fixed ZSTD_initCStream_advanced() behavior, which depends on contentSizeFlag,

and a stream fuzzer test, which was incorrect
(relied on 0 being unconditionnally transformed into `ZSTD_CONTENTSIZE_UNKNOWN`)

diff --git a/lib/compress/zstd_compress.c b/lib/compress/zstd_compress.c
index 49b532b945c4f33b9440ed4ba1ddbf70392ed955..4ceba415c77a851080be032cf5e8a0a500bf3eb3 100644 (file)
--- a/lib/compress/zstd_compress.c
+++ b/lib/compress/zstd_compress.c
@@ -822,9 +822,8 @@ static size_t ZSTD_resetCCtx_internal(ZSTD_CCtx* zc,
                                       ZSTD_compResetPolicy_e const crp,
                                       ZSTD_buffered_policy_e const zbuff)
 {
-    DEBUGLOG(4, "ZSTD_resetCCtx_internal");
+    DEBUGLOG(4, "ZSTD_resetCCtx_internal: pledgedSrcSize=%u", (U32)pledgedSrcSize);
     assert(!ZSTD_isError(ZSTD_checkCParams(params.cParams)));
-    DEBUGLOG(4, "pledgedSrcSize: %u", (U32)pledgedSrcSize);
 
     if (crp == ZSTDcrp_continue) {
         if (ZSTD_equivalentParams(params, zc->appliedParams)) {
@@ -2500,12 +2499,15 @@ static size_t ZSTD_resetCStream_internal(ZSTD_CStream* zcs,
     return 0;   /* ready to go */
 }
 
+/* ZSTD_resetCStream():
+ * pledgedSrcSize == 0 means "unknown" */
 size_t ZSTD_resetCStream(ZSTD_CStream* zcs, unsigned long long pledgedSrcSize)
 {
     ZSTD_CCtx_params params = zcs->requestedParams;
-    params.fParams.contentSizeFlag = (pledgedSrcSize > 0);
+    DEBUGLOG(4, "ZSTD_resetCStream: pledgedSrcSize = %u", (U32)pledgedSrcSize);
+    if (pledgedSrcSize==0) pledgedSrcSize = ZSTD_CONTENTSIZE_UNKNOWN;
+    params.fParams.contentSizeFlag = 1;
     params.cParams = ZSTD_getCParamsFromCCtxParams(params, pledgedSrcSize, 0);
-    DEBUGLOG(4, "ZSTD_resetCStream");
     return ZSTD_resetCStream_internal(zcs, NULL, 0, ZSTD_dm_auto, zcs->cdict, params, pledgedSrcSize);
 }
 
@@ -2572,13 +2574,19 @@ size_t ZSTD_initCStream_usingCDict(ZSTD_CStream* zcs, const ZSTD_CDict* cdict)
     return ZSTD_initCStream_usingCDict_advanced(zcs, cdict, fParams, 0);  /* note : will check that cdict != NULL */
 }
 
+/* ZSTD_initCStream_advanced() :
+ * pledgedSrcSize is optional: it can be 0, which means "unknown" if contentSizeFlag is set, or "unknown" if contentSizeFlag is not set. */
 size_t ZSTD_initCStream_advanced(ZSTD_CStream* zcs,
                                  const void* dict, size_t dictSize,
                                  ZSTD_parameters params, unsigned long long pledgedSrcSize)
 {
     ZSTD_CCtx_params const cctxParams =
             ZSTD_assignParamsToCCtxParams(zcs->requestedParams, params);
+    DEBUGLOG(4, "ZSTD_initCStream_advanced: pledgedSrcSize=%u, flag=%u",
+            (U32)pledgedSrcSize, params.fParams.contentSizeFlag);
     CHECK_F( ZSTD_checkCParams(params.cParams) );
+    if ((pledgedSrcSize==0) && (params.fParams.contentSizeFlag==0))
+        pledgedSrcSize = ZSTD_CONTENTSIZE_UNKNOWN;
     return ZSTD_initCStream_internal(zcs, dict, dictSize, NULL, cctxParams, pledgedSrcSize);
 }
 

diff --git a/lib/zstd.h b/lib/zstd.h
index 7fafdbfc330be9831a5a7d1077bfc5360d055b6d..2866866be043037a8a0be5ef0a2ce2a651931cce 100644 (file)
--- a/lib/zstd.h
+++ b/lib/zstd.h
@@ -734,7 +734,7 @@ ZSTDLIB_API ZSTD_CStream* ZSTD_initStaticCStream(void* workspace, size_t workspa
 ZSTDLIB_API size_t ZSTD_initCStream_srcSize(ZSTD_CStream* zcs, int compressionLevel, unsigned long long pledgedSrcSize);   /**< pledgedSrcSize must be correct, a size of 0 means unknown.  for a frame size of 0 use initCStream_advanced */
 ZSTDLIB_API size_t ZSTD_initCStream_usingDict(ZSTD_CStream* zcs, const void* dict, size_t dictSize, int compressionLevel); /**< creates of an internal CDict (incompatible with static CCtx), except if dict == NULL or dictSize < 8, in which case no dict is used. Note: dict is loaded with ZSTD_dm_auto (treated as a full zstd dictionary if it begins with ZSTD_MAGIC_DICTIONARY, else as raw content) and ZSTD_dlm_byCopy.*/
 ZSTDLIB_API size_t ZSTD_initCStream_advanced(ZSTD_CStream* zcs, const void* dict, size_t dictSize,
-                                             ZSTD_parameters params, unsigned long long pledgedSrcSize);  /**< pledgedSrcSize is optional and can be 0 (meaning unknown). note: if the contentSizeFlag is set, pledgedSrcSize == 0 means the source size is actually 0. dict is loaded with ZSTD_dm_auto and ZSTD_dlm_byCopy. */
+                                             ZSTD_parameters params, unsigned long long pledgedSrcSize);  /**< pledgedSrcSize is optional: it can be 0, which means "unknown" if contentSizeFlag is set, or "unknown" if contentSizeFlag is not set. dict is loaded with ZSTD_dm_auto and ZSTD_dlm_byCopy. */
 ZSTDLIB_API size_t ZSTD_initCStream_usingCDict(ZSTD_CStream* zcs, const ZSTD_CDict* cdict);  /**< note : cdict will just be referenced, and must outlive compression session */
 ZSTDLIB_API size_t ZSTD_initCStream_usingCDict_advanced(ZSTD_CStream* zcs, const ZSTD_CDict* cdict, ZSTD_frameParameters fParams, unsigned long long pledgedSrcSize);  /**< same as ZSTD_initCStream_usingCDict(), with control over frame parameters */
 

diff --git a/tests/zstreamtest.c b/tests/zstreamtest.c
index 36eede2939ccef8572c6b11e1bfc0de5f079c4c1..3aea22709aebdbe66cb203e4266cffdc171e0c97 100644 (file)
--- a/tests/zstreamtest.c
+++ b/tests/zstreamtest.c
@@ -559,7 +559,7 @@ static int basicUnitTests(U32 seed, double compressibility, ZSTD_customMem custo
     DISPLAYLEVEL(3, "test%3i : ZSTD_initCStream_advanced with pledgedSrcSize=0 and dict : ", testNb++);
     {   ZSTD_parameters params = ZSTD_getParams(5, 0, 0);
         params.fParams.contentSizeFlag = 1;
-        CHECK_Z( ZSTD_initCStream_advanced(zc, dictionary.start, dictionary.filled, params, 0) );
+        CHECK_Z( ZSTD_initCStream_advanced(zc, dictionary.start, dictionary.filled, params, 0 /* pledgedSrcSize==0 means "empty" when params.fParams.contentSizeFlag is set */) );
     } /* cstream advanced shall write content size = 0 */
     inBuff.src = CNBuffer;
     inBuff.size = 0;
@@ -833,10 +833,11 @@ static int fuzzerTests(U32 seed, U32 nbTests, unsigned startTest, double compres
             {   size_t const dictStart = FUZ_rand(&lseed) % (srcBufferSize - dictSize);
                 dict = srcBuffer + dictStart;
             }
-            {   U64 const pledgedSrcSize = (FUZ_rand(&lseed) & 3) ? 0 : maxTestSize;
+            {   U64 const pledgedSrcSize = (FUZ_rand(&lseed) & 3) ? ZSTD_CONTENTSIZE_UNKNOWN : maxTestSize;
                 ZSTD_parameters params = ZSTD_getParams(cLevel, pledgedSrcSize, dictSize);
                 params.fParams.checksumFlag = FUZ_rand(&lseed) & 1;
                 params.fParams.noDictIDFlag = FUZ_rand(&lseed) & 1;
+                params.fParams.contentSizeFlag = FUZ_rand(&lseed) & 1;
                 CHECK_Z ( ZSTD_initCStream_advanced(zc, dict, dictSize, params, pledgedSrcSize) );
         }   }