Cleanup parts of fpdf_render_loadimage.cpp.

- Add functions to do pitch calculation.
- Delete dead code.
- Don't bother checking pointers before deleting them.
- Don't bother setting pointers to NULL in dtors.

R=tsepez@chromium.org

Review URL: https://codereview.chromium.org/890883006

2 files changed, 78 insertions, 130 deletions

diff --git a/core/src/fpdfapi/fpdf_render/fpdf_render_loadimage.cpp b/core/src/fpdfapi/fpdf_render/fpdf_render_loadimage.cpp
index f938628f55..45d0078e8a 100644
--- a/core/src/fpdfapi/fpdf_render/fpdf_render_loadimage.cpp
+++ b/core/src/fpdfapi/fpdf_render/fpdf_render_loadimage.cpp
@@ -13,7 +13,9 @@
 #include "../fpdf_page/pageint.h"
 #include "render_int.h"
 
-static unsigned int _GetBits8(FX_LPCBYTE pData, int bitpos, int nbits)
+namespace {
+
+unsigned int _GetBits8(FX_LPCBYTE pData, int bitpos, int nbits)
 {
     unsigned int byte = pData[bitpos / 8];
     if (nbits == 8) {
@@ -29,6 +31,32 @@ static unsigned int _GetBits8(FX_LPCBYTE pData, int bitpos, int nbits)
     }
     return 0;
 }
+
+FX_SAFE_DWORD CalculatePitch8(FX_DWORD bpc,
+                              FX_DWORD components,
+                              int width,
+                              int height)
+{
+    FX_SAFE_DWORD pitch = bpc;
+    pitch *= components;
+    pitch *= width;
+    pitch += 7;
+    pitch /= 8;
+    pitch *= height;
+    return pitch;
+}
+
+FX_SAFE_DWORD CalculatePitch32(int bpp, int width)
+{
+    FX_SAFE_DWORD pitch = bpp;
+    pitch *= width;
+    pitch += 31;
+    pitch /= 8;
+    return pitch;
+}
+
+}  // namespace
+
 CFX_DIBSource* CPDF_Image::LoadDIBSource(CFX_DIBSource** ppMask, FX_DWORD* pMatteColor, FX_BOOL bStdCS, FX_DWORD GroupFamily, FX_BOOL bLoadMask) const
 {
     CPDF_DIBSource* pSource = FX_NEW CPDF_DIBSource;
@@ -112,21 +140,15 @@ CPDF_DIBSource::CPDF_DIBSource()
 }
 CPDF_DIBSource::~CPDF_DIBSource()
 {
-    if (m_pStreamAcc) {
-        delete m_pStreamAcc;
-    }
+    delete m_pStreamAcc;
     if (m_pMaskedLine) {
         FX_Free(m_pMaskedLine);
     }
     if (m_pLineBuf) {
         FX_Free(m_pLineBuf);
     }
-    if (m_pCachedBitmap) {
-        delete m_pCachedBitmap;
-    }
-    if (m_pDecoder) {
-        delete m_pDecoder;
-    }
+    delete m_pCachedBitmap;
+    delete m_pDecoder;
     if (m_pCompData) {
         FX_Free(m_pCompData);
     }
@@ -137,12 +159,8 @@ CPDF_DIBSource::~CPDF_DIBSource()
     if (m_pJbig2Context) {
         ICodec_Jbig2Module* pJbig2Moudle = CPDF_ModuleMgr::Get()->GetJbig2Module();
         pJbig2Moudle->DestroyJbig2Context(m_pJbig2Context);
-        m_pJbig2Context = NULL;
-    }
-    if (m_pGlobalStream) {
-        delete m_pGlobalStream;
     }
-    m_pGlobalStream = NULL;
+    delete m_pGlobalStream;
 }
 CFX_DIBitmap* CPDF_DIBSource::GetBitmap() const
 {
@@ -182,12 +200,8 @@ FX_BOOL CPDF_DIBSource::Load(CPDF_Document* pDoc, const CPDF_Stream* pStream, CP
     if (m_bpc == 0 || m_nComponents == 0) {
         return FALSE;
     }
-    FX_SAFE_DWORD src_pitch = m_bpc;
-    src_pitch *= m_nComponents;
-    src_pitch *= m_Width;
-    src_pitch += 7;
-    src_pitch /= 8;
-    src_pitch *= m_Height;
+    FX_SAFE_DWORD src_pitch =
+        CalculatePitch8(m_bpc, m_nComponents, m_Width, m_Height);
     if (!src_pitch.IsValid()) {
         return FALSE;
     }
@@ -215,10 +229,7 @@ FX_BOOL CPDF_DIBSource::Load(CPDF_Document* pDoc, const CPDF_Stream* pStream, CP
     } else {
         m_bpp = 24;
     }
-    FX_SAFE_DWORD pitch = m_Width;
-    pitch *= m_bpp;
-    pitch += 31;
-    pitch /= 8;
+    FX_SAFE_DWORD pitch = CalculatePitch32(m_bpp, m_Width);
     if (!pitch.IsValid()) {
         return FALSE;
     }
@@ -230,10 +241,7 @@ FX_BOOL CPDF_DIBSource::Load(CPDF_Document* pDoc, const CPDF_Stream* pStream, CP
     if (m_bColorKey) {
         m_bpp = 32;
         m_AlphaFlag = 2;
-        pitch = m_Width;
-        pitch *= m_bpp;
-        pitch += 31;
-        pitch /= 8;
+        FX_SAFE_DWORD pitch = CalculatePitch32(m_bpp, m_Width);
         if (!pitch.IsValid()) {
             return FALSE;
         }
@@ -265,10 +273,7 @@ int	CPDF_DIBSource::ContinueToLoadMask()
     if (!m_bpc || !m_nComponents) {
         return 0;
     }
-    FX_SAFE_DWORD pitch = m_Width;
-    pitch *= m_bpp;
-    pitch += 31;
-    pitch /= 8;
+    FX_SAFE_DWORD pitch = CalculatePitch32(m_bpp, m_Width);
     if (!pitch.IsValid()) {
         return 0;
     }
@@ -280,10 +285,7 @@ int	CPDF_DIBSource::ContinueToLoadMask()
     if (m_bColorKey) {
         m_bpp = 32;
         m_AlphaFlag = 2;
-        pitch = m_Width;
-        pitch *= m_bpp;
-        pitch += 31;
-        pitch /= 8;
+        FX_SAFE_DWORD pitch = CalculatePitch32(m_bpp, m_Width);
         if (!pitch.IsValid()) {
             return 0;
         }
@@ -317,12 +319,8 @@ int	CPDF_DIBSource::StartLoadDIBSource(CPDF_Document* pDoc, const CPDF_Stream* p
     if (m_bpc == 0 || m_nComponents == 0) {
         return 0;
     }
-    FX_SAFE_DWORD src_pitch = m_bpc;
-    src_pitch *= m_nComponents;
-    src_pitch *= m_Width;
-    src_pitch += 7;
-    src_pitch /= 8;
-    src_pitch *= m_Height;
+    FX_SAFE_DWORD src_pitch =
+        CalculatePitch8(m_bpc, m_nComponents, m_Width, m_Height);
     if (!src_pitch.IsValid()) {
         return 0;
     }
@@ -383,9 +381,7 @@ int	CPDF_DIBSource::ContinueLoadDIBSource(IFX_Pause* pPause)
             if (ret < 0) {
                 delete m_pCachedBitmap;
                 m_pCachedBitmap = NULL;
-                if (m_pGlobalStream) {
-                    delete m_pGlobalStream;
-                }
+                delete m_pGlobalStream;
                 m_pGlobalStream = NULL;
                 pJbig2Moudle->DestroyJbig2Context(m_pJbig2Context);
                 m_pJbig2Context = NULL;
@@ -411,9 +407,7 @@ int	CPDF_DIBSource::ContinueLoadDIBSource(IFX_Pause* pPause)
         if (ret < 0) {
             delete m_pCachedBitmap;
             m_pCachedBitmap = NULL;
-            if (m_pGlobalStream) {
-                delete m_pGlobalStream;
-            }
+            delete m_pGlobalStream;
             m_pGlobalStream = NULL;
             pJbig2Moudle->DestroyJbig2Context(m_pJbig2Context);
             m_pJbig2Context = NULL;
@@ -578,7 +572,7 @@ int CPDF_DIBSource::CreateDecoder()
     } else if (decoder == FX_BSTRC("DCTDecode")) {
         m_pDecoder = CPDF_ModuleMgr::Get()->GetJpegModule()->CreateDecoder(src_data, src_size, m_Width, m_Height,
                      m_nComponents, pParams ? pParams->GetInteger(FX_BSTR("ColorTransform"), 1) : 1);
-        if (NULL == m_pDecoder) {
+        if (!m_pDecoder) {
             FX_BOOL bTransform = FALSE;
             int comps, bpc;
             ICodec_JpegModule* pJpegModule = CPDF_ModuleMgr::Get()->GetJpegModule();
@@ -617,29 +611,25 @@ int CPDF_DIBSource::CreateDecoder()
     } else if (decoder == FX_BSTRC("RunLengthDecode")) {
         m_pDecoder = CPDF_ModuleMgr::Get()->GetCodecModule()->GetBasicModule()->CreateRunLengthDecoder(src_data, src_size, m_Width, m_Height, m_nComponents, m_bpc);
     }
-    if (m_pDecoder) {
-        FX_SAFE_DWORD requested_pitch = m_bpc;
-        requested_pitch *= m_nComponents;
-        requested_pitch *= m_Width;
-        requested_pitch += 7;
-        requested_pitch /= 8;
-        if (!requested_pitch.IsValid()) {
-            return 0;
-        }
-        FX_SAFE_DWORD provided_pitch = m_pDecoder->GetBPC();
-        provided_pitch *= m_pDecoder->CountComps();
-        provided_pitch *= m_pDecoder->GetWidth();
-        provided_pitch += 7;
-        provided_pitch /= 8;
-        if (!provided_pitch.IsValid()) {
-            return 0;
-        }
-        if (provided_pitch.ValueOrDie() < requested_pitch.ValueOrDie()) {
-            return 0;
-        }
-        return 1;
+    if (!m_pDecoder)
+        return 0;
+
+    FX_SAFE_DWORD requested_pitch =
+        CalculatePitch8(m_bpc, m_nComponents, m_Width, 1);
+    if (!requested_pitch.IsValid()) {
+        return 0;
     }
-    return 0;
+    FX_SAFE_DWORD provided_pitch = CalculatePitch8(m_pDecoder->GetBPC(),
+                                                   m_pDecoder->CountComps(),
+                                                   m_pDecoder->GetWidth(),
+                                                   1);
+    if (!provided_pitch.IsValid()) {
+        return 0;
+    }
+    if (provided_pitch.ValueOrDie() < requested_pitch.ValueOrDie()) {
+        return 0;
+    }
+    return 1;
 }
 void CPDF_DIBSource::LoadJpxBitmap()
 {
@@ -729,37 +719,6 @@ void CPDF_DIBSource::LoadJpxBitmap()
     }
     m_bpc = 8;
 }
-void CPDF_DIBSource::LoadJbig2Bitmap()
-{
-    ICodec_Jbig2Module* pJbig2Module = CPDF_ModuleMgr::Get()->GetJbig2Module();
-    if (pJbig2Module == NULL) {
-        return;
-    }
-    CPDF_StreamAcc* pGlobalStream = NULL;
-    if (m_pStreamAcc->GetImageParam()) {
-        CPDF_Stream* pGlobals = m_pStreamAcc->GetImageParam()->GetStream(FX_BSTRC("JBIG2Globals"));
-        if (pGlobals) {
-            pGlobalStream = FX_NEW CPDF_StreamAcc;
-            pGlobalStream->LoadAllData(pGlobals, FALSE);
-        }
-    }
-    m_pCachedBitmap = FX_NEW CFX_DIBitmap;
-    if (!m_pCachedBitmap->Create(m_Width, m_Height, m_bImageMask ? FXDIB_1bppMask : FXDIB_1bppRgb)) {
-        return;
-    }
-    int ret = pJbig2Module->Decode(m_Width, m_Height, m_pStreamAcc->GetData(), m_pStreamAcc->GetSize(),
-                                   pGlobalStream ? pGlobalStream->GetData() : NULL, pGlobalStream ? pGlobalStream->GetSize() : 0,
-                                   m_pCachedBitmap->GetBuffer(), m_pCachedBitmap->GetPitch());
-    if (ret < 0) {
-        delete m_pCachedBitmap;
-        m_pCachedBitmap = NULL;
-    }
-    if (pGlobalStream) {
-        delete pGlobalStream;
-    }
-    m_bpc = 1;
-    m_nComponents = 1;
-}
 CPDF_DIBSource* CPDF_DIBSource::LoadMask(FX_DWORD& MatteColor)
 {
     MatteColor = 0xffffffff;
@@ -1083,11 +1042,7 @@ FX_LPCBYTE CPDF_DIBSource::GetScanline(int line) const
     if (m_bpc == 0) {
         return NULL;
     }
-    FX_SAFE_DWORD src_pitch = m_Width;
-    src_pitch *= m_bpc;
-    src_pitch *= m_nComponents;
-    src_pitch += 7;
-    src_pitch /= 8;
+    FX_SAFE_DWORD src_pitch = CalculatePitch8(m_bpc, m_nComponents, m_Width, 1);
     if (!src_pitch.IsValid())
         return NULL;
     FX_DWORD src_pitch_value = src_pitch.ValueOrDie();
@@ -1223,12 +1178,8 @@ void CPDF_DIBSource::DownSampleScanline(int line, FX_LPBYTE dest_scan, int dest_
     }
 
     FX_DWORD src_width = m_Width;
-    FX_SAFE_DWORD pitch = src_width;
-    pitch *= m_bpc;
-    pitch *= m_nComponents;
-    pitch += 7;
-    pitch /= 8;
-    if (!pitch.IsValid()) { 
+    FX_SAFE_DWORD pitch = CalculatePitch8(m_bpc, m_nComponents, m_Width, 1);
+    if (!pitch.IsValid()) {
         return;
     }
 
@@ -1240,10 +1191,10 @@ void CPDF_DIBSource::DownSampleScanline(int line, FX_LPBYTE dest_scan, int dest_
     } else {
         FX_DWORD src_pitch = pitch.ValueOrDie();
         pitch *= (line+1);
-        if (!pitch.IsValid()) { 
+        if (!pitch.IsValid()) {
             return;
         }
- 
+
         if (m_pStreamAcc->GetSize() >= pitch.ValueOrDie()) {
             pSrcLine = m_pStreamAcc->GetData() + line * src_pitch;
         }
@@ -1481,9 +1432,6 @@ CPDF_ProgressiveImageLoaderHandle::CPDF_ProgressiveImageLoaderHandle()
 }
 CPDF_ProgressiveImageLoaderHandle::~CPDF_ProgressiveImageLoaderHandle()
 {
-    m_pImageLoader = NULL;
-    m_pCache = NULL;
-    m_pImage = NULL;
 }
 FX_BOOL CPDF_ProgressiveImageLoaderHandle::Start(CPDF_ImageLoader* pImageLoader, const CPDF_ImageObject* pImage, CPDF_PageRenderCache* pCache, FX_BOOL bStdCS, FX_DWORD GroupFamily, FX_BOOL bLoadMask, CPDF_RenderStatus* pRenderStatus, FX_INT32 nDownsampleWidth, FX_INT32 nDownsampleHeight)
 {
@@ -1565,12 +1513,7 @@ FX_BOOL	CPDF_ImageLoader::Continue(FX_LPVOID LoadHandle, IFX_Pause* pPause)
 CPDF_ImageLoader::~CPDF_ImageLoader()
 {
     if (!m_bCached) {
-        if (m_pBitmap) {
-            delete m_pBitmap;
-            m_pBitmap = NULL;
-        }
-        if (m_pMask) {
-            delete m_pMask;
-        }
+        delete m_pBitmap;
+        delete m_pMask;
     }
 }
diff --git a/core/src/fpdfapi/fpdf_render/render_int.h b/core/src/fpdfapi/fpdf_render/render_int.h
index bd7d375837..70c41ca93c 100644
--- a/core/src/fpdfapi/fpdf_render/render_int.h
+++ b/core/src/fpdfapi/fpdf_render/render_int.h
@@ -419,9 +419,8 @@ protected:
     CPDF_DIBSource*		LoadMask(FX_DWORD& MatteColor);
     CPDF_DIBSource*		LoadMaskDIB(CPDF_Stream* pMask);
     void				LoadJpxBitmap();
-    void				LoadJbig2Bitmap();
     void				LoadPalette();
-    FX_BOOL				CreateDecoder();
+    int					CreateDecoder();
     void				TranslateScanline24bpp(FX_LPBYTE dest_scan, FX_LPCBYTE src_scan) const;
     void                ValidateDictParam();
     CPDF_Document*		m_pDocument;
@@ -429,9 +428,15 @@ protected:
     CPDF_StreamAcc*		m_pStreamAcc;
     const CPDF_Dictionary*	m_pDict;
     CPDF_ColorSpace*	m_pColorSpace;
-    FX_DWORD			m_Family, m_bpc, m_bpc_orig, m_nComponents, m_GroupFamily;
+    FX_DWORD			m_Family;
+    FX_DWORD			m_bpc;
+    FX_DWORD			m_bpc_orig;
+    FX_DWORD			m_nComponents;
+    FX_DWORD			m_GroupFamily;
     FX_BOOL				m_bLoadMask;
-    FX_BOOL				m_bDefaultDecode, m_bImageMask, m_bColorKey;
+    FX_BOOL				m_bDefaultDecode;
+    FX_BOOL				m_bImageMask;
+    FX_BOOL				m_bColorKey;
     DIB_COMP_DATA*		m_pCompData;
     FX_LPBYTE			m_pLineBuf;
     FX_LPBYTE			m_pMaskedLine;