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/*
* Copyright (c) 2016-2020, Yann Collet, Facebook, Inc.
* All rights reserved.
*
* This source code is licensed under both the BSD-style license (found in the
* LICENSE file in the root directory of this source tree) and the GPLv2 (found
* in the COPYING file in the root directory of this source tree).
* You may select, at your option, one of the above-listed licenses.
*/
#include <stdio.h> // printf
#include <stdlib.h> // free
#include <zstd.h> // presumes zstd library is installed
#include "common.h" // Helper functions, CHECK(), and CHECK_ZSTD()
static void decompress(const char* fname)
{
size_t cSize;
void* const cBuff = mallocAndLoadFile_orDie(fname, &cSize);
/* Read the content size from the frame header. For simplicity we require
* that it is always present. By default, zstd will write the content size
* in the header when it is known. If you can't guarantee that the frame
* content size is always written into the header, either use streaming
* decompression, or ZSTD_decompressBound().
*/
unsigned long long const rSize = ZSTD_getFrameContentSize(cBuff, cSize);
CHECK(rSize != ZSTD_CONTENTSIZE_ERROR, "%s: not compressed by zstd!", fname);
CHECK(rSize != ZSTD_CONTENTSIZE_UNKNOWN, "%s: original size unknown!", fname);
void* const rBuff = malloc_orDie((size_t)rSize);
/* Decompress.
* If you are doing many decompressions, you may want to reuse the context
* and use ZSTD_decompressDCtx(). If you want to set advanced parameters,
* use ZSTD_DCtx_setParameter().
*/
size_t const dSize = ZSTD_decompress(rBuff, rSize, cBuff, cSize);
CHECK_ZSTD(dSize);
/* When zstd knows the content size, it will error if it doesn't match. */
CHECK(dSize == rSize, "Impossible because zstd will check this condition!");
/* success */
printf("%25s : %6u -> %7u \n", fname, (unsigned)cSize, (unsigned)rSize);
free(rBuff);
free(cBuff);
}
int main(int argc, const char** argv)
{
const char* const exeName = argv[0];
if (argc!=2) {
printf("wrong arguments\n");
printf("usage:\n");
printf("%s FILE\n", exeName);
return 1;
}
decompress(argv[1]);
printf("%s correctly decoded (in memory). \n", argv[1]);
return 0;
}
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