLimit) {
1139             DEBUGLOG(5, "Update dictLimit to match lowLimit, from %u to %u",
1140                         (unsigned)window->dictLimit, (unsigned)window->lowLimit);
1141             window->dictLimit = window->lowLimit;
1190     window->lowLimit = ZSTD_WINDOW_START_INDEX;     /* it ensures first and later CCtx usages compress the same */
1218         window->lowLimit = window->dictLimit;
1224         if (window->dictLimit - window->lowLimit < HASH_READ_SIZE) window->lowLimit = window->dictLimit;   /* too small extDict */
1229     if ( (ip+srcSize > window->dictBase + window->lowLimit)
1233         window->lowLimit = lowLimitMax;
1234         DEBUGLOG(5, "Overlapping extDict and input : new lowLimit = %u", window->lowLimit);
1245     U32 const lowestValid = ms->window.lowLimit;