//===- SourceMgr.h - Manager for Source Buffers & Diagnostics ---*- C++ -*-===//
 
//
 
// 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 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/SmallVector.h"
 
#include "llvm/Support/MemoryBuffer.h"
 
#include "llvm/Support/SMLoc.h"
 
#include <vector>
 
 
 
namespace llvm {
 
 
 
class raw_ostream;
 
class SMDiagnostic;
 
class SMFixIt;
 
 
 
/// 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_Remark,
 
    DK_Note,
 
  };
 
 
 
  /// 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.
 
  using DiagHandlerTy = void (*)(const SMDiagnostic &, void *Context);
 
 
 
private:
 
  struct SrcBuffer {
 
    /// The memory buffer for the file.
 
    std::unique_ptr<MemoryBuffer> Buffer;
 
 
 
    /// Vector of offsets into Buffer at which there are line-endings
 
    /// (lazily populated). Once populated, the '\n' that marks the end of
 
    /// line number N from [1..] is at Buffer[OffsetCache[N-1]]. Since
 
    /// these offsets are in sorted (ascending) order, they can be
 
    /// binary-searched for the first one after any given offset (eg. an
 
    /// offset corresponding to a particular SMLoc).
 
    ///
 
    /// Since we're storing offsets into relatively small files (often smaller
 
    /// than 2^8 or 2^16 bytes), we select the offset vector element type
 
    /// dynamically based on the size of Buffer.
 
    mutable void *OffsetCache = nullptr;
 
 
 
    /// Look up a given \p Ptr in in the buffer, determining which line it came
 
    /// from.
 
    unsigned getLineNumber(const char *Ptr) const;
 
    template <typename T>
 
    unsigned getLineNumberSpecialized(const char *Ptr) const;
 
 
 
    /// Return a pointer to the first character of the specified line number or
 
    /// null if the line number is invalid.
 
    const char *getPointerForLineNumber(unsigned LineNo) const;
 
    template <typename T>
 
    const char *getPointerForLineNumberSpecialized(unsigned LineNo) const;
 
 
 
    /// This is the location of the parent include, or null if at the top level.
 
    SMLoc IncludeLoc;
 
 
 
    SrcBuffer() = default;
 
    SrcBuffer(SrcBuffer &&);
 
    SrcBuffer(const SrcBuffer &) = delete;
 
    SrcBuffer &operator=(const SrcBuffer &) = delete;
 
    ~SrcBuffer();
 
  };
 
 
 
  /// This is all of the buffers that we are reading from.
 
  std::vector<SrcBuffer> Buffers;
 
 
 
  // This is the list of directories we should search for include files in.
 
  std::vector<std::string> IncludeDirectories;
 
 
 
  DiagHandlerTy DiagHandler = nullptr;
 
  void *DiagContext = nullptr;
 
 
 
  bool isValidBufferID(unsigned i) const { return i && i <= Buffers.size(); }
 
 
 
public:
 
  SourceMgr() = default;
 
  SourceMgr(const SourceMgr &) = delete;
 
  SourceMgr &operator=(const SourceMgr &) = delete;
 
  SourceMgr(SourceMgr &&) = default;
 
  SourceMgr &operator=(SourceMgr &&) = default;
 
  ~SourceMgr() = default;
 
 
 
  /// Return the include directories of this source manager.
 
  ArrayRef<std::string> getIncludeDirs() const { return IncludeDirectories; }
 
 
 
  void setIncludeDirs(const std::vector<std::string> &Dirs) {
 
    IncludeDirectories = Dirs;
 
  }
 
 
 
  /// Specify a diagnostic handler to be invoked every time PrintMessage is
 
  /// called. \p Ctx is passed into the handler when it is invoked.
 
  void setDiagHandler(DiagHandlerTy DH, void *Ctx = nullptr) {
 
    DiagHandler = DH;
 
    DiagContext = Ctx;
 
  }
 
 
 
  DiagHandlerTy getDiagHandler() const { return DiagHandler; }
 
  void *getDiagContext() const { return DiagContext; }
 
 
 
  const SrcBuffer &getBufferInfo(unsigned i) const {
 
    assert(isValidBufferID(i));
 
    return Buffers[i - 1];
 
  }
 
 
 
  const MemoryBuffer *getMemoryBuffer(unsigned i) const {
 
    assert(isValidBufferID(i));
 
    return Buffers[i - 1].Buffer.get();
 
  }
 
 
 
  unsigned getNumBuffers() const { return Buffers.size(); }
 
 
 
  unsigned getMainFileID() const {
 
    assert(getNumBuffers());
 
    return 1;
 
  }
 
 
 
  SMLoc getParentIncludeLoc(unsigned i) const {
 
    assert(isValidBufferID(i));
 
    return Buffers[i - 1].IncludeLoc;
 
  }
 
 
 
  /// Add a new source buffer to this source manager. This takes ownership of
 
  /// the memory buffer.
 
  unsigned AddNewSourceBuffer(std::unique_ptr<MemoryBuffer> F,
 
                              SMLoc IncludeLoc) {
 
    SrcBuffer NB;
 
    NB.Buffer = std::move(F);
 
    NB.IncludeLoc = IncludeLoc;
 
    Buffers.push_back(std::move(NB));
 
    return Buffers.size();
 
  }
 
 
 
  /// Takes the source buffers from the given source manager and append them to
 
  /// the current manager. `MainBufferIncludeLoc` is an optional include
 
  /// location to attach to the main buffer of `SrcMgr` after it gets moved to
 
  /// the current manager.
 
  void takeSourceBuffersFrom(SourceMgr &SrcMgr,
 
                             SMLoc MainBufferIncludeLoc = SMLoc()) {
 
    if (SrcMgr.Buffers.empty())
 
      return;
 
 
 
    size_t OldNumBuffers = getNumBuffers();
 
    std::move(SrcMgr.Buffers.begin(), SrcMgr.Buffers.end(),
 
              std::back_inserter(Buffers));
 
    SrcMgr.Buffers.clear();
 
    Buffers[OldNumBuffers].IncludeLoc = MainBufferIncludeLoc;
 
  }
 
 
 
  /// 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
 
  /// \p IncludedFile.
 
  unsigned AddIncludeFile(const std::string &Filename, SMLoc IncludeLoc,
 
                          std::string &IncludedFile);
 
 
 
  /// Search for a file with the specified name in the current directory or in
 
  /// one of the IncludeDirs, and try to open it **without** adding to the
 
  /// SourceMgr. If the opened file is intended to be added to the source
 
  /// manager, prefer `AddIncludeFile` instead.
 
  ///
 
  /// If no file is found, this returns an Error, otherwise it returns the
 
  /// buffer of the stacked file. The full path to the included file can be
 
  /// found in \p IncludedFile.
 
  ErrorOr<std::unique_ptr<MemoryBuffer>>
 
  OpenIncludeFile(const std::string &Filename, std::string &IncludedFile);
 
 
 
  /// Return the ID of the buffer containing the specified location.
 
  ///
 
  /// 0 is returned if the buffer is not found.
 
  unsigned FindBufferContainingLoc(SMLoc Loc) const;
 
 
 
  /// Find the line number for the specified location in the specified file.
 
  /// This is not a fast method.
 
  unsigned FindLineNumber(SMLoc Loc, unsigned BufferID = 0) const {
 
    return getLineAndColumn(Loc, BufferID).first;
 
  }
 
 
 
  /// 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,
 
                                                 unsigned BufferID = 0) const;
 
 
 
  /// Get a string with the \p SMLoc filename and line number
 
  /// formatted in the standard style.
 
  std::string getFormattedLocationNoOffset(SMLoc Loc,
 
                                           bool IncludePath = false) const;
 
 
 
  /// Given a line and column number in a mapped buffer, turn it into an SMLoc.
 
  /// This will return a null SMLoc if the line/column location is invalid.
 
  SMLoc FindLocForLineAndColumn(unsigned BufferID, unsigned LineNo,
 
                                unsigned ColNo);
 
 
 
  /// 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 = {},
 
                    ArrayRef<SMFixIt> FixIts = {},
 
                    bool ShowColors = true) const;
 
 
 
  /// Emits a diagnostic to llvm::errs().
 
  void PrintMessage(SMLoc Loc, DiagKind Kind, const Twine &Msg,
 
                    ArrayRef<SMRange> Ranges = {},
 
                    ArrayRef<SMFixIt> FixIts = {},
 
                    bool ShowColors = true) const;
 
 
 
  /// Emits a manually-constructed diagnostic to the given output stream.
 
  ///
 
  /// \param ShowColors Display colored messages if output is a terminal and
 
  /// the default error handler is used.
 
  void PrintMessage(raw_ostream &OS, const SMDiagnostic &Diagnostic,
 
                    bool ShowColors = true) const;
 
 
 
  /// 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 = {},
 
                          ArrayRef<SMFixIt> FixIts = {}) const;
 
 
 
  /// 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 location 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:
 
  SMFixIt(SMRange R, const Twine &Replacement);
 
 
 
  SMFixIt(SMLoc Loc, const Twine &Replacement)
 
      : SMFixIt(SMRange(Loc, Loc), Replacement) {}
 
 
 
  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;
 
  }
 
};
 
 
 
/// Instances of this class encapsulate one diagnostic report, allowing
 
/// printing to a raw_ostream as a caret diagnostic.
 
class SMDiagnostic {
 
  const SourceMgr *SM = nullptr;
 
  SMLoc Loc;
 
  std::string Filename;
 
  int LineNo = 0;
 
  int ColumnNo = 0;
 
  SourceMgr::DiagKind Kind = SourceMgr::DK_Error;
 
  std::string Message, LineContents;
 
  std::vector<std::pair<unsigned, unsigned>> Ranges;
 
  SmallVector<SMFixIt, 4> FixIts;
 
 
 
public:
 
  // Null diagnostic.
 
  SMDiagnostic() = default;
 
  // Diagnostic with no location (e.g. file not found, command line arg error).
 
  SMDiagnostic(StringRef filename, SourceMgr::DiagKind Knd, StringRef Msg)
 
      : 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 = {});
 
 
 
  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,
 
             bool ShowKindLabel = true) const;
 
};
 
 
 
} // end namespace llvm
 
 
 
#endif // LLVM_SUPPORT_SOURCEMGR_H