Modified : streaming API (fast compression)

3 files changed, 45 insertions, 23 deletions

diff --git a/lz4.c b/lz4.c
index 1a864e9..5ce6c71 100644
--- a/lz4.c
+++ b/lz4.c
@@ -684,10 +684,21 @@ int LZ4_compress_limitedOutput(const char* source, char* dest, int inputSize, in
    Experimental : Streaming functions
 *****************************************/
 
-void* LZ4_createStream()
+/*
+ * LZ4_initStream
+ * Use this function once, to init a newly allocated LZ4_stream_t structure
+ * Return : 1 if OK, 0 if error
+ */
+void LZ4_resetStream (LZ4_stream_t* LZ4_stream)
+{
+    MEM_INIT(LZ4_stream, 0, sizeof(LZ4_stream_t));
+}
+
+
+void* LZ4_createStream(void)
 {
     void* lz4s = ALLOCATOR(4, LZ4_STREAMSIZE_U32);
-    MEM_INIT(lz4s, 0, LZ4_STREAMSIZE);
+    LZ4_resetStream(lz4s);
     return lz4s;
 }
 
@@ -698,15 +709,15 @@ int LZ4_free (void* LZ4_stream)
 }
 
 
-int LZ4_loadDict (void* LZ4_dict, const char* dictionary, int dictSize)
+int LZ4_loadDict (LZ4_stream_t* LZ4_dict, const char* dictionary, int dictSize)
 {
     LZ4_stream_t_internal* dict = (LZ4_stream_t_internal*) LZ4_dict;
     const BYTE* p = (const BYTE*)dictionary;
     const BYTE* const dictEnd = p + dictSize;
     const BYTE* base;
 
-    LZ4_STATIC_ASSERT(LZ4_STREAMSIZE >= sizeof(LZ4_stream_t_internal));      /* A compilation error here means LZ4_STREAMSIZE is not large enough */
-    if (dict->initCheck) MEM_INIT(dict, 0, sizeof(LZ4_stream_t_internal));   /* Uninitialized structure detected */
+    LZ4_STATIC_ASSERT(LZ4_STREAMSIZE >= sizeof(LZ4_stream_t_internal));    /* A compilation error here means LZ4_STREAMSIZE is not large enough */
+    if (dict->initCheck) LZ4_resetStream(LZ4_dict);                         /* Uninitialized structure detected */
 
     if (dictSize < MINMATCH)
     {
@@ -803,12 +814,12 @@ FORCE_INLINE int LZ4_compress_continue_generic (void* LZ4_stream, const char* so
 }
 
 
-int LZ4_compress_continue (void* LZ4_stream, const char* source, char* dest, int inputSize)
+int LZ4_compress_continue (LZ4_stream_t* LZ4_stream, const char* source, char* dest, int inputSize)
 {
     return LZ4_compress_continue_generic(LZ4_stream, source, dest, inputSize, 0, notLimited);
 }
 
-int LZ4_compress_limitedOutput_continue (void* LZ4_stream, const char* source, char* dest, int inputSize, int maxOutputSize)
+int LZ4_compress_limitedOutput_continue (LZ4_stream_t* LZ4_stream, const char* source, char* dest, int inputSize, int maxOutputSize)
 {
     return LZ4_compress_continue_generic(LZ4_stream, source, dest, inputSize, maxOutputSize, limitedOutput);
 }
@@ -835,7 +846,7 @@ int LZ4_compress_forceExtDict (LZ4_stream_t* LZ4_dict, const char* source, char*
 }
 
 
-int LZ4_saveDict (void* LZ4_dict, char* safeBuffer, int dictSize)
+int LZ4_saveDict (LZ4_stream_t* LZ4_dict, char* safeBuffer, int dictSize)
 {
     LZ4_stream_t_internal* dict = (LZ4_stream_t_internal*) LZ4_dict;
     const BYTE* previousDictEnd = dict->dictionary + dict->dictSize;
diff --git a/lz4.h b/lz4.h
index 1064fa1..275655d 100644
--- a/lz4.h
+++ b/lz4.h
@@ -166,53 +166,50 @@ int LZ4_decompress_safe_partial (const char* source, char* dest, int compressedS
 /*
  * LZ4_stream_t
  * information structure to track an LZ4 stream.
- * important : set this structure content to zero before first use !
+ * important : init this structure content before first use !
  */
 typedef struct { unsigned int table[LZ4_STREAMSIZE_U32]; } LZ4_stream_t;
 
 /*
- * If you prefer dynamic allocation methods,
- * LZ4_createStream
- * provides a pointer (void*) towards an initialized LZ4_stream_t structure.
- * LZ4_free just frees it.
+ * LZ4_resetStream
+ * Use this function to init a newly allocated LZ4_stream_t structure
+ * You can also reset an existing LZ4_stream_t structure
  */
-void* LZ4_createStream();
-int   LZ4_free (void* LZ4_stream);
-
+void LZ4_resetStream (LZ4_stream_t* LZ4_stream);
 
 /*
  * LZ4_loadDict
  * Use this function to load a static dictionary into LZ4_stream.
  * Any previous data will be forgotten, only 'dictionary' will remain in memory.
- * Loading a size of 0 is allowed (same effect as init).
+ * Loading a size of 0 is allowed.
  * Return : 1 if OK, 0 if error
  */
-int LZ4_loadDict (void* LZ4_stream, const char* dictionary, int dictSize);
+int LZ4_loadDict (LZ4_stream_t* LZ4_stream, const char* dictionary, int dictSize);
 
 /*
  * LZ4_compress_continue
  * Compress data block 'source', using blocks compressed before as dictionary to improve compression ratio
  * Previous data blocks are assumed to still be present at their previous location.
  */
-int LZ4_compress_continue (void* LZ4_stream, const char* source, char* dest, int inputSize);
+int LZ4_compress_continue (LZ4_stream_t* LZ4_stream, const char* source, char* dest, int inputSize);
 
 /*
  * LZ4_compress_limitedOutput_continue
  * Same as before, but also specify a maximum target compressed size (maxOutputSize)
  * If objective cannot be met, compression exits, and returns a zero.
  */
-int LZ4_compress_limitedOutput_continue (void* LZ4_stream, const char* source, char* dest, int inputSize, int maxOutputSize);
+int LZ4_compress_limitedOutput_continue (LZ4_stream_t* LZ4_stream, const char* source, char* dest, int inputSize, int maxOutputSize);
 
 /*
  * LZ4_saveDict
- * If previously compressed data block is not guaranteed to remain at its previous memory location
+ * If previously compressed data block is not guaranteed to remain available at its memory location
  * save it into a safe place (char* safeBuffer)
  * Note : you don't need to call LZ4_loadDict() afterwards,
  *        dictionary is immediately usable, you can therefore call again LZ4_compress_continue()
  * Return : 1 if OK, 0 if error
  * Note : any dictSize > 64 KB will be interpreted as 64KB.
  */
-int LZ4_saveDict (void* LZ4_stream, char* safeBuffer, int dictSize);
+int LZ4_saveDict (LZ4_stream_t* LZ4_stream, char* safeBuffer, int dictSize);
 
 
 /************************************************
@@ -290,6 +287,15 @@ int LZ4_sizeofState(void);
 int LZ4_compress_withState               (void* state, const char* source, char* dest, int inputSize);
 int LZ4_compress_limitedOutput_withState (void* state, const char* source, char* dest, int inputSize, int maxOutputSize);
 
+/*
+ * If you prefer dynamic allocation methods,
+ * LZ4_createStream
+ * provides a pointer (void*) towards an initialized LZ4_stream_t structure.
+ * LZ4_free just frees it.
+ */
+void* LZ4_createStream(void);
+int   LZ4_free (void* LZ4_stream);
+
 /* Obsolete streaming functions; use new streaming interface whenever possible */
 void* LZ4_create (const char* inputBuffer);
 int   LZ4_sizeofStreamState(void);
diff --git a/programs/lz4io.c b/programs/lz4io.c
index 65d1445..7617cff 100644
--- a/programs/lz4io.c
+++ b/programs/lz4io.c
@@ -376,6 +376,11 @@ static int LZ4IO_LZ4_compress_limitedOutput_continue (void* ctx, const char* sou
     return LZ4_compress_limitedOutput_continue(ctx, source, dest, inputSize, maxOutputSize);
 }
 
+static int LZ4IO_LZ4_saveDict (void* LZ4_stream, char* safeBuffer, int dictSize)
+{
+    return LZ4_saveDict ((LZ4_stream_t*) LZ4_stream, safeBuffer, dictSize);
+}
+
 static int LZ4IO_LZ4_slideInputBufferHC (void* ctx, char* buffer, int size)
 {
     (void)size; (void)buffer;
@@ -411,7 +416,7 @@ static int compress_file_blockDependency(char* input_filename, char* output_file
     {
         initFunction = LZ4IO_LZ4_createStream;
         compressionFunction = LZ4IO_LZ4_compress_limitedOutput_continue;
-        nextBlockFunction = LZ4_saveDict;
+        nextBlockFunction = LZ4IO_LZ4_saveDict;
         freeFunction = LZ4_free;
     }
     else