Dev

lib/zstd.c

@@ -314,19 +314,15 @@ typedef struct ZSTD_Cctx_s
 #else
     U32 hashTable[HASH_TABLESIZE];
 #endif
+	BYTE buffer[WORKPLACESIZE];
 } cctxi_t;
 
 
 ZSTD_Cctx* ZSTD_createCCtx(void)
 {
     ZSTD_Cctx* ctx = (ZSTD_Cctx*) malloc( sizeof(ZSTD_Cctx) );
     if (ctx==NULL) return NULL;
-    ctx->seqStore.buffer = malloc(WORKPLACESIZE);
-    if (ctx->seqStore.buffer==NULL)
-    {
-        free(ctx);
-        return NULL;
-    }
+	ctx->seqStore.buffer = ctx->buffer;
     ctx->seqStore.offsetStart = (U32*) (ctx->seqStore.buffer);
     ctx->seqStore.offCodeStart = (BYTE*) (ctx->seqStore.offsetStart + (BLOCKSIZE>>2));
     ctx->seqStore.litStart = ctx->seqStore.offCodeStart + (BLOCKSIZE>>2);
@@ -344,7 +340,6 @@ void ZSTD_resetCCtx(ZSTD_Cctx* ctx)
 
 size_t ZSTD_freeCCtx(ZSTD_Cctx* ctx)
 {
-    free(ctx->seqStore.buffer);
     free(ctx);
     return 0;
 }
@@ -1239,7 +1234,7 @@ size_t ZSTD_decodeLiteralsBlock(void* ctx,
 }
 
 
-size_t ZSTD_decodeSeqHeaders(int* nbSeq, const BYTE** dumpsPtr,
+size_t ZSTD_decodeSeqHeaders(int* nbSeq, const BYTE** dumpsPtr, size_t* dumpsLengthPtr,
                          FSE_DTable* DTableLL, FSE_DTable* DTableML, FSE_DTable* DTableOffb,
                          const void* src, size_t srcSize)
 {
@@ -1272,6 +1267,7 @@ size_t ZSTD_decodeSeqHeaders(int* nbSeq, const BYTE** dumpsPtr,
     }
     *dumpsPtr = ip;
     ip += dumpsLength;
+    *dumpsLengthPtr = dumpsLength;
 
     /* check */
     if (ip > iend-3) return (size_t)-ZSTD_ERROR_SrcSize; /* min : all 3 are "raw", hence no header, but at least xxLog bits per type */
@@ -1356,6 +1352,7 @@ typedef struct {
     FSE_DState_t stateML;
     size_t prevOffset;
     const BYTE* dumps;
+    const BYTE* dumpsEnd;
 } seqState_t;
 
 
@@ -1366,19 +1363,23 @@ static void ZSTD_decodeSequence(seq_t* seq, seqState_t* seqState)
     size_t offset;
     size_t matchLength;
     const BYTE* dumps = seqState->dumps;
+    const BYTE* const de = seqState->dumpsEnd;
 
     /* Literal length */
     litLength = FSE_decodeSymbol(&(seqState->stateLL), &(seqState->DStream));
     prevOffset = litLength ? seq->offset : seqState->prevOffset;
     seqState->prevOffset = seq->offset;
     if (litLength == MaxLL)
     {
-        U32 add = *dumps++;
+        U32 add = dumps<de ? *dumps++ : 0;
         if (add < 255) litLength += add;
         else
         {
-            litLength = ZSTD_readLE32(dumps) & 0xFFFFFF;
-            dumps += 3;
+            if (dumps<=(de-3))
+            {
+                litLength = ZSTD_readLE32(dumps) & 0xFFFFFF;  /* no pb : dumps is always followed by seq tables > 1 byte */
+                dumps += 3;
+            }
         }
     }
 
@@ -1398,12 +1399,15 @@ static void ZSTD_decodeSequence(seq_t* seq, seqState_t* seqState)
     matchLength = FSE_decodeSymbol(&(seqState->stateML), &(seqState->DStream));
     if (matchLength == MaxML)
     {
-        U32 add = *dumps++;
+        U32 add = dumps<de ? *dumps++ : 0;
         if (add < 255) matchLength += add;
         else
         {
-            matchLength = ZSTD_readLE32(dumps) & 0xFFFFFF;   /* no pb : dumps is always followed by seq tables > 1 byte */
-            dumps += 3;
+            if (dumps<=(de-3))
+            {
+                matchLength = ZSTD_readLE32(dumps) & 0xFFFFFF;  /* no pb : dumps is always followed by seq tables > 1 byte */
+                dumps += 3;
+            }
         }
     }
     matchLength += MINMATCH;
@@ -1520,7 +1524,7 @@ static size_t ZSTD_decompressSequences(
     BYTE* const ostart = (BYTE* const)dst;
     BYTE* op = ostart;
     BYTE* const oend = ostart + maxDstSize;
-    size_t errorCode;
+    size_t errorCode, dumpsLength;
     const BYTE* litPtr = litStart;
     const BYTE* const litEnd = litStart + litSize;
     int nbSeq;
@@ -1531,7 +1535,7 @@ static size_t ZSTD_decompressSequences(
     BYTE* const base = (BYTE*) (dctx->base);
 
     /* Build Decoding Tables */
-    errorCode = ZSTD_decodeSeqHeaders(&nbSeq, &dumps,
+    errorCode = ZSTD_decodeSeqHeaders(&nbSeq, &dumps, &dumpsLength,
                                       DTableLL, DTableML, DTableOffb,
                                       ip, iend-ip);
     if (ZSTD_isError(errorCode)) return errorCode;
@@ -1544,14 +1548,15 @@ static size_t ZSTD_decompressSequences(
 
         memset(&sequence, 0, sizeof(sequence));
         seqState.dumps = dumps;
+        seqState.dumpsEnd = dumps + dumpsLength;
         seqState.prevOffset = 1;
         errorCode = FSE_initDStream(&(seqState.DStream), ip, iend-ip);
         if (FSE_isError(errorCode)) return (size_t)-ZSTD_ERROR_corruption;
         FSE_initDState(&(seqState.stateLL), &(seqState.DStream), DTableLL);
         FSE_initDState(&(seqState.stateOffb), &(seqState.DStream), DTableOffb);
         FSE_initDState(&(seqState.stateML), &(seqState.DStream), DTableML);
 
-        for ( ; (FSE_reloadDStream(&(seqState.DStream)) < FSE_DStream_completed) || (nbSeq>0) ; )
+        for ( ; (FSE_reloadDStream(&(seqState.DStream)) <= FSE_DStream_completed) && (nbSeq>0) ; )
         {
             size_t oneSeqSize;
             nbSeq--;
@@ -1562,7 +1567,7 @@ static size_t ZSTD_decompressSequences(
         }
 
         /* check if reached exact end */
-        if (FSE_reloadDStream(&(seqState.DStream)) > FSE_DStream_completed) return (size_t)-ZSTD_ERROR_corruption;   /* requested too much : data is corrupted */
+        if ( !FSE_endOfDStream(&(seqState.DStream)) ) return (size_t)-ZSTD_ERROR_corruption;   /* requested too much : data is corrupted */
         if (nbSeq<0) return (size_t)-ZSTD_ERROR_corruption;   /* requested too many sequences : data is corrupted */
 
         /* last literal segment */

lib/zstd_static.h

@@ -32,6 +32,11 @@
 */
 #pragma once
 
+/* The objects defined into this file should be considered experimental.
+ * They are not labelled stable, as their prototype may change in the future.
+ * You can use them for tests, provide feedback, or if you can endure risk of future changes.
+ */
+
 #if defined (__cplusplus)
 extern "C" {
 #endif
@@ -63,10 +68,9 @@ size_t ZSTD_nextSrcSizeToDecompress(ZSTD_Dctx* dctx);
 size_t ZSTD_decompressContinue(ZSTD_Dctx* dctx, void* dst, size_t maxDstSize, const void* src, size_t srcSize);
 /*
   Use above functions alternatively.
-  ZSTD_nextSrcSizeToDecompress() tells how much bytes to provide as input to ZSTD_decompressContinue().
-  This value is expected to be provided, precisely, as 'srcSize'.
-  Otherwise, compression will fail (result is an error code, which can be tested using ZSTD_isError() )
-  ZSTD_decompressContinue() result is the number of bytes regenerated within 'dst'.
+  ZSTD_nextSrcSizeToDecompress() tells how much bytes to provide as 'srcSize' to ZSTD_decompressContinue().
+  ZSTD_decompressContinue() will use previous data blocks to improve compresson if they are located prior to current block.
+  Result is the number of bytes regenerated within 'dst'.
   It can be zero, which is not an error; it just means ZSTD_decompressContinue() has decoded some header.
 */
 

programs/fullbench.c

@@ -229,7 +229,7 @@ typedef struct
 static size_t g_cSize = 0;
 
 extern size_t ZSTD_getcBlockSize(const void* src, size_t srcSize, blockProperties_t* bpPtr);
-extern size_t ZSTD_decodeSeqHeaders(int* nbSeq, const BYTE** dumpsPtr, FSE_DTable* DTableLL, FSE_DTable* DTableML, FSE_DTable* DTableOffb, const void* src, size_t srcSize);
+extern size_t ZSTD_decodeSeqHeaders(int* nbSeq, const BYTE** dumpsPtr, size_t* dumpsLengthPtr, FSE_DTable* DTableLL, FSE_DTable* DTableML, FSE_DTable* DTableOffb, const void* src, size_t srcSize);
 
 size_t local_ZSTD_compress(void* dst, size_t dstSize, void* buff2, const void* src, size_t srcSize)
 {
@@ -258,9 +258,10 @@ size_t local_ZSTD_decodeSeqHeaders(void* dst, size_t dstSize, void* buff2, const
 {
     U32 DTableML[1<<11], DTableLL[1<<10], DTableOffb[1<<9];
     const BYTE* dumps;
+    size_t length;
     int nbSeq;
     (void)src; (void)srcSize; (void)dst; (void)dstSize;
-    return ZSTD_decodeSeqHeaders(&nbSeq, &dumps, DTableLL, DTableML, DTableOffb, buff2, g_cSize);
+    return ZSTD_decodeSeqHeaders(&nbSeq, &dumps, &length, DTableLL, DTableML, DTableOffb, buff2, g_cSize);
 }
 
 size_t local_conditionalNull(void* dst, size_t dstSize, void* buff2, const void* src, size_t srcSize)