Get rid of NULLs in fpdfsdk/

Review-Url: https://codereview.chromium.org/2031653003

64 files changed, 359 insertions, 371 deletions

diff --git a/core/fxcodec/codec/fx_codec_jpx_unittest.cpp b/core/fxcodec/codec/fx_codec_jpx_unittest.cpp
index 13b5425927..820a618f5b 100644
--- a/core/fxcodec/codec/fx_codec_jpx_unittest.cpp
+++ b/core/fxcodec/codec/fx_codec_jpx_unittest.cpp
@@ -23,7 +23,7 @@ TEST(fxcodec, DecodeDataNullDecodeData) {
   unsigned char buffer[16];
   DecodeData* ptr = nullptr;
 
-  // Error codes, not segvs, should callers pass us a NULL pointer.
+  // Error codes, not segvs, should callers pass us a nullptr pointer.
   EXPECT_EQ(kReadError, opj_read_from_memory(buffer, sizeof(buffer), ptr));
   EXPECT_EQ(kWriteError, opj_write_from_memory(buffer, sizeof(buffer), ptr));
   EXPECT_EQ(kSkipError, opj_skip_from_memory(1, ptr));
diff --git a/core/fxcrt/fx_basic_bstring_unittest.cpp b/core/fxcrt/fx_basic_bstring_unittest.cpp
index 220105aa95..cfdf2794b4 100644
--- a/core/fxcrt/fx_basic_bstring_unittest.cpp
+++ b/core/fxcrt/fx_basic_bstring_unittest.cpp
@@ -758,7 +758,7 @@ TEST(fxcrt, ByteStringCFromChar) {
   CFX_ByteStringC nul_string_from_char(nul);
   CFX_ByteStringC lower_a_string_from_char(lower_a);
 
-  // Pointer to nul, not NULL ptr, hence length 1 ...
+  // Pointer to nul, not nullptr ptr, hence length 1 ...
   EXPECT_EQ(1, nul_string_from_char.GetLength());
   EXPECT_NE(null_string, nul_string_from_char);
 
diff --git a/core/fxcrt/include/fx_memory.h b/core/fxcrt/include/fx_memory.h
index 3048897d76..fa8da6067c 100644
--- a/core/fxcrt/include/fx_memory.h
+++ b/core/fxcrt/include/fx_memory.h
@@ -13,7 +13,7 @@
 extern "C" {
 #endif
 
-// For external C libraries to malloc through PDFium. These may return NULL.
+// For external C libraries to malloc through PDFium. These may return nullptr.
 void* FXMEM_DefaultAlloc(size_t byte_size, int flags);
 void* FXMEM_DefaultRealloc(void* pointer, size_t new_size, int flags);
 void FXMEM_DefaultFree(void* pointer, int flags);
@@ -61,13 +61,13 @@ inline void* FX_ReallocOrDie(void* ptr,
   return nullptr;             // Suppress compiler warning.
 }
 
-// Never returns NULL.
+// Never returns nullptr.
 #define FX_Alloc(type, size) (type*) FX_AllocOrDie(size, sizeof(type))
 #define FX_Alloc2D(type, w, h) (type*) FX_AllocOrDie2D(w, h, sizeof(type))
 #define FX_Realloc(type, ptr, size) \
   (type*) FX_ReallocOrDie(ptr, size, sizeof(type))
 
-// May return NULL.
+// May return nullptr.
 #define FX_TryAlloc(type, size) (type*) calloc(size, sizeof(type))
 #define FX_TryRealloc(type, ptr, size) \
   (type*) FX_SafeRealloc(ptr, size, sizeof(type))
diff --git a/fpdfsdk/formfiller/cba_fontmap.cpp b/fpdfsdk/formfiller/cba_fontmap.cpp
index 4c74d5a242..9102b7bf9a 100644
--- a/fpdfsdk/formfiller/cba_fontmap.cpp
+++ b/fpdfsdk/formfiller/cba_fontmap.cpp
@@ -16,9 +16,9 @@
 CBA_FontMap::CBA_FontMap(CPDFSDK_Annot* pAnnot,
                          CFX_SystemHandler* pSystemHandler)
     : CPWL_FontMap(pSystemHandler),
-      m_pDocument(NULL),
-      m_pAnnotDict(NULL),
-      m_pDefaultFont(NULL),
+      m_pDocument(nullptr),
+      m_pAnnotDict(nullptr),
+      m_pDefaultFont(nullptr),
       m_sAPType("N") {
   CPDF_Page* pPage = pAnnot->GetPDFPage();
 
@@ -31,7 +31,7 @@ CBA_FontMap::~CBA_FontMap() {}
 
 void CBA_FontMap::Reset() {
   Empty();
-  m_pDefaultFont = NULL;
+  m_pDefaultFont = nullptr;
   m_sDefaultFontName = "";
 }
 
@@ -83,20 +83,20 @@ CPDF_Font* CBA_FontMap::FindFontSameCharset(CFX_ByteString& sFontAlias,
     CPDF_Document* pDocument = GetDocument();
     CPDF_Dictionary* pRootDict = pDocument->GetRoot();
     if (!pRootDict)
-      return NULL;
+      return nullptr;
 
     CPDF_Dictionary* pAcroFormDict = pRootDict->GetDictBy("AcroForm");
     if (!pAcroFormDict)
-      return NULL;
+      return nullptr;
 
     CPDF_Dictionary* pDRDict = pAcroFormDict->GetDictBy("DR");
     if (!pDRDict)
-      return NULL;
+      return nullptr;
 
     return FindResFontSameCharset(pDRDict, sFontAlias, nCharset);
   }
 
-  return NULL;
+  return nullptr;
 }
 
 CPDF_Document* CBA_FontMap::GetDocument() {
@@ -107,14 +107,14 @@ CPDF_Font* CBA_FontMap::FindResFontSameCharset(CPDF_Dictionary* pResDict,
                                                CFX_ByteString& sFontAlias,
                                                int32_t nCharset) {
   if (!pResDict)
-    return NULL;
+    return nullptr;
 
   CPDF_Dictionary* pFonts = pResDict->GetDictBy("Font");
   if (!pFonts)
-    return NULL;
+    return nullptr;
 
   CPDF_Document* pDocument = GetDocument();
-  CPDF_Font* pFind = NULL;
+  CPDF_Font* pFind = nullptr;
   for (const auto& it : *pFonts) {
     const CFX_ByteString& csKey = it.first;
     CPDF_Object* pObj = it.second;
@@ -165,7 +165,7 @@ void CBA_FontMap::AddFontToAnnotDict(CPDF_Font* pFont,
 
   CPDF_Stream* pStream = pAPDict->GetStreamBy(m_sAPType);
   if (!pStream) {
-    pStream = new CPDF_Stream(NULL, 0, NULL);
+    pStream = new CPDF_Stream(nullptr, 0, nullptr);
     int32_t objnum = m_pDocument->AddIndirectObject(pStream);
     pAPDict->SetAtReference(m_sAPType, m_pDocument, objnum);
   }
@@ -174,7 +174,7 @@ void CBA_FontMap::AddFontToAnnotDict(CPDF_Font* pFont,
 
   if (!pStreamDict) {
     pStreamDict = new CPDF_Dictionary;
-    pStream->InitStream(NULL, 0, pStreamDict);
+    pStream->InitStream(nullptr, 0, pStreamDict);
   }
 
   if (pStreamDict) {
@@ -199,7 +199,7 @@ void CBA_FontMap::AddFontToAnnotDict(CPDF_Font* pFont,
 }
 
 CPDF_Font* CBA_FontMap::GetAnnotDefaultFont(CFX_ByteString& sAlias) {
-  CPDF_Dictionary* pAcroFormDict = NULL;
+  CPDF_Dictionary* pAcroFormDict = nullptr;
   const bool bWidget = (m_pAnnotDict->GetStringBy("Subtype") == "Widget");
   if (bWidget) {
     if (CPDF_Dictionary* pRootDict = m_pDocument->GetRoot())
@@ -218,7 +218,7 @@ CPDF_Font* CBA_FontMap::GetAnnotDefaultFont(CFX_ByteString& sAlias) {
     }
   }
 
-  CPDF_Dictionary* pFontDict = NULL;
+  CPDF_Dictionary* pFontDict = nullptr;
 
   if (!sDA.IsEmpty()) {
     CPDF_SimpleParser syntax(sDA.AsStringC());
diff --git a/fpdfsdk/formfiller/cffl_combobox.cpp b/fpdfsdk/formfiller/cffl_combobox.cpp
index 8b2da626b2..d489a243d9 100644
--- a/fpdfsdk/formfiller/cffl_combobox.cpp
+++ b/fpdfsdk/formfiller/cffl_combobox.cpp
@@ -14,7 +14,7 @@
 #include "fpdfsdk/pdfwindow/PWL_ComboBox.h"
 
 CFFL_ComboBox::CFFL_ComboBox(CPDFDoc_Environment* pApp, CPDFSDK_Annot* pAnnot)
-    : CFFL_FormFiller(pApp, pAnnot), m_pFontMap(NULL) {
+    : CFFL_FormFiller(pApp, pAnnot), m_pFontMap(nullptr) {
   m_State.nIndex = 0;
   m_State.nStart = 0;
   m_State.nEnd = 0;
@@ -227,7 +227,7 @@ CPWL_Wnd* CFFL_ComboBox::ResetPDFWindow(CPDFSDK_PageView* pPageView,
 
   DestroyPDFWindow(pPageView);
 
-  CPWL_Wnd* pRet = NULL;
+  CPWL_Wnd* pRet = nullptr;
 
   if (bRestoreValue) {
     RestoreState(pPageView);
diff --git a/fpdfsdk/formfiller/cffl_formfiller.cpp b/fpdfsdk/formfiller/cffl_formfiller.cpp
index 8ee6da387d..d7bc9586a4 100644
--- a/fpdfsdk/formfiller/cffl_formfiller.cpp
+++ b/fpdfsdk/formfiller/cffl_formfiller.cpp
@@ -88,7 +88,8 @@ void CFFL_FormFiller::OnDraw(CPDFSDK_PageView* pPageView,
   } else {
     CPDFSDK_Widget* pWidget = (CPDFSDK_Widget*)pAnnot;
     if (CFFL_IFormFiller::IsVisible(pWidget))
-      pWidget->DrawAppearance(pDevice, pUser2Device, CPDF_Annot::Normal, NULL);
+      pWidget->DrawAppearance(pDevice, pUser2Device, CPDF_Annot::Normal,
+                              nullptr);
   }
 }
 
@@ -98,7 +99,7 @@ void CFFL_FormFiller::OnDrawDeactive(CPDFSDK_PageView* pPageView,
                                      CFX_Matrix* pUser2Device,
                                      uint32_t dwFlags) {
   CPDFSDK_Widget* pWidget = (CPDFSDK_Widget*)pAnnot;
-  pWidget->DrawAppearance(pDevice, pUser2Device, CPDF_Annot::Normal, NULL);
+  pWidget->DrawAppearance(pDevice, pUser2Device, CPDF_Annot::Normal, nullptr);
 }
 
 void CFFL_FormFiller::OnCreate(CPDFSDK_Annot* pAnnot) {}
@@ -293,7 +294,7 @@ PWL_CREATEPARAM CFFL_FormFiller::GetCreateParam() {
   ASSERT(m_pApp);
 
   PWL_CREATEPARAM cp;
-  cp.pParentWnd = NULL;
+  cp.pParentWnd = nullptr;
   cp.pProvider = this;
   cp.rcRectWnd = GetPDFWindowRect();
 
@@ -690,23 +691,25 @@ void CFFL_Button::OnDraw(CPDFSDK_PageView* pPageView,
   CPDF_FormControl::HighlightingMode eHM = pCtrl->GetHighlightingMode();
 
   if (eHM != CPDF_FormControl::Push) {
-    pWidget->DrawAppearance(pDevice, pUser2Device, CPDF_Annot::Normal, NULL);
+    pWidget->DrawAppearance(pDevice, pUser2Device, CPDF_Annot::Normal, nullptr);
     return;
   }
 
   if (m_bMouseDown) {
     if (pWidget->IsWidgetAppearanceValid(CPDF_Annot::Down))
-      pWidget->DrawAppearance(pDevice, pUser2Device, CPDF_Annot::Down, NULL);
+      pWidget->DrawAppearance(pDevice, pUser2Device, CPDF_Annot::Down, nullptr);
     else
-      pWidget->DrawAppearance(pDevice, pUser2Device, CPDF_Annot::Normal, NULL);
+      pWidget->DrawAppearance(pDevice, pUser2Device, CPDF_Annot::Normal,
+                              nullptr);
   } else if (m_bMouseIn) {
     if (pWidget->IsWidgetAppearanceValid(CPDF_Annot::Rollover))
       pWidget->DrawAppearance(pDevice, pUser2Device, CPDF_Annot::Rollover,
-                              NULL);
+                              nullptr);
     else
-      pWidget->DrawAppearance(pDevice, pUser2Device, CPDF_Annot::Normal, NULL);
+      pWidget->DrawAppearance(pDevice, pUser2Device, CPDF_Annot::Normal,
+                              nullptr);
   } else {
-    pWidget->DrawAppearance(pDevice, pUser2Device, CPDF_Annot::Normal, NULL);
+    pWidget->DrawAppearance(pDevice, pUser2Device, CPDF_Annot::Normal, nullptr);
   }
 }
 
diff --git a/fpdfsdk/formfiller/cffl_iformfiller.cpp b/fpdfsdk/formfiller/cffl_iformfiller.cpp
index 9dcc734a24..107197fa72 100644
--- a/fpdfsdk/formfiller/cffl_iformfiller.cpp
+++ b/fpdfsdk/formfiller/cffl_iformfiller.cpp
@@ -97,7 +97,7 @@ void CFFL_IFormFiller::OnDraw(CPDFSDK_PageView* pPageView,
     pFormFiller->OnDrawDeactive(pPageView, pAnnot, pDevice, pUser2Device,
                                 dwFlags);
   } else {
-    pWidget->DrawAppearance(pDevice, pUser2Device, CPDF_Annot::Normal, NULL);
+    pWidget->DrawAppearance(pDevice, pUser2Device, CPDF_Annot::Normal, nullptr);
   }
 
   if (!IsReadOnly(pWidget) && IsFillingAllowed(pWidget))
diff --git a/fpdfsdk/formfiller/cffl_listbox.cpp b/fpdfsdk/formfiller/cffl_listbox.cpp
index dc4f07d0d2..cbac83cb55 100644
--- a/fpdfsdk/formfiller/cffl_listbox.cpp
+++ b/fpdfsdk/formfiller/cffl_listbox.cpp
@@ -16,7 +16,7 @@
 #define FFL_DEFAULTLISTBOXFONTSIZE 12.0f
 
 CFFL_ListBox::CFFL_ListBox(CPDFDoc_Environment* pApp, CPDFSDK_Annot* pWidget)
-    : CFFL_FormFiller(pApp, pWidget), m_pFontMap(NULL) {}
+    : CFFL_FormFiller(pApp, pWidget), m_pFontMap(nullptr) {}
 
 CFFL_ListBox::~CFFL_ListBox() {
   delete m_pFontMap;
@@ -193,7 +193,7 @@ CPWL_Wnd* CFFL_ListBox::ResetPDFWindow(CPDFSDK_PageView* pPageView,
 
   DestroyPDFWindow(pPageView);
 
-  CPWL_Wnd* pRet = NULL;
+  CPWL_Wnd* pRet = nullptr;
 
   if (bRestoreValue) {
     RestoreState(pPageView);
diff --git a/fpdfsdk/formfiller/cffl_textfield.cpp b/fpdfsdk/formfiller/cffl_textfield.cpp
index 7399651234..be1f36b697 100644
--- a/fpdfsdk/formfiller/cffl_textfield.cpp
+++ b/fpdfsdk/formfiller/cffl_textfield.cpp
@@ -11,7 +11,7 @@
 #include "fpdfsdk/include/fsdk_mgr.h"
 
 CFFL_TextField::CFFL_TextField(CPDFDoc_Environment* pApp, CPDFSDK_Annot* pAnnot)
-    : CFFL_FormFiller(pApp, pAnnot), m_pFontMap(NULL) {
+    : CFFL_FormFiller(pApp, pAnnot), m_pFontMap(nullptr) {
   m_State.nStart = m_State.nEnd = 0;
 }
 
@@ -30,9 +30,6 @@ PWL_CREATEPARAM CFFL_TextField::GetCreateParam() {
     cp.dwFlags |= PES_PASSWORD;
   }
 
-  if (!(nFlags & FIELDFLAG_DONOTSPELLCHECK)) {
-  }
-
   if (nFlags & FIELDFLAG_MULTILINE) {
     cp.dwFlags |= PES_MULTILINE | PES_AUTORETURN | PES_TOP;
 
@@ -244,7 +241,7 @@ CPWL_Wnd* CFFL_TextField::ResetPDFWindow(CPDFSDK_PageView* pPageView,
 
   DestroyPDFWindow(pPageView);
 
-  CPWL_Wnd* pRet = NULL;
+  CPWL_Wnd* pRet = nullptr;
 
   if (bRestoreValue) {
     RestoreState(pPageView);
diff --git a/fpdfsdk/fpdf_dataavail.cpp b/fpdfsdk/fpdf_dataavail.cpp
index dc6efbc436..878271efc9 100644
--- a/fpdfsdk/fpdf_dataavail.cpp
+++ b/fpdfsdk/fpdf_dataavail.cpp
@@ -37,7 +37,7 @@ static_assert(IPDF_DataAvail::FormNotExist == PDF_FORM_NOTEXIST,
 
 class CFPDF_FileAvailWrap : public IPDF_DataAvail::FileAvail {
  public:
-  CFPDF_FileAvailWrap() { m_pfileAvail = NULL; }
+  CFPDF_FileAvailWrap() { m_pfileAvail = nullptr; }
   ~CFPDF_FileAvailWrap() override {}
 
   void Set(FX_FILEAVAIL* pfileAvail) { m_pfileAvail = pfileAvail; }
@@ -53,7 +53,7 @@ class CFPDF_FileAvailWrap : public IPDF_DataAvail::FileAvail {
 
 class CFPDF_FileAccessWrap : public IFX_FileRead {
  public:
-  CFPDF_FileAccessWrap() { m_pFileAccess = NULL; }
+  CFPDF_FileAccessWrap() { m_pFileAccess = nullptr; }
   ~CFPDF_FileAccessWrap() override {}
 
   void Set(FPDF_FILEACCESS* pFile) { m_pFileAccess = pFile; }
@@ -91,7 +91,7 @@ class CFPDF_DownloadHintsWrap : public IPDF_DataAvail::DownloadHints {
 
 class CFPDF_DataAvail {
  public:
-  CFPDF_DataAvail() { m_pDataAvail = NULL; }
+  CFPDF_DataAvail() { m_pDataAvail = nullptr; }
 
   ~CFPDF_DataAvail() { delete m_pDataAvail; }
 
diff --git a/fpdfsdk/fpdf_ext.cpp b/fpdfsdk/fpdf_ext.cpp
index 0a76a0d4be..d262e3c0a5 100644
--- a/fpdfsdk/fpdf_ext.cpp
+++ b/fpdfsdk/fpdf_ext.cpp
@@ -156,7 +156,7 @@ void CheckUnSupportError(CPDF_Document* pDoc, uint32_t err_code) {
       }
       if (pNameDict && pNameDict->KeyExist("JavaScript")) {
         CPDF_Dictionary* pJSDict = pNameDict->GetDictBy("JavaScript");
-        CPDF_Array* pArray = pJSDict ? pJSDict->GetArrayBy("Names") : NULL;
+        CPDF_Array* pArray = pJSDict ? pJSDict->GetArrayBy("Names") : nullptr;
         if (pArray) {
           for (size_t i = 0; i < pArray->GetCount(); i++) {
             CFX_ByteString cbStr = pArray->GetStringAt(i);
diff --git a/fpdfsdk/fpdf_flatten.cpp b/fpdfsdk/fpdf_flatten.cpp
index 27646255c8..bc1a1ccc60 100644
--- a/fpdfsdk/fpdf_flatten.cpp
+++ b/fpdfsdk/fpdf_flatten.cpp
@@ -195,7 +195,8 @@ void SetPageContents(CFX_ByteString key,
   if (!pContentsObj) {
     // Create a new contents dictionary
     if (!key.IsEmpty()) {
-      CPDF_Stream* pNewContents = new CPDF_Stream(NULL, 0, new CPDF_Dictionary);
+      CPDF_Stream* pNewContents =
+          new CPDF_Stream(nullptr, 0, new CPDF_Dictionary);
       pPage->SetAtReference("Contents", pDocument,
                             pDocument->AddIndirectObject(pNewContents));
 
@@ -207,7 +208,7 @@ void SetPageContents(CFX_ByteString key,
     return;
   }
 
-  CPDF_Array* pContentsArray = NULL;
+  CPDF_Array* pContentsArray = nullptr;
 
   switch (pContentsObj->GetType()) {
     case CPDF_Object::STREAM: {
@@ -240,7 +241,8 @@ void SetPageContents(CFX_ByteString key,
   pPage->SetAtReference("Contents", pDocument, dwObjNum);
 
   if (!key.IsEmpty()) {
-    CPDF_Stream* pNewContents = new CPDF_Stream(NULL, 0, new CPDF_Dictionary);
+    CPDF_Stream* pNewContents =
+        new CPDF_Stream(nullptr, 0, new CPDF_Dictionary);
     dwObjNum = pDocument->AddIndirectObject(pNewContents);
     pContentsArray->AddReference(pDocument, dwObjNum);
 
@@ -377,7 +379,7 @@ DLLEXPORT int STDCALL FPDFPage_Flatten(FPDF_PAGE page, int nFlag) {
     pPageDict->SetAt("Resources", pRes);
   }
 
-  CPDF_Stream* pNewXObject = new CPDF_Stream(NULL, 0, new CPDF_Dictionary);
+  CPDF_Stream* pNewXObject = new CPDF_Stream(nullptr, 0, new CPDF_Dictionary);
   uint32_t dwObjNum = pDocument->AddIndirectObject(pNewXObject);
   CPDF_Dictionary* pPageXObject = pRes->GetDictBy("XObject");
   if (!pPageXObject) {
@@ -400,7 +402,7 @@ DLLEXPORT int STDCALL FPDFPage_Flatten(FPDF_PAGE page, int nFlag) {
 
   SetPageContents(key, pPageDict, pDocument);
 
-  CPDF_Dictionary* pNewXORes = NULL;
+  CPDF_Dictionary* pNewXORes = nullptr;
 
   if (!key.IsEmpty()) {
     pPageXObject->SetAtReference(key, pDocument, dwObjNum);
diff --git a/fpdfsdk/fpdf_sysfontinfo.cpp b/fpdfsdk/fpdf_sysfontinfo.cpp
index 9d05903a61..2a309d9785 100644
--- a/fpdfsdk/fpdf_sysfontinfo.cpp
+++ b/fpdfsdk/fpdf_sysfontinfo.cpp
@@ -36,13 +36,13 @@ class CFX_ExternalFontInfo final : public IFX_SystemFontInfo {
     if (m_pInfo->MapFont)
       return m_pInfo->MapFont(m_pInfo, weight, bItalic, charset, pitch_family,
                               family, &iExact);
-    return NULL;
+    return nullptr;
   }
 
   void* GetFont(const FX_CHAR* family) override {
     if (m_pInfo->GetFont)
       return m_pInfo->GetFont(m_pInfo, family);
-    return NULL;
+    return nullptr;
   }
 
   uint32_t GetFontData(void* hFont,
@@ -57,7 +57,7 @@ class CFX_ExternalFontInfo final : public IFX_SystemFontInfo {
   FX_BOOL GetFaceName(void* hFont, CFX_ByteString& name) override {
     if (!m_pInfo->GetFaceName)
       return FALSE;
-    uint32_t size = m_pInfo->GetFaceName(m_pInfo, hFont, NULL, 0);
+    uint32_t size = m_pInfo->GetFaceName(m_pInfo, hFont, nullptr, 0);
     if (size == 0)
       return FALSE;
     char* buffer = FX_Alloc(char, size);
diff --git a/fpdfsdk/fpdfdoc.cpp b/fpdfsdk/fpdfdoc.cpp
index 0f69340821..0cf222d796 100644
--- a/fpdfsdk/fpdfdoc.cpp
+++ b/fpdfsdk/fpdfdoc.cpp
@@ -130,7 +130,7 @@ DLLEXPORT FPDF_DEST STDCALL FPDFBookmark_GetDest(FPDF_DOCUMENT document,
 
 DLLEXPORT FPDF_ACTION STDCALL FPDFBookmark_GetAction(FPDF_BOOKMARK pDict) {
   if (!pDict)
-    return NULL;
+    return nullptr;
   CPDF_Bookmark bookmark(ToDictionary(static_cast<CPDF_Object*>(pDict)));
   return bookmark.GetAction().GetDict();
 }
diff --git a/fpdfsdk/fpdfeditimg.cpp b/fpdfsdk/fpdfeditimg.cpp
index c189f2314c..4429dcd201 100644
--- a/fpdfsdk/fpdfeditimg.cpp
+++ b/fpdfsdk/fpdfeditimg.cpp
@@ -38,7 +38,7 @@ FPDFImageObj_LoadJpegFile(FPDF_PAGE* pages,
     CPDF_Page* pPage = CPDFPageFromFPDFPage(pages[index]);
     if (!pPage)
       continue;
-    pImgObj->m_pImage->ResetCache(pPage, NULL);
+    pImgObj->m_pImage->ResetCache(pPage, nullptr);
   }
   pImgObj->m_pImage->SetJpegImage(pFile);
 
@@ -71,7 +71,7 @@ DLLEXPORT FPDF_BOOL STDCALL FPDFImageObj_SetBitmap(FPDF_PAGE* pages,
                                                    FPDF_BITMAP bitmap) {
   if (!image_object || !bitmap || !pages)
     return FALSE;
-  CFX_DIBitmap* pBmp = NULL;
+  CFX_DIBitmap* pBmp = nullptr;
   pBmp = (CFX_DIBitmap*)bitmap;
   CPDF_ImageObject* pImgObj = (CPDF_ImageObject*)image_object;
   pImgObj->m_GeneralState.GetModify();
@@ -79,7 +79,7 @@ DLLEXPORT FPDF_BOOL STDCALL FPDFImageObj_SetBitmap(FPDF_PAGE* pages,
     CPDF_Page* pPage = CPDFPageFromFPDFPage(pages[index]);
     if (!pPage)
       continue;
-    pImgObj->m_pImage->ResetCache(pPage, NULL);
+    pImgObj->m_pImage->ResetCache(pPage, nullptr);
   }
   pImgObj->m_pImage->SetImage(pBmp, FALSE);
   pImgObj->CalcBoundingBox();
diff --git a/fpdfsdk/fpdfeditpage.cpp b/fpdfsdk/fpdfeditpage.cpp
index 576d9fb778..6f71a86548 100644
--- a/fpdfsdk/fpdfeditpage.cpp
+++ b/fpdfsdk/fpdfeditpage.cpp
@@ -53,7 +53,7 @@ DLLEXPORT FPDF_DOCUMENT STDCALL FPDF_CreateNewDocument() {
     }
   }
 
-  CPDF_Dictionary* pInfoDict = NULL;
+  CPDF_Dictionary* pInfoDict = nullptr;
   pInfoDict = pDoc->GetInfo();
   if (pInfoDict) {
     if (FSDK_IsSandBoxPolicyEnabled(FPDF_POLICY_MACHINETIME_ACCESS))
@@ -84,7 +84,7 @@ DLLEXPORT FPDF_PAGE STDCALL FPDFPage_New(FPDF_DOCUMENT document,
 
   CPDF_Dictionary* pPageDict = pDoc->CreateNewPage(page_index);
   if (!pPageDict)
-    return NULL;
+    return nullptr;
   CPDF_Array* pMediaBoxArray = new CPDF_Array;
   pMediaBoxArray->Add(new CPDF_Number(0));
   pMediaBoxArray->Add(new CPDF_Number(0));
@@ -218,7 +218,7 @@ FPDFPageObj_HasTransparency(FPDF_PAGEOBJECT pageObject) {
     return TRUE;
 
   CPDF_Dictionary* pSMaskDict =
-      pGeneralState ? ToDictionary(pGeneralState->m_pSoftMask) : NULL;
+      pGeneralState ? ToDictionary(pGeneralState->m_pSoftMask) : nullptr;
   if (pSMaskDict)
     return TRUE;
 
@@ -291,8 +291,7 @@ DLLEXPORT void STDCALL FPDFPage_TransformAnnots(FPDF_PAGE page,
     CFX_Matrix 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()->GetArrayBy("Rect");
+    CPDF_Array* pRectArray = pAnnot->GetAnnotDict()->GetArrayBy("Rect");
     if (!pRectArray)
       pRectArray = new CPDF_Array;
     pRectArray->SetAt(0, new CPDF_Number(rect.left));
diff --git a/fpdfsdk/fpdfformfill.cpp b/fpdfsdk/fpdfformfill.cpp
index 2631eb3e4f..c9c2c39476 100644
--- a/fpdfsdk/fpdfformfill.cpp
+++ b/fpdfsdk/fpdfformfill.cpp
@@ -139,7 +139,7 @@ void FFLCommon(FPDF_FORMHANDLE hHandle,
   pDevice->RestoreState(false);
   delete options.m_pOCContext;
 #ifdef PDF_ENABLE_XFA
-  options.m_pOCContext = NULL;
+  options.m_pOCContext = nullptr;
 #endif  // PDF_ENABLE_XFA
 }
 
@@ -266,7 +266,7 @@ FPDFDOC_ExitFormFillEnvironment(FPDF_FORMHANDLE hHandle) {
   pApp->RemoveFormFillEnv(pEnv);
 #else   // PDF_ENABLE_XFA
   if (CPDFSDK_Document* pSDKDoc = pEnv->GetSDKDocument()) {
-    pEnv->SetSDKDocument(NULL);
+    pEnv->SetSDKDocument(nullptr);
     delete pSDKDoc;
   }
 #endif  // PDF_ENABLE_XFA
diff --git a/fpdfsdk/fpdfsave.cpp b/fpdfsdk/fpdfsave.cpp
index 9a006530c2..36f553e556 100644
--- a/fpdfsdk/fpdfsave.cpp
+++ b/fpdfsdk/fpdfsave.cpp
@@ -49,7 +49,7 @@ class CFX_IFileWrite final : public IFX_StreamWrite {
 };
 
 CFX_IFileWrite::CFX_IFileWrite() {
-  m_pFileWriteStruct = NULL;
+  m_pFileWriteStruct = nullptr;
 }
 
 FX_BOOL CFX_IFileWrite::Init(FPDF_FILEWRITE* pFileWriteStruct) {
@@ -140,8 +140,8 @@ bool SaveXFADocumentData(CPDFXFA_Document* pDocument,
     ScopedFileStream pTemplate(FX_CreateMemoryStream(pData, dwSize2));
     pContext->UpdateChecksum(pTemplate.get());
   }
-  CPDF_Stream* pFormStream = NULL;
-  CPDF_Stream* pDataSetsStream = NULL;
+  CPDF_Stream* pFormStream = nullptr;
+  CPDF_Stream* pDataSetsStream = nullptr;
   if (iFormIndex != -1) {
     // Get form CPDF_Stream
     CPDF_Object* pFormPDFObj = pArray->GetObjectAt(iFormIndex);
@@ -182,7 +182,7 @@ bool SaveXFADocumentData(CPDFXFA_Document* pDocument,
         if (pDataSetsStream)
           pDataSetsStream->InitStreamFromFile(pDsfileWrite.get(), pDataDict);
       } else {
-        CPDF_Stream* pData = new CPDF_Stream(NULL, 0, NULL);
+        CPDF_Stream* pData = new CPDF_Stream(nullptr, 0, nullptr);
         pData->InitStreamFromFile(pDsfileWrite.get(), pDataDict);
         pPDFDocument->AddIndirectObject(pData);
         iLast = pArray->GetCount() - 2;
@@ -203,7 +203,7 @@ bool SaveXFADocumentData(CPDFXFA_Document* pDocument,
         if (pFormStream)
           pFormStream->InitStreamFromFile(pfileWrite.get(), pDataDict);
       } else {
-        CPDF_Stream* pData = new CPDF_Stream(NULL, 0, NULL);
+        CPDF_Stream* pData = new CPDF_Stream(nullptr, 0, nullptr);
         pData->InitStreamFromFile(pfileWrite.get(), pDataDict);
         pPDFDocument->AddIndirectObject(pData);
         iLast = pArray->GetCount() - 2;
@@ -290,8 +290,7 @@ bool FPDF_Doc_Save(FPDF_DOCUMENT document,
     FileMaker.RemoveSecurity();
   }
 
-  CFX_IFileWrite* pStreamWrite = NULL;
-  pStreamWrite = new CFX_IFileWrite;
+  CFX_IFileWrite* pStreamWrite = new CFX_IFileWrite;
   pStreamWrite->Init(pFileWrite);
   bool bRet = FileMaker.Create(pStreamWrite, flags);
 #ifdef PDF_ENABLE_XFA
diff --git a/fpdfsdk/fpdfview.cpp b/fpdfsdk/fpdfview.cpp
index 24cd8ef5c4..9847f15c60 100644
--- a/fpdfsdk/fpdfview.cpp
+++ b/fpdfsdk/fpdfview.cpp
@@ -335,12 +335,12 @@ DLLEXPORT FPDF_DOCUMENT STDCALL FPDF_LoadDocument(FPDF_STRING file_path,
   if (error != CPDF_Parser::SUCCESS) {
     delete pParser;
     ProcessParseError(error);
-    return NULL;
+    return nullptr;
   }
 #ifdef PDF_ENABLE_XFA
   CPDF_Document* pPDFDoc = pParser->GetDocument();
   if (!pPDFDoc)
-    return NULL;
+    return nullptr;
 
   CPDFXFA_App* pProvider = CPDFXFA_App::GetInstance();
   return new CPDFXFA_Document(pPDFDoc, pProvider);
@@ -419,10 +419,9 @@ DLLEXPORT FPDF_DOCUMENT STDCALL FPDF_LoadMemDocument(const void* data_buf,
   if (error != CPDF_Parser::SUCCESS) {
     delete pParser;
     ProcessParseError(error);
-    return NULL;
+    return nullptr;
   }
-  CPDF_Document* pDoc = NULL;
-  pDoc = pParser ? pParser->GetDocument() : NULL;
+  CPDF_Document* pDoc = pParser ? pParser->GetDocument() : nullptr;
   CheckUnSupportError(pDoc, error);
   return FPDFDocumentFromCPDFDocument(pParser->GetDocument());
 }
@@ -437,10 +436,9 @@ FPDF_LoadCustomDocument(FPDF_FILEACCESS* pFileAccess,
   if (error != CPDF_Parser::SUCCESS) {
     delete pParser;
     ProcessParseError(error);
-    return NULL;
+    return nullptr;
   }
-  CPDF_Document* pDoc = NULL;
-  pDoc = pParser ? pParser->GetDocument() : NULL;
+  CPDF_Document* pDoc = pParser ? pParser->GetDocument() : nullptr;
   CheckUnSupportError(pDoc, error);
   return FPDFDocumentFromCPDFDocument(pParser->GetDocument());
 }
@@ -568,7 +566,7 @@ DLLEXPORT void STDCALL FPDF_RenderPage(HDC dc,
         pDst->Create(size_x, size_y, FXDIB_Rgb32);
         FXSYS_memset(pDst->GetBuffer(), -1, pitch * size_y);
         pDst->CompositeBitmap(0, 0, size_x, size_y, pBitmap, 0, 0,
-                              FXDIB_BLEND_NORMAL, NULL, FALSE, NULL);
+                              FXDIB_BLEND_NORMAL, nullptr, FALSE, nullptr);
         WinDC.StretchDIBits(pDst, 0, 0, size_x, size_y);
         delete pDst;
       } else {
@@ -733,7 +731,7 @@ DLLEXPORT FPDF_BITMAP STDCALL FPDFBitmap_Create(int width,
                                                 int alpha) {
   std::unique_ptr<CFX_DIBitmap> pBitmap(new CFX_DIBitmap);
   if (!pBitmap->Create(width, height, alpha ? FXDIB_Argb : FXDIB_Rgb32)) {
-    return NULL;
+    return nullptr;
   }
   return pBitmap.release();
 }
@@ -758,7 +756,7 @@ DLLEXPORT FPDF_BITMAP STDCALL FPDFBitmap_CreateEx(int width,
       fx_format = FXDIB_Argb;
       break;
     default:
-      return NULL;
+      return nullptr;
   }
   CFX_DIBitmap* pBitmap = new CFX_DIBitmap;
   pBitmap->Create(width, height, fx_format, (uint8_t*)first_scan, stride);
@@ -864,7 +862,7 @@ void FPDF_RenderPage_Retail(CRenderContext* pContext,
     pContext->m_pAnnots = new CPDF_AnnotList(pPage);
     FX_BOOL bPrinting = pContext->m_pDevice->GetDeviceClass() != FXDC_DISPLAY;
     pContext->m_pAnnots->DisplayAnnots(pPage, pContext->m_pContext, bPrinting,
-                                       &matrix, TRUE, NULL);
+                                       &matrix, TRUE, nullptr);
   }
 
   pContext->m_pRenderer = new CPDF_ProgressiveRenderer(
@@ -925,7 +923,7 @@ DLLEXPORT FPDF_PAGERANGE STDCALL
 FPDF_VIEWERREF_GetPrintPageRange(FPDF_DOCUMENT document) {
   CPDF_Document* pDoc = CPDFDocumentFromFPDFDocument(document);
   if (!pDoc)
-    return NULL;
+    return nullptr;
   CPDF_ViewerPreferences viewRef(pDoc);
   return viewRef.PrintPageRange();
 }
@@ -1002,7 +1000,7 @@ DLLEXPORT FPDF_RESULT STDCALL FPDF_BStr_Set(FPDF_BSTR* str,
   if (length == 0) {
     if (str->str) {
       FX_Free(str->str);
-      str->str = NULL;
+      str->str = nullptr;
     }
     str->len = 0;
     return 0;
@@ -1014,9 +1012,6 @@ DLLEXPORT FPDF_RESULT STDCALL FPDF_BStr_Set(FPDF_BSTR* str,
     str->str = FX_Alloc(char, length + 1);
 
   str->str[length] = 0;
-  if (str->str == NULL)
-    return -1;
-
   FXSYS_memcpy(str->str, bstr, length);
   str->len = length;
 
@@ -1029,7 +1024,7 @@ DLLEXPORT FPDF_RESULT STDCALL FPDF_BStr_Clear(FPDF_BSTR* str) {
 
   if (str->str) {
     FX_Free(str->str);
-    str->str = NULL;
+    str->str = nullptr;
   }
   str->len = 0;
   return 0;
diff --git a/fpdfsdk/fpdfview_embeddertest.cpp b/fpdfsdk/fpdfview_embeddertest.cpp
index 80b39b5b9c..820d496bdc 100644
--- a/fpdfsdk/fpdfview_embeddertest.cpp
+++ b/fpdfsdk/fpdfview_embeddertest.cpp
@@ -180,11 +180,11 @@ TEST_F(FPDFViewEmbeddertest, NamedDests) {
 TEST_F(FPDFViewEmbeddertest, NamedDestsByName) {
   EXPECT_TRUE(OpenDocument("named_dests.pdf"));
 
-  // Null pointer returns NULL.
+  // Null pointer returns nullptr.
   FPDF_DEST dest = FPDF_GetNamedDestByName(document(), nullptr);
   EXPECT_EQ(nullptr, dest);
 
-  // Empty string returns NULL.
+  // Empty string returns nullptr.
   dest = FPDF_GetNamedDestByName(document(), "");
   EXPECT_EQ(nullptr, dest);
 
diff --git a/fpdfsdk/fpdfxfa/fpdfxfa_app.cpp b/fpdfsdk/fpdfxfa/fpdfxfa_app.cpp
index fc15c3b1b3..ffc4e5363a 100644
--- a/fpdfsdk/fpdfxfa/fpdfxfa_app.cpp
+++ b/fpdfsdk/fpdfxfa/fpdfxfa_app.cpp
@@ -14,7 +14,7 @@
 #include "xfa/fxfa/include/xfa_ffapp.h"
 #include "xfa/fxfa/include/xfa_fontmgr.h"
 
-CPDFXFA_App* CPDFXFA_App::g_pApp = NULL;
+CPDFXFA_App* CPDFXFA_App::g_pApp = nullptr;
 
 CPDFXFA_App* CPDFXFA_App::GetInstance() {
   if (!g_pApp) {
@@ -25,12 +25,12 @@ CPDFXFA_App* CPDFXFA_App::GetInstance() {
 
 void CPDFXFA_App::ReleaseInstance() {
   delete g_pApp;
-  g_pApp = NULL;
+  g_pApp = nullptr;
 }
 
 CPDFXFA_App::CPDFXFA_App()
     : m_bJavaScriptInitialized(FALSE),
-      m_pXFAApp(NULL),
+      m_pXFAApp(nullptr),
       m_pIsolate(nullptr),
       m_csAppType(JS_STR_VIEWERTYPE_STANDARD) {
   m_pEnvList.RemoveAll();
@@ -38,7 +38,7 @@ CPDFXFA_App::CPDFXFA_App()
 
 CPDFXFA_App::~CPDFXFA_App() {
   delete m_pXFAApp;
-  m_pXFAApp = NULL;
+  m_pXFAApp = nullptr;
 
   FXJSE_Runtime_Release(m_pIsolate);
   m_pIsolate = nullptr;
@@ -190,8 +190,8 @@ CFX_WideString CPDFXFA_App::Response(const CFX_WideString& wsQuestion,
     int nLength = 2048;
     char* pBuff = new char[nLength];
     nLength = pEnv->JS_appResponse(wsQuestion.c_str(), wsTitle.c_str(),
-                                   wsDefaultAnswer.c_str(), NULL, bMark, pBuff,
-                                   nLength);
+                                   wsDefaultAnswer.c_str(), nullptr, bMark,
+                                   pBuff, nLength);
     if (nLength > 0) {
       nLength = nLength > 2046 ? 2046 : nLength;
       pBuff[nLength] = 0;
@@ -350,7 +350,7 @@ void CPDFXFA_App::LoadString(int32_t iStringID, CFX_WideString& wsString) {
 }
 
 IFWL_AdapterTimerMgr* CPDFXFA_App::GetTimerMgr() {
-  CXFA_FWLAdapterTimerMgr* pAdapter = NULL;
+  CXFA_FWLAdapterTimerMgr* pAdapter = nullptr;
   CPDFDoc_Environment* pEnv = m_pEnvList.GetAt(0);
   if (pEnv)
     pAdapter = new CXFA_FWLAdapterTimerMgr(pEnv);
diff --git a/fpdfsdk/fpdfxfa/fpdfxfa_doc.cpp b/fpdfsdk/fpdfxfa/fpdfxfa_doc.cpp
index f207760398..9d8fb42059 100644
--- a/fpdfsdk/fpdfxfa/fpdfxfa_doc.cpp
+++ b/fpdfsdk/fpdfxfa/fpdfxfa_doc.cpp
@@ -127,7 +127,7 @@ FX_BOOL CPDFXFA_Document::LoadXFADoc() {
     return FALSE;
   }
 
-  m_pXFADocView->DoLayout(NULL);
+  m_pXFADocView->DoLayout(nullptr);
   m_pXFADocView->StopLayout();
   m_nLoadStatus = FXFA_LOADSTATUS_LOADED;
 
@@ -214,7 +214,7 @@ void CPDFXFA_Document::DeletePage(int page_index) {
 }
 
 void CPDFXFA_Document::RemovePage(CPDFXFA_Page* page) {
-  m_XFAPageList.SetAt(page->GetPageIndex(), NULL);
+  m_XFAPageList.SetAt(page->GetPageIndex(), nullptr);
 }
 
 CPDFSDK_Document* CPDFXFA_Document::GetSDKDocument(
@@ -257,8 +257,7 @@ void CPDFXFA_Document::InvalidateRect(CXFA_FFPageView* pPageView,
   FXRect2PDFRect(rt, rcPage);
 
   CPDFXFA_Page* pPage = GetPage(pPageView);
-
-  if (pPage == NULL)
+  if (!pPage)
     return;
 
   CPDFDoc_Environment* pEnv = m_pSDKDoc->GetEnv();
@@ -296,10 +295,7 @@ void CPDFXFA_Document::InvalidateRect(CXFA_FFWidget* hWidget,
 void CPDFXFA_Document::DisplayCaret(CXFA_FFWidget* hWidget,
                                     FX_BOOL bVisible,
                                     const CFX_RectF* pRtAnchor) {
-  if (!hWidget || pRtAnchor == NULL)
-    return;
-
-  if (!m_pXFADoc || !m_pSDKDoc || !m_pXFADocView)
+  if (!hWidget || !pRtAnchor || !m_pXFADoc || !m_pSDKDoc || !m_pXFADocView)
     return;
 
   if (m_iDocType != DOCTYPE_DYNAMIC_XFA)
@@ -314,8 +310,7 @@ void CPDFXFA_Document::DisplayCaret(CXFA_FFWidget* hWidget,
     return;
 
   CPDFXFA_Page* pPage = GetPage(pPageView);
-
-  if (pPage == NULL)
+  if (!pPage)
     return;
 
   CFX_FloatRect rcCaret;
@@ -485,7 +480,8 @@ FX_BOOL CPDFXFA_Document::PopupMenu(CXFA_FFWidget* hWidget,
     menuFlag |= FXFA_MEMU_SELECTALL;
 
   CPDFDoc_Environment* pEnv = m_pSDKDoc->GetEnv();
-  return pEnv && pEnv->FFI_PopupMenu(pPage, hWidget, menuFlag, ptPopup, NULL);
+  return pEnv &&
+         pEnv->FFI_PopupMenu(pPage, hWidget, menuFlag, ptPopup, nullptr);
 }
 
 void CPDFXFA_Document::PageViewEvent(CXFA_FFPageView* pPageView,
@@ -602,13 +598,11 @@ void CPDFXFA_Document::SetCalculationsEnabled(CXFA_FFDoc* hDoc,
 }
 
 void CPDFXFA_Document::GetTitle(CXFA_FFDoc* hDoc, CFX_WideString& wsTitle) {
-  if (hDoc != m_pXFADoc)
-    return;
-  if (m_pPDFDoc == NULL)
+  if (hDoc != m_pXFADoc || !m_pPDFDoc)
     return;
-  CPDF_Dictionary* pInfoDict = m_pPDFDoc->GetInfo();
 
-  if (pInfoDict == NULL)
+  CPDF_Dictionary* pInfoDict = m_pPDFDoc->GetInfo();
+  if (!pInfoDict)
     return;
 
   CFX_ByteString csTitle = pInfoDict->GetStringBy("Title");
@@ -731,7 +725,7 @@ void CPDFXFA_Document::GotoURL(CXFA_FFDoc* hDoc,
     return;
 
   CPDFDoc_Environment* pEnv = m_pSDKDoc->GetEnv();
-  if (pEnv == NULL)
+  if (!pEnv)
     return;
 
   CFX_WideStringC str(bsURL.c_str());
@@ -759,15 +753,15 @@ void CPDFXFA_Document::SetFocusWidget(CXFA_FFDoc* hDoc,
   if (hDoc != m_pXFADoc)
     return;
 
-  if (NULL == hWidget) {
-    m_pSDKDoc->SetFocusAnnot(NULL);
+  if (!hWidget) {
+    m_pSDKDoc->SetFocusAnnot(nullptr);
     return;
   }
 
   int pageViewCount = m_pSDKDoc->GetPageViewCount();
   for (int i = 0; i < pageViewCount; i++) {
     CPDFSDK_PageView* pPageView = m_pSDKDoc->GetPageView(i);
-    if (pPageView == NULL)
+    if (!pPageView)
       continue;
     CPDFSDK_Annot* pAnnot = pPageView->GetAnnotByXFAWidget(hWidget);
     if (pAnnot) {
@@ -784,14 +778,12 @@ void CPDFXFA_Document::Print(CXFA_FFDoc* hDoc,
     return;
 
   CPDFDoc_Environment* pEnv = m_pSDKDoc->GetEnv();
-  if (pEnv == NULL)
+  if (!pEnv || !pEnv->GetFormFillInfo() ||
+      !pEnv->GetFormFillInfo()->m_pJsPlatform ||
+      !pEnv->GetFormFillInfo()->m_pJsPlatform->Doc_print) {
     return;
+  }
 
-  if (!pEnv->GetFormFillInfo() ||
-      pEnv->GetFormFillInfo()->m_pJsPlatform == NULL)
-    return;
-  if (pEnv->GetFormFillInfo()->m_pJsPlatform->Doc_print == NULL)
-    return;
   pEnv->GetFormFillInfo()->m_pJsPlatform->Doc_print(
       pEnv->GetFormFillInfo()->m_pJsPlatform,
       dwOptions & XFA_PRINTOPT_ShowDialog, nStartPage, nEndPage,
@@ -805,7 +797,7 @@ void CPDFXFA_Document::GetURL(CXFA_FFDoc* hDoc, CFX_WideString& wsDocURL) {
     return;
 
   CPDFDoc_Environment* pEnv = m_pSDKDoc->GetEnv();
-  if (pEnv == NULL)
+  if (!pEnv)
     return;
 
   pEnv->FFI_GetURL(this, wsDocURL);
@@ -907,9 +899,7 @@ void CPDFXFA_Document::_OnAfterNotifySumbit() {
 }
 
 FX_BOOL CPDFXFA_Document::SubmitData(CXFA_FFDoc* hDoc, CXFA_Submit submit) {
-  if (!_NotifySubmit(TRUE))
-    return FALSE;
-  if (NULL == m_pXFADocView)
+  if (!_NotifySubmit(TRUE) || !m_pXFADocView)
     return FALSE;
   m_pXFADocView->UpdateDocView();
 
@@ -921,7 +911,7 @@ FX_BOOL CPDFXFA_Document::SubmitData(CXFA_FFDoc* hDoc, CXFA_Submit submit) {
 IFX_FileRead* CPDFXFA_Document::OpenLinkedFile(CXFA_FFDoc* hDoc,
                                                const CFX_WideString& wsLink) {
   CPDFDoc_Environment* pEnv = m_pSDKDoc->GetEnv();
-  if (pEnv == NULL)
+  if (!pEnv)
     return FALSE;
   CFX_ByteString bs = wsLink.UTF16LE_Encode();
   int len = bs.GetLength() / sizeof(unsigned short);
@@ -929,8 +919,8 @@ IFX_FileRead* CPDFXFA_Document::OpenLinkedFile(CXFA_FFDoc* hDoc,
       0, (FPDF_WIDESTRING)bs.GetBuffer(len * sizeof(unsigned short)), "rb");
   bs.ReleaseBuffer(len * sizeof(unsigned short));
 
-  if (pFileHandler == NULL)
-    return NULL;
+  if (!pFileHandler)
+    return nullptr;
   return new CFPDF_FileStream(pFileHandler);
 }
 FX_BOOL CPDFXFA_Document::_ExportSubmitFile(FPDF_FILEHANDLER* pFileHandler,
diff --git a/fpdfsdk/fpdfxfa/include/fpdfxfa_doc.h b/fpdfsdk/fpdfxfa/include/fpdfxfa_doc.h
index 9cab4d941b..90ef6f36b3 100644
--- a/fpdfsdk/fpdfxfa/include/fpdfxfa_doc.h
+++ b/fpdfsdk/fpdfxfa/include/fpdfxfa_doc.h
@@ -66,7 +66,7 @@ class CPDFXFA_Document : public IXFA_DocProvider {
                               CFX_RectF& rtPopup);
   virtual FX_BOOL PopupMenu(CXFA_FFWidget* hWidget,
                             CFX_PointF ptPopup,
-                            const CFX_RectF* pRectExclude = NULL);
+                            const CFX_RectF* pRectExclude = nullptr);
 
   // dwFlags XFA_PAGEVIEWEVENT_Added, XFA_PAGEVIEWEVENT_Removing
   virtual void PageViewEvent(CXFA_FFPageView* pPageView, uint32_t dwFlags);
@@ -177,7 +177,7 @@ class CPDFXFA_Document : public IXFA_DocProvider {
   virtual CPDF_Document* OpenPDF(CXFA_FFDoc* hDoc,
                                  IFX_FileRead* pFile,
                                  FX_BOOL bTakeOverFile) {
-    return NULL;
+    return nullptr;
   }
 
   virtual IFX_FileRead* OpenLinkedFile(CXFA_FFDoc* hDoc,
diff --git a/fpdfsdk/fsdk_actionhandler.cpp b/fpdfsdk/fsdk_actionhandler.cpp
index 912bc40c7f..bc6bd2826c 100644
--- a/fpdfsdk/fsdk_actionhandler.cpp
+++ b/fpdfsdk/fsdk_actionhandler.cpp
@@ -223,7 +223,7 @@ FX_BOOL CPDFSDK_ActionHandler::IsValidField(CPDFSDK_Document* pDocument,
 
   CPDFSDK_InterForm* pInterForm = pDocument->GetInterForm();
   CPDF_InterForm* pPDFInterForm = pInterForm->GetInterForm();
-  return pPDFInterForm->GetFieldByDict(pFieldDict) != NULL;
+  return !!pPDFInterForm->GetFieldByDict(pFieldDict);
 }
 
 FX_BOOL CPDFSDK_ActionHandler::ExecuteFieldAction(
diff --git a/fpdfsdk/fsdk_annothandler.cpp b/fpdfsdk/fsdk_annothandler.cpp
index cbcb53e169..eda3b49058 100644
--- a/fpdfsdk/fsdk_annothandler.cpp
+++ b/fpdfsdk/fsdk_annothandler.cpp
@@ -88,7 +88,7 @@ CPDFSDK_Annot* CPDFSDK_AnnotHandlerMgr::NewAnnot(CXFA_FFWidget* pAnnot,
     return pAnnotHandler->NewAnnot(pAnnot, pPageView);
   }
 
-  return NULL;
+  return nullptr;
 }
 #endif  // PDF_ENABLE_XFA
 
@@ -367,8 +367,8 @@ CPDFSDK_Annot* CPDFSDK_AnnotHandlerMgr::GetNextAnnot(CPDFSDK_Annot* pSDKAnnot,
 #ifdef PDF_ENABLE_XFA
   CPDFSDK_PageView* pPageView = pSDKAnnot->GetPageView();
   CPDFXFA_Page* pPage = pPageView->GetPDFXFAPage();
-  if (pPage == NULL)
-    return NULL;
+  if (!pPage)
+    return nullptr;
   if (pPage->GetPDFPage()) {  // for pdf annots.
     CBA_AnnotIterator ai(pSDKAnnot->GetPageView(), pSDKAnnot->GetType(), "");
     CPDFSDK_Annot* pNext =
@@ -441,7 +441,7 @@ CPDFSDK_Annot* CPDFSDK_BFAnnotHandler::NewAnnot(CPDF_Annot* pAnnot,
 #ifdef PDF_ENABLE_XFA
 CPDFSDK_Annot* CPDFSDK_BFAnnotHandler::NewAnnot(CXFA_FFWidget* hWidget,
                                                 CPDFSDK_PageView* pPage) {
-  return NULL;
+  return nullptr;
 }
 #endif  // PDF_ENABLE_XFA
 
@@ -653,7 +653,7 @@ void CPDFSDK_BFAnnotHandler::OnLoad(CPDFSDK_Annot* pAnnot) {
 
   CPDFSDK_Widget* pWidget = (CPDFSDK_Widget*)pAnnot;
   if (!pWidget->IsAppearanceValid())
-    pWidget->ResetAppearance(NULL, FALSE);
+    pWidget->ResetAppearance(nullptr, FALSE);
 
   int nFieldType = pWidget->GetFieldType();
   if (nFieldType == FIELDTYPE_TEXTFIELD || nFieldType == FIELDTYPE_COMBOBOX) {
@@ -736,7 +736,7 @@ CPDFSDK_Annot* CPDFSDK_XFAAnnotHandler::NewAnnot(CXFA_FFWidget* pAnnot,
 }
 
 FX_BOOL CPDFSDK_XFAAnnotHandler::CanAnswer(CPDFSDK_Annot* pAnnot) {
-  return pAnnot->GetXFAWidget() != NULL;
+  return !!pAnnot->GetXFAWidget();
 }
 
 void CPDFSDK_XFAAnnotHandler::OnDraw(CPDFSDK_PageView* pPageView,
@@ -744,8 +744,8 @@ void CPDFSDK_XFAAnnotHandler::OnDraw(CPDFSDK_PageView* pPageView,
                                      CFX_RenderDevice* pDevice,
                                      CFX_Matrix* pUser2Device,
                                      uint32_t dwFlags) {
-  ASSERT(pPageView != NULL);
-  ASSERT(pAnnot != NULL);
+  ASSERT(pPageView);
+  ASSERT(pAnnot);
 
   CPDFSDK_Document* pSDKDoc = pPageView->GetSDKDocument();
   CXFA_FFWidgetHandler* pWidgetHandler = GetXFAWidgetHandler(pAnnot);
@@ -982,7 +982,7 @@ FX_BOOL CPDFSDK_XFAAnnotHandler::OnKillFocus(CPDFSDK_Annot* pAnnot,
 
 FX_BOOL CPDFSDK_XFAAnnotHandler::OnXFAChangedFocus(CPDFSDK_Annot* pOldAnnot,
                                                    CPDFSDK_Annot* pNewAnnot) {
-  CXFA_FFWidgetHandler* pWidgetHandler = NULL;
+  CXFA_FFWidgetHandler* pWidgetHandler = nullptr;
 
   if (pOldAnnot)
     pWidgetHandler = GetXFAWidgetHandler(pOldAnnot);
@@ -991,7 +991,7 @@ FX_BOOL CPDFSDK_XFAAnnotHandler::OnXFAChangedFocus(CPDFSDK_Annot* pOldAnnot,
 
   if (pWidgetHandler) {
     FX_BOOL bRet = TRUE;
-    CXFA_FFWidget* hWidget = pNewAnnot ? pNewAnnot->GetXFAWidget() : NULL;
+    CXFA_FFWidget* hWidget = pNewAnnot ? pNewAnnot->GetXFAWidget() : nullptr;
     if (hWidget) {
       CXFA_FFPageView* pXFAPageView = hWidget->GetPageView();
       if (pXFAPageView) {
@@ -1009,23 +1009,23 @@ FX_BOOL CPDFSDK_XFAAnnotHandler::OnXFAChangedFocus(CPDFSDK_Annot* pOldAnnot,
 CXFA_FFWidgetHandler* CPDFSDK_XFAAnnotHandler::GetXFAWidgetHandler(
     CPDFSDK_Annot* pAnnot) {
   if (!pAnnot)
-    return NULL;
+    return nullptr;
 
   CPDFSDK_PageView* pPageView = pAnnot->GetPageView();
   if (!pPageView)
-    return NULL;
+    return nullptr;
 
   CPDFSDK_Document* pSDKDoc = pPageView->GetSDKDocument();
   if (!pSDKDoc)
-    return NULL;
+    return nullptr;
 
   CPDFXFA_Document* pDoc = pSDKDoc->GetXFADocument();
   if (!pDoc)
-    return NULL;
+    return nullptr;
 
   CXFA_FFDocView* pDocView = pDoc->GetXFADocView();
   if (!pDocView)
-    return NULL;
+    return nullptr;
 
   return pDocView->GetWidgetHandler();
 }
diff --git a/fpdfsdk/fsdk_baseannot.cpp b/fpdfsdk/fsdk_baseannot.cpp
index 7dcb663505..b628ae684f 100644
--- a/fpdfsdk/fsdk_baseannot.cpp
+++ b/fpdfsdk/fsdk_baseannot.cpp
@@ -554,7 +554,7 @@ void CPDFSDK_BAAnnot::DrawAppearance(CFX_RenderDevice* pDevice,
 }
 
 FX_BOOL CPDFSDK_BAAnnot::IsAppearanceValid() {
-  return m_pAnnot->GetAnnotDict()->GetDictBy("AP") != NULL;
+  return !!m_pAnnot->GetAnnotDict()->GetDictBy("AP");
 }
 
 FX_BOOL CPDFSDK_BAAnnot::IsAppearanceValid(CPDF_Annot::AppearanceMode mode) {
@@ -914,7 +914,7 @@ void CPDFSDK_BAAnnot::Annot_OnDraw(CFX_RenderDevice* pDevice,
                                    CPDF_RenderOptions* pOptions) {
   m_pAnnot->GetAPForm(m_pPageView->GetPDFPage(), CPDF_Annot::Normal);
   m_pAnnot->DrawAppearance(m_pPageView->GetPDFPage(), pDevice, pUser2Device,
-                           CPDF_Annot::Normal, NULL);
+                           CPDF_Annot::Normal, nullptr);
 }
 
 UnderlyingPageType* CPDFSDK_Annot::GetUnderlyingPage() {
diff --git a/fpdfsdk/fsdk_baseform.cpp b/fpdfsdk/fsdk_baseform.cpp
index 0f1a0ad0d1..65be7c8c5d 100644
--- a/fpdfsdk/fsdk_baseform.cpp
+++ b/fpdfsdk/fsdk_baseform.cpp
@@ -41,8 +41,8 @@ CPDFSDK_Widget::CPDFSDK_Widget(CPDF_Annot* pAnnot,
       m_nValueAge(0)
 #ifdef PDF_ENABLE_XFA
       ,
-      m_hMixXFAWidget(NULL),
-      m_pWidgetHandler(NULL)
+      m_hMixXFAWidget(nullptr),
+      m_pWidgetHandler(nullptr)
 #endif  // PDF_ENABLE_XFA
 {
 }
@@ -72,7 +72,7 @@ CXFA_FFWidget* CPDFSDK_Widget::GetMixXFAWidget() const {
     return m_hMixXFAWidget;
   }
 
-  return NULL;
+  return nullptr;
 }
 
 CXFA_FFWidget* CPDFSDK_Widget::GetGroupMixXFAWidget() {
@@ -101,7 +101,7 @@ CXFA_FFWidgetHandler* CPDFSDK_Widget::GetXFAWidgetHandler() const {
     return m_pWidgetHandler;
   }
 
-  return NULL;
+  return nullptr;
 }
 
 static XFA_EVENTTYPE GetXFAEventType(PDFSDK_XFAAActionType eXFAAAT) {
@@ -774,7 +774,7 @@ CFX_WideString CPDFSDK_Widget::OnFormat(FX_BOOL& bFormated) {
 void CPDFSDK_Widget::ResetFieldAppearance(FX_BOOL bValueChanged) {
   CPDF_FormField* pFormField = GetFormField();
   ASSERT(pFormField);
-  m_pInterForm->ResetFieldAppearance(pFormField, NULL, bValueChanged);
+  m_pInterForm->ResetFieldAppearance(pFormField, nullptr, bValueChanged);
 }
 
 void CPDFSDK_Widget::DrawAppearance(CFX_RenderDevice* pDevice,
@@ -932,9 +932,9 @@ void CPDFSDK_Widget::ResetAppearance_PushButton() {
     csDownCaption = pControl->GetDownCaption();
   }
 
-  CPDF_Stream* pNormalIcon = NULL;
-  CPDF_Stream* pRolloverIcon = NULL;
-  CPDF_Stream* pDownIcon = NULL;
+  CPDF_Stream* pNormalIcon = nullptr;
+  CPDF_Stream* pRolloverIcon = nullptr;
+  CPDF_Stream* pDownIcon = nullptr;
 
   if (pControl->HasMKEntry("I")) {
     pNormalIcon = pControl->GetNormalIcon();
@@ -1571,7 +1571,7 @@ void CPDFSDK_Widget::ResetAppearance_TextField(const FX_WCHAR* sValue) {
   CFX_FloatRect rcContent = pEdit->GetContentRect();
 
   CFX_ByteString sEdit = CPWL_Utils::GetEditAppStream(
-      pEdit, CFX_FloatPoint(0.0f, 0.0f), NULL, !bCharArray, subWord);
+      pEdit, CFX_FloatPoint(0.0f, 0.0f), nullptr, !bCharArray, subWord);
 
   if (sEdit.GetLength() > 0) {
     sBody << "/Tx BMC\n"
@@ -2487,10 +2487,8 @@ FX_BOOL CPDFSDK_InterForm::SubmitForm(const CFX_WideString& sDestination,
 
   pEnv->JS_docSubmitForm(pBuffer, nBufSize, sDestination.c_str());
 
-  if (bUrlEncoded) {
+  if (bUrlEncoded)
     FX_Free(pBuffer);
-    pBuffer = NULL;
-  }
 
   return TRUE;
 }
@@ -2586,7 +2584,7 @@ int CPDFSDK_InterForm::BeforeSelectionChange(CPDF_FormField* pField,
 void CPDFSDK_InterForm::AfterSelectionChange(CPDF_FormField* pField) {
   if (pField->GetFieldType() == FIELDTYPE_LISTBOX) {
     OnCalculate(pField);
-    ResetFieldAppearance(pField, NULL, TRUE);
+    ResetFieldAppearance(pField, nullptr, TRUE);
     UpdateField(pField);
   }
 }
diff --git a/fpdfsdk/fsdk_mgr.cpp b/fpdfsdk/fsdk_mgr.cpp
index 83fee907d2..835439394d 100644
--- a/fpdfsdk/fsdk_mgr.cpp
+++ b/fpdfsdk/fsdk_mgr.cpp
@@ -41,7 +41,7 @@ FPDF_WIDESTRING AsFPDFWideString(CFX_ByteString* bsUTF16LE) {
 
 CPDFDoc_Environment::CPDFDoc_Environment(UnderlyingDocumentType* pDoc,
                                          FPDF_FORMFILLINFO* pFFinfo)
-    : m_pInfo(pFFinfo), m_pSDKDoc(NULL), m_pUnderlyingDoc(pDoc) {
+    : m_pInfo(pFFinfo), m_pSDKDoc(nullptr), m_pUnderlyingDoc(pDoc) {
   m_pSysHandler.reset(new CFX_SystemHandler(this));
 }
 
@@ -202,7 +202,7 @@ void CPDFDoc_Environment::JS_docgotoPage(int nPageNum) {
 
 IJS_Runtime* CPDFDoc_Environment::GetJSRuntime() {
   if (!IsJSInitiated())
-    return NULL;
+    return nullptr;
   if (!m_pJSRuntime)
     m_pJSRuntime.reset(IJS_Runtime::Create(this));
   return m_pJSRuntime.get();
@@ -427,7 +427,7 @@ FX_BOOL CPDFSDK_Document::KillFocusAnnot(FX_UINT nFlag) {
         int nFieldType = pWidget->GetFieldType();
         if (FIELDTYPE_TEXTFIELD == nFieldType ||
             FIELDTYPE_COMBOBOX == nFieldType) {
-          m_pEnv->FFI_OnSetFieldInputFocus(NULL, NULL, 0, FALSE);
+          m_pEnv->FFI_OnSetFieldInputFocus(nullptr, nullptr, 0, FALSE);
         }
       }
 
@@ -667,7 +667,7 @@ CPDFSDK_Annot* CPDFSDK_PageView::AddAnnot(CPDF_Dictionary* pDict) {
 
 CPDFSDK_Annot* CPDFSDK_PageView::AddAnnot(const FX_CHAR* lpSubType,
                                           CPDF_Dictionary* pDict) {
-  return NULL;
+  return nullptr;
 }
 
 FX_BOOL CPDFSDK_PageView::DeleteAnnot(CPDFSDK_Annot* pAnnot) {
@@ -706,7 +706,7 @@ CPDF_Document* CPDFSDK_PageView::GetPDFDocument() {
     return m_page->m_pDocument;
 #endif  // PDF_ENABLE_XFA
   }
-  return NULL;
+  return nullptr;
 }
 
 #ifdef PDF_ENABLE_XFA
@@ -714,7 +714,7 @@ CPDF_Page* CPDFSDK_PageView::GetPDFPage() {
   if (m_page) {
     return m_page->GetPDFPage();
   }
-  return NULL;
+  return nullptr;
 }
 #endif  // PDF_ENABLE_XFA
 
@@ -775,7 +775,7 @@ FX_BOOL CPDFSDK_PageView::OnRButtonDown(const CFX_FloatPoint& point,
 
   CPDFSDK_Annot* pFXAnnot = GetFXWidgetAtPoint(point.x, point.y);
 
-  if (pFXAnnot == NULL)
+  if (!pFXAnnot)
     return FALSE;
 
   FX_BOOL bRet =
@@ -794,7 +794,7 @@ FX_BOOL CPDFSDK_PageView::OnRButtonUp(const CFX_FloatPoint& point,
 
   CPDFSDK_Annot* pFXAnnot = GetFXWidgetAtPoint(point.x, point.y);
 
-  if (pFXAnnot == NULL)
+  if (!pFXAnnot)
     return FALSE;
 
   FX_BOOL bRet =
@@ -848,7 +848,7 @@ FX_BOOL CPDFSDK_PageView::OnMouseMove(const CFX_FloatPoint& point, int nFlag) {
     m_bEnterWidget = FALSE;
     if (m_CaptureWidget) {
       pAnnotHandlerMgr->Annot_OnMouseExit(this, m_CaptureWidget, nFlag);
-      m_CaptureWidget = NULL;
+      m_CaptureWidget = nullptr;
     }
   }
   return FALSE;
diff --git a/fpdfsdk/fsdk_rendercontext.cpp b/fpdfsdk/fsdk_rendercontext.cpp
index 3ba60778a7..0888d6ba4a 100644
--- a/fpdfsdk/fsdk_rendercontext.cpp
+++ b/fpdfsdk/fsdk_rendercontext.cpp
@@ -10,11 +10,11 @@
 #include "core/fxge/include/fx_ge.h"
 
 void CRenderContext::Clear() {
-  m_pDevice = NULL;
-  m_pContext = NULL;
-  m_pRenderer = NULL;
-  m_pAnnots = NULL;
-  m_pOptions = NULL;
+  m_pDevice = nullptr;
+  m_pContext = nullptr;
+  m_pRenderer = nullptr;
+  m_pAnnots = nullptr;
+  m_pOptions = nullptr;
 }
 
 CRenderContext::~CRenderContext() {
diff --git a/fpdfsdk/fxedit/fxet_ap.cpp b/fpdfsdk/fxedit/fxet_ap.cpp
index 563acb65b5..5420b46218 100644
--- a/fpdfsdk/fxedit/fxet_ap.cpp
+++ b/fpdfsdk/fxedit/fxet_ap.cpp
@@ -56,12 +56,11 @@ static CFX_ByteString GetFontSetString(IPVT_FontMap* pFontMap,
   return sRet.MakeString();
 }
 
-CFX_ByteString IFX_Edit::GetEditAppearanceStream(
-    IFX_Edit* pEdit,
-    const CFX_FloatPoint& ptOffset,
-    const CPVT_WordRange* pRange /* = NULL*/,
-    FX_BOOL bContinuous /* = TRUE*/,
-    uint16_t SubWord /* = 0*/) {
+CFX_ByteString IFX_Edit::GetEditAppearanceStream(IFX_Edit* pEdit,
+                                                 const CFX_FloatPoint& ptOffset,
+                                                 const CPVT_WordRange* pRange,
+                                                 FX_BOOL bContinuous,
+                                                 uint16_t SubWord) {
   CFX_ByteTextBuf sEditStream, sWords;
 
   CFX_FloatPoint ptOld(0.0f, 0.0f), ptNew(0.0f, 0.0f);
diff --git a/fpdfsdk/fxedit/fxet_edit.cpp b/fpdfsdk/fxedit/fxet_edit.cpp
index 0124913c5f..589ac1bd41 100644
--- a/fpdfsdk/fxedit/fxet_edit.cpp
+++ b/fpdfsdk/fxedit/fxet_edit.cpp
@@ -339,7 +339,7 @@ IFX_Edit_UndoItem* CFX_Edit_Undo::GetItem(int32_t nIndex) {
   if (nIndex >= 0 && nIndex < m_UndoItemStack.GetSize())
     return m_UndoItemStack.GetAt(nIndex);
 
-  return NULL;
+  return nullptr;
 }
 
 void CFX_Edit_Undo::RemoveHeads() {
@@ -576,8 +576,8 @@ void CFXEU_Clear::Undo() {
   if (m_pEdit) {
     m_pEdit->SelectNone();
     m_pEdit->SetCaret(m_wrSel.BeginPos);
-    m_pEdit->InsertText(m_swText.c_str(), DEFAULT_CHARSET, NULL, NULL, FALSE,
-                        TRUE);
+    m_pEdit->InsertText(m_swText.c_str(), DEFAULT_CHARSET, nullptr, nullptr,
+                        FALSE, TRUE);
     m_pEdit->SetSel(m_wrSel.BeginPos, m_wrSel.EndPos);
   }
 }
@@ -1079,83 +1079,83 @@ void CFX_Edit::SetRichText(FX_BOOL bRichText, FX_BOOL bPaint) {
 FX_BOOL CFX_Edit::SetRichFontIndex(int32_t nFontIndex) {
   CPVT_WordProps WordProps;
   WordProps.nFontIndex = nFontIndex;
-  return SetRichTextProps(EP_FONTINDEX, NULL, &WordProps);
+  return SetRichTextProps(EP_FONTINDEX, nullptr, &WordProps);
 }
 
 FX_BOOL CFX_Edit::SetRichFontSize(FX_FLOAT fFontSize) {
   CPVT_WordProps WordProps;
   WordProps.fFontSize = fFontSize;
-  return SetRichTextProps(EP_FONTSIZE, NULL, &WordProps);
+  return SetRichTextProps(EP_FONTSIZE, nullptr, &WordProps);
 }
 
 FX_BOOL CFX_Edit::SetRichTextColor(FX_COLORREF dwColor) {
   CPVT_WordProps WordProps;
   WordProps.dwWordColor = dwColor;
-  return SetRichTextProps(EP_WORDCOLOR, NULL, &WordProps);
+  return SetRichTextProps(EP_WORDCOLOR, nullptr, &WordProps);
 }
 
 FX_BOOL CFX_Edit::SetRichTextScript(CPDF_VariableText::ScriptType nScriptType) {
   CPVT_WordProps WordProps;
   WordProps.nScriptType = nScriptType;
-  return SetRichTextProps(EP_SCRIPTTYPE, NULL, &WordProps);
+  return SetRichTextProps(EP_SCRIPTTYPE, nullptr, &WordProps);
 }
 
 FX_BOOL CFX_Edit::SetRichTextBold(FX_BOOL bBold) {
   CPVT_WordProps WordProps;
   if (bBold)
     WordProps.nWordStyle |= PVTWORD_STYLE_BOLD;
-  return SetRichTextProps(EP_BOLD, NULL, &WordProps);
+  return SetRichTextProps(EP_BOLD, nullptr, &WordProps);
 }
 
 FX_BOOL CFX_Edit::SetRichTextItalic(FX_BOOL bItalic) {
   CPVT_WordProps WordProps;
   if (bItalic)
     WordProps.nWordStyle |= PVTWORD_STYLE_ITALIC;
-  return SetRichTextProps(EP_ITALIC, NULL, &WordProps);
+  return SetRichTextProps(EP_ITALIC, nullptr, &WordProps);
 }
 
 FX_BOOL CFX_Edit::SetRichTextUnderline(FX_BOOL bUnderline) {
   CPVT_WordProps WordProps;
   if (bUnderline)
     WordProps.nWordStyle |= PVTWORD_STYLE_UNDERLINE;
-  return SetRichTextProps(EP_UNDERLINE, NULL, &WordProps);
+  return SetRichTextProps(EP_UNDERLINE, nullptr, &WordProps);
 }
 
 FX_BOOL CFX_Edit::SetRichTextCrossout(FX_BOOL bCrossout) {
   CPVT_WordProps WordProps;
   if (bCrossout)
     WordProps.nWordStyle |= PVTWORD_STYLE_CROSSOUT;
-  return SetRichTextProps(EP_CROSSOUT, NULL, &WordProps);
+  return SetRichTextProps(EP_CROSSOUT, nullptr, &WordProps);
 }
 
 FX_BOOL CFX_Edit::SetRichTextCharSpace(FX_FLOAT fCharSpace) {
   CPVT_WordProps WordProps;
   WordProps.fCharSpace = fCharSpace;
-  return SetRichTextProps(EP_CHARSPACE, NULL, &WordProps);
+  return SetRichTextProps(EP_CHARSPACE, nullptr, &WordProps);
 }
 
 FX_BOOL CFX_Edit::SetRichTextHorzScale(int32_t nHorzScale) {
   CPVT_WordProps WordProps;
   WordProps.nHorzScale = nHorzScale;
-  return SetRichTextProps(EP_HORZSCALE, NULL, &WordProps);
+  return SetRichTextProps(EP_HORZSCALE, nullptr, &WordProps);
 }
 
 FX_BOOL CFX_Edit::SetRichTextLineLeading(FX_FLOAT fLineLeading) {
   CPVT_SecProps SecProps;
   SecProps.fLineLeading = fLineLeading;
-  return SetRichTextProps(EP_LINELEADING, &SecProps, NULL);
+  return SetRichTextProps(EP_LINELEADING, &SecProps, nullptr);
 }
 
 FX_BOOL CFX_Edit::SetRichTextLineIndent(FX_FLOAT fLineIndent) {
   CPVT_SecProps SecProps;
   SecProps.fLineIndent = fLineIndent;
-  return SetRichTextProps(EP_LINEINDENT, &SecProps, NULL);
+  return SetRichTextProps(EP_LINEINDENT, &SecProps, nullptr);
 }
 
 FX_BOOL CFX_Edit::SetRichTextAlignment(int32_t nAlignment) {
   CPVT_SecProps SecProps;
   SecProps.nAlignment = nAlignment;
-  return SetRichTextProps(EP_ALIGNMENT, &SecProps, NULL);
+  return SetRichTextProps(EP_ALIGNMENT, &SecProps, nullptr);
 }
 
 FX_BOOL CFX_Edit::SetRichTextProps(EDIT_PROPS_E eProps,
@@ -2961,7 +2961,7 @@ void CFX_Edit::EndGroupUndo() {
   m_Undo.AddItem(m_pGroupUndoItem);
   if (m_bOprNotify && m_pOprNotify)
     m_pOprNotify->OnAddUndo(m_pGroupUndoItem);
-  m_pGroupUndoItem = NULL;
+  m_pGroupUndoItem = nullptr;
 }
 
 void CFX_Edit::AddEditUndoItem(CFX_Edit_UndoItem* pEditUndoItem) {
diff --git a/fpdfsdk/fxedit/fxet_list.cpp b/fpdfsdk/fxedit/fxet_list.cpp
index 383b84f27f..1385d57680 100644
--- a/fpdfsdk/fxedit/fxet_list.cpp
+++ b/fpdfsdk/fxedit/fxet_list.cpp
@@ -74,7 +74,7 @@ CFX_WideString CFX_ListItem::GetText() const {
 }
 
 CFX_List::CFX_List()
-    : m_fFontSize(0.0f), m_pFontMap(NULL), m_bMultiple(FALSE) {}
+    : m_fFontSize(0.0f), m_pFontMap(nullptr), m_bMultiple(FALSE) {}
 
 CFX_List::~CFX_List() {
   Empty();
@@ -125,7 +125,7 @@ IFX_Edit* CFX_List::GetItemEdit(int32_t nIndex) const {
     return pListItem->GetEdit();
   }
 
-  return NULL;
+  return nullptr;
 }
 
 int32_t CFX_List::GetCount() const {
@@ -378,7 +378,7 @@ void CPLST_Select::Done() {
 }
 
 CFX_ListCtrl::CFX_ListCtrl()
-    : m_pNotify(NULL),
+    : m_pNotify(nullptr),
       m_bNotifyFlag(FALSE),
       m_ptScrollPos(0.0f, 0.0f),
       m_nSelItem(-1),
diff --git a/fpdfsdk/fxedit/fxet_pageobjs.cpp b/fpdfsdk/fxedit/fxet_pageobjs.cpp
index f12fffb373..29ad135bca 100644
--- a/fpdfsdk/fxedit/fxet_pageobjs.cpp
+++ b/fpdfsdk/fxedit/fxet_pageobjs.cpp
@@ -190,7 +190,7 @@ void IFX_Edit::DrawUnderline(CFX_RenderDevice* pDevice,
         pathUnderline.AppendRect(rcUnderline.left, rcUnderline.bottom,
                                  rcUnderline.right, rcUnderline.top);
 
-        pDevice->DrawPath(&pathUnderline, pUser2Device, NULL, color, 0,
+        pDevice->DrawPath(&pathUnderline, pUser2Device, nullptr, color, 0,
                           FXFILL_WINDING);
       }
     }
@@ -275,7 +275,7 @@ void IFX_Edit::DrawEdit(CFX_RenderDevice* pDevice,
                 word.ptWord.x, line.ptLine.y + line.fLineDescent,
                 word.ptWord.x + word.fWidth, line.ptLine.y + line.fLineAscent);
 
-            pDevice->DrawPath(&pathSelBK, pUser2Device, NULL, crSelBK, 0,
+            pDevice->DrawPath(&pathSelBK, pUser2Device, nullptr, crSelBK, 0,
                               FXFILL_WINDING);
           }
         }
@@ -387,7 +387,7 @@ void IFX_Edit::DrawRichEdit(CFX_RenderDevice* pDevice,
                                word.ptWord.x + word.fWidth + ptOffset.x,
                                line.ptLine.y + line.fLineAscent + ptOffset.y);
 
-          pDevice->DrawPath(&pathSelBK, pUser2Device, NULL, crSelBK, 0,
+          pDevice->DrawPath(&pathSelBK, pUser2Device, nullptr, crSelBK, 0,
                             FXFILL_WINDING);
         }
 
@@ -419,7 +419,7 @@ void IFX_Edit::DrawRichEdit(CFX_RenderDevice* pDevice,
           pathUnderline.AppendRect(rcUnderline.left, rcUnderline.bottom,
                                    rcUnderline.right, rcUnderline.top);
 
-          pDevice->DrawPath(&pathUnderline, pUser2Device, NULL, crCurText, 0,
+          pDevice->DrawPath(&pathUnderline, pUser2Device, nullptr, crCurText, 0,
                             FXFILL_WINDING);
         }
 
@@ -429,7 +429,7 @@ void IFX_Edit::DrawRichEdit(CFX_RenderDevice* pDevice,
           pathCrossout.AppendRect(rcCrossout.left, rcCrossout.bottom,
                                   rcCrossout.right, rcCrossout.top);
 
-          pDevice->DrawPath(&pathCrossout, pUser2Device, NULL, crCurText, 0,
+          pDevice->DrawPath(&pathCrossout, pUser2Device, nullptr, crCurText, 0,
                             FXFILL_WINDING);
         }
 
diff --git a/fpdfsdk/fxedit/include/fx_edit.h b/fpdfsdk/fxedit/include/fx_edit.h
index 5f0283f06f..710c06f809 100644
--- a/fpdfsdk/fxedit/include/fx_edit.h
+++ b/fpdfsdk/fxedit/include/fx_edit.h
@@ -366,23 +366,23 @@ class IFX_Edit {
   // put text into edit.
   virtual void SetText(const FX_WCHAR* text,
                        int32_t charset = DEFAULT_CHARSET,
-                       const CPVT_SecProps* pSecProps = NULL,
-                       const CPVT_WordProps* pWordProps = NULL) = 0;
+                       const CPVT_SecProps* pSecProps = nullptr,
+                       const CPVT_WordProps* pWordProps = nullptr) = 0;
 
   // insert a word into the edit.
   virtual FX_BOOL InsertWord(uint16_t word,
                              int32_t charset = DEFAULT_CHARSET,
-                             const CPVT_WordProps* pWordProps = NULL) = 0;
+                             const CPVT_WordProps* pWordProps = nullptr) = 0;
 
   // insert a return into the edit.
-  virtual FX_BOOL InsertReturn(const CPVT_SecProps* pSecProps = NULL,
-                               const CPVT_WordProps* pWordProps = NULL) = 0;
+  virtual FX_BOOL InsertReturn(const CPVT_SecProps* pSecProps = nullptr,
+                               const CPVT_WordProps* pWordProps = nullptr) = 0;
 
   // insert text into the edit.
   virtual FX_BOOL InsertText(const FX_WCHAR* text,
                              int32_t charset = DEFAULT_CHARSET,
-                             const CPVT_SecProps* pSecProps = NULL,
-                             const CPVT_WordProps* pWordProps = NULL) = 0;
+                             const CPVT_SecProps* pSecProps = nullptr,
+                             const CPVT_WordProps* pWordProps = nullptr) = 0;
 
   // do backspace operation.
   virtual FX_BOOL Backspace() = 0;
@@ -476,13 +476,13 @@ class IFX_Edit {
   static CFX_ByteString GetEditAppearanceStream(
       IFX_Edit* pEdit,
       const CFX_FloatPoint& ptOffset,
-      const CPVT_WordRange* pRange = NULL,
+      const CPVT_WordRange* pRange = nullptr,
       FX_BOOL bContinuous = TRUE,
       uint16_t SubWord = 0);
   static CFX_ByteString GetSelectAppearanceStream(
       IFX_Edit* pEdit,
       const CFX_FloatPoint& ptOffset,
-      const CPVT_WordRange* pRange = NULL);
+      const CPVT_WordRange* pRange = nullptr);
   static void DrawEdit(CFX_RenderDevice* pDevice,
                        CFX_Matrix* pUser2Device,
                        IFX_Edit* pEdit,
diff --git a/fpdfsdk/fxedit/include/fxet_edit.h b/fpdfsdk/fxedit/include/fxet_edit.h
index c7500a05fb..71431de90a 100644
--- a/fpdfsdk/fxedit/include/fxet_edit.h
+++ b/fpdfsdk/fxedit/include/fxet_edit.h
@@ -102,7 +102,7 @@ class CFX_Edit_LineRectArray {
 
   CFX_Edit_LineRect* GetAt(int32_t nIndex) const {
     if (nIndex < 0 || nIndex >= m_LineRects.GetSize())
-      return NULL;
+      return nullptr;
 
     return m_LineRects.GetAt(nIndex);
   }
@@ -138,7 +138,7 @@ class CFX_Edit_RectArray {
 
   CFX_FloatRect* GetAt(int32_t nIndex) const {
     if (nIndex < 0 || nIndex >= m_Rects.GetSize())
-      return NULL;
+      return nullptr;
 
     return m_Rects.GetAt(nIndex);
   }
@@ -570,20 +570,20 @@ class CFX_Edit : public IFX_Edit {
   void OnVK_END(FX_BOOL bShift, FX_BOOL bCtrl) override;
   void SetText(const FX_WCHAR* text,
                int32_t charset = DEFAULT_CHARSET,
-               const CPVT_SecProps* pSecProps = NULL,
-               const CPVT_WordProps* pWordProps = NULL) override;
+               const CPVT_SecProps* pSecProps = nullptr,
+               const CPVT_WordProps* pWordProps = nullptr) override;
   FX_BOOL InsertWord(uint16_t word,
                      int32_t charset = DEFAULT_CHARSET,
-                     const CPVT_WordProps* pWordProps = NULL) override;
-  FX_BOOL InsertReturn(const CPVT_SecProps* pSecProps = NULL,
-                       const CPVT_WordProps* pWordProps = NULL) override;
+                     const CPVT_WordProps* pWordProps = nullptr) override;
+  FX_BOOL InsertReturn(const CPVT_SecProps* pSecProps = nullptr,
+                       const CPVT_WordProps* pWordProps = nullptr) override;
   FX_BOOL Backspace() override;
   FX_BOOL Delete() override;
   FX_BOOL Clear() override;
   FX_BOOL InsertText(const FX_WCHAR* text,
                      int32_t charset = DEFAULT_CHARSET,
-                     const CPVT_SecProps* pSecProps = NULL,
-                     const CPVT_WordProps* pWordProps = NULL) override;
+                     const CPVT_SecProps* pSecProps = nullptr,
+                     const CPVT_WordProps* pWordProps = nullptr) override;
   FX_BOOL Redo() override;
   FX_BOOL Undo() override;
   int32_t WordPlaceToWordIndex(const CPVT_WordPlace& place) const override;
@@ -701,8 +701,8 @@ class CFX_Edit : public IFX_Edit {
   inline CFX_FloatRect EditToVT(const CFX_FloatRect& rect) const;
 
   void Refresh(REFRESH_PLAN_E ePlan,
-               const CPVT_WordRange* pRange1 = NULL,
-               const CPVT_WordRange* pRange2 = NULL);
+               const CPVT_WordRange* pRange1 = nullptr,
+               const CPVT_WordRange* pRange2 = nullptr);
   void RefreshPushLineRects(const CPVT_WordRange& wr);
   void RefreshPushRandomRects(const CPVT_WordRange& wr);
 
diff --git a/fpdfsdk/fxedit/include/fxet_list.h b/fpdfsdk/fxedit/include/fxet_list.h
index 58aa94c5b6..ab4605169b 100644
--- a/fpdfsdk/fxedit/include/fxet_list.h
+++ b/fpdfsdk/fxedit/include/fxet_list.h
@@ -193,7 +193,7 @@ class CLST_ArrayTemplate : public CFX_ArrayTemplate<TYPE> {
   TYPE GetAt(int32_t nIndex) const {
     if (nIndex >= 0 && nIndex < CFX_ArrayTemplate<TYPE>::GetSize())
       return CFX_ArrayTemplate<TYPE>::GetAt(nIndex);
-    return NULL;
+    return nullptr;
   }
   void RemoveAt(int32_t nIndex) {
     if (nIndex >= 0 && nIndex < CFX_ArrayTemplate<TYPE>::GetSize())
diff --git a/fpdfsdk/include/fsdk_annothandler.h b/fpdfsdk/include/fsdk_annothandler.h
index a9c76e2523..b36fe372b2 100644
--- a/fpdfsdk/include/fsdk_annothandler.h
+++ b/fpdfsdk/include/fsdk_annothandler.h
@@ -142,7 +142,7 @@ class IPDFSDK_AnnotHandler {
 class CPDFSDK_BFAnnotHandler : public IPDFSDK_AnnotHandler {
  public:
   explicit CPDFSDK_BFAnnotHandler(CPDFDoc_Environment* pApp)
-      : m_pApp(pApp), m_pFormFiller(NULL) {}
+      : m_pApp(pApp), m_pFormFiller(nullptr) {}
   ~CPDFSDK_BFAnnotHandler() override {}
 
   // IPDFSDK_AnnotHandler
@@ -255,7 +255,7 @@ class CPDFSDK_XFAAnnotHandler : public IPDFSDK_AnnotHandler {
   virtual FX_BOOL CanAnswer(CPDFSDK_Annot* pAnnot);
 
   virtual CPDFSDK_Annot* NewAnnot(CPDF_Annot* pAnnot, CPDFSDK_PageView* pPage) {
-    return NULL;
+    return nullptr;
   }
 
   virtual CPDFSDK_Annot* NewAnnot(CXFA_FFWidget* pAnnot,
diff --git a/fpdfsdk/include/fsdk_baseform.h b/fpdfsdk/include/fsdk_baseform.h
index 5e00e16402..c7a7e742d3 100644
--- a/fpdfsdk/include/fsdk_baseform.h
+++ b/fpdfsdk/include/fsdk_baseform.h
@@ -281,7 +281,7 @@ class CPDFSDK_InterForm : public IPDF_FormNotify {
   FX_BOOL OnKeyStrokeCommit(CPDF_FormField* pFormField,
                             const CFX_WideString& csValue);
   FX_BOOL OnValidate(CPDF_FormField* pFormField, const CFX_WideString& csValue);
-  void OnCalculate(CPDF_FormField* pFormField = NULL);
+  void OnCalculate(CPDF_FormField* pFormField = nullptr);
   CFX_WideString OnFormat(CPDF_FormField* pFormField, FX_BOOL& bFormated);
 
   void ResetFieldAppearance(CPDF_FormField* pFormField,
diff --git a/fpdfsdk/include/fsdk_mgr.h b/fpdfsdk/include/fsdk_mgr.h
index a47f230c92..bf11a23765 100644
--- a/fpdfsdk/include/fsdk_mgr.h
+++ b/fpdfsdk/include/fsdk_mgr.h
@@ -111,13 +111,13 @@ class CPDFDoc_Environment final {
   FPDF_PAGE FFI_GetPage(FPDF_DOCUMENT document, int nPageIndex) {
     if (m_pInfo && m_pInfo->FFI_GetPage)
       return m_pInfo->FFI_GetPage(m_pInfo, document, nPageIndex);
-    return NULL;
+    return nullptr;
   }
 
   FPDF_PAGE FFI_GetCurrentPage(FPDF_DOCUMENT document) {
     if (m_pInfo && m_pInfo->FFI_GetCurrentPage)
       return m_pInfo->FFI_GetCurrentPage(m_pInfo, document);
-    return NULL;
+    return nullptr;
   }
 
   int FFI_GetRotation(FPDF_PAGE page) {
@@ -181,7 +181,7 @@ class CPDFDoc_Environment final {
 
   CFX_WideString FFI_GetPlatform() {
     if (m_pInfo && m_pInfo->FFI_GetPlatform) {
-      int nRequiredLen = m_pInfo->FFI_GetPlatform(m_pInfo, NULL, 0);
+      int nRequiredLen = m_pInfo->FFI_GetPlatform(m_pInfo, nullptr, 0);
       if (nRequiredLen <= 0)
         return L"";
 
@@ -275,7 +275,7 @@ class CPDFDoc_Environment final {
                                  const char* mode) {
     if (m_pInfo && m_pInfo->FFI_OpenFile)
       return m_pInfo->FFI_OpenFile(m_pInfo, fileType, wsURL, mode);
-    return NULL;
+    return nullptr;
   }
 
   CFX_WideString FFI_GetFilePath(FPDF_FILEHANDLER* pFileHandler) const {
@@ -296,7 +296,7 @@ class CPDFDoc_Environment final {
 
       return new CFPDF_FileStream(fileHandler);
     }
-    return NULL;
+    return nullptr;
   }
 
   CFX_WideString FFI_PostRequestURL(const FX_WCHAR* wsURL,
@@ -361,7 +361,7 @@ class CPDFDoc_Environment final {
 
   CFX_WideString FFI_GetLanguage() {
     if (m_pInfo && m_pInfo->FFI_GetLanguage) {
-      int nRequiredLen = m_pInfo->FFI_GetLanguage(m_pInfo, NULL, 0);
+      int nRequiredLen = m_pInfo->FFI_GetLanguage(m_pInfo, nullptr, 0);
       if (nRequiredLen <= 0)
         return L"";
 
diff --git a/fpdfsdk/javascript/Document.cpp b/fpdfsdk/javascript/Document.cpp
index 12d8c2df31..076e99849e 100644
--- a/fpdfsdk/javascript/Document.cpp
+++ b/fpdfsdk/javascript/Document.cpp
@@ -147,8 +147,8 @@ void CJS_Document::InitInstance(IJS_Runtime* pIRuntime) {
 
 Document::Document(CJS_Object* pJSObject)
     : CJS_EmbedObj(pJSObject),
-      m_isolate(NULL),
-      m_pDocument(NULL),
+      m_isolate(nullptr),
+      m_pDocument(nullptr),
       m_cwBaseURL(L""),
       m_bDelay(FALSE) {}
 
@@ -715,8 +715,8 @@ FX_BOOL Document::mailDoc(IJS_Context* cc,
 
   pRuntime->BeginBlock();
   CPDFDoc_Environment* pEnv = pRuntime->GetReaderApp();
-  pEnv->JS_docmailForm(NULL, 0, bUI, cTo.c_str(), cSubject.c_str(), cCc.c_str(),
-                       cBcc.c_str(), cMsg.c_str());
+  pEnv->JS_docmailForm(nullptr, 0, bUI, cTo.c_str(), cSubject.c_str(),
+                       cCc.c_str(), cBcc.c_str(), cMsg.c_str());
   pRuntime->EndBlock();
 
   return TRUE;
diff --git a/fpdfsdk/javascript/Field.cpp b/fpdfsdk/javascript/Field.cpp
index 5808982b43..43bc89e26e 100644
--- a/fpdfsdk/javascript/Field.cpp
+++ b/fpdfsdk/javascript/Field.cpp
@@ -122,12 +122,12 @@ void CJS_Field::InitInstance(IJS_Runtime* pIRuntime) {
 
 Field::Field(CJS_Object* pJSObject)
     : CJS_EmbedObj(pJSObject),
-      m_pJSDoc(NULL),
-      m_pDocument(NULL),
+      m_pJSDoc(nullptr),
+      m_pDocument(nullptr),
       m_nFormControlIndex(-1),
       m_bCanSet(FALSE),
       m_bDelay(FALSE),
-      m_isolate(NULL) {}
+      m_isolate(nullptr) {}
 
 Field::~Field() {}
 
@@ -262,16 +262,16 @@ void Field::UpdateFormControl(CPDFSDK_Document* pDocument,
         if (bFormated)
           pWidget->ResetAppearance(sValue.c_str(), FALSE);
         else
-          pWidget->ResetAppearance(NULL, FALSE);
+          pWidget->ResetAppearance(nullptr, FALSE);
       } else {
-        pWidget->ResetAppearance(NULL, FALSE);
+        pWidget->ResetAppearance(nullptr, FALSE);
       }
     }
 
     if (bRefresh) {
       CPDFSDK_InterForm* pInterForm = pWidget->GetInterForm();
       CPDFSDK_Document* pDoc = pInterForm->GetDocument();
-      pDoc->UpdateAllViews(NULL, pWidget);
+      pDoc->UpdateAllViews(nullptr, pWidget);
     }
   }
 
@@ -299,7 +299,7 @@ FX_BOOL Field::ValueIsOccur(CPDF_FormField* pFormField,
 CPDF_FormControl* Field::GetSmartFieldControl(CPDF_FormField* pFormField) {
   if (!pFormField->CountControls() ||
       m_nFormControlIndex >= pFormField->CountControls())
-    return NULL;
+    return nullptr;
 
   if (m_nFormControlIndex < 0)
     return pFormField->GetControl(0);
@@ -2956,7 +2956,7 @@ FX_BOOL Field::buttonGetIcon(IJS_Context* cc,
   CJS_Icon* pJS_Icon = (CJS_Icon*)FXJS_GetPrivate(pRuntime->GetIsolate(), pObj);
   Icon* pIcon = (Icon*)pJS_Icon->GetEmbedObject();
 
-  CPDF_Stream* pIconStream = NULL;
+  CPDF_Stream* pIconStream = nullptr;
   if (nface == 0)
     pIconStream = pFormControl->GetNormalIcon();
   else if (nface == 1)
@@ -3254,7 +3254,7 @@ FX_BOOL Field::setFocus(IJS_Context* cc,
 
   CPDFSDK_InterForm* pInterForm =
       (CPDFSDK_InterForm*)m_pDocument->GetInterForm();
-  CPDFSDK_Widget* pWidget = NULL;
+  CPDFSDK_Widget* pWidget = nullptr;
   if (nCount == 1) {
     pWidget = pInterForm->GetWidget(pFormField->GetControl(0));
   } else {
@@ -3343,7 +3343,7 @@ FX_BOOL Field::source(IJS_Context* cc,
                       CJS_PropValue& vp,
                       CFX_WideString& sError) {
   if (vp.IsGetting()) {
-    vp << (CJS_Object*)NULL;
+    vp << (CJS_Object*)nullptr;
   }
 
   return TRUE;
diff --git a/fpdfsdk/javascript/Icon.cpp b/fpdfsdk/javascript/Icon.cpp
index 7dde8bf0b5..031ec4f63a 100644
--- a/fpdfsdk/javascript/Icon.cpp
+++ b/fpdfsdk/javascript/Icon.cpp
@@ -23,7 +23,7 @@ END_JS_STATIC_METHOD()
 IMPLEMENT_JS_CLASS(CJS_Icon, Icon)
 
 Icon::Icon(CJS_Object* pJSObject)
-    : CJS_EmbedObj(pJSObject), m_pIconStream(NULL), m_swIconName(L"") {}
+    : CJS_EmbedObj(pJSObject), m_pIconStream(nullptr), m_swIconName(L"") {}
 
 Icon::~Icon() {}
 
diff --git a/fpdfsdk/javascript/JS_EventHandler.cpp b/fpdfsdk/javascript/JS_EventHandler.cpp
index 5984946f6d..8dc1b8270c 100644
--- a/fpdfsdk/javascript/JS_EventHandler.cpp
+++ b/fpdfsdk/javascript/JS_EventHandler.cpp
@@ -18,24 +18,24 @@ CJS_EventHandler::CJS_EventHandler(CJS_Context* pContext)
     : m_pJSContext(pContext),
       m_eEventType(JET_UNKNOWN),
       m_bValid(FALSE),
-      m_pWideStrChange(NULL),
+      m_pWideStrChange(nullptr),
       m_nCommitKey(-1),
       m_bKeyDown(FALSE),
       m_bModifier(FALSE),
       m_bShift(FALSE),
-      m_pISelEnd(NULL),
+      m_pISelEnd(nullptr),
       m_nSelEndDu(0),
-      m_pISelStart(NULL),
+      m_pISelStart(nullptr),
       m_nSelStartDu(0),
       m_bWillCommit(FALSE),
-      m_pValue(NULL),
+      m_pValue(nullptr),
       m_bFieldFull(FALSE),
-      m_pbRc(NULL),
+      m_pbRc(nullptr),
       m_bRcDu(FALSE),
-      m_pSourceDoc(NULL),
-      m_pTargetBookMark(NULL),
-      m_pTargetDoc(NULL),
-      m_pTargetAnnot(NULL) {}
+      m_pSourceDoc(nullptr),
+      m_pTargetBookMark(nullptr),
+      m_pTargetDoc(nullptr),
+      m_pTargetAnnot(nullptr) {}
 
 CJS_EventHandler::~CJS_EventHandler() {}
 
@@ -382,27 +382,27 @@ void CJS_EventHandler::Initial(JS_EVENT_T type) {
 
   m_strTargetName = L"";
   m_strSourceName = L"";
-  m_pWideStrChange = NULL;
+  m_pWideStrChange = nullptr;
   m_WideStrChangeDu = L"";
   m_WideStrChangeEx = L"";
   m_nCommitKey = -1;
   m_bKeyDown = FALSE;
   m_bModifier = FALSE;
   m_bShift = FALSE;
-  m_pISelEnd = NULL;
+  m_pISelEnd = nullptr;
   m_nSelEndDu = 0;
-  m_pISelStart = NULL;
+  m_pISelStart = nullptr;
   m_nSelStartDu = 0;
   m_bWillCommit = FALSE;
-  m_pValue = NULL;
+  m_pValue = nullptr;
   m_bFieldFull = FALSE;
-  m_pbRc = NULL;
+  m_pbRc = nullptr;
   m_bRcDu = FALSE;
 
-  m_pSourceDoc = NULL;
-  m_pTargetBookMark = NULL;
-  m_pTargetDoc = NULL;
-  m_pTargetAnnot = NULL;
+  m_pSourceDoc = nullptr;
+  m_pTargetBookMark = nullptr;
+  m_pTargetDoc = nullptr;
+  m_pTargetAnnot = nullptr;
 
   m_bValid = TRUE;
 }
diff --git a/fpdfsdk/javascript/JS_GlobalData.cpp b/fpdfsdk/javascript/JS_GlobalData.cpp
index b34bf0907e..aaa25ff474 100644
--- a/fpdfsdk/javascript/JS_GlobalData.cpp
+++ b/fpdfsdk/javascript/JS_GlobalData.cpp
@@ -280,7 +280,7 @@ CJS_GlobalData_Element* CJS_GlobalData::GetAt(int index) const {
 }
 
 void CJS_GlobalData::LoadGlobalPersistentVariables() {
-  uint8_t* pBuffer = NULL;
+  uint8_t* pBuffer = nullptr;
   int32_t nLength = 0;
 
   LoadFileBuffer(m_sFilePath.c_str(), pBuffer, nLength);
diff --git a/fpdfsdk/javascript/JS_Object.cpp b/fpdfsdk/javascript/JS_Object.cpp
index 7dc91a7291..6339bb7359 100644
--- a/fpdfsdk/javascript/JS_Object.cpp
+++ b/fpdfsdk/javascript/JS_Object.cpp
@@ -31,7 +31,7 @@ int FXJS_MsgBox(CPDFDoc_Environment* pApp,
 CJS_EmbedObj::CJS_EmbedObj(CJS_Object* pJSObject) : m_pJSObject(pJSObject) {}
 
 CJS_EmbedObj::~CJS_EmbedObj() {
-  m_pJSObject = NULL;
+  m_pJSObject = nullptr;
 }
 
 int CJS_EmbedObj::MsgBox(CPDFDoc_Environment* pApp,
@@ -87,7 +87,7 @@ void CJS_Object::Alert(CJS_Context* pContext, const FX_WCHAR* swMsg) {
   if (pContext->IsMsgBoxEnabled()) {
     CPDFDoc_Environment* pApp = pContext->GetReaderApp();
     if (pApp)
-      pApp->JS_appAlert(swMsg, NULL, 0, 3);
+      pApp->JS_appAlert(swMsg, nullptr, 0, 3);
   }
 }
 
diff --git a/fpdfsdk/javascript/JS_Value.cpp b/fpdfsdk/javascript/JS_Value.cpp
index b01ee586e1..1b8964bd00 100644
--- a/fpdfsdk/javascript/JS_Value.cpp
+++ b/fpdfsdk/javascript/JS_Value.cpp
@@ -753,7 +753,7 @@ int _DateFromTime(double t) {
 double JS_GetDateTime() {
   if (!FSDK_IsSandBoxPolicyEnabled(FPDF_POLICY_MACHINETIME_ACCESS))
     return 0;
-  time_t t = time(NULL);
+  time_t t = time(nullptr);
   struct tm* pTm = localtime(&t);
 
   int year = pTm->tm_year + 1900;
diff --git a/fpdfsdk/javascript/cjs_runtime.cpp b/fpdfsdk/javascript/cjs_runtime.cpp
index 2c0ed32bd6..69d61dc940 100644
--- a/fpdfsdk/javascript/cjs_runtime.cpp
+++ b/fpdfsdk/javascript/cjs_runtime.cpp
@@ -52,9 +52,9 @@ CJS_Runtime* CJS_Runtime::FromContext(const IJS_Context* cc) {
 
 CJS_Runtime::CJS_Runtime(CPDFDoc_Environment* pApp)
     : m_pApp(pApp),
-      m_pDocument(NULL),
+      m_pDocument(nullptr),
       m_bBlocking(FALSE),
-      m_isolate(NULL),
+      m_isolate(nullptr),
       m_isolateManaged(false) {
 #ifndef PDF_ENABLE_XFA
   IPDF_JSPLATFORM* pPlatform = m_pApp->GetFormFillInfo()->m_pJsPlatform;
diff --git a/fpdfsdk/javascript/global.cpp b/fpdfsdk/javascript/global.cpp
index 043bd290ac..32498e474c 100644
--- a/fpdfsdk/javascript/global.cpp
+++ b/fpdfsdk/javascript/global.cpp
@@ -94,7 +94,7 @@ void CJS_Global::InitInstance(IJS_Runtime* pIRuntime) {
 }
 
 JSGlobalAlternate::JSGlobalAlternate(CJS_Object* pJSObject)
-    : CJS_EmbedObj(pJSObject), m_pApp(NULL) {}
+    : CJS_EmbedObj(pJSObject), m_pApp(nullptr) {}
 
 JSGlobalAlternate::~JSGlobalAlternate() {
   DestroyGlobalPersisitentVariables();
@@ -232,14 +232,14 @@ void JSGlobalAlternate::UpdateGlobalPersistentVariables() {
         SetGlobalVariables(pData->data.sKey, JS_GLOBALDATA_TYPE_NUMBER,
                            pData->data.dData, false, "",
                            v8::Local<v8::Object>(), pData->bPersistent == 1);
-        FXJS_PutObjectNumber(NULL, m_pJSObject->ToV8Object(),
+        FXJS_PutObjectNumber(nullptr, m_pJSObject->ToV8Object(),
                              pData->data.sKey.UTF8Decode(), pData->data.dData);
         break;
       case JS_GLOBALDATA_TYPE_BOOLEAN:
         SetGlobalVariables(pData->data.sKey, JS_GLOBALDATA_TYPE_BOOLEAN, 0,
                            (bool)(pData->data.bData == 1), "",
                            v8::Local<v8::Object>(), pData->bPersistent == 1);
-        FXJS_PutObjectBoolean(NULL, m_pJSObject->ToV8Object(),
+        FXJS_PutObjectBoolean(nullptr, m_pJSObject->ToV8Object(),
                               pData->data.sKey.UTF8Decode(),
                               (bool)(pData->data.bData == 1));
         break;
@@ -247,26 +247,27 @@ void JSGlobalAlternate::UpdateGlobalPersistentVariables() {
         SetGlobalVariables(pData->data.sKey, JS_GLOBALDATA_TYPE_STRING, 0,
                            false, pData->data.sData, v8::Local<v8::Object>(),
                            pData->bPersistent == 1);
-        FXJS_PutObjectString(NULL, m_pJSObject->ToV8Object(),
+        FXJS_PutObjectString(nullptr, m_pJSObject->ToV8Object(),
                              pData->data.sKey.UTF8Decode(),
                              pData->data.sData.UTF8Decode());
         break;
       case JS_GLOBALDATA_TYPE_OBJECT: {
         v8::Isolate* pRuntime = m_pJSObject->ToV8Object()->GetIsolate();
-        v8::Local<v8::Object> pObj = FXJS_NewFxDynamicObj(pRuntime, NULL, -1);
+        v8::Local<v8::Object> pObj =
+            FXJS_NewFxDynamicObj(pRuntime, nullptr, -1);
 
         PutObjectProperty(pObj, &pData->data);
 
         SetGlobalVariables(pData->data.sKey, JS_GLOBALDATA_TYPE_OBJECT, 0,
                            false, "", pObj, pData->bPersistent == 1);
-        FXJS_PutObjectObject(NULL, m_pJSObject->ToV8Object(),
+        FXJS_PutObjectObject(nullptr, m_pJSObject->ToV8Object(),
                              pData->data.sKey.UTF8Decode(), pObj);
       } break;
       case JS_GLOBALDATA_TYPE_NULL:
         SetGlobalVariables(pData->data.sKey, JS_GLOBALDATA_TYPE_NULL, 0, false,
                            "", v8::Local<v8::Object>(),
                            pData->bPersistent == 1);
-        FXJS_PutObjectNull(NULL, m_pJSObject->ToV8Object(),
+        FXJS_PutObjectNull(nullptr, m_pJSObject->ToV8Object(),
                            pData->data.sKey.UTF8Decode());
         break;
     }
@@ -373,26 +374,27 @@ void JSGlobalAlternate::PutObjectProperty(v8::Local<v8::Object> pObj,
     CJS_KeyValue* pObjData = pData->objData.GetAt(i);
     switch (pObjData->nType) {
       case JS_GLOBALDATA_TYPE_NUMBER:
-        FXJS_PutObjectNumber(NULL, pObj, pObjData->sKey.UTF8Decode(),
+        FXJS_PutObjectNumber(nullptr, pObj, pObjData->sKey.UTF8Decode(),
                              pObjData->dData);
         break;
       case JS_GLOBALDATA_TYPE_BOOLEAN:
-        FXJS_PutObjectBoolean(NULL, pObj, pObjData->sKey.UTF8Decode(),
+        FXJS_PutObjectBoolean(nullptr, pObj, pObjData->sKey.UTF8Decode(),
                               pObjData->bData == 1);
         break;
       case JS_GLOBALDATA_TYPE_STRING:
-        FXJS_PutObjectString(NULL, pObj, pObjData->sKey.UTF8Decode(),
+        FXJS_PutObjectString(nullptr, pObj, pObjData->sKey.UTF8Decode(),
                              pObjData->sData.UTF8Decode());
         break;
       case JS_GLOBALDATA_TYPE_OBJECT: {
         v8::Isolate* pRuntime = m_pJSObject->ToV8Object()->GetIsolate();
         v8::Local<v8::Object> pNewObj =
-            FXJS_NewFxDynamicObj(pRuntime, NULL, -1);
+            FXJS_NewFxDynamicObj(pRuntime, nullptr, -1);
         PutObjectProperty(pNewObj, pObjData);
-        FXJS_PutObjectObject(NULL, pObj, pObjData->sKey.UTF8Decode(), pNewObj);
+        FXJS_PutObjectObject(nullptr, pObj, pObjData->sKey.UTF8Decode(),
+                             pNewObj);
       } break;
       case JS_GLOBALDATA_TYPE_NULL:
-        FXJS_PutObjectNull(NULL, pObj, pObjData->sKey.UTF8Decode());
+        FXJS_PutObjectNull(nullptr, pObj, pObjData->sKey.UTF8Decode());
         break;
     }
   }
@@ -447,7 +449,7 @@ FX_BOOL JSGlobalAlternate::SetGlobalVariables(const CFX_ByteString& propname,
     return TRUE;
   }
 
-  JSGlobalData* pNewData = NULL;
+  JSGlobalData* pNewData = nullptr;
 
   switch (nType) {
     case JS_GLOBALDATA_TYPE_NUMBER: {
diff --git a/fpdfsdk/jsapi/fxjs_v8.cpp b/fpdfsdk/jsapi/fxjs_v8.cpp
index 73f6bbf4fb..790d10b602 100644
--- a/fpdfsdk/jsapi/fxjs_v8.cpp
+++ b/fpdfsdk/jsapi/fxjs_v8.cpp
@@ -314,7 +314,7 @@ void FXJS_InitializeRuntime(
   v8::Isolate::Scope isolate_scope(pIsolate);
   v8::HandleScope handle_scope(pIsolate);
   v8::Local<v8::Context> v8Context =
-      v8::Context::New(pIsolate, NULL, GetGlobalObjectTemplate(pIsolate));
+      v8::Context::New(pIsolate, nullptr, GetGlobalObjectTemplate(pIsolate));
   v8::Context::Scope context_scope(v8Context);
 
   FXJS_PerIsolateData::SetUp(pIsolate);
@@ -513,7 +513,7 @@ void FXJS_Error(v8::Isolate* pIsolate, const CFX_WideString& message) {
 
 const wchar_t* FXJS_GetTypeof(v8::Local<v8::Value> pObj) {
   if (pObj.IsEmpty())
-    return NULL;
+    return nullptr;
   if (pObj->IsString())
     return kFXJSValueNameString;
   if (pObj->IsNumber())
@@ -528,7 +528,7 @@ const wchar_t* FXJS_GetTypeof(v8::Local<v8::Value> pObj) {
     return kFXJSValueNameNull;
   if (pObj->IsUndefined())
     return kFXJSValueNameUndefined;
-  return NULL;
+  return nullptr;
 }
 
 void FXJS_SetPrivate(v8::Isolate* pIsolate,
@@ -572,7 +572,7 @@ void FXJS_FreePrivate(v8::Local<v8::Object> pObj) {
   if (pObj.IsEmpty() || !pObj->InternalFieldCount())
     return;
   FXJS_FreePrivate(pObj->GetAlignedPointerFromInternalField(0));
-  pObj->SetAlignedPointerInInternalField(0, NULL);
+  pObj->SetAlignedPointerInInternalField(0, nullptr);
 }
 
 v8::Local<v8::String> FXJS_WSToJSString(v8::Isolate* pIsolate,
diff --git a/fpdfsdk/pdfwindow/PWL_Caret.h b/fpdfsdk/pdfwindow/PWL_Caret.h
index a7cf1d4c05..0f002a2b4a 100644
--- a/fpdfsdk/pdfwindow/PWL_Caret.h
+++ b/fpdfsdk/pdfwindow/PWL_Caret.h
@@ -28,7 +28,7 @@ class CPWL_Caret : public CPWL_Wnd {
   void GetThisAppearanceStream(CFX_ByteTextBuf& sAppStream) override;
   void DrawThisAppearance(CFX_RenderDevice* pDevice,
                           CFX_Matrix* pUser2Device) override;
-  void InvalidateRect(CFX_FloatRect* pRect = NULL) override;
+  void InvalidateRect(CFX_FloatRect* pRect = nullptr) override;
   void SetVisible(FX_BOOL bVisible) override {}
   void TimerProc() override;
 
diff --git a/fpdfsdk/pdfwindow/PWL_ComboBox.cpp b/fpdfsdk/pdfwindow/PWL_ComboBox.cpp
index f49016123a..c5560228f1 100644
--- a/fpdfsdk/pdfwindow/PWL_ComboBox.cpp
+++ b/fpdfsdk/pdfwindow/PWL_ComboBox.cpp
@@ -169,7 +169,7 @@ void CPWL_CBButton::DrawThisAppearance(CFX_RenderDevice* pDevice,
       path.SetPoint(2, pt3.x, pt3.y, FXPT_LINETO);
       path.SetPoint(3, pt1.x, pt1.y, FXPT_LINETO);
 
-      pDevice->DrawPath(&path, pUser2Device, NULL,
+      pDevice->DrawPath(&path, pUser2Device, nullptr,
                         CPWL_Utils::PWLColorToFXColor(PWL_DEFAULT_BLACKCOLOR,
                                                       GetTransparency()),
                         0, FXFILL_ALTERNATE);
@@ -201,13 +201,13 @@ FX_BOOL CPWL_CBButton::OnLButtonUp(const CFX_FloatPoint& point,
 }
 
 CPWL_ComboBox::CPWL_ComboBox()
-    : m_pEdit(NULL),
-      m_pButton(NULL),
-      m_pList(NULL),
+    : m_pEdit(nullptr),
+      m_pButton(nullptr),
+      m_pList(nullptr),
       m_bPopup(FALSE),
       m_nPopupWhere(0),
       m_nSelectItem(-1),
-      m_pFillerNotify(NULL) {}
+      m_pFillerNotify(nullptr) {}
 
 CFX_ByteString CPWL_ComboBox::GetClassName() const {
   return "CPWL_ComboBox";
diff --git a/fpdfsdk/pdfwindow/PWL_Edit.cpp b/fpdfsdk/pdfwindow/PWL_Edit.cpp
index eec1fd98c7..21d4b033ab 100644
--- a/fpdfsdk/pdfwindow/PWL_Edit.cpp
+++ b/fpdfsdk/pdfwindow/PWL_Edit.cpp
@@ -388,7 +388,7 @@ void CPWL_Edit::DrawThisAppearance(CFX_RenderDevice* pDevice,
 
   CFX_FloatRect rcClip;
   CPVT_WordRange wrRange = m_pEdit->GetVisibleWordRange();
-  CPVT_WordRange* pRange = NULL;
+  CPVT_WordRange* pRange = nullptr;
 
   if (!HasFlag(PES_TEXTOVERFLOW)) {
     rcClip = GetClientRect();
@@ -938,7 +938,7 @@ void CPWL_Edit::GeneratePageObjects(
     const CFX_FloatPoint& ptOffset,
     CFX_ArrayTemplate<CPDF_TextObject*>& ObjArray) {
   IFX_Edit::GeneratePageObjects(
-      pObjectHolder, m_pEdit, ptOffset, NULL,
+      pObjectHolder, m_pEdit, ptOffset, nullptr,
       CPWL_Utils::PWLColorToFXColor(GetTextColor(), GetTransparency()),
       ObjArray);
 }
@@ -947,7 +947,7 @@ void CPWL_Edit::GeneratePageObjects(CPDF_PageObjectHolder* pObjectHolder,
                                     const CFX_FloatPoint& ptOffset) {
   CFX_ArrayTemplate<CPDF_TextObject*> ObjArray;
   IFX_Edit::GeneratePageObjects(
-      pObjectHolder, m_pEdit, ptOffset, NULL,
+      pObjectHolder, m_pEdit, ptOffset, nullptr,
       CPWL_Utils::PWLColorToFXColor(GetTextColor(), GetTransparency()),
       ObjArray);
 }
diff --git a/fpdfsdk/pdfwindow/PWL_EditCtrl.cpp b/fpdfsdk/pdfwindow/PWL_EditCtrl.cpp
index aa653929bd..e74a6d8b32 100644
--- a/fpdfsdk/pdfwindow/PWL_EditCtrl.cpp
+++ b/fpdfsdk/pdfwindow/PWL_EditCtrl.cpp
@@ -22,9 +22,9 @@
 
 CPWL_EditCtrl::CPWL_EditCtrl()
     : m_pEdit(IFX_Edit::NewEdit()),
-      m_pEditCaret(NULL),
+      m_pEditCaret(nullptr),
       m_bMouseDown(FALSE),
-      m_pEditNotify(NULL),
+      m_pEditNotify(nullptr),
       m_nCharSet(DEFAULT_CHARSET),
       m_nCodePage(0) {}
 
@@ -450,7 +450,7 @@ CPDF_Font* CPWL_EditCtrl::GetCaretFont() const {
   if (IPVT_FontMap* pFontMap = GetFontMap())
     return pFontMap->GetPDFFont(nFontIndex);
 
-  return NULL;
+  return nullptr;
 }
 
 FX_FLOAT CPWL_EditCtrl::GetCaretFontSize() const {
@@ -563,7 +563,7 @@ void CPWL_EditCtrl::IOnSetCaret(FX_BOOL bVisible,
   cInfo.ptHead = ptHead;
   cInfo.ptFoot = ptFoot;
 
-  OnNotify(this, PNM_SETCARETINFO, (intptr_t)&cInfo, (intptr_t)NULL);
+  OnNotify(this, PNM_SETCARETINFO, (intptr_t)&cInfo, (intptr_t) nullptr);
 }
 
 void CPWL_EditCtrl::IOnCaretChange(const CPVT_SecProps& secProps,
diff --git a/fpdfsdk/pdfwindow/PWL_FontMap.cpp b/fpdfsdk/pdfwindow/PWL_FontMap.cpp
index f73468bf2b..d4eab01cfd 100644
--- a/fpdfsdk/pdfwindow/PWL_FontMap.cpp
+++ b/fpdfsdk/pdfwindow/PWL_FontMap.cpp
@@ -35,13 +35,13 @@ const char* const g_sDEStandardFontName[] = {"Courier",
 }  // namespace
 
 CPWL_FontMap::CPWL_FontMap(CFX_SystemHandler* pSystemHandler)
-    : m_pPDFDoc(NULL), m_pSystemHandler(pSystemHandler) {
+    : m_pPDFDoc(nullptr), m_pSystemHandler(pSystemHandler) {
   ASSERT(m_pSystemHandler);
 }
 
 CPWL_FontMap::~CPWL_FontMap() {
   delete m_pPDFDoc;
-  m_pPDFDoc = NULL;
+  m_pPDFDoc = nullptr;
 
   Empty();
 }
@@ -68,7 +68,7 @@ CPDF_Font* CPWL_FontMap::GetPDFFont(int32_t nFontIndex) {
     }
   }
 
-  return NULL;
+  return nullptr;
 }
 
 CFX_ByteString CPWL_FontMap::GetPDFFontAlias(int32_t nFontIndex) {
@@ -208,7 +208,7 @@ int32_t CPWL_FontMap::GetFontIndex(const CFX_ByteString& sFontName,
     return nFontIndex;
 
   CFX_ByteString sAlias;
-  CPDF_Font* pFont = NULL;
+  CPDF_Font* pFont = nullptr;
   if (bFind)
     pFont = FindFontSameCharset(sAlias, nCharset);
 
@@ -246,7 +246,7 @@ int32_t CPWL_FontMap::GetPWLFontIndex(uint16_t word, int32_t nCharset) {
 
 CPDF_Font* CPWL_FontMap::FindFontSameCharset(CFX_ByteString& sFontAlias,
                                              int32_t nCharset) {
-  return NULL;
+  return nullptr;
 }
 
 int32_t CPWL_FontMap::AddFontData(CPDF_Font* pFont,
@@ -301,12 +301,12 @@ CPDF_Font* CPWL_FontMap::AddFontToDocument(CPDF_Document* pDoc,
 CPDF_Font* CPWL_FontMap::AddStandardFont(CPDF_Document* pDoc,
                                          CFX_ByteString& sFontName) {
   if (!pDoc)
-    return NULL;
+    return nullptr;
 
-  CPDF_Font* pFont = NULL;
+  CPDF_Font* pFont = nullptr;
 
   if (sFontName == "ZapfDingbats") {
-    pFont = pDoc->AddStandardFont(sFontName.c_str(), NULL);
+    pFont = pDoc->AddStandardFont(sFontName.c_str(), nullptr);
   } else {
     CPDF_FontEncoding fe(PDFFONT_ENCODING_WINANSI);
     pFont = pDoc->AddStandardFont(sFontName.c_str(), &fe);
@@ -319,7 +319,7 @@ CPDF_Font* CPWL_FontMap::AddSystemFont(CPDF_Document* pDoc,
                                        CFX_ByteString& sFontName,
                                        uint8_t nCharset) {
   if (!pDoc)
-    return NULL;
+    return nullptr;
 
   if (sFontName.IsEmpty())
     sFontName = GetNativeFont(nCharset);
@@ -330,7 +330,7 @@ CPDF_Font* CPWL_FontMap::AddSystemFont(CPDF_Document* pDoc,
     return m_pSystemHandler->AddNativeTrueTypeFontToPDF(pDoc, sFontName,
                                                         nCharset);
 
-  return NULL;
+  return nullptr;
 }
 
 CFX_ByteString CPWL_FontMap::EncodeFontAlias(const CFX_ByteString& sFontName,
@@ -355,7 +355,7 @@ const CPWL_FontMap_Data* CPWL_FontMap::GetFontMapData(int32_t nIndex) const {
     return m_aData.GetAt(nIndex);
   }
 
-  return NULL;
+  return nullptr;
 }
 
 int32_t CPWL_FontMap::GetNativeCharset() {
@@ -424,7 +424,7 @@ const CPWL_FontMap::CharsetFontMap CPWL_FontMap::defaultTTFMap[] = {
 #else
     {EASTEUROPE_CHARSET, "Tahoma"},
 #endif
-    {ARABIC_CHARSET, "Arial"},        {-1, NULL}};
+    {ARABIC_CHARSET, "Arial"},        {-1, nullptr}};
 
 CFX_ByteString CPWL_FontMap::GetDefaultFontByCharset(int32_t nCharset) {
   int i = 0;
diff --git a/fpdfsdk/pdfwindow/PWL_Icon.cpp b/fpdfsdk/pdfwindow/PWL_Icon.cpp
index 18111ac358..9c2e5cbf69 100644
--- a/fpdfsdk/pdfwindow/PWL_Icon.cpp
+++ b/fpdfsdk/pdfwindow/PWL_Icon.cpp
@@ -11,7 +11,7 @@
 #include "fpdfsdk/pdfwindow/PWL_Utils.h"
 #include "fpdfsdk/pdfwindow/PWL_Wnd.h"
 
-CPWL_Image::CPWL_Image() : m_pPDFStream(NULL) {}
+CPWL_Image::CPWL_Image() : m_pPDFStream(nullptr) {}
 
 CPWL_Image::~CPWL_Image() {}
 
@@ -108,7 +108,7 @@ void CPWL_Image::GetImageOffset(FX_FLOAT& x, FX_FLOAT& y) {
   y = 0.0f;
 }
 
-CPWL_Icon::CPWL_Icon() : m_pIconFit(NULL) {}
+CPWL_Icon::CPWL_Icon() : m_pIconFit(nullptr) {}
 
 CPWL_Icon::~CPWL_Icon() {}
 
@@ -130,8 +130,9 @@ void CPWL_Icon::GetIconPosition(FX_FLOAT& fLeft, FX_FLOAT& fBottom) {
   if (m_pIconFit) {
     fLeft = 0.0f;
     fBottom = 0.0f;
-    CPDF_Array* pA =
-        m_pIconFit->GetDict() ? m_pIconFit->GetDict()->GetArrayBy("A") : NULL;
+    CPDF_Array* pA = m_pIconFit->GetDict()
+                         ? m_pIconFit->GetDict()->GetArrayBy("A")
+                         : nullptr;
     if (pA) {
       size_t dwCount = pA->GetCount();
       if (dwCount > 0)
diff --git a/fpdfsdk/pdfwindow/PWL_IconList.cpp b/fpdfsdk/pdfwindow/PWL_IconList.cpp
index 4928560f1c..26d6c92ea4 100644
--- a/fpdfsdk/pdfwindow/PWL_IconList.cpp
+++ b/fpdfsdk/pdfwindow/PWL_IconList.cpp
@@ -19,7 +19,10 @@
 #define PWL_IconList_ITEM_SPACE 4.0f
 
 CPWL_IconList_Item::CPWL_IconList_Item()
-    : m_nIconIndex(-1), m_pData(NULL), m_bSelected(FALSE), m_pText(NULL) {}
+    : m_nIconIndex(-1),
+      m_pData(nullptr),
+      m_bSelected(FALSE),
+      m_pText(nullptr) {}
 
 CPWL_IconList_Item::~CPWL_IconList_Item() {}
 
@@ -288,7 +291,7 @@ CPWL_IconList_Item* CPWL_IconList_Content::GetListItem(
     }
   }
 
-  return NULL;
+  return nullptr;
 }
 
 void CPWL_IconList_Content::SetListData(int32_t nItemIndex, void* pData) {
@@ -328,7 +331,7 @@ void CPWL_IconList_Content::SetIconFillColor(const CPWL_Color& color) {
 }
 
 CPWL_IconList::CPWL_IconList(int32_t nListCount)
-    : m_pListContent(NULL), m_nListCount(nListCount) {}
+    : m_pListContent(nullptr), m_nListCount(nListCount) {}
 
 CPWL_IconList::~CPWL_IconList() {}
 
@@ -392,7 +395,7 @@ void CPWL_IconList::OnNotify(CPWL_Wnd* pWnd,
           m_pListContent->SetScrollPos(
               CFX_FloatPoint(0.0f, *(FX_FLOAT*)lParam));
           m_pListContent->ResetFace();
-          m_pListContent->InvalidateRect(NULL);
+          m_pListContent->InvalidateRect(nullptr);
         }
         return;
       case PNM_SETSCROLLPOS:
@@ -461,7 +464,7 @@ FX_BOOL CPWL_IconList::OnMouseWheel(short zDelta,
     if (ptNew.y != ptScroll.y) {
       m_pListContent->SetScrollPos(ptNew);
       m_pListContent->ResetFace();
-      m_pListContent->InvalidateRect(NULL);
+      m_pListContent->InvalidateRect(nullptr);
 
       if (CPWL_ScrollBar* pScrollBar = GetVScrollBar())
         pScrollBar->OnNotify(this, PNM_SETSCROLLPOS, SBT_VSCROLL,
diff --git a/fpdfsdk/pdfwindow/PWL_Label.cpp b/fpdfsdk/pdfwindow/PWL_Label.cpp
index 203ec49e0f..83d299cd34 100644
--- a/fpdfsdk/pdfwindow/PWL_Label.cpp
+++ b/fpdfsdk/pdfwindow/PWL_Label.cpp
@@ -87,7 +87,7 @@ void CPWL_Label::DrawThisAppearance(CFX_RenderDevice* pDevice,
 
   CFX_FloatRect rcClip;
   CPVT_WordRange wrRange = m_pEdit->GetVisibleWordRange();
-  CPVT_WordRange* pRange = NULL;
+  CPVT_WordRange* pRange = nullptr;
 
   if (!HasFlag(PES_TEXTOVERFLOW)) {
     rcClip = GetClientRect();
@@ -98,7 +98,7 @@ void CPWL_Label::DrawThisAppearance(CFX_RenderDevice* pDevice,
       pDevice, pUser2Device, m_pEdit,
       CPWL_Utils::PWLColorToFXColor(GetTextColor(), GetTransparency()),
       CPWL_Utils::PWLColorToFXColor(GetTextStrokeColor(), GetTransparency()),
-      rcClip, CFX_FloatPoint(0.0f, 0.0f), pRange, pSysHandler, NULL);
+      rcClip, CFX_FloatPoint(0.0f, 0.0f), pRange, pSysHandler, nullptr);
 }
 
 void CPWL_Label::SetHorzScale(int32_t nHorzScale) {
diff --git a/fpdfsdk/pdfwindow/PWL_ListBox.cpp b/fpdfsdk/pdfwindow/PWL_ListBox.cpp
index 86f3b8f24a..84d2614804 100644
--- a/fpdfsdk/pdfwindow/PWL_ListBox.cpp
+++ b/fpdfsdk/pdfwindow/PWL_ListBox.cpp
@@ -65,18 +65,18 @@ void CPWL_List_Notify::IOnInvalidateRect(CFX_FloatRect* pRect) {
 }
 
 CPWL_ListBox::CPWL_ListBox()
-    : m_pList(NULL),
-      m_pListNotify(NULL),
+    : m_pList(nullptr),
+      m_pListNotify(nullptr),
       m_bMouseDown(FALSE),
       m_bHoverSel(FALSE),
-      m_pFillerNotify(NULL) {
+      m_pFillerNotify(nullptr) {
   m_pList = IFX_List::NewList();
 }
 
 CPWL_ListBox::~CPWL_ListBox() {
   IFX_List::DelList(m_pList);
   delete m_pListNotify;
-  m_pListNotify = NULL;
+  m_pListNotify = nullptr;
 }
 
 CFX_ByteString CPWL_ListBox::GetClassName() const {
@@ -100,7 +100,7 @@ void CPWL_ListBox::OnCreated() {
 
 void CPWL_ListBox::OnDestroy() {
   delete m_pListNotify;
-  m_pListNotify = NULL;
+  m_pListNotify = nullptr;
 }
 
 void CPWL_ListBox::GetThisAppearanceStream(CFX_ByteTextBuf& sAppStream) {
@@ -187,21 +187,21 @@ void CPWL_ListBox::DrawThisAppearance(CFX_RenderDevice* pDevice,
               pDevice, pUser2Device, m_pList->GetItemEdit(i),
               CPWL_Utils::PWLColorToFXColor(GetTextColor()),
               CPWL_Utils::PWLColorToFXColor(GetTextStrokeColor()), rcList,
-              ptOffset, NULL, pSysHandler, m_pFormFiller);
+              ptOffset, nullptr, pSysHandler, m_pFormFiller);
           pSysHandler->OutputSelectedRect(m_pFormFiller, rcItem);
         } else {
           CPWL_Utils::DrawFillRect(pDevice, pUser2Device, rcItem,
                                    ArgbEncode(255, 0, 51, 113));
           IFX_Edit::DrawEdit(pDevice, pUser2Device, m_pList->GetItemEdit(i),
                              ArgbEncode(255, 255, 255, 255), 0, rcList,
-                             ptOffset, NULL, pSysHandler, m_pFormFiller);
+                             ptOffset, nullptr, pSysHandler, m_pFormFiller);
         }
       } else {
         CFX_SystemHandler* pSysHandler = GetSystemHandler();
         IFX_Edit::DrawEdit(pDevice, pUser2Device, m_pList->GetItemEdit(i),
                            CPWL_Utils::PWLColorToFXColor(GetTextColor()),
                            CPWL_Utils::PWLColorToFXColor(GetTextStrokeColor()),
-                           rcList, ptOffset, NULL, pSysHandler, NULL);
+                           rcList, ptOffset, nullptr, pSysHandler, nullptr);
       }
     }
   }
diff --git a/fpdfsdk/pdfwindow/PWL_ScrollBar.cpp b/fpdfsdk/pdfwindow/PWL_ScrollBar.cpp
index 9532244bc9..7cec290a6b 100644
--- a/fpdfsdk/pdfwindow/PWL_ScrollBar.cpp
+++ b/fpdfsdk/pdfwindow/PWL_ScrollBar.cpp
@@ -273,7 +273,7 @@ void CPWL_SBButton::DrawThisAppearance(CFX_RenderDevice* pDevice,
             path.SetPoint(2, pt3.x, pt3.y, FXPT_LINETO);
             path.SetPoint(3, pt1.x, pt1.y, FXPT_LINETO);
 
-            pDevice->DrawPath(&path, pUser2Device, NULL,
+            pDevice->DrawPath(&path, pUser2Device, nullptr,
                               CPWL_Utils::PWLColorToFXColor(
                                   PWL_DEFAULT_BLACKCOLOR, nTransparancy),
                               0, FXFILL_ALTERNATE);
@@ -297,7 +297,7 @@ void CPWL_SBButton::DrawThisAppearance(CFX_RenderDevice* pDevice,
             path.SetPoint(2, pt3.x, pt3.y, FXPT_LINETO);
             path.SetPoint(3, pt1.x, pt1.y, FXPT_LINETO);
 
-            pDevice->DrawPath(&path, pUser2Device, NULL,
+            pDevice->DrawPath(&path, pUser2Device, nullptr,
                               CPWL_Utils::PWLColorToFXColor(
                                   PWL_DEFAULT_BLACKCOLOR, nTransparancy),
                               0, FXFILL_ALTERNATE);
@@ -579,9 +579,9 @@ FX_BOOL CPWL_SBButton::OnMouseMove(const CFX_FloatPoint& point,
 
 CPWL_ScrollBar::CPWL_ScrollBar(PWL_SCROLLBAR_TYPE sbType)
     : m_sbType(sbType),
-      m_pMinButton(NULL),
-      m_pMaxButton(NULL),
-      m_pPosButton(NULL),
+      m_pMinButton(nullptr),
+      m_pMaxButton(nullptr),
+      m_pPosButton(nullptr),
       m_bMouseDown(FALSE),
       m_bMinOrMax(FALSE),
       m_bNotifyForever(TRUE) {}
diff --git a/fpdfsdk/pdfwindow/PWL_Signature.cpp b/fpdfsdk/pdfwindow/PWL_Signature.cpp
index c737998f26..7513950cb7 100644
--- a/fpdfsdk/pdfwindow/PWL_Signature.cpp
+++ b/fpdfsdk/pdfwindow/PWL_Signature.cpp
@@ -12,7 +12,7 @@
 #include "fpdfsdk/pdfwindow/PWL_Utils.h"
 #include "fpdfsdk/pdfwindow/PWL_Wnd.h"
 
-CPWL_Signature_Image::CPWL_Signature_Image() : m_pImage(NULL) {}
+CPWL_Signature_Image::CPWL_Signature_Image() : m_pImage(nullptr) {}
 
 CPWL_Signature_Image::~CPWL_Signature_Image() {}
 
@@ -57,9 +57,9 @@ void CPWL_Signature_Image::GetScale(FX_FLOAT& fHScale, FX_FLOAT& fVScale) {
 }
 
 CPWL_Signature::CPWL_Signature()
-    : m_pText(NULL),
-      m_pDescription(NULL),
-      m_pImage(NULL),
+    : m_pText(nullptr),
+      m_pDescription(nullptr),
+      m_pImage(nullptr),
       m_bTextExist(TRUE),
       m_bImageExist(FALSE),
       m_bFlagExist(TRUE) {}
diff --git a/fpdfsdk/pdfwindow/PWL_Utils.cpp b/fpdfsdk/pdfwindow/PWL_Utils.cpp
index e4232db5e8..f5d30b2d14 100644
--- a/fpdfsdk/pdfwindow/PWL_Utils.cpp
+++ b/fpdfsdk/pdfwindow/PWL_Utils.cpp
@@ -1222,7 +1222,7 @@ void CPWL_Utils::DrawFillRect(CFX_RenderDevice* pDevice,
   CFX_PathData path;
   CFX_FloatRect rcTemp(rect);
   path.AppendRect(rcTemp.left, rcTemp.bottom, rcTemp.right, rcTemp.top);
-  pDevice->DrawPath(&path, pUser2Device, NULL, color, 0, FXFILL_WINDING);
+  pDevice->DrawPath(&path, pUser2Device, nullptr, color, 0, FXFILL_WINDING);
 }
 
 void CPWL_Utils::DrawFillArea(CFX_RenderDevice* pDevice,
@@ -1237,7 +1237,7 @@ void CPWL_Utils::DrawFillArea(CFX_RenderDevice* pDevice,
   for (int32_t i = 1; i < nCount; i++)
     path.SetPoint(i, pPts[i].x, pPts[i].y, FXPT_LINETO);
 
-  pDevice->DrawPath(&path, pUser2Device, NULL, color, 0, FXFILL_ALTERNATE);
+  pDevice->DrawPath(&path, pUser2Device, nullptr, color, 0, FXFILL_ALTERNATE);
 }
 
 void CPWL_Utils::DrawStrokeRect(CFX_RenderDevice* pDevice,
@@ -1340,7 +1340,7 @@ void CPWL_Utils::DrawBorder(CFX_RenderDevice* pDevice,
         path.AppendRect(fLeft, fBottom, fRight, fTop);
         path.AppendRect(fLeft + fWidth, fBottom + fWidth, fRight - fWidth,
                         fTop - fWidth);
-        pDevice->DrawPath(&path, pUser2Device, NULL,
+        pDevice->DrawPath(&path, pUser2Device, nullptr,
                           PWLColorToFXColor(color, nTransparancy), 0,
                           FXFILL_ALTERNATE);
         break;
diff --git a/fpdfsdk/pdfwindow/PWL_Utils.h b/fpdfsdk/pdfwindow/PWL_Utils.h
index 8ab08a857e..db79cf77e2 100644
--- a/fpdfsdk/pdfwindow/PWL_Utils.h
+++ b/fpdfsdk/pdfwindow/PWL_Utils.h
@@ -168,13 +168,13 @@ class CPWL_Utils {
 
   static CFX_ByteString GetEditAppStream(IFX_Edit* pEdit,
                                          const CFX_FloatPoint& ptOffset,
-                                         const CPVT_WordRange* pRange = NULL,
+                                         const CPVT_WordRange* pRange = nullptr,
                                          FX_BOOL bContinuous = TRUE,
                                          uint16_t SubWord = 0);
   static CFX_ByteString GetEditSelAppStream(
       IFX_Edit* pEdit,
       const CFX_FloatPoint& ptOffset,
-      const CPVT_WordRange* pRange = NULL);
+      const CPVT_WordRange* pRange = nullptr);
   static CFX_ByteString GetTextAppStream(const CFX_FloatRect& rcBBox,
                                          IPVT_FontMap* pFontMap,
                                          const CFX_WideString& sText,
diff --git a/fpdfsdk/pdfwindow/PWL_Wnd.cpp b/fpdfsdk/pdfwindow/PWL_Wnd.cpp
index 310f2f3f90..2a0a0aabbb 100644
--- a/fpdfsdk/pdfwindow/PWL_Wnd.cpp
+++ b/fpdfsdk/pdfwindow/PWL_Wnd.cpp
@@ -55,7 +55,7 @@ void CPWL_Timer::TimerProc(int32_t idEvent) {
     pTimer->m_pAttached->TimerProc();
 }
 
-CPWL_TimerHandler::CPWL_TimerHandler() : m_pTimer(NULL) {}
+CPWL_TimerHandler::CPWL_TimerHandler() : m_pTimer(nullptr) {}
 
 CPWL_TimerHandler::~CPWL_TimerHandler() {
   delete m_pTimer;
@@ -90,8 +90,8 @@ class CPWL_MsgControl {
   void Default() {
     m_aMousePath.RemoveAll();
     m_aKeyboardPath.RemoveAll();
-    m_pMainMouseWnd = NULL;
-    m_pMainKeyboardWnd = NULL;
+    m_pMainMouseWnd = nullptr;
+    m_pMainKeyboardWnd = nullptr;
   }
 
   FX_BOOL IsWndCreated(const CPWL_Wnd* pWnd) const {
@@ -149,7 +149,7 @@ class CPWL_MsgControl {
       if (CPWL_Wnd* pWnd = m_aKeyboardPath.GetAt(0))
         pWnd->OnKillFocus();
 
-    m_pMainKeyboardWnd = NULL;
+    m_pMainKeyboardWnd = nullptr;
     m_aKeyboardPath.RemoveAll();
   }
 
@@ -168,7 +168,7 @@ class CPWL_MsgControl {
   }
 
   void ReleaseCapture() {
-    m_pMainMouseWnd = NULL;
+    m_pMainMouseWnd = nullptr;
     m_aMousePath.RemoveAll();
   }
 
@@ -181,7 +181,7 @@ class CPWL_MsgControl {
 };
 
 CPWL_Wnd::CPWL_Wnd()
-    : m_pVScrollBar(NULL),
+    : m_pVScrollBar(nullptr),
       m_rcWindow(),
       m_rcClip(),
       m_bCreated(FALSE),
@@ -255,7 +255,7 @@ void CPWL_Wnd::Destroy() {
       if (CPWL_Wnd* pChild = m_aChildren[i]) {
         pChild->Destroy();
         delete pChild;
-        pChild = NULL;
+        pChild = nullptr;
       }
     }
 
@@ -268,7 +268,7 @@ void CPWL_Wnd::Destroy() {
 
   FXSYS_memset(&m_sPrivateParam, 0, sizeof(PWL_CREATEPARAM));
   m_aChildren.RemoveAll();
-  m_pVScrollBar = NULL;
+  m_pVScrollBar = nullptr;
 }
 
 void CPWL_Wnd::Move(const CFX_FloatRect& rcNew,
@@ -624,7 +624,7 @@ CPWL_ScrollBar* CPWL_Wnd::GetVScrollBar() const {
   if (HasFlag(PWS_VSCROLL))
     return m_pVScrollBar;
 
-  return NULL;
+  return nullptr;
 }
 
 void CPWL_Wnd::CreateScrollBar(const PWL_CREATEPARAM& cp) {
@@ -958,7 +958,7 @@ const CPWL_Wnd* CPWL_Wnd::GetFocused() const {
     return pMsgCtrl->m_pMainKeyboardWnd;
   }
 
-  return NULL;
+  return nullptr;
 }
 
 void CPWL_Wnd::EnableWindow(FX_BOOL bEnable) {
diff --git a/fpdfsdk/pdfwindow/PWL_Wnd.h b/fpdfsdk/pdfwindow/PWL_Wnd.h
index c8552fb985..c393d2730e 100644
--- a/fpdfsdk/pdfwindow/PWL_Wnd.h
+++ b/fpdfsdk/pdfwindow/PWL_Wnd.h
@@ -188,13 +188,13 @@ struct PWL_CREATEPARAM {
  public:
   PWL_CREATEPARAM()
       : rcRectWnd(0, 0, 0, 0),
-        pSystemHandler(NULL),
-        pFontMap(NULL),
-        pProvider(NULL),
-        pFocusHandler(NULL),
+        pSystemHandler(nullptr),
+        pFontMap(nullptr),
+        pProvider(nullptr),
+        pFocusHandler(nullptr),
         dwFlags(0),
         sBackgroundColor(),
-        hAttachedWnd(NULL),
+        hAttachedWnd(nullptr),
         nBorderStyle(BorderStyle::SOLID),
         dwBorderWidth(1),
         sBorderColor(),
@@ -203,9 +203,9 @@ struct PWL_CREATEPARAM {
         nTransparency(255),
         fFontSize(PWL_DEFAULT_FONTSIZE),
         sDash(3, 0, 0),
-        pAttachedData(NULL),
-        pParentWnd(NULL),
-        pMsgControl(NULL),
+        pAttachedData(nullptr),
+        pParentWnd(nullptr),
+        pMsgControl(nullptr),
         eCursorType(FXCT_ARROW),
         mtChild(1, 0, 0, 1, 0, 0) {}
 
@@ -274,7 +274,7 @@ class CPWL_Wnd : public CPWL_TimerHandler {
   void InvalidateProvider(IPWL_Provider* provider);
   void Destroy();
   void Move(const CFX_FloatRect& rcNew, FX_BOOL bReset, FX_BOOL bRefresh);
-  virtual void InvalidateRect(CFX_FloatRect* pRect = NULL);
+  virtual void InvalidateRect(CFX_FloatRect* pRect = nullptr);
 
   void DrawAppearance(CFX_RenderDevice* pDevice, CFX_Matrix* pUser2Device);