1 files changed, 73 insertions, 0 deletions
diff --git a/core/fxcodec/codec/ccodec_scanlinedecoder.cpp b/core/fxcodec/codec/ccodec_scanlinedecoder.cpp
new file mode 100644
index 0000000000..55b9a2a87d
--- /dev/null
+++ b/core/fxcodec/codec/ccodec_scanlinedecoder.cpp
@@ -0,0 +1,73 @@
+// 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
+
+#include "core/fxcodec/codec/ccodec_scanlinedecoder.h"
+
+#include "core/fxcrt/ifx_pauseindicator.h"
+
+CCodec_ScanlineDecoder::CCodec_ScanlineDecoder()
+    : CCodec_ScanlineDecoder(0, 0, 0, 0, 0, 0, 0) {}
+
+CCodec_ScanlineDecoder::CCodec_ScanlineDecoder(int nOrigWidth,
+                                               int nOrigHeight,
+                                               int nOutputWidth,
+                                               int nOutputHeight,
+                                               int nComps,
+                                               int nBpc,
+                                               uint32_t nPitch)
+    : m_OrigWidth(nOrigWidth),
+      m_OrigHeight(nOrigHeight),
+      m_OutputWidth(nOutputWidth),
+      m_OutputHeight(nOutputHeight),
+      m_nComps(nComps),
+      m_bpc(nBpc),
+      m_Pitch(nPitch),
+      m_NextLine(-1),
+      m_pLastScanline(nullptr) {}
+
+CCodec_ScanlineDecoder::~CCodec_ScanlineDecoder() {}
+
+const uint8_t* CCodec_ScanlineDecoder::GetScanline(int line) {
+  if (m_NextLine == line + 1)
+    return m_pLastScanline;
+
+  if (m_NextLine < 0 || m_NextLine > line) {
+    if (!v_Rewind())
+      return nullptr;
+    m_NextLine = 0;
+  }
+  while (m_NextLine < line) {
+    ReadNextLine();
+    m_NextLine++;
+  }
+  m_pLastScanline = ReadNextLine();
+  m_NextLine++;
+  return m_pLastScanline;
+}
+
+bool CCodec_ScanlineDecoder::SkipToScanline(int line,
+                                            IFX_PauseIndicator* pPause) {
+  if (m_NextLine == line || m_NextLine == line + 1)
+    return false;
+
+  if (m_NextLine < 0 || m_NextLine > line) {
+    v_Rewind();
+    m_NextLine = 0;
+  }
+  m_pLastScanline = nullptr;
+  while (m_NextLine < line) {
+    m_pLastScanline = ReadNextLine();
+    m_NextLine++;
+    if (pPause && pPause->NeedToPauseNow()) {
+      return true;
+    }
+  }
+  return false;
+}
+
+uint8_t* CCodec_ScanlineDecoder::ReadNextLine() {
+  return v_GetNextLine();
+}