1 files changed, 116 insertions, 0 deletions
diff --git a/src/zstd/examples/streaming_decompression.c b/src/zstd/examples/streaming_decompression.c
new file mode 100644
index 00000000..504a5e31
--- /dev/null
+++ b/src/zstd/examples/streaming_decompression.c
@@ -0,0 +1,116 @@
+/*
+ * 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>     // fprintf, perror, feof
+#include <string.h>    // strerror
+#include <errno.h>     // errno
+#include <zstd.h>      // presumes zstd library is installed
+
+
+static void* malloc_orDie(size_t size)
+{
+    void* const buff = malloc(size);
+    if (buff) return buff;
+    /* error */
+    perror("malloc:");
+    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(3);
+}
+
+static size_t fread_orDie(void* buffer, size_t sizeToRead, FILE* file)
+{
+    size_t const readSize = fread(buffer, 1, sizeToRead, file);
+    if (readSize == sizeToRead) return readSize;   /* good */
+    if (feof(file)) return readSize;   /* good, reached end of file */
+    /* error */
+    perror("fread");
+    exit(4);
+}
+
+static size_t fwrite_orDie(const void* buffer, size_t sizeToWrite, FILE* file)
+{
+    size_t const writtenSize = fwrite(buffer, 1, sizeToWrite, file);
+    if (writtenSize == sizeToWrite) return sizeToWrite;   /* good */
+    /* error */
+    perror("fwrite");
+    exit(5);
+}
+
+static size_t fclose_orDie(FILE* file)
+{
+    if (!fclose(file)) return 0;
+    /* error */
+    perror("fclose");
+    exit(6);
+}
+
+
+static void decompressFile_orDie(const char* fname)
+{
+    FILE* const fin  = fopen_orDie(fname, "rb");
+    size_t const buffInSize = ZSTD_DStreamInSize();
+    void*  const buffIn  = malloc_orDie(buffInSize);
+    FILE* const fout = stdout;
+    size_t const buffOutSize = ZSTD_DStreamOutSize();  /* Guarantee to successfully flush at least one complete compressed block in all circumstances. */
+    void*  const buffOut = malloc_orDie(buffOutSize);
+
+    ZSTD_DStream* const dstream = ZSTD_createDStream();
+    if (dstream==NULL) { fprintf(stderr, "ZSTD_createDStream() error \n"); exit(10); }
+
+    /* In more complex scenarios, a file may consist of multiple appended frames (ex : pzstd).
+    *  The following example decompresses only the first frame.
+    *  It is compatible with other provided streaming examples */
+    size_t const initResult = ZSTD_initDStream(dstream);
+    if (ZSTD_isError(initResult)) { fprintf(stderr, "ZSTD_initDStream() error : %s \n", ZSTD_getErrorName(initResult)); exit(11); }
+    size_t read, toRead = initResult;
+    while ( (read = fread_orDie(buffIn, toRead, fin)) ) {
+        ZSTD_inBuffer input = { buffIn, read, 0 };
+        while (input.pos < input.size) {
+            ZSTD_outBuffer output = { buffOut, buffOutSize, 0 };
+            toRead = ZSTD_decompressStream(dstream, &output , &input);  /* toRead : size of next compressed block */
+            if (ZSTD_isError(toRead)) { fprintf(stderr, "ZSTD_decompressStream() error : %s \n", ZSTD_getErrorName(toRead)); exit(12); }
+            fwrite_orDie(buffOut, output.pos, fout);
+        }
+    }
+
+    ZSTD_freeDStream(dstream);
+    fclose_orDie(fin);
+    fclose_orDie(fout);
+    free(buffIn);
+    free(buffOut);
+}
+
+
+int main(int argc, const char** argv)
+{
+    const char* const exeName = argv[0];
+
+    if (argc!=2) {
+        fprintf(stderr, "wrong arguments\n");
+        fprintf(stderr, "usage:\n");
+        fprintf(stderr, "%s FILE\n", exeName);
+        return 1;
+    }
+
+    const char* const inFilename = argv[1];
+
+    decompressFile_orDie(inFilename);
+    return 0;
+}