You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

212 lines
5.3 KiB

// LZ4 streaming API example : line-by-line logfile compression
// by Takayuki Matsuoka
#if defined(_MSC_VER) && (_MSC_VER <= 1800) /* Visual Studio <= 2013 */
# define _CRT_SECURE_NO_WARNINGS
# define snprintf sprintf_s
#endif
#include "lz4.h"
#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
static size_t write_uint16(FILE* fp, uint16_t i)
{
return fwrite(&i, sizeof(i), 1, fp);
}
static size_t write_bin(FILE* fp, const void* array, int arrayBytes)
{
return fwrite(array, 1, arrayBytes, fp);
}
static size_t read_uint16(FILE* fp, uint16_t* i)
{
return fread(i, sizeof(*i), 1, fp);
}
static size_t read_bin(FILE* fp, void* array, int arrayBytes)
{
return fread(array, 1, arrayBytes, fp);
}
static void test_compress(
FILE* outFp,
FILE* inpFp,
size_t messageMaxBytes,
size_t ringBufferBytes)
{
LZ4_stream_t* const lz4Stream = LZ4_createStream();
const size_t cmpBufBytes = LZ4_COMPRESSBOUND(messageMaxBytes);
char* const cmpBuf = (char*) malloc(cmpBufBytes);
char* const inpBuf = (char*) malloc(ringBufferBytes);
int inpOffset = 0;
for ( ; ; )
{
char* const inpPtr = &inpBuf[inpOffset];
#if 0
// Read random length data to the ring buffer.
const int randomLength = (rand() % messageMaxBytes) + 1;
const int inpBytes = (int) read_bin(inpFp, inpPtr, randomLength);
if (0 == inpBytes) break;
#else
// Read line to the ring buffer.
int inpBytes = 0;
if (!fgets(inpPtr, (int) messageMaxBytes, inpFp))
break;
inpBytes = (int) strlen(inpPtr);
#endif
{
const int cmpBytes = LZ4_compress_fast_continue(
lz4Stream, inpPtr, cmpBuf, inpBytes, cmpBufBytes, 1);
if (cmpBytes <= 0) break;
write_uint16(outFp, (uint16_t) cmpBytes);
write_bin(outFp, cmpBuf, cmpBytes);
// Add and wraparound the ringbuffer offset
inpOffset += inpBytes;
if ((size_t)inpOffset >= ringBufferBytes - messageMaxBytes) inpOffset = 0;
}
}
write_uint16(outFp, 0);
free(inpBuf);
free(cmpBuf);
LZ4_freeStream(lz4Stream);
}
static void test_decompress(
FILE* outFp,
FILE* inpFp,
size_t messageMaxBytes,
size_t ringBufferBytes)
{
LZ4_streamDecode_t* const lz4StreamDecode = LZ4_createStreamDecode();
char* const cmpBuf = (char*) malloc(LZ4_COMPRESSBOUND(messageMaxBytes));
char* const decBuf = (char*) malloc(ringBufferBytes);
int decOffset = 0;
for ( ; ; )
{
uint16_t cmpBytes = 0;
if (read_uint16(inpFp, &cmpBytes) != 1) break;
if (cmpBytes == 0) break;
if (read_bin(inpFp, cmpBuf, cmpBytes) != cmpBytes) break;
{
char* const decPtr = &decBuf[decOffset];
const int decBytes = LZ4_decompress_safe_continue(
lz4StreamDecode, cmpBuf, decPtr, cmpBytes, (int) messageMaxBytes);
if (decBytes <= 0) break;
write_bin(outFp, decPtr, decBytes);
// Add and wraparound the ringbuffer offset
decOffset += decBytes;
if ((size_t)decOffset >= ringBufferBytes - messageMaxBytes) decOffset = 0;
}
}
free(decBuf);
free(cmpBuf);
LZ4_freeStreamDecode(lz4StreamDecode);
}
static int compare(FILE* f0, FILE* f1)
{
int result = 0;
const size_t tempBufferBytes = 65536;
char* const b0 = (char*) malloc(tempBufferBytes);
char* const b1 = (char*) malloc(tempBufferBytes);
while(0 == result)
{
const size_t r0 = fread(b0, 1, tempBufferBytes, f0);
const size_t r1 = fread(b1, 1, tempBufferBytes, f1);
result = (int) r0 - (int) r1;
if (0 == r0 || 0 == r1) break;
if (0 == result) result = memcmp(b0, b1, r0);
}
free(b1);
free(b0);
return result;
}
int main(int argc, char* argv[])
{
enum {
MESSAGE_MAX_BYTES = 1024,
RING_BUFFER_BYTES = 1024 * 256 + MESSAGE_MAX_BYTES,
};
char inpFilename[256] = { 0 };
char lz4Filename[256] = { 0 };
char decFilename[256] = { 0 };
if (argc < 2)
{
printf("Please specify input filename\n");
return 0;
}
snprintf(inpFilename, 256, "%s", argv[1]);
snprintf(lz4Filename, 256, "%s.lz4s", argv[1]);
snprintf(decFilename, 256, "%s.lz4s.dec", argv[1]);
printf("inp = [%s]\n", inpFilename);
printf("lz4 = [%s]\n", lz4Filename);
printf("dec = [%s]\n", decFilename);
// compress
{
FILE* inpFp = fopen(inpFilename, "rb");
FILE* outFp = fopen(lz4Filename, "wb");
test_compress(outFp, inpFp, MESSAGE_MAX_BYTES, RING_BUFFER_BYTES);
fclose(outFp);
fclose(inpFp);
}
// decompress
{
FILE* inpFp = fopen(lz4Filename, "rb");
FILE* outFp = fopen(decFilename, "wb");
test_decompress(outFp, inpFp, MESSAGE_MAX_BYTES, RING_BUFFER_BYTES);
fclose(outFp);
fclose(inpFp);
}
// verify
{
FILE* inpFp = fopen(inpFilename, "rb");
FILE* decFp = fopen(decFilename, "rb");
const int cmp = compare(inpFp, decFp);
if (0 == cmp)
printf("Verify : OK\n");
else
printf("Verify : NG\n");
fclose(decFp);
fclose(inpFp);
}
return 0;
}