add more error handling, address comments

Author: abhina-sree

clang/lib/Lex/LiteralSupport.cpp

@@ -1766,7 +1766,7 @@ CharLiteralParser::CharLiteralParser(const char *begin, const char *end,
  HadError = false;
 
  Kind = kind;
- LiteralConverter *LiteralConv = &PP.getLiteralConverter();
+ LiteralConverter LiteralConv = PP.getLiteralConverter();
 
  const char *TokBegin = begin;
 
@@ -1834,8 +1834,8 @@ CharLiteralParser::CharLiteralParser(const char *begin, const char *end,
  }
 
  llvm::TextEncodingConverter *Converter = nullptr;
- if (!isUTFLiteral(Kind) && !isWideLiteral(Kind) && LiteralConv)
- Converter = LiteralConv->getConverter(CA_ToExecEncoding);
+ if (!isUTFLiteral(Kind) && !isWideLiteral(Kind))
+ Converter = LiteralConv.getConverter(CA_ToExecEncoding);
 
  while (begin != end) {
  // Is this a span of non-escape characters?
@@ -1902,21 +1902,29 @@ CharLiteralParser::CharLiteralParser(const char *begin, const char *end,
  PP.Diag(Loc, diag::err_character_too_large);
  }
  } else {
- char Cp[8];
+ char Cp[5];
  char *ResultPtr = Cp;
- unsigned CharByteWidth = 1;
  EncodeUCNEscape(TokBegin, begin, end, ResultPtr, HadError,
  FullSourceLoc(Loc, PP.getSourceManager()),
- CharByteWidth, &PP.getDiagnostics(), PP.getLangOpts());
+ /*CharByteWidth=*/1u, &PP.getDiagnostics(),
+ PP.getLangOpts());
+ assert(ResultPtr - Cp <= 4 &&
+ "unexpected result size for UCN escape character");
  if (!HadError) {
  SmallString<8> CpConv;
- Converter->convert(StringRef(Cp), CpConv);
- if (CpConv.size() > 1) {
+ StringRef ToConvert(Cp, ResultPtr - Cp);
+ std::error_code EC = Converter->convert(StringRef(Cp), CpConv);
+ if (EC) {
+ PP.Diag(Loc, diag::err_exec_charset_conversion_failed)
+ << EC.message();
  HadError = true;
- PP.Diag(Loc, diag::err_character_too_large);
  } else {
- memcpy(Cp, CpConv.data(), CpConv.size());
- *buffer_begin = *Cp;
+ if (CpConv.size() > 1) {
+ HadError = true;
+ PP.Diag(Loc, diag::err_character_too_large);
+ } else {
+ *buffer_begin = CpConv[0];
+ }
  }
  }
  }
@@ -2048,6 +2056,42 @@ StringLiteralParser::StringLiteralParser(ArrayRef<Token> StringToks,
  init(StringToks, Action);
 }
 
+static char *convertCharactersInPlace(char *ResultPtr, char *ResultPtrBefore,
+ const unsigned CharByteWidth,
+ bool &hadError,
+ llvm::TextEncodingConverter &Converter) {
+ assert(!hadError && "Unexpected call to convertCharactersInPlace");
+
+ SmallString<256> CpConv;
+ int ResultLength = ResultPtr - ResultPtrBefore;
+ assert(ResultLength % CharByteWidth == 0 &&
+ "Unexpected span of bytes for the characters.");
+ char *Cp = ResultPtrBefore;
+ if (Converter.convert(StringRef(Cp, ResultLength / CharByteWidth), CpConv)) {
+ hadError = true;
+ return ResultPtr;
+ }
+ if (CharByteWidth == 1) {
+ memcpy(Cp, CpConv.data(), CpConv.size());
+ return Cp + CpConv.size();
+ }
+ std::string UTF8String;
+ if (CharByteWidth == 4)
+ convertUTF32ToUTF8String(ArrayRef<char>(Cp, ResultLength), UTF8String);
+ else if (CharByteWidth == 2)
+ convertUTF16ToUTF8String(ArrayRef<char>(Cp, ResultLength), UTF8String);
+ if (Converter.convert(UTF8String, CpConv)) {
+ hadError = true;
+ return ResultPtr;
+ }
+ int NewCharByteWidth = ((int)CpConv.size()) / (ResultLength / CharByteWidth);
+ unsigned EndianOffset = llvm::sys::IsBigEndianHost ? CharByteWidth - 1 : 0;
+ for (int i = 0; i < (int)CpConv.size(); i += NewCharByteWidth)
+ memcpy(Cp + EndianOffset + i * CharByteWidth, CpConv.data() + i,
+ NewCharByteWidth);
+ return Cp + CpConv.size() * CharByteWidth;
+}
+
 void StringLiteralParser::init(ArrayRef<Token> StringToks,
  ConversionAction Action) {
  // The literal token may have come from an invalid source location (e.g. due
@@ -2254,28 +2298,19 @@ void StringLiteralParser::init(ArrayRef<Token> StringToks,
  StringRef BeforeCRLF = RemainingTokenSpan.substr(0, CRLFPos);
  StringRef AfterCRLF = RemainingTokenSpan.substr(CRLFPos);
 
+ char *ResultPtrBefore = ResultPtr;
  // Copy everything before the \r\n sequence into the string literal.
  if (CopyStringFragment(StringToks[i], ThisTokBegin, BeforeCRLF))
  hadError = true;
 
  if (!hadError && Converter) {
  assert(Kind != tok::wide_string_literal &&
  "Wide character translation not supported");
- SmallString<256> CpConv;
- int ResultLength = BeforeCRLF.size() * CharByteWidth;
- char *Cp = ResultPtr - ResultLength;
- std::error_code EC =
- Converter->convert(StringRef(Cp, ResultLength), CpConv);
- if (EC) {
- if (Diags)
- Diags->Report(StringToks[i].getLocation(),
- diag::err_exec_charset_conversion_failed)
- << EC.message();
- hadError = true;
- } else {
- memcpy(Cp, CpConv.data(), ResultLength);
- ResultPtr = Cp + CpConv.size();
- }
+ ResultPtr = convertCharactersInPlace(
+ ResultPtr, ResultPtrBefore, CharByteWidth, hadError, *Converter);
+ if (hadError && Diags)
+ Diags->Report(StringToks[i].getLocation(),
+ diag::err_exec_charset_conversion_failed);
  }
  // Point into the \n inside the \r\n sequence and operate on the
  // remaining portion of the literal.
@@ -2311,7 +2346,7 @@ void StringLiteralParser::init(ArrayRef<Token> StringToks,
  ++ThisTokBuf;
  } while (ThisTokBuf != ThisTokEnd && ThisTokBuf[0] != '\\');
 
- int Length = ThisTokBuf - InStart;
+ char *ResultPtrBefore = ResultPtr;
  // Copy the character span over.
  if (CopyStringFragment(StringToks[i], ThisTokBegin,
  StringRef(InStart, ThisTokBuf - InStart)))
@@ -2320,21 +2355,12 @@ void StringLiteralParser::init(ArrayRef<Token> StringToks,
  if (!hadError && Converter) {
  assert(Kind != tok::wide_string_literal &&
  "Wide character translation not supported");
- SmallString<256> CpConv;
- int ResultLength = Length * CharByteWidth;
- char *Cp = ResultPtr - ResultLength;
- std::error_code EC =
- Converter->convert(StringRef(Cp, ResultLength), CpConv);
- if (EC) {
- if (Diags)
- Diags->Report(StringToks[i].getLocation(),
- diag::err_exec_charset_conversion_failed)
- << EC.message();
- hadError = true;
- } else {
- memcpy(Cp, CpConv.data(), ResultLength);
- ResultPtr = Cp + CpConv.size();
- }
+ ResultPtr =
+ convertCharactersInPlace(ResultPtr, ResultPtrBefore,
+ CharByteWidth, hadError, *Converter);
+ if (hadError && Diags)
+ Diags->Report(StringToks[i].getLocation(),
+ diag::err_exec_charset_conversion_failed);
  }
  continue;
  }