litBlockType_t is an enum

lib/common/zstd_internal.h

@@ -94,10 +94,7 @@ typedef enum { bt_compressed, bt_raw, bt_rle, bt_end } blockType_t;
 
 #define HufLog 12
 
-#define IS_HUF 0
+typedef enum { lbt_huffman, lbt_repeat, lbt_raw, lbt_rle } litBlockType_t;
-#define IS_PCH 1
-#define IS_RAW 2
-#define IS_RLE 3
 
 #define LONGNBSEQ 0x7F00
 

lib/compress/zstd_compress.c

@@ -575,15 +575,15 @@ static size_t ZSTD_noCompressLiterals (void* dst, size_t dstCapacity, const void
     switch(flSize)
     {
         case 1: /* 2 - 1 - 5 */
-            ostart[0] = (BYTE)((IS_RAW<<6) + (0<<5) + srcSize);
+            ostart[0] = (BYTE)((lbt_raw<<6) + (0<<5) + srcSize);
             break;
         case 2: /* 2 - 2 - 12 */
-            ostart[0] = (BYTE)((IS_RAW<<6) + (2<<4) + (srcSize >> 8));
+            ostart[0] = (BYTE)((lbt_raw<<6) + (2<<4) + (srcSize >> 8));
             ostart[1] = (BYTE)srcSize;
             break;
         default:   /*note : should not be necessary : flSize is within {1,2,3} */
         case 3: /* 2 - 2 - 20 */
-            ostart[0] = (BYTE)((IS_RAW<<6) + (3<<4) + (srcSize >> 16));
+            ostart[0] = (BYTE)((lbt_raw<<6) + (3<<4) + (srcSize >> 16));
             ostart[1] = (BYTE)(srcSize>>8);
             ostart[2] = (BYTE)srcSize;
             break;
@@ -603,15 +603,15 @@ static size_t ZSTD_compressRleLiteralsBlock (void* dst, size_t dstCapacity, cons
     switch(flSize)
     {
         case 1: /* 2 - 1 - 5 */
-            ostart[0] = (BYTE)((IS_RLE<<6) + (0<<5) + srcSize);
+            ostart[0] = (BYTE)((lbt_rle<<6) + (0<<5) + srcSize);
             break;
         case 2: /* 2 - 2 - 12 */
-            ostart[0] = (BYTE)((IS_RLE<<6) + (2<<4) + (srcSize >> 8));
+            ostart[0] = (BYTE)((lbt_rle<<6) + (2<<4) + (srcSize >> 8));
             ostart[1] = (BYTE)srcSize;
             break;
         default:   /*note : should not be necessary : flSize is necessarily within {1,2,3} */
         case 3: /* 2 - 2 - 20 */
-            ostart[0] = (BYTE)((IS_RLE<<6) + (3<<4) + (srcSize >> 16));
+            ostart[0] = (BYTE)((lbt_rle<<6) + (3<<4) + (srcSize >> 16));
             ostart[1] = (BYTE)(srcSize>>8);
             ostart[2] = (BYTE)srcSize;
             break;
@@ -632,7 +632,7 @@ static size_t ZSTD_compressLiterals (ZSTD_CCtx* zc,
     size_t const lhSize = 3 + (srcSize >= 1 KB) + (srcSize >= 16 KB);
     BYTE* const ostart = (BYTE*)dst;
     U32 singleStream = srcSize < 256;
-    U32 hType = IS_HUF;
+    litBlockType_t hType = lbt_huffman;
     size_t cLitSize;
 
 
@@ -644,7 +644,7 @@ static size_t ZSTD_compressLiterals (ZSTD_CCtx* zc,
 
     if (dstCapacity < lhSize+1) return ERROR(dstSize_tooSmall);   /* not enough space for compression */
     if (zc->flagStaticTables && (lhSize==3)) {
-        hType = IS_PCH;
+        hType = lbt_repeat;
         singleStream = 1;
         cLitSize = HUF_compress1X_usingCTable(ostart+lhSize, dstCapacity-lhSize, src, srcSize, zc->hufTable);
     } else {

lib/decompress/zstd_decompress.c

@@ -450,13 +450,14 @@ size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
                           const void* src, size_t srcSize)   /* note : srcSize < BLOCKSIZE */
 {
     const BYTE* const istart = (const BYTE*) src;
+    litBlockType_t lbt;
 
-    /* any compressed block with literals segment must be at least this size */
     if (srcSize < MIN_CBLOCK_SIZE) return ERROR(corruption_detected);
+    lbt = (litBlockType_t)(istart[0]>> 6);
 
-    switch(istart[0]>> 6)
+    switch(lbt)
     {
-    case IS_HUF:
+    case lbt_huffman:
         {   size_t litSize, litCSize, singleStream=0;
             U32 lhSize = ((istart[0]) >> 4) & 3;
             if (srcSize < 5) return ERROR(corruption_detected);   /* srcSize >= MIN_CBLOCK_SIZE == 3; here we need up to 5 for lhSize, + cSize (+nbSeq) */
@@ -495,7 +496,7 @@ size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
             dctx->litSize = litSize;
             return litCSize + lhSize;
         }
-    case IS_PCH:
+    case lbt_repeat:
         {   size_t litSize, litCSize;
             U32 lhSize = ((istart[0]) >> 4) & 3;
             if (lhSize != 1)  /* only case supported for now : small litSize, single stream */
@@ -516,7 +517,7 @@ size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
             dctx->litSize = litSize;
             return litCSize + lhSize;
         }
-    case IS_RAW:
+    case lbt_raw:
         {   size_t litSize;
             U32 lhSize = ((istart[0]) >> 4) & 3;
             switch(lhSize)
@@ -547,7 +548,7 @@ size_t ZSTD_decodeLiteralsBlock(ZSTD_DCtx* dctx,
             dctx->litSize = litSize;
             return lhSize+litSize;
         }
-    case IS_RLE:
+    case lbt_rle:
         {   size_t litSize;
             U32 lhSize = ((istart[0]) >> 4) & 3;
             switch(lhSize)
@@ -1317,7 +1318,7 @@ ZSTD_DDict* ZSTD_createDDict_advanced(const void* dict, size_t dictSize, ZSTD_cu
 
 /*! ZSTD_createDDict() :
 *   Create a digested dictionary, ready to start decompression operation without startup delay.
-*   `dict` can be released after creation */
+*   `dict` can be released after `ZSTD_DDict` creation */
 ZSTD_DDict* ZSTD_createDDict(const void* dict, size_t dictSize)
 {
     ZSTD_customMem const allocator = { NULL, NULL, NULL };
@@ -1336,7 +1337,7 @@ size_t ZSTD_freeDDict(ZSTD_DDict* ddict)
 
 /*! ZSTD_decompress_usingDDict() :
 *   Decompression using a pre-digested Dictionary
-*   In contrast with older ZSTD_decompress_usingDict(), use dictionary without significant overhead. */
+*   Use dictionary without significant overhead. */
 ZSTDLIB_API size_t ZSTD_decompress_usingDDict(ZSTD_DCtx* dctx,
                                            void* dst, size_t dstCapacity,
                                      const void* src, size_t srcSize,