Change SkImageDecoders to take an SkStreamRewindable.

src/images/SkImageDecoder_libgif.cpp

 
 /*
  * Copyright 2006 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"
 #include "SkColor.h"
 #include "SkColorPriv.h"
 #include "SkStream.h"
 #include "SkTemplates.h"
 #include "SkPackBits.h"
 
 #include "gif_lib.h"
 
 class SkGIFImageDecoder : public SkImageDecoder {
 public:
     virtual Format getFormat() const SK_OVERRIDE {
         return kGIF_Format;
     }
 
 protected:
-    virtual bool onDecode(SkStream* stream, SkBitmap* bm, Mode mode) SK_OVERRIDE;
+    virtual bool onDecode(SkStreamRewindable* stream, SkBitmap* bm, Mode mode) SK_OVERRIDE;
 
 private:
     typedef SkImageDecoder INHERITED;
 };
 
 static const uint8_t gStartingIterlaceYValue[] = {
     0, 4, 2, 1
 };
 static const uint8_t gDeltaIterlaceYValue[] = {
     8, 8, 4, 2
@@ skipping 49 matching lines @@
     int fCurrY;
     int fDeltaY;
     const uint8_t* fStartYPtr;
     const uint8_t* fDeltaYPtr;
 };
 
 ///////////////////////////////////////////////////////////////////////////////
 
 static int DecodeCallBackProc(GifFileType* fileType, GifByteType* out,
                               int size) {
-    SkStream* stream = (SkStream*) fileType->UserData;
+    SkStreamRewindable* stream = (SkStreamRewindable*) fileType->UserData;
     return (int) stream->read(out, size);
 }
 
 void CheckFreeExtension(SavedImage* Image) {
     if (Image->ExtensionBlocks) {
 #if GIFLIB_MAJOR < 5
         FreeExtension(Image);
 #else
         GifFreeExtensions(&Image->ExtensionBlockCount, &Image->ExtensionBlocks);
 #endif
@@ skipping 40 matching lines @@
 
 static bool error_return(GifFileType* gif, const SkBitmap& bm,
                          const char msg[]) {
 #if 0
     SkDebugf("libgif error <%s> bitmap [%d %d] pixels %p colortable %p\n",
              msg, bm.width(), bm.height(), bm.getPixels(), bm.getColorTable());
 #endif
     return false;
 }
 
-bool SkGIFImageDecoder::onDecode(SkStream* sk_stream, SkBitmap* bm, Mode mode) {
+bool SkGIFImageDecoder::onDecode(SkStreamRewindable* sk_stream, SkBitmap* bm, Mode mode) {
 #if GIFLIB_MAJOR < 5
     GifFileType* gif = DGifOpen(sk_stream, DecodeCallBackProc);
 #else
     GifFileType* gif = DGifOpen(sk_stream, DecodeCallBackProc, NULL);
 #endif
     if (NULL == gif) {
         return error_return(gif, *bm, "DGifOpen");
     }
 
     SkAutoTCallIProc<GifFileType, DGifCloseFile> acp(gif);
@@ skipping 181 matching lines @@
     } while (recType != TERMINATE_RECORD_TYPE);
 
 DONE:
     return true;
 }
 
 ///////////////////////////////////////////////////////////////////////////////
 DEFINE_DECODER_CREATOR(GIFImageDecoder);
 ///////////////////////////////////////////////////////////////////////////////
 
-static bool is_gif(SkStream* stream) {
+static bool is_gif(SkStreamRewindable* stream) {
     char buf[GIF_STAMP_LEN];
     if (stream->read(buf, GIF_STAMP_LEN) == GIF_STAMP_LEN) {
         if (memcmp(GIF_STAMP,   buf, GIF_STAMP_LEN) == 0 ||
                 memcmp(GIF87_STAMP, buf, GIF_STAMP_LEN) == 0 ||
                 memcmp(GIF89_STAMP, buf, GIF_STAMP_LEN) == 0) {
             return true;
         }
     }
     return false;
 }
 
 #include "SkTRegistry.h"
 
-static SkImageDecoder* sk_libgif_dfactory(SkStream* stream) {
+static SkImageDecoder* sk_libgif_dfactory(SkStreamRewindable* stream) {
     if (is_gif(stream)) {
         return SkNEW(SkGIFImageDecoder);
     }
     return NULL;
 }
 
-static SkTRegistry<SkImageDecoder*, SkStream*> gReg(sk_libgif_dfactory);
+static SkTRegistry<SkImageDecoder*, SkStreamRewindable*> gReg(sk_libgif_dfactory);
 
-static SkImageDecoder::Format get_format_gif(SkStream* stream) {
+static SkImageDecoder::Format get_format_gif(SkStreamRewindable* stream) {
     if (is_gif(stream)) {
         return SkImageDecoder::kGIF_Format;
     }
     return SkImageDecoder::kUnknown_Format;
 }
 
-static SkTRegistry<SkImageDecoder::Format, SkStream*> gFormatReg(get_format_gif);
+static SkTRegistry<SkImageDecoder::Format, SkStreamRewindable*> gFormatReg(get_format_gif);