Re-enable several MSVC warnings

Re-enable the following warnings:
 4245: signed/unsigned conversion mismatch;
 4310: cast may truncate data;
 4389: operator on signed/unsigned mismatch;
 4701: use potentially uninitialized local variable;
 4706: assignment within conditional expression

Clean up the code to avoid those warnings.

BUG=pdfium:29
R=tsepez@chromium.org

Review URL: https://codereview.chromium.org/1801383002 .

6 files changed, 11 insertions, 14 deletions

diff --git a/fpdfsdk/formfiller/cba_fontmap.cpp b/fpdfsdk/formfiller/cba_fontmap.cpp
index 519c7d8cef..caa0704955 100644
--- a/fpdfsdk/formfiller/cba_fontmap.cpp
+++ b/fpdfsdk/formfiller/cba_fontmap.cpp
@@ -206,8 +206,8 @@ CPDF_Font* CBA_FontMap::GetAnnotDefaultFont(CFX_ByteString& sAlias) {
   }
 
   CFX_ByteString sDA;
-  CPDF_Object* pObj;
-  if ((pObj = FPDF_GetFieldAttr(m_pAnnotDict, "DA")))
+  CPDF_Object* pObj = FPDF_GetFieldAttr(m_pAnnotDict, "DA");
+  if (pObj)
     sDA = pObj->GetString();
 
   if (bWidget) {
diff --git a/fpdfsdk/fpdfppo.cpp b/fpdfsdk/fpdfppo.cpp
index 4377c3ed94..6a72141e7d 100644
--- a/fpdfsdk/fpdfppo.cpp
+++ b/fpdfsdk/fpdfppo.cpp
@@ -86,8 +86,7 @@ FX_BOOL CPDF_PageOrganizer::PDFDocInit(CPDF_Document* pDestPDFDoc,
   CPDF_Array* pKeysArray = pNewPages->GetArrayBy("Kids");
   if (!pKeysArray) {
     CPDF_Array* pNewKids = new CPDF_Array;
-    FX_DWORD Kidsobjnum = -1;
-    Kidsobjnum = pDestPDFDoc->AddIndirectObject(pNewKids);
+    FX_DWORD Kidsobjnum = pDestPDFDoc->AddIndirectObject(pNewKids);
 
     pNewPages->SetAt("Kids", new CPDF_Reference(pDestPDFDoc, Kidsobjnum));
     pNewPages->SetAt("Count", new CPDF_Number(0));
diff --git a/fpdfsdk/fpdftext.cpp b/fpdfsdk/fpdftext.cpp
index cbb8e00a40..24b592a88b 100644
--- a/fpdfsdk/fpdftext.cpp
+++ b/fpdfsdk/fpdftext.cpp
@@ -51,7 +51,7 @@ DLLEXPORT int STDCALL FPDFText_CountChars(FPDF_TEXTPAGE text_page) {
 DLLEXPORT unsigned int STDCALL FPDFText_GetUnicode(FPDF_TEXTPAGE text_page,
                                                    int index) {
   if (!text_page)
-    return -1;
+    return 0;
   IPDF_TextPage* textpage = (IPDF_TextPage*)text_page;
 
   if (index < 0 || index >= textpage->CountChars())
diff --git a/fpdfsdk/fpdfview.cpp b/fpdfsdk/fpdfview.cpp
index 1c9024d836..589a6de644 100644
--- a/fpdfsdk/fpdfview.cpp
+++ b/fpdfsdk/fpdfview.cpp
@@ -282,7 +282,7 @@ int GetLastError() {
 #endif  // _WIN32
 
 void ProcessParseError(CPDF_Parser::Error err) {
-  FX_DWORD err_code;
+  FX_DWORD err_code = FPDF_ERR_SUCCESS;
   // Translate FPDFAPI error code to FPDFVIEW error code
   switch (err) {
     case CPDF_Parser::SUCCESS:
diff --git a/fpdfsdk/fxedit/fxet_ap.cpp b/fpdfsdk/fxedit/fxet_ap.cpp
index 6f064b2ce8..5bf61365c5 100644
--- a/fpdfsdk/fxedit/fxet_ap.cpp
+++ b/fpdfsdk/fxedit/fxet_ap.cpp
@@ -18,12 +18,10 @@ CFX_ByteString GetPDFWordString(IFX_Edit_FontMap* pFontMap,
     if (SubWord > 0) {
       Word = SubWord;
     } else {
-      FX_DWORD dwCharCode = -1;
-
-      if (pPDFFont->IsUnicodeCompatible())
-        dwCharCode = pPDFFont->CharCodeFromUnicode(Word);
-      else
-        dwCharCode = pFontMap->CharCodeFromUnicode(nFontIndex, Word);
+      FX_DWORD dwCharCode =
+          pPDFFont->IsUnicodeCompatible()
+              ? pPDFFont->CharCodeFromUnicode(Word)
+              : pFontMap->CharCodeFromUnicode(nFontIndex, Word);
 
       if (dwCharCode > 0) {
         pPDFFont->AppendChar(sWord, dwCharCode);
diff --git a/fpdfsdk/javascript/Document.cpp b/fpdfsdk/javascript/Document.cpp
index 144d428989..36ea910a47 100644
--- a/fpdfsdk/javascript/Document.cpp
+++ b/fpdfsdk/javascript/Document.cpp
@@ -1459,7 +1459,7 @@ int Document::CountWords(CPDF_TextObject* pTextObj) {
   FX_BOOL bIsLatin = FALSE;
 
   for (int i = 0, sz = pTextObj->CountChars(); i < sz; i++) {
-    FX_DWORD charcode = -1;
+    FX_DWORD charcode = static_cast<FX_DWORD>(-1);
     FX_FLOAT kerning;
 
     pTextObj->GetCharInfo(i, charcode, kerning);
@@ -1492,7 +1492,7 @@ CFX_WideString Document::GetObjWordStr(CPDF_TextObject* pTextObj,
   FX_BOOL bIsLatin = FALSE;
 
   for (int i = 0, sz = pTextObj->CountChars(); i < sz; i++) {
-    FX_DWORD charcode = -1;
+    FX_DWORD charcode = static_cast<FX_DWORD>(-1);
     FX_FLOAT kerning;
 
     pTextObj->GetCharInfo(i, charcode, kerning);