-#include <stdlib.h>
-#include <string.h>
+#include <limits.h>
#include <stdint.h>
#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
#include "ldm.h"
// Insert every (HASH_ONLY_EVERY + 1) into the hash table.
#define HASH_ONLY_EVERY 0
-#define LDM_MEMORY_USAGE 22
-#define LDM_HASHLOG (LDM_MEMORY_USAGE-2)
-#define LDM_HASHTABLESIZE (1 << (LDM_MEMORY_USAGE))
-#define LDM_HASHTABLESIZE_U32 ((LDM_HASHTABLESIZE) >> 2)
-
-#define LDM_OFFSET_SIZE 4
-
-#define WINDOW_SIZE (1 << 29)
-
-//These should be multiples of four.
-#define LDM_HASH_LENGTH 8
-
#define ML_BITS 4
#define ML_MASK ((1U<<ML_BITS)-1)
#define RUN_BITS (8-ML_BITS)
offset_t offset;
};
+// TODO: Add offset histogram by powers of two
+// TODO: Scanning speed
+// TODO: Memory usage
struct LDM_compressStats {
U32 numMatches;
- U32 totalMatchLength;
- U32 totalLiteralLength;
+ U64 totalMatchLength;
+ U64 totalLiteralLength;
U64 totalOffset;
+ U32 minOffset, maxOffset;
+
U32 numCollisions;
U32 numHashInserts;
};
struct LDM_CCtx {
- size_t isize; /* Input size */
- size_t maxOSize; /* Maximum output size */
+ U64 isize; /* Input size */
+ U64 maxOSize; /* Maximum output size */
const BYTE *ibase; /* Base of input */
const BYTE *ip; /* Current input position */
const BYTE *DEBUG_setNextHash;
};
-void LDM_printCompressStats(const LDM_compressStats *stats,
- const LDM_hashEntry *hashTable,
- U32 hashTableSize) {
+void LDM_outputHashtableOccupancy(
+ const LDM_hashEntry *hashTable, U32 hashTableSize) {
+ U32 i = 0;
+ U32 ctr = 0;
+ for (; i < hashTableSize; i++) {
+ if (hashTable[i].offset == 0) {
+ ctr++;
+ }
+ }
+ printf("Hash table size, empty slots, %% empty: %u, %u, %.3f\n",
+ hashTableSize, ctr,
+ 100.0 * (double)(ctr) / (double)hashTableSize);
+}
+
+void LDM_printCompressStats(const LDM_compressStats *stats) {
printf("=====================\n");
printf("Compression statistics\n");
- printf("Total number of matches: %u\n", stats->numMatches);
- printf("Average match length: %.1f\n", ((double)stats->totalMatchLength) /
+ //TODO: compute percentage matched?
+ printf("num matches, total match length: %u, %llu\n",
+ stats->numMatches,
+ stats->totalMatchLength);
+ printf("avg match length: %.1f\n", ((double)stats->totalMatchLength) /
(double)stats->numMatches);
- printf("Average literal length: %.1f\n",
+ printf("avg literal length: %.1f\n",
((double)stats->totalLiteralLength) / (double)stats->numMatches);
- printf("Average offset length: %.1f\n",
+ printf("avg offset length: %.1f\n",
((double)stats->totalOffset) / (double)stats->numMatches);
- printf("Num collisions, num hash inserts, %% collisions: %u, %u, %.3f\n",
+ printf("min offset, max offset: %u %u\n",
+ stats->minOffset, stats->maxOffset);
+ printf("num collisions, num hash inserts, %% collisions: %u, %u, %.3f\n",
stats->numCollisions, stats->numHashInserts,
stats->numHashInserts == 0 ?
1.0 : (100.0 * (double)stats->numCollisions) /
(double)stats->numHashInserts);
-
- // Output occupancy of hash table.
- {
- U32 i = 0;
- U32 ctr = 0;
- for (; i < hashTableSize; i++) {
- if (hashTable[i].offset == 0) {
- ctr++;
- }
- }
- printf("Hash table size, empty slots, %% empty: %u %u %.3f\n",
- hashTableSize, ctr,
- 100.0 * (double)(ctr) / (double)hashTableSize);
- }
-
- printf("=====================\n");
}
int LDM_isValidMatch(const BYTE *pIn, const BYTE *pMatch) {
// cctx->nextSum = getChecksum((const char *)cctx->nextIp, LDM_HASH_LENGTH);
cctx->nextSum = updateChecksum(
cctx->lastSum, LDM_HASH_LENGTH,
- (cctx->lastPosHashed)[0],
- (cctx->lastPosHashed)[LDM_HASH_LENGTH]);
+ cctx->lastPosHashed[0],
+ cctx->lastPosHashed[LDM_HASH_LENGTH]);
cctx->nextPosHashed = cctx->nextIp;
cctx->nextHash = checksumToHash(cctx->nextSum);
LDM_CCtx *cctx, hash_t hash, U32 sum) {
#ifdef COMPUTE_STATS
if (cctx->stats.numHashInserts < LDM_HASHTABLESIZE_U32) {
- offset_t offset = (cctx->hashTable)[hash].offset;
+ offset_t offset = cctx->hashTable[hash].offset;
cctx->stats.numHashInserts++;
if (offset != 0 && !LDM_isValidMatch(cctx->ip, offset + cctx->ibase)) {
cctx->stats.numCollisions++;
// Hash only every HASH_ONLY_EVERY times, based on cctx->ip.
// Note: this works only when cctx->step is 1.
if (((cctx->ip - cctx->ibase) & HASH_ONLY_EVERY) == HASH_ONLY_EVERY) {
- (cctx->hashTable)[hash] =
- (LDM_hashEntry){ (offset_t)(cctx->ip - cctx->ibase) };
+ const LDM_hashEntry entry = { cctx->ip - cctx->ibase };
+ cctx->hashTable[hash] = entry;
}
cctx->lastPosHashed = cctx->ip;
memset(&(cctx->stats), 0, sizeof(cctx->stats));
memset(cctx->hashTable, 0, sizeof(cctx->hashTable));
+ cctx->stats.minOffset = UINT_MAX;
cctx->lastPosHashed = NULL;
cctx.stats.totalLiteralLength += literalLength;
cctx.stats.totalOffset += offset;
cctx.stats.totalMatchLength += matchLength + LDM_MIN_MATCH_LENGTH;
+ cctx.stats.minOffset =
+ offset < cctx.stats.minOffset ? offset : cctx.stats.minOffset;
+ cctx.stats.maxOffset =
+ offset > cctx.stats.maxOffset ? offset : cctx.stats.maxOffset;
#endif
LDM_outputBlock(&cctx, literalLength, offset, matchLength);
}
#ifdef COMPUTE_STATS
- LDM_printCompressStats(&cctx.stats, cctx.hashTable, LDM_HASHTABLESIZE_U32);
+ LDM_printCompressStats(&cctx.stats);
+ LDM_outputHashtableOccupancy(cctx.hashTable, LDM_HASHTABLESIZE_U32);
#endif
return (cctx.op - (const BYTE *)cctx.obase);
#define LDM_COMPRESS_SIZE 8
#define LDM_DECOMPRESS_SIZE 8
#define LDM_HEADER_SIZE ((LDM_COMPRESS_SIZE)+(LDM_DECOMPRESS_SIZE))
+#define LDM_OFFSET_SIZE 4
-// This should be a multiple of four.
+// Defines the size of the hash table.
+#define LDM_MEMORY_USAGE 22
+#define LDM_HASHLOG (LDM_MEMORY_USAGE-2)
+#define LDM_HASHTABLESIZE (1 << (LDM_MEMORY_USAGE))
+#define LDM_HASHTABLESIZE_U32 ((LDM_HASHTABLESIZE) >> 2)
+
+#define WINDOW_SIZE (1 << 25)
+
+//These should be multiples of four.
#define LDM_MIN_MATCH_LENGTH 8
+#define LDM_HASH_LENGTH 8
typedef U32 offset_t;
typedef U32 hash_t;
void LDM_initializeCCtx(LDM_CCtx *cctx,
const void *src, size_t srcSize,
void *dst, size_t maxDstSize);
+
+/**
+ * Prints the percentage of the hash table occupied (where occupied is defined
+ * as the entry being non-zero).
+ */
+void LDM_outputHashtableOccupancy(const LDM_hashEntry *hashTable,
+ U32 hashTableSize);
+
/**
* Outputs compression statistics to stdout.
*/
-void LDM_printCompressStats(const LDM_compressStats *stats,
- const LDM_hashEntry *hashTable,
- U32 hashTableSize);
+void LDM_printCompressStats(const LDM_compressStats *stats);
/**
* Checks whether the LDM_MIN_MATCH_LENGTH bytes from p are the same as the
* LDM_MIN_MATCH_LENGTH bytes from match.
+# ################################################################
+# Copyright (c) 2016-present, Yann Collet, Facebook, Inc.
+# All rights reserved.
+#
+# This source code is licensed under the BSD-style license found in the
+# LICENSE file in the root directory of this source tree. An additional grant
+# of patent rights can be found in the PATENTS file in the same directory.
+# ################################################################
+
# This Makefile presumes libzstd is installed, using `sudo make install`
+CPPFLAGS+= -I../../../../lib/common
CFLAGS ?= -O3
DEBUGFLAGS = -Wall -Wextra -Wcast-qual -Wcast-align -Wshadow \
-Wstrict-aliasing=1 -Wswitch-enum -Wdeclaration-after-statement \
all: main-ldm
-main-ldm : util.c ldm.c main-ldm.c
+main-ldm : ldm.c main-ldm.c
$(CC) $(CPPFLAGS) $(CFLAGS) $^ $(LDFLAGS) -o $@
clean:
@rm -f core *.o tmp* result* *.ldm *.ldm.dec \
- main-ldm
+ main main-ldm
@echo Cleaning completed
-#include <stdlib.h>
-#include <string.h>
+#include <limits.h>
#include <stdint.h>
#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
#include "ldm.h"
-#include "util.h"
// Insert every (HASH_ONLY_EVERY + 1) into the hash table.
#define HASH_ONLY_EVERY 0
-#define LDM_MEMORY_USAGE 20
-#define LDM_HASHLOG (LDM_MEMORY_USAGE-2)
-#define LDM_HASHTABLESIZE (1 << (LDM_MEMORY_USAGE))
-#define LDM_HASHTABLESIZE_U32 ((LDM_HASHTABLESIZE) >> 2)
-
-#define LDM_OFFSET_SIZE 4
-
-#define WINDOW_SIZE (1 << 20)
-
-//These should be multiples of four.
-#define LDM_HASH_LENGTH 4
-#define MINMATCH 4
-
#define ML_BITS 4
#define ML_MASK ((1U<<ML_BITS)-1)
#define RUN_BITS (8-ML_BITS)
#define RUN_MASK ((1U<<RUN_BITS)-1)
#define COMPUTE_STATS
+#define CHECKSUM_CHAR_OFFSET 0
//#define RUN_CHECKS
//#define LDM_DEBUG
-typedef uint8_t BYTE;
-typedef uint16_t U16;
-typedef uint32_t U32;
-typedef int32_t S32;
-typedef uint64_t U64;
-
-typedef uint32_t offset_t;
-typedef uint32_t hash_t;
-typedef signed char schar;
-
-typedef struct hashEntry {
+struct LDM_hashEntry {
offset_t offset;
-} hashEntry;
+};
-typedef struct LDM_compressStats {
+// TODO: Add offset histogram by powers of two
+// TODO: Scanning speed
+// TODO: Memory usage
+struct LDM_compressStats {
U32 numMatches;
- U32 totalMatchLength;
- U32 totalLiteralLength;
+ U64 totalMatchLength;
+ U64 totalLiteralLength;
U64 totalOffset;
+ U32 minOffset, maxOffset;
+
U32 numCollisions;
U32 numHashInserts;
-} LDM_compressStats;
+};
-typedef struct LDM_CCtx {
- size_t isize; /* Input size */
- size_t maxOSize; /* Maximum output size */
+struct LDM_CCtx {
+ U64 isize; /* Input size */
+ U64 maxOSize; /* Maximum output size */
const BYTE *ibase; /* Base of input */
const BYTE *ip; /* Current input position */
LDM_compressStats stats; /* Compression statistics */
- hashEntry hashTable[LDM_HASHTABLESIZE_U32];
+ LDM_hashEntry hashTable[LDM_HASHTABLESIZE_U32];
const BYTE *lastPosHashed; /* Last position hashed */
hash_t lastHash; /* Hash corresponding to lastPosHashed */
// DEBUG
const BYTE *DEBUG_setNextHash;
-} LDM_CCtx;
+};
+
+void LDM_outputHashtableOccupancy(
+ const LDM_hashEntry *hashTable, U32 hashTableSize) {
+ U32 i = 0;
+ U32 ctr = 0;
+ for (; i < hashTableSize; i++) {
+ if (hashTable[i].offset == 0) {
+ ctr++;
+ }
+ }
+ printf("Hash table size, empty slots, %% empty: %u, %u, %.3f\n",
+ hashTableSize, ctr,
+ 100.0 * (double)(ctr) / (double)hashTableSize);
+}
-#ifdef COMPUTE_STATS
-/**
- * Outputs compression statistics.
- */
-static void printCompressStats(const LDM_CCtx *cctx) {
- const LDM_compressStats *stats = &(cctx->stats);
+void LDM_printCompressStats(const LDM_compressStats *stats) {
printf("=====================\n");
printf("Compression statistics\n");
- printf("Total number of matches: %u\n", stats->numMatches);
- printf("Average match length: %.1f\n", ((double)stats->totalMatchLength) /
+ //TODO: compute percentage matched?
+ printf("num matches, total match length: %u, %llu\n",
+ stats->numMatches,
+ stats->totalMatchLength);
+ printf("avg match length: %.1f\n", ((double)stats->totalMatchLength) /
(double)stats->numMatches);
- printf("Average literal length: %.1f\n",
+ printf("avg literal length: %.1f\n",
((double)stats->totalLiteralLength) / (double)stats->numMatches);
- printf("Average offset length: %.1f\n",
+ printf("avg offset length: %.1f\n",
((double)stats->totalOffset) / (double)stats->numMatches);
- printf("Num collisions, num hash inserts, %% collisions: %u, %u, %.3f\n",
+ printf("min offset, max offset: %u %u\n",
+ stats->minOffset, stats->maxOffset);
+ printf("num collisions, num hash inserts, %% collisions: %u, %u, %.3f\n",
stats->numCollisions, stats->numHashInserts,
stats->numHashInserts == 0 ?
1.0 : (100.0 * (double)stats->numCollisions) /
(double)stats->numHashInserts);
-
- // Output occupancy of hash table.
- {
- U32 i = 0;
- U32 ctr = 0;
- for (; i < LDM_HASHTABLESIZE_U32; i++) {
- if ((cctx->hashTable)[i].offset == 0) {
- ctr++;
- }
- }
- printf("Hash table size, empty slots, %% empty: %u %u %.3f\n",
- LDM_HASHTABLESIZE_U32, ctr,
- 100.0 * (double)(ctr) / (double)LDM_HASHTABLESIZE_U32);
- }
-
- printf("=====================\n");
}
-#endif
-/**
- * Checks whether the MINMATCH bytes from p are the same as the MINMATCH
- * bytes from match.
- *
- * This assumes MINMATCH is a multiple of four.
- *
- * Return 1 if valid, 0 otherwise.
- */
-static int LDM_isValidMatch(const BYTE *p, const BYTE *match) {
+int LDM_isValidMatch(const BYTE *pIn, const BYTE *pMatch) {
/*
- if (memcmp(p, match, MINMATCH) == 0) {
+ if (memcmp(pIn, pMatch, LDM_MIN_MATCH_LENGTH) == 0) {
return 1;
}
return 0;
*/
//TODO: This seems to be faster for some reason?
- U16 lengthLeft = MINMATCH;
- const BYTE *curP = p;
- const BYTE *curMatch = match;
+ U32 lengthLeft = LDM_MIN_MATCH_LENGTH;
+ const BYTE *curIn = pIn;
+ const BYTE *curMatch = pMatch;
for (; lengthLeft >= 8; lengthLeft -= 8) {
- if (LDM_read64(curP) != LDM_read64(curMatch)) {
+ if (MEM_read64(curIn) != MEM_read64(curMatch)) {
return 0;
}
- curP += 8;
+ curIn += 8;
curMatch += 8;
}
if (lengthLeft > 0) {
- return (LDM_read32(curP) == LDM_read32(curMatch));
+ return (MEM_read32(curIn) == MEM_read32(curMatch));
}
return 1;
}
* b(k,l) = \sum_{i = k}^l ((l - i + 1) * x_i) (mod M)
* checksum(k,l) = a(k,l) + 2^{16} * b(k,l)
*/
-static U32 getChecksum(const char *data, U32 len) {
+static U32 getChecksum(const BYTE *buf, U32 len) {
U32 i;
U32 s1, s2;
- const schar *buf = (const schar *)data;
s1 = s2 = 0;
for (i = 0; i < (len - 4); i += 4) {
s2 += (4 * (s1 + buf[i])) + (3 * buf[i + 1]) +
- (2 * buf[i + 2]) + (buf[i + 3]);
- s1 += buf[i] + buf[i + 1] + buf[i + 2] + buf[i + 3];
+ (2 * buf[i + 2]) + (buf[i + 3]) +
+ (10 * CHECKSUM_CHAR_OFFSET);
+ s1 += buf[i] + buf[i + 1] + buf[i + 2] + buf[i + 3] +
+ + (4 * CHECKSUM_CHAR_OFFSET);
+
}
for(; i < len; i++) {
- s1 += buf[i];
+ s1 += buf[i] + CHECKSUM_CHAR_OFFSET;
s2 += s1;
}
return (s1 & 0xffff) + (s2 << 16);
* Thus toRemove should correspond to data[0].
*/
static U32 updateChecksum(U32 sum, U32 len,
- schar toRemove, schar toAdd) {
+ BYTE toRemove, BYTE toAdd) {
U32 s1 = (sum & 0xffff) - toRemove + toAdd;
- U32 s2 = (sum >> 16) - (toRemove * len) + s1;
+ U32 s2 = (sum >> 16) - ((toRemove + CHECKSUM_CHAR_OFFSET) * len) + s1;
return (s1 & 0xffff) + (s2 << 16);
}
// cctx->nextSum = getChecksum((const char *)cctx->nextIp, LDM_HASH_LENGTH);
cctx->nextSum = updateChecksum(
cctx->lastSum, LDM_HASH_LENGTH,
- (schar)((cctx->lastPosHashed)[0]),
- (schar)((cctx->lastPosHashed)[LDM_HASH_LENGTH]));
+ cctx->lastPosHashed[0],
+ cctx->lastPosHashed[LDM_HASH_LENGTH]);
cctx->nextPosHashed = cctx->nextIp;
cctx->nextHash = checksumToHash(cctx->nextSum);
#ifdef RUN_CHECKS
- check = getChecksum((const char *)cctx->nextIp, LDM_HASH_LENGTH);
+ check = getChecksum(cctx->nextIp, LDM_HASH_LENGTH);
if (check != cctx->nextSum) {
printf("CHECK: setNextHash failed %u %u\n", check, cctx->nextSum);
LDM_CCtx *cctx, hash_t hash, U32 sum) {
#ifdef COMPUTE_STATS
if (cctx->stats.numHashInserts < LDM_HASHTABLESIZE_U32) {
- offset_t offset = (cctx->hashTable)[hash].offset;
+ offset_t offset = cctx->hashTable[hash].offset;
cctx->stats.numHashInserts++;
if (offset != 0 && !LDM_isValidMatch(cctx->ip, offset + cctx->ibase)) {
cctx->stats.numCollisions++;
// Hash only every HASH_ONLY_EVERY times, based on cctx->ip.
// Note: this works only when cctx->step is 1.
if (((cctx->ip - cctx->ibase) & HASH_ONLY_EVERY) == HASH_ONLY_EVERY) {
- (cctx->hashTable)[hash] = (hashEntry){ (offset_t)(cctx->ip - cctx->ibase) };
+ const LDM_hashEntry entry = { cctx->ip - cctx->ibase };
+ cctx->hashTable[hash] = entry;
}
cctx->lastPosHashed = cctx->ip;
* Insert hash of the current position into the hash table.
*/
static void LDM_putHashOfCurrentPosition(LDM_CCtx *cctx) {
- U32 sum = getChecksum((const char *)cctx->ip, LDM_HASH_LENGTH);
+ U32 sum = getChecksum(cctx->ip, LDM_HASH_LENGTH);
hash_t hash = checksumToHash(sum);
#ifdef RUN_CHECKS
return cctx->hashTable[hash].offset + cctx->ibase;
}
-/**
- * Counts the number of bytes that match from pIn and pMatch,
- * up to pInLimit.
- *
- * TODO: make more efficient.
- */
-static unsigned countMatchLength(const BYTE *pIn, const BYTE *pMatch,
- const BYTE *pInLimit) {
+U32 LDM_countMatchLength(const BYTE *pIn, const BYTE *pMatch,
+ const BYTE *pInLimit) {
const BYTE * const pStart = pIn;
while (pIn < pInLimit - 1) {
- BYTE const diff = LDM_readByte(pMatch) ^ LDM_readByte(pIn);
+ BYTE const diff = (*pMatch) ^ *(pIn);
if (!diff) {
pIn++;
pMatch++;
continue;
}
- return (unsigned)(pIn - pStart);
+ return (U32)(pIn - pStart);
}
- return (unsigned)(pIn - pStart);
+ return (U32)(pIn - pStart);
}
-void LDM_readHeader(const void *src, size_t *compressSize,
- size_t *decompressSize) {
- const U32 *ip = (const U32 *)src;
- *compressSize = *ip++;
- *decompressSize = *ip;
+void LDM_readHeader(const void *src, U64 *compressedSize,
+ U64 *decompressedSize) {
+ const BYTE *ip = (const BYTE *)src;
+ *compressedSize = MEM_readLE64(ip);
+ ip += sizeof(U64);
+ *decompressedSize = MEM_readLE64(ip);
+ // ip += sizeof(U64);
}
-/**
- * Initialize a compression context.
- */
-static void initializeCCtx(LDM_CCtx *cctx,
- const void *src, size_t srcSize,
- void *dst, size_t maxDstSize) {
+void LDM_initializeCCtx(LDM_CCtx *cctx,
+ const void *src, size_t srcSize,
+ void *dst, size_t maxDstSize) {
cctx->isize = srcSize;
cctx->maxOSize = maxDstSize;
cctx->iend = cctx->ibase + srcSize;
cctx->ihashLimit = cctx->iend - LDM_HASH_LENGTH;
- cctx->imatchLimit = cctx->iend - MINMATCH;
+ cctx->imatchLimit = cctx->iend - LDM_MIN_MATCH_LENGTH;
cctx->obase = (BYTE *)dst;
cctx->op = (BYTE *)dst;
memset(&(cctx->stats), 0, sizeof(cctx->stats));
memset(cctx->hashTable, 0, sizeof(cctx->hashTable));
+ cctx->stats.minOffset = UINT_MAX;
cctx->lastPosHashed = NULL;
return 0;
}
-/**
- * Write current block (literals, literal length, match offset,
- * match length).
- *
- * Update input pointer, inserting hashes into hash table along the way.
- */
-static void outputBlock(LDM_CCtx *cctx,
- unsigned const literalLength,
- unsigned const offset,
- unsigned const matchLength) {
- BYTE *token = cctx->op++;
-
+void LDM_encodeLiteralLengthAndLiterals(
+ LDM_CCtx *cctx, BYTE *pToken, const U32 literalLength) {
/* Encode the literal length. */
if (literalLength >= RUN_MASK) {
int len = (int)literalLength - RUN_MASK;
- *token = (RUN_MASK << ML_BITS);
+ *pToken = (RUN_MASK << ML_BITS);
for (; len >= 255; len -= 255) {
*(cctx->op)++ = 255;
}
*(cctx->op)++ = (BYTE)len;
} else {
- *token = (BYTE)(literalLength << ML_BITS);
+ *pToken = (BYTE)(literalLength << ML_BITS);
}
/* Encode the literals. */
memcpy(cctx->op, cctx->anchor, literalLength);
cctx->op += literalLength;
+}
+
+void LDM_outputBlock(LDM_CCtx *cctx,
+ const U32 literalLength,
+ const U32 offset,
+ const U32 matchLength) {
+ BYTE *pToken = cctx->op++;
+
+ /* Encode the literal length and literals. */
+ LDM_encodeLiteralLengthAndLiterals(cctx, pToken, literalLength);
/* Encode the offset. */
- LDM_write32(cctx->op, offset);
+ MEM_write32(cctx->op, offset);
cctx->op += LDM_OFFSET_SIZE;
/* Encode the match length. */
if (matchLength >= ML_MASK) {
unsigned matchLengthRemaining = matchLength;
- *token += ML_MASK;
+ *pToken += ML_MASK;
matchLengthRemaining -= ML_MASK;
- LDM_write32(cctx->op, 0xFFFFFFFF);
+ MEM_write32(cctx->op, 0xFFFFFFFF);
while (matchLengthRemaining >= 4*0xFF) {
cctx->op += 4;
- LDM_write32(cctx->op, 0xffffffff);
+ MEM_write32(cctx->op, 0xffffffff);
matchLengthRemaining -= 4*0xFF;
}
cctx->op += matchLengthRemaining / 255;
*(cctx->op)++ = (BYTE)(matchLengthRemaining % 255);
} else {
- *token += (BYTE)(matchLength);
+ *pToken += (BYTE)(matchLength);
}
}
-// TODO: srcSize and maxDstSize is unused
+// TODO: maxDstSize is unused. This function may seg fault when writing
+// beyond the size of dst, as it does not check maxDstSize. Writing to
+// a buffer and performing checks is a possible solution.
+//
+// This is based upon lz4.
size_t LDM_compress(const void *src, size_t srcSize,
void *dst, size_t maxDstSize) {
LDM_CCtx cctx;
- initializeCCtx(&cctx, src, srcSize, dst, maxDstSize);
+ LDM_initializeCCtx(&cctx, src, srcSize, dst, maxDstSize);
/* Hash the first position and put it into the hash table. */
LDM_putHashOfCurrentPosition(&cctx);
* length) and update pointers and hashes.
*/
{
- unsigned const literalLength = (unsigned)(cctx.ip - cctx.anchor);
- unsigned const offset = cctx.ip - match;
- unsigned const matchLength = countMatchLength(
- cctx.ip + MINMATCH, match + MINMATCH, cctx.ihashLimit);
+ const U32 literalLength = cctx.ip - cctx.anchor;
+ const U32 offset = cctx.ip - match;
+ const U32 matchLength = LDM_countMatchLength(
+ cctx.ip + LDM_MIN_MATCH_LENGTH, match + LDM_MIN_MATCH_LENGTH,
+ cctx.ihashLimit);
#ifdef COMPUTE_STATS
cctx.stats.totalLiteralLength += literalLength;
cctx.stats.totalOffset += offset;
- cctx.stats.totalMatchLength += matchLength + MINMATCH;
+ cctx.stats.totalMatchLength += matchLength + LDM_MIN_MATCH_LENGTH;
+ cctx.stats.minOffset =
+ offset < cctx.stats.minOffset ? offset : cctx.stats.minOffset;
+ cctx.stats.maxOffset =
+ offset > cctx.stats.maxOffset ? offset : cctx.stats.maxOffset;
#endif
- outputBlock(&cctx, literalLength, offset, matchLength);
+ LDM_outputBlock(&cctx, literalLength, offset, matchLength);
// Move ip to end of block, inserting hashes at each position.
cctx.nextIp = cctx.ip + cctx.step;
- while (cctx.ip < cctx.anchor + MINMATCH + matchLength + literalLength) {
+ while (cctx.ip < cctx.anchor + LDM_MIN_MATCH_LENGTH +
+ matchLength + literalLength) {
if (cctx.ip > cctx.lastPosHashed) {
// TODO: Simplify.
LDM_updateLastHashFromNextHash(&cctx);
_last_literals:
/* Encode the last literals (no more matches). */
{
- size_t const lastRun = (size_t)(cctx.iend - cctx.anchor);
- if (lastRun >= RUN_MASK) {
- size_t accumulator = lastRun - RUN_MASK;
- *(cctx.op)++ = RUN_MASK << ML_BITS;
- for(; accumulator >= 255; accumulator -= 255) {
- *(cctx.op)++ = 255;
- }
- *(cctx.op)++ = (BYTE)accumulator;
- } else {
- *(cctx.op)++ = (BYTE)(lastRun << ML_BITS);
- }
- memcpy(cctx.op, cctx.anchor, lastRun);
- cctx.op += lastRun;
+ const size_t lastRun = (size_t)(cctx.iend - cctx.anchor);
+ BYTE *pToken = cctx.op++;
+ LDM_encodeLiteralLengthAndLiterals(&cctx, pToken, lastRun);
}
#ifdef COMPUTE_STATS
- printCompressStats(&cctx);
+ LDM_printCompressStats(&cctx.stats);
+ LDM_outputHashtableOccupancy(cctx.hashTable, LDM_HASHTABLESIZE_U32);
#endif
return (cctx.op - (const BYTE *)cctx.obase);
}
-typedef struct LDM_DCtx {
- size_t compressSize;
- size_t maxDecompressSize;
+struct LDM_DCtx {
+ size_t compressedSize;
+ size_t maxDecompressedSize;
const BYTE *ibase; /* Base of input */
const BYTE *ip; /* Current input position */
const BYTE *obase; /* Base of output */
BYTE *op; /* Current output position */
const BYTE *oend; /* End of output */
-} LDM_DCtx;
+};
-static void LDM_initializeDCtx(LDM_DCtx *dctx,
- const void *src, size_t compressSize,
- void *dst, size_t maxDecompressSize) {
- dctx->compressSize = compressSize;
- dctx->maxDecompressSize = maxDecompressSize;
+void LDM_initializeDCtx(LDM_DCtx *dctx,
+ const void *src, size_t compressedSize,
+ void *dst, size_t maxDecompressedSize) {
+ dctx->compressedSize = compressedSize;
+ dctx->maxDecompressedSize = maxDecompressedSize;
dctx->ibase = src;
dctx->ip = (const BYTE *)src;
- dctx->iend = dctx->ip + dctx->compressSize;
+ dctx->iend = dctx->ip + dctx->compressedSize;
dctx->op = dst;
- dctx->oend = dctx->op + dctx->maxDecompressSize;
-
+ dctx->oend = dctx->op + dctx->maxDecompressedSize;
}
-size_t LDM_decompress(const void *src, size_t compressSize,
- void *dst, size_t maxDecompressSize) {
+size_t LDM_decompress(const void *src, size_t compressedSize,
+ void *dst, size_t maxDecompressedSize) {
LDM_DCtx dctx;
- LDM_initializeDCtx(&dctx, src, compressSize, dst, maxDecompressSize);
+ LDM_initializeDCtx(&dctx, src, compressedSize, dst, maxDecompressedSize);
while (dctx.ip < dctx.iend) {
BYTE *cpy;
size_t length, offset;
/* Get the literal length. */
- unsigned const token = *(dctx.ip)++;
+ const unsigned token = *(dctx.ip)++;
if ((length = (token >> ML_BITS)) == RUN_MASK) {
unsigned s;
do {
dctx.op = cpy;
//TODO : dynamic offset size
- offset = LDM_read32(dctx.ip);
+ offset = MEM_read32(dctx.ip);
dctx.ip += LDM_OFFSET_SIZE;
match = dctx.op - offset;
length += s;
} while (s == 255);
}
- length += MINMATCH;
+ length += LDM_MIN_MATCH_LENGTH;
/* Copy match. */
cpy = dctx.op + length;
return dctx.op - (BYTE *)dst;
}
+// TODO: implement and test hash function
+void LDM_test(void) {
+
+}
+
/*
void LDM_test(const void *src, size_t srcSize,
void *dst, size_t maxDstSize) {
#include <stddef.h> /* size_t */
-#define LDM_COMPRESS_SIZE 4
-#define LDM_DECOMPRESS_SIZE 4
+#include "mem.h" // from /lib/common/mem.h
+
+#define LDM_COMPRESS_SIZE 8
+#define LDM_DECOMPRESS_SIZE 8
#define LDM_HEADER_SIZE ((LDM_COMPRESS_SIZE)+(LDM_DECOMPRESS_SIZE))
+#define LDM_OFFSET_SIZE 4
+
+// Defines the size of the hash table.
+#define LDM_MEMORY_USAGE 22
+#define LDM_HASHLOG (LDM_MEMORY_USAGE-2)
+#define LDM_HASHTABLESIZE (1 << (LDM_MEMORY_USAGE))
+#define LDM_HASHTABLESIZE_U32 ((LDM_HASHTABLESIZE) >> 2)
+
+#define WINDOW_SIZE (1 << 25)
+
+//These should be multiples of four.
+#define LDM_MIN_MATCH_LENGTH 8
+#define LDM_HASH_LENGTH 8
+typedef U32 offset_t;
+typedef U32 hash_t;
+typedef struct LDM_hashEntry LDM_hashEntry;
+typedef struct LDM_compressStats LDM_compressStats;
+typedef struct LDM_CCtx LDM_CCtx;
+typedef struct LDM_DCtx LDM_DCtx;
+
+/**
+ * Compresses src into dst.
+ *
+ * NB: This currently ignores maxDstSize and assumes enough space is available.
+ *
+ * Block format (see lz4 documentation for more information):
+ * github.com/lz4/lz4/blob/dev/doc/lz4_Block_format.md
+ *
+ * A block is composed of sequences. Each sequence begins with a token, which
+ * is a one-byte value separated into two 4-bit fields.
+ *
+ * The first field uses the four high bits of the token and encodes the literal
+ * length. If the field value is 0, there is no literal. If it is 15,
+ * additional bytes are added (each ranging from 0 to 255) to the previous
+ * value to produce a total length.
+ *
+ * Following the token and optional length bytes are the literals.
+ *
+ * Next are the 4 bytes representing the offset of the match (2 in lz4),
+ * representing the position to copy the literals.
+ *
+ * The lower four bits of the token encode the match length. With additional
+ * bytes added similarly to the additional literal length bytes after the offset.
+ *
+ * The last sequence is incomplete and stops right after the lieterals.
+ *
+ */
size_t LDM_compress(const void *src, size_t srcSize,
void *dst, size_t maxDstSize);
+/**
+ * Initialize the compression context.
+ */
+void LDM_initializeCCtx(LDM_CCtx *cctx,
+ const void *src, size_t srcSize,
+ void *dst, size_t maxDstSize);
+
+/**
+ * Prints the percentage of the hash table occupied (where occupied is defined
+ * as the entry being non-zero).
+ */
+void LDM_outputHashtableOccupancy(const LDM_hashEntry *hashTable,
+ U32 hashTableSize);
+
+/**
+ * Outputs compression statistics to stdout.
+ */
+void LDM_printCompressStats(const LDM_compressStats *stats);
+/**
+ * Checks whether the LDM_MIN_MATCH_LENGTH bytes from p are the same as the
+ * LDM_MIN_MATCH_LENGTH bytes from match.
+ *
+ * This assumes LDM_MIN_MATCH_LENGTH is a multiple of four.
+ *
+ * Return 1 if valid, 0 otherwise.
+ */
+int LDM_isValidMatch(const BYTE *pIn, const BYTE *pMatch);
+
+/**
+ * Counts the number of bytes that match from pIn and pMatch,
+ * up to pInLimit.
+ */
+U32 LDM_countMatchLength(const BYTE *pIn, const BYTE *pMatch,
+ const BYTE *pInLimit);
+
+/**
+ * Encode the literal length followed by the literals.
+ *
+ * The literal length is written to the upper four bits of pToken, with
+ * additional bytes written to the output as needed (see lz4).
+ *
+ * This is followed by literalLength bytes corresponding to the literals.
+ */
+void LDM_encodeLiteralLengthAndLiterals(
+ LDM_CCtx *cctx, BYTE *pToken, const U32 literalLength);
+
+/**
+ * Write current block (literals, literal length, match offset,
+ * match length).
+ */
+void LDM_outputBlock(LDM_CCtx *cctx,
+ const U32 literalLength,
+ const U32 offset,
+ const U32 matchLength);
+
+/**
+ * Decompresses src into dst.
+ *
+ * Note: assumes src does not have a header.
+ */
size_t LDM_decompress(const void *src, size_t srcSize,
void *dst, size_t maxDstSize);
+/**
+ * Initialize the decompression context.
+ */
+void LDM_initializeDCtx(LDM_DCtx *dctx,
+ const void *src, size_t compressedSize,
+ void *dst, size_t maxDecompressedSize);
+
/**
* Reads the header from src and writes the compressed size and
- * decompressed size into compressSize and decompressSize respectively.
+ * decompressed size into compressedSize and decompressedSize respectively.
+ *
+ * NB: LDM_compress and LDM_decompress currently do not add/read headers.
*/
-void LDM_readHeader(const void *src, size_t *compressSize,
- size_t *decompressSize);
+void LDM_readHeader(const void *src, U64 *compressedSize,
+ U64 *decompressedSize);
-void LDM_test(const void *src, size_t srcSize,
- void *dst, size_t maxDstSize);
+void LDM_test(void);
#endif /* LDM_H */
-// TODO: file size must fit into a U32
-
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include "ldm.h"
+#include "zstd.h"
#define DEBUG
//#define TEST
/* Compress file given by fname and output to oname.
* Returns 0 if successful, error code otherwise.
+ *
+ * TODO: This currently seg faults if the compressed size is > the decompress
+ * size due to the mmapping and output file size allocated to be the input size.
+ * The compress function should check before writing or buffer writes.
*/
static int compress(const char *fname, const char *oname) {
int fdin, fdout;
struct stat statbuf;
char *src, *dst;
- size_t maxCompressSize, compressSize;
+ size_t maxCompressedSize, compressedSize;
/* Open the input file. */
if ((fdin = open(fname, O_RDONLY)) < 0) {
return 1;
}
- maxCompressSize = statbuf.st_size + LDM_HEADER_SIZE;
+ maxCompressedSize = statbuf.st_size + LDM_HEADER_SIZE;
/* Go to the location corresponding to the last byte. */
/* TODO: fallocate? */
- if (lseek(fdout, maxCompressSize - 1, SEEK_SET) == -1) {
+ if (lseek(fdout, maxCompressedSize - 1, SEEK_SET) == -1) {
perror("lseek error");
return 1;
}
}
/* mmap the output file */
- if ((dst = mmap(0, maxCompressSize, PROT_READ | PROT_WRITE,
+ if ((dst = mmap(0, maxCompressedSize, PROT_READ | PROT_WRITE,
MAP_SHARED, fdout, 0)) == (caddr_t) - 1) {
perror("mmap error for output");
return 1;
}
-/*
-#ifdef TEST
- LDM_test(src, statbuf.st_size,
- dst + LDM_HEADER_SIZE, statbuf.st_size);
-#endif
-*/
-
- compressSize = LDM_HEADER_SIZE +
+ compressedSize = LDM_HEADER_SIZE +
LDM_compress(src, statbuf.st_size,
- dst + LDM_HEADER_SIZE, statbuf.st_size);
+ dst + LDM_HEADER_SIZE, maxCompressedSize);
// Write compress and decompress size to header
// TODO: should depend on LDM_DECOMPRESS_SIZE write32
- memcpy(dst, &compressSize, 4);
- memcpy(dst + 4, &(statbuf.st_size), 4);
+ memcpy(dst, &compressedSize, 8);
+ memcpy(dst + 8, &(statbuf.st_size), 8);
#ifdef DEBUG
- printf("Compressed size: %zu\n", compressSize);
+ printf("Compressed size: %zu\n", compressedSize);
printf("Decompressed size: %zu\n", (size_t)statbuf.st_size);
#endif
- // Truncate file to compressSize.
- ftruncate(fdout, compressSize);
+ // Truncate file to compressedSize.
+ ftruncate(fdout, compressedSize);
printf("%25s : %6u -> %7u - %s (%.1f%%)\n", fname,
- (unsigned)statbuf.st_size, (unsigned)compressSize, oname,
- (double)compressSize / (statbuf.st_size) * 100);
+ (unsigned)statbuf.st_size, (unsigned)compressedSize, oname,
+ (double)compressedSize / (statbuf.st_size) * 100);
// Close files.
close(fdin);
int fdin, fdout;
struct stat statbuf;
char *src, *dst;
- size_t compressSize, decompressSize, outSize;
+ U64 compressedSize, decompressedSize;
+ size_t outSize;
/* Open the input file. */
if ((fdin = open(fname, O_RDONLY)) < 0) {
}
/* Read the header. */
- LDM_readHeader(src, &compressSize, &decompressSize);
+ LDM_readHeader(src, &compressedSize, &decompressedSize);
/* Go to the location corresponding to the last byte. */
- if (lseek(fdout, decompressSize - 1, SEEK_SET) == -1) {
+ if (lseek(fdout, decompressedSize - 1, SEEK_SET) == -1) {
perror("lseek error");
return 1;
}
}
/* mmap the output file */
- if ((dst = mmap(0, decompressSize, PROT_READ | PROT_WRITE,
+ if ((dst = mmap(0, decompressedSize, PROT_READ | PROT_WRITE,
MAP_SHARED, fdout, 0)) == (caddr_t) - 1) {
perror("mmap error for output");
return 1;
outSize = LDM_decompress(
src + LDM_HEADER_SIZE, statbuf.st_size - LDM_HEADER_SIZE,
- dst, decompressSize);
+ dst, decompressedSize);
printf("Ret size out: %zu\n", outSize);
ftruncate(fdout, outSize);
}
/* verify */
verify(inpFilename, decFilename);
- return 0;
-}
-
-
-#if 0
-static size_t compress_file(FILE *in, FILE *out, size_t *size_in,
- size_t *size_out) {
- char *src, *buf = NULL;
- size_t r = 1;
- size_t size, n, k, count_in = 0, count_out = 0, offset, frame_size = 0;
-
- src = malloc(BUF_SIZE);
- if (!src) {
- printf("Not enough memory\n");
- goto cleanup;
- }
-
- size = BUF_SIZE + LDM_HEADER_SIZE;
- buf = malloc(size);
- if (!buf) {
- printf("Not enough memory\n");
- goto cleanup;
- }
-
-
- for (;;) {
- k = fread(src, 1, BUF_SIZE, in);
- if (k == 0)
- break;
- count_in += k;
-
- n = LDM_compress(src, buf, k, BUF_SIZE);
-
- // n = k;
- // offset += n;
- offset = k;
- count_out += k;
-
-// k = fwrite(src, 1, offset, out);
-
- k = fwrite(buf, 1, offset, out);
- if (k < offset) {
- if (ferror(out))
- printf("Write failed\n");
- else
- printf("Short write\n");
- goto cleanup;
- }
-
- }
- *size_in = count_in;
- *size_out = count_out;
- r = 0;
- cleanup:
- free(src);
- free(buf);
- return r;
-}
-
-static size_t decompress_file(FILE *in, FILE *out) {
- void *src = malloc(BUF_SIZE);
- void *dst = NULL;
- size_t dst_capacity = BUF_SIZE;
- size_t ret = 1;
- size_t bytes_written = 0;
-
- if (!src) {
- perror("decompress_file(src)");
- goto cleanup;
- }
-
- while (ret != 0) {
- /* Load more input */
- size_t src_size = fread(src, 1, BUF_SIZE, in);
- void *src_ptr = src;
- void *src_end = src_ptr + src_size;
- if (src_size == 0 || ferror(in)) {
- printf("(TODO): Decompress: not enough input or error reading file\n");
- //TODO
- ret = 0;
- goto cleanup;
- }
-
- /* Allocate destination buffer if it hasn't been allocated already */
- if (!dst) {
- dst = malloc(dst_capacity);
- if (!dst) {
- perror("decompress_file(dst)");
- goto cleanup;
- }
- }
- // TODO
-
- /* Decompress:
- * Continue while there is more input to read.
- */
- while (src_ptr != src_end && ret != 0) {
- // size_t dst_size = src_size;
- size_t dst_size = LDM_decompress(src, dst, src_size, dst_capacity);
- size_t written = fwrite(dst, 1, dst_size, out);
-// printf("Writing %zu bytes\n", dst_size);
- bytes_written += dst_size;
- if (written != dst_size) {
- printf("Decompress: Failed to write to file\n");
- goto cleanup;
- }
- src_ptr += src_size;
- src_size = src_end - src_ptr;
- }
-
- /* Update input */
-
- }
-
- printf("Wrote %zu bytes\n", bytes_written);
-
- cleanup:
- free(src);
- free(dst);
-
- return ret;
-}
-
-int main2(int argc, char *argv[]) {
- char inpFilename[256] = { 0 };
- char ldmFilename[256] = { 0 };
- char decFilename[256] = { 0 };
-
- if (argc < 2) {
- printf("Please specify input filename\n");
- return 0;
- }
- snprintf(inpFilename, 256, "%s", argv[1]);
- snprintf(ldmFilename, 256, "%s.ldm", argv[1]);
- snprintf(decFilename, 256, "%s.ldm.dec", argv[1]);
-
- printf("inp = [%s]\n", inpFilename);
- printf("ldm = [%s]\n", ldmFilename);
- printf("dec = [%s]\n", decFilename);
-
- /* compress */
- {
- FILE *inpFp = fopen(inpFilename, "rb");
- FILE *outFp = fopen(ldmFilename, "wb");
- size_t sizeIn = 0;
- size_t sizeOut = 0;
- size_t ret;
- printf("compress : %s -> %s\n", inpFilename, ldmFilename);
- ret = compress_file(inpFp, outFp, &sizeIn, &sizeOut);
- if (ret) {
- printf("compress : failed with code %zu\n", ret);
- return ret;
- }
- printf("%s: %zu → %zu bytes, %.1f%%\n",
- inpFilename, sizeIn, sizeOut,
- (double)sizeOut / sizeIn * 100);
- printf("compress : done\n");
-
- fclose(outFp);
- fclose(inpFp);
- }
-
- /* decompress */
- {
- FILE *inpFp = fopen(ldmFilename, "rb");
- FILE *outFp = fopen(decFilename, "wb");
- size_t ret;
-
- printf("decompress : %s -> %s\n", ldmFilename, decFilename);
- ret = decompress_file(inpFp, outFp);
- if (ret) {
- printf("decompress : failed with code %zu\n", ret);
- return ret;
- }
- printf("decompress : done\n");
-
- fclose(outFp);
- fclose(inpFp);
- }
-
- /* verify */
- {
- FILE *inpFp = fopen(inpFilename, "rb");
- FILE *decFp = fopen(decFilename, "rb");
-
- printf("verify : %s <-> %s\n", inpFilename, decFilename);
- const int cmp = compare(inpFp, decFp);
- if(0 == cmp) {
- printf("verify : OK\n");
- } else {
- printf("verify : NG\n");
- }
-
- fclose(decFp);
- fclose(inpFp);
- }
+#ifdef TEST
+ LDM_test();
+#endif
return 0;
}
-#endif
-
+++ /dev/null
-#include <stdlib.h>
-#include <string.h>
-#include <stdint.h>
-#include <stdio.h>
-
-#include "util.h"
-
-typedef uint8_t BYTE;
-typedef uint16_t U16;
-typedef uint32_t U32;
-typedef int32_t S32;
-typedef uint64_t U64;
-
-unsigned LDM_isLittleEndian(void) {
- const union { U32 u; BYTE c[4]; } one = { 1 };
- return one.c[0];
-}
-
-U16 LDM_read16(const void *memPtr) {
- U16 val;
- memcpy(&val, memPtr, sizeof(val));
- return val;
-}
-
-U16 LDM_readLE16(const void *memPtr) {
- if (LDM_isLittleEndian()) {
- return LDM_read16(memPtr);
- } else {
- const BYTE *p = (const BYTE *)memPtr;
- return (U16)((U16)p[0] + (p[1] << 8));
- }
-}
-
-void LDM_write16(void *memPtr, U16 value){
- memcpy(memPtr, &value, sizeof(value));
-}
-
-void LDM_write32(void *memPtr, U32 value) {
- memcpy(memPtr, &value, sizeof(value));
-}
-
-void LDM_writeLE16(void *memPtr, U16 value) {
- if (LDM_isLittleEndian()) {
- LDM_write16(memPtr, value);
- } else {
- BYTE* p = (BYTE *)memPtr;
- p[0] = (BYTE) value;
- p[1] = (BYTE)(value>>8);
- }
-}
-
-U32 LDM_read32(const void *ptr) {
- return *(const U32 *)ptr;
-}
-
-U64 LDM_read64(const void *ptr) {
- return *(const U64 *)ptr;
-}
-
-void LDM_copy8(void *dst, const void *src) {
- memcpy(dst, src, 8);
-}
-
-BYTE LDM_readByte(const void *memPtr) {
- BYTE val;
- memcpy(&val, memPtr, 1);
- return val;
-}
-
+++ /dev/null
-#ifndef LDM_UTIL_H
-#define LDM_UTIL_H
-
-unsigned LDM_isLittleEndian(void);
-
-uint16_t LDM_read16(const void *memPtr);
-
-uint16_t LDM_readLE16(const void *memPtr);
-
-void LDM_write16(void *memPtr, uint16_t value);
-
-void LDM_write32(void *memPtr, uint32_t value);
-
-void LDM_writeLE16(void *memPtr, uint16_t value);
-
-uint32_t LDM_read32(const void *ptr);
-
-uint64_t LDM_read64(const void *ptr);
-
-void LDM_copy8(void *dst, const void *src);
-
-uint8_t LDM_readByte(const void *ptr);
-
-
-#endif /* LDM_UTIL_H */
projects / thirdparty / zstd.git / commitdiff
