zstd/contrib/adaptive-compression/v1.c

74 lines
2.1 KiB
C

#define DISPLAY(...) fprintf(stderr, __VA_ARGS__)
#define FILE_CHUNK_SIZE 4 << 20
typedef unsigned char BYTE;
#include <stdio.h>
#include <stdlib.h>
#include "zstd.h"
/* return 0 if successful, else return error */
int main(int argCount, const char* argv[])
{
const char* const srcFilename = argv[1];
const char* const dstFilename = argv[2];
FILE* const srcFile = fopen(srcFilename, "rb");
FILE* const dstFile = fopen(dstFilename, "wb");
BYTE* const src = malloc(FILE_CHUNK_SIZE);
size_t const dstSize = ZSTD_compressBound(FILE_CHUNK_SIZE);
BYTE* const dst = malloc(dstSize);
int ret = 0;
/* checking for errors */
if (!srcFilename || !dstFilename || !src || !dst) {
DISPLAY("Error: initial variables could not be allocated\n");
ret = 1;
goto cleanup;
}
/* compressing in blocks */
for ( ; ; ) {
size_t const readSize = fread(src, 1, FILE_CHUNK_SIZE, srcFile);
if (readSize != FILE_CHUNK_SIZE && !feof(srcFile)) {
DISPLAY("Error: could not read %d bytes\n", FILE_CHUNK_SIZE);
ret = 1;
goto cleanup;
}
{
size_t const compressedSize = ZSTD_compress(dst, dstSize, src, readSize, 6);
if (ZSTD_isError(compressedSize)) {
DISPLAY("Error: something went wrong during compression\n");
ret = 1;
goto cleanup;
}
{
size_t const writeSize = fwrite(dst, 1, compressedSize, dstFile);
if (writeSize != compressedSize) {
DISPLAY("Error: could not write compressed data to file\n");
ret = 1;
goto cleanup;
}
}
}
if (feof(srcFile)) {
/* reached end of file */
break;
}
}
/* file compression completed */
{
int const error = fclose(srcFile);
if (ret != 0) {
DISPLAY("Error: could not close the file\n");
ret = error;
goto cleanup;
}
}
cleanup:
if (src != NULL) free(src);
if (dst != NULL) free(dst);
return ret;
}