Introduce CPDFPageFromFPDFPage()

fpdfsdk/src/fpdfeditpage.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 "../../public/fpdf_edit.h"
 #include "../../public/fpdf_formfill.h"
 #include "../include/fsdk_define.h"
 
@@ skipping 67 matching lines @@
   pPageDict->SetAt("Resources", new CPDF_Dictionary);
 
   CPDF_Page* pPage = new CPDF_Page;
   pPage->Load(pDoc, pPageDict);
   pPage->ParseContent();
 
   return pPage;
 }
 
 DLLEXPORT int STDCALL FPDFPage_GetRotation(FPDF_PAGE page) {
-  CPDF_Page* pPage = (CPDF_Page*)page;
+  CPDF_Page* pPage = CPDFPageFromFPDFPage(page);
   if (!pPage || !pPage->m_pFormDict || !pPage->m_pFormDict->KeyExist("Type") ||
       !pPage->m_pFormDict->GetElement("Type")->GetDirect() ||
       pPage->m_pFormDict->GetElement("Type")->GetDirect()->GetString().Compare(
           "Page")) {
     return -1;
   }
   CPDF_Dictionary* pDict = pPage->m_pFormDict;
 
   int rotate = 0;
   if (pDict != NULL) {
@@ skipping 23 matching lines @@
     }
   } else {
     return -1;
   }
 
   return rotate;
 }
 
 DLLEXPORT void STDCALL FPDFPage_InsertObject(FPDF_PAGE page,
                                              FPDF_PAGEOBJECT page_obj) {
-  CPDF_Page* pPage = (CPDF_Page*)page;
+  CPDF_Page* pPage = CPDFPageFromFPDFPage(page);
   if (!pPage || !pPage->m_pFormDict || !pPage->m_pFormDict->KeyExist("Type") ||
       !pPage->m_pFormDict->GetElement("Type")->GetDirect() ||
       pPage->m_pFormDict->GetElement("Type")->GetDirect()->GetString().Compare(
           "Page")) {
     return;
   }
   CPDF_PageObject* pPageObj = (CPDF_PageObject*)page_obj;
   if (pPageObj == NULL)
     return;
   FX_POSITION LastPersition = pPage->GetLastObjectPosition();
@@ skipping 21 matching lines @@
       break;
     }
     case FPDF_PAGEOBJ_FORM: {
       CPDF_FormObject* pFormObj = (CPDF_FormObject*)pPageObj;
       pFormObj->CalcBoundingBox();
       break;
     }
     default:
       break;
   }
-
-  //    pPage->ParseContent();
-  // pPage->GenerateContent();
 }
 
 DLLEXPORT int STDCALL FPDFPage_CountObject(FPDF_PAGE page) {
-  CPDF_Page* pPage = (CPDF_Page*)page;
+  CPDF_Page* pPage = CPDFPageFromFPDFPage(page);
   if (!pPage || !pPage->m_pFormDict || !pPage->m_pFormDict->KeyExist("Type") ||
       !pPage->m_pFormDict->GetElement("Type")->GetDirect() ||
       pPage->m_pFormDict->GetElement("Type")->GetDirect()->GetString().Compare(
           "Page")) {
     return -1;
   }
   return pPage->CountObjects();
-  //    return 0;
 }
 
 DLLEXPORT FPDF_PAGEOBJECT STDCALL FPDFPage_GetObject(FPDF_PAGE page,
                                                      int index) {
-  CPDF_Page* pPage = (CPDF_Page*)page;
+  CPDF_Page* pPage = CPDFPageFromFPDFPage(page);
   if (!pPage || !pPage->m_pFormDict || !pPage->m_pFormDict->KeyExist("Type") ||
       pPage->m_pFormDict->GetElement("Type")->GetDirect()->GetString().Compare(
           "Page")) {
     return NULL;
   }
   return pPage->GetObjectByIndex(index);
-  //    return NULL;
 }
 
 DLLEXPORT FPDF_BOOL STDCALL FPDFPage_HasTransparency(FPDF_PAGE page) {
-  if (!page)
-    return FALSE;
-  CPDF_Page* pPage = (CPDF_Page*)page;
-
-  return pPage->BackgroundAlphaNeeded();
+  CPDF_Page* pPage = CPDFPageFromFPDFPage(page);
+  return pPage && pPage->BackgroundAlphaNeeded();
 }
 
 DLLEXPORT FPDF_BOOL STDCALL
 FPDFPageObj_HasTransparency(FPDF_PAGEOBJECT pageObject) {
   if (!pageObject)
     return FALSE;
   CPDF_PageObject* pPageObj = (CPDF_PageObject*)pageObject;
 
   const CPDF_GeneralStateData* pGeneralState = pPageObj->m_GeneralState;
   int blend_type =
@@ skipping 21 matching lines @@
       return TRUE;
     if (pFormObj->m_pForm &&
         (!(pFormObj->m_pForm->m_Transparency & PDFTRANS_ISOLATED) &&
          (pFormObj->m_pForm->m_Transparency & PDFTRANS_GROUP)))
       return TRUE;
   }
   return FALSE;
 }
 
 DLLEXPORT FPDF_BOOL STDCALL FPDFPage_GenerateContent(FPDF_PAGE page) {
-  CPDF_Page* pPage = (CPDF_Page*)page;
+  CPDF_Page* pPage = CPDFPageFromFPDFPage(page);
   if (!pPage || !pPage->m_pFormDict || !pPage->m_pFormDict->KeyExist("Type") ||
       !pPage->m_pFormDict->GetElement("Type")->GetDirect() ||
       pPage->m_pFormDict->GetElement("Type")->GetDirect()->GetString().Compare(
           "Page")) {
     return FALSE;
   }
   CPDF_PageContentGenerate CG(pPage);
   CG.GenerateContent();
 
   return TRUE;
@@ skipping 14 matching lines @@
                           (FX_FLOAT)e, (FX_FLOAT)f);
   pPageObj->Transform(matrix);
 }
 DLLEXPORT void STDCALL FPDFPage_TransformAnnots(FPDF_PAGE page,
                                                 double a,
                                                 double b,
                                                 double c,
                                                 double d,
                                                 double e,
                                                 double f) {
-  if (page == NULL)
+  CPDF_Page* pPage = CPDFPageFromFPDFPage(page);
+  if (!pPage)
     return;
-  CPDF_Page* pPage = (CPDF_Page*)page;
   CPDF_AnnotList AnnotList(pPage);
   for (int i = 0; i < AnnotList.Count(); i++) {
     CPDF_Annot* pAnnot = AnnotList.GetAt(i);
     // transformAnnots Rectangle
     CPDF_Rect rect;
     pAnnot->GetRect(rect);
     CFX_AffineMatrix matrix((FX_FLOAT)a, (FX_FLOAT)b, (FX_FLOAT)c, (FX_FLOAT)d,
                             (FX_FLOAT)e, (FX_FLOAT)f);
     rect.Transform(&matrix);
     CPDF_Array* pRectArray = NULL;
     pRectArray = pAnnot->GetAnnotDict()->GetArray("Rect");
     if (!pRectArray)
       pRectArray = CPDF_Array::Create();
     pRectArray->SetAt(0, new CPDF_Number(rect.left));
     pRectArray->SetAt(1, new CPDF_Number(rect.bottom));
     pRectArray->SetAt(2, new CPDF_Number(rect.right));
     pRectArray->SetAt(3, new CPDF_Number(rect.top));
     pAnnot->GetAnnotDict()->SetAt("Rect", pRectArray);
 
     // Transform AP's rectangle
     // To Do
   }
 }
 
 DLLEXPORT void STDCALL FPDFPage_SetRotation(FPDF_PAGE page, int rotate) {
-  CPDF_Page* pPage = (CPDF_Page*)page;
+  CPDF_Page* pPage = CPDFPageFromFPDFPage(page);
   if (!pPage || !pPage->m_pFormDict || !pPage->m_pFormDict->KeyExist("Type") ||
       !pPage->m_pFormDict->GetElement("Type")->GetDirect() ||
       pPage->m_pFormDict->GetElement("Type")->GetDirect()->GetString().Compare(
           "Page")) {
     return;
   }
   CPDF_Dictionary* pDict = pPage->m_pFormDict;
   rotate %= 4;
 
   pDict->SetAt("Rotate", new CPDF_Number(rotate * 90));
 }