--- /dev/null
+/*
+ lz4opt.h - Optimal Mode of LZ4
+ Copyright (C) 2015-2016, Przemyslaw Skibinski <inikep@gmail.com>
+ Note : this file is intended to be included within lz4hc.c
+
+ BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions are
+ met:
+
+ * Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+ * Redistributions in binary form must reproduce the above
+ copyright notice, this list of conditions and the following disclaimer
+ in the documentation and/or other materials provided with the
+ distribution.
+
+ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+ You can contact the author at :
+ - LZ4 source repository : https://github.com/lz4/lz4
+ - LZ4 public forum : https://groups.google.com/forum/#!forum/lz4c
+*/
+
+#define LZ4_LOG_PARSER(fmt, ...) //printf(fmt, __VA_ARGS__)
+#define LZ4_LOG_PRICE(fmt, ...) //printf(fmt, __VA_ARGS__)
+#define LZ4_LOG_ENCODE(fmt, ...) //printf(fmt, __VA_ARGS__)
+
+
+#define LZ4_OPT_NUM (1<<12)
+
+typedef struct
+{
+ int off;
+ int len;
+ int back;
+} LZ4HC_match_t;
+
+typedef struct
+{
+ int price;
+ int off;
+ int mlen;
+ int litlen;
+} LZ4HC_optimal_t;
+
+
+FORCE_INLINE size_t LZ4_LIT_ONLY_COST(size_t litlen)
+{
+ size_t price = 8*litlen;
+ if (litlen>=(int)RUN_MASK) { litlen-=RUN_MASK; price+=8*(1+litlen/255); }
+ return price;
+}
+
+FORCE_INLINE size_t LZ4HC_get_price(size_t litlen, size_t offset, size_t mlen)
+{
+ size_t price = 16 + 8; /* 16-bit offset + token */
+
+ price += 8*litlen;
+ if (litlen>=(int)RUN_MASK) { litlen-=RUN_MASK; price+=8*(1+litlen/255); }
+
+ // mlen-=MINMATCH;
+ if (mlen>=(int)ML_MASK) { mlen-=ML_MASK; price+=8*(1+mlen/255); }
+
+ return price;
+}
+
+
+FORCE_INLINE int LZ4HC_GetAllMatches (
+ LZ4HC_CCtx_internal* ctx,
+ const BYTE* const ip,
+ const BYTE* const iLowLimit,
+ const BYTE* const iHighLimit,
+ size_t best_mlen,
+ LZ4HC_match_t* matches)
+{
+ U16* const chainTable = ctx->chainTable;
+ U32* const HashTable = ctx->hashTable;
+ const BYTE* const base = ctx->base;
+ const U32 dictLimit = ctx->dictLimit;
+ const BYTE* const lowPrefixPtr = base + dictLimit;
+ const U32 current = (U32)(ip - base);
+ const U32 lowLimit = (ctx->lowLimit + MAX_DISTANCE > current) ? ctx->lowLimit : current - (MAX_DISTANCE - 1);
+ const BYTE* const dictBase = ctx->dictBase;
+ const BYTE* match;
+ U32 matchIndex;
+ int nbAttempts = ctx->searchNum;
+ int mnum = 0;
+ U32* HashPos;
+
+ if (ip + MINMATCH > iHighLimit) return 0;
+
+ /* First Match */
+ HashPos = &HashTable[LZ4HC_hashPtr(ip)];
+ matchIndex = *HashPos;
+
+
+ DELTANEXTU16(current) = (U16)(current - matchIndex);
+ *HashPos = current;
+ ctx->nextToUpdate++;
+
+
+ while ((matchIndex < current) && (matchIndex>=lowLimit) && (nbAttempts))
+ {
+ nbAttempts--;
+ if (matchIndex >= dictLimit)
+ {
+ match = base + matchIndex;
+
+ if ((ip[best_mlen] == match[best_mlen]) && (LZ4_read32(match) == LZ4_read32(ip)))
+ {
+ size_t mlt = MINMATCH + LZ4_count(ip+MINMATCH, match+MINMATCH, iHighLimit);
+ int back = 0;
+
+ while ((ip+back>iLowLimit)
+ && (match+back > lowPrefixPtr)
+ && (ip[back-1] == match[back-1]))
+ back--;
+
+ mlt -= back;
+
+ if (mlt > best_mlen)
+ {
+ best_mlen = mlt;
+ matches[mnum].off = (int)(ip - match);
+ matches[mnum].len = (int)mlt;
+ matches[mnum].back = -back;
+ mnum++;
+ }
+
+ if (best_mlen > LZ4_OPT_NUM) break;
+ }
+ }
+ else
+ {
+ match = dictBase + matchIndex;
+ if (LZ4_read32(match) == LZ4_read32(ip))
+ {
+ size_t mlt;
+ int back=0;
+ const BYTE* vLimit = ip + (dictLimit - matchIndex);
+ if (vLimit > iHighLimit) vLimit = iHighLimit;
+ mlt = LZ4_count(ip+MINMATCH, match+MINMATCH, vLimit) + MINMATCH;
+ if ((ip+mlt == vLimit) && (vLimit < iHighLimit))
+ mlt += LZ4_count(ip+mlt, base+dictLimit, iHighLimit);
+ while ((ip+back > iLowLimit) && (matchIndex+back > lowLimit) && (ip[back-1] == match[back-1])) back--;
+ mlt -= back;
+
+ if (mlt > best_mlen)
+ {
+ best_mlen = mlt;
+ matches[mnum].off = (int)(ip - match);
+ matches[mnum].len = (int)mlt;
+ matches[mnum].back = -back;
+ mnum++;
+ }
+
+ if (best_mlen > LZ4_OPT_NUM) break;
+ }
+ }
+ matchIndex -= DELTANEXTU16(matchIndex);
+ }
+
+
+ return mnum;
+}
+
+
+
+FORCE_INLINE int LZ4HC_BinTree_GetAllMatches (
+ LZ4HC_CCtx_internal* ctx,
+ const BYTE* const ip,
+ const BYTE* const iHighLimit,
+ size_t best_mlen,
+ LZ4HC_match_t* matches)
+{
+ U16* const chainTable = ctx->chainTable;
+ U32* const HashTable = ctx->hashTable;
+ const BYTE* const base = ctx->base;
+ const U32 dictLimit = ctx->dictLimit;
+ const U32 current = (U32)(ip - base);
+ const U32 lowLimit = (ctx->lowLimit + MAX_DISTANCE > current) ? ctx->lowLimit : current - (MAX_DISTANCE - 1);
+ const BYTE* const dictBase = ctx->dictBase;
+ const BYTE* match;
+ int nbAttempts = ctx->searchNum;
+ int mnum = 0;
+ U16 *ptr0, *ptr1;
+ U32 matchIndex, delta0, delta1;
+ size_t mlt = 0;
+ U32* HashPos;
+
+ if (ip + MINMATCH > iHighLimit) return 0;
+
+ /* First Match */
+ HashPos = &HashTable[LZ4HC_hashPtr(ip)];
+ matchIndex = *HashPos;
+
+ *HashPos = current;
+ ctx->nextToUpdate++;
+
+ // check rest of matches
+ ptr0 = &DELTANEXTU16(current*2+1);
+ ptr1 = &DELTANEXTU16(current*2);
+ delta0 = delta1 = current - matchIndex;
+
+ while ((matchIndex < current) && (matchIndex>=lowLimit) && (nbAttempts))
+ {
+ nbAttempts--;
+ mlt = 0;
+ if (matchIndex >= dictLimit)
+ {
+ match = base + matchIndex;
+
+ if (LZ4_read32(match) == LZ4_read32(ip))
+ {
+ mlt = MINMATCH + LZ4_count(ip+MINMATCH, match+MINMATCH, iHighLimit);
+
+ if (mlt > best_mlen)
+ {
+ best_mlen = mlt;
+ matches[mnum].off = (int)(ip - match);
+ matches[mnum].len = (int)mlt;
+ matches[mnum].back = 0;
+ mnum++;
+ }
+
+ if (best_mlen > LZ4_OPT_NUM) break;
+ }
+ }
+ else
+ {
+ match = dictBase + matchIndex;
+ if (LZ4_read32(match) == LZ4_read32(ip))
+ {
+ const BYTE* vLimit = ip + (dictLimit - matchIndex);
+ if (vLimit > iHighLimit) vLimit = iHighLimit;
+ mlt = LZ4_count(ip+MINMATCH, match+MINMATCH, vLimit) + MINMATCH;
+ if ((ip+mlt == vLimit) && (vLimit < iHighLimit))
+ mlt += LZ4_count(ip+mlt, base+dictLimit, iHighLimit);
+
+ if (mlt > best_mlen)
+ {
+ best_mlen = mlt;
+ matches[mnum].off = (int)(ip - match);
+ matches[mnum].len = (int)mlt;
+ matches[mnum].back = 0;
+ mnum++;
+ }
+
+ if (best_mlen > LZ4_OPT_NUM) break;
+ }
+ }
+
+ if (*(ip+mlt) < *(match+mlt))
+ {
+ *ptr0 = delta0;
+ ptr0 = &DELTANEXTU16(matchIndex*2);
+ // printf("delta0=%d\n", delta0);
+ if (*ptr0 == (U16)-1) break;
+ delta0 = *ptr0;
+ delta1 += delta0;
+ matchIndex -= delta0;
+ }
+ else
+ {
+ *ptr1 = delta1;
+ ptr1 = &DELTANEXTU16(matchIndex*2+1);
+ // printf("delta1=%d\n", delta1);
+ if (*ptr1 == (U16)-1) break;
+ delta1 = *ptr1;
+ delta0 += delta1;
+ matchIndex -= delta1;
+ }
+ }
+
+ *ptr0 = (U16)-1;
+ *ptr1 = (U16)-1;
+
+ return mnum;
+}
+
+
+
+
+
+#define SET_PRICE(pos, mlen, offset, litlen, price) \
+ { \
+ while (last_pos < pos) { opt[last_pos+1].price = 1<<30; last_pos++; } \
+ opt[pos].mlen = (int)mlen; \
+ opt[pos].off = (int)offset; \
+ opt[pos].litlen = (int)litlen; \
+ opt[pos].price = (int)price; \
+ LZ4_LOG_PARSER("%d: SET price[%d/%d]=%d litlen=%d len=%d off=%d\n", (int)(inr-source), pos, last_pos, opt[pos].price, opt[pos].litlen, opt[pos].mlen, opt[pos].off); \
+ }
+
+
+static int LZ4HC_compress_optimal (
+ LZ4HC_CCtx_internal* ctx,
+ const BYTE* source,
+ char* dest,
+ int inputSize,
+ int maxOutputSize,
+ limitedOutput_directive limit,
+ const int binaryTreeFinder,
+ const size_t sufficient_len,
+ const int faster_get_matches
+ )
+{
+ LZ4HC_optimal_t opt[LZ4_OPT_NUM + 4];
+ LZ4HC_match_t matches[LZ4_OPT_NUM + 1];
+ const BYTE *inr;
+ size_t res, cur, cur2, skip_num = 0;
+ size_t i, llen, litlen, mlen, best_mlen, price, offset, best_off, match_num, last_pos;
+
+ const BYTE* ip = (const BYTE*) source;
+ const BYTE* anchor = ip;
+ const BYTE* const iend = ip + inputSize;
+ const BYTE* const mflimit = iend - MFLIMIT;
+ const BYTE* const matchlimit = (iend - LASTLITERALS);
+ BYTE* op = (BYTE*) dest;
+ BYTE* const oend = op + maxOutputSize;
+
+
+ /* init */
+ ctx->end += inputSize;
+ ip++;
+
+ /* Main Loop */
+ while (ip < mflimit)
+ {
+ memset(opt, 0, sizeof(LZ4HC_optimal_t));
+ last_pos = 0;
+ llen = ip - anchor;
+
+ best_mlen = (last_pos) ? last_pos : (MINMATCH-1);
+
+ if (faster_get_matches && last_pos)
+ match_num = 0;
+ else
+ {
+ if (!binaryTreeFinder)
+ {
+ LZ4HC_Insert(ctx, ip);
+ match_num = LZ4HC_GetAllMatches(ctx, ip, ip, matchlimit, best_mlen, matches);
+ }
+ else
+ {
+ match_num = LZ4HC_BinTree_GetAllMatches(ctx, ip, matchlimit, best_mlen, matches);
+ }
+ }
+
+ LZ4_LOG_PARSER("%d: match_num=%d last_pos=%d\n", (int)(ip-source), match_num, last_pos);
+ if (!last_pos && !match_num) { ip++; continue; }
+
+ if (match_num && (size_t)matches[match_num-1].len > sufficient_len)
+ {
+ best_mlen = matches[match_num-1].len;
+ best_off = matches[match_num-1].off;
+ cur = 0;
+ last_pos = 1;
+ goto encode;
+ }
+
+ // set prices using matches at position = 0
+ for (i = 0; i < match_num; i++)
+ {
+ mlen = (i>0) ? (size_t)matches[i-1].len+1 : best_mlen;
+ best_mlen = (matches[i].len < LZ4_OPT_NUM) ? matches[i].len : LZ4_OPT_NUM;
+ LZ4_LOG_PARSER("%d: start Found mlen=%d off=%d best_mlen=%d last_pos=%d\n", (int)(ip-source), matches[i].len, matches[i].off, best_mlen, last_pos);
+ while (mlen <= best_mlen)
+ {
+ litlen = 0;
+ price = LZ4HC_get_price(llen + litlen, matches[i].off, mlen - MINMATCH) - llen;
+ if (mlen > last_pos || price < (size_t)opt[mlen].price)
+ SET_PRICE(mlen, mlen, matches[i].off, litlen, price);
+ mlen++;
+ }
+ }
+
+ if (last_pos < MINMATCH) { ip++; continue; }
+
+ opt[0].mlen = opt[1].mlen = 1;
+
+ // check further positions
+ for (skip_num = 0, cur = 1; cur <= last_pos; cur++)
+ {
+ inr = ip + cur;
+
+ if (opt[cur-1].mlen == 1)
+ {
+ litlen = opt[cur-1].litlen + 1;
+
+ if (cur != litlen)
+ {
+ price = opt[cur - litlen].price + LZ4_LIT_ONLY_COST(litlen);
+ LZ4_LOG_PRICE("%d: TRY1 opt[%d].price=%d price=%d cur=%d litlen=%d\n", (int)(inr-source), cur - litlen, opt[cur - litlen].price, price, cur, litlen);
+ }
+ else
+ {
+ price = LZ4_LIT_ONLY_COST(llen + litlen) - llen;
+ LZ4_LOG_PRICE("%d: TRY2 price=%d cur=%d litlen=%d llen=%d\n", (int)(inr-source), price, cur, litlen, llen);
+ }
+ }
+ else
+ {
+ litlen = 1;
+ price = opt[cur - 1].price + LZ4_LIT_ONLY_COST(litlen);
+ LZ4_LOG_PRICE("%d: TRY3 price=%d cur=%d litlen=%d litonly=%d\n", (int)(inr-source), price, cur, litlen, LZ4_LIT_ONLY_COST(litlen));
+ }
+
+ mlen = 1;
+ best_mlen = 0;
+ LZ4_LOG_PARSER("%d: TRY price=%d opt[%d].price=%d\n", (int)(inr-source), price, cur, opt[cur].price);
+
+ if (cur > last_pos || price <= (size_t)opt[cur].price) // || ((price == opt[cur].price) && (opt[cur-1].mlen == 1) && (cur != litlen)))
+ SET_PRICE(cur, mlen, best_mlen, litlen, price);
+
+ if (cur == last_pos) break;
+
+ LZ4_LOG_PARSER("%d: CURRENT price[%d/%d]=%d off=%d mlen=%d litlen=%d\n", (int)(inr-source), cur, last_pos, opt[cur].price, opt[cur].off, opt[cur].mlen, opt[cur].litlen);
+
+
+ if (faster_get_matches && skip_num > 0)
+ {
+ skip_num--;
+ continue;
+ }
+
+
+ best_mlen = (best_mlen > MINMATCH) ? best_mlen : (MINMATCH-1);
+
+ if (!binaryTreeFinder)
+ {
+ LZ4HC_Insert(ctx, inr);
+ match_num = LZ4HC_GetAllMatches(ctx, inr, ip, matchlimit, best_mlen, matches);
+ LZ4_LOG_PARSER("%d: LZ4HC_GetAllMatches match_num=%d\n", (int)(inr-source), match_num);
+ }
+ else
+ {
+ match_num = LZ4HC_BinTree_GetAllMatches(ctx, inr, matchlimit, best_mlen, matches);
+ LZ4_LOG_PARSER("%d: LZ4HC_BinTree_GetAllMatches match_num=%d\n", (int)(inr-source), match_num);
+ }
+
+
+ if (match_num > 0 && (size_t)matches[match_num-1].len > sufficient_len)
+ {
+ cur -= matches[match_num-1].back;
+ best_mlen = matches[match_num-1].len;
+ best_off = matches[match_num-1].off;
+ last_pos = cur + 1;
+ goto encode;
+ }
+
+ // set prices using matches at position = cur
+ for (i = 0; i < match_num; i++)
+ {
+ mlen = (i>0) ? (size_t)matches[i-1].len+1 : best_mlen;
+ cur2 = cur - matches[i].back;
+ best_mlen = (cur2 + matches[i].len < LZ4_OPT_NUM) ? (size_t)matches[i].len : LZ4_OPT_NUM - cur2;
+ LZ4_LOG_PARSER("%d: Found1 cur=%d cur2=%d mlen=%d off=%d best_mlen=%d last_pos=%d\n", (int)(inr-source), cur, cur2, matches[i].len, matches[i].off, best_mlen, last_pos);
+
+ if (mlen < (size_t)matches[i].back + 1)
+ mlen = matches[i].back + 1;
+
+ while (mlen <= best_mlen)
+ {
+ if (opt[cur2].mlen == 1)
+ {
+ litlen = opt[cur2].litlen;
+
+ if (cur2 != litlen)
+ price = opt[cur2 - litlen].price + LZ4HC_get_price(litlen, matches[i].off, mlen - MINMATCH);
+ else
+ price = LZ4HC_get_price(llen + litlen, matches[i].off, mlen - MINMATCH) - llen;
+ }
+ else
+ {
+ litlen = 0;
+ price = opt[cur2].price + LZ4HC_get_price(litlen, matches[i].off, mlen - MINMATCH);
+ }
+
+ LZ4_LOG_PARSER("%d: Found2 pred=%d mlen=%d best_mlen=%d off=%d price=%d litlen=%d price[%d]=%d\n", (int)(inr-source), matches[i].back, mlen, best_mlen, matches[i].off, price, litlen, cur - litlen, opt[cur - litlen].price);
+ // if (cur2 + mlen > last_pos || ((matches[i].off != opt[cur2 + mlen].off) && (price < opt[cur2 + mlen].price)))
+ if (cur2 + mlen > last_pos || price < (size_t)opt[cur2 + mlen].price)
+ {
+ SET_PRICE(cur2 + mlen, mlen, matches[i].off, litlen, price);
+ }
+
+ mlen++;
+ }
+ }
+ } // for (skip_num = 0, cur = 1; cur <= last_pos; cur++)
+
+
+ best_mlen = opt[last_pos].mlen;
+ best_off = opt[last_pos].off;
+ cur = last_pos - best_mlen;
+
+encode: // cur, last_pos, best_mlen, best_off have to be set
+ for (i = 1; i <= last_pos; i++)
+ {
+ LZ4_LOG_PARSER("%d: price[%d/%d]=%d off=%d mlen=%d litlen=%d\n", (int)(ip-source+i), i, last_pos, opt[i].price, opt[i].off, opt[i].mlen, opt[i].litlen);
+ }
+
+ LZ4_LOG_PARSER("%d: cur=%d/%d best_mlen=%d best_off=%d\n", (int)(ip-source+cur), cur, last_pos, best_mlen, best_off);
+
+ opt[0].mlen = 1;
+
+ while (1)
+ {
+ mlen = opt[cur].mlen;
+ offset = opt[cur].off;
+ opt[cur].mlen = (int)best_mlen;
+ opt[cur].off = (int)best_off;
+ best_mlen = mlen;
+ best_off = offset;
+ if (mlen > cur) break;
+ cur -= mlen;
+ }
+
+ for (i = 0; i <= last_pos;)
+ {
+ LZ4_LOG_PARSER("%d: price2[%d/%d]=%d off=%d mlen=%d litlen=%d\n", (int)(ip-source+i), i, last_pos, opt[i].price, opt[i].off, opt[i].mlen, opt[i].litlen);
+ i += opt[i].mlen;
+ }
+
+ cur = 0;
+
+ while (cur < last_pos)
+ {
+ LZ4_LOG_PARSER("%d: price3[%d/%d]=%d off=%d mlen=%d litlen=%d\n", (int)(ip-source+cur), cur, last_pos, opt[cur].price, opt[cur].off, opt[cur].mlen, opt[cur].litlen);
+ mlen = opt[cur].mlen;
+ if (mlen == 1) { ip++; cur++; continue; }
+ offset = opt[cur].off;
+ cur += mlen;
+
+ LZ4_LOG_ENCODE("%d: ENCODE literals=%d off=%d mlen=%d ", (int)(ip-source), (int)(ip-anchor), (int)(offset), mlen);
+ res = LZ4HC_encodeSequence(&ip, &op, &anchor, (int)mlen, ip - offset, limit, oend);
+ LZ4_LOG_ENCODE("out=%d\n", (int)((char*)op - dest));
+
+ if (res) return 0;
+
+ LZ4_LOG_PARSER("%d: offset=%d\n", (int)(ip-source), offset);
+ }
+ }
+
+ /* Encode Last Literals */
+ {
+ int lastRun = (int)(iend - anchor);
+ // if (inputSize > LASTLITERALS && lastRun < LASTLITERALS) { printf("ERROR: lastRun=%d\n", lastRun); }
+ if ((limit) && (((char*)op - dest) + lastRun + 1 + ((lastRun+255-RUN_MASK)/255) > (U32)maxOutputSize)) return 0; /* Check output limit */
+ if (lastRun>=(int)RUN_MASK) { *op++=(RUN_MASK<<ML_BITS); lastRun-=RUN_MASK; for(; lastRun > 254 ; lastRun-=255) *op++ = 255; *op++ = (BYTE) lastRun; }
+ else *op++ = (BYTE)(lastRun<<ML_BITS);
+ LZ4_LOG_ENCODE("%d: ENCODE_LAST literals=%d out=%d\n", (int)(ip-source), (int)(iend-anchor), (int)((char*)op -dest));
+ memcpy(op, anchor, iend - anchor);
+ op += iend-anchor;
+ }
+
+ /* End */
+ return (int) ((char*)op-dest);
+}
+
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