Merge remote-tracking branch 'upstream/dev' into fixes

* upstream/dev:
  added doc\zstd_manual.html
  added contrib\gen_html
  zstd_compression_format.md moved to doc/
  Fix small bug in ZSTD_execSequence()
  improved ZSTD_compressBlock_opt_extDict_generic
  protect ZSTD_decodeFrameHeader() from invalid usage, as suggested by @spaskob
  zstd_opt.h: small improvement in compression ratio
  improved dicitonary segment merge
  use implicit rules to compile zstd_decompress.c
  detect early impossible decompression scenario in legacy decoder v0.5
  no repeat mode in legacy v0.5
  fixed invalid invocation of dictionary in legacy decoder v0.5
  fix edge case
  fix command line interpretation
  fixed minor corner case
  zstd.h: added the Introduction section
  fixed clang 3.5 warnings
  zstd.h: updated comments

lib/legacy/zstd_v04.c

@@ -3111,7 +3111,7 @@ static size_t ZSTD_execSequence(BYTE* op,
             sequence.matchLength -= length1;
             match = base;
             if (op > oend_8) {
-              memmove(op, match, sequence.matchLength);
+              while (op < oMatchEnd) *op++ = *match++;
               return sequenceLength;
             }
         }

lib/legacy/zstd_v05.c

@@ -2035,13 +2035,14 @@ size_t HUFv05_decompress1X2_usingDTable(
 {
     BYTE* op = (BYTE*)dst;
     BYTE* const oend = op + dstSize;
-    size_t errorCode;
     const U32 dtLog = DTable[0];
     const void* dtPtr = DTable;
     const HUFv05_DEltX2* const dt = ((const HUFv05_DEltX2*)dtPtr)+1;
     BITv05_DStream_t bitD;
-    errorCode = BITv05_initDStream(&bitD, cSrc, cSrcSize);
-    if (HUFv05_isError(errorCode)) return errorCode;
+
+    if (dstSize <= cSrcSize) return ERROR(dstSize_tooSmall);
+    { size_t const errorCode = BITv05_initDStream(&bitD, cSrc, cSrcSize);
+      if (HUFv05_isError(errorCode)) return errorCode; }
 
     HUFv05_decodeStreamX2(op, &bitD, oend, dt, dtLog);
 
@@ -3070,7 +3071,7 @@ size_t ZSTDv05_decodeLiteralsBlock(ZSTDv05_DCtx* dctx,
 
 size_t ZSTDv05_decodeSeqHeaders(int* nbSeq, const BYTE** dumpsPtr, size_t* dumpsLengthPtr,
                          FSEv05_DTable* DTableLL, FSEv05_DTable* DTableML, FSEv05_DTable* DTableOffb,
-                         const void* src, size_t srcSize)
+                         const void* src, size_t srcSize, U32 flagStaticTable)
 {
     const BYTE* const istart = (const BYTE* const)src;
     const BYTE* ip = istart;
@@ -3130,6 +3131,7 @@ size_t ZSTDv05_decodeSeqHeaders(int* nbSeq, const BYTE** dumpsPtr, size_t* dumps
             FSEv05_buildDTable_raw(DTableLL, LLbits);
             break;
         case FSEv05_ENCODING_STATIC:
+            if (!flagStaticTable) return ERROR(corruption_detected);
             break;
         case FSEv05_ENCODING_DYNAMIC :
         default :   /* impossible */
@@ -3153,6 +3155,7 @@ size_t ZSTDv05_decodeSeqHeaders(int* nbSeq, const BYTE** dumpsPtr, size_t* dumps
             FSEv05_buildDTable_raw(DTableOffb, Offbits);
             break;
         case FSEv05_ENCODING_STATIC:
+            if (!flagStaticTable) return ERROR(corruption_detected);
             break;
         case FSEv05_ENCODING_DYNAMIC :
         default :   /* impossible */
@@ -3176,6 +3179,7 @@ size_t ZSTDv05_decodeSeqHeaders(int* nbSeq, const BYTE** dumpsPtr, size_t* dumps
             FSEv05_buildDTable_raw(DTableML, MLbits);
             break;
         case FSEv05_ENCODING_STATIC:
+            if (!flagStaticTable) return ERROR(corruption_detected);
             break;
         case FSEv05_ENCODING_DYNAMIC :
         default :   /* impossible */
@@ -3325,7 +3329,7 @@ static size_t ZSTDv05_execSequence(BYTE* op,
             sequence.matchLength -= length1;
             match = base;
             if (op > oend_8) {
-              memmove(op, match, sequence.matchLength);
+              while (op < oMatchEnd) *op++ = *match++;
               return sequenceLength;
             }
     }   }
@@ -3388,7 +3392,7 @@ static size_t ZSTDv05_decompressSequences(
     /* Build Decoding Tables */
     errorCode = ZSTDv05_decodeSeqHeaders(&nbSeq, &dumps, &dumpsLength,
                                       DTableLL, DTableML, DTableOffb,
-                                      ip, seqSize);
+                                      ip, seqSize, dctx->flagStaticTables);
     if (ZSTDv05_isError(errorCode)) return errorCode;
     ip += errorCode;
 

lib/legacy/zstd_v06.c

@@ -3474,7 +3474,7 @@ size_t ZSTDv06_execSequence(BYTE* op,
             sequence.matchLength -= length1;
             match = base;
             if (op > oend_8) {
-              memmove(op, match, sequence.matchLength);
+              while (op < oMatchEnd) *op++ = *match++;
               return sequenceLength;
             }
     }   }

lib/legacy/zstd_v07.c

@@ -3697,7 +3697,7 @@ size_t ZSTDv07_execSequence(BYTE* op,
             sequence.matchLength -= length1;
             match = base;
             if (op > oend_w) {
-              memmove(op, match, sequence.matchLength);
+              while (op < oMatchEnd) *op++ = *match++;
               return sequenceLength;
             }
     }   }