Adjust null object check

core/src/fpdfdoc/doc_formfield.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/fpdfdoc/fpdf_doc.h"
 CFX_WideString          GetFullName(CPDF_Dictionary* pFieldDict);
 void                            SaveCheckedFieldStatus(CPDF_FormField* pField, CFX_ByteArray& statusArray);
 FX_BOOL PDF_FormField_IsUnison(CPDF_FormField *pField)
@@ skipping 1059 matching lines @@
         }
         if (GetType() == ComboBox) {
             m_pForm->m_pFormNotify->AfterValueChange(this);
         }
     }
     m_pForm->m_bUpdated = TRUE;
     return TRUE;
 }
 void CPDF_FormField::LoadDA()
 {
-    CFX_ByteString DA = FPDF_GetFieldAttr(m_pDict, "DA") ? FPDF_GetFieldAttr(m_pDict, "DA")->GetString() : CFX_ByteString();
-    if (DA.IsEmpty()) {
-        DA = m_pForm->m_pFormDict ? m_pForm->m_pFormDict->GetString("DA") : CFX_ByteString();
+    if (!m_pForm->m_pFormDict) {
+        return;
+    }
+    CFX_ByteString DA;
+    CPDF_Object* pObj_t = FPDF_GetFieldAttr(m_pDict, "DA");
+    if (pObj_t) {

[Nico, 2014/07/21 05:07:53]

You can write

  if (CPDF_Object* pObj_t = FPDF_GetFieldAttr(m_pDict, "DA")) {

here too.

+        DA = pObj_t->GetString();
     }

[Nico, 2014/07/21 05:07:53]

This is different from the previous code as far as I can tell. I think you want
a

  if (DA.isEmpty()) {
    DA = m_pForm->m_pFormDict->GetString("DA");
  }

here.

Actually, I'd write this as

  if (DA.isEmpty() && m_pForm->m_pFormDict) {
      DA = m_pForm->m_pFormDict->GetString("DA");
  }

and omit the early return that you added at the top.

[Bo Xu, 2014/07/21 16:40:44]

Done.

     if (DA.IsEmpty()) {
         return;
     }
     CPDF_SimpleParser syntax(DA);
     syntax.FindTagParam("Tf", 2);
     CFX_ByteString font_name = syntax.GetWord();
     CPDF_Dictionary* pFontDict = NULL;
     if (m_pForm->m_pFormDict && m_pForm->m_pFormDict->GetDict("DR") &&
         m_pForm->m_pFormDict->GetDict("DR")->GetDict("Font") )
     pFontDict = m_pForm->m_pFormDict->GetDict("DR")->GetDict("Font")->GetDict(font_name);
 
     if (pFontDict == NULL) {
         return;
     }
     m_pFont = m_pForm->m_pDocument->LoadFont(pFontDict);
     m_FontSize = FX_atof(syntax.GetWord());
 }