SourceMgr.h

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//===- SourceMgr.h - Manager for Source Buffers & Diagnostics ---*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file declares the SMDiagnostic and SourceMgr classes.  This
// provides a simple substrate for diagnostics, #include handling, and other low
// level things for simple parsers.
//
//===----------------------------------------------------------------------===//

#ifndef LLVM_SUPPORT_SOURCEMGR_H
#define LLVM_SUPPORT_SOURCEMGR_H

#include "llvm/ADT/ArrayRef.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/Twine.h"
#include "llvm/Support/SMLoc.h"
#include <string>

namespace llvm {
  class MemoryBuffer;
  class SourceMgr;
  class SMDiagnostic;
  class SMFixIt;
  class Twine;
  class raw_ostream;

/// SourceMgr - This owns the files read by a parser, handles include stacks,
/// and handles diagnostic wrangling.
class SourceMgr {
public:
  enum DiagKind {
    DK_Error,
    DK_Warning,
    DK_Note
  };

  /// DiagHandlerTy - Clients that want to handle their own diagnostics in a
  /// custom way can register a function pointer+context as a diagnostic
  /// handler.  It gets called each time PrintMessage is invoked.
  typedef void (*DiagHandlerTy)(const SMDiagnostic &, void *Context);
private:
  struct SrcBuffer {
    /// Buffer - The memory buffer for the file.
    MemoryBuffer *Buffer;

    /// IncludeLoc - This is the location of the parent include, or null if at
    /// the top level.
    SMLoc IncludeLoc;
  };

  /// Buffers - This is all of the buffers that we are reading from.
  std::vector<SrcBuffer> Buffers;

  // IncludeDirectories - This is the list of directories we should search for
  // include files in.
  std::vector<std::string> IncludeDirectories;

  /// LineNoCache - This is a cache for line number queries, its implementation
  /// is really private to SourceMgr.cpp.
  mutable void *LineNoCache;

  DiagHandlerTy DiagHandler;
  void *DiagContext;

  SourceMgr(const SourceMgr&) LLVM_DELETED_FUNCTION;
  void operator=(const SourceMgr&) LLVM_DELETED_FUNCTION;
public:
  SourceMgr() : LineNoCache(0), DiagHandler(0), DiagContext(0) {}
  ~SourceMgr();

  void setIncludeDirs(const std::vector<std::string> &Dirs) {
    IncludeDirectories = Dirs;
  }

  /// setDiagHandler - Specify a diagnostic handler to be invoked every time
  /// PrintMessage is called. Ctx is passed into the handler when it is invoked.
  void setDiagHandler(DiagHandlerTy DH, void *Ctx = 0) {
    DiagHandler = DH;
    DiagContext = Ctx;
  }

  DiagHandlerTy getDiagHandler() const { return DiagHandler; }
  void *getDiagContext() const { return DiagContext; }

  const SrcBuffer &getBufferInfo(unsigned i) const {
    assert(i < Buffers.size() && "Invalid Buffer ID!");
    return Buffers[i];
  }

  const MemoryBuffer *getMemoryBuffer(unsigned i) const {
    assert(i < Buffers.size() && "Invalid Buffer ID!");
    return Buffers[i].Buffer;
  }

  size_t getNumBuffers() const {
    return Buffers.size();
  }

  SMLoc getParentIncludeLoc(unsigned i) const {
    assert(i < Buffers.size() && "Invalid Buffer ID!");
    return Buffers[i].IncludeLoc;
  }

  /// AddNewSourceBuffer - Add a new source buffer to this source manager.  This
  /// takes ownership of the memory buffer.
  size_t AddNewSourceBuffer(MemoryBuffer *F, SMLoc IncludeLoc) {
    SrcBuffer NB;
    NB.Buffer = F;
    NB.IncludeLoc = IncludeLoc;
    Buffers.push_back(NB);
    return Buffers.size() - 1;
  }

  /// AddIncludeFile - Search for a file with the specified name in the current
  /// directory or in one of the IncludeDirs.  If no file is found, this returns
  /// ~0, otherwise it returns the buffer ID of the stacked file.
  /// The full path to the included file can be found in IncludedFile.
  size_t AddIncludeFile(const std::string &Filename, SMLoc IncludeLoc,
                        std::string &IncludedFile);

  /// FindBufferContainingLoc - Return the ID of the buffer containing the
  /// specified location, returning -1 if not found.
  int FindBufferContainingLoc(SMLoc Loc) const;

  /// FindLineNumber - Find the line number for the specified location in the
  /// specified file.  This is not a fast method.
  unsigned FindLineNumber(SMLoc Loc, int BufferID = -1) const {
    return getLineAndColumn(Loc, BufferID).first;
  }

  /// getLineAndColumn - Find the line and column number for the specified
  /// location in the specified file.  This is not a fast method.
  std::pair<unsigned, unsigned>
    getLineAndColumn(SMLoc Loc, int BufferID = -1) const;

  /// PrintMessage - Emit a message about the specified location with the
  /// specified string.
  ///
  /// @param ShowColors - Display colored messages if output is a terminal and
  /// the default error handler is used.
  void PrintMessage(raw_ostream &OS, SMLoc Loc, DiagKind Kind,
                    const Twine &Msg,
                    ArrayRef<SMRange> Ranges = None,
                    ArrayRef<SMFixIt> FixIts = None,
                    bool ShowColors = true) const;

  /// Emits a diagnostic to llvm::errs().
  void PrintMessage(SMLoc Loc, DiagKind Kind, const Twine &Msg,
                    ArrayRef<SMRange> Ranges = None,
                    ArrayRef<SMFixIt> FixIts = None,
                    bool ShowColors = true) const;

  /// GetMessage - Return an SMDiagnostic at the specified location with the
  /// specified string.
  ///
  /// @param Msg If non-null, the kind of message (e.g., "error") which is
  /// prefixed to the message.
  SMDiagnostic GetMessage(SMLoc Loc, DiagKind Kind, const Twine &Msg,
                          ArrayRef<SMRange> Ranges = None,
                          ArrayRef<SMFixIt> FixIts = None) const;

  /// PrintIncludeStack - Prints the names of included files and the line of the
  /// file they were included from.  A diagnostic handler can use this before
  /// printing its custom formatted message.
  ///
  /// @param IncludeLoc - The line of the include.
  /// @param OS the raw_ostream to print on.
  void PrintIncludeStack(SMLoc IncludeLoc, raw_ostream &OS) const;
};


/// Represents a single fixit, a replacement of one range of text with another.
class SMFixIt {
  SMRange Range;

  std::string Text;

public:
  // FIXME: Twine.str() is not very efficient.
  SMFixIt(SMLoc Loc, const Twine &Insertion)
    : Range(Loc, Loc), Text(Insertion.str()) {
    assert(Loc.isValid());
  }

  // FIXME: Twine.str() is not very efficient.
  SMFixIt(SMRange R, const Twine &Replacement)
    : Range(R), Text(Replacement.str()) {
    assert(R.isValid());
  }

  StringRef getText() const { return Text; }
  SMRange getRange() const { return Range; }

  bool operator<(const SMFixIt &Other) const {
    if (Range.Start.getPointer() != Other.Range.Start.getPointer())
      return Range.Start.getPointer() < Other.Range.Start.getPointer();
    if (Range.End.getPointer() != Other.Range.End.getPointer())
      return Range.End.getPointer() < Other.Range.End.getPointer();
    return Text < Other.Text;
  }
};


/// SMDiagnostic - Instances of this class encapsulate one diagnostic report,
/// allowing printing to a raw_ostream as a caret diagnostic.
class SMDiagnostic {
  const SourceMgr *SM;
  SMLoc Loc;
  std::string Filename;
  int LineNo, ColumnNo;
  SourceMgr::DiagKind Kind;
  std::string Message, LineContents;
  std::vector<std::pair<unsigned, unsigned> > Ranges;
  SmallVector<SMFixIt, 4> FixIts;

public:
  // Null diagnostic.
  SMDiagnostic()
    : SM(0), LineNo(0), ColumnNo(0), Kind(SourceMgr::DK_Error) {}
  // Diagnostic with no location (e.g. file not found, command line arg error).
  SMDiagnostic(StringRef filename, SourceMgr::DiagKind Knd, StringRef Msg)
    : SM(0), Filename(filename), LineNo(-1), ColumnNo(-1), Kind(Knd),
      Message(Msg) {}

  // Diagnostic with a location.
  SMDiagnostic(const SourceMgr &sm, SMLoc L, StringRef FN,
               int Line, int Col, SourceMgr::DiagKind Kind,
               StringRef Msg, StringRef LineStr,
               ArrayRef<std::pair<unsigned,unsigned> > Ranges,
               ArrayRef<SMFixIt> FixIts = None);

  const SourceMgr *getSourceMgr() const { return SM; }
  SMLoc getLoc() const { return Loc; }
  StringRef getFilename() const { return Filename; }
  int getLineNo() const { return LineNo; }
  int getColumnNo() const { return ColumnNo; }
  SourceMgr::DiagKind getKind() const { return Kind; }
  StringRef getMessage() const { return Message; }
  StringRef getLineContents() const { return LineContents; }
  ArrayRef<std::pair<unsigned, unsigned> > getRanges() const {
    return Ranges;
  }

  void addFixIt(const SMFixIt &Hint) {
    FixIts.push_back(Hint);
  }

  ArrayRef<SMFixIt> getFixIts() const {
    return FixIts;
  }

  void print(const char *ProgName, raw_ostream &S,
             bool ShowColors = true) const;
};

}  // end llvm namespace

#endif