Fix bufferless API with attached dictionary

Fixes #3102.
2023-01-20 16:15:16 -08:00
parent 329169189c
commit b4467c1061
2 changed files with 27 additions and 1 deletions
@@ -1172,10 +1172,15 @@ ZSTD_checkDictValidity(const ZSTD_window_t* window,
                    (unsigned)blockEndIdx, (unsigned)maxDist, (unsigned)loadedDictEnd);
        assert(blockEndIdx >= loadedDictEnd);

-        if (blockEndIdx > loadedDictEnd + maxDist) {
+        if (blockEndIdx > loadedDictEnd + maxDist || loadedDictEnd != window->dictLimit) {
            /* On reaching window size, dictionaries are invalidated.
             * For simplification, if window size is reached anywhere within next block,
             * the dictionary is invalidated for the full block.
+             *
+             * We also have to invalidate the dictionary if ZSTD_window_update() has detected
+             * non-contiguous segments, which means that loadedDictEnd != window->dictLimit.
+             * loadedDictEnd may be 0, if forceWindow is true, but in that case we never use
+             * dictMatchState, so setting it to NULL is not a problem.
             */
            DEBUGLOG(6, "invalidating dictionary for current block (distance > windowSize)");
            *loadedDictEndPtr = 0;