Add type cast definitions for CPDF_Stream.

core/src/fpdfapi/fpdf_render/fpdf_render_pattern.cpp

 // Copyright 2014 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 "../../../include/fpdfapi/fpdf_render.h"
 #include "../../../include/fpdfapi/fpdf_pageobj.h"
 #include "../../../include/fxge/fx_ge.h"
 #include "../fpdf_page/pageint.h"
@@ skipping 390 matching lines @@
       R += r_unit;
       G += g_unit;
       B += b_unit;
       FXARGB_SETDIB(dib_buf,
                     FXARGB_MAKE(alpha, (int32_t)(R * 255), (int32_t)(G * 255),
                                 (int32_t)(B * 255)));
       dib_buf += 4;
     }
   }
 }
 static void _DrawFreeGouraudShading(CFX_DIBitmap* pBitmap,

[Tom Sepez, 2015/10/22 17:16:45]

nit: as long as you're mucking with this, can we lose the leading _ ? _CAPITAL
is reserved for the implementation and should not be used. 

[dsinclair, 2015/10/22 17:42:56]

Done.

                                     CFX_AffineMatrix* pObject2Bitmap,
                                     CPDF_Stream* pShadingStream,
                                     CPDF_Function** pFuncs,
                                     int nFuncs,
                                     CPDF_ColorSpace* pCS,
                                     int alpha) {
   ASSERT(pBitmap->GetFormat() == FXDIB_Argb);
-  if (pShadingStream->GetType() != PDFOBJ_STREAM) {
+  if (!pShadingStream->IsStream())

[Tom Sepez, 2015/10/22 17:16:45]

Can a stream be not IsStream() ?  Either this should take an object argument and
we call ToStream here, or the callers should call ToStream() and we do a null
check here.

[dsinclair, 2015/10/22 17:42:56]

Done. Probably bad casts in the past.

     return;
-  }
+
   CPDF_MeshStream stream;
-  if (!stream.Load(pShadingStream, pFuncs, nFuncs, pCS)) {
+  if (!stream.Load(pShadingStream, pFuncs, nFuncs, pCS))
     return;
-  }
+
   CPDF_MeshVertex triangle[3];
   FXSYS_memset(triangle, 0, sizeof(triangle));
 
   while (!stream.m_BitStream.IsEOF()) {
     CPDF_MeshVertex vertex;
     FX_DWORD flag = stream.GetVertex(vertex, pObject2Bitmap);
     if (flag == 0) {
       triangle[0] = vertex;
       for (int j = 1; j < 3; j++) {
         stream.GetVertex(triangle[j], pObject2Bitmap);
       }
     } else {
       if (flag == 1) {
         triangle[0] = triangle[1];
       }
       triangle[1] = triangle[2];
       triangle[2] = vertex;
     }
     _DrawGouraud(pBitmap, alpha, triangle);
   }
 }
 static void _DrawLatticeGouraudShading(CFX_DIBitmap* pBitmap,
                                        CFX_AffineMatrix* pObject2Bitmap,
                                        CPDF_Stream* pShadingStream,
                                        CPDF_Function** pFuncs,
                                        int nFuncs,
                                        CPDF_ColorSpace* pCS,
                                        int alpha) {
   ASSERT(pBitmap->GetFormat() == FXDIB_Argb);
-  if (pShadingStream->GetType() != PDFOBJ_STREAM) {
+  if (!pShadingStream->IsStream())

[Tom Sepez, 2015/10/22 17:16:45]

ditto

[dsinclair, 2015/10/22 17:42:56]

Done.

     return;
-  }
+
   int row_verts = pShadingStream->GetDict()->GetInteger("VerticesPerRow");
-  if (row_verts < 2) {
+  if (row_verts < 2)
     return;
-  }
+
   CPDF_MeshStream stream;
-  if (!stream.Load(pShadingStream, pFuncs, nFuncs, pCS)) {
+  if (!stream.Load(pShadingStream, pFuncs, nFuncs, pCS))
     return;
-  }
+
   CPDF_MeshVertex* vertex = FX_Alloc2D(CPDF_MeshVertex, row_verts, 2);
   if (!stream.GetVertexRow(vertex, row_verts, pObject2Bitmap)) {
     FX_Free(vertex);
     return;
   }
   int last_index = 0;
   while (1) {
     CPDF_MeshVertex* last_row = vertex + last_index * row_verts;
     CPDF_MeshVertex* this_row = vertex + (1 - last_index) * row_verts;
     if (!stream.GetVertexRow(this_row, row_verts, pObject2Bitmap)) {
@@ skipping 275 matching lines @@
 static void _DrawCoonPatchMeshes(FX_BOOL bTensor,
                                  CFX_DIBitmap* pBitmap,
                                  CFX_AffineMatrix* pObject2Bitmap,
                                  CPDF_Stream* pShadingStream,
                                  CPDF_Function** pFuncs,
                                  int nFuncs,
                                  CPDF_ColorSpace* pCS,
                                  int fill_mode,
                                  int alpha) {
   ASSERT(pBitmap->GetFormat() == FXDIB_Argb);
-  if (pShadingStream->GetType() != PDFOBJ_STREAM) {
+  if (!pShadingStream->IsStream())

[Tom Sepez, 2015/10/22 17:16:45]

ditto ditto

[dsinclair, 2015/10/22 17:42:56]

Done.

     return;
-  }
+
   CFX_FxgeDevice device;
   device.Attach(pBitmap);
   CPDF_MeshStream stream;
-  if (!stream.Load(pShadingStream, pFuncs, nFuncs, pCS)) {
+  if (!stream.Load(pShadingStream, pFuncs, nFuncs, pCS))
     return;
-  }
-
-  if (!_CheckCoonTensorPara(stream)) {
+  if (!_CheckCoonTensorPara(stream))
     return;
-  }
 
   CPDF_PatchDrawer patch;
   patch.alpha = alpha;
   patch.pDevice = &device;
   patch.fill_mode = fill_mode;
   patch.path.SetPointCount(13);
   FX_PATHPOINT* pPoints = patch.path.GetPoints();
   pPoints[0].m_Flag = FXPT_MOVETO;
   for (int i = 1; i < 13; i++) {
     pPoints[i].m_Flag = FXPT_BEZIERTO;
@@ skipping 100 matching lines @@
     case 2:
       _DrawAxialShading(pBitmap, &FinalMatrix, pDict, pFuncs, nFuncs,
                         pColorSpace, alpha);
       break;
     case 3:
       _DrawRadialShading(pBitmap, &FinalMatrix, pDict, pFuncs, nFuncs,
                          pColorSpace, alpha);
       break;
     case 4: {
       _DrawFreeGouraudShading(pBitmap, &FinalMatrix,
-                              (CPDF_Stream*)pPattern->m_pShadingObj, pFuncs,
-                              nFuncs, pColorSpace, alpha);
+                              ToStream(pPattern->m_pShadingObj), pFuncs, nFuncs,
+                              pColorSpace, alpha);
     } break;
     case 5: {
       _DrawLatticeGouraudShading(pBitmap, &FinalMatrix,
-                                 (CPDF_Stream*)pPattern->m_pShadingObj, pFuncs,
+                                 ToStream(pPattern->m_pShadingObj), pFuncs,
                                  nFuncs, pColorSpace, alpha);
     } break;
     case 6:
     case 7: {
       _DrawCoonPatchMeshes(pPattern->m_ShadingType - 6, pBitmap, &FinalMatrix,
-                           (CPDF_Stream*)pPattern->m_pShadingObj, pFuncs,
-                           nFuncs, pColorSpace, fill_mode, alpha);
+                           ToStream(pPattern->m_pShadingObj), pFuncs, nFuncs,
+                           pColorSpace, fill_mode, alpha);
     } break;
   }
   if (bAlphaMode) {
     pBitmap->LoadChannel(FXDIB_Red, pBitmap, FXDIB_Alpha);
   }
   if (m_Options.m_ColorMode == RENDER_COLOR_GRAY) {
     pBitmap->ConvertColorScale(m_Options.m_ForeColor, m_Options.m_BackColor);
   }
   buffer.OutputToDevice();
 }
@@ skipping 295 matching lines @@
     }
   }
   if (bStroke) {
     CPDF_Color& StrokeColor = *pPathObj->m_ColorState.GetStrokeColor();
     if (StrokeColor.m_pCS && StrokeColor.m_pCS->GetFamily() == PDFCS_PATTERN) {
       DrawPathWithPattern(pPathObj, pObj2Device, &StrokeColor, TRUE);
       bStroke = FALSE;
     }
   }
 }