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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 18:24:20 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 18:24:20 +0000
commit483eb2f56657e8e7f419ab1a4fab8dce9ade8609 (patch)
treee5d88d25d870d5dedacb6bbdbe2a966086a0a5cf /src/zstd/examples/dictionary_decompression.c
parentInitial commit. (diff)
downloadceph-upstream.tar.xz
ceph-upstream.zip
Adding upstream version 14.2.21.upstream/14.2.21upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/zstd/examples/dictionary_decompression.c')
-rw-r--r--src/zstd/examples/dictionary_decompression.c131
1 files changed, 131 insertions, 0 deletions
diff --git a/src/zstd/examples/dictionary_decompression.c b/src/zstd/examples/dictionary_decompression.c
new file mode 100644
index 00000000..07e6e24c
--- /dev/null
+++ b/src/zstd/examples/dictionary_decompression.c
@@ -0,0 +1,131 @@
+/*
+ * 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, exit
+#include <stdio.h> // printf
+#include <string.h> // strerror
+#include <errno.h> // errno
+#include <sys/stat.h> // stat
+#define ZSTD_STATIC_LINKING_ONLY // ZSTD_findDecompressedSize
+#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("malloc");
+ exit(3);
+}
+
+static void* loadFile_orDie(const char* fileName, size_t* size)
+{
+ off_t const buffSize = fsize_orDie(fileName);
+ 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(4);
+ }
+ fclose(inFile);
+ *size = buffSize;
+ return buffer;
+}
+
+/* createDict() :
+ `dictFileName` is supposed to have been created using `zstd --train` */
+static ZSTD_DDict* createDict_orDie(const char* dictFileName)
+{
+ size_t dictSize;
+ printf("loading dictionary %s \n", dictFileName);
+ void* const dictBuffer = loadFile_orDie(dictFileName, &dictSize);
+ ZSTD_DDict* const ddict = ZSTD_createDDict(dictBuffer, dictSize);
+ if (ddict==NULL) { fprintf(stderr, "ZSTD_createDDict error \n"); exit(5); }
+ free(dictBuffer);
+ return ddict;
+}
+
+
+static void decompress(const char* fname, const ZSTD_DDict* ddict)
+{
+ size_t cSize;
+ void* const cBuff = loadFile_orDie(fname, &cSize);
+ unsigned long long const rSize = ZSTD_findDecompressedSize(cBuff, cSize);
+ if (rSize==ZSTD_CONTENTSIZE_ERROR) {
+ fprintf(stderr, "%s : it was not compressed by zstd.\n", fname);
+ exit(5);
+ } else if (rSize==ZSTD_CONTENTSIZE_UNKNOWN) {
+ fprintf(stderr, "%s : original size unknown \n", fname);
+ exit(6);
+ }
+
+ void* const rBuff = malloc_orDie((size_t)rSize);
+
+ ZSTD_DCtx* const dctx = ZSTD_createDCtx();
+ if (dctx==NULL) { fprintf(stderr, "ZSTD_createDCtx() error \n"); exit(10); }
+ size_t const dSize = ZSTD_decompress_usingDDict(dctx, rBuff, rSize, cBuff, cSize, ddict);
+ if (dSize != rSize) {
+ fprintf(stderr, "error decoding %s : %s \n", fname, ZSTD_getErrorName(dSize));
+ exit(7);
+ }
+
+ /* success */
+ printf("%25s : %6u -> %7u \n", fname, (unsigned)cSize, (unsigned)rSize);
+
+ ZSTD_freeDCtx(dctx);
+ free(rBuff);
+ free(cBuff);
+}
+
+
+int main(int argc, const char** argv)
+{
+ const char* const exeName = argv[0];
+
+ if (argc<3) {
+ printf("wrong arguments\n");
+ printf("usage:\n");
+ printf("%s [FILES] dictionary\n", exeName);
+ return 1;
+ }
+
+ /* load dictionary only once */
+ const char* const dictName = argv[argc-1];
+ ZSTD_DDict* const dictPtr = createDict_orDie(dictName);
+
+ int u;
+ for (u=1; u<argc-1; u++) decompress(argv[u], dictPtr);
+
+ ZSTD_freeDDict(dictPtr);
+ printf("All %u files correctly decoded (in memory) \n", argc-2);
+ return 0;
+}