SourceMgr.h revision 321369 
1//===- SourceMgr.h - Manager for Source Buffers & Diagnostics ---*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file declares the SMDiagnostic and SourceMgr classes.  This
11// provides a simple substrate for diagnostics, #include handling, and other low
12// level things for simple parsers.
13//
14//===----------------------------------------------------------------------===//
15
16#ifndef LLVM_SUPPORT_SOURCEMGR_H
17#define LLVM_SUPPORT_SOURCEMGR_H
18
19#include "llvm/ADT/ArrayRef.h"
20#include "llvm/ADT/None.h"
21#include "llvm/ADT/SmallVector.h"
22#include "llvm/ADT/StringRef.h"
23#include "llvm/ADT/Twine.h"
24#include "llvm/Support/MemoryBuffer.h"
25#include "llvm/Support/SMLoc.h"
26#include <algorithm>
27#include <cassert>
28#include <memory>
29#include <string>
30#include <utility>
31#include <vector>
32
33namespace llvm {
34
35class raw_ostream;
36class SMDiagnostic;
37class SMFixIt;
38
39/// This owns the files read by a parser, handles include stacks,
40/// and handles diagnostic wrangling.
41class SourceMgr {
42public:
43  enum DiagKind {
44    DK_Error,
45    DK_Warning,
46    DK_Note
47  };
48
49  /// Clients that want to handle their own diagnostics in a custom way can
50  /// register a function pointer+context as a diagnostic handler.
51  /// It gets called each time PrintMessage is invoked.
52  using DiagHandlerTy = void (*)(const SMDiagnostic &, void *Context);
53
54private:
55  struct SrcBuffer {
56    /// The memory buffer for the file.
57    std::unique_ptr<MemoryBuffer> Buffer;
58
59    /// This is the location of the parent include, or null if at the top level.
60    SMLoc IncludeLoc;
61  };
62
63  /// This is all of the buffers that we are reading from.
64  std::vector<SrcBuffer> Buffers;
65
66  // This is the list of directories we should search for include files in.
67  std::vector<std::string> IncludeDirectories;
68
69  /// This is a cache for line number queries, its implementation is really
70  /// private to SourceMgr.cpp.
71  mutable void *LineNoCache = nullptr;
72
73  DiagHandlerTy DiagHandler = nullptr;
74  void *DiagContext = nullptr;
75
76  bool isValidBufferID(unsigned i) const { return i && i <= Buffers.size(); }
77
78public:
79  SourceMgr() = default;
80  SourceMgr(const SourceMgr &) = delete;
81  SourceMgr &operator=(const SourceMgr &) = delete;
82  ~SourceMgr();
83
84  void setIncludeDirs(const std::vector<std::string> &Dirs) {
85    IncludeDirectories = Dirs;
86  }
87
88  /// Specify a diagnostic handler to be invoked every time PrintMessage is
89  /// called. \p Ctx is passed into the handler when it is invoked.
90  void setDiagHandler(DiagHandlerTy DH, void *Ctx = nullptr) {
91    DiagHandler = DH;
92    DiagContext = Ctx;
93  }
94
95  DiagHandlerTy getDiagHandler() const { return DiagHandler; }
96  void *getDiagContext() const { return DiagContext; }
97
98  const SrcBuffer &getBufferInfo(unsigned i) const {
99    assert(isValidBufferID(i));
100    return Buffers[i - 1];
101  }
102
103  const MemoryBuffer *getMemoryBuffer(unsigned i) const {
104    assert(isValidBufferID(i));
105    return Buffers[i - 1].Buffer.get();
106  }
107
108  unsigned getNumBuffers() const {
109    return Buffers.size();
110  }
111
112  unsigned getMainFileID() const {
113    assert(getNumBuffers());
114    return 1;
115  }
116
117  SMLoc getParentIncludeLoc(unsigned i) const {
118    assert(isValidBufferID(i));
119    return Buffers[i - 1].IncludeLoc;
120  }
121
122  /// Add a new source buffer to this source manager. This takes ownership of
123  /// the memory buffer.
124  unsigned AddNewSourceBuffer(std::unique_ptr<MemoryBuffer> F,
125                              SMLoc IncludeLoc) {
126    SrcBuffer NB;
127    NB.Buffer = std::move(F);
128    NB.IncludeLoc = IncludeLoc;
129    Buffers.push_back(std::move(NB));
130    return Buffers.size();
131  }
132
133  /// Search for a file with the specified name in the current directory or in
134  /// one of the IncludeDirs.
135  ///
136  /// If no file is found, this returns 0, otherwise it returns the buffer ID
137  /// of the stacked file. The full path to the included file can be found in
138  /// \p IncludedFile.
139  unsigned AddIncludeFile(const std::string &Filename, SMLoc IncludeLoc,
140                          std::string &IncludedFile);
141
142  /// Return the ID of the buffer containing the specified location.
143  ///
144  /// 0 is returned if the buffer is not found.
145  unsigned FindBufferContainingLoc(SMLoc Loc) const;
146
147  /// Find the line number for the specified location in the specified file.
148  /// This is not a fast method.
149  unsigned FindLineNumber(SMLoc Loc, unsigned BufferID = 0) const {
150    return getLineAndColumn(Loc, BufferID).first;
151  }
152
153  /// Find the line and column number for the specified location in the
154  /// specified file. This is not a fast method.
155  std::pair<unsigned, unsigned> getLineAndColumn(SMLoc Loc,
156                                                 unsigned BufferID = 0) const;
157
158  /// Emit a message about the specified location with the specified string.
159  ///
160  /// \param ShowColors Display colored messages if output is a terminal and
161  /// the default error handler is used.
162  void PrintMessage(raw_ostream &OS, SMLoc Loc, DiagKind Kind,
163                    const Twine &Msg,
164                    ArrayRef<SMRange> Ranges = None,
165                    ArrayRef<SMFixIt> FixIts = None,
166                    bool ShowColors = true) const;
167
168  /// Emits a diagnostic to llvm::errs().
169  void PrintMessage(SMLoc Loc, DiagKind Kind, const Twine &Msg,
170                    ArrayRef<SMRange> Ranges = None,
171                    ArrayRef<SMFixIt> FixIts = None,
172                    bool ShowColors = true) const;
173
174  /// Emits a manually-constructed diagnostic to the given output stream.
175  ///
176  /// \param ShowColors Display colored messages if output is a terminal and
177  /// the default error handler is used.
178  void PrintMessage(raw_ostream &OS, const SMDiagnostic &Diagnostic,
179                    bool ShowColors = true) const;
180
181  /// Return an SMDiagnostic at the specified location with the specified
182  /// string.
183  ///
184  /// \param Msg If non-null, the kind of message (e.g., "error") which is
185  /// prefixed to the message.
186  SMDiagnostic GetMessage(SMLoc Loc, DiagKind Kind, const Twine &Msg,
187                          ArrayRef<SMRange> Ranges = None,
188                          ArrayRef<SMFixIt> FixIts = None) const;
189
190  /// Prints the names of included files and the line of the file they were
191  /// included from. A diagnostic handler can use this before printing its
192  /// custom formatted message.
193  ///
194  /// \param IncludeLoc The location of the include.
195  /// \param OS the raw_ostream to print on.
196  void PrintIncludeStack(SMLoc IncludeLoc, raw_ostream &OS) const;
197};
198
199/// Represents a single fixit, a replacement of one range of text with another.
200class SMFixIt {
201  SMRange Range;
202
203  std::string Text;
204
205public:
206  // FIXME: Twine.str() is not very efficient.
207  SMFixIt(SMLoc Loc, const Twine &Insertion)
208    : Range(Loc, Loc), Text(Insertion.str()) {
209    assert(Loc.isValid());
210  }
211
212  // FIXME: Twine.str() is not very efficient.
213  SMFixIt(SMRange R, const Twine &Replacement)
214    : Range(R), Text(Replacement.str()) {
215    assert(R.isValid());
216  }
217
218  StringRef getText() const { return Text; }
219  SMRange getRange() const { return Range; }
220
221  bool operator<(const SMFixIt &Other) const {
222    if (Range.Start.getPointer() != Other.Range.Start.getPointer())
223      return Range.Start.getPointer() < Other.Range.Start.getPointer();
224    if (Range.End.getPointer() != Other.Range.End.getPointer())
225      return Range.End.getPointer() < Other.Range.End.getPointer();
226    return Text < Other.Text;
227  }
228};
229
230/// Instances of this class encapsulate one diagnostic report, allowing
231/// printing to a raw_ostream as a caret diagnostic.
232class SMDiagnostic {
233  const SourceMgr *SM = nullptr;
234  SMLoc Loc;
235  std::string Filename;
236  int LineNo = 0;
237  int ColumnNo = 0;
238  SourceMgr::DiagKind Kind = SourceMgr::DK_Error;
239  std::string Message, LineContents;
240  std::vector<std::pair<unsigned, unsigned>> Ranges;
241  SmallVector<SMFixIt, 4> FixIts;
242
243public:
244  // Null diagnostic.
245  SMDiagnostic() = default;
246  // Diagnostic with no location (e.g. file not found, command line arg error).
247  SMDiagnostic(StringRef filename, SourceMgr::DiagKind Knd, StringRef Msg)
248    : Filename(filename), LineNo(-1), ColumnNo(-1), Kind(Knd), Message(Msg) {}
249
250  // Diagnostic with a location.
251  SMDiagnostic(const SourceMgr &sm, SMLoc L, StringRef FN,
252               int Line, int Col, SourceMgr::DiagKind Kind,
253               StringRef Msg, StringRef LineStr,
254               ArrayRef<std::pair<unsigned,unsigned>> Ranges,
255               ArrayRef<SMFixIt> FixIts = None);
256
257  const SourceMgr *getSourceMgr() const { return SM; }
258  SMLoc getLoc() const { return Loc; }
259  StringRef getFilename() const { return Filename; }
260  int getLineNo() const { return LineNo; }
261  int getColumnNo() const { return ColumnNo; }
262  SourceMgr::DiagKind getKind() const { return Kind; }
263  StringRef getMessage() const { return Message; }
264  StringRef getLineContents() const { return LineContents; }
265  ArrayRef<std::pair<unsigned, unsigned>> getRanges() const { return Ranges; }
266
267  void addFixIt(const SMFixIt &Hint) {
268    FixIts.push_back(Hint);
269  }
270
271  ArrayRef<SMFixIt> getFixIts() const {
272    return FixIts;
273  }
274
275  void print(const char *ProgName, raw_ostream &S, bool ShowColors = true,
276             bool ShowKindLabel = true) const;
277};
278
279} // end namespace llvm
280
281#endif // LLVM_SUPPORT_SOURCEMGR_H
282