Remove "this==NULL" and adjust corresponding callers

BUG=
R=thakis@chromium.org

Review URL: https://codereview.chromium.org/361553002

4 files changed, 33 insertions, 24 deletions

diff --git a/core/src/fpdfdoc/doc_annot.cpp b/core/src/fpdfdoc/doc_annot.cpp
index 227578a974..8952845570 100644
--- a/core/src/fpdfdoc/doc_annot.cpp
+++ b/core/src/fpdfdoc/doc_annot.cpp
@@ -165,7 +165,7 @@ void CPDF_Annot::ClearCachedAP()
 }
 CFX_ByteString CPDF_Annot::GetSubType() const
 {
-    return m_pAnnotDict->GetConstString(FX_BSTRC("Subtype"));
+    return m_pAnnotDict ? m_pAnnotDict->GetConstString(FX_BSTRC("Subtype")) : CFX_ByteStringC();
 }
 void CPDF_Annot::GetRect(CPDF_Rect& rect) const
 {
@@ -202,7 +202,8 @@ CPDF_Stream* FPDFDOC_GetAnnotAP(CPDF_Dictionary* pAnnotDict, CPDF_Annot::Appeara
         if (as.IsEmpty()) {
             CFX_ByteString value = pAnnotDict->GetString(FX_BSTRC("V"));
             if (value.IsEmpty()) {
-                value = pAnnotDict->GetDict(FX_BSTRC("Parent"))->GetString(FX_BSTRC("V"));
+                CPDF_Dictionary* pDict = pAnnotDict->GetDict(FX_BSTRC("Parent"));
+                value = pDict ? pDict->GetString(FX_BSTRC("V")) : CFX_ByteString();
             }
             if (value.IsEmpty() || !((CPDF_Dictionary*)psub)->KeyExist(value)) {
                 as = FX_BSTRC("Off");
diff --git a/core/src/fpdfdoc/doc_ap.cpp b/core/src/fpdfdoc/doc_ap.cpp
index 784d89daed..6a8ab374d2 100644
--- a/core/src/fpdfdoc/doc_ap.cpp
+++ b/core/src/fpdfdoc/doc_ap.cpp
@@ -10,11 +10,11 @@
 #include "../../include/fpdfdoc/fpdf_ap.h"
 FX_BOOL FPDF_GenerateAP(CPDF_Document* pDoc, CPDF_Dictionary* pAnnotDict)
 {
-    if (pAnnotDict->GetConstString("Subtype") != FX_BSTRC("Widget")) {
+    if (!pAnnotDict || pAnnotDict->GetConstString("Subtype") != FX_BSTRC("Widget")) {
         return FALSE;
     }
     CFX_ByteString field_type = FPDF_GetFieldAttr(pAnnotDict, "FT")->GetString();
-    FX_DWORD flags = FPDF_GetFieldAttr(pAnnotDict, "Ff")->GetInteger();
+    FX_DWORD flags = FPDF_GetFieldAttr(pAnnotDict, "Ff")? FPDF_GetFieldAttr(pAnnotDict, "Ff")->GetInteger() : 0;
     if (field_type == "Tx") {
         return CPVT_GenerateAP::GenerateTextFieldAP(pDoc, pAnnotDict);
     } else if (field_type == "Ch") {
@@ -253,7 +253,7 @@ static FX_BOOL GenerateWidgetAP(CPDF_Document* pDoc, CPDF_Dictionary* pAnnotDict
     if (!pFormDict) {
         return FALSE;
     }
-    CFX_ByteString DA = FPDF_GetFieldAttr(pAnnotDict, "DA")->GetString();
+    CFX_ByteString DA = FPDF_GetFieldAttr(pAnnotDict, "DA") ? FPDF_GetFieldAttr(pAnnotDict, "DA")->GetString() : CFX_ByteString();
     if (DA.IsEmpty()) {
         DA = pFormDict->GetString("DA");
     }
@@ -277,7 +277,7 @@ static FX_BOOL GenerateWidgetAP(CPDF_Document* pDoc, CPDF_Dictionary* pAnnotDict
         bUseFormRes = TRUE;
     }
     CPDF_Dictionary * pDRFontDict = NULL;
-    if ((pDRFontDict = pDRDict->GetDict("Font"))) {
+    if (pDRDict && (pDRFontDict = pDRDict->GetDict("Font"))) {
         pFontDict = pDRFontDict->GetDict(sFontName.Mid(1));
         if (!pFontDict && !bUseFormRes) {
             pDRDict = pFormDict->GetDict(FX_BSTRC("DR"));
@@ -430,11 +430,11 @@ static FX_BOOL GenerateWidgetAP(CPDF_Document* pDoc, CPDF_Dictionary* pAnnotDict
     }
     switch (nWidgetType) {
         case 0: {
-                CFX_WideString swValue = FPDF_GetFieldAttr(pAnnotDict, "V")->GetUnicodeText();
-                FX_INT32 nAlign = FPDF_GetFieldAttr(pAnnotDict, "Q")->GetInteger();
-                FX_DWORD dwFlags = FPDF_GetFieldAttr(pAnnotDict, "Ff")->GetInteger();
-                FX_DWORD dwMaxLen = FPDF_GetFieldAttr(pAnnotDict, "MaxLen")->GetInteger();
-                CPVT_FontMap map(pDoc, pStreamDict->GetDict("Resources"), pDefFont, sFontName.Right(sFontName.GetLength() - 1));
+                CFX_WideString swValue = FPDF_GetFieldAttr(pAnnotDict, "V")? FPDF_GetFieldAttr(pAnnotDict, "V")->GetUnicodeText() : CFX_WideString();
+                FX_INT32 nAlign = FPDF_GetFieldAttr(pAnnotDict, "Q")? FPDF_GetFieldAttr(pAnnotDict, "Q")->GetInteger() : 0;
+                FX_DWORD dwFlags = FPDF_GetFieldAttr(pAnnotDict, "Ff")? FPDF_GetFieldAttr(pAnnotDict, "Ff")->GetInteger() : 0;
+                FX_DWORD dwMaxLen = FPDF_GetFieldAttr(pAnnotDict, "MaxLen") ? FPDF_GetFieldAttr(pAnnotDict, "MaxLen")->GetInteger() : 0;
+                CPVT_FontMap map(pDoc, pStreamDict ? pStreamDict->GetDict("Resources") : NULL , pDefFont, sFontName.Right(sFontName.GetLength() - 1));
                 CPVT_Provider prd(&map);
                 CPDF_VariableText vt;
                 vt.SetProvider(&prd);
@@ -482,8 +482,8 @@ static FX_BOOL GenerateWidgetAP(CPDF_Document* pDoc, CPDF_Dictionary* pAnnotDict
             }
             break;
         case 1: {
-                CFX_WideString swValue = FPDF_GetFieldAttr(pAnnotDict, "V")->GetUnicodeText();
-                CPVT_FontMap map(pDoc, pStreamDict->GetDict("Resources"), pDefFont, sFontName.Right(sFontName.GetLength() - 1));
+                CFX_WideString swValue = FPDF_GetFieldAttr(pAnnotDict, "V") ? FPDF_GetFieldAttr(pAnnotDict, "V")->GetUnicodeText() : CFX_WideString();
+                CPVT_FontMap map(pDoc, pStreamDict ? pStreamDict->GetDict("Resources"):NULL, pDefFont, sFontName.Right(sFontName.GetLength() - 1));
                 CPVT_Provider prd(&map);
                 CPDF_VariableText vt;
                 vt.SetProvider(&prd);
@@ -534,11 +534,11 @@ static FX_BOOL GenerateWidgetAP(CPDF_Document* pDoc, CPDF_Dictionary* pAnnotDict
             }
             break;
         case 2: {
-                CPVT_FontMap map(pDoc, pStreamDict->GetDict("Resources"), pDefFont, sFontName.Right(sFontName.GetLength() - 1));
+                CPVT_FontMap map(pDoc, pStreamDict ? pStreamDict->GetDict("Resources"):NULL, pDefFont, sFontName.Right(sFontName.GetLength() - 1));
                 CPVT_Provider prd(&map);
-                CPDF_Array * pOpts = FPDF_GetFieldAttr(pAnnotDict, "Opt")->GetArray();
-                CPDF_Array * pSels = FPDF_GetFieldAttr(pAnnotDict, "I")->GetArray();
-                FX_INT32 nTop = FPDF_GetFieldAttr(pAnnotDict, "TI")->GetInteger();
+                CPDF_Array * pOpts = FPDF_GetFieldAttr(pAnnotDict, "Opt") ? FPDF_GetFieldAttr(pAnnotDict, "Opt")->GetArray() : NULL;
+                CPDF_Array * pSels = FPDF_GetFieldAttr(pAnnotDict, "I") ? FPDF_GetFieldAttr(pAnnotDict, "I")->GetArray() : NULL;
+                FX_INT32 nTop = FPDF_GetFieldAttr(pAnnotDict, "TI") ? FPDF_GetFieldAttr(pAnnotDict, "TI")->GetInteger() : 0;
                 CFX_ByteTextBuf sBody;
                 if (pOpts) {
                     FX_FLOAT fy = rcBody.top;
diff --git a/core/src/fpdfdoc/doc_basic.cpp b/core/src/fpdfdoc/doc_basic.cpp
index 199a9a6dec..25f641c52e 100644
--- a/core/src/fpdfdoc/doc_basic.cpp
+++ b/core/src/fpdfdoc/doc_basic.cpp
@@ -72,7 +72,10 @@ CFX_ByteString CPDF_Dest::GetRemoteName()
 }
 CPDF_NameTree::CPDF_NameTree(CPDF_Document* pDoc, FX_BSTR category)
 {
-    m_pRoot = pDoc->GetRoot()->GetDict(FX_BSTRC("Names"))->GetDict(category);
+    if (pDoc->GetRoot() && pDoc->GetRoot()->GetDict(FX_BSTRC("Names")))
+        m_pRoot = pDoc->GetRoot()->GetDict(FX_BSTRC("Names"))->GetDict(category);
+    else
+        m_pRoot = NULL;
 }
 static CPDF_Object* SearchNameNode(CPDF_Dictionary* pNode, const CFX_ByteString& csName,
                                    int& nIndex, CPDF_Array** ppFind, int nLevel = 0)
diff --git a/core/src/fpdfdoc/doc_formfield.cpp b/core/src/fpdfdoc/doc_formfield.cpp
index 548448696d..e51acf94a1 100644
--- a/core/src/fpdfdoc/doc_formfield.cpp
+++ b/core/src/fpdfdoc/doc_formfield.cpp
@@ -32,8 +32,8 @@ CPDF_FormField::~CPDF_FormField()
 }
 void CPDF_FormField::SyncFieldFlags()
 {
-    CFX_ByteString type_name = FPDF_GetFieldAttr(m_pDict, "FT")->GetString();
-    FX_DWORD flags = FPDF_GetFieldAttr(m_pDict, "Ff")->GetInteger();
+    CFX_ByteString type_name = FPDF_GetFieldAttr(m_pDict, "FT") ? FPDF_GetFieldAttr(m_pDict, "FT")->GetString() : CFX_ByteString();
+    FX_DWORD flags = FPDF_GetFieldAttr(m_pDict, "Ff")? FPDF_GetFieldAttr(m_pDict, "Ff")->GetInteger() : 0;
     m_Flags = 0;
     if (flags & 1) {
         m_Flags |= FORMFIELD_READONLY;
@@ -485,7 +485,8 @@ int CPDF_FormField::GetSelectedIndex(int index)
         if (index < 0) {
             return -1;
         }
-        sel_value = ((CPDF_Array*)pValue)->GetElementValue(index)->GetUnicodeText();
+        CPDF_Object* elementValue = ((CPDF_Array*)pValue)->GetElementValue(index);
+        sel_value = elementValue ? elementValue->GetUnicodeText() : CFX_WideString();
     }
     if (index < CountSelectedOptions()) {
         int iOptIndex = GetSelectedOptionIndex(index);
@@ -1076,9 +1077,9 @@ FX_BOOL CPDF_FormField::ClearSelectedOptions(FX_BOOL bNotify)
 }
 void CPDF_FormField::LoadDA()
 {
-    CFX_ByteString DA = FPDF_GetFieldAttr(m_pDict, "DA")->GetString();
+    CFX_ByteString DA = FPDF_GetFieldAttr(m_pDict, "DA") ? FPDF_GetFieldAttr(m_pDict, "DA")->GetString() : CFX_ByteString();
     if (DA.IsEmpty()) {
-        DA = m_pForm->m_pFormDict->GetString("DA");
+        DA = m_pForm->m_pFormDict ? m_pForm->m_pFormDict->GetString("DA") : CFX_ByteString();
     }
     if (DA.IsEmpty()) {
         return;
@@ -1086,7 +1087,11 @@ void CPDF_FormField::LoadDA()
     CPDF_SimpleParser syntax(DA);
     syntax.FindTagParam("Tf", 2);
     CFX_ByteString font_name = syntax.GetWord();
-    CPDF_Dictionary* pFontDict = m_pForm->m_pFormDict->GetDict("DR")->GetDict("Font")->GetDict(font_name);
+    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;
     }