#define WINDOW_SIZE (1 << 20)
//These should be multiples of four.
-#define LDM_HASH_LENGTH 100
-#define MINMATCH 100
+#define LDM_HASH_LENGTH 4
+#define MINMATCH 4
#define ML_BITS 4
#define ML_MASK ((1U<<ML_BITS)-1)
dctx->iend = dctx->ip + dctx->compressSize;
dctx->op = dst;
dctx->oend = dctx->op + dctx->maxDecompressSize;
-
}
size_t LDM_decompress(const void *src, size_t compressSize,
memcpy(&val, memPtr, 1);
return val;
}
-
+++ /dev/null
-#include <stdlib.h>
-#include <string.h>
-#include <stdint.h>
-#include <stdio.h>
-
-#include "ldm.h"
-
-#define LDM_MEMORY_USAGE 14
-#define LDM_HASHLOG (LDM_MEMORY_USAGE-2)
-#define LDM_HASHTABLESIZE (1 << (LDM_MEMORY_USAGE))
-#define LDM_HASHTABLESIZE_U32 ((LDM_HASHTABLESIZE) >> 2)
-#define LDM_HASH_SIZE_U32 (1 << (LDM_HASHLOG))
-
-#define WINDOW_SIZE (1 << 20)
-#define MAX_WINDOW_SIZE 31
-#define HASH_SIZE 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 LDM_DEBUG
-
-typedef uint8_t BYTE;
-typedef uint16_t U16;
-typedef uint32_t U32;
-typedef int32_t S32;
-typedef uint64_t U64;
-
-typedef uint64_t tag;
-
-static unsigned LDM_isLittleEndian(void)
-{
- const union { U32 u; BYTE c[4]; } one = { 1 };
- return one.c[0];
-}
-
-static U16 LDM_read16(const void *memPtr) {
- U16 val;
- memcpy(&val, memPtr, sizeof(val));
- return val;
-}
-
-static 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));
- }
-}
-
-static void LDM_write32(void *memPtr, U32 value) {
- memcpy(memPtr, &value, sizeof(value));
-}
-
-static void LDM_write16(void *memPtr, U16 value) {
- memcpy(memPtr, &value, sizeof(value));
-}
-
-static 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);
- }
-}
-
-static U32 LDM_read32(const void *ptr) {
- return *(const U32 *)ptr;
-}
-
-static U64 LDM_read64(const void *ptr) {
- return *(const U64 *)ptr;
-}
-
-
-static void LDM_copy8(void *dst, const void *src) {
- memcpy(dst, src, 8);
-}
-
-static void LDM_wild_copy(void *dstPtr, const void *srcPtr, void *dstEnd) {
- BYTE *d = (BYTE *)dstPtr;
- const BYTE *s = (const BYTE *)srcPtr;
- BYTE * const e = (BYTE *)dstEnd;
-
- do {
- LDM_copy8(d, s);
- d += 8;
- s += 8;
- } while (d < e);
-
-}
-
-struct hash_entry {
- U64 offset;
- tag t;
-};
-
-static U32 LDM_hash(U32 sequence) {
- return ((sequence * 2654435761U) >> ((32)-LDM_HASHLOG));
-}
-
-static U32 LDM_hash5(U64 sequence) {
- static const U64 prime5bytes = 889523592379ULL;
- static const U64 prime8bytes = 11400714785074694791ULL;
- const U32 hashLog = LDM_HASHLOG;
- if (LDM_isLittleEndian())
- return (U32)(((sequence << 24) * prime5bytes) >> (64 - hashLog));
- else
- return (U32)(((sequence >> 24) * prime8bytes) >> (64 - hashLog));
-}
-
-static U32 LDM_hash_position(const void * const p) {
- return LDM_hash(LDM_read32(p));
-}
-
-static void LDM_put_position_on_hash(const BYTE *p, U32 h, void *tableBase,
- const BYTE *srcBase) {
- U32 *hashTable = (U32 *) tableBase;
- hashTable[h] = (U32)(p - srcBase);
-}
-
-static void LDM_put_position(const BYTE *p, void *tableBase,
- const BYTE *srcBase) {
- U32 const h = LDM_hash_position(p);
- LDM_put_position_on_hash(p, h, tableBase, srcBase);
-}
-
-static const BYTE *LDM_get_position_on_hash(
- U32 h, void *tableBase, const BYTE *srcBase) {
- const U32 * const hashTable = (U32*)tableBase;
- return hashTable[h] + srcBase;
-}
-
-static BYTE LDM_read_byte(const void *memPtr) {
- BYTE val;
- memcpy(&val, memPtr, 1);
- return val;
-}
-
-static unsigned LDM_count(const BYTE *pIn, const BYTE *pMatch,
- const BYTE *pInLimit) {
- const BYTE * const pStart = pIn;
- while (pIn < pInLimit - 1) {
- BYTE const diff = LDM_read_byte(pMatch) ^ LDM_read_byte(pIn);
- if (!diff) {
- pIn++;
- pMatch++;
- continue;
- }
- return (unsigned)(pIn - pStart);
- }
- return (unsigned)(pIn - pStart);
-}
-
-void LDM_read_header(void const *source, size_t *compressed_size,
- size_t *decompressed_size) {
- const U32 *ip = (const U32 *)source;
- *compressed_size = *ip++;
- *decompressed_size = *ip;
-}
-
-size_t LDM_compress(void const *source, void *dest, size_t source_size,
- size_t max_dest_size) {
- const BYTE * const istart = (const BYTE*)source;
- const BYTE *ip = istart;
- const BYTE * const iend = istart + source_size;
- const BYTE *ilimit = iend - HASH_SIZE;
- const BYTE * const matchlimit = iend - HASH_SIZE;
- const BYTE * const mflimit = iend - MINMATCH;
- BYTE *op = (BYTE*) dest;
- U32 hashTable[LDM_HASHTABLESIZE_U32];
- memset(hashTable, 0, sizeof(hashTable));
-
- const BYTE *anchor = (const BYTE *)source;
-// struct LDM_cctx cctx;
- size_t output_size = 0;
-
- U32 forwardH;
-
- /* Hash first byte: put into hash table */
-
- LDM_put_position(ip, hashTable, istart);
- ip++;
- forwardH = LDM_hash_position(ip);
-
- //TODO Loop terminates before ip>=ilimit.
- while (ip < ilimit) {
- const BYTE *match;
- BYTE *token;
-
- /* Find a match */
- {
- const BYTE *forwardIp = ip;
- unsigned step = 1;
-
- do {
- U32 const h = forwardH;
- ip = forwardIp;
- forwardIp += step;
-
- if (forwardIp > mflimit) {
- goto _last_literals;
- }
-
- match = LDM_get_position_on_hash(h, hashTable, istart);
-
- forwardH = LDM_hash_position(forwardIp);
- LDM_put_position_on_hash(ip, h, hashTable, istart);
- } while (ip - match > WINDOW_SIZE ||
- LDM_read64(match) != LDM_read64(ip));
- }
-
- // TODO catchup
- while (ip > anchor && match > istart && ip[-1] == match[-1]) {
- ip--;
- match--;
- }
-
- /* Encode literals */
- {
- unsigned const litLength = (unsigned)(ip - anchor);
- token = op++;
-
-#ifdef LDM_DEBUG
- printf("Cur position: %zu\n", anchor - istart);
- printf("LitLength %zu. (Match offset). %zu\n", litLength, ip - match);
-#endif
- /*
- fwrite(match, 4, 1, stdout);
- printf("\n");
- */
-
- if (litLength >= RUN_MASK) {
- int len = (int)litLength - RUN_MASK;
- *token = (RUN_MASK << ML_BITS);
- for (; len >= 255; len -= 255) {
- *op++ = 255;
- }
- *op++ = (BYTE)len;
- } else {
- *token = (BYTE)(litLength << ML_BITS);
- }
-#ifdef LDM_DEBUG
- printf("Literals ");
- fwrite(anchor, litLength, 1, stdout);
- printf("\n");
-#endif
- memcpy(op, anchor, litLength);
- //LDM_wild_copy(op, anchor, op + litLength);
- op += litLength;
- }
-_next_match:
- /* Encode offset */
- {
- LDM_write32(op, ip - match);
- op += 4;
- }
-
- /* Encode Match Length */
- {
- unsigned matchCode;
- matchCode = LDM_count(ip + MINMATCH, match + MINMATCH,
- matchlimit);
-#ifdef LDM_DEBUG
- printf("Match length %zu\n", matchCode + MINMATCH);
- fwrite(ip, MINMATCH + matchCode, 1, stdout);
- printf("\n");
-#endif
- ip += MINMATCH + matchCode;
- if (matchCode >= ML_MASK) {
- *token += ML_MASK;
- matchCode -= ML_MASK;
- LDM_write32(op, 0xFFFFFFFF);
- while (matchCode >= 4*0xFF) {
- op += 4;
- LDM_write32(op, 0xffffffff);
- matchCode -= 4*0xFF;
- }
- op += matchCode / 255;
- *op++ = (BYTE)(matchCode % 255);
- } else {
- *token += (BYTE)(matchCode);
- }
-#ifdef LDM_DEBUG
- printf("\n");
-#endif
- }
-
- anchor = ip;
-
- LDM_put_position(ip, hashTable, istart);
- forwardH = LDM_hash_position(++ip);
- }
-_last_literals:
- /* Encode last literals */
- {
- size_t const lastRun = (size_t)(iend - anchor);
- if (lastRun >= RUN_MASK) {
- size_t accumulator = lastRun - RUN_MASK;
- *op++ = RUN_MASK << ML_BITS;
- for(; accumulator >= 255; accumulator -= 255) {
- *op++ = 255;
- }
- *op++ = (BYTE)accumulator;
- } else {
- *op++ = (BYTE)(lastRun << ML_BITS);
- }
- memcpy(op, anchor, lastRun);
- op += lastRun;
- }
- return (op - (BYTE *)dest);
-}
-
-size_t LDM_decompress(void const *source, void *dest, size_t compressed_size,
- size_t max_decompressed_size) {
- const BYTE *ip = (const BYTE *)source;
- const BYTE * const iend = ip + compressed_size;
- BYTE *op = (BYTE *)dest;
- BYTE * const oend = op + max_decompressed_size;
- BYTE *cpy;
-
- while (ip < iend) {
- size_t length;
- const BYTE *match;
- size_t offset;
-
- /* get literal length */
- unsigned const token = *ip++;
- if ((length=(token >> ML_BITS)) == RUN_MASK) {
- unsigned s;
- do {
- s = *ip++;
- length += s;
- } while (s == 255);
- }
-#ifdef LDM_DEBUG
- printf("Literal length: %zu\n", length);
-#endif
-
- /* copy literals */
- cpy = op + length;
-#ifdef LDM_DEBUG
- printf("Literals ");
- fwrite(ip, length, 1, stdout);
- printf("\n");
-#endif
- memcpy(op, ip, length);
-// LDM_wild_copy(op, ip, cpy);
- ip += length;
- op = cpy;
-
- /* get offset */
- offset = LDM_read32(ip);
-
-#ifdef LDM_DEBUG
- printf("Offset: %zu\n", offset);
-#endif
- ip += 4;
- match = op - offset;
- // LDM_write32(op, (U32)offset);
-
- /* get matchlength */
- length = token & ML_MASK;
- if (length == ML_MASK) {
- unsigned s;
- do {
- s = *ip++;
- length += s;
- } while (s == 255);
- }
- length += MINMATCH;
-#ifdef LDM_DEBUG
- printf("Match length: %zu\n", length);
-#endif
- /* copy match */
- cpy = op + length;
-
- // Inefficient for now
-
- while (match < cpy - offset && op < oend) {
- *op++ = *match++;
- }
- }
-// memcpy(dest, source, compressed_size);
- return op - (BYTE *)dest;
-}
-
-
+++ /dev/null
-#ifndef LDM_H
-#define LDM_H
-
-#include <stddef.h> /* size_t */
-
-#define LDM_COMPRESS_SIZE 4
-#define LDM_DECOMPRESS_SIZE 4
-#define LDM_HEADER_SIZE ((LDM_COMPRESS_SIZE)+(LDM_DECOMPRESS_SIZE))
-
-size_t LDM_compress(void const *source, void *dest, size_t source_size,
- size_t max_dest_size);
-
-size_t LDM_decompress(void const *source, void *dest, size_t compressed_size,
- size_t max_decompressed_size);
-
-void LDM_read_header(void const *source, size_t *compressed_size,
- size_t *decompressed_size);
-
-#endif /* LDM_H */
+++ /dev/null
-// TODO: file size must fit into a U32
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/time.h>
-#include <sys/types.h>
-#include <sys/mman.h>
-#include <sys/stat.h>
-#include <unistd.h>
-#include <zstd.h>
-
-#include <fcntl.h>
-#include "ldm.h"
-
-// #define BUF_SIZE 16*1024 // Block size
-#define DEBUG
-
-//#define ZSTD
-
-#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;
-}
-#endif
-
-static size_t compress(const char *fname, const char *oname) {
- int fdin, fdout;
- struct stat statbuf;
- char *src, *dst;
-
- /* open the input file */
- if ((fdin = open(fname, O_RDONLY)) < 0) {
- perror("Error in file opening");
- return 1;
- }
-
- /* open the output file */
- if ((fdout = open(oname, O_RDWR | O_CREAT | O_TRUNC, (mode_t)0600)) < 0) {
- perror("Can't create output file");
- return 1;
- }
-
- /* find size of input file */
- if (fstat (fdin, &statbuf) < 0) {
- perror("Fstat error");
- return 1;
- }
- size_t size_in = statbuf.st_size;
-
- /* go to the location corresponding to the last byte */
- if (lseek(fdout, size_in + LDM_HEADER_SIZE - 1, SEEK_SET) == -1) {
- perror("lseek error");
- return 1;
- }
-
- /* write a dummy byte at the last location */
- if (write(fdout, "", 1) != 1) {
- perror("write error");
- return 1;
- }
-
- /* mmap the input file */
- if ((src = mmap(0, statbuf.st_size, PROT_READ, MAP_SHARED, fdin, 0))
- == (caddr_t) - 1) {
- perror("mmap error for input");
- return 1;
- }
- size_t out_size = statbuf.st_size + LDM_HEADER_SIZE;
-
- /* mmap the output file */
- if ((dst = mmap(0, out_size, PROT_READ | PROT_WRITE,
- MAP_SHARED, fdout, 0)) == (caddr_t) - 1) {
- perror("mmap error for output");
- return 1;
- }
-
- #ifdef ZSTD
- size_t size_out = ZSTD_compress(dst, statbuf.st_size,
- src, statbuf.st_size, 1);
- #else
- size_t size_out = LDM_compress(src, dst + LDM_HEADER_SIZE, statbuf.st_size,
- statbuf.st_size);
- size_out += LDM_HEADER_SIZE;
-
- // TODO: should depend on LDM_DECOMPRESS_SIZE write32
- memcpy(dst, &size_out, 4);
- memcpy(dst + 4, &(statbuf.st_size), 4);
- printf("Compressed size: %zu\n", size_out);
- printf("Decompressed size: %zu\n", statbuf.st_size);
- #endif
- ftruncate(fdout, size_out);
-
- printf("%25s : %6u -> %7u - %s (%.1f%%)\n", fname,
- (unsigned)statbuf.st_size, (unsigned)size_out, oname,
- (double)size_out / (statbuf.st_size) * 100);
-
- close(fdin);
- close(fdout);
- return 0;
-}
-
-static size_t decompress(const char *fname, const char *oname) {
- int fdin, fdout;
- struct stat statbuf;
- char *src, *dst;
-
- /* open the input file */
- if ((fdin = open(fname, O_RDONLY)) < 0) {
- perror("Error in file opening");
- return 1;
- }
-
- /* open the output file */
- if ((fdout = open(oname, O_RDWR | O_CREAT | O_TRUNC, (mode_t)0600)) < 0) {
- perror("Can't create output file");
- return 1;
- }
-
- /* find size of input file */
- if (fstat (fdin, &statbuf) < 0) {
- perror("Fstat error");
- return 1;
- }
-
- /* mmap the input file */
- if ((src = mmap(0, statbuf.st_size, PROT_READ, MAP_SHARED, fdin, 0))
- == (caddr_t) - 1) {
- perror("mmap error for input");
- return 1;
- }
-
- /* read header */
- size_t compressed_size, decompressed_size;
- LDM_read_header(src, &compressed_size, &decompressed_size);
-
- printf("Size, compressed_size, decompressed_size: %zu %zu %zu\n",
- statbuf.st_size, compressed_size, decompressed_size);
-
- /* go to the location corresponding to the last byte */
- if (lseek(fdout, decompressed_size - 1, SEEK_SET) == -1) {
- perror("lseek error");
- return 1;
- }
-
- /* write a dummy byte at the last location */
- if (write(fdout, "", 1) != 1) {
- perror("write error");
- return 1;
- }
-
- /* mmap the output file */
- if ((dst = mmap(0, decompressed_size, PROT_READ | PROT_WRITE,
- MAP_SHARED, fdout, 0)) == (caddr_t) - 1) {
- perror("mmap error for output");
- return 1;
- }
-
- /* Copy input file to output file */
-// memcpy(dst, src, statbuf.st_size);
-
- #ifdef ZSTD
- size_t size_out = ZSTD_decompress(dst, decomrpessed_size,
- src + LDM_HEADER_SIZE,
- statbuf.st_size - LDM_HEADER_SIZE);
- #else
- size_t size_out = LDM_decompress(src + LDM_HEADER_SIZE, dst,
- statbuf.st_size - LDM_HEADER_SIZE,
- decompressed_size);
- printf("Ret size out: %zu\n", size_out);
- #endif
- ftruncate(fdout, size_out);
-
- close(fdin);
- close(fdout);
- return 0;
-}
-
-static int compare(FILE *fp0, FILE *fp1) {
- int result = 0;
- while (result == 0) {
- char b0[1024];
- char b1[1024];
- const size_t r0 = fread(b0, 1, sizeof(b0), fp0);
- const size_t r1 = fread(b1, 1, sizeof(b1), fp1);
-
- result = (int)r0 - (int)r1;
-
- if (0 == r0 || 0 == r1) {
- break;
- }
- if (0 == result) {
- result = memcmp(b0, b1, r0);
- }
- }
- return result;
-}
-
-static void verify(const char *inpFilename, const char *decFilename) {
- 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);
-}
-
-int main(int argc, const char *argv[]) {
- const char * const exeName = argv[0];
- char inpFilename[256] = { 0 };
- char ldmFilename[256] = { 0 };
- char decFilename[256] = { 0 };
-
- if (argc < 2) {
- printf("Wrong arguments\n");
- printf("Usage:\n");
- printf("%s FILE\n", exeName);
- return 1;
- }
-
- 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);
-
- struct timeval tv1, tv2;
- /* compress */
- {
- gettimeofday(&tv1, NULL);
- if (compress(inpFilename, ldmFilename)) {
- printf("Compress error");
- return 1;
- }
- gettimeofday(&tv2, NULL);
- printf("Total time = %f seconds\n",
- (double) (tv2.tv_usec - tv1.tv_usec) / 1000000 +
- (double) (tv2.tv_sec - tv1.tv_sec));
- }
-
- /* decompress */
-
- gettimeofday(&tv1, NULL);
- if (decompress(ldmFilename, decFilename)) {
- printf("Decompress error");
- return 1;
- }
- gettimeofday(&tv2, NULL);
- printf("Total time = %f seconds\n",
- (double) (tv2.tv_usec - tv1.tv_usec) / 1000000 +
- (double) (tv2.tv_sec - tv1.tv_sec));
-
- /* verify */
- verify(inpFilename, decFilename);
- return 0;
-}
-
-#if 0
-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);
- }
- return 0;
-}
-#endif
-
+++ /dev/null
-# ################################################################
-# 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`
-
-
-LDFLAGS += -lzstd
-
-.PHONY: default all clean
-
-default: all
-
-all: main-ldm
-
-
-#main : ldm.c main.c
-# $(CC) $(CPPFLAGS) $(CFLAGS) $^ $(LDFLAGS) -o $@
-
-main-ldm : ldm.c main-ldm.c
- $(CC) $(CPPFLAGS) $(CFLAGS) $^ $(LDFLAGS) -o $@
-
-clean:
- @rm -f core *.o tmp* result* *.ldm *.ldm.dec \
- main main-ldm
- @echo Cleaning completed
-
+++ /dev/null
-#include <stdlib.h>
-#include <string.h>
-#include <stdint.h>
-#include <stdio.h>
-
-#include "ldm.h"
-
-#define HASH_EVERY 7
-
-#define LDM_MEMORY_USAGE 14
-#define LDM_HASHLOG (LDM_MEMORY_USAGE-2)
-#define LDM_HASHTABLESIZE (1 << (LDM_MEMORY_USAGE))
-#define LDM_HASHTABLESIZE_U32 ((LDM_HASHTABLESIZE) >> 2)
-#define LDM_HASH_SIZE_U32 (1 << (LDM_HASHLOG))
-
-#define WINDOW_SIZE (1 << 20)
-#define MAX_WINDOW_SIZE 31
-#define HASH_SIZE 8
-#define MINMATCH 8
-
-#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 LDM_DEBUG
-
-typedef uint8_t BYTE;
-typedef uint16_t U16;
-typedef uint32_t U32;
-typedef int32_t S32;
-typedef uint64_t U64;
-
-typedef uint64_t tag;
-
-static unsigned LDM_isLittleEndian(void) {
- const union { U32 u; BYTE c[4]; } one = { 1 };
- return one.c[0];
-}
-
-static U16 LDM_read16(const void *memPtr) {
- U16 val;
- memcpy(&val, memPtr, sizeof(val));
- return val;
-}
-
-static 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));
- }
-}
-
-static void LDM_write16(void *memPtr, U16 value){
- memcpy(memPtr, &value, sizeof(value));
-}
-
-static void LDM_write32(void *memPtr, U32 value) {
- memcpy(memPtr, &value, sizeof(value));
-}
-
-static 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);
- }
-}
-
-static U32 LDM_read32(const void *ptr) {
- return *(const U32 *)ptr;
-}
-
-static U64 LDM_read64(const void *ptr) {
- return *(const U64 *)ptr;
-}
-
-static void LDM_copy8(void *dst, const void *src) {
- memcpy(dst, src, 8);
-}
-
-typedef struct compress_stats {
- U32 num_matches;
- U32 total_match_length;
- U32 total_literal_length;
- U64 total_offset;
-} compress_stats;
-
-static void LDM_printCompressStats(const compress_stats *stats) {
- printf("=====================\n");
- printf("Compression statistics\n");
- printf("Total number of matches: %u\n", stats->num_matches);
- printf("Average match length: %.1f\n", ((double)stats->total_match_length) /
- (double)stats->num_matches);
- printf("Average literal length: %.1f\n",
- ((double)stats->total_literal_length) / (double)stats->num_matches);
- printf("Average offset length: %.1f\n",
- ((double)stats->total_offset) / (double)stats->num_matches);
- printf("=====================\n");
-}
-
-// TODO: unused.
-struct hash_entry {
- U64 offset;
- tag t;
-};
-
-static U32 LDM_hash(U32 sequence) {
- return ((sequence * 2654435761U) >> ((32)-LDM_HASHLOG));
-}
-
-static U32 LDM_hash5(U64 sequence) {
- static const U64 prime5bytes = 889523592379ULL;
- static const U64 prime8bytes = 11400714785074694791ULL;
- const U32 hashLog = LDM_HASHLOG;
- if (LDM_isLittleEndian())
- return (U32)(((sequence << 24) * prime5bytes) >> (64 - hashLog));
- else
- return (U32)(((sequence >> 24) * prime8bytes) >> (64 - hashLog));
-}
-
-static U32 LDM_hash_position(const void * const p) {
- return LDM_hash(LDM_read32(p));
-}
-
-static void LDM_put_position_on_hash(const BYTE *p, U32 h, void *tableBase,
- const BYTE *srcBase) {
- if (((p - srcBase) & HASH_EVERY) != HASH_EVERY) {
- return;
- }
-
- U32 *hashTable = (U32 *) tableBase;
- hashTable[h] = (U32)(p - srcBase);
-}
-
-static void LDM_put_position(const BYTE *p, void *tableBase,
- const BYTE *srcBase) {
- if (((p - srcBase) & HASH_EVERY) != HASH_EVERY) {
- return;
- }
- U32 const h = LDM_hash_position(p);
- LDM_put_position_on_hash(p, h, tableBase, srcBase);
-}
-
-static const BYTE *LDM_get_position_on_hash(
- U32 h, void *tableBase, const BYTE *srcBase) {
- const U32 * const hashTable = (U32*)tableBase;
- return hashTable[h] + srcBase;
-}
-
-static BYTE LDM_read_byte(const void *memPtr) {
- BYTE val;
- memcpy(&val, memPtr, 1);
- return val;
-}
-
-static unsigned LDM_count(const BYTE *pIn, const BYTE *pMatch,
- const BYTE *pInLimit) {
- const BYTE * const pStart = pIn;
- while (pIn < pInLimit - 1) {
- BYTE const diff = LDM_read_byte(pMatch) ^ LDM_read_byte(pIn);
- if (!diff) {
- pIn++;
- pMatch++;
- continue;
- }
- return (unsigned)(pIn - pStart);
- }
- return (unsigned)(pIn - pStart);
-}
-
-void LDM_read_header(const void *src, size_t *compressSize,
- size_t *decompressSize) {
- const U32 *ip = (const U32 *)src;
- *compressSize = *ip++;
- *decompressSize = *ip;
-}
-
-// TODO: maxDstSize is unused
-size_t LDM_compress(const void *src, size_t srcSize,
- void *dst, size_t maxDstSize) {
- const BYTE * const istart = (const BYTE*)src;
- const BYTE *ip = istart;
- const BYTE * const iend = istart + srcSize;
- const BYTE *ilimit = iend - HASH_SIZE;
- const BYTE * const matchlimit = iend - HASH_SIZE;
- const BYTE * const mflimit = iend - MINMATCH;
- BYTE *op = (BYTE*) dst;
-
- compress_stats compressStats = { 0 };
-
- U32 hashTable[LDM_HASHTABLESIZE_U32];
- memset(hashTable, 0, sizeof(hashTable));
-
- const BYTE *anchor = (const BYTE *)src;
-// struct LDM_cctx cctx;
- size_t output_size = 0;
-
- U32 forwardH;
-
- /* Hash first byte: put into hash table */
-
- LDM_put_position(ip, hashTable, istart);
- const BYTE *lastHash = ip;
- ip++;
- forwardH = LDM_hash_position(ip);
-
- //TODO Loop terminates before ip>=ilimit.
- while (ip < ilimit) {
- const BYTE *match;
- BYTE *token;
-
- /* Find a match */
- {
- const BYTE *forwardIp = ip;
- unsigned step = 1;
-
- do {
- U32 const h = forwardH;
- ip = forwardIp;
- forwardIp += step;
-
- if (forwardIp > mflimit) {
- goto _last_literals;
- }
-
- match = LDM_get_position_on_hash(h, hashTable, istart);
-
- forwardH = LDM_hash_position(forwardIp);
- LDM_put_position_on_hash(ip, h, hashTable, istart);
- lastHash = ip;
- } while (ip - match > WINDOW_SIZE ||
- LDM_read64(match) != LDM_read64(ip));
- }
- compressStats.num_matches++;
-
- /* Catchup: look back to extend match from found match */
- while (ip > anchor && match > istart && ip[-1] == match[-1]) {
- ip--;
- match--;
- }
-
- /* Encode literals */
- {
- unsigned const litLength = (unsigned)(ip - anchor);
- token = op++;
-
- compressStats.total_literal_length += litLength;
-
-#ifdef LDM_DEBUG
- printf("Cur position: %zu\n", anchor - istart);
- printf("LitLength %zu. (Match offset). %zu\n", litLength, ip - match);
-#endif
-
- if (litLength >= RUN_MASK) {
- int len = (int)litLength - RUN_MASK;
- *token = (RUN_MASK << ML_BITS);
- for (; len >= 255; len -= 255) {
- *op++ = 255;
- }
- *op++ = (BYTE)len;
- } else {
- *token = (BYTE)(litLength << ML_BITS);
- }
-#ifdef LDM_DEBUG
- printf("Literals ");
- fwrite(anchor, litLength, 1, stdout);
- printf("\n");
-#endif
- memcpy(op, anchor, litLength);
- op += litLength;
- }
-_next_match:
- /* Encode offset */
- {
- /*
- LDM_writeLE16(op, ip-match);
- op += 2;
- */
- LDM_write32(op, ip - match);
- op += 4;
- compressStats.total_offset += (ip - match);
- }
-
- /* Encode Match Length */
- {
- unsigned matchCode;
- matchCode = LDM_count(ip + MINMATCH, match + MINMATCH,
- matchlimit);
-#ifdef LDM_DEBUG
- printf("Match length %zu\n", matchCode + MINMATCH);
- fwrite(ip, MINMATCH + matchCode, 1, stdout);
- printf("\n");
-#endif
- compressStats.total_match_length += matchCode + MINMATCH;
- unsigned ctr = 1;
- ip++;
- for (; ctr < MINMATCH + matchCode; ip++, ctr++) {
- LDM_put_position(ip, hashTable, istart);
- }
-// ip += MINMATCH + matchCode;
- if (matchCode >= ML_MASK) {
- *token += ML_MASK;
- matchCode -= ML_MASK;
- LDM_write32(op, 0xFFFFFFFF);
- while (matchCode >= 4*0xFF) {
- op += 4;
- LDM_write32(op, 0xffffffff);
- matchCode -= 4*0xFF;
- }
- op += matchCode / 255;
- *op++ = (BYTE)(matchCode % 255);
- } else {
- *token += (BYTE)(matchCode);
- }
-#ifdef LDM_DEBUG
- printf("\n");
-
-#endif
- }
-
- anchor = ip;
-
- LDM_put_position(ip, hashTable, istart);
- forwardH = LDM_hash_position(++ip);
- lastHash = ip;
- }
-_last_literals:
- /* Encode last literals */
- {
- size_t const lastRun = (size_t)(iend - anchor);
- if (lastRun >= RUN_MASK) {
- size_t accumulator = lastRun - RUN_MASK;
- *op++ = RUN_MASK << ML_BITS;
- for(; accumulator >= 255; accumulator -= 255) {
- *op++ = 255;
- }
- *op++ = (BYTE)accumulator;
- } else {
- *op++ = (BYTE)(lastRun << ML_BITS);
- }
- memcpy(op, anchor, lastRun);
- op += lastRun;
- }
- LDM_printCompressStats(&compressStats);
- return (op - (BYTE *)dst);
-}
-
-typedef struct LDM_DCtx {
- const BYTE * const ibase; /* Pointer to base of input */
- const BYTE *ip; /* Pointer to current input position */
- const BYTE *iend; /* End of source */
- BYTE *op; /* Pointer to output */
- const BYTE * const oend; /* Pointer to end of output */
-
-} LDM_DCtx;
-
-size_t LDM_decompress(const void *src, size_t compressed_size,
- void *dst, size_t max_decompressed_size) {
- const BYTE *ip = (const BYTE *)src;
- const BYTE * const iend = ip + compressed_size;
- BYTE *op = (BYTE *)dst;
- BYTE * const oend = op + max_decompressed_size;
- BYTE *cpy;
-
- while (ip < iend) {
- size_t length;
- const BYTE *match;
- size_t offset;
-
- /* get literal length */
- unsigned const token = *ip++;
- if ((length=(token >> ML_BITS)) == RUN_MASK) {
- unsigned s;
- do {
- s = *ip++;
- length += s;
- } while (s == 255);
- }
-#ifdef LDM_DEBUG
- printf("Literal length: %zu\n", length);
-#endif
-
- /* copy literals */
- cpy = op + length;
-#ifdef LDM_DEBUG
- printf("Literals ");
- fwrite(ip, length, 1, stdout);
- printf("\n");
-#endif
- memcpy(op, ip, length);
- ip += length;
- op = cpy;
-
- /* get offset */
- /*
- offset = LDM_readLE16(ip);
- ip += 2;
- */
- offset = LDM_read32(ip);
- ip += 4;
-#ifdef LDM_DEBUG
- printf("Offset: %zu\n", offset);
-#endif
- match = op - offset;
- // LDM_write32(op, (U32)offset);
-
- /* get matchlength */
- length = token & ML_MASK;
- if (length == ML_MASK) {
- unsigned s;
- do {
- s = *ip++;
- length += s;
- } while (s == 255);
- }
- length += MINMATCH;
-#ifdef LDM_DEBUG
- printf("Match length: %zu\n", length);
-#endif
- /* copy match */
- cpy = op + length;
-
- // Inefficient for now
- while (match < cpy - offset && op < oend) {
- *op++ = *match++;
- }
- }
- return op - (BYTE *)dst;
-}
-
-
+++ /dev/null
-#ifndef LDM_H
-#define LDM_H
-
-#include <stddef.h> /* size_t */
-
-#define LDM_COMPRESS_SIZE 4
-#define LDM_DECOMPRESS_SIZE 4
-#define LDM_HEADER_SIZE ((LDM_COMPRESS_SIZE)+(LDM_DECOMPRESS_SIZE))
-
-size_t LDM_compress(const void *src, size_t srcSize,
- void *dst, size_t maxDstSize);
-
-size_t LDM_decompress(const void *src, size_t srcSize,
- void *dst, size_t maxDstSize);
-
-void LDM_read_header(const void *src, size_t *compressSize,
- size_t *decompressSize);
-
-#endif /* LDM_H */
+++ /dev/null
-// TODO: file size must fit into a U32
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/time.h>
-#include <sys/types.h>
-#include <sys/mman.h>
-#include <sys/stat.h>
-#include <unistd.h>
-#include <zstd.h>
-
-#include <fcntl.h>
-#include "ldm.h"
-
-// #define BUF_SIZE 16*1024 // Block size
-#define DEBUG
-
-//#define ZSTD
-
-/* Compress file given by fname and output to oname.
- * Returns 0 if successful, error code otherwise.
- */
-static int compress(const char *fname, const char *oname) {
- int fdin, fdout;
- struct stat statbuf;
- char *src, *dst;
-
- /* Open the input file. */
- if ((fdin = open(fname, O_RDONLY)) < 0) {
- perror("Error in file opening");
- return 1;
- }
-
- /* Open the output file. */
- if ((fdout = open(oname, O_RDWR | O_CREAT | O_TRUNC, (mode_t)0600)) < 0) {
- perror("Can't create output file");
- return 1;
- }
-
- /* Find the size of the input file. */
- if (fstat (fdin, &statbuf) < 0) {
- perror("Fstat error");
- return 1;
- }
-
- size_t maxCompressSize = 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) {
- perror("lseek error");
- return 1;
- }
-
- /* Write a dummy byte at the last location. */
- if (write(fdout, "", 1) != 1) {
- perror("write error");
- return 1;
- }
-
- /* mmap the input file. */
- if ((src = mmap(0, statbuf.st_size, PROT_READ, MAP_SHARED, fdin, 0))
- == (caddr_t) - 1) {
- perror("mmap error for input");
- return 1;
- }
-
- /* mmap the output file */
- if ((dst = mmap(0, maxCompressSize, PROT_READ | PROT_WRITE,
- MAP_SHARED, fdout, 0)) == (caddr_t) - 1) {
- perror("mmap error for output");
- return 1;
- }
-
-#ifdef ZSTD
- size_t compressSize = ZSTD_compress(dst, statbuf.st_size,
- src, statbuf.st_size, 1);
-#else
- size_t compressSize = LDM_HEADER_SIZE +
- LDM_compress(src, statbuf.st_size,
- dst + LDM_HEADER_SIZE, statbuf.st_size);
-
- // 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);
-
-#ifdef DEBUG
- printf("Compressed size: %zu\n", compressSize);
- printf("Decompressed size: %zu\n", statbuf.st_size);
-#endif
-#endif
-
- // Truncate file to compressSize.
- ftruncate(fdout, compressSize);
-
- printf("%25s : %6u -> %7u - %s (%.1f%%)\n", fname,
- (unsigned)statbuf.st_size, (unsigned)compressSize, oname,
- (double)compressSize / (statbuf.st_size) * 100);
-
- // Close files.
- close(fdin);
- close(fdout);
- return 0;
-}
-
-/* Decompress file compressed using LDM_compress.
- * The input file should have the LDM_HEADER followed by payload.
- * Returns 0 if succesful, and an error code otherwise.
- */
-static int decompress(const char *fname, const char *oname) {
- int fdin, fdout;
- struct stat statbuf;
- char *src, *dst;
-
- /* Open the input file. */
- if ((fdin = open(fname, O_RDONLY)) < 0) {
- perror("Error in file opening");
- return 1;
- }
-
- /* Open the output file. */
- if ((fdout = open(oname, O_RDWR | O_CREAT | O_TRUNC, (mode_t)0600)) < 0) {
- perror("Can't create output file");
- return 1;
- }
-
- /* Find the size of the input file. */
- if (fstat (fdin, &statbuf) < 0) {
- perror("Fstat error");
- return 1;
- }
-
- /* mmap the input file. */
- if ((src = mmap(0, statbuf.st_size, PROT_READ, MAP_SHARED, fdin, 0))
- == (caddr_t) - 1) {
- perror("mmap error for input");
- return 1;
- }
-
- /* Read the header. */
- size_t compressSize, decompressSize;
- LDM_read_header(src, &compressSize, &decompressSize);
-
-#ifdef DEBUG
- printf("Size, compressSize, decompressSize: %zu %zu %zu\n",
- statbuf.st_size, compressSize, decompressSize);
-#endif
-
- /* Go to the location corresponding to the last byte. */
- if (lseek(fdout, decompressSize - 1, SEEK_SET) == -1) {
- perror("lseek error");
- return 1;
- }
-
- /* write a dummy byte at the last location */
- if (write(fdout, "", 1) != 1) {
- perror("write error");
- return 1;
- }
-
- /* mmap the output file */
- if ((dst = mmap(0, decompressSize, PROT_READ | PROT_WRITE,
- MAP_SHARED, fdout, 0)) == (caddr_t) - 1) {
- perror("mmap error for output");
- return 1;
- }
-
-#ifdef ZSTD
- size_t outSize = ZSTD_decompress(dst, decomrpessed_size,
- src + LDM_HEADER_SIZE,
- statbuf.st_size - LDM_HEADER_SIZE);
-#else
- size_t outSize = LDM_decompress(
- src + LDM_HEADER_SIZE, statbuf.st_size - LDM_HEADER_SIZE,
- dst, decompressSize);
-
- printf("Ret size out: %zu\n", outSize);
- #endif
- ftruncate(fdout, outSize);
-
- close(fdin);
- close(fdout);
- return 0;
-}
-
-/* Compare two files.
- * Returns 0 iff they are the same.
- */
-static int compare(FILE *fp0, FILE *fp1) {
- int result = 0;
- while (result == 0) {
- char b0[1024];
- char b1[1024];
- const size_t r0 = fread(b0, 1, sizeof(b0), fp0);
- const size_t r1 = fread(b1, 1, sizeof(b1), fp1);
-
- result = (int)r0 - (int)r1;
-
- if (0 == r0 || 0 == r1) break;
-
- if (0 == result) result = memcmp(b0, b1, r0);
- }
- return result;
-}
-
-/* Verify the input file is the same as the decompressed file. */
-static void verify(const char *inpFilename, const char *decFilename) {
- 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);
-}
-
-int main(int argc, const char *argv[]) {
- const char * const exeName = argv[0];
- char inpFilename[256] = { 0 };
- char ldmFilename[256] = { 0 };
- char decFilename[256] = { 0 };
-
- if (argc < 2) {
- printf("Wrong arguments\n");
- printf("Usage:\n");
- printf("%s FILE\n", exeName);
- return 1;
- }
-
- 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);
-
- struct timeval tv1, tv2;
-
- /* Compress */
-
- gettimeofday(&tv1, NULL);
- if (compress(inpFilename, ldmFilename)) {
- printf("Compress error");
- return 1;
- }
- gettimeofday(&tv2, NULL);
- printf("Total time = %f seconds\n",
- (double) (tv2.tv_usec - tv1.tv_usec) / 1000000 +
- (double) (tv2.tv_sec - tv1.tv_sec));
-
- /* Decompress */
-
- gettimeofday(&tv1, NULL);
- if (decompress(ldmFilename, decFilename)) {
- printf("Decompress error");
- return 1;
- }
- gettimeofday(&tv2, NULL);
- printf("Total time = %f seconds\n",
- (double) (tv2.tv_usec - tv1.tv_usec) / 1000000 +
- (double) (tv2.tv_sec - tv1.tv_sec));
-
- /* 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);
- }
- return 0;
-}
-#endif
-
-# ################################################################
-# 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`
CFLAGS ?= -O3
all: main-ldm
-
#main : ldm.c main.c
# $(CC) $(CPPFLAGS) $(CFLAGS) $^ $(LDFLAGS) -o $@
--- /dev/null
+This version uses simple lz4-style compression:
+- A 4-byte hash is inserted into the hash table for every position.
+- Hash table replacement policy: direct overwrite.
+++ /dev/null
-# ################################################################
-# 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`
-
-CFLAGS ?= -O3
-DEBUGFLAGS = -Wall -Wextra -Wcast-qual -Wcast-align -Wshadow \
- -Wstrict-aliasing=1 -Wswitch-enum -Wdeclaration-after-statement \
- -Wstrict-prototypes -Wundef -Wpointer-arith -Wformat-security \
- -Wvla -Wformat=2 -Winit-self -Wfloat-equal -Wwrite-strings \
- -Wredundant-decls
-CFLAGS += $(DEBUGFLAGS) $(MOREFLAGS)
-FLAGS = $(CPPFLAGS) $(CFLAGS)
-
-LDFLAGS += -lzstd
-
-.PHONY: default all clean
-
-default: all
-
-all: main-ldm
-
-
-#main : ldm.c main.c
-# $(CC) $(CPPFLAGS) $(CFLAGS) $^ $(LDFLAGS) -o $@
-
-main-ldm : util.c ldm.c main-ldm.c
- $(CC) $(CPPFLAGS) $(CFLAGS) $^ $(LDFLAGS) -o $@
-
-clean:
- @rm -f core *.o tmp* result* *.ldm *.ldm.dec \
- main main-ldm
- @echo Cleaning completed
-
+++ /dev/null
-#include <stdlib.h>
-#include <string.h>
-#include <stdint.h>
-#include <stdio.h>
-
-
-#include "ldm.h"
-#include "util.h"
-
-#define HASH_EVERY 1
-
-#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_HASH_SIZE_U32 (1 << (LDM_HASHLOG))
-
-#define LDM_OFFSET_SIZE 4
-
-#define WINDOW_SIZE (1 << 23)
-#define MAX_WINDOW_SIZE 31
-#define HASH_SIZE 4
-#define LDM_HASH_LENGTH 4
-
-// Should be multiple of four
-#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 LDM_ROLLING_HASH
-#define COMPUTE_STATS
-//#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 LDM_hashEntry {
- offset_t offset;
-} LDM_hashEntry;
-
-typedef struct LDM_compressStats {
- U32 numMatches;
- U32 totalMatchLength;
- U32 totalLiteralLength;
- U64 totalOffset;
-
- U32 numCollisions;
- U32 numHashInserts;
-} LDM_compressStats;
-
-static 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) /
- (double)stats->numMatches);
- printf("Average literal length: %.1f\n",
- ((double)stats->totalLiteralLength) / (double)stats->numMatches);
- printf("Average offset length: %.1f\n",
- ((double)stats->totalOffset) / (double)stats->numMatches);
- 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);
- printf("=====================\n");
-}
-
-typedef struct LDM_CCtx {
- size_t isize; /* Input size */
- size_t maxOSize; /* Maximum output size */
-
- const BYTE *ibase; /* Base of input */
- const BYTE *ip; /* Current input position */
- const BYTE *iend; /* End of input */
-
- // Maximum input position such that hashing at the position does not exceed
- // end of input.
- const BYTE *ihashLimit;
-
- // Maximum input position such that finding a match of at least the minimum
- // match length does not exceed end of input.
- const BYTE *imatchLimit;
-
- const BYTE *obase; /* Base of output */
- BYTE *op; /* Output */
-
- const BYTE *anchor; /* Anchor to start of current (match) block */
-
- LDM_compressStats stats; /* Compression statistics */
-
- LDM_hashEntry hashTable[LDM_HASHTABLESIZE_U32];
-
- const BYTE *lastPosHashed; /* Last position hashed */
- hash_t lastHash; /* Hash corresponding to lastPosHashed */
- const BYTE *nextIp;
- const BYTE *nextPosHashed;
- hash_t nextHash; /* Hash corresponding to nextPosHashed */
-
- // Members for rolling hash.
- U32 lastSum;
- U32 nextSum;
-
- unsigned step;
-
- // DEBUG
- const BYTE *DEBUG_setNextHash;
-} LDM_CCtx;
-
-static int LDM_isValidMatch(const BYTE *p, const BYTE *match) {
- U16 lengthLeft = MINMATCH;
- const BYTE *curP = p;
- const BYTE *curMatch = match;
-
- for (; lengthLeft >= 8; lengthLeft -= 8) {
- if (LDM_read64(curP) != LDM_read64(curMatch)) {
- return 0;
- }
- curP += 8;
- curMatch += 8;
- }
- if (lengthLeft > 0) {
- return LDM_read32(curP) == LDM_read32(curMatch);
- }
- return 1;
-}
-
-
-
-#ifdef LDM_ROLLING_HASH
-/**
- * Convert a sum computed from LDM_getRollingHash to a hash value in the range
- * of the hash table.
- */
-static hash_t LDM_sumToHash(U32 sum) {
- return sum & (LDM_HASH_SIZE_U32 - 1);
-}
-
-static U32 LDM_getRollingHash(const char *data, 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];
- }
- for(; i < len; i++) {
- s1 += buf[i];
- s2 += s1;
- }
- return (s1 & 0xffff) + (s2 << 16);
-}
-
-typedef struct LDM_sumStruct {
- U16 s1, s2;
-} LDM_sumStruct;
-
-static U32 LDM_updateRollingHash(U32 sum, U32 len,
- schar toRemove, schar toAdd) {
- U32 s1 = (sum & 0xffff) - toRemove + toAdd;
- U32 s2 = (sum >> 16) - (toRemove * len) + s1;
-
- return (s1 & 0xffff) + (s2 << 16);
-}
-
-
-/*
-static hash_t LDM_hashPosition(const void * const p) {
- return LDM_sumToHash(LDM_getRollingHash((const char *)p, LDM_HASH_LENGTH));
-}
-*/
-
-/*
-static void LDM_getRollingHashParts(U32 sum, LDM_sumStruct *sumStruct) {
- sumStruct->s1 = sum & 0xffff;
- sumStruct->s2 = sum >> 16;
-}
-*/
-
-static void LDM_setNextHash(LDM_CCtx *cctx) {
-
-#ifdef RUN_CHECKS
- U32 check;
- if ((cctx->nextIp - cctx->ibase != 1) &&
- (cctx->nextIp - cctx->DEBUG_setNextHash != 1)) {
- printf("CHECK debug fail: %zu %zu\n", cctx->nextIp - cctx->ibase,
- cctx->DEBUG_setNextHash - cctx->ibase);
- }
-
- cctx->DEBUG_setNextHash = cctx->nextIp;
-#endif
-
-// cctx->nextSum = LDM_getRollingHash((const char *)cctx->nextIp, LDM_HASH_LENGTH);
- cctx->nextSum = LDM_updateRollingHash(
- cctx->lastSum, LDM_HASH_LENGTH,
- (schar)((cctx->lastPosHashed)[0]),
- (schar)((cctx->lastPosHashed)[LDM_HASH_LENGTH]));
-
-#ifdef RUN_CHECKS
- check = LDM_getRollingHash((const char *)cctx->nextIp, LDM_HASH_LENGTH);
-
- if (check != cctx->nextSum) {
- printf("CHECK: setNextHash failed %u %u\n", check, cctx->nextSum);
-// printf("INFO: %u %u %u\n", LDM_read32(cctx->nextIp),
- }
-#endif
- cctx->nextPosHashed = cctx->nextIp;
- cctx->nextHash = LDM_sumToHash(cctx->nextSum);
-
-#ifdef RUN_CHECKS
- if ((cctx->nextIp - cctx->lastPosHashed) != 1) {
- printf("setNextHash: nextIp != lastPosHashed + 1. %zu %zu %zu\n",
- cctx->nextIp - cctx->ibase, cctx->lastPosHashed - cctx->ibase,
- cctx->ip - cctx->ibase);
- }
-#endif
-
-}
-
-static void LDM_putHashOfCurrentPositionFromHash(
- LDM_CCtx *cctx, hash_t hash, U32 sum) {
- /*
- if (((cctx->ip - cctx->ibase) & HASH_EVERY) != HASH_EVERY) {
- return;
- }
- */
-#ifdef COMPUTE_STATS
- if (cctx->stats.numHashInserts < LDM_HASHTABLESIZE_U32) {
- offset_t offset = (cctx->hashTable)[hash].offset;
- cctx->stats.numHashInserts++;
- if (offset == 0 && !LDM_isValidMatch(cctx->ip, offset + cctx->ibase)) {
- cctx->stats.numCollisions++;
- }
- }
-#endif
- (cctx->hashTable)[hash] = (LDM_hashEntry){ (hash_t)(cctx->ip - cctx->ibase) };
- cctx->lastPosHashed = cctx->ip;
- cctx->lastHash = hash;
- cctx->lastSum = sum;
-}
-
-static void LDM_updateLastHashFromNextHash(LDM_CCtx *cctx) {
-#ifdef RUN_CHECKS
- if (cctx->ip != cctx->nextPosHashed) {
- printf("CHECK failed: updateLastHashFromNextHash %zu\n", cctx->ip - cctx->ibase);
- }
-#endif
- LDM_putHashOfCurrentPositionFromHash(cctx, cctx->nextHash, cctx->nextSum);
-}
-
-static void LDM_putHashOfCurrentPosition(LDM_CCtx *cctx) {
- U32 sum = LDM_getRollingHash((const char *)cctx->ip, LDM_HASH_LENGTH);
- hash_t hash = LDM_sumToHash(sum);
-#ifdef RUN_CHECKS
- if (cctx->nextPosHashed != cctx->ip && (cctx->ip != cctx->ibase)) {
- printf("CHECK failed: putHashOfCurrentPosition %zu\n", cctx->ip - cctx->ibase);
- }
-#endif
-// hash_t hash = LDM_hashPosition(cctx->ip);
- LDM_putHashOfCurrentPositionFromHash(cctx, hash, sum);
-// printf("Offset %zu\n", cctx->ip - cctx->ibase);
-}
-
-#else
-static hash_t LDM_hash(U32 sequence) {
- return ((sequence * 2654435761U) >> ((32)-LDM_HASHLOG));
-}
-
-static hash_t LDM_hashPosition(const void * const p) {
- return LDM_hash(LDM_read32(p));
-}
-
-static void LDM_putHashOfCurrentPositionFromHash(
- LDM_CCtx *cctx, hash_t hash) {
- /*
- if (((cctx->ip - cctx->ibase) & HASH_EVERY) != HASH_EVERY) {
- return;
- }
- */
-#ifdef COMPUTE_STATS
- if (cctx->stats.numHashInserts < LDM_HASHTABLESIZE_U32) {
- offset_t offset = (cctx->hashTable)[hash].offset;
- cctx->stats.numHashInserts++;
- if (offset == 0 && !LDM_isValidMatch(cctx->ip, offset + cctx->ibase)) {
- cctx->stats.numCollisions++;
- }
- }
-#endif
-
- (cctx->hashTable)[hash] = (LDM_hashEntry){ (hash_t)(cctx->ip - cctx->ibase) };
-#ifdef RUN_CHECKS
- if (cctx->ip - cctx->lastPosHashed != 1) {
- printf("putHashError\n");
- }
-#endif
- cctx->lastPosHashed = cctx->ip;
- cctx->lastHash = hash;
-}
-
-static void LDM_putHashOfCurrentPosition(LDM_CCtx *cctx) {
- hash_t hash = LDM_hashPosition(cctx->ip);
- LDM_putHashOfCurrentPositionFromHash(cctx, hash);
-}
-
-#endif
-
-/*
-static hash_t LDM_hash5(U64 sequence) {
- static const U64 prime5bytes = 889523592379ULL;
- static const U64 prime8bytes = 11400714785074694791ULL;
- const U32 hashLog = LDM_HASHLOG;
- if (LDM_isLittleEndian())
- return (((sequence << 24) * prime5bytes) >> (64 - hashLog));
- else
- return (((sequence >> 24) * prime8bytes) >> (64 - hashLog));
-}
-*/
-
-
-static const BYTE *LDM_getPositionOnHash(
- hash_t h, void *tableBase, const BYTE *srcBase) {
- const LDM_hashEntry * const hashTable = (LDM_hashEntry *)tableBase;
- return hashTable[h].offset + srcBase;
-}
-
-
-static unsigned LDM_count(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);
- if (!diff) {
- pIn++;
- pMatch++;
- continue;
- }
- return (unsigned)(pIn - pStart);
- }
- return (unsigned)(pIn - pStart);
-}
-
-void LDM_readHeader(const void *src, size_t *compressSize,
- size_t *decompressSize) {
- const U32 *ip = (const U32 *)src;
- *compressSize = *ip++;
- *decompressSize = *ip;
-}
-
-static void LDM_initializeCCtx(LDM_CCtx *cctx,
- const void *src, size_t srcSize,
- void *dst, size_t maxDstSize) {
- cctx->isize = srcSize;
- cctx->maxOSize = maxDstSize;
-
- cctx->ibase = (const BYTE *)src;
- cctx->ip = cctx->ibase;
- cctx->iend = cctx->ibase + srcSize;
-
-#ifdef LDM_ROLLING_HASH
- cctx->ihashLimit = cctx->iend - LDM_HASH_LENGTH;
-#else
- cctx->ihashLimit = cctx->iend - HASH_SIZE;
-#endif
- cctx->imatchLimit = cctx->iend - MINMATCH;
-
- cctx->obase = (BYTE *)dst;
- cctx->op = (BYTE *)dst;
-
- cctx->anchor = cctx->ibase;
-
- memset(&(cctx->stats), 0, sizeof(cctx->stats));
- memset(cctx->hashTable, 0, sizeof(cctx->hashTable));
-
- cctx->lastPosHashed = NULL;
-
- cctx->step = 1;
- cctx->nextIp = cctx->ip + cctx->step;
- cctx->nextPosHashed = 0;
-
- cctx->DEBUG_setNextHash = 0;
-}
-
-#ifdef LDM_ROLLING_HASH
-static int LDM_findBestMatch(LDM_CCtx *cctx, const BYTE **match) {
- cctx->nextIp = cctx->ip + cctx->step;
-
- do {
- hash_t h;
- U32 sum;
-// printf("Call A\n");
- LDM_setNextHash(cctx);
-// printf("End call a\n");
- h = cctx->nextHash;
- sum = cctx->nextSum;
- cctx->ip = cctx->nextIp;
- cctx->nextIp += cctx->step;
-
- if (cctx->ip > cctx->imatchLimit) {
- return 1;
- }
-
- *match = LDM_getPositionOnHash(h, cctx->hashTable, cctx->ibase);
-
-// // Compute cctx->nextSum and cctx->nextHash from cctx->nextIp.
-// LDM_setNextHash(cctx);
- LDM_putHashOfCurrentPositionFromHash(cctx, h, sum);
-
-// printf("%u %u\n", cctx->lastHash, cctx->nextHash);
- } while (cctx->ip - *match > WINDOW_SIZE ||
- !LDM_isValidMatch(cctx->ip, *match));
-// LDM_read64(*match) != LDM_read64(cctx->ip));
- LDM_setNextHash(cctx);
- return 0;
-}
-#else
-static int LDM_findBestMatch(LDM_CCtx *cctx, const BYTE **match) {
- cctx->nextIp = cctx->ip;
-
- do {
- hash_t const h = cctx->nextHash;
- cctx->ip = cctx->nextIp;
- cctx->nextIp += cctx->step;
-
- if (cctx->ip > cctx->imatchLimit) {
- return 1;
- }
-
- *match = LDM_getPositionOnHash(h, cctx->hashTable, cctx->ibase);
-
- cctx->nextHash = LDM_hashPosition(cctx->nextIp);
- LDM_putHashOfCurrentPositionFromHash(cctx, h);
-
- } while (cctx->ip - *match > WINDOW_SIZE ||
- !LDM_isValidMatch(cctx->ip, *match));
- return 0;
-}
-
-#endif
-
-/**
- * Write current block (literals, literal length, match offset,
- * match length).
- *
- * Update input pointer, inserting hashes into hash table along the
- * way.
- */
-static void LDM_outputBlock(LDM_CCtx *cctx, const BYTE *match) {
- unsigned const literalLength = (unsigned)(cctx->ip - cctx->anchor);
- unsigned const offset = cctx->ip - match;
- unsigned const matchLength = LDM_count(
- cctx->ip + MINMATCH, match + MINMATCH, cctx->ihashLimit);
- BYTE *token = cctx->op++;
-
- cctx->stats.totalLiteralLength += literalLength;
- cctx->stats.totalOffset += offset;
- cctx->stats.totalMatchLength += matchLength + MINMATCH;
-
- /* Encode the literal length. */
- if (literalLength >= RUN_MASK) {
- int len = (int)literalLength - RUN_MASK;
- *token = (RUN_MASK << ML_BITS);
- for (; len >= 255; len -= 255) {
- *(cctx->op)++ = 255;
- }
- *(cctx->op)++ = (BYTE)len;
- } else {
- *token = (BYTE)(literalLength << ML_BITS);
- }
-
- /* Encode the literals. */
- memcpy(cctx->op, cctx->anchor, literalLength);
- cctx->op += literalLength;
-
- /* Encode the offset. */
- LDM_write32(cctx->op, offset);
- cctx->op += LDM_OFFSET_SIZE;
-
- /* Encode match length */
- if (matchLength >= ML_MASK) {
- unsigned matchLengthRemaining = matchLength;
- *token += ML_MASK;
- matchLengthRemaining -= ML_MASK;
- LDM_write32(cctx->op, 0xFFFFFFFF);
- while (matchLengthRemaining >= 4*0xFF) {
- cctx->op += 4;
- LDM_write32(cctx->op, 0xffffffff);
- matchLengthRemaining -= 4*0xFF;
- }
- cctx->op += matchLengthRemaining / 255;
- *(cctx->op)++ = (BYTE)(matchLengthRemaining % 255);
- } else {
- *token += (BYTE)(matchLength);
- }
-
-// LDM_setNextHash(cctx);
-// cctx->ip = cctx->lastPosHashed + 1;
-// cctx->nextIp = cctx->ip + cctx->step;
-// printf("HERE: %zu %zu %zu\n", cctx->ip - cctx->ibase,
-// cctx->lastPosHashed - cctx->ibase, cctx->nextIp - cctx->ibase);
-
- cctx->nextIp = cctx->ip + cctx->step;
-
- while (cctx->ip < cctx->anchor + MINMATCH + matchLength + literalLength) {
-// printf("Loop\n");
- if (cctx->ip > cctx->lastPosHashed) {
- LDM_updateLastHashFromNextHash(cctx);
-// LDM_putHashOfCurrentPosition(cctx);
-#ifdef LDM_ROLLING_HASH
- LDM_setNextHash(cctx);
-#endif
- }
- /*
- printf("Call b %zu %zu %zu\n",
- cctx->lastPosHashed - cctx->ibase,
- cctx->nextIp - cctx->ibase,
- cctx->ip - cctx->ibase);
- */
-// printf("end call b\n");
- cctx->ip++;
- cctx->nextIp++;
- }
-
-// printf("There: %zu %zu\n", cctx->ip - cctx->ibase, cctx->lastPosHashed - cctx->ibase);
-}
-
-// TODO: srcSize and maxDstSize is unused
-size_t LDM_compress(const void *src, size_t srcSize,
- void *dst, size_t maxDstSize) {
- LDM_CCtx cctx;
- LDM_initializeCCtx(&cctx, src, srcSize, dst, maxDstSize);
-
- /* Hash the first position and put it into the hash table. */
- LDM_putHashOfCurrentPosition(&cctx);
-#ifdef LDM_ROLLING_HASH
-// LDM_setNextHash(&cctx);
-// tmp_hash = LDM_updateRollingHash(cctx.lastSum, LDM_HASH_LENGTH,
-// cctx.ip[0], cctx.ip[LDM_HASH_LENGTH]);
-// printf("Update test: %u %u\n", tmp_hash, cctx.nextSum);
-// cctx.ip++;
-#else
- cctx.ip++;
- cctx.nextHash = LDM_hashPosition(cctx.ip);
-#endif
-
- // TODO: loop condition is not accurate.
- while (1) {
- const BYTE *match;
-// printf("Start of loop\n");
-
- /**
- * Find a match.
- * If no more matches can be found (i.e. the length of the remaining input
- * is less than the minimum match length), then stop searching for matches
- * and encode the final literals.
- */
- if (LDM_findBestMatch(&cctx, &match) != 0) {
- goto _last_literals;
- }
-// printf("End of match finding\n");
-
- cctx.stats.numMatches++;
-
- /**
- * Catch up: look back to extend the match backwards from the found match.
- */
- while (cctx.ip > cctx.anchor && match > cctx.ibase &&
- cctx.ip[-1] == match[-1]) {
-// printf("Catch up\n");
- cctx.ip--;
- match--;
- }
-
- /**
- * Write current block (literals, literal length, match offset, match
- * length) and update pointers and hashes.
- */
- LDM_outputBlock(&cctx, match);
-// printf("End of loop\n");
-
- // Set start of next block to current input pointer.
- cctx.anchor = cctx.ip;
- LDM_updateLastHashFromNextHash(&cctx);
-// LDM_putHashOfCurrentPosition(&cctx);
-#ifndef LDM_ROLLING_HASH
- cctx.ip++;
-#endif
-
- /*
- LDM_putHashOfCurrentPosition(&cctx);
- printf("Call c\n");
- LDM_setNextHash(&cctx);
- printf("End call c\n");
- cctx.ip++;
- cctx.nextIp++;
- */
- }
-_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;
- }
- LDM_printCompressStats(&cctx.stats);
- return (cctx.op - (const BYTE *)cctx.obase);
-}
-
-typedef struct LDM_DCtx {
- size_t compressSize;
- size_t maxDecompressSize;
-
- const BYTE *ibase; /* Base of input */
- const BYTE *ip; /* Current input position */
- const BYTE *iend; /* End of source */
-
- 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;
-
- dctx->ibase = src;
- dctx->ip = (const BYTE *)src;
- dctx->iend = dctx->ip + dctx->compressSize;
- dctx->op = dst;
- dctx->oend = dctx->op + dctx->maxDecompressSize;
-
-}
-
-size_t LDM_decompress(const void *src, size_t compressSize,
- void *dst, size_t maxDecompressSize) {
- LDM_DCtx dctx;
- LDM_initializeDCtx(&dctx, src, compressSize, dst, maxDecompressSize);
-
- while (dctx.ip < dctx.iend) {
- BYTE *cpy;
- const BYTE *match;
- size_t length, offset;
-
- /* Get the literal length. */
- unsigned const token = *(dctx.ip)++;
- if ((length = (token >> ML_BITS)) == RUN_MASK) {
- unsigned s;
- do {
- s = *(dctx.ip)++;
- length += s;
- } while (s == 255);
- }
-
- /* Copy literals. */
- cpy = dctx.op + length;
- memcpy(dctx.op, dctx.ip, length);
- dctx.ip += length;
- dctx.op = cpy;
-
- //TODO : dynamic offset size
- offset = LDM_read32(dctx.ip);
- dctx.ip += LDM_OFFSET_SIZE;
- match = dctx.op - offset;
-
- /* Get the match length. */
- length = token & ML_MASK;
- if (length == ML_MASK) {
- unsigned s;
- do {
- s = *(dctx.ip)++;
- length += s;
- } while (s == 255);
- }
- length += MINMATCH;
-
- /* Copy match. */
- cpy = dctx.op + length;
-
- // Inefficient for now.
- while (match < cpy - offset && dctx.op < dctx.oend) {
- *(dctx.op)++ = *match++;
- }
- }
- return dctx.op - (BYTE *)dst;
-}
-
-void LDM_test(const void *src, size_t srcSize,
- void *dst, size_t maxDstSize) {
-#ifdef LDM_ROLLING_HASH
- const BYTE *ip = (const BYTE *)src + 1125;
- U32 sum = LDM_getRollingHash((const char *)ip, LDM_HASH_LENGTH);
- U32 sum2;
- ++ip;
- for (; ip < (const BYTE *)src + 1125 + 100; ip++) {
- sum2 = LDM_updateRollingHash(sum, LDM_HASH_LENGTH,
- ip[-1], ip[LDM_HASH_LENGTH - 1]);
- sum = LDM_getRollingHash((const char *)ip, LDM_HASH_LENGTH);
- printf("TEST HASH: %zu %u %u\n", ip - (const BYTE *)src, sum, sum2);
- }
-#endif
-}
-
-
+++ /dev/null
-#ifndef LDM_H
-#define LDM_H
-
-#include <stddef.h> /* size_t */
-
-#define LDM_COMPRESS_SIZE 4
-#define LDM_DECOMPRESS_SIZE 4
-#define LDM_HEADER_SIZE ((LDM_COMPRESS_SIZE)+(LDM_DECOMPRESS_SIZE))
-
-size_t LDM_compress(const void *src, size_t srcSize,
- void *dst, size_t maxDstSize);
-
-size_t LDM_decompress(const void *src, size_t srcSize,
- void *dst, size_t maxDstSize);
-
-void LDM_readHeader(const void *src, size_t *compressSize,
- size_t *decompressSize);
-
-void LDM_test(const void *src, size_t srcSize,
- void *dst, size_t maxDstSize);
-
-#endif /* LDM_H */
+++ /dev/null
-// TODO: file size must fit into a U32
-
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <sys/time.h>
-#include <sys/types.h>
-#include <sys/mman.h>
-#include <sys/stat.h>
-#include <unistd.h>
-#include <zstd.h>
-
-#include <fcntl.h>
-#include "ldm.h"
-
-// #define BUF_SIZE 16*1024 // Block size
-#define DEBUG
-//#define TEST
-
-//#define ZSTD
-
-/* Compress file given by fname and output to oname.
- * Returns 0 if successful, error code otherwise.
- */
-static int compress(const char *fname, const char *oname) {
- int fdin, fdout;
- struct stat statbuf;
- char *src, *dst;
- size_t maxCompressSize, compressSize;
-
- /* Open the input file. */
- if ((fdin = open(fname, O_RDONLY)) < 0) {
- perror("Error in file opening");
- return 1;
- }
-
- /* Open the output file. */
- if ((fdout = open(oname, O_RDWR | O_CREAT | O_TRUNC, (mode_t)0600)) < 0) {
- perror("Can't create output file");
- return 1;
- }
-
- /* Find the size of the input file. */
- if (fstat (fdin, &statbuf) < 0) {
- perror("Fstat error");
- return 1;
- }
-
- maxCompressSize = 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) {
- perror("lseek error");
- return 1;
- }
-
- /* Write a dummy byte at the last location. */
- if (write(fdout, "", 1) != 1) {
- perror("write error");
- return 1;
- }
-
- /* mmap the input file. */
- if ((src = mmap(0, statbuf.st_size, PROT_READ, MAP_SHARED, fdin, 0))
- == (caddr_t) - 1) {
- perror("mmap error for input");
- return 1;
- }
-
- /* mmap the output file */
- if ((dst = mmap(0, maxCompressSize, 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
-
-#ifdef ZSTD
- compressSize = ZSTD_compress(dst, statbuf.st_size,
- src, statbuf.st_size, 1);
-#else
- compressSize = LDM_HEADER_SIZE +
- LDM_compress(src, statbuf.st_size,
- dst + LDM_HEADER_SIZE, statbuf.st_size);
-
- // 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);
-
-#ifdef DEBUG
- printf("Compressed size: %zu\n", compressSize);
- printf("Decompressed size: %zu\n", (size_t)statbuf.st_size);
-#endif
-#endif
-
- // Truncate file to compressSize.
- ftruncate(fdout, compressSize);
-
- printf("%25s : %6u -> %7u - %s (%.1f%%)\n", fname,
- (unsigned)statbuf.st_size, (unsigned)compressSize, oname,
- (double)compressSize / (statbuf.st_size) * 100);
-
- // Close files.
- close(fdin);
- close(fdout);
- return 0;
-}
-
-/* Decompress file compressed using LDM_compress.
- * The input file should have the LDM_HEADER followed by payload.
- * Returns 0 if succesful, and an error code otherwise.
- */
-static int decompress(const char *fname, const char *oname) {
- int fdin, fdout;
- struct stat statbuf;
- char *src, *dst;
- size_t compressSize, decompressSize, outSize;
-
- /* Open the input file. */
- if ((fdin = open(fname, O_RDONLY)) < 0) {
- perror("Error in file opening");
- return 1;
- }
-
- /* Open the output file. */
- if ((fdout = open(oname, O_RDWR | O_CREAT | O_TRUNC, (mode_t)0600)) < 0) {
- perror("Can't create output file");
- return 1;
- }
-
- /* Find the size of the input file. */
- if (fstat (fdin, &statbuf) < 0) {
- perror("Fstat error");
- return 1;
- }
-
- /* mmap the input file. */
- if ((src = mmap(0, statbuf.st_size, PROT_READ, MAP_SHARED, fdin, 0))
- == (caddr_t) - 1) {
- perror("mmap error for input");
- return 1;
- }
-
- /* Read the header. */
- LDM_readHeader(src, &compressSize, &decompressSize);
-
- /* Go to the location corresponding to the last byte. */
- if (lseek(fdout, decompressSize - 1, SEEK_SET) == -1) {
- perror("lseek error");
- return 1;
- }
-
- /* write a dummy byte at the last location */
- if (write(fdout, "", 1) != 1) {
- perror("write error");
- return 1;
- }
-
- /* mmap the output file */
- if ((dst = mmap(0, decompressSize, PROT_READ | PROT_WRITE,
- MAP_SHARED, fdout, 0)) == (caddr_t) - 1) {
- perror("mmap error for output");
- return 1;
- }
-
-#ifdef ZSTD
- outSize = ZSTD_decompress(dst, decomrpessed_size,
- src + LDM_HEADER_SIZE,
- statbuf.st_size - LDM_HEADER_SIZE);
-#else
- outSize = LDM_decompress(
- src + LDM_HEADER_SIZE, statbuf.st_size - LDM_HEADER_SIZE,
- dst, decompressSize);
-
- printf("Ret size out: %zu\n", outSize);
- #endif
- ftruncate(fdout, outSize);
-
- close(fdin);
- close(fdout);
- return 0;
-}
-
-/* Compare two files.
- * Returns 0 iff they are the same.
- */
-static int compare(FILE *fp0, FILE *fp1) {
- int result = 0;
- while (result == 0) {
- char b0[1024];
- char b1[1024];
- const size_t r0 = fread(b0, 1, sizeof(b0), fp0);
- const size_t r1 = fread(b1, 1, sizeof(b1), fp1);
-
- result = (int)r0 - (int)r1;
-
- if (0 == r0 || 0 == r1) break;
-
- if (0 == result) result = memcmp(b0, b1, r0);
- }
- return result;
-}
-
-/* Verify the input file is the same as the decompressed file. */
-static void verify(const char *inpFilename, const char *decFilename) {
- 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);
-}
-
-int main(int argc, const char *argv[]) {
- const char * const exeName = argv[0];
- char inpFilename[256] = { 0 };
- char ldmFilename[256] = { 0 };
- char decFilename[256] = { 0 };
-
- if (argc < 2) {
- printf("Wrong arguments\n");
- printf("Usage:\n");
- printf("%s FILE\n", exeName);
- return 1;
- }
-
- 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 */
- {
- struct timeval tv1, tv2;
- gettimeofday(&tv1, NULL);
- if (compress(inpFilename, ldmFilename)) {
- printf("Compress error");
- return 1;
- }
- gettimeofday(&tv2, NULL);
- printf("Total compress time = %f seconds\n",
- (double) (tv2.tv_usec - tv1.tv_usec) / 1000000 +
- (double) (tv2.tv_sec - tv1.tv_sec));
- }
-
- /* Decompress */
- {
- struct timeval tv1, tv2;
- gettimeofday(&tv1, NULL);
- if (decompress(ldmFilename, decFilename)) {
- printf("Decompress error");
- return 1;
- }
- gettimeofday(&tv2, NULL);
- printf("Total decompress time = %f seconds\n",
- (double) (tv2.tv_usec - tv1.tv_usec) / 1000000 +
- (double) (tv2.tv_sec - tv1.tv_sec));
- }
- /* 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);
- }
- 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 */
-# ################################################################
-# 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`
CFLAGS ?= -O3
all: main-ldm
-
-#main : ldm.c main.c
-# $(CC) $(CPPFLAGS) $(CFLAGS) $^ $(LDFLAGS) -o $@
-
main-ldm : util.c ldm.c main-ldm.c
$(CC) $(CPPFLAGS) $(CFLAGS) $^ $(LDFLAGS) -o $@
clean:
@rm -f core *.o tmp* result* *.ldm *.ldm.dec \
- main main-ldm
+ main-ldm
@echo Cleaning completed
--- /dev/null
+This version uses simple lz4-style compression with a rolling hash.
+- A rolling checksum based on rsync's Adler-32 style checksum is used.
+- The checksum is hashed using lz4's hash function.
+- Hash table replacement policy: direct overwrite.
+- The length of input to the hash function can be set with LDM_HASH_LENGTH.
#define WINDOW_SIZE (1 << 20)
//These should be multiples of four.
-#define LDM_HASH_LENGTH 100
-#define MINMATCH 100
+#define LDM_HASH_LENGTH 4
+#define MINMATCH 4
#define ML_BITS 4
#define ML_MASK ((1U<<ML_BITS)-1)
const BYTE *DEBUG_setNextHash;
} LDM_CCtx;
+#ifdef COMPUTE_STATS
/**
* Outputs compression statistics.
*/
static void printCompressStats(const LDM_CCtx *cctx) {
const LDM_compressStats *stats = &(cctx->stats);
-#ifdef COMPUTE_STATS
printf("=====================\n");
printf("Compression statistics\n");
printf("Total number of matches: %u\n", stats->numMatches);
}
printf("=====================\n");
-#endif
}
+#endif
/**
* Checks whether the MINMATCH bytes from p are the same as the MINMATCH
projects / thirdparty / zstd.git / commitdiff
