Updates to skimage tool to use it for testing.

src/images/SkImageDecoder_libjpeg.cpp

 
 /*
  * Copyright 2007 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "SkImageDecoder.h"
@@ skipping 103 matching lines @@
     virtual Format getFormat() const {
         return kJPEG_Format;
     }
 
 protected:
 #ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK
     virtual bool onBuildTileIndex(SkStream *stream, int *width, int *height) SK_OVERRIDE;
     virtual bool onDecodeRegion(SkBitmap* bitmap, const SkIRect& rect) SK_OVERRIDE;
 #endif
     virtual bool onDecode(SkStream* stream, SkBitmap* bm, Mode) SK_OVERRIDE;
+    virtual Format onGetFormat(SkStream*) const SK_OVERRIDE;
 
 private:
     SkJPEGImageIndex* fImageIndex;
     int fImageWidth;
     int fImageHeight;
 
     typedef SkImageDecoder INHERITED;
 };
 
 //////////////////////////////////////////////////////////////////////////
@@ skipping 852 matching lines @@
             srcRow = (const void*)((const char*)srcRow + bm.rowBytes());
         }
 
         jpeg_finish_compress(&cinfo);
         jpeg_destroy_compress(&cinfo);
 
         return true;
     }
 };
 
-///////////////////////////////////////////////////////////////////////////////
-DEFINE_DECODER_CREATOR(JPEGImageDecoder);
-DEFINE_ENCODER_CREATOR(JPEGImageEncoder);
-///////////////////////////////////////////////////////////////////////////////
-
-#include "SkTRegistry.h"
-
-static SkImageDecoder* sk_libjpeg_dfactory(SkStream* stream) {
+static bool is_jpeg(SkStream* stream) {
     static const unsigned char gHeader[] = { 0xFF, 0xD8, 0xFF };
     static const size_t HEADER_SIZE = sizeof(gHeader);
 
     char buffer[HEADER_SIZE];
     size_t len = stream->read(buffer, HEADER_SIZE);
 
     if (len != HEADER_SIZE) {
-        return NULL;   // can't read enough
+        return false;   // can't read enough
     }
     if (memcmp(buffer, gHeader, HEADER_SIZE)) {
-        return NULL;
+        return false;
     }
-    return SkNEW(SkJPEGImageDecoder);
+    return true;
+}
+
+SkImageDecoder::Format SkJPEGImageDecoder::onGetFormat(SkStream* stream) const {
+    if (is_jpeg(stream)) {
+        return kJPEG_Format;
+    }
+    return kUnknown_Format;
+}
+
+///////////////////////////////////////////////////////////////////////////////
+DEFINE_DECODER_CREATOR(JPEGImageDecoder);
+DEFINE_ENCODER_CREATOR(JPEGImageEncoder);
+///////////////////////////////////////////////////////////////////////////////
+
+#include "SkTRegistry.h"
+
+static SkImageDecoder* sk_libjpeg_dfactory(SkStream* stream) {
+    if (is_jpeg(stream)) {
+        return SkNEW(SkJPEGImageDecoder);
+    }
+    return NULL;
 }
 
 static SkImageEncoder* sk_libjpeg_efactory(SkImageEncoder::Type t) {
     return (SkImageEncoder::kJPEG_Type == t) ? SkNEW(SkJPEGImageEncoder) : NULL;
 }
 
 
 static SkTRegistry<SkImageDecoder*, SkStream*> gDReg(sk_libjpeg_dfactory);
 static SkTRegistry<SkImageEncoder*, SkImageEncoder::Type> gEReg(sk_libjpeg_efactory);