1//===--- Rewriter.h - Code rewriting interface ------------------*- 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 defines the Rewriter class, which is used for code
11//  transformations.
12//
13//===----------------------------------------------------------------------===//
14
15#ifndef LLVM_CLANG_REWRITE_CORE_REWRITER_H
16#define LLVM_CLANG_REWRITE_CORE_REWRITER_H
17
18#include "clang/Basic/SourceLocation.h"
19#include "clang/Rewrite/Core/RewriteBuffer.h"
20#include <cstring>
21#include <map>
22#include <string>
23
24namespace clang {
25  class LangOptions;
26  class SourceManager;
27
28/// Rewriter - This is the main interface to the rewrite buffers.  Its primary
29/// job is to dispatch high-level requests to the low-level RewriteBuffers that
30/// are involved.
31class Rewriter {
32  SourceManager *SourceMgr;
33  const LangOptions *LangOpts;
34  std::map<FileID, RewriteBuffer> RewriteBuffers;
35public:
36  struct RewriteOptions {
37    /// \brief Given a source range, true to include previous inserts at the
38    /// beginning of the range as part of the range itself (true by default).
39    bool IncludeInsertsAtBeginOfRange;
40    /// \brief Given a source range, true to include previous inserts at the
41    /// end of the range as part of the range itself (true by default).
42    bool IncludeInsertsAtEndOfRange;
43    /// \brief If true and removing some text leaves a blank line
44    /// also remove the empty line (false by default).
45    bool RemoveLineIfEmpty;
46
47    RewriteOptions()
48      : IncludeInsertsAtBeginOfRange(true),
49        IncludeInsertsAtEndOfRange(true),
50        RemoveLineIfEmpty(false) { }
51  };
52
53  typedef std::map<FileID, RewriteBuffer>::iterator buffer_iterator;
54  typedef std::map<FileID, RewriteBuffer>::const_iterator const_buffer_iterator;
55
56  explicit Rewriter(SourceManager &SM, const LangOptions &LO)
57    : SourceMgr(&SM), LangOpts(&LO) {}
58  explicit Rewriter() : SourceMgr(nullptr), LangOpts(nullptr) {}
59
60  void setSourceMgr(SourceManager &SM, const LangOptions &LO) {
61    SourceMgr = &SM;
62    LangOpts = &LO;
63  }
64  SourceManager &getSourceMgr() const { return *SourceMgr; }
65  const LangOptions &getLangOpts() const { return *LangOpts; }
66
67  /// isRewritable - Return true if this location is a raw file location, which
68  /// is rewritable.  Locations from macros, etc are not rewritable.
69  static bool isRewritable(SourceLocation Loc) {
70    return Loc.isFileID();
71  }
72
73  /// getRangeSize - Return the size in bytes of the specified range if they
74  /// are in the same file.  If not, this returns -1.
75  int getRangeSize(SourceRange Range,
76                   RewriteOptions opts = RewriteOptions()) const;
77  int getRangeSize(const CharSourceRange &Range,
78                   RewriteOptions opts = RewriteOptions()) const;
79
80  /// getRewrittenText - Return the rewritten form of the text in the specified
81  /// range.  If the start or end of the range was unrewritable or if they are
82  /// in different buffers, this returns an empty string.
83  ///
84  /// Note that this method is not particularly efficient.
85  ///
86  std::string getRewrittenText(SourceRange Range) const;
87
88  /// InsertText - Insert the specified string at the specified location in the
89  /// original buffer.  This method returns true (and does nothing) if the input
90  /// location was not rewritable, false otherwise.
91  ///
92  /// \param indentNewLines if true new lines in the string are indented
93  /// using the indentation of the source line in position \p Loc.
94  bool InsertText(SourceLocation Loc, StringRef Str,
95                  bool InsertAfter = true, bool indentNewLines = false);
96
97  /// InsertTextAfter - Insert the specified string at the specified location in
98  ///  the original buffer.  This method returns true (and does nothing) if
99  ///  the input location was not rewritable, false otherwise.  Text is
100  ///  inserted after any other text that has been previously inserted
101  ///  at the some point (the default behavior for InsertText).
102  bool InsertTextAfter(SourceLocation Loc, StringRef Str) {
103    return InsertText(Loc, Str);
104  }
105
106  /// \brief Insert the specified string after the token in the
107  /// specified location.
108  bool InsertTextAfterToken(SourceLocation Loc, StringRef Str);
109
110  /// InsertText - Insert the specified string at the specified location in the
111  /// original buffer.  This method returns true (and does nothing) if the input
112  /// location was not rewritable, false otherwise.  Text is
113  /// inserted before any other text that has been previously inserted
114  /// at the some point.
115  bool InsertTextBefore(SourceLocation Loc, StringRef Str) {
116    return InsertText(Loc, Str, false);
117  }
118
119  /// RemoveText - Remove the specified text region.
120  bool RemoveText(SourceLocation Start, unsigned Length,
121                  RewriteOptions opts = RewriteOptions());
122
123  /// \brief Remove the specified text region.
124  bool RemoveText(CharSourceRange range,
125                  RewriteOptions opts = RewriteOptions()) {
126    return RemoveText(range.getBegin(), getRangeSize(range, opts), opts);
127  }
128
129  /// \brief Remove the specified text region.
130  bool RemoveText(SourceRange range, RewriteOptions opts = RewriteOptions()) {
131    return RemoveText(range.getBegin(), getRangeSize(range, opts), opts);
132  }
133
134  /// ReplaceText - This method replaces a range of characters in the input
135  /// buffer with a new string.  This is effectively a combined "remove/insert"
136  /// operation.
137  bool ReplaceText(SourceLocation Start, unsigned OrigLength,
138                   StringRef NewStr);
139
140  /// ReplaceText - This method replaces a range of characters in the input
141  /// buffer with a new string.  This is effectively a combined "remove/insert"
142  /// operation.
143  bool ReplaceText(SourceRange range, StringRef NewStr) {
144    return ReplaceText(range.getBegin(), getRangeSize(range), NewStr);
145  }
146
147  /// ReplaceText - This method replaces a range of characters in the input
148  /// buffer with a new string.  This is effectively a combined "remove/insert"
149  /// operation.
150  bool ReplaceText(SourceRange range, SourceRange replacementRange);
151
152  /// \brief Increase indentation for the lines between the given source range.
153  /// To determine what the indentation should be, 'parentIndent' is used
154  /// that should be at a source location with an indentation one degree
155  /// lower than the given range.
156  bool IncreaseIndentation(CharSourceRange range, SourceLocation parentIndent);
157  bool IncreaseIndentation(SourceRange range, SourceLocation parentIndent) {
158    return IncreaseIndentation(CharSourceRange::getTokenRange(range),
159                               parentIndent);
160  }
161
162  /// getEditBuffer - This is like getRewriteBufferFor, but always returns a
163  /// buffer, and allows you to write on it directly.  This is useful if you
164  /// want efficient low-level access to apis for scribbling on one specific
165  /// FileID's buffer.
166  RewriteBuffer &getEditBuffer(FileID FID);
167
168  /// getRewriteBufferFor - Return the rewrite buffer for the specified FileID.
169  /// If no modification has been made to it, return null.
170  const RewriteBuffer *getRewriteBufferFor(FileID FID) const {
171    std::map<FileID, RewriteBuffer>::const_iterator I =
172      RewriteBuffers.find(FID);
173    return I == RewriteBuffers.end() ? nullptr : &I->second;
174  }
175
176  // Iterators over rewrite buffers.
177  buffer_iterator buffer_begin() { return RewriteBuffers.begin(); }
178  buffer_iterator buffer_end() { return RewriteBuffers.end(); }
179  const_buffer_iterator buffer_begin() const { return RewriteBuffers.begin(); }
180  const_buffer_iterator buffer_end() const { return RewriteBuffers.end(); }
181
182  /// overwriteChangedFiles - Save all changed files to disk.
183  ///
184  /// Returns true if any files were not saved successfully.
185  /// Outputs diagnostics via the source manager's diagnostic engine
186  /// in case of an error.
187  bool overwriteChangedFiles();
188
189private:
190  unsigned getLocationOffsetAndFileID(SourceLocation Loc, FileID &FID) const;
191};
192
193} // end namespace clang
194
195#endif
196