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-rw-r--r--src/zstd/examples/simple_compression.c135
1 files changed, 135 insertions, 0 deletions
diff --git a/src/zstd/examples/simple_compression.c b/src/zstd/examples/simple_compression.c
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+++ b/src/zstd/examples/simple_compression.c
@@ -0,0 +1,135 @@
+/*
+ * Copyright (c) 2016-present, 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 <stdlib.h> // malloc, free, exit
+#include <stdio.h> // fprintf, perror, fopen, etc.
+#include <string.h> // strlen, strcat, memset, strerror
+#include <errno.h> // errno
+#include <sys/stat.h> // stat
+#include <zstd.h> // presumes zstd library is installed
+
+
+static off_t fsize_orDie(const char *filename)
+{
+ struct stat st;
+ if (stat(filename, &st) == 0) return st.st_size;
+ /* error */
+ perror(filename);
+ exit(1);
+}
+
+static FILE* fopen_orDie(const char *filename, const char *instruction)
+{
+ FILE* const inFile = fopen(filename, instruction);
+ if (inFile) return inFile;
+ /* error */
+ perror(filename);
+ exit(2);
+}
+
+static void* malloc_orDie(size_t size)
+{
+ void* const buff = malloc(size);
+ if (buff) return buff;
+ /* error */
+ perror(NULL);
+ exit(3);
+}
+
+static void* loadFile_orDie(const char* fileName, size_t* size)
+{
+ off_t const fileSize = fsize_orDie(fileName);
+ size_t const buffSize = (size_t)fileSize;
+ if ((off_t)buffSize < fileSize) { /* narrowcast overflow */
+ fprintf(stderr, "%s : filesize too large \n", fileName);
+ exit(4);
+ }
+ FILE* const inFile = fopen_orDie(fileName, "rb");
+ void* const buffer = malloc_orDie(buffSize);
+ size_t const readSize = fread(buffer, 1, buffSize, inFile);
+ if (readSize != (size_t)buffSize) {
+ fprintf(stderr, "fread: %s : %s \n", fileName, strerror(errno));
+ exit(5);
+ }
+ fclose(inFile); /* can't fail, read only */
+ *size = buffSize;
+ return buffer;
+}
+
+
+static void saveFile_orDie(const char* fileName, const void* buff, size_t buffSize)
+{
+ FILE* const oFile = fopen_orDie(fileName, "wb");
+ size_t const wSize = fwrite(buff, 1, buffSize, oFile);
+ if (wSize != (size_t)buffSize) {
+ fprintf(stderr, "fwrite: %s : %s \n", fileName, strerror(errno));
+ exit(6);
+ }
+ if (fclose(oFile)) {
+ perror(fileName);
+ exit(7);
+ }
+}
+
+
+static void compress_orDie(const char* fname, const char* oname)
+{
+ size_t fSize;
+ void* const fBuff = loadFile_orDie(fname, &fSize);
+ size_t const cBuffSize = ZSTD_compressBound(fSize);
+ void* const cBuff = malloc_orDie(cBuffSize);
+
+ size_t const cSize = ZSTD_compress(cBuff, cBuffSize, fBuff, fSize, 1);
+ if (ZSTD_isError(cSize)) {
+ fprintf(stderr, "error compressing %s : %s \n", fname, ZSTD_getErrorName(cSize));
+ exit(8);
+ }
+
+ saveFile_orDie(oname, cBuff, cSize);
+
+ /* success */
+ printf("%25s : %6u -> %7u - %s \n", fname, (unsigned)fSize, (unsigned)cSize, oname);
+
+ free(fBuff);
+ free(cBuff);
+}
+
+
+static char* createOutFilename_orDie(const char* filename)
+{
+ size_t const inL = strlen(filename);
+ size_t const outL = inL + 5;
+ void* const outSpace = malloc_orDie(outL);
+ memset(outSpace, 0, outL);
+ strcat(outSpace, filename);
+ strcat(outSpace, ".zst");
+ return (char*)outSpace;
+}
+
+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;
+ }
+
+ const char* const inFilename = argv[1];
+
+ char* const outFilename = createOutFilename_orDie(inFilename);
+ compress_orDie(inFilename, outFilename);
+ free(outFilename);
+ return 0;
+}