//===--- PrintPreprocessedOutput.cpp - Implement the -E mode --------------===//

//

// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.

// See https://llvm.org/LICENSE.txt for license information.

// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

//

//===----------------------------------------------------------------------===//

//

// This code simply runs the preprocessor on the input file and prints out the

// result.  This is the traditional behavior of the -E option.

//

//===----------------------------------------------------------------------===//

#include "clang/Frontend/Utils.h"

#include "clang/Basic/CharInfo.h"

#include "clang/Basic/Diagnostic.h"

#include "clang/Basic/SourceManager.h"

#include "clang/Frontend/PreprocessorOutputOptions.h"

#include "clang/Lex/MacroInfo.h"

#include "clang/Lex/PPCallbacks.h"

#include "clang/Lex/Pragma.h"

#include "clang/Lex/Preprocessor.h"

#include "clang/Lex/TokenConcatenation.h"

#include "llvm/ADT/STLExtras.h"

#include "llvm/ADT/SmallString.h"

#include "llvm/ADT/StringRef.h"

#include "llvm/Support/ErrorHandling.h"

#include "llvm/Support/raw_ostream.h"

#include <cstdio>

using namespace clang;

/// PrintMacroDefinition - Print a macro definition in a form that will be

/// properly accepted back as a definition.

static void PrintMacroDefinition(const IdentifierInfo &II, const MacroInfo &MI,

                                 Preprocessor &PP, raw_ostream *OS) {

  *OS << "#define " << II.getName();

  if (MI.isFunctionLike()) {

    *OS << '(';

    if (!MI.param_empty()) {

      MacroInfo::param_iterator AI = MI.param_begin(), E = MI.param_end();

      for (; AI+1 != E; ++AI) {

        *OS << (*AI)->getName();

        *OS << ',';

      }

      // Last argument.

      if ((*AI)->getName() == "__VA_ARGS__")

        *OS << "...";

      else

        *OS << (*AI)->getName();

    }

    if (MI.isGNUVarargs())

      *OS << "...";  // #define foo(x...)

    *OS << ')';

  }

  // GCC always emits a space, even if the macro body is empty.  However, do not

  // want to emit two spaces if the first token has a leading space.

  if (MI.tokens_empty() || !MI.tokens_begin()->hasLeadingSpace())

    *OS << ' ';

  SmallString<128> SpellingBuffer;

  for (const auto &T : MI.tokens()) {

    if (T.hasLeadingSpace())

      *OS << ' ';

    *OS << PP.getSpelling(T, SpellingBuffer);

  }

}

//===----------------------------------------------------------------------===//

// Preprocessed token printer

//===----------------------------------------------------------------------===//

namespace {

class PrintPPOutputPPCallbacks : public PPCallbacks {

  Preprocessor &PP;

  SourceManager &SM;

  TokenConcatenation ConcatInfo;

public:

  raw_ostream *OS;

private:

  unsigned CurLine;

  bool EmittedTokensOnThisLine;

  bool EmittedDirectiveOnThisLine;

  SrcMgr::CharacteristicKind FileType;

  SmallString<512> CurFilename;

  bool Initialized;

  bool DisableLineMarkers;

  bool DumpDefines;

  bool DumpIncludeDirectives;

  bool UseLineDirectives;

  bool IsFirstFileEntered;

  bool MinimizeWhitespace;

  bool DirectivesOnly;

  bool KeepSystemIncludes;

  raw_ostream *OrigOS;

  std::unique_ptr<llvm::raw_null_ostream> NullOS;

  Token PrevTok;

  Token PrevPrevTok;

public:

  PrintPPOutputPPCallbacks(Preprocessor &pp, raw_ostream *os, bool lineMarkers,

                           bool defines, bool DumpIncludeDirectives,

                           bool UseLineDirectives, bool MinimizeWhitespace,

                           bool DirectivesOnly, bool KeepSystemIncludes)

      : PP(pp), SM(PP.getSourceManager()), ConcatInfo(PP), OS(os),

        DisableLineMarkers(lineMarkers), DumpDefines(defines),

        DumpIncludeDirectives(DumpIncludeDirectives),

        UseLineDirectives(UseLineDirectives),

        MinimizeWhitespace(MinimizeWhitespace), DirectivesOnly(DirectivesOnly),

        KeepSystemIncludes(KeepSystemIncludes), OrigOS(os) {

    CurLine = 0;

    CurFilename += "<uninit>";

    EmittedTokensOnThisLine = false;

    EmittedDirectiveOnThisLine = false;

    FileType = SrcMgr::C_User;

    Initialized = false;

    IsFirstFileEntered = false;

    if (KeepSystemIncludes)

      NullOS = std::make_unique<llvm::raw_null_ostream>();

    PrevTok.startToken();

    PrevPrevTok.startToken();

  }

  bool isMinimizeWhitespace() const { return MinimizeWhitespace; }

  void setEmittedTokensOnThisLine() { EmittedTokensOnThisLine = true; }

  bool hasEmittedTokensOnThisLine() const { return EmittedTokensOnThisLine; }

  void setEmittedDirectiveOnThisLine() { EmittedDirectiveOnThisLine = true; }

  bool hasEmittedDirectiveOnThisLine() const {

    return EmittedDirectiveOnThisLine;

  }

  /// Ensure that the output stream position is at the beginning of a new line

  /// and inserts one if it does not. It is intended to ensure that directives

  /// inserted by the directives not from the input source (such as #line) are

  /// in the first column. To insert newlines that represent the input, use

  /// MoveToLine(/*...*/, /*RequireStartOfLine=*/true).

  void startNewLineIfNeeded();

  void FileChanged(SourceLocation Loc, FileChangeReason Reason,

                   SrcMgr::CharacteristicKind FileType,

                   FileID PrevFID) override;

  void InclusionDirective(SourceLocation HashLoc, const Token &IncludeTok,

                          StringRef FileName, bool IsAngled,

                          CharSourceRange FilenameRange,

                          OptionalFileEntryRef File, StringRef SearchPath,

                          StringRef RelativePath, const Module *Imported,

                          SrcMgr::CharacteristicKind FileType) override;

  void Ident(SourceLocation Loc, StringRef str) override;

  void PragmaMessage(SourceLocation Loc, StringRef Namespace,

                     PragmaMessageKind Kind, StringRef Str) override;

  void PragmaDebug(SourceLocation Loc, StringRef DebugType) override;

  void PragmaDiagnosticPush(SourceLocation Loc, StringRef Namespace) override;

  void PragmaDiagnosticPop(SourceLocation Loc, StringRef Namespace) override;

  void PragmaDiagnostic(SourceLocation Loc, StringRef Namespace,

                        diag::Severity Map, StringRef Str) override;

  void PragmaWarning(SourceLocation Loc, PragmaWarningSpecifier WarningSpec,

                     ArrayRef<int> Ids) override;

  void PragmaWarningPush(SourceLocation Loc, int Level) override;

  void PragmaWarningPop(SourceLocation Loc) override;

  void PragmaExecCharsetPush(SourceLocation Loc, StringRef Str) override;

  void PragmaExecCharsetPop(SourceLocation Loc) override;

  void PragmaAssumeNonNullBegin(SourceLocation Loc) override;

  void PragmaAssumeNonNullEnd(SourceLocation Loc) override;

  /// Insert whitespace before emitting the next token.

  ///

  /// @param Tok             Next token to be emitted.

  /// @param RequireSpace    Ensure at least one whitespace is emitted. Useful

  ///                        if non-tokens have been emitted to the stream.

  /// @param RequireSameLine Never emit newlines. Useful when semantics depend

  ///                        on being on the same line, such as directives.

  void HandleWhitespaceBeforeTok(const Token &Tok, bool RequireSpace,

                                 bool RequireSameLine);

  /// Move to the line of the provided source location. This will

  /// return true if a newline was inserted or if

  /// the requested location is the first token on the first line.

  /// In these cases the next output will be the first column on the line and

  /// make it possible to insert indention. The newline was inserted

  /// implicitly when at the beginning of the file.

  ///

  /// @param Tok                 Token where to move to.

  /// @param RequireStartOfLine  Whether the next line depends on being in the

  ///                            first column, such as a directive.

  ///

  /// @return Whether column adjustments are necessary.

  bool MoveToLine(const Token &Tok, bool RequireStartOfLine) {

    PresumedLoc PLoc = SM.getPresumedLoc(Tok.getLocation());

    unsigned TargetLine = PLoc.isValid() ? PLoc.getLine() : CurLine;

    bool IsFirstInFile =

        Tok.isAtStartOfLine() && PLoc.isValid() && PLoc.getLine() == 1;

    return MoveToLine(TargetLine, RequireStartOfLine) || IsFirstInFile;

  }

  /// Move to the line of the provided source location. Returns true if a new

  /// line was inserted.

  bool MoveToLine(SourceLocation Loc, bool RequireStartOfLine) {

    PresumedLoc PLoc = SM.getPresumedLoc(Loc);

    unsigned TargetLine = PLoc.isValid() ? PLoc.getLine() : CurLine;

    return MoveToLine(TargetLine, RequireStartOfLine);

  }

  bool MoveToLine(unsigned LineNo, bool RequireStartOfLine);

  bool AvoidConcat(const Token &PrevPrevTok, const Token &PrevTok,

                   const Token &Tok) {

    return ConcatInfo.AvoidConcat(PrevPrevTok, PrevTok, Tok);

  }

  void WriteLineInfo(unsigned LineNo, const char *Extra=nullptr,

                     unsigned ExtraLen=0);

  bool LineMarkersAreDisabled() const { return DisableLineMarkers; }

  void HandleNewlinesInToken(const char *TokStr, unsigned Len);

  /// MacroDefined - This hook is called whenever a macro definition is seen.

  void MacroDefined(const Token &MacroNameTok,

                    const MacroDirective *MD) override;

  /// MacroUndefined - This hook is called whenever a macro #undef is seen.

  void MacroUndefined(const Token &MacroNameTok,

                      const MacroDefinition &MD,

                      const MacroDirective *Undef) override;

  void BeginModule(const Module *M);

  void EndModule(const Module *M);

};

}  // end anonymous namespace

void PrintPPOutputPPCallbacks::WriteLineInfo(unsigned LineNo,

                                             const char *Extra,

                                             unsigned ExtraLen) {

  startNewLineIfNeeded();

  // Emit #line directives or GNU line markers depending on what mode we're in.

  if (UseLineDirectives) {

    *OS << "#line" << ' ' << LineNo << ' ' << '"';

    OS->write_escaped(CurFilename);

    *OS << '"';

  } else {

    *OS << '#' << ' ' << LineNo << ' ' << '"';

    OS->write_escaped(CurFilename);

    *OS << '"';

    if (ExtraLen)

      OS->write(Extra, ExtraLen);

    if (FileType == SrcMgr::C_System)

      OS->write(" 3", 2);

    else if (FileType == SrcMgr::C_ExternCSystem)

      OS->write(" 3 4", 4);

  }

  *OS << '\n';

}

/// MoveToLine - Move the output to the source line specified by the location

/// object.  We can do this by emitting some number of \n's, or be emitting a

/// #line directive.  This returns false if already at the specified line, true

/// if some newlines were emitted.

bool PrintPPOutputPPCallbacks::MoveToLine(unsigned LineNo,

                                          bool RequireStartOfLine) {

  // If it is required to start a new line or finish the current, insert

  // vertical whitespace now and take it into account when moving to the

  // expected line.

  bool StartedNewLine = false;

  if ((RequireStartOfLine && EmittedTokensOnThisLine) ||

      EmittedDirectiveOnThisLine) {

    *OS << '\n';

    StartedNewLine = true;

    CurLine += 1;

    EmittedTokensOnThisLine = false;

    EmittedDirectiveOnThisLine = false;

  }

  // If this line is "close enough" to the original line, just print newlines,

  // otherwise print a #line directive.

  if (CurLine == LineNo) {

    // Nothing to do if we are already on the correct line.

  } else if (MinimizeWhitespace && DisableLineMarkers) {

    // With -E -P -fminimize-whitespace, don't emit anything if not necessary.

  } else if (!StartedNewLine && LineNo - CurLine == 1) {

    // Printing a single line has priority over printing a #line directive, even

    // when minimizing whitespace which otherwise would print #line directives

    // for every single line.

    *OS << '\n';

    StartedNewLine = true;

  } else if (!DisableLineMarkers) {

    if (LineNo - CurLine <= 8) {

      const char *NewLines = "\n\n\n\n\n\n\n\n";

      OS->write(NewLines, LineNo - CurLine);

    } else {

      // Emit a #line or line marker.

      WriteLineInfo(LineNo, nullptr, 0);

    }

    StartedNewLine = true;

  } else if (EmittedTokensOnThisLine) {

    // If we are not on the correct line and don't need to be line-correct,

    // at least ensure we start on a new line.

    *OS << '\n';

    StartedNewLine = true;

  }

  if (StartedNewLine) {

    EmittedTokensOnThisLine = false;

    EmittedDirectiveOnThisLine = false;

  }

  CurLine = LineNo;

  return StartedNewLine;

}

void PrintPPOutputPPCallbacks::startNewLineIfNeeded() {

  if (EmittedTokensOnThisLine || EmittedDirectiveOnThisLine) {

    *OS << '\n';

    EmittedTokensOnThisLine = false;

    EmittedDirectiveOnThisLine = false;

  }

}

/// FileChanged - Whenever the preprocessor enters or exits a #include file

/// it invokes this handler.  Update our conception of the current source

/// position.

void PrintPPOutputPPCallbacks::FileChanged(SourceLocation Loc,

                                           FileChangeReason Reason,

                                       SrcMgr::CharacteristicKind NewFileType,

                                       FileID PrevFID) {

  // Unless we are exiting a #include, make sure to skip ahead to the line the

  // #include directive was at.

  SourceManager &SourceMgr = SM;

  PresumedLoc UserLoc = SourceMgr.getPresumedLoc(Loc);

  if (UserLoc.isInvalid())

    return;

  unsigned NewLine = UserLoc.getLine();

  if (Reason == PPCallbacks::EnterFile) {

    SourceLocation IncludeLoc = UserLoc.getIncludeLoc();

    if (IncludeLoc.isValid())

      MoveToLine(IncludeLoc, /*RequireStartOfLine=*/false);

  } else if (Reason == PPCallbacks::SystemHeaderPragma) {

    // GCC emits the # directive for this directive on the line AFTER the

    // directive and emits a bunch of spaces that aren't needed. This is because

    // otherwise we will emit a line marker for THIS line, which requires an

    // extra blank line after the directive to avoid making all following lines

    // off by one. We can do better by simply incrementing NewLine here.

    NewLine += 1;

  }

  CurLine = NewLine;

  // In KeepSystemIncludes mode, redirect OS as needed.

  if (KeepSystemIncludes && (isSystem(FileType) != isSystem(NewFileType)))

    OS = isSystem(FileType) ? OrigOS : NullOS.get();

  CurFilename.clear();

  CurFilename += UserLoc.getFilename();

  FileType = NewFileType;

  if (DisableLineMarkers) {

    if (!MinimizeWhitespace)

      startNewLineIfNeeded();

    return;

  }

  if (!Initialized) {

    WriteLineInfo(CurLine);

    Initialized = true;

  }

  // Do not emit an enter marker for the main file (which we expect is the first

  // entered file). This matches gcc, and improves compatibility with some tools

  // which track the # line markers as a way to determine when the preprocessed

  // output is in the context of the main file.

  if (Reason == PPCallbacks::EnterFile && !IsFirstFileEntered) {

    IsFirstFileEntered = true;

    return;

  }

  switch (Reason) {

  case PPCallbacks::EnterFile:

    WriteLineInfo(CurLine, " 1", 2);

    break;

  case PPCallbacks::ExitFile:

    WriteLineInfo(CurLine, " 2", 2);

    break;

  case PPCallbacks::SystemHeaderPragma:

  case PPCallbacks::RenameFile:

    WriteLineInfo(CurLine);

    break;

  }

}

void PrintPPOutputPPCallbacks::InclusionDirective(

    SourceLocation HashLoc, const Token &IncludeTok, StringRef FileName,

    bool IsAngled, CharSourceRange FilenameRange, OptionalFileEntryRef File,

    StringRef SearchPath, StringRef RelativePath, const Module *Imported,

    SrcMgr::CharacteristicKind FileType) {

  // In -dI mode, dump #include directives prior to dumping their content or

  // interpretation. Similar for -fkeep-system-includes.

  if (DumpIncludeDirectives || (KeepSystemIncludes && isSystem(FileType))) {

    MoveToLine(HashLoc, /*RequireStartOfLine=*/true);

    const std::string TokenText = PP.getSpelling(IncludeTok);

    assert(!TokenText.empty());

    *OS << "#" << TokenText << " "

        << (IsAngled ? '<' : '"') << FileName << (IsAngled ? '>' : '"')

        << " /* clang -E "

        << (DumpIncludeDirectives ? "-dI" : "-fkeep-system-includes")

        << " */";

    setEmittedDirectiveOnThisLine();

  }

  // When preprocessing, turn implicit imports into module import pragmas.

  if (Imported) {

    switch (IncludeTok.getIdentifierInfo()->getPPKeywordID()) {

    case tok::pp_include:

    case tok::pp_import:

    case tok::pp_include_next:

      MoveToLine(HashLoc, /*RequireStartOfLine=*/true);

      *OS << "#pragma clang module import "

          << Imported->getFullModuleName(true)

          << " /* clang -E: implicit import for "

          << "#" << PP.getSpelling(IncludeTok) << " "

          << (IsAngled ? '<' : '"') << FileName << (IsAngled ? '>' : '"')

          << " */";

      setEmittedDirectiveOnThisLine();

      break;

    case tok::pp___include_macros:

      // #__include_macros has no effect on a user of a preprocessed source

      // file; the only effect is on preprocessing.

      //

      // FIXME: That's not *quite* true: it causes the module in question to

      // be loaded, which can affect downstream diagnostics.

      break;

    default:

      llvm_unreachable("unknown include directive kind");

      break;

    }

  }

}

/// Handle entering the scope of a module during a module compilation.

void PrintPPOutputPPCallbacks::BeginModule(const Module *M) {

  startNewLineIfNeeded();

  *OS << "#pragma clang module begin " << M->getFullModuleName(true);

  setEmittedDirectiveOnThisLine();

}

/// Handle leaving the scope of a module during a module compilation.

void PrintPPOutputPPCallbacks::EndModule(const Module *M) {

  startNewLineIfNeeded();

  *OS << "#pragma clang module end /*" << M->getFullModuleName(true) << "*/";

  setEmittedDirectiveOnThisLine();

}

/// Ident - Handle #ident directives when read by the preprocessor.

///

void PrintPPOutputPPCallbacks::Ident(SourceLocation Loc, StringRef S) {

  MoveToLine(Loc, /*RequireStartOfLine=*/true);

  OS->write("#ident ", strlen("#ident "));

  OS->write(S.begin(), S.size());

  setEmittedTokensOnThisLine();

}

/// MacroDefined - This hook is called whenever a macro definition is seen.

void PrintPPOutputPPCallbacks::MacroDefined(const Token &MacroNameTok,

                                            const MacroDirective *MD) {

  const MacroInfo *MI = MD->getMacroInfo();

  // Print out macro definitions in -dD mode and when we have -fdirectives-only

  // for C++20 header units.

  if ((!DumpDefines && !DirectivesOnly) ||

      // Ignore __FILE__ etc.

      MI->isBuiltinMacro())

    return;

  SourceLocation DefLoc = MI->getDefinitionLoc();

  if (DirectivesOnly && !MI->isUsed()) {

    SourceManager &SM = PP.getSourceManager();

    if (SM.isWrittenInBuiltinFile(DefLoc) ||

        SM.isWrittenInCommandLineFile(DefLoc))

      return;

  }

  MoveToLine(DefLoc, /*RequireStartOfLine=*/true);

  PrintMacroDefinition(*MacroNameTok.getIdentifierInfo(), *MI, PP, OS);

  setEmittedDirectiveOnThisLine();

}

void PrintPPOutputPPCallbacks::MacroUndefined(const Token &MacroNameTok,

                                              const MacroDefinition &MD,

                                              const MacroDirective *Undef) {

  // Print out macro definitions in -dD mode and when we have -fdirectives-only

  // for C++20 header units.

  if (!DumpDefines && !DirectivesOnly)

    return;

  MoveToLine(MacroNameTok.getLocation(), /*RequireStartOfLine=*/true);

  *OS << "#undef " << MacroNameTok.getIdentifierInfo()->getName();

  setEmittedDirectiveOnThisLine();

}

static void outputPrintable(raw_ostream *OS, StringRef Str) {

  for (unsigned char Char : Str) {

    if (isPrintable(Char) && Char != '\\' && Char != '"')

      *OS << (char)Char;

    else // Output anything hard as an octal escape.

      *OS << '\\'

          << (char)('0' + ((Char >> 6) & 7))

          << (char)('0' + ((Char >> 3) & 7))

          << (char)('0' + ((Char >> 0) & 7));

  }

}

void PrintPPOutputPPCallbacks::PragmaMessage(SourceLocation Loc,

                                             StringRef Namespace,

                                             PragmaMessageKind Kind,

                                             StringRef Str) {

  MoveToLine(Loc, /*RequireStartOfLine=*/true);

  *OS << "#pragma ";

  if (!Namespace.empty())

    *OS << Namespace << ' ';

  switch (Kind) {

    case PMK_Message:

      *OS << "message(\"";

      break;

    case PMK_Warning:

      *OS << "warning \"";

      break;

    case PMK_Error:

      *OS << "error \"";

      break;

  }

  outputPrintable(OS, Str);

  *OS << '"';

  if (Kind == PMK_Message)

    *OS << ')';

  setEmittedDirectiveOnThisLine();

}

void PrintPPOutputPPCallbacks::PragmaDebug(SourceLocation Loc,

                                           StringRef DebugType) {

  MoveToLine(Loc, /*RequireStartOfLine=*/true);

  *OS << "#pragma clang __debug ";

  *OS << DebugType;

  setEmittedDirectiveOnThisLine();

}

void PrintPPOutputPPCallbacks::

PragmaDiagnosticPush(SourceLocation Loc, StringRef Namespace) {

  MoveToLine(Loc, /*RequireStartOfLine=*/true);

  *OS << "#pragma " << Namespace << " diagnostic push";

  setEmittedDirectiveOnThisLine();

}

void PrintPPOutputPPCallbacks::

PragmaDiagnosticPop(SourceLocation Loc, StringRef Namespace) {

  MoveToLine(Loc, /*RequireStartOfLine=*/true);

  *OS << "#pragma " << Namespace << " diagnostic pop";

  setEmittedDirectiveOnThisLine();

}

void PrintPPOutputPPCallbacks::PragmaDiagnostic(SourceLocation Loc,

                                                StringRef Namespace,

                                                diag::Severity Map,

                                                StringRef Str) {

  MoveToLine(Loc, /*RequireStartOfLine=*/true);

  *OS << "#pragma " << Namespace << " diagnostic ";

  switch (Map) {

  case diag::Severity::Remark:

    *OS << "remark";

    break;

  case diag::Severity::Warning:

    *OS << "warning";

    break;

  case diag::Severity::Error:

    *OS << "error";

    break;

  case diag::Severity::Ignored:

    *OS << "ignored";

    break;

  case diag::Severity::Fatal:

    *OS << "fatal";

    break;

  }

  *OS << " \"" << Str << '"';

  setEmittedDirectiveOnThisLine();

}

void PrintPPOutputPPCallbacks::PragmaWarning(SourceLocation Loc,

                                             PragmaWarningSpecifier WarningSpec,

                                             ArrayRef<int> Ids) {

  MoveToLine(Loc, /*RequireStartOfLine=*/true);

  *OS << "#pragma warning(";

  switch(WarningSpec) {

    case PWS_Default:  *OS << "default"; break;

    case PWS_Disable:  *OS << "disable"; break;

    case PWS_Error:    *OS << "error"; break;

    case PWS_Once:     *OS << "once"; break;

    case PWS_Suppress: *OS << "suppress"; break;

    case PWS_Level1:   *OS << '1'; break;

    case PWS_Level2:   *OS << '2'; break;

    case PWS_Level3:   *OS << '3'; break;

    case PWS_Level4:   *OS << '4'; break;

  }

  *OS << ':';

  for (ArrayRef<int>::iterator I = Ids.begin(), E = Ids.end(); I != E; ++I)

    *OS << ' ' << *I;

  *OS << ')';

  setEmittedDirectiveOnThisLine();

}

void PrintPPOutputPPCallbacks::PragmaWarningPush(SourceLocation Loc,

                                                 int Level) {

  MoveToLine(Loc, /*RequireStartOfLine=*/true);

  *OS << "#pragma warning(push";

  if (Level >= 0)

    *OS << ", " << Level;

  *OS << ')';

  setEmittedDirectiveOnThisLine();

}

void PrintPPOutputPPCallbacks::PragmaWarningPop(SourceLocation Loc) {

  MoveToLine(Loc, /*RequireStartOfLine=*/true);

  *OS << "#pragma warning(pop)";

  setEmittedDirectiveOnThisLine();

}

void PrintPPOutputPPCallbacks::PragmaExecCharsetPush(SourceLocation Loc,

                                                     StringRef Str) {

  MoveToLine(Loc, /*RequireStartOfLine=*/true);

  *OS << "#pragma character_execution_set(push";

  if (!Str.empty())

    *OS << ", " << Str;

  *OS << ')';

  setEmittedDirectiveOnThisLine();

}

void PrintPPOutputPPCallbacks::PragmaExecCharsetPop(SourceLocation Loc) {

  MoveToLine(Loc, /*RequireStartOfLine=*/true);

  *OS << "#pragma character_execution_set(pop)";

  setEmittedDirectiveOnThisLine();

}

void PrintPPOutputPPCallbacks::

PragmaAssumeNonNullBegin(SourceLocation Loc) {

  MoveToLine(Loc, /*RequireStartOfLine=*/true);

  *OS << "#pragma clang assume_nonnull begin";

  setEmittedDirectiveOnThisLine();

}

void PrintPPOutputPPCallbacks::

PragmaAssumeNonNullEnd(SourceLocation Loc) {

  MoveToLine(Loc, /*RequireStartOfLine=*/true);

  *OS << "#pragma clang assume_nonnull end";

  setEmittedDirectiveOnThisLine();

}

void PrintPPOutputPPCallbacks::HandleWhitespaceBeforeTok(const Token &Tok,

                                                         bool RequireSpace,

                                                         bool RequireSameLine) {

  // These tokens are not expanded to anything and don't need whitespace before

  // them.

  if (Tok.is(tok::eof) ||

      (Tok.isAnnotation() && !Tok.is(tok::annot_header_unit) &&

       !Tok.is(tok::annot_module_begin) && !Tok.is(tok::annot_module_end) &&

       !Tok.is(tok::annot_repl_input_end)))

    return;

  // EmittedDirectiveOnThisLine takes priority over RequireSameLine.

  if ((!RequireSameLine || EmittedDirectiveOnThisLine) &&

      MoveToLine(Tok, /*RequireStartOfLine=*/EmittedDirectiveOnThisLine)) {

    if (MinimizeWhitespace) {

      // Avoid interpreting hash as a directive under -fpreprocessed.

      if (Tok.is(tok::hash))

        *OS << ' ';

    } else {

      // Print out space characters so that the first token on a line is

      // indented for easy reading.

      unsigned ColNo = SM.getExpansionColumnNumber(Tok.getLocation());

      // The first token on a line can have a column number of 1, yet still

      // expect leading white space, if a macro expansion in column 1 starts

      // with an empty macro argument, or an empty nested macro expansion. In

      // this case, move the token to column 2.

      if (ColNo == 1 && Tok.hasLeadingSpace())

        ColNo = 2;

      // This hack prevents stuff like:

      // #define HASH #

      // HASH define foo bar

      // From having the # character end up at column 1, which makes it so it

      // is not handled as a #define next time through the preprocessor if in

      // -fpreprocessed mode.

      if (ColNo <= 1 && Tok.is(tok::hash))

        *OS << ' ';

      // Otherwise, indent the appropriate number of spaces.

      for (; ColNo > 1; --ColNo)

        *OS << ' ';

    }

  } else {

    // Insert whitespace between the previous and next token if either

    // - The caller requires it

    // - The input had whitespace between them and we are not in

    //   whitespace-minimization mode

    // - The whitespace is necessary to keep the tokens apart and there is not

    //   already a newline between them

    if (RequireSpace || (!MinimizeWhitespace && Tok.hasLeadingSpace()) ||

        ((EmittedTokensOnThisLine || EmittedDirectiveOnThisLine) &&

         AvoidConcat(PrevPrevTok, PrevTok, Tok)))

      *OS << ' ';

  }

  PrevPrevTok = PrevTok;

  PrevTok = Tok;

}

void PrintPPOutputPPCallbacks::HandleNewlinesInToken(const char *TokStr,

                                                     unsigned Len) {

  unsigned NumNewlines = 0;

  for (; Len; --Len, ++TokStr) {

    if (*TokStr != '\n' &&

        *TokStr != '\r')

      continue;

    ++NumNewlines;

    // If we have \n\r or \r\n, skip both and count as one line.

    if (Len != 1 &&

        (TokStr[1] == '\n' || TokStr[1] == '\r') &&

        TokStr[0] != TokStr[1]) {

      ++TokStr;

      --Len;

    }

  }

  if (NumNewlines == 0) return;

  CurLine += NumNewlines;

}

namespace {

struct UnknownPragmaHandler : public PragmaHandler {

  const char *Prefix;

  PrintPPOutputPPCallbacks *Callbacks;

  // Set to true if tokens should be expanded

  bool ShouldExpandTokens;

  UnknownPragmaHandler(const char *prefix, PrintPPOutputPPCallbacks *callbacks,

                       bool RequireTokenExpansion)

      : Prefix(prefix), Callbacks(callbacks),

        ShouldExpandTokens(RequireTokenExpansion) {}

  void HandlePragma(Preprocessor &PP, PragmaIntroducer Introducer,

                    Token &PragmaTok) override {

    // Figure out what line we went to and insert the appropriate number of

    // newline characters.

    Callbacks->MoveToLine(PragmaTok.getLocation(), /*RequireStartOfLine=*/true);

    Callbacks->OS->write(Prefix, strlen(Prefix));

    Callbacks->setEmittedTokensOnThisLine();

    if (ShouldExpandTokens) {

      // The first token does not have expanded macros. Expand them, if

      // required.

      auto Toks = std::make_unique<Token[]>(1);

      Toks[0] = PragmaTok;

      PP.EnterTokenStream(std::move(Toks), /*NumToks=*/1,

                          /*DisableMacroExpansion=*/false,

                          /*IsReinject=*/false);

      PP.Lex(PragmaTok);

    }

    // Read and print all of the pragma tokens.

    bool IsFirst = true;

    while (PragmaTok.isNot(tok::eod)) {

      Callbacks->HandleWhitespaceBeforeTok(PragmaTok, /*RequireSpace=*/IsFirst,

                                           /*RequireSameLine=*/true);

      IsFirst = false;

      std::string TokSpell = PP.getSpelling(PragmaTok);

      Callbacks->OS->write(&TokSpell[0], TokSpell.size());

      Callbacks->setEmittedTokensOnThisLine();

      if (ShouldExpandTokens)

        PP.Lex(PragmaTok);

      else

        PP.LexUnexpandedToken(PragmaTok);

    }

    Callbacks->setEmittedDirectiveOnThisLine();

  }

};

} // end anonymous namespace

static void PrintPreprocessedTokens(Preprocessor &PP, Token &Tok,

                                    PrintPPOutputPPCallbacks *Callbacks) {

  bool DropComments = PP.getLangOpts().TraditionalCPP &&

                      !PP.getCommentRetentionState();

  bool IsStartOfLine = false;

  char Buffer[256];

  while (true) {

    // Two lines joined with line continuation ('\' as last character on the

    // line) must be emitted as one line even though Tok.getLine() returns two

    // different values. In this situation Tok.isAtStartOfLine() is false even

    // though it may be the first token on the lexical line. When

    // dropping/skipping a token that is at the start of a line, propagate the

    // start-of-line-ness to the next token to not append it to the previous

    // line.

    IsStartOfLine = IsStartOfLine || Tok.isAtStartOfLine();

    Callbacks->HandleWhitespaceBeforeTok(Tok, /*RequireSpace=*/false,

                                         /*RequireSameLine=*/!IsStartOfLine);

    if (DropComments && Tok.is(tok::comment)) {

      // Skip comments. Normally the preprocessor does not generate

      // tok::comment nodes at all when not keeping comments, but under

      // -traditional-cpp the lexer keeps /all/ whitespace, including comments.

      PP.Lex(Tok);

      continue;

    } else if (Tok.is(tok::annot_repl_input_end)) {

      PP.Lex(Tok);

      continue;

    } else if (Tok.is(tok::eod)) {

      // Don't print end of directive tokens, since they are typically newlines

      // that mess up our line tracking. These come from unknown pre-processor

      // directives or hash-prefixed comments in standalone assembly files.

      PP.Lex(Tok);

      // FIXME: The token on the next line after #include should have

      // Tok.isAtStartOfLine() set.

      IsStartOfLine = true;

      continue;

    } else if (Tok.is(tok::annot_module_include)) {

      // PrintPPOutputPPCallbacks::InclusionDirective handles producing

      // appropriate output here. Ignore this token entirely.

      PP.Lex(Tok);

      IsStartOfLine = true;

      continue;

    } else if (Tok.is(tok::annot_module_begin)) {

      // FIXME: We retrieve this token after the FileChanged callback, and

      // retrieve the module_end token before the FileChanged callback, so

      // we render this within the file and render the module end outside the

      // file, but this is backwards from the token locations: the module_begin

      // token is at the include location (outside the file) and the module_end

      // token is at the EOF location (within the file).

      Callbacks->BeginModule(

          reinterpret_cast<Module *>(Tok.getAnnotationValue()));

      PP.Lex(Tok);

      IsStartOfLine = true;

      continue;

    } else if (Tok.is(tok::annot_module_end)) {

      Callbacks->EndModule(

          reinterpret_cast<Module *>(Tok.getAnnotationValue()));

      PP.Lex(Tok);

      IsStartOfLine = true;

      continue;

    } else if (Tok.is(tok::annot_header_unit)) {

      // This is a header-name that has been (effectively) converted into a

      // module-name.

      // FIXME: The module name could contain non-identifier module name

      // components. We don't have a good way to round-trip those.

      Module *M = reinterpret_cast<Module *>(Tok.getAnnotationValue());

      std::string Name = M->getFullModuleName();

      Callbacks->OS->write(Name.data(), Name.size());

      Callbacks->HandleNewlinesInToken(Name.data(), Name.size());

    } else if (Tok.isAnnotation()) {

      // Ignore annotation tokens created by pragmas - the pragmas themselves

      // will be reproduced in the preprocessed output.

      PP.Lex(Tok);

      continue;

    } else if (IdentifierInfo *II = Tok.getIdentifierInfo()) {

      *Callbacks->OS << II->getName();

    } else if (Tok.isLiteral() && !Tok.needsCleaning() &&

               Tok.getLiteralData()) {

      Callbacks->OS->write(Tok.getLiteralData(), Tok.getLength());

    } else if (Tok.getLength() < std::size(Buffer)) {

      const char *TokPtr = Buffer;

      unsigned Len = PP.getSpelling(Tok, TokPtr);

      Callbacks->OS->write(TokPtr, Len);

      // Tokens that can contain embedded newlines need to adjust our current

      // line number.

      // FIXME: The token may end with a newline in which case

      // setEmittedDirectiveOnThisLine/setEmittedTokensOnThisLine afterwards is

      // wrong.

      if (Tok.getKind() == tok::comment || Tok.getKind() == tok::unknown)

        Callbacks->HandleNewlinesInToken(TokPtr, Len);

      if (Tok.is(tok::comment) && Len >= 2 && TokPtr[0] == '/' &&

          TokPtr[1] == '/') {

        // It's a line comment;

        // Ensure that we don't concatenate anything behind it.

        Callbacks->setEmittedDirectiveOnThisLine();

      }

    } else {

      std::string S = PP.getSpelling(Tok);

      Callbacks->OS->write(S.data(), S.size());

      // Tokens that can contain embedded newlines need to adjust our current

      // line number.

      if (Tok.getKind() == tok::comment || Tok.getKind() == tok::unknown)

        Callbacks->HandleNewlinesInToken(S.data(), S.size());