Create virtual codec APIs so chrome/fuzzers can link separately

The one step to make an actual concrete class is conditionalized
in fpdfview and is unconditional in the fuzzer.

Also replace the clumsy C-style callbacks with a delegate
interface as long as we are making new interfaces.

Change-Id: I733a437483ce5e0c34211cfbbda05105336f55b5
Reviewed-on: https://pdfium-review.googlesource.com/2887
Commit-Queue: Tom Sepez <tsepez@chromium.org>
Commit-Queue: dsinclair <dsinclair@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>

1 files changed, 47 insertions, 0 deletions

diff --git a/core/fxcodec/codec/icodec_pngmodule.h b/core/fxcodec/codec/icodec_pngmodule.h
new file mode 100644
index 0000000000..63e61fe5b5
--- /dev/null
+++ b/core/fxcodec/codec/icodec_pngmodule.h
@@ -0,0 +1,47 @@
+// Copyright 2017 PDFium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
+
+#ifndef CORE_FXCODEC_CODEC_ICODEC_PNGMODULE_H_
+#define CORE_FXCODEC_CODEC_ICODEC_PNGMODULE_H_
+
+#include "core/fxcrt/fx_system.h"
+
+class CFX_DIBAttribute;
+struct FXPNG_Context;
+
+// Virtual interface to avoid linking in a concrete implementation
+// if we do not enable this codec.
+class ICodec_PngModule {
+ public:
+  class Delegate {
+   public:
+    virtual bool PngReadHeader(int width,
+                               int height,
+                               int bpc,
+                               int pass,
+                               int* color_type,
+                               double* gamma) = 0;
+    virtual bool PngAskScanlineBuf(int line, uint8_t*& src_buf) = 0;
+    virtual void PngFillScanlineBufCompleted(int pass, int line) = 0;
+  };
+
+  virtual ~ICodec_PngModule() {}
+
+  virtual FXPNG_Context* Start() = 0;
+  virtual void Finish(FXPNG_Context* pContext) = 0;
+  virtual bool Input(FXPNG_Context* pContext,
+                     const uint8_t* src_buf,
+                     uint32_t src_size,
+                     CFX_DIBAttribute* pAttribute) = 0;
+
+  Delegate* GetDelegate() const { return m_pDelegate; }
+  void SetDelegate(Delegate* delegate) { m_pDelegate = delegate; }
+
+ protected:
+  Delegate* m_pDelegate;
+};
+
+#endif  // CORE_FXCODEC_CODEC_ICODEC_PNGMODULE_H_