1 //===--- Rewriter.h - Code rewriting interface ------------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines the Rewriter class, which is used for code
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_CLANG_REWRITER_H
16 #define LLVM_CLANG_REWRITER_H
18 #include "clang/Basic/SourceLocation.h"
19 #include "clang/Rewrite/DeltaTree.h"
20 #include "clang/Rewrite/RewriteRope.h"
21 #include "llvm/ADT/StringRef.h"
27 namespace llvm { class raw_ostream; }
35 /// RewriteBuffer - As code is rewritten, SourceBuffer's from the original
36 /// input with modifications get a new RewriteBuffer associated with them. The
37 /// RewriteBuffer captures the modified text itself as well as information used
38 /// to map between SourceLocation's in the original input and offsets in the
39 /// RewriteBuffer. For example, if text is inserted into the buffer, any
40 /// locations after the insertion point have to be mapped.
42 friend class Rewriter;
43 /// Deltas - Keep track of all the deltas in the source code due to insertions
47 /// Buffer - This is the actual buffer itself. Note that using a vector or
48 /// string is a horribly inefficient way to do this, we should use a rope
50 typedef RewriteRope BufferTy;
53 typedef BufferTy::const_iterator iterator;
54 iterator begin() const { return Buffer.begin(); }
55 iterator end() const { return Buffer.end(); }
56 unsigned size() const { return Buffer.size(); }
58 llvm::raw_ostream &write(llvm::raw_ostream &) const;
60 /// RemoveText - Remove the specified text.
61 void RemoveText(unsigned OrigOffset, unsigned Size);
63 /// InsertText - Insert some text at the specified point, where the offset in
64 /// the buffer is specified relative to the original SourceBuffer. The
65 /// text is inserted after the specified location.
67 void InsertText(unsigned OrigOffset, llvm::StringRef Str,
68 bool InsertAfter = true);
71 /// InsertTextBefore - Insert some text before the specified point, where the
72 /// offset in the buffer is specified relative to the original
73 /// SourceBuffer. The text is inserted before the specified location. This is
74 /// method is the same as InsertText with "InsertAfter == false".
75 void InsertTextBefore(unsigned OrigOffset, llvm::StringRef Str) {
76 InsertText(OrigOffset, Str, false);
79 /// InsertTextAfter - Insert some text at the specified point, where the
80 /// offset in the buffer is specified relative to the original SourceBuffer.
81 /// The text is inserted after the specified location.
82 void InsertTextAfter(unsigned OrigOffset, llvm::StringRef Str) {
83 InsertText(OrigOffset, Str);
86 /// ReplaceText - This method replaces a range of characters in the input
87 /// buffer with a new string. This is effectively a combined "remove/insert"
89 void ReplaceText(unsigned OrigOffset, unsigned OrigLength,
90 llvm::StringRef NewStr);
92 private: // Methods only usable by Rewriter.
94 /// Initialize - Start this rewrite buffer out with a copy of the unmodified
96 void Initialize(const char *BufStart, const char *BufEnd) {
97 Buffer.assign(BufStart, BufEnd);
100 /// getMappedOffset - Given an offset into the original SourceBuffer that this
101 /// RewriteBuffer is based on, map it into the offset space of the
102 /// RewriteBuffer. If AfterInserts is true and if the OrigOffset indicates a
103 /// position where text is inserted, the location returned will be after any
104 /// inserted text at the position.
105 unsigned getMappedOffset(unsigned OrigOffset,
106 bool AfterInserts = false) const{
107 return Deltas.getDeltaAt(2*OrigOffset+AfterInserts)+OrigOffset;
110 /// AddInsertDelta - When an insertion is made at a position, this
111 /// method is used to record that information.
112 void AddInsertDelta(unsigned OrigOffset, int Change) {
113 return Deltas.AddDelta(2*OrigOffset, Change);
116 /// AddReplaceDelta - When a replacement/deletion is made at a position, this
117 /// method is used to record that information.
118 void AddReplaceDelta(unsigned OrigOffset, int Change) {
119 return Deltas.AddDelta(2*OrigOffset+1, Change);
124 /// Rewriter - This is the main interface to the rewrite buffers. Its primary
125 /// job is to dispatch high-level requests to the low-level RewriteBuffers that
128 SourceManager *SourceMgr;
129 const LangOptions *LangOpts;
130 std::map<FileID, RewriteBuffer> RewriteBuffers;
132 typedef std::map<FileID, RewriteBuffer>::iterator buffer_iterator;
134 explicit Rewriter(SourceManager &SM, const LangOptions &LO)
135 : SourceMgr(&SM), LangOpts(&LO) {}
136 explicit Rewriter() : SourceMgr(0), LangOpts(0) {}
138 void setSourceMgr(SourceManager &SM, const LangOptions &LO) {
142 SourceManager &getSourceMgr() { return *SourceMgr; }
143 const LangOptions &getLangOpts() { return *LangOpts; }
145 /// isRewritable - Return true if this location is a raw file location, which
146 /// is rewritable. Locations from macros, etc are not rewritable.
147 static bool isRewritable(SourceLocation Loc) {
148 return Loc.isFileID();
151 /// getRangeSize - Return the size in bytes of the specified range if they
152 /// are in the same file. If not, this returns -1.
153 int getRangeSize(SourceRange Range) const;
154 int getRangeSize(const CharSourceRange &Range) const;
156 /// getRewrittenText - Return the rewritten form of the text in the specified
157 /// range. If the start or end of the range was unrewritable or if they are
158 /// in different buffers, this returns an empty string.
160 /// Note that this method is not particularly efficient.
162 std::string getRewrittenText(SourceRange Range) const;
164 /// InsertText - Insert the specified string at the specified location in the
165 /// original buffer. This method returns true (and does nothing) if the input
166 /// location was not rewritable, false otherwise.
167 bool InsertText(SourceLocation Loc, llvm::StringRef Str,
168 bool InsertAfter = true);
170 /// InsertTextAfter - Insert the specified string at the specified location in
171 /// the original buffer. This method returns true (and does nothing) if
172 /// the input location was not rewritable, false otherwise. Text is
173 /// inserted after any other text that has been previously inserted
174 /// at the some point (the default behavior for InsertText).
175 bool InsertTextAfter(SourceLocation Loc, llvm::StringRef Str) {
176 return InsertText(Loc, Str);
179 /// InsertText - Insert the specified string at the specified location in the
180 /// original buffer. This method returns true (and does nothing) if the input
181 /// location was not rewritable, false otherwise. Text is
182 /// inserted before any other text that has been previously inserted
183 /// at the some point.
184 bool InsertTextBefore(SourceLocation Loc, llvm::StringRef Str) {
185 return InsertText(Loc, Str, false);
188 /// RemoveText - Remove the specified text region.
189 bool RemoveText(SourceLocation Start, unsigned Length);
191 /// ReplaceText - This method replaces a range of characters in the input
192 /// buffer with a new string. This is effectively a combined "remove/insert"
194 bool ReplaceText(SourceLocation Start, unsigned OrigLength,
195 llvm::StringRef NewStr);
197 /// ReplaceStmt - This replaces a Stmt/Expr with another, using the pretty
198 /// printer to generate the replacement code. This returns true if the input
199 /// could not be rewritten, or false if successful.
200 bool ReplaceStmt(Stmt *From, Stmt *To);
202 /// getEditBuffer - This is like getRewriteBufferFor, but always returns a
203 /// buffer, and allows you to write on it directly. This is useful if you
204 /// want efficient low-level access to apis for scribbling on one specific
206 RewriteBuffer &getEditBuffer(FileID FID);
208 /// getRewriteBufferFor - Return the rewrite buffer for the specified FileID.
209 /// If no modification has been made to it, return null.
210 const RewriteBuffer *getRewriteBufferFor(FileID FID) const {
211 std::map<FileID, RewriteBuffer>::const_iterator I =
212 RewriteBuffers.find(FID);
213 return I == RewriteBuffers.end() ? 0 : &I->second;
216 // Iterators over rewrite buffers.
217 buffer_iterator buffer_begin() { return RewriteBuffers.begin(); }
218 buffer_iterator buffer_end() { return RewriteBuffers.end(); }
221 unsigned getLocationOffsetAndFileID(SourceLocation Loc, FileID &FID) const;
224 } // end namespace clang