Get rid of most instance of 'foo == NULL'

core/src/fpdfdoc/doc_tagged.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 "core/include/fpdfapi/fpdf_page.h"
 #include "core/include/fpdfapi/fpdf_parser.h"
 #include "core/include/fpdfdoc/fpdf_tagged.h"
 #include "tagged_int.h"
@@ skipping 17 matching lines @@
   if (!IsTagged(pDoc)) {
     return NULL;
   }
   CPDF_StructTreeImpl* pTree = new CPDF_StructTreeImpl(pDoc);
   pTree->LoadDocTree();
   return pTree;
 }
 CPDF_StructTreeImpl::CPDF_StructTreeImpl(const CPDF_Document* pDoc) {
   CPDF_Dictionary* pCatalog = pDoc->GetRoot();
   m_pTreeRoot = pCatalog->GetDict("StructTreeRoot");
-  if (m_pTreeRoot == NULL) {
+  if (!m_pTreeRoot) {
     return;
   }
   m_pRoleMap = m_pTreeRoot->GetDict("RoleMap");
 }
 CPDF_StructTreeImpl::~CPDF_StructTreeImpl() {
   for (int i = 0; i < m_Kids.GetSize(); i++)
     if (m_Kids[i]) {
       m_Kids[i]->Release();
     }
 }
@@ skipping 39 matching lines @@
   else
     return;
 
   FX_DWORD i;
   m_Kids.SetSize(dwKids);
   for (i = 0; i < dwKids; i++) {
     m_Kids[i] = NULL;
   }
   CFX_MapPtrToPtr element_map;
   CPDF_Dictionary* pParentTree = m_pTreeRoot->GetDict("ParentTree");
-  if (pParentTree == NULL) {
+  if (!pParentTree) {
     return;
   }
   CPDF_NumberTree parent_tree(pParentTree);
   int parents_id = pPageDict->GetInteger("StructParents", -1);
   if (parents_id >= 0) {
     CPDF_Array* pParentArray = ToArray(parent_tree.LookupValue(parents_id));
     if (!pParentArray)
       return;
 
     for (i = 0; i < pParentArray->GetCount(); i++) {
       CPDF_Dictionary* pParent = pParentArray->GetDict(i);
-      if (pParent == NULL) {
+      if (!pParent) {
         continue;
       }
       AddPageNode(pParent, element_map);
     }
   }
 }
 CPDF_StructElementImpl* CPDF_StructTreeImpl::AddPageNode(CPDF_Dictionary* pDict,
                                                          CFX_MapPtrToPtr& map,
                                                          int nLevel) {
   if (nLevel > nMaxRecursion) {
     return NULL;
   }
   CPDF_StructElementImpl* pElement = NULL;
   if (map.Lookup(pDict, (void*&)pElement)) {
     return pElement;
   }
   pElement = new CPDF_StructElementImpl(this, NULL, pDict);
   map.SetAt(pDict, pElement);
   CPDF_Dictionary* pParent = pDict->GetDict("P");
-  if (pParent == NULL || pParent->GetString("Type") == "StructTreeRoot") {
+  if (!pParent || pParent->GetString("Type") == "StructTreeRoot") {
     if (!AddTopLevelNode(pDict, pElement)) {
       pElement->Release();
       map.RemoveKey(pDict);
     }
   } else {
     CPDF_StructElementImpl* pParentElement =
         AddPageNode(pParent, map, nLevel + 1);
     FX_BOOL bSave = FALSE;
     for (int i = 0; i < pParentElement->m_Kids.GetSize(); i++) {
       if (pParentElement->m_Kids[i].m_Type != CPDF_StructKid::Element) {
@@ skipping 146 matching lines @@
     pKid->m_Type = CPDF_StructKid::Object;
     if (CPDF_Reference* pObj = ToReference(pKidDict->GetElement("Obj"))) {
       pKid->m_Object.m_RefObjNum = pObj->GetRefObjNum();
     } else {
       pKid->m_Object.m_RefObjNum = 0;
     }
     pKid->m_Object.m_PageObjNum = PageObjNum;
   } else {
     pKid->m_Type = CPDF_StructKid::Element;
     pKid->m_Element.m_pDict = pKidDict;
-    if (m_pTree->m_pPage == NULL) {
+    if (!m_pTree->m_pPage) {
       pKid->m_Element.m_pElement =
           new CPDF_StructElementImpl(m_pTree, this, pKidDict);
     } else {
       pKid->m_Element.m_pElement = NULL;
     }
   }
 }
 static CPDF_Dictionary* FindAttrDict(CPDF_Object* pAttrs,
                                      const CFX_ByteStringC& owner,
                                      FX_FLOAT nLevel = 0.0F) {
@@ skipping 24 matching lines @@
                                              FX_BOOL bInheritable,
                                              FX_FLOAT fLevel) {
   if (fLevel > nMaxRecursion) {
     return NULL;
   }
   if (bInheritable) {
     CPDF_Object* pAttr = GetAttr(owner, name, FALSE);
     if (pAttr) {
       return pAttr;
     }
-    if (m_pParent == NULL) {
+    if (!m_pParent) {
       return NULL;
     }
     return m_pParent->GetAttr(owner, name, TRUE, fLevel + 1);
   }
   CPDF_Object* pA = m_pDict->GetElementValue("A");
   if (pA) {
     CPDF_Dictionary* pAttrDict = FindAttrDict(pA, owner);
     if (pAttrDict) {
       CPDF_Object* pAttr = pAttrDict->GetElementValue(name);
       if (pAttr) {
@@ skipping 70 matching lines @@
   return ToNumber(pAttr) ? pAttr->GetNumber() : default_value;
 }
 int CPDF_StructElementImpl::GetInteger(const CFX_ByteStringC& owner,
                                        const CFX_ByteStringC& name,
                                        int default_value,
                                        FX_BOOL bInheritable,
                                        int subindex) {
   CPDF_Object* pAttr = GetAttr(owner, name, bInheritable, subindex);
   return ToNumber(pAttr) ? pAttr->GetInteger() : default_value;
 }