Cleanup CPDFXFA_Page.

- Use std::unique_ptr.
- Make dtor protected.
- Simplify logic.
- Remove unused bits from CXFA_FFPageView as well.

Review URL: https://codereview.chromium.org/1878963004

3 files changed, 37 insertions, 51 deletions

diff --git a/fpdfsdk/fpdfxfa/fpdfxfa_doc.cpp b/fpdfsdk/fpdfxfa/fpdfxfa_doc.cpp
index aa1a1a82c7..7fa258c506 100644
--- a/fpdfsdk/fpdfxfa/fpdfxfa_doc.cpp
+++ b/fpdfsdk/fpdfxfa/fpdfxfa_doc.cpp
@@ -4,12 +4,13 @@
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
+#include "fpdfsdk/fpdfxfa/include/fpdfxfa_doc.h"
+
 #include "core/fpdfapi/fpdf_parser/include/cpdf_array.h"
 #include "core/fpdfapi/fpdf_parser/include/cpdf_document.h"
 #include "core/fpdfapi/fpdf_parser/include/cpdf_stream_acc.h"
 #include "core/fpdfapi/fpdf_parser/include/cpdf_string.h"
 #include "fpdfsdk/fpdfxfa/include/fpdfxfa_app.h"
-#include "fpdfsdk/fpdfxfa/include/fpdfxfa_doc.h"
 #include "fpdfsdk/fpdfxfa/include/fpdfxfa_page.h"
 #include "fpdfsdk/fpdfxfa/include/fpdfxfa_util.h"
 #include "fpdfsdk/include/fsdk_define.h"
@@ -168,7 +169,7 @@ CPDFXFA_Page* CPDFXFA_Document::GetPage(int page_index) {
     return pPage;
   pPage = new CPDFXFA_Page(this, page_index);
   if (!pPage->LoadPage()) {
-    delete pPage;
+    pPage->Release();
     return nullptr;
   }
   m_XFAPageList.SetAt(page_index, pPage);
@@ -508,8 +509,6 @@ void CPDFXFA_Document::PageViewEvent(CXFA_FFPageView* pPageView,
       m_pSDKDoc->RemovePageView(pPage);
       CXFA_FFPageView* pXFAPageView = pXFADocView->GetPageView(iPageIter);
       pPage->SetXFAPageView(pXFAPageView);
-      if (pXFAPageView)
-        pXFAPageView->LoadPageView(nullptr);
     }
 
     int flag = (nNewCount < m_nPageCount) ? FXFA_PAGEVIEWEVENT_POSTREMOVED
diff --git a/fpdfsdk/fpdfxfa/fpdfxfa_page.cpp b/fpdfsdk/fpdfxfa/fpdfxfa_page.cpp
index 8179db5c11..8c0d6bbf98 100644
--- a/fpdfsdk/fpdfxfa/fpdfxfa_page.cpp
+++ b/fpdfsdk/fpdfxfa/fpdfxfa_page.cpp
@@ -16,22 +16,15 @@
 #include "xfa/fxfa/include/xfa_ffpageview.h"
 
 CPDFXFA_Page::CPDFXFA_Page(CPDFXFA_Document* pDoc, int page_index)
-    : m_pPDFPage(NULL),
-      m_pXFAPageView(NULL),
-      m_iPageIndex(page_index),
+    : m_pXFAPageView(nullptr),
       m_pDocument(pDoc),
+      m_iPageIndex(page_index),
       m_iRef(1) {}
 
-CPDFXFA_Page::~CPDFXFA_Page() {
-  if (m_pPDFPage)
-    delete m_pPDFPage;
-  m_pPDFPage = NULL;
-  m_pXFAPageView = NULL;
-}
+CPDFXFA_Page::~CPDFXFA_Page() {}
 
 void CPDFXFA_Page::Release() {
-  m_iRef--;
-  if (m_iRef > 0)
+  if (--m_iRef > 0)
     return;
 
   if (m_pDocument)
@@ -43,31 +36,27 @@ void CPDFXFA_Page::Release() {
 FX_BOOL CPDFXFA_Page::LoadPDFPage() {
   if (!m_pDocument)
     return FALSE;
+
   CPDF_Document* pPDFDoc = m_pDocument->GetPDFDoc();
-  if (pPDFDoc) {
-    CPDF_Dictionary* pDict = pPDFDoc->GetPage(m_iPageIndex);
-    if (pDict == NULL)
-      return FALSE;
-    if (m_pPDFPage) {
-      if (m_pPDFPage->m_pFormDict == pDict)
-        return TRUE;
+  if (!pPDFDoc)
+    return FALSE;
 
-      delete m_pPDFPage;
-      m_pPDFPage = NULL;
-    }
+  CPDF_Dictionary* pDict = pPDFDoc->GetPage(m_iPageIndex);
+  if (!pDict)
+    return FALSE;
 
-    m_pPDFPage = new CPDF_Page;
+  if (!m_pPDFPage || m_pPDFPage->m_pFormDict != pDict) {
+    m_pPDFPage.reset(new CPDF_Page);
     m_pPDFPage->Load(pPDFDoc, pDict);
     m_pPDFPage->ParseContent(nullptr);
-    return TRUE;
   }
-
-  return FALSE;
+  return TRUE;
 }
 
 FX_BOOL CPDFXFA_Page::LoadXFAPageView() {
   if (!m_pDocument)
     return FALSE;
+
   CXFA_FFDoc* pXFADoc = m_pDocument->GetXFADoc();
   if (!pXFADoc)
     return FALSE;
@@ -80,11 +69,7 @@ FX_BOOL CPDFXFA_Page::LoadXFAPageView() {
   if (!pPageView)
     return FALSE;
 
-  if (m_pXFAPageView == pPageView)
-    return TRUE;
-
   m_pXFAPageView = pPageView;
-  (void)m_pXFAPageView->LoadPageView(nullptr);
   return TRUE;
 }
 
@@ -110,17 +95,13 @@ FX_BOOL CPDFXFA_Page::LoadPDFPage(CPDF_Dictionary* pageDict) {
   if (!m_pDocument || m_iPageIndex < 0 || !pageDict)
     return FALSE;
 
-  if (m_pPDFPage)
-    delete m_pPDFPage;
-
-  m_pPDFPage = new CPDF_Page();
+  m_pPDFPage.reset(new CPDF_Page());
   m_pPDFPage->Load(m_pDocument->GetPDFDoc(), pageDict);
   m_pPDFPage->ParseContent(nullptr);
-
   return TRUE;
 }
 
-FX_FLOAT CPDFXFA_Page::GetPageWidth() {
+FX_FLOAT CPDFXFA_Page::GetPageWidth() const {
   if (!m_pPDFPage && !m_pXFAPageView)
     return 0.0f;
 
@@ -145,7 +126,7 @@ FX_FLOAT CPDFXFA_Page::GetPageWidth() {
   return 0.0f;
 }
 
-FX_FLOAT CPDFXFA_Page::GetPageHeight() {
+FX_FLOAT CPDFXFA_Page::GetPageHeight() const {
   if (!m_pPDFPage && !m_pXFAPageView)
     return 0.0f;
 
diff --git a/fpdfsdk/fpdfxfa/include/fpdfxfa_page.h b/fpdfsdk/fpdfxfa/include/fpdfxfa_page.h
index 2c860ffbdc..0f278912d6 100644
--- a/fpdfsdk/fpdfxfa/include/fpdfxfa_page.h
+++ b/fpdfsdk/fpdfxfa/include/fpdfxfa_page.h
@@ -7,6 +7,8 @@
 #ifndef FPDFSDK_FPDFXFA_INCLUDE_FPDFXFA_PAGE_H_
 #define FPDFSDK_FPDFXFA_INCLUDE_FPDFXFA_PAGE_H_
 
+#include <memory>
+
 #include "core/fpdfapi/fpdf_parser/include/cpdf_dictionary.h"
 #include "core/fpdfapi/include/cpdf_modulemgr.h"
 #include "core/fxcrt/include/fx_coordinates.h"
@@ -19,22 +21,23 @@ class CXFA_FFPageView;
 class CPDFXFA_Page {
  public:
   CPDFXFA_Page(CPDFXFA_Document* pDoc, int page_index);
-  ~CPDFXFA_Page();
 
-  void Release();
   void AddRef() { m_iRef++; }
+  void Release();
+
   FX_BOOL LoadPage();
   FX_BOOL LoadPDFPage(CPDF_Dictionary* pageDict);
-  CPDFXFA_Document* GetDocument() { return m_pDocument; }
-  int GetPageIndex() { return m_iPageIndex; }
-  CPDF_Page* GetPDFPage() { return m_pPDFPage; }
-  CXFA_FFPageView* GetXFAPageView() { return m_pXFAPageView; }
+  CPDFXFA_Document* GetDocument() const { return m_pDocument; }
+  int GetPageIndex() const { return m_iPageIndex; }
+  CPDF_Page* GetPDFPage() const { return m_pPDFPage.get(); }
+  CXFA_FFPageView* GetXFAPageView() const { return m_pXFAPageView; }
+
   void SetXFAPageView(CXFA_FFPageView* pPageView) {
     m_pXFAPageView = pPageView;
   }
 
-  FX_FLOAT GetPageWidth();
-  FX_FLOAT GetPageHeight();
+  FX_FLOAT GetPageWidth() const;
+  FX_FLOAT GetPageHeight() const;
 
   void DeviceToPage(int start_x,
                     int start_y,
@@ -63,14 +66,17 @@ class CPDFXFA_Page {
                         int iRotate) const;
 
  protected:
+  // Refcounted class.
+  ~CPDFXFA_Page();
+
   FX_BOOL LoadPDFPage();
   FX_BOOL LoadXFAPageView();
 
  private:
-  CPDF_Page* m_pPDFPage;
+  std::unique_ptr<CPDF_Page> m_pPDFPage;
   CXFA_FFPageView* m_pXFAPageView;
-  int m_iPageIndex;
-  CPDFXFA_Document* m_pDocument;
+  CPDFXFA_Document* const m_pDocument;
+  const int m_iPageIndex;
   int m_iRef;
 };