Remove some c_str() calls from StringCs in xfa docs.

Avoids the risk of possibly getting a non-null terminated
buffer if the StringC happened to be created by Mid(), etc.
Doesn't seem to happen in practice.

Review-Url: https://codereview.chromium.org/1983683003

12 files changed, 117 insertions, 128 deletions

diff --git a/fpdfsdk/fpdfxfa/fpdfxfa_app.cpp b/fpdfsdk/fpdfxfa/fpdfxfa_app.cpp
index f9c3ca65a3..e91bdf1699 100644
--- a/fpdfsdk/fpdfxfa/fpdfxfa_app.cpp
+++ b/fpdfsdk/fpdfxfa/fpdfxfa_app.cpp
@@ -131,8 +131,8 @@ void CPDFXFA_App::Beep(uint32_t dwType) {
   }
 }
 
-int32_t CPDFXFA_App::MsgBox(const CFX_WideStringC& wsMessage,
-                            const CFX_WideStringC& wsTitle,
+int32_t CPDFXFA_App::MsgBox(const CFX_WideString& wsMessage,
+                            const CFX_WideString& wsTitle,
                             uint32_t dwIconType,
                             uint32_t dwButtonType) {
   CPDFDoc_Environment* pEnv = m_pEnvList.GetAt(0);
@@ -184,11 +184,11 @@ int32_t CPDFXFA_App::MsgBox(const CFX_WideStringC& wsMessage,
   return XFA_IDYes;
 }
 
-void CPDFXFA_App::Response(CFX_WideString& wsAnswer,
-                           const CFX_WideStringC& wsQuestion,
-                           const CFX_WideStringC& wsTitle,
-                           const CFX_WideStringC& wsDefaultAnswer,
-                           FX_BOOL bMark) {
+CFX_WideString CPDFXFA_App::Response(const CFX_WideString& wsQuestion,
+                                     const CFX_WideString& wsTitle,
+                                     const CFX_WideString& wsDefaultAnswer,
+                                     FX_BOOL bMark) {
+  CFX_WideString wsAnswer;
   CPDFDoc_Environment* pEnv = m_pEnvList.GetAt(0);
   if (pEnv) {
     int nLength = 2048;
@@ -206,6 +206,7 @@ void CPDFXFA_App::Response(CFX_WideString& wsAnswer,
     }
     delete[] pBuff;
   }
+  return wsAnswer;
 }
 
 int32_t CPDFXFA_App::GetCurDocumentInBatch() {
@@ -225,39 +226,34 @@ int32_t CPDFXFA_App::GetDocumentCountInBatch() {
   return 0;
 }
 
-IFX_FileRead* CPDFXFA_App::DownloadURL(const CFX_WideStringC& wsURL) {
+IFX_FileRead* CPDFXFA_App::DownloadURL(const CFX_WideString& wsURL) {
   CPDFDoc_Environment* pEnv = m_pEnvList.GetAt(0);
-  if (pEnv) {
-    return pEnv->FFI_DownloadFromURL(wsURL.c_str());
-  }
-  return NULL;
+  return pEnv ? pEnv->FFI_DownloadFromURL(wsURL.c_str()) : nullptr;
 }
 
-FX_BOOL CPDFXFA_App::PostRequestURL(const CFX_WideStringC& wsURL,
-                                    const CFX_WideStringC& wsData,
-                                    const CFX_WideStringC& wsContentType,
-                                    const CFX_WideStringC& wsEncode,
-                                    const CFX_WideStringC& wsHeader,
+FX_BOOL CPDFXFA_App::PostRequestURL(const CFX_WideString& wsURL,
+                                    const CFX_WideString& wsData,
+                                    const CFX_WideString& wsContentType,
+                                    const CFX_WideString& wsEncode,
+                                    const CFX_WideString& wsHeader,
                                     CFX_WideString& wsResponse) {
   CPDFDoc_Environment* pEnv = m_pEnvList.GetAt(0);
-  if (pEnv) {
-    wsResponse = pEnv->FFI_PostRequestURL(wsURL.c_str(), wsData.c_str(),
-                                          wsContentType.c_str(),
-                                          wsEncode.c_str(), wsHeader.c_str());
-    return TRUE;
-  }
-  return FALSE;
+  if (!pEnv)
+    return FALSE;
+
+  wsResponse = pEnv->FFI_PostRequestURL(wsURL.c_str(), wsData.c_str(),
+                                        wsContentType.c_str(), wsEncode.c_str(),
+                                        wsHeader.c_str());
+  return TRUE;
 }
 
-FX_BOOL CPDFXFA_App::PutRequestURL(const CFX_WideStringC& wsURL,
-                                   const CFX_WideStringC& wsData,
-                                   const CFX_WideStringC& wsEncode) {
+FX_BOOL CPDFXFA_App::PutRequestURL(const CFX_WideString& wsURL,
+                                   const CFX_WideString& wsData,
+                                   const CFX_WideString& wsEncode) {
   CPDFDoc_Environment* pEnv = m_pEnvList.GetAt(0);
-  if (pEnv) {
-    return pEnv->FFI_PutRequestURL(wsURL.c_str(), wsData.c_str(),
-                                   wsEncode.c_str());
-  }
-  return FALSE;
+  return pEnv &&
+         pEnv->FFI_PutRequestURL(wsURL.c_str(), wsData.c_str(),
+                                 wsEncode.c_str());
 }
 
 void CPDFXFA_App::LoadString(int32_t iStringID, CFX_WideString& wsString) {
diff --git a/fpdfsdk/fpdfxfa/fpdfxfa_doc.cpp b/fpdfsdk/fpdfxfa/fpdfxfa_doc.cpp
index deba943072..b2f752e8b9 100644
--- a/fpdfsdk/fpdfxfa/fpdfxfa_doc.cpp
+++ b/fpdfsdk/fpdfxfa/fpdfxfa_doc.cpp
@@ -625,21 +625,22 @@ void CPDFXFA_Document::SetTitle(CXFA_FFDoc* hDoc,
 }
 
 void CPDFXFA_Document::ExportData(CXFA_FFDoc* hDoc,
-                                  const CFX_WideStringC& wsFilePath,
+                                  const CFX_WideString& wsFilePath,
                                   FX_BOOL bXDP) {
   if (hDoc != m_pXFADoc)
     return;
+
   if (m_iDocType != DOCTYPE_DYNAMIC_XFA && m_iDocType != DOCTYPE_STATIC_XFA)
     return;
+
   CPDFDoc_Environment* pEnv = m_pSDKDoc->GetEnv();
-  if (pEnv == NULL)
+  if (!pEnv)
     return;
-  int fileType = bXDP ? FXFA_SAVEAS_XDP : FXFA_SAVEAS_XML;
-  CFX_ByteString bs = CFX_WideString(wsFilePath).UTF16LE_Encode();
 
+  int fileType = bXDP ? FXFA_SAVEAS_XDP : FXFA_SAVEAS_XML;
+  CFX_ByteString bs = wsFilePath.UTF16LE_Encode();
   if (wsFilePath.IsEmpty()) {
-    if (!pEnv->GetFormFillInfo() ||
-        pEnv->GetFormFillInfo()->m_pJsPlatform == NULL)
+    if (!pEnv->GetFormFillInfo() || !pEnv->GetFormFillInfo()->m_pJsPlatform)
       return;
     CFX_WideString filepath = pEnv->JS_fieldBrowse();
     bs = filepath.UTF16LE_Encode();
@@ -649,12 +650,10 @@ void CPDFXFA_Document::ExportData(CXFA_FFDoc* hDoc,
       bXDP ? FXFA_SAVEAS_XDP : FXFA_SAVEAS_XML,
       (FPDF_WIDESTRING)bs.GetBuffer(len * sizeof(unsigned short)), "wb");
   bs.ReleaseBuffer(len * sizeof(unsigned short));
-
-  if (pFileHandler == NULL)
+  if (!pFileHandler)
     return;
 
   CFPDF_FileStream fileWrite(pFileHandler);
-
   CFX_ByteString content;
   if (fileType == FXFA_SAVEAS_XML) {
     content = "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\r\n";
@@ -725,10 +724,10 @@ void CPDFXFA_Document::ExportData(CXFA_FFDoc* hDoc,
   }
 }
 void CPDFXFA_Document::ImportData(CXFA_FFDoc* hDoc,
-                                  const CFX_WideStringC& wsFilePath) {}
+                                  const CFX_WideString& wsFilePath) {}
 
 void CPDFXFA_Document::GotoURL(CXFA_FFDoc* hDoc,
-                               const CFX_WideStringC& bsURL,
+                               const CFX_WideString& bsURL,
                                FX_BOOL bAppend) {
   if (hDoc != m_pXFADoc)
     return;
diff --git a/fpdfsdk/fpdfxfa/include/fpdfxfa_app.h b/fpdfsdk/fpdfxfa/include/fpdfxfa_app.h
index 6491781cbe..3a61ef40c3 100644
--- a/fpdfsdk/fpdfxfa/include/fpdfxfa_app.h
+++ b/fpdfsdk/fpdfxfa/include/fpdfxfa_app.h
@@ -51,29 +51,28 @@ class CPDFXFA_App : public IXFA_AppProvider {
   }
 
   void Beep(uint32_t dwType) override;
-  int32_t MsgBox(const CFX_WideStringC& wsMessage,
-                 const CFX_WideStringC& wsTitle,
+  int32_t MsgBox(const CFX_WideString& wsMessage,
+                 const CFX_WideString& wsTitle,
                  uint32_t dwIconType,
                  uint32_t dwButtonType) override;
-  void Response(CFX_WideString& wsAnswer,
-                const CFX_WideStringC& wsQuestion,
-                const CFX_WideStringC& wsTitle,
-                const CFX_WideStringC& wsDefaultAnswer,
-                FX_BOOL bMark) override;
+  CFX_WideString Response(const CFX_WideString& wsQuestion,
+                          const CFX_WideString& wsTitle,
+                          const CFX_WideString& wsDefaultAnswer,
+                          FX_BOOL bMark) override;
 
   int32_t GetDocumentCountInBatch() override;
   int32_t GetCurDocumentInBatch() override;
 
-  IFX_FileRead* DownloadURL(const CFX_WideStringC& wsURL) override;
-  FX_BOOL PostRequestURL(const CFX_WideStringC& wsURL,
-                         const CFX_WideStringC& wsData,
-                         const CFX_WideStringC& wsContentType,
-                         const CFX_WideStringC& wsEncode,
-                         const CFX_WideStringC& wsHeader,
+  IFX_FileRead* DownloadURL(const CFX_WideString& wsURL) override;
+  FX_BOOL PostRequestURL(const CFX_WideString& wsURL,
+                         const CFX_WideString& wsData,
+                         const CFX_WideString& wsContentType,
+                         const CFX_WideString& wsEncode,
+                         const CFX_WideString& wsHeader,
                          CFX_WideString& wsResponse) override;
-  FX_BOOL PutRequestURL(const CFX_WideStringC& wsURL,
-                        const CFX_WideStringC& wsData,
-                        const CFX_WideStringC& wsEncode) override;
+  FX_BOOL PutRequestURL(const CFX_WideString& wsURL,
+                        const CFX_WideString& wsData,
+                        const CFX_WideString& wsEncode) override;
 
   void LoadString(int32_t iStringID, CFX_WideString& wsString) override;
   IFWL_AdapterTimerMgr* GetTimerMgr() override;
diff --git a/fpdfsdk/fpdfxfa/include/fpdfxfa_doc.h b/fpdfsdk/fpdfxfa/include/fpdfxfa_doc.h
index a67b7803a0..416e4b9de3 100644
--- a/fpdfsdk/fpdfxfa/include/fpdfxfa_doc.h
+++ b/fpdfsdk/fpdfxfa/include/fpdfxfa_doc.h
@@ -92,11 +92,11 @@ class CPDFXFA_Document : public IXFA_DocProvider {
   virtual void GetTitle(CXFA_FFDoc* hDoc, CFX_WideString& wsTitle);
   virtual void SetTitle(CXFA_FFDoc* hDoc, const CFX_WideString& wsTitle);
   virtual void ExportData(CXFA_FFDoc* hDoc,
-                          const CFX_WideStringC& wsFilePath,
+                          const CFX_WideString& wsFilePath,
                           FX_BOOL bXDP = TRUE);
-  virtual void ImportData(CXFA_FFDoc* hDoc, const CFX_WideStringC& wsFilePath);
+  virtual void ImportData(CXFA_FFDoc* hDoc, const CFX_WideString& wsFilePath);
   virtual void GotoURL(CXFA_FFDoc* hDoc,
-                       const CFX_WideStringC& bsURL,
+                       const CFX_WideString& bsURL,
                        FX_BOOL bAppend = TRUE);
   virtual FX_BOOL IsValidationsEnabled(CXFA_FFDoc* hDoc);
   virtual void SetValidationsEnabled(CXFA_FFDoc* hDoc, FX_BOOL bEnabled);
diff --git a/xfa/fxfa/app/xfa_ffdocview.cpp b/xfa/fxfa/app/xfa_ffdocview.cpp
index cd48a43a0e..4a610495dd 100644
--- a/xfa/fxfa/app/xfa_ffdocview.cpp
+++ b/xfa/fxfa/app/xfa_ffdocview.cpp
@@ -162,8 +162,7 @@ void CXFA_FFDocView::ShowNullTestMsg() {
     }
     CFX_WideString wsTitle;
     pAppProvider->LoadString(XFA_IDS_AppName, wsTitle);
-    pAppProvider->MsgBox(wsMsg.AsStringC(), wsTitle.AsStringC(),
-                         XFA_MBICON_Status, XFA_MB_OK);
+    pAppProvider->MsgBox(wsMsg, wsTitle, XFA_MBICON_Status, XFA_MB_OK);
   }
   m_arrNullTestMsg.RemoveAll();
 }
diff --git a/xfa/fxfa/app/xfa_fffield.cpp b/xfa/fxfa/app/xfa_fffield.cpp
index cb65a0b9a9..7cf0c6e3fc 100644
--- a/xfa/fxfa/app/xfa_fffield.cpp
+++ b/xfa/fxfa/app/xfa_fffield.cpp
@@ -725,8 +725,8 @@ int32_t CXFA_FFField::CalculateWidgetAcc(CXFA_WidgetAcc* pAcc) {
           wsMessage += wsWarning;
           CFX_WideString wsTitle;
           pAppProvider->LoadString(XFA_IDS_CalcOverride, wsTitle);
-          pAppProvider->MsgBox(wsMessage.AsStringC(), wsTitle.AsStringC(),
-                               XFA_MBICON_Warning, XFA_MB_OK);
+          pAppProvider->MsgBox(wsMessage, wsTitle, XFA_MBICON_Warning,
+                               XFA_MB_OK);
         }
       }
         return 0;
@@ -757,8 +757,7 @@ int32_t CXFA_FFField::CalculateWidgetAcc(CXFA_WidgetAcc* pAcc) {
           wsMessage += wsWarning;
           CFX_WideString wsTitle;
           pAppProvider->LoadString(XFA_IDS_CalcOverride, wsTitle);
-          if (pAppProvider->MsgBox(wsMessage.AsStringC(), wsTitle.AsStringC(),
-                                   XFA_MBICON_Warning,
+          if (pAppProvider->MsgBox(wsMessage, wsTitle, XFA_MBICON_Warning,
                                    XFA_MB_YesNo) == XFA_IDYes) {
             pAcc->GetNode()->SetFlag(XFA_NODEFLAG_UserInteractive, false);
             return 1;
diff --git a/xfa/fxfa/app/xfa_fftext.cpp b/xfa/fxfa/app/xfa_fftext.cpp
index c5e1cba2a8..1000b91c08 100644
--- a/xfa/fxfa/app/xfa_fftext.cpp
+++ b/xfa/fxfa/app/xfa_fftext.cpp
@@ -136,7 +136,7 @@ FX_BOOL CXFA_FFText::OnLButtonUp(uint32_t dwFlags, FX_FLOAT fx, FX_FLOAT fy) {
     return FALSE;
   }
   CXFA_FFDoc* pDoc = GetDoc();
-  pDoc->GetDocProvider()->GotoURL(pDoc, CFX_WideStringC(wsURLContent), FALSE);
+  pDoc->GetDocProvider()->GotoURL(pDoc, wsURLContent, FALSE);
   return TRUE;
 }
 FWL_WidgetHit CXFA_FFText::OnHitTest(FX_FLOAT fx, FX_FLOAT fy) {
diff --git a/xfa/fxfa/app/xfa_fftextedit.cpp b/xfa/fxfa/app/xfa_fftextedit.cpp
index f5605c9775..ea641f2066 100644
--- a/xfa/fxfa/app/xfa_fftextedit.cpp
+++ b/xfa/fxfa/app/xfa_fftextedit.cpp
@@ -194,14 +194,13 @@ void CXFA_FFTextEdit::ValidateNumberField(const CFX_WideString& wsText) {
     if (pAppProvider) {
       CFX_WideString wsTitle;
       pAppProvider->LoadString(XFA_IDS_AppName, wsTitle);
-      CFX_WideString wsMessage;
       CFX_WideString wsError;
       pAppProvider->LoadString(XFA_IDS_ValidateNumberError, wsError);
       CFX_WideString wsSomField;
       pAcc->GetNode()->GetSOMExpression(wsSomField);
+      CFX_WideString wsMessage;
       wsMessage.Format(wsError.c_str(), wsText.c_str(), wsSomField.c_str());
-      pAppProvider->MsgBox(wsMessage.AsStringC(), wsTitle.AsStringC(),
-                           XFA_MBICON_Error, XFA_MB_OK);
+      pAppProvider->MsgBox(wsMessage, wsTitle, XFA_MBICON_Error, XFA_MB_OK);
     }
   }
 }
diff --git a/xfa/fxfa/app/xfa_ffwidgetacc.cpp b/xfa/fxfa/app/xfa_ffwidgetacc.cpp
index 11081fd5d7..64ac9b2d60 100644
--- a/xfa/fxfa/app/xfa_ffwidgetacc.cpp
+++ b/xfa/fxfa/app/xfa_ffwidgetacc.cpp
@@ -389,12 +389,11 @@ void CXFA_WidgetAcc::ProcessScriptTestValidate(CXFA_Validate validate,
           GetValidateMessage(pAppProvider, wsScriptMsg, FALSE, bVersionFlag);
         }
         if (bVersionFlag) {
-          pAppProvider->MsgBox(wsScriptMsg.AsStringC(), wsTitle.AsStringC(),
-                               XFA_MBICON_Warning, XFA_MB_OK);
+          pAppProvider->MsgBox(wsScriptMsg, wsTitle, XFA_MBICON_Warning,
+                               XFA_MB_OK);
           return;
         }
-        if (pAppProvider->MsgBox(wsScriptMsg.AsStringC(), wsTitle.AsStringC(),
-                                 XFA_MBICON_Warning,
+        if (pAppProvider->MsgBox(wsScriptMsg, wsTitle, XFA_MBICON_Warning,
                                  XFA_MB_YesNo) == XFA_IDYes) {
           GetNode()->SetFlag(XFA_NODEFLAG_UserInteractive, false);
         }
@@ -402,8 +401,7 @@ void CXFA_WidgetAcc::ProcessScriptTestValidate(CXFA_Validate validate,
         if (wsScriptMsg.IsEmpty()) {
           GetValidateMessage(pAppProvider, wsScriptMsg, TRUE, bVersionFlag);
         }
-        pAppProvider->MsgBox(wsScriptMsg.AsStringC(), wsTitle.AsStringC(),
-                             XFA_MBICON_Error, XFA_MB_OK);
+        pAppProvider->MsgBox(wsScriptMsg, wsTitle, XFA_MBICON_Error, XFA_MB_OK);
       }
     }
   }
@@ -436,8 +434,7 @@ int32_t CXFA_WidgetAcc::ProcessFormatTestValidate(CXFA_Validate validate,
         if (wsFormatMsg.IsEmpty()) {
           GetValidateMessage(pAppProvider, wsFormatMsg, TRUE, bVersionFlag);
         }
-        pAppProvider->MsgBox(wsFormatMsg.AsStringC(), wsTitle.AsStringC(),
-                             XFA_MBICON_Error, XFA_MB_OK);
+        pAppProvider->MsgBox(wsFormatMsg, wsTitle, XFA_MBICON_Error, XFA_MB_OK);
         return XFA_EVENTERROR_Success;
       }
       if (GetNode()->HasFlag(XFA_NODEFLAG_UserInteractive)) {
@@ -447,12 +444,12 @@ int32_t CXFA_WidgetAcc::ProcessFormatTestValidate(CXFA_Validate validate,
         GetValidateMessage(pAppProvider, wsFormatMsg, FALSE, bVersionFlag);
       }
       if (bVersionFlag) {
-        pAppProvider->MsgBox(wsFormatMsg.AsStringC(), wsTitle.AsStringC(),
-                             XFA_MBICON_Warning, XFA_MB_OK);
+        pAppProvider->MsgBox(wsFormatMsg, wsTitle, XFA_MBICON_Warning,
+                             XFA_MB_OK);
         return XFA_EVENTERROR_Success;
       }
-      if (pAppProvider->MsgBox(wsFormatMsg.AsStringC(), wsTitle.AsStringC(),
-                               XFA_MBICON_Warning, XFA_MB_YesNo) == XFA_IDYes) {
+      if (pAppProvider->MsgBox(wsFormatMsg, wsTitle, XFA_MBICON_Warning,
+                               XFA_MB_YesNo) == XFA_IDYes) {
         GetNode()->SetFlag(XFA_NODEFLAG_UserInteractive, false);
       }
       return XFA_EVENTERROR_Success;
@@ -507,8 +504,7 @@ int32_t CXFA_WidgetAcc::ProcessNullTestValidate(CXFA_Validate validate,
         pAppProvider->LoadString(XFA_IDS_ValidateNullError, wsError);
         wsNullMsg.Format(wsError.c_str(), wsCaptionName.c_str());
       }
-      pAppProvider->MsgBox(wsNullMsg.AsStringC(), wsTitle.AsStringC(),
-                           XFA_MBICON_Status, XFA_MB_OK);
+      pAppProvider->MsgBox(wsNullMsg, wsTitle, XFA_MBICON_Status, XFA_MB_OK);
       return XFA_EVENTERROR_Error;
     }
     case XFA_ATTRIBUTEENUM_Warning: {
@@ -522,8 +518,8 @@ int32_t CXFA_WidgetAcc::ProcessNullTestValidate(CXFA_Validate validate,
         wsNullMsg.Format(wsWarning.c_str(), wsCaptionName.c_str(),
                          wsCaptionName.c_str());
       }
-      if (pAppProvider->MsgBox(wsNullMsg.AsStringC(), wsTitle.AsStringC(),
-                               XFA_MBICON_Warning, XFA_MB_YesNo) == XFA_IDYes) {
+      if (pAppProvider->MsgBox(wsNullMsg, wsTitle, XFA_MBICON_Warning,
+                               XFA_MB_YesNo) == XFA_IDYes) {
         GetNode()->SetFlag(XFA_NODEFLAG_UserInteractive, false);
       }
       return XFA_EVENTERROR_Error;
diff --git a/xfa/fxfa/fm2js/xfa_fm2jscontext.cpp b/xfa/fxfa/fm2js/xfa_fm2jscontext.cpp
index 484191f1be..e47d0af390 100644
--- a/xfa/fxfa/fm2js/xfa_fm2jscontext.cpp
+++ b/xfa/fxfa/fm2js/xfa_fm2jscontext.cpp
@@ -5440,7 +5440,7 @@ void CXFA_FM2JSContext::Get(FXJSE_HOBJECT hThis,
     CFX_ByteString urlString;
     HValueToUTF8String(argOne, urlString);
     IFX_FileRead* pFile = pAppProvider->DownloadURL(
-        CFX_WideString::FromUTF8(urlString.AsStringC()).AsStringC());
+        CFX_WideString::FromUTF8(urlString.AsStringC()));
     if (pFile) {
       int32_t size = pFile->GetSize();
       uint8_t* pData = FX_Alloc(uint8_t, size);
@@ -5500,12 +5500,11 @@ void CXFA_FM2JSContext::Post(FXJSE_HOBJECT hThis,
     }
     CFX_WideString decodedResponse;
     FX_BOOL bFlags = pAppProvider->PostRequestURL(
-        CFX_WideString::FromUTF8(bsURL.AsStringC()).AsStringC(),
-        CFX_WideString::FromUTF8(bsData.AsStringC()).AsStringC(),
-        CFX_WideString::FromUTF8(bsContentType.AsStringC()).AsStringC(),
-        CFX_WideString::FromUTF8(bsEncode.AsStringC()).AsStringC(),
-        CFX_WideString::FromUTF8(bsHeader.AsStringC()).AsStringC(),
-        decodedResponse);
+        CFX_WideString::FromUTF8(bsURL.AsStringC()),
+        CFX_WideString::FromUTF8(bsData.AsStringC()),
+        CFX_WideString::FromUTF8(bsContentType.AsStringC()),
+        CFX_WideString::FromUTF8(bsEncode.AsStringC()),
+        CFX_WideString::FromUTF8(bsHeader.AsStringC()), decodedResponse);
     FXJSE_Value_Release(argOne);
     FXJSE_Value_Release(argTwo);
     if (argc > 2) {
@@ -5561,9 +5560,9 @@ void CXFA_FM2JSContext::Put(FXJSE_HOBJECT hThis,
       HValueToUTF8String(argThree, bsEncode);
     }
     FX_BOOL bFlags = pAppProvider->PutRequestURL(
-        CFX_WideString::FromUTF8(bsURL.AsStringC()).AsStringC(),
-        CFX_WideString::FromUTF8(bsData.AsStringC()).AsStringC(),
-        CFX_WideString::FromUTF8(bsEncode.AsStringC()).AsStringC());
+        CFX_WideString::FromUTF8(bsURL.AsStringC()),
+        CFX_WideString::FromUTF8(bsData.AsStringC()),
+        CFX_WideString::FromUTF8(bsEncode.AsStringC()));
     FXJSE_Value_Release(argOne);
     FXJSE_Value_Release(argTwo);
     if (argc > 2) {
diff --git a/xfa/fxfa/include/fxfa.h b/xfa/fxfa/include/fxfa.h
index a7d1a282ba..871ab71164 100644
--- a/xfa/fxfa/include/fxfa.h
+++ b/xfa/fxfa/include/fxfa.h
@@ -311,25 +311,30 @@ class IXFA_AppProvider {
 
   /**
    * Displays a message box.
-   * @param[in] dwIconType    Icon type, refer to XFA_MBICON.
-   * @param[in] dwButtonType  Button type, refer to XFA_MESSAGEBUTTON.
+   * @param[in] wsMessage    - Message string to display in box.
+   * @param[in] wsTitle      - Title string for box.
+   * @param[in] dwIconType   - Icon type, refer to XFA_MBICON.
+   * @param[in] dwButtonType - Button type, refer to XFA_MESSAGEBUTTON.
    * @return A valid integer representing the value of the button pressed by the
    * user, refer to XFA_ID.
    */
-  virtual int32_t MsgBox(const CFX_WideStringC& wsMessage,
-                         const CFX_WideStringC& wsTitle = FX_WSTRC(L""),
+  virtual int32_t MsgBox(const CFX_WideString& wsMessage,
+                         const CFX_WideString& wsTitle = L"",
                          uint32_t dwIconType = 0,
                          uint32_t dwButtonType = 0) = 0;
 
   /**
    * Get a response from the user.
-   * @param[in] bMark - Mask the user input with * (asterisks) when true,
+   * @param[in] wsQuestion      - Message string to display in box.
+   * @param[in] wsTitle         - Title string for box.
+   * @param[in] wsDefaultAnswer - Initial contents for answer.
+   * @param[in] bMask           - Mask the user input with asterisks when true,
+   * @return A string containing the user's response.
    */
-  virtual void Response(CFX_WideString& wsAnswer,
-                        const CFX_WideStringC& wsQuestion,
-                        const CFX_WideStringC& wsTitle = FX_WSTRC(L""),
-                        const CFX_WideStringC& wsDefaultAnswer = FX_WSTRC(L""),
-                        FX_BOOL bMark = TRUE) = 0;
+  virtual CFX_WideString Response(const CFX_WideString& wsQuestion,
+                                  const CFX_WideString& wsTitle = L"",
+                                  const CFX_WideString& wsDefaultAnswer = L"",
+                                  FX_BOOL bMask = TRUE) = 0;
 
   virtual int32_t GetDocumentCountInBatch() = 0;
   virtual int32_t GetCurDocumentInBatch() = 0;
@@ -339,7 +344,7 @@ class IXFA_AppProvider {
    * @param[in] wsURL - http, ftp, such as
    * "http://www.w3.org/TR/REC-xml-names/".
    */
-  virtual IFX_FileRead* DownloadURL(const CFX_WideStringC& wsURL) = 0;
+  virtual IFX_FileRead* DownloadURL(const CFX_WideString& wsURL) = 0;
 
   /**
    * POST data to the given url.
@@ -356,11 +361,11 @@ class IXFA_AppProvider {
    * @param[out] wsResponse   decoded response from server.
    * @return TRUE Server permitted the post request, FALSE otherwise.
    */
-  virtual FX_BOOL PostRequestURL(const CFX_WideStringC& wsURL,
-                                 const CFX_WideStringC& wsData,
-                                 const CFX_WideStringC& wsContentType,
-                                 const CFX_WideStringC& wsEncode,
-                                 const CFX_WideStringC& wsHeader,
+  virtual FX_BOOL PostRequestURL(const CFX_WideString& wsURL,
+                                 const CFX_WideString& wsData,
+                                 const CFX_WideString& wsContentType,
+                                 const CFX_WideString& wsEncode,
+                                 const CFX_WideString& wsHeader,
                                  CFX_WideString& wsResponse) = 0;
 
   /**
@@ -371,9 +376,9 @@ class IXFA_AppProvider {
    * ISO8859-1, any recognized [IANA]character encoding
    * @return TRUE Server permitted the post request, FALSE otherwise.
    */
-  virtual FX_BOOL PutRequestURL(const CFX_WideStringC& wsURL,
-                                const CFX_WideStringC& wsData,
-                                const CFX_WideStringC& wsEncode) = 0;
+  virtual FX_BOOL PutRequestURL(const CFX_WideString& wsURL,
+                                const CFX_WideString& wsData,
+                                const CFX_WideString& wsEncode) = 0;
 
   virtual void LoadString(int32_t iStringID, CFX_WideString& wsString) = 0;
   virtual IFWL_AdapterTimerMgr* GetTimerMgr() = 0;
@@ -416,12 +421,12 @@ class IXFA_DocProvider {
   virtual void GetTitle(CXFA_FFDoc* hDoc, CFX_WideString& wsTitle) = 0;
   virtual void SetTitle(CXFA_FFDoc* hDoc, const CFX_WideString& wsTitle) = 0;
   virtual void ExportData(CXFA_FFDoc* hDoc,
-                          const CFX_WideStringC& wsFilePath,
+                          const CFX_WideString& wsFilePath,
                           FX_BOOL bXDP = TRUE) = 0;
   virtual void ImportData(CXFA_FFDoc* hDoc,
-                          const CFX_WideStringC& wsFilePath) = 0;
+                          const CFX_WideString& wsFilePath) = 0;
   virtual void GotoURL(CXFA_FFDoc* hDoc,
-                       const CFX_WideStringC& bsURL,
+                       const CFX_WideString& bsURL,
                        FX_BOOL bAppend = TRUE) = 0;
   virtual FX_BOOL IsValidationsEnabled(CXFA_FFDoc* hDoc) = 0;
   virtual void SetValidationsEnabled(CXFA_FFDoc* hDoc, FX_BOOL bEnabled) = 0;
diff --git a/xfa/fxfa/parser/xfa_script_hostpseudomodel.cpp b/xfa/fxfa/parser/xfa_script_hostpseudomodel.cpp
index e6de66d803..94fa8db96c 100644
--- a/xfa/fxfa/parser/xfa_script_hostpseudomodel.cpp
+++ b/xfa/fxfa/parser/xfa_script_hostpseudomodel.cpp
@@ -290,7 +290,7 @@ void CScript_HostPseudoModel::Script_HostPseudoModel_GotoURL(
     CFX_ByteString bsURL = pArguments->GetUTF8String(0);
     wsURL = CFX_WideString::FromUTF8(bsURL.AsStringC());
   }
-  pNotify->GetDocProvider()->GotoURL(hDoc, wsURL.AsStringC());
+  pNotify->GetDocProvider()->GotoURL(hDoc, wsURL);
 }
 void CScript_HostPseudoModel::Script_HostPseudoModel_OpenList(
     CFXJSE_Arguments* pArguments) {
@@ -381,10 +381,8 @@ void CScript_HostPseudoModel::Script_HostPseudoModel_Response(
   if (iLength >= 4) {
     bMark = pArguments->GetInt32(3) == 0 ? FALSE : TRUE;
   }
-  CFX_WideString wsAnswer;
-  pNotify->GetAppProvider()->Response(wsAnswer, wsQuestion.AsStringC(),
-                                      wsTitle.AsStringC(),
-                                      wsDefaultAnswer.AsStringC(), bMark);
+  CFX_WideString wsAnswer = pNotify->GetAppProvider()->Response(
+      wsQuestion, wsTitle, wsDefaultAnswer, bMark);
   FXJSE_HVALUE hValue = pArguments->GetReturnValue();
   if (hValue) {
     FXJSE_Value_SetUTF8String(hValue, FX_UTF8Encode(wsAnswer).AsStringC());
@@ -598,7 +596,7 @@ void CScript_HostPseudoModel::Script_HostPseudoModel_MessageBox(
     }
   }
   int32_t iValue = pNotify->GetAppProvider()->MsgBox(
-      wsMessage.AsStringC(), bsTitle.AsStringC(), dwMessageType, dwButtonType);
+      wsMessage, bsTitle, dwMessageType, dwButtonType);
   FXJSE_HVALUE hValue = pArguments->GetReturnValue();
   if (hValue) {
     FXJSE_Value_SetInteger(hValue, iValue);
@@ -730,7 +728,7 @@ void CScript_HostPseudoModel::Script_HostPseudoModel_ImportData(
     wsFilePath = CFX_WideString::FromUTF8(bsFilePath.AsStringC());
   }
   CXFA_FFDoc* hDoc = pNotify->GetHDOC();
-  pNotify->GetDocProvider()->ImportData(hDoc, wsFilePath.AsStringC());
+  pNotify->GetDocProvider()->ImportData(hDoc, wsFilePath);
 }
 void CScript_HostPseudoModel::Script_HostPseudoModel_ExportData(
     CFXJSE_Arguments* pArguments) {
@@ -753,7 +751,7 @@ void CScript_HostPseudoModel::Script_HostPseudoModel_ExportData(
   if (iLength >= 2) {
     bXDP = pArguments->GetInt32(1) == 0 ? FALSE : TRUE;
   }
-  pNotify->GetDocProvider()->ExportData(hDoc, wsFilePath.AsStringC(), bXDP);
+  pNotify->GetDocProvider()->ExportData(hDoc, wsFilePath, bXDP);
 }
 void CScript_HostPseudoModel::Script_HostPseudoModel_PageUp(
     CFXJSE_Arguments* pArguments) {