added streaming_decompression example

examples/.gitignore

@@ -4,6 +4,7 @@ simple_decompression
 dictionary_compression
 dictionary_decompression
 streaming_compression
+streaming_decompression
 
 #test artefact
 tmp*

examples/Makefile

@@ -32,7 +32,7 @@ default: all
 
 all: simple_compression simple_decompression \
 	dictionary_compression dictionary_decompression \
-	streaming_compression
+	streaming_compression streaming_decompression
 
 simple_compression : simple_compression.c
 	$(CC) $(CPPFLAGS) $(CFLAGS) $^ $(LDFLAGS) -o $@
@@ -49,11 +49,14 @@ dictionary_decompression : dictionary_decompression.c
 streaming_compression : streaming_compression.c
 	$(CC) $(CPPFLAGS) $(CFLAGS) $^ $(LDFLAGS) -o $@
 
+streaming_decompression : streaming_decompression.c
+	$(CC) $(CPPFLAGS) $(CFLAGS) $^ $(LDFLAGS) -o $@
+
 clean:
 	@rm -f core *.o tmp* result* *.zst \
         simple_compression simple_decompression \
 		dictionary_compression dictionary_decompression \
-		streaming_compression
+		streaming_compression streaming_decompression
 	@echo Cleaning completed
 
 test: all
@@ -61,8 +64,10 @@ test: all
 	@echo starting simple compression
 	./simple_compression tmp
 	./simple_decompression tmp.zst
+	./streaming_decompression tmp.zst
 	@echo starting streaming compression
 	./streaming_compression tmp
+	./streaming_decompression tmp.zst
 	@echo starting dictionary compression
 	./dictionary_compression tmp README.md
 	./dictionary_decompression tmp.zst README.md

examples/streaming_compression.c

@@ -24,7 +24,7 @@
 */
 
 #include <stdlib.h>    // malloc, exit
-#include <stdio.h>     // fprintf, perror
+#include <stdio.h>     // fprintf, perror, feof
 #include <string.h>    // strerror
 #include <errno.h>     // errno
 #define ZSTD_STATIC_LINKING_ONLY  // streaming API defined as "experimental" for the time being
@@ -36,7 +36,7 @@ static void* malloc_orDie(size_t size)
     void* const buff = malloc(size);
     if (buff) return buff;
     /* error */
-    perror(NULL);
+    perror("malloc:");
     exit(1);
 }
 

examples/streaming_decompression.c

@@ -0,0 +1,116 @@
+/*
+  Streaming compression
+  Educational program using zstd library
+  Copyright (C) Yann Collet 2016
+
+  GPL v2 License
+
+  This program is free software; you can redistribute it and/or modify
+  it under the terms of the GNU General Public License as published by
+  the Free Software Foundation; either version 2 of the License, or
+  (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License along
+  with this program; if not, write to the Free Software Foundation, Inc.,
+  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+
+  You can contact the author at :
+  - zstd homepage : http://www.zstd.net/
+*/
+
+#include <stdlib.h>    // malloc, exit
+#include <stdio.h>     // fprintf, perror, feof
+#include <string.h>    // strerror
+#include <errno.h>     // errno
+#define ZSTD_STATIC_LINKING_ONLY  // streaming API defined as "experimental" for the time being
+#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 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);
+    size_t const buffOutSize = ZSTD_DStreamOutSize();;
+    void*  const buffOut = malloc_orDie(buffOutSize);
+    size_t read, toRead = buffInSize;
+
+    ZSTD_DStream* const dstream = ZSTD_createDStream();
+    if (dstream==NULL) { fprintf(stderr, "ZSTD_createDStream() error \n"); exit(10); }
+    size_t const initResult = ZSTD_initDStream(dstream);
+    if (ZSTD_isError(initResult)) { fprintf(stderr, "ZSTD_initDStream() error \n"); exit(11); }
+
+    while( (read = fread_orDie(buffIn, toRead, fin)) ) {
+        ZSTD_rCursor cursin = { buffIn, read };
+        while (cursin.size) {
+            ZSTD_wCursor cursout = { buffOut, buffOutSize, 0 };
+            toRead = ZSTD_decompressStream(dstream, &cursout , &cursin);
+            /* note : data is just "sinked" into buffOut */
+        }
+    }
+
+    fclose_orDie(fin);
+    free(buffIn);
+    free(buffOut);
+}
+
+
+int main(int argc, const char** argv)
+{
+    const char* const exeName = argv[0];
+    const char* const inFilename = argv[1];
+
+    if (argc!=2) {
+        printf("wrong arguments\n");
+        printf("usage:\n");
+        printf("%s FILE\n", exeName);
+        return 1;
+    }
+
+    decompressFile_orDie(inFilename);
+    printf("%s correctly decoded (in memory). \n", inFilename);
+
+    return 0;
+}