1//===- SourceMgr.h - Manager for Source Buffers & Diagnostics ---*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file declares the SMDiagnostic and SourceMgr classes. This
10// provides a simple substrate for diagnostics, #include handling, and other low
11// level things for simple parsers.
12//
13//===----------------------------------------------------------------------===//
14
15#ifndef LLVM_SUPPORT_SOURCEMGR_H
16#define LLVM_SUPPORT_SOURCEMGR_H
17
18#include "llvm/ADT/SmallVector.h"
19#include "llvm/Support/MemoryBuffer.h"
20#include "llvm/Support/SMLoc.h"
21#include <vector>
22
23namespace llvm {
24
25class raw_ostream;
26class SMDiagnostic;
27class SMFixIt;
28
29/// This owns the files read by a parser, handles include stacks,
30/// and handles diagnostic wrangling.
31class SourceMgr {
32public:
33 enum DiagKind {
34 DK_Error,
35 DK_Warning,
36 DK_Remark,
37 DK_Note,
38 };
39
40 /// Clients that want to handle their own diagnostics in a custom way can
41 /// register a function pointer+context as a diagnostic handler.
42 /// It gets called each time PrintMessage is invoked.
43 using DiagHandlerTy = void (*)(const SMDiagnostic &, void *Context);
44
45private:
46 struct SrcBuffer {
47 /// The memory buffer for the file.
48 std::unique_ptr<MemoryBuffer> Buffer;
49
50 /// Vector of offsets into Buffer at which there are line-endings
51 /// (lazily populated). Once populated, the '\n' that marks the end of
52 /// line number N from [1..] is at Buffer[OffsetCache[N-1]]. Since
53 /// these offsets are in sorted (ascending) order, they can be
54 /// binary-searched for the first one after any given offset (eg. an
55 /// offset corresponding to a particular SMLoc).
56 ///
57 /// Since we're storing offsets into relatively small files (often smaller
58 /// than 2^8 or 2^16 bytes), we select the offset vector element type
59 /// dynamically based on the size of Buffer.
60 mutable void *OffsetCache = nullptr;
61
62 /// Look up a given \p Ptr in the buffer, determining which line it came
63 /// from.
64 unsigned getLineNumber(const char *Ptr) const;
65 template <typename T>
66 unsigned getLineNumberSpecialized(const char *Ptr) const;
67
68 /// Return a pointer to the first character of the specified line number or
69 /// null if the line number is invalid.
70 const char *getPointerForLineNumber(unsigned LineNo) const;
71 template <typename T>
72 const char *getPointerForLineNumberSpecialized(unsigned LineNo) const;
73
74 /// This is the location of the parent include, or null if at the top level.
75 SMLoc IncludeLoc;
76
77 SrcBuffer() = default;
78 SrcBuffer(SrcBuffer &&);
79 SrcBuffer(const SrcBuffer &) = delete;
80 SrcBuffer &operator=(const SrcBuffer &) = delete;
81 ~SrcBuffer();
82 };
83
84 /// This is all of the buffers that we are reading from.
85 std::vector<SrcBuffer> Buffers;
86
87 // This is the list of directories we should search for include files in.
88 std::vector<std::string> IncludeDirectories;
89
90 DiagHandlerTy DiagHandler = nullptr;
91 void *DiagContext = nullptr;
92
93 bool isValidBufferID(unsigned i) const { return i && i <= Buffers.size(); }
94
95public:
96 SourceMgr() = default;
97 SourceMgr(const SourceMgr &) = delete;
98 SourceMgr &operator=(const SourceMgr &) = delete;
99 SourceMgr(SourceMgr &&) = default;
100 SourceMgr &operator=(SourceMgr &&) = default;
101 ~SourceMgr() = default;
102
103 /// Return the include directories of this source manager.
104 ArrayRef<std::string> getIncludeDirs() const { return IncludeDirectories; }
105
106 void setIncludeDirs(const std::vector<std::string> &Dirs) {
107 IncludeDirectories = Dirs;
108 }
109
110 /// Specify a diagnostic handler to be invoked every time PrintMessage is
111 /// called. \p Ctx is passed into the handler when it is invoked.
112 void setDiagHandler(DiagHandlerTy DH, void *Ctx = nullptr) {
113 DiagHandler = DH;
114 DiagContext = Ctx;
115 }
116
117 DiagHandlerTy getDiagHandler() const { return DiagHandler; }
118 void *getDiagContext() const { return DiagContext; }
119
120 const SrcBuffer &getBufferInfo(unsigned i) const {
121 assert(isValidBufferID(i));
122 return Buffers[i - 1];
123 }
124
125 const MemoryBuffer *getMemoryBuffer(unsigned i) const {
126 assert(isValidBufferID(i));
127 return Buffers[i - 1].Buffer.get();
128 }
129
130 unsigned getNumBuffers() const { return Buffers.size(); }
131
132 unsigned getMainFileID() const {
133 assert(getNumBuffers());
134 return 1;
135 }
136
137 SMLoc getParentIncludeLoc(unsigned i) const {
138 assert(isValidBufferID(i));
139 return Buffers[i - 1].IncludeLoc;
140 }
141
142 /// Add a new source buffer to this source manager. This takes ownership of
143 /// the memory buffer.
144 unsigned AddNewSourceBuffer(std::unique_ptr<MemoryBuffer> F,
145 SMLoc IncludeLoc) {
146 SrcBuffer NB;
147 NB.Buffer = std::move(F);
148 NB.IncludeLoc = IncludeLoc;
149 Buffers.push_back(x: std::move(NB));
150 return Buffers.size();
151 }
152
153 /// Takes the source buffers from the given source manager and append them to
154 /// the current manager. `MainBufferIncludeLoc` is an optional include
155 /// location to attach to the main buffer of `SrcMgr` after it gets moved to
156 /// the current manager.
157 void takeSourceBuffersFrom(SourceMgr &SrcMgr,
158 SMLoc MainBufferIncludeLoc = SMLoc()) {
159 if (SrcMgr.Buffers.empty())
160 return;
161
162 size_t OldNumBuffers = getNumBuffers();
163 std::move(first: SrcMgr.Buffers.begin(), last: SrcMgr.Buffers.end(),
164 result: std::back_inserter(x&: Buffers));
165 SrcMgr.Buffers.clear();
166 Buffers[OldNumBuffers].IncludeLoc = MainBufferIncludeLoc;
167 }
168
169 /// Search for a file with the specified name in the current directory or in
170 /// one of the IncludeDirs.
171 ///
172 /// If no file is found, this returns 0, otherwise it returns the buffer ID
173 /// of the stacked file. The full path to the included file can be found in
174 /// \p IncludedFile.
175 unsigned AddIncludeFile(const std::string &Filename, SMLoc IncludeLoc,
176 std::string &IncludedFile);
177
178 /// Search for a file with the specified name in the current directory or in
179 /// one of the IncludeDirs, and try to open it **without** adding to the
180 /// SourceMgr. If the opened file is intended to be added to the source
181 /// manager, prefer `AddIncludeFile` instead.
182 ///
183 /// If no file is found, this returns an Error, otherwise it returns the
184 /// buffer of the stacked file. The full path to the included file can be
185 /// found in \p IncludedFile.
186 ErrorOr<std::unique_ptr<MemoryBuffer>>
187 OpenIncludeFile(const std::string &Filename, std::string &IncludedFile);
188
189 /// Return the ID of the buffer containing the specified location.
190 ///
191 /// 0 is returned if the buffer is not found.
192 unsigned FindBufferContainingLoc(SMLoc Loc) const;
193
194 /// Find the line number for the specified location in the specified file.
195 /// This is not a fast method.
196 unsigned FindLineNumber(SMLoc Loc, unsigned BufferID = 0) const {
197 return getLineAndColumn(Loc, BufferID).first;
198 }
199
200 /// Find the line and column number for the specified location in the
201 /// specified file. This is not a fast method.
202 std::pair<unsigned, unsigned> getLineAndColumn(SMLoc Loc,
203 unsigned BufferID = 0) const;
204
205 /// Get a string with the \p SMLoc filename and line number
206 /// formatted in the standard style.
207 std::string getFormattedLocationNoOffset(SMLoc Loc,
208 bool IncludePath = false) const;
209
210 /// Given a line and column number in a mapped buffer, turn it into an SMLoc.
211 /// This will return a null SMLoc if the line/column location is invalid.
212 SMLoc FindLocForLineAndColumn(unsigned BufferID, unsigned LineNo,
213 unsigned ColNo);
214
215 /// Emit a message about the specified location with the specified string.
216 ///
217 /// \param ShowColors Display colored messages if output is a terminal and
218 /// the default error handler is used.
219 void PrintMessage(raw_ostream &OS, SMLoc Loc, DiagKind Kind, const Twine &Msg,
220 ArrayRef<SMRange> Ranges = {},
221 ArrayRef<SMFixIt> FixIts = {},
222 bool ShowColors = true) const;
223
224 /// Emits a diagnostic to llvm::errs().
225 void PrintMessage(SMLoc Loc, DiagKind Kind, const Twine &Msg,
226 ArrayRef<SMRange> Ranges = {},
227 ArrayRef<SMFixIt> FixIts = {},
228 bool ShowColors = true) const;
229
230 /// Emits a manually-constructed diagnostic to the given output stream.
231 ///
232 /// \param ShowColors Display colored messages if output is a terminal and
233 /// the default error handler is used.
234 void PrintMessage(raw_ostream &OS, const SMDiagnostic &Diagnostic,
235 bool ShowColors = true) const;
236
237 /// Return an SMDiagnostic at the specified location with the specified
238 /// string.
239 ///
240 /// \param Msg If non-null, the kind of message (e.g., "error") which is
241 /// prefixed to the message.
242 SMDiagnostic GetMessage(SMLoc Loc, DiagKind Kind, const Twine &Msg,
243 ArrayRef<SMRange> Ranges = {},
244 ArrayRef<SMFixIt> FixIts = {}) const;
245
246 /// Prints the names of included files and the line of the file they were
247 /// included from. A diagnostic handler can use this before printing its
248 /// custom formatted message.
249 ///
250 /// \param IncludeLoc The location of the include.
251 /// \param OS the raw_ostream to print on.
252 void PrintIncludeStack(SMLoc IncludeLoc, raw_ostream &OS) const;
253};
254
255/// Represents a single fixit, a replacement of one range of text with another.
256class SMFixIt {
257 SMRange Range;
258
259 std::string Text;
260
261public:
262 SMFixIt(SMRange R, const Twine &Replacement);
263
264 SMFixIt(SMLoc Loc, const Twine &Replacement)
265 : SMFixIt(SMRange(Loc, Loc), Replacement) {}
266
267 StringRef getText() const { return Text; }
268 SMRange getRange() const { return Range; }
269
270 bool operator<(const SMFixIt &Other) const {
271 if (Range.Start.getPointer() != Other.Range.Start.getPointer())
272 return Range.Start.getPointer() < Other.Range.Start.getPointer();
273 if (Range.End.getPointer() != Other.Range.End.getPointer())
274 return Range.End.getPointer() < Other.Range.End.getPointer();
275 return Text < Other.Text;
276 }
277};
278
279/// Instances of this class encapsulate one diagnostic report, allowing
280/// printing to a raw_ostream as a caret diagnostic.
281class SMDiagnostic {
282 const SourceMgr *SM = nullptr;
283 SMLoc Loc;
284 std::string Filename;
285 int LineNo = 0;
286 int ColumnNo = 0;
287 SourceMgr::DiagKind Kind = SourceMgr::DK_Error;
288 std::string Message, LineContents;
289 std::vector<std::pair<unsigned, unsigned>> Ranges;
290 SmallVector<SMFixIt, 4> FixIts;
291
292public:
293 // Null diagnostic.
294 SMDiagnostic() = default;
295 // Diagnostic with no location (e.g. file not found, command line arg error).
296 SMDiagnostic(StringRef filename, SourceMgr::DiagKind Knd, StringRef Msg)
297 : Filename(filename), LineNo(-1), ColumnNo(-1), Kind(Knd), Message(Msg) {}
298
299 // Diagnostic with a location.
300 SMDiagnostic(const SourceMgr &sm, SMLoc L, StringRef FN, int Line, int Col,
301 SourceMgr::DiagKind Kind, StringRef Msg, StringRef LineStr,
302 ArrayRef<std::pair<unsigned, unsigned>> Ranges,
303 ArrayRef<SMFixIt> FixIts = {});
304
305 const SourceMgr *getSourceMgr() const { return SM; }
306 SMLoc getLoc() const { return Loc; }
307 StringRef getFilename() const { return Filename; }
308 int getLineNo() const { return LineNo; }
309 int getColumnNo() const { return ColumnNo; }
310 SourceMgr::DiagKind getKind() const { return Kind; }
311 StringRef getMessage() const { return Message; }
312 StringRef getLineContents() const { return LineContents; }
313 ArrayRef<std::pair<unsigned, unsigned>> getRanges() const { return Ranges; }
314
315 void addFixIt(const SMFixIt &Hint) { FixIts.push_back(Elt: Hint); }
316
317 ArrayRef<SMFixIt> getFixIts() const { return FixIts; }
318
319 void print(const char *ProgName, raw_ostream &S, bool ShowColors = true,
320 bool ShowKindLabel = true, bool ShowLocation = true) const;
321};
322
323} // end namespace llvm
324
325#endif // LLVM_SUPPORT_SOURCEMGR_H
326