Combine StrToInt methods.

This Cl combines the two StrToInt implementations. In doing so I had to add
some more overrides to toDecimalDigit() and add a isDecimalDigit().

BUG=pdfium:423
R=tsepez@chromium.org

Review URL: https://codereview.chromium.org/1757283002 .

3 files changed, 24 insertions, 17 deletions

diff --git a/core/src/fpdfapi/fpdf_font/fpdf_font_cid.cpp b/core/src/fpdfapi/fpdf_font/fpdf_font_cid.cpp
index 3cbd67633f..7c85b8213d 100644
--- a/core/src/fpdfapi/fpdf_font/fpdf_font_cid.cpp
+++ b/core/src/fpdfapi/fpdf_font/fpdf_font_cid.cpp
@@ -720,7 +720,7 @@ FX_DWORD CPDF_CMapParser::CMap_GetCode(const CFX_ByteStringC& word) {
   }
 
   for (int i = 0; i < word.GetLength() && std::isdigit(word.GetAt(i)); ++i)
-    num = num * 10 + FXSYS_toDecimalDigit(word.GetAt(i));
+    num = num * 10 + FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(word.GetAt(i)));
   return num;
 }
 
diff --git a/core/src/fpdfapi/fpdf_page/fpdf_page_parser_old.cpp b/core/src/fpdfapi/fpdf_page/fpdf_page_parser_old.cpp
index 02e3617feb..b49607e743 100644
--- a/core/src/fpdfapi/fpdf_page/fpdf_page_parser_old.cpp
+++ b/core/src/fpdfapi/fpdf_page/fpdf_page_parser_old.cpp
@@ -533,10 +533,11 @@ CFX_ByteString CPDF_StreamParser::ReadString() {
   if (!PositionIsInBounds())
     return CFX_ByteString();
 
-  int ch = m_pBuf[m_Pos++];
+  uint8_t ch = m_pBuf[m_Pos++];
   CFX_ByteTextBuf buf;
   int parlevel = 0;
-  int status = 0, iEscCode = 0;
+  int status = 0;
+  int iEscCode = 0;
   while (1) {
     switch (status) {
       case 0:
@@ -560,7 +561,7 @@ CFX_ByteString CPDF_StreamParser::ReadString() {
         break;
       case 1:
         if (ch >= '0' && ch <= '7') {
-          iEscCode = FXSYS_toDecimalDigit(ch);
+          iEscCode = FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(ch));
           status = 2;
           break;
         }
@@ -585,7 +586,8 @@ CFX_ByteString CPDF_StreamParser::ReadString() {
         break;
       case 2:
         if (ch >= '0' && ch <= '7') {
-          iEscCode = iEscCode * 8 + FXSYS_toDecimalDigit(ch);
+          iEscCode =
+              iEscCode * 8 + FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(ch));
           status = 3;
         } else {
           buf.AppendChar(iEscCode);
@@ -595,7 +597,8 @@ CFX_ByteString CPDF_StreamParser::ReadString() {
         break;
       case 3:
         if (ch >= '0' && ch <= '7') {
-          iEscCode = iEscCode * 8 + FXSYS_toDecimalDigit(ch);
+          iEscCode =
+              iEscCode * 8 + FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(ch));
           buf.AppendChar(iEscCode);
           status = 0;
         } else {
@@ -617,7 +620,7 @@ CFX_ByteString CPDF_StreamParser::ReadString() {
     ch = m_pBuf[m_Pos++];
   }
   if (PositionIsInBounds())
-    ch = m_pBuf[m_Pos++];
+    ++m_Pos;
 
   if (buf.GetLength() > MAX_STRING_LENGTH) {
     return CFX_ByteString(buf.GetBuffer(), MAX_STRING_LENGTH);
diff --git a/core/src/fpdfapi/fpdf_parser/fpdf_parser_parser.cpp b/core/src/fpdfapi/fpdf_parser/fpdf_parser_parser.cpp
index 16d1134cb1..737bbe49be 100644
--- a/core/src/fpdfapi/fpdf_parser/fpdf_parser_parser.cpp
+++ b/core/src/fpdfapi/fpdf_parser/fpdf_parser_parser.cpp
@@ -208,12 +208,12 @@ CPDF_Parser::Error CPDF_Parser::StartParse(IFX_FileRead* pFileAccess) {
   if (!m_Syntax.GetCharAt(5, ch))
     return FORMAT_ERROR;
   if (std::isdigit(ch))
-    m_FileVersion = FXSYS_toDecimalDigit(ch) * 10;
+    m_FileVersion = FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(ch)) * 10;
 
   if (!m_Syntax.GetCharAt(7, ch))
     return FORMAT_ERROR;
   if (std::isdigit(ch))
-    m_FileVersion += FXSYS_toDecimalDigit(ch);
+    m_FileVersion += FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(ch));
 
   if (m_Syntax.m_FileLen < m_Syntax.m_HeaderOffset + 9)
     return FORMAT_ERROR;
@@ -669,7 +669,7 @@ FX_BOOL CPDF_Parser::RebuildCrossRef() {
           if (std::isdigit(byte)) {
             start_pos = pos + i;
             state = ParserState::kObjNum;
-            objnum = FXSYS_toDecimalDigit(byte);
+            objnum = FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(byte));
           } else if (byte == 't') {
             state = ParserState::kTrailer;
             inside_index = 1;
@@ -684,7 +684,8 @@ FX_BOOL CPDF_Parser::RebuildCrossRef() {
 
         case ParserState::kObjNum:
           if (std::isdigit(byte)) {
-            objnum = objnum * 10 + FXSYS_toDecimalDigit(byte);
+            objnum =
+                objnum * 10 + FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(byte));
           } else if (PDFCharIsWhitespace(byte)) {
             state = ParserState::kPostObjNum;
           } else {
@@ -698,7 +699,7 @@ FX_BOOL CPDF_Parser::RebuildCrossRef() {
           if (std::isdigit(byte)) {
             start_pos1 = pos + i;
             state = ParserState::kGenNum;
-            gennum = FXSYS_toDecimalDigit(byte);
+            gennum = FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(byte));
           } else if (byte == 't') {
             state = ParserState::kTrailer;
             inside_index = 1;
@@ -710,7 +711,8 @@ FX_BOOL CPDF_Parser::RebuildCrossRef() {
 
         case ParserState::kGenNum:
           if (std::isdigit(byte)) {
-            gennum = gennum * 10 + FXSYS_toDecimalDigit(byte);
+            gennum =
+                gennum * 10 + FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(byte));
           } else if (PDFCharIsWhitespace(byte)) {
             state = ParserState::kPostGenNum;
           } else {
@@ -725,7 +727,7 @@ FX_BOOL CPDF_Parser::RebuildCrossRef() {
             inside_index = 1;
           } else if (std::isdigit(byte)) {
             objnum = gennum;
-            gennum = FXSYS_toDecimalDigit(byte);
+            gennum = FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(byte));
             start_pos = start_pos1;
             start_pos1 = pos + i;
             state = ParserState::kGenNum;
@@ -1876,7 +1878,7 @@ CFX_ByteString CPDF_SyntaxParser::ReadString() {
         break;
       case 1:
         if (ch >= '0' && ch <= '7') {
-          iEscCode = FXSYS_toDecimalDigit(ch);
+          iEscCode = FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(ch));
           status = 2;
           break;
         }
@@ -1901,7 +1903,8 @@ CFX_ByteString CPDF_SyntaxParser::ReadString() {
         break;
       case 2:
         if (ch >= '0' && ch <= '7') {
-          iEscCode = iEscCode * 8 + FXSYS_toDecimalDigit(ch);
+          iEscCode =
+              iEscCode * 8 + FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(ch));
           status = 3;
         } else {
           buf.AppendChar(iEscCode);
@@ -1911,7 +1914,8 @@ CFX_ByteString CPDF_SyntaxParser::ReadString() {
         break;
       case 3:
         if (ch >= '0' && ch <= '7') {
-          iEscCode = iEscCode * 8 + FXSYS_toDecimalDigit(ch);
+          iEscCode =
+              iEscCode * 8 + FXSYS_toDecimalDigit(static_cast<FX_WCHAR>(ch));
           buf.AppendChar(iEscCode);
           status = 0;
         } else {