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RewriteBuffer.h
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1 //===- RewriteBuffer.h - Buffer 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 #ifndef LLVM_CLANG_REWRITE_CORE_REWRITEBUFFER_H
11 #define LLVM_CLANG_REWRITE_CORE_REWRITEBUFFER_H
12 
13 #include "clang/Basic/LLVM.h"
16 #include "llvm/ADT/StringRef.h"
17 
18 namespace clang {
19 
20 /// RewriteBuffer - As code is rewritten, SourceBuffer's from the original
21 /// input with modifications get a new RewriteBuffer associated with them. The
22 /// RewriteBuffer captures the modified text itself as well as information used
23 /// to map between SourceLocation's in the original input and offsets in the
24 /// RewriteBuffer. For example, if text is inserted into the buffer, any
25 /// locations after the insertion point have to be mapped.
27  friend class Rewriter;
28 
29  /// Deltas - Keep track of all the deltas in the source code due to insertions
30  /// and deletions.
31  DeltaTree Deltas;
32 
33  RewriteRope Buffer;
34 
35 public:
37 
38  iterator begin() const { return Buffer.begin(); }
39  iterator end() const { return Buffer.end(); }
40  unsigned size() const { return Buffer.size(); }
41 
42  /// Initialize - Start this rewrite buffer out with a copy of the unmodified
43  /// input buffer.
44  void Initialize(const char *BufStart, const char *BufEnd) {
45  Buffer.assign(BufStart, BufEnd);
46  }
47  void Initialize(StringRef Input) {
48  Initialize(Input.begin(), Input.end());
49  }
50 
51  /// Write to \p Stream the result of applying all changes to the
52  /// original buffer.
53  /// Note that it isn't safe to use this function to overwrite memory mapped
54  /// files in-place (PR17960). Consider using a higher-level utility such as
55  /// Rewriter::overwriteChangedFiles() instead.
56  ///
57  /// The original buffer is not actually changed.
58  raw_ostream &write(raw_ostream &Stream) const;
59 
60  /// RemoveText - Remove the specified text.
61  void RemoveText(unsigned OrigOffset, unsigned Size,
62  bool removeLineIfEmpty = false);
63 
64  /// InsertText - Insert some text at the specified point, where the offset in
65  /// the buffer is specified relative to the original SourceBuffer. The
66  /// text is inserted after the specified location.
67  void InsertText(unsigned OrigOffset, StringRef Str,
68  bool InsertAfter = true);
69 
70 
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, StringRef Str) {
76  InsertText(OrigOffset, Str, false);
77  }
78 
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, StringRef Str) {
83  InsertText(OrigOffset, Str);
84  }
85 
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"
88  /// operation.
89  void ReplaceText(unsigned OrigOffset, unsigned OrigLength,
90  StringRef NewStr);
91 
92 private:
93  /// getMappedOffset - Given an offset into the original SourceBuffer that this
94  /// RewriteBuffer is based on, map it into the offset space of the
95  /// RewriteBuffer. If AfterInserts is true and if the OrigOffset indicates a
96  /// position where text is inserted, the location returned will be after any
97  /// inserted text at the position.
98  unsigned getMappedOffset(unsigned OrigOffset,
99  bool AfterInserts = false) const{
100  return Deltas.getDeltaAt(2*OrigOffset+AfterInserts)+OrigOffset;
101  }
102 
103  /// AddInsertDelta - When an insertion is made at a position, this
104  /// method is used to record that information.
105  void AddInsertDelta(unsigned OrigOffset, int Change) {
106  return Deltas.AddDelta(2*OrigOffset, Change);
107  }
108 
109  /// AddReplaceDelta - When a replacement/deletion is made at a position, this
110  /// method is used to record that information.
111  void AddReplaceDelta(unsigned OrigOffset, int Change) {
112  return Deltas.AddDelta(2*OrigOffset+1, Change);
113  }
114 };
115 
116 } // namespace clang
117 
118 #endif // LLVM_CLANG_REWRITE_CORE_REWRITEBUFFER_H
void AddDelta(unsigned FileIndex, int Delta)
AddDelta - When a change is made that shifts around the text buffer, this method is used to record th...
Definition: DeltaTree.cpp:456
void Initialize(StringRef Input)
Definition: RewriteBuffer.h:47
RewriteRope - A powerful string class.
Definition: RewriteRope.h:167
void Initialize(const char *BufStart, const char *BufEnd)
Initialize - Start this rewrite buffer out with a copy of the unmodified input buffer.
Definition: RewriteBuffer.h:44
RewriteBuffer - As code is rewritten, SourceBuffer's from the original input with modifications get a...
Definition: RewriteBuffer.h:26
iterator end() const
Definition: RewriteBuffer.h:39
RopePieceBTree::iterator const_iterator
Definition: RewriteRope.h:181
Forward-declares and imports various common LLVM datatypes that clang wants to use unqualified...
iterator end() const
Definition: RewriteRope.h:184
iterator begin() const
Definition: RewriteRope.h:183
void InsertTextAfter(unsigned OrigOffset, StringRef Str)
InsertTextAfter - Insert some text at the specified point, where the offset in the buffer is specifie...
Definition: RewriteBuffer.h:82
int getDeltaAt(unsigned FileIndex) const
getDeltaAt - Return the accumulated delta at the specified file offset.
Definition: DeltaTree.cpp:409
void InsertText(unsigned OrigOffset, StringRef Str, bool InsertAfter=true)
InsertText - Insert some text at the specified point, where the offset in the buffer is specified rel...
Definition: Rewriter.cpp:105
iterator begin() const
Definition: RewriteBuffer.h:38
DeltaTree - a multiway search tree (BTree) structure with some fancy features.
Definition: DeltaTree.h:26
void ReplaceText(unsigned OrigOffset, unsigned OrigLength, StringRef NewStr)
ReplaceText - This method replaces a range of characters in the input buffer with a new string...
Definition: Rewriter.cpp:120
raw_ostream & write(raw_ostream &Stream) const
Write to Stream the result of applying all changes to the original buffer.
Definition: Rewriter.cpp:38
unsigned size() const
Definition: RewriteRope.h:185
void RemoveText(unsigned OrigOffset, unsigned Size, bool removeLineIfEmpty=false)
RemoveText - Remove the specified text.
Definition: Rewriter.cpp:62
void InsertTextBefore(unsigned OrigOffset, StringRef Str)
InsertTextBefore - Insert some text before the specified point, where the offset in the buffer is spe...
Definition: RewriteBuffer.h:75
Dataflow Directional Tag Classes.
RopePieceBTreeIterator - This class provides read-only forward iteration over bytes that are in a Rop...
Definition: RewriteRope.h:87
void assign(const char *Start, const char *End)
Definition: RewriteRope.h:191
unsigned size() const
Definition: RewriteBuffer.h:40
Rewriter - This is the main interface to the rewrite buffers.
Definition: Rewriter.h:33