Move format specific elements out of DetectImageType

Refactoring the big image format switch in DetectImageType to call
separate methods for each image format, instead of having one giant
switch block. This should have no functional changes.

BUG=pdfium:976

Change-Id: I52cc83879da20b33d471420016f6b1eb53993f0b
Reviewed-on: https://pdfium-review.googlesource.com/23130
Commit-Queue: Ryan Harrison <rharrison@chromium.org>
Reviewed-by: dsinclair <dsinclair@chromium.org>

1 files changed, 257 insertions, 232 deletions

diff --git a/core/fxcodec/codec/fx_codec_progress.cpp b/core/fxcodec/codec/fx_codec_progress.cpp
index 36e22e9f85..1b8da15b68 100644
--- a/core/fxcodec/codec/fx_codec_progress.cpp
+++ b/core/fxcodec/codec/fx_codec_progress.cpp
@@ -1002,256 +1002,281 @@ bool CCodec_ProgressiveDecoder::DetectImageType(FXCODEC_IMAGE_TYPE imageType,
   memset(m_pSrcBuf, 0, size);
   m_SrcSize = size;
   switch (imageType) {
-    case FXCODEC_IMAGE_BMP: {
-      CCodec_BmpModule* pBmpModule = m_pCodecMgr->GetBmpModule();
-      if (!pBmpModule) {
-        m_status = FXCODEC_STATUS_ERR_MEMORY;
-        return false;
-      }
+    case FXCODEC_IMAGE_BMP:
+      return BmpDetectImageType(pAttribute, size);
+    case FXCODEC_IMAGE_JPG:
+      return JpegDetectImageType(pAttribute, size);
+    case FXCODEC_IMAGE_PNG:
+      return PngDetectImageType(pAttribute, size);
+    case FXCODEC_IMAGE_GIF:
+      return GifDetectImageType(pAttribute, size);
+    case FXCODEC_IMAGE_TIF:
+      return TifDetectImageType(pAttribute, size);
+    default:
+      m_status = FXCODEC_STATUS_ERR_FORMAT;
+      return false;
+  }
+}
 
-      m_pBmpContext = pBmpModule->Start(this);
-      if (!m_pBmpContext) {
-        m_status = FXCODEC_STATUS_ERR_MEMORY;
-        return false;
-      }
+bool CCodec_ProgressiveDecoder::BmpDetectImageType(CFX_DIBAttribute* pAttribute,
+                                                   uint32_t size) {
+  CCodec_BmpModule* pBmpModule = m_pCodecMgr->GetBmpModule();
+  if (!pBmpModule) {
+    m_status = FXCODEC_STATUS_ERR_MEMORY;
+    return false;
+  }
 
-      if (!m_pFile->ReadBlock(m_pSrcBuf, 0, size)) {
-        m_status = FXCODEC_STATUS_ERR_READ;
-        return false;
-      }
+  m_pBmpContext = pBmpModule->Start(this);
+  if (!m_pBmpContext) {
+    m_status = FXCODEC_STATUS_ERR_MEMORY;
+    return false;
+  }
 
-      m_offSet += size;
-      pBmpModule->Input(m_pBmpContext.get(), m_pSrcBuf, size);
-      std::vector<uint32_t> palette;
-      int32_t readResult = pBmpModule->ReadHeader(
-          m_pBmpContext.get(), &m_SrcWidth, &m_SrcHeight, &m_BmpIsTopBottom,
-          &m_SrcComponents, &m_SrcPaletteNumber, &palette, pAttribute);
-      while (readResult == 2) {
-        FXCODEC_STATUS error_status = FXCODEC_STATUS_ERR_FORMAT;
-        if (!BmpReadMoreData(pBmpModule, error_status)) {
-          m_status = error_status;
-          return false;
-        }
-        readResult = pBmpModule->ReadHeader(
-            m_pBmpContext.get(), &m_SrcWidth, &m_SrcHeight, &m_BmpIsTopBottom,
-            &m_SrcComponents, &m_SrcPaletteNumber, &palette, pAttribute);
-      }
+  if (!m_pFile->ReadBlock(m_pSrcBuf, 0, size)) {
+    m_status = FXCODEC_STATUS_ERR_READ;
+    return false;
+  }
 
-      if (readResult != 1) {
-        m_pBmpContext.reset();
-        m_status = FXCODEC_STATUS_ERR_FORMAT;
-        return false;
-      }
+  m_offSet += size;
+  pBmpModule->Input(m_pBmpContext.get(), m_pSrcBuf, size);
+  std::vector<uint32_t> palette;
+  int32_t readResult = pBmpModule->ReadHeader(
+      m_pBmpContext.get(), &m_SrcWidth, &m_SrcHeight, &m_BmpIsTopBottom,
+      &m_SrcComponents, &m_SrcPaletteNumber, &palette, pAttribute);
+  while (readResult == 2) {
+    FXCODEC_STATUS error_status = FXCODEC_STATUS_ERR_FORMAT;
+    if (!BmpReadMoreData(pBmpModule, error_status)) {
+      m_status = error_status;
+      return false;
+    }
+    readResult = pBmpModule->ReadHeader(
+        m_pBmpContext.get(), &m_SrcWidth, &m_SrcHeight, &m_BmpIsTopBottom,
+        &m_SrcComponents, &m_SrcPaletteNumber, &palette, pAttribute);
+  }
 
-      FXDIB_Format format = FXDIB_Invalid;
-      switch (m_SrcComponents) {
-        case 1:
-          m_SrcFormat = FXCodec_8bppRgb;
-          format = FXDIB_8bppRgb;
-          break;
-        case 3:
-          m_SrcFormat = FXCodec_Rgb;
-          format = FXDIB_Rgb;
-          break;
-        case 4:
-          m_SrcFormat = FXCodec_Rgb32;
-          format = FXDIB_Rgb32;
-          break;
-        default:
-          m_pBmpContext.reset();
-          m_status = FXCODEC_STATUS_ERR_FORMAT;
-          return false;
-          break;
-      }
+  if (readResult != 1) {
+    m_pBmpContext.reset();
+    m_status = FXCODEC_STATUS_ERR_FORMAT;
+    return false;
+  }
 
-      uint32_t pitch = 0;
-      uint32_t neededData = 0;
-      if (!CFX_DIBitmap::CalculatePitchAndSize(m_SrcWidth, m_SrcHeight, format,
-                                               &pitch, &neededData)) {
-        m_pBmpContext.reset();
-        m_status = FXCODEC_STATUS_ERR_FORMAT;
-        return false;
-      }
+  FXDIB_Format format = FXDIB_Invalid;
+  switch (m_SrcComponents) {
+    case 1:
+      m_SrcFormat = FXCodec_8bppRgb;
+      format = FXDIB_8bppRgb;
+      break;
+    case 3:
+      m_SrcFormat = FXCodec_Rgb;
+      format = FXDIB_Rgb;
+      break;
+    case 4:
+      m_SrcFormat = FXCodec_Rgb32;
+      format = FXDIB_Rgb32;
+      break;
+    default:
+      m_pBmpContext.reset();
+      m_status = FXCODEC_STATUS_ERR_FORMAT;
+      return false;
+  }
 
-      uint32_t availableData = m_SrcSize > m_offSet ? m_SrcSize - m_offSet : 0;
-      if (neededData > availableData) {
-        m_pBmpContext.reset();
-        m_status = FXCODEC_STATUS_ERR_FORMAT;
-        return false;
-      }
+  uint32_t pitch = 0;
+  uint32_t neededData = 0;
+  if (!CFX_DIBitmap::CalculatePitchAndSize(m_SrcWidth, m_SrcHeight, format,
+                                           &pitch, &neededData)) {
+    m_pBmpContext.reset();
+    m_status = FXCODEC_STATUS_ERR_FORMAT;
+    return false;
+  }
 
-      m_SrcBPC = 8;
-      m_clipBox = FX_RECT(0, 0, m_SrcWidth, m_SrcHeight);
-      FX_Free(m_pSrcPalette);
-      if (m_SrcPaletteNumber) {
-        m_pSrcPalette = FX_Alloc(FX_ARGB, m_SrcPaletteNumber);
-        memcpy(m_pSrcPalette, palette.data(),
-               m_SrcPaletteNumber * sizeof(FX_ARGB));
-      } else {
-        m_pSrcPalette = nullptr;
-      }
-      return true;
-    }
-    case FXCODEC_IMAGE_JPG: {
-      CCodec_JpegModule* pJpegModule = m_pCodecMgr->GetJpegModule();
-      m_pJpegContext = pJpegModule->Start();
-      if (!m_pJpegContext) {
-        m_status = FXCODEC_STATUS_ERR_MEMORY;
-        return false;
-      }
-      if (!m_pFile->ReadBlock(m_pSrcBuf, 0, size)) {
-        m_status = FXCODEC_STATUS_ERR_READ;
-        return false;
-      }
-      m_offSet += size;
-      pJpegModule->Input(m_pJpegContext.get(), m_pSrcBuf, size);
-      // Setting jump marker before calling ReadHeader, since a longjmp to
-      // the marker indicates a fatal error.
-      if (setjmp(*m_pJpegContext->GetJumpMark()) == -1) {
-        m_pJpegContext.reset();
-        m_status = FXCODEC_STATUS_ERR_FORMAT;
-        return false;
-      }
+  uint32_t availableData = m_SrcSize > m_offSet ? m_SrcSize - m_offSet : 0;
+  if (neededData > availableData) {
+    m_pBmpContext.reset();
+    m_status = FXCODEC_STATUS_ERR_FORMAT;
+    return false;
+  }
 
-      int32_t readResult =
-          pJpegModule->ReadHeader(m_pJpegContext.get(), &m_SrcWidth,
-                                  &m_SrcHeight, &m_SrcComponents, pAttribute);
-      while (readResult == 2) {
-        FXCODEC_STATUS error_status = FXCODEC_STATUS_ERR_FORMAT;
-        if (!JpegReadMoreData(pJpegModule, error_status)) {
-          m_status = error_status;
-          return false;
-        }
-        readResult =
-            pJpegModule->ReadHeader(m_pJpegContext.get(), &m_SrcWidth,
-                                    &m_SrcHeight, &m_SrcComponents, pAttribute);
-      }
-      if (!readResult) {
-        m_SrcBPC = 8;
-        m_clipBox = FX_RECT(0, 0, m_SrcWidth, m_SrcHeight);
-        return true;
-      }
-      m_pJpegContext.reset();
-      m_status = FXCODEC_STATUS_ERR_FORMAT;
+  m_SrcBPC = 8;
+  m_clipBox = FX_RECT(0, 0, m_SrcWidth, m_SrcHeight);
+  FX_Free(m_pSrcPalette);
+  if (m_SrcPaletteNumber) {
+    m_pSrcPalette = FX_Alloc(FX_ARGB, m_SrcPaletteNumber);
+    memcpy(m_pSrcPalette, palette.data(), m_SrcPaletteNumber * sizeof(FX_ARGB));
+  } else {
+    m_pSrcPalette = nullptr;
+  }
+  return true;
+}
+
+bool CCodec_ProgressiveDecoder::JpegDetectImageType(
+    CFX_DIBAttribute* pAttribute,
+    uint32_t size) {
+  CCodec_JpegModule* pJpegModule = m_pCodecMgr->GetJpegModule();
+  // Setting jump marker before calling Start or ReadHeader, since a longjmp
+  // to the marker indicates a fatal error in these functions.
+  if (setjmp(*m_pJpegContext->GetJumpMark()) == -1) {
+    m_status = FXCODEC_STATUS_ERROR;
+    return false;
+  }
+
+  m_pJpegContext = pJpegModule->Start();
+  if (!m_pJpegContext) {
+    m_status = FXCODEC_STATUS_ERR_MEMORY;
+    return false;
+  }
+  if (!m_pFile->ReadBlock(m_pSrcBuf, 0, size)) {
+    m_status = FXCODEC_STATUS_ERR_READ;
+    return false;
+  }
+  m_offSet += size;
+  pJpegModule->Input(m_pJpegContext.get(), m_pSrcBuf, size);
+  // Setting jump marker before calling ReadHeader, since a longjmp to
+  // the marker indicates a fatal error.
+  if (setjmp(*m_pJpegContext->GetJumpMark()) == -1) {
+    m_pJpegContext.reset();
+    m_status = FXCODEC_STATUS_ERR_FORMAT;
+    return false;
+  }
+
+  int32_t readResult =
+      pJpegModule->ReadHeader(m_pJpegContext.get(), &m_SrcWidth, &m_SrcHeight,
+                              &m_SrcComponents, pAttribute);
+  while (readResult == 2) {
+    FXCODEC_STATUS error_status = FXCODEC_STATUS_ERR_FORMAT;
+    if (!JpegReadMoreData(pJpegModule, error_status)) {
+      m_status = error_status;
       return false;
     }
-    case FXCODEC_IMAGE_PNG: {
-      CCodec_PngModule* pPngModule = m_pCodecMgr->GetPngModule();
-      if (!pPngModule) {
-        m_status = FXCODEC_STATUS_ERR_MEMORY;
-        return false;
-      }
-      m_pPngContext = pPngModule->Start(this);
-      if (!m_pPngContext) {
-        m_status = FXCODEC_STATUS_ERR_MEMORY;
-        return false;
-      }
-      bool bResult = m_pFile->ReadBlock(m_pSrcBuf, 0, size);
-      if (!bResult) {
-        m_status = FXCODEC_STATUS_ERR_READ;
-        return false;
-      }
-      m_offSet += size;
-      bResult =
-          pPngModule->Input(m_pPngContext.get(), m_pSrcBuf, size, pAttribute);
-      while (bResult) {
-        uint32_t remain_size = (uint32_t)m_pFile->GetSize() - m_offSet;
-        uint32_t input_size =
-            remain_size > FXCODEC_BLOCK_SIZE ? FXCODEC_BLOCK_SIZE : remain_size;
-        if (input_size == 0) {
-          m_pPngContext.reset();
-          m_status = FXCODEC_STATUS_ERR_FORMAT;
-          return false;
-        }
-        if (m_pSrcBuf && input_size > m_SrcSize) {
-          FX_Free(m_pSrcBuf);
-          m_pSrcBuf = FX_Alloc(uint8_t, input_size);
-          memset(m_pSrcBuf, 0, input_size);
-          m_SrcSize = input_size;
-        }
-        bResult = m_pFile->ReadBlock(m_pSrcBuf, m_offSet, input_size);
-        if (!bResult) {
-          m_status = FXCODEC_STATUS_ERR_READ;
-          return false;
-        }
-        m_offSet += input_size;
-        bResult = pPngModule->Input(m_pPngContext.get(), m_pSrcBuf, input_size,
-                                    pAttribute);
-      }
-      ASSERT(!bResult);
+    readResult =
+        pJpegModule->ReadHeader(m_pJpegContext.get(), &m_SrcWidth, &m_SrcHeight,
+                                &m_SrcComponents, pAttribute);
+  }
+  if (!readResult) {
+    m_SrcBPC = 8;
+    m_clipBox = FX_RECT(0, 0, m_SrcWidth, m_SrcHeight);
+    return true;
+  }
+  m_pJpegContext.reset();
+  m_status = FXCODEC_STATUS_ERR_FORMAT;
+  return false;
+}
+
+bool CCodec_ProgressiveDecoder::PngDetectImageType(CFX_DIBAttribute* pAttribute,
+                                                   uint32_t size) {
+  CCodec_PngModule* pPngModule = m_pCodecMgr->GetPngModule();
+  if (!pPngModule) {
+    m_status = FXCODEC_STATUS_ERR_MEMORY;
+    return false;
+  }
+  m_pPngContext = pPngModule->Start(this);
+  if (!m_pPngContext) {
+    m_status = FXCODEC_STATUS_ERR_MEMORY;
+    return false;
+  }
+  bool bResult = m_pFile->ReadBlock(m_pSrcBuf, 0, size);
+  if (!bResult) {
+    m_status = FXCODEC_STATUS_ERR_READ;
+    return false;
+  }
+  m_offSet += size;
+  bResult = pPngModule->Input(m_pPngContext.get(), m_pSrcBuf, size, pAttribute);
+  while (bResult) {
+    uint32_t remain_size = static_cast<uint32_t>(m_pFile->GetSize()) - m_offSet;
+    uint32_t input_size =
+        remain_size > FXCODEC_BLOCK_SIZE ? FXCODEC_BLOCK_SIZE : remain_size;
+    if (input_size == 0) {
       m_pPngContext.reset();
-      if (m_SrcPassNumber == 0) {
-        m_status = FXCODEC_STATUS_ERR_FORMAT;
-        return false;
-      }
-      return true;
-    }
-    case FXCODEC_IMAGE_GIF: {
-      CCodec_GifModule* pGifModule = m_pCodecMgr->GetGifModule();
-      if (!pGifModule) {
-        m_status = FXCODEC_STATUS_ERR_MEMORY;
-        return false;
-      }
-      m_pGifContext = pGifModule->Start(this);
-      bool bResult = m_pFile->ReadBlock(m_pSrcBuf, 0, size);
-      if (!bResult) {
-        m_status = FXCODEC_STATUS_ERR_READ;
-        return false;
-      }
-      m_offSet += size;
-      pGifModule->Input(m_pGifContext.get(), m_pSrcBuf, size);
-      m_SrcComponents = 1;
-      CFX_GifDecodeStatus readResult = pGifModule->ReadHeader(
-          m_pGifContext.get(), &m_SrcWidth, &m_SrcHeight, &m_GifPltNumber,
-          (void**)&m_pGifPalette, &m_GifBgIndex, nullptr);
-      while (readResult == CFX_GifDecodeStatus::Unfinished) {
-        FXCODEC_STATUS error_status = FXCODEC_STATUS_ERR_FORMAT;
-        if (!GifReadMoreData(pGifModule, error_status)) {
-          m_pGifContext = nullptr;
-          m_status = error_status;
-          return false;
-        }
-        readResult = pGifModule->ReadHeader(
-            m_pGifContext.get(), &m_SrcWidth, &m_SrcHeight, &m_GifPltNumber,
-            (void**)&m_pGifPalette, &m_GifBgIndex, nullptr);
-      }
-      if (readResult == CFX_GifDecodeStatus::Success) {
-        m_SrcBPC = 8;
-        m_clipBox = FX_RECT(0, 0, m_SrcWidth, m_SrcHeight);
-        return true;
-      }
-      m_pGifContext = nullptr;
       m_status = FXCODEC_STATUS_ERR_FORMAT;
       return false;
     }
-    case FXCODEC_IMAGE_TIF: {
-      CCodec_TiffModule* pTiffModule = m_pCodecMgr->GetTiffModule();
-      if (!pTiffModule) {
-        m_status = FXCODEC_STATUS_ERR_FORMAT;
-        return false;
-      }
-      m_pTiffContext = pTiffModule->CreateDecoder(m_pFile);
-      if (!m_pTiffContext) {
-        m_status = FXCODEC_STATUS_ERR_FORMAT;
-        return false;
-      }
-      int32_t dummy_bpc;
-      bool ret = pTiffModule->LoadFrameInfo(
-          m_pTiffContext.get(), 0, &m_SrcWidth, &m_SrcHeight, &m_SrcComponents,
-          &dummy_bpc, pAttribute);
-      m_SrcComponents = 4;
-      m_clipBox = FX_RECT(0, 0, m_SrcWidth, m_SrcHeight);
-      if (!ret) {
-        m_pTiffContext.reset();
-        m_status = FXCODEC_STATUS_ERR_FORMAT;
-        return false;
-      }
-      return true;
+    if (m_pSrcBuf && input_size > m_SrcSize) {
+      FX_Free(m_pSrcBuf);
+      m_pSrcBuf = FX_Alloc(uint8_t, input_size);
+      memset(m_pSrcBuf, 0, input_size);
+      m_SrcSize = input_size;
     }
-    default:
-      m_status = FXCODEC_STATUS_ERR_FORMAT;
+    bResult = m_pFile->ReadBlock(m_pSrcBuf, m_offSet, input_size);
+    if (!bResult) {
+      m_status = FXCODEC_STATUS_ERR_READ;
+      return false;
+    }
+    m_offSet += input_size;
+    bResult = pPngModule->Input(m_pPngContext.get(), m_pSrcBuf, input_size,
+                                pAttribute);
+  }
+  ASSERT(!bResult);
+  m_pPngContext.reset();
+  if (m_SrcPassNumber == 0) {
+    m_status = FXCODEC_STATUS_ERR_FORMAT;
+    return false;
+  }
+  return true;
+}
+
+bool CCodec_ProgressiveDecoder::GifDetectImageType(CFX_DIBAttribute* pAttribute,
+                                                   uint32_t size) {
+  CCodec_GifModule* pGifModule = m_pCodecMgr->GetGifModule();
+  if (!pGifModule) {
+    m_status = FXCODEC_STATUS_ERR_MEMORY;
+    return false;
+  }
+  m_pGifContext = pGifModule->Start(this);
+  bool bResult = m_pFile->ReadBlock(m_pSrcBuf, 0, size);
+  if (!bResult) {
+    m_status = FXCODEC_STATUS_ERR_READ;
+    return false;
+  }
+  m_offSet += size;
+  pGifModule->Input(m_pGifContext.get(), m_pSrcBuf, size);
+  m_SrcComponents = 1;
+  CFX_GifDecodeStatus readResult = pGifModule->ReadHeader(
+      m_pGifContext.get(), &m_SrcWidth, &m_SrcHeight, &m_GifPltNumber,
+      (void**)&m_pGifPalette, &m_GifBgIndex, nullptr);
+  while (readResult == CFX_GifDecodeStatus::Unfinished) {
+    FXCODEC_STATUS error_status = FXCODEC_STATUS_ERR_FORMAT;
+    if (!GifReadMoreData(pGifModule, error_status)) {
+      m_pGifContext = nullptr;
+      m_status = error_status;
       return false;
+    }
+    readResult = pGifModule->ReadHeader(
+        m_pGifContext.get(), &m_SrcWidth, &m_SrcHeight, &m_GifPltNumber,
+        (void**)&m_pGifPalette, &m_GifBgIndex, nullptr);
   }
+  if (readResult == CFX_GifDecodeStatus::Success) {
+    m_SrcBPC = 8;
+    m_clipBox = FX_RECT(0, 0, m_SrcWidth, m_SrcHeight);
+    return true;
+  }
+  m_pGifContext = nullptr;
+  m_status = FXCODEC_STATUS_ERR_FORMAT;
+  return false;
+}
+
+bool CCodec_ProgressiveDecoder::TifDetectImageType(CFX_DIBAttribute* pAttribute,
+                                                   uint32_t size) {
+  CCodec_TiffModule* pTiffModule = m_pCodecMgr->GetTiffModule();
+  if (!pTiffModule) {
+    m_status = FXCODEC_STATUS_ERR_FORMAT;
+    return false;
+  }
+  m_pTiffContext = pTiffModule->CreateDecoder(m_pFile);
+  if (!m_pTiffContext) {
+    m_status = FXCODEC_STATUS_ERR_FORMAT;
+    return false;
+  }
+  int32_t dummy_bpc;
+  bool ret = pTiffModule->LoadFrameInfo(m_pTiffContext.get(), 0, &m_SrcWidth,
+                                        &m_SrcHeight, &m_SrcComponents,
+                                        &dummy_bpc, pAttribute);
+  m_SrcComponents = 4;
+  m_clipBox = FX_RECT(0, 0, m_SrcWidth, m_SrcHeight);
+  if (!ret) {
+    m_pTiffContext.reset();
+    m_status = FXCODEC_STATUS_ERR_FORMAT;
+    return false;
+  }
+  return true;
 }
 
 FXCODEC_STATUS CCodec_ProgressiveDecoder::LoadImageInfo(