Merge pull request #866 from sandyharvie/dev

Fix issue #865

3 files changed, 22 insertions, 1 deletions

diff --git a/lib/lz4frame.c b/lib/lz4frame.c
index c9f630d..5d716ea 100644
--- a/lib/lz4frame.c
+++ b/lib/lz4frame.c
@@ -725,6 +725,9 @@ size_t LZ4F_compressBegin(LZ4F_cctx* cctxPtr,
  */
 size_t LZ4F_compressBound(size_t srcSize, const LZ4F_preferences_t* preferencesPtr)
 {
+    if (preferencesPtr && preferencesPtr->autoFlush) {
+        return LZ4F_compressBound_internal(srcSize, preferencesPtr, 0);
+    }
     return LZ4F_compressBound_internal(srcSize, preferencesPtr, (size_t)-1);
 }
 
diff --git a/lib/lz4frame.h b/lib/lz4frame.h
index 391e484..87b0b2a 100644
--- a/lib/lz4frame.h
+++ b/lib/lz4frame.h
@@ -284,7 +284,7 @@ LZ4FLIB_API size_t LZ4F_compressBegin(LZ4F_cctx* cctx,
  * @return is always the same for a srcSize and prefsPtr.
  *  prefsPtr is optional : when NULL is provided, preferences will be set to cover worst case scenario.
  *  tech details :
- * @return includes the possibility that internal buffer might already be filled by up to (blockSize-1) bytes.
+ * @return if automatic flushing is not enabled, includes the possibility that internal buffer might already be filled by up to (blockSize-1) bytes.
  *  It also includes frame footer (ending + checksum), since it might be generated by LZ4F_compressEnd().
  * @return doesn't include frame header, as it was already generated by LZ4F_compressBegin().
  */
diff --git a/tests/frametest.c b/tests/frametest.c
index 1b932e4..f891530 100644
--- a/tests/frametest.c
+++ b/tests/frametest.c
@@ -200,6 +200,24 @@ int basicTests(U32 seed, double compressibility)
         DISPLAYLEVEL(3, " %u \n", (U32)cBound);
     }
 
+    /* LZ4F_compressBound() : special case : automatic flushing enabled */
+    DISPLAYLEVEL(3, "LZ4F_compressBound(1 KB, autoFlush=1) = ");
+    {   size_t cBound;
+        LZ4F_preferences_t autoFlushPrefs;
+        memset(&autoFlushPrefs, 0, sizeof(autoFlushPrefs));
+        autoFlushPrefs.autoFlush = 1;
+        cBound = LZ4F_compressBound(1 KB, &autoFlushPrefs);
+        if (cBound > 64 KB) goto _output_error;
+        DISPLAYLEVEL(3, " %u \n", (U32)cBound);
+    }
+
+    /* LZ4F_compressBound() : special case : automatic flushing disabled */
+    DISPLAYLEVEL(3, "LZ4F_compressBound(1 KB, autoFlush=0) = ");
+    {   size_t const cBound = LZ4F_compressBound(1 KB, &prefs);
+        if (cBound < 64 KB) goto _output_error;
+        DISPLAYLEVEL(3, " %u \n", (U32)cBound);
+    }
+
     /* Special case : null-content frame */
     testSize = 0;
     DISPLAYLEVEL(3, "LZ4F_compressFrame, compress null content : ");