EditedSource.cpp revision 30660a898545416f0fea2d717f16f75640001e38 
1//===----- EditedSource.cpp - Collection of source edits ------------------===//
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#include "clang/Edit/EditedSource.h"
11#include "clang/Edit/Commit.h"
12#include "clang/Edit/EditsReceiver.h"
13#include "clang/Lex/Lexer.h"
14#include "clang/Basic/SourceManager.h"
15#include "llvm/ADT/SmallString.h"
16#include "llvm/ADT/Twine.h"
17
18using namespace clang;
19using namespace edit;
20
21void EditsReceiver::remove(CharSourceRange range) {
22  replace(range, StringRef());
23}
24
25StringRef EditedSource::copyString(const Twine &twine) {
26  llvm::SmallString<128> Data;
27  return copyString(twine.toStringRef(Data));
28}
29
30bool EditedSource::canInsertInOffset(SourceLocation OrigLoc, FileOffset Offs) {
31  FileEditsTy::iterator FA = getActionForOffset(Offs);
32  if (FA != FileEdits.end()) {
33    if (FA->first != Offs)
34      return false; // position has been removed.
35  }
36
37  if (SourceMgr.isMacroArgExpansion(OrigLoc)) {
38    SourceLocation
39      DefArgLoc = SourceMgr.getImmediateExpansionRange(OrigLoc).first;
40    SourceLocation
41      ExpLoc = SourceMgr.getImmediateExpansionRange(DefArgLoc).first;
42    llvm::DenseMap<unsigned, SourceLocation>::iterator
43      I = ExpansionToArgMap.find(ExpLoc.getRawEncoding());
44    if (I != ExpansionToArgMap.end() && I->second != DefArgLoc)
45      return false; // Trying to write in a macro argument input that has
46                 // already been written for another argument of the same macro.
47  }
48
49  return true;
50}
51
52bool EditedSource::commitInsert(SourceLocation OrigLoc,
53                                FileOffset Offs, StringRef text,
54                                bool beforePreviousInsertions) {
55  if (!canInsertInOffset(OrigLoc, Offs))
56    return false;
57  if (text.empty())
58    return true;
59
60  if (SourceMgr.isMacroArgExpansion(OrigLoc)) {
61    SourceLocation
62      DefArgLoc = SourceMgr.getImmediateExpansionRange(OrigLoc).first;
63    SourceLocation
64      ExpLoc = SourceMgr.getImmediateExpansionRange(DefArgLoc).first;
65    ExpansionToArgMap[ExpLoc.getRawEncoding()] = DefArgLoc;
66  }
67
68  FileEdit &FA = FileEdits[Offs];
69  if (FA.Text.empty()) {
70    FA.Text = copyString(text);
71    return true;
72  }
73
74  Twine concat;
75  if (beforePreviousInsertions)
76    concat = Twine(text) + FA.Text;
77  else
78    concat = Twine(FA.Text) +  text;
79
80  FA.Text = copyString(concat);
81  return true;
82}
83
84bool EditedSource::commitInsertFromRange(SourceLocation OrigLoc,
85                                   FileOffset Offs,
86                                   FileOffset InsertFromRangeOffs, unsigned Len,
87                                   bool beforePreviousInsertions) {
88  if (Len == 0)
89    return true;
90
91  llvm::SmallString<128> StrVec;
92  FileOffset BeginOffs = InsertFromRangeOffs;
93  FileOffset EndOffs = BeginOffs.getWithOffset(Len);
94  FileEditsTy::iterator I = FileEdits.upper_bound(BeginOffs);
95  if (I != FileEdits.begin())
96    --I;
97
98  for (; I != FileEdits.end(); ++I) {
99    FileEdit &FA = I->second;
100    FileOffset B = I->first;
101    FileOffset E = B.getWithOffset(FA.RemoveLen);
102
103    if (BeginOffs < E) {
104      if (BeginOffs >= B) {
105        BeginOffs = E;
106        ++I;
107      }
108      break;
109    }
110  }
111
112  for (; I != FileEdits.end() && EndOffs > I->first; ++I) {
113    FileEdit &FA = I->second;
114    FileOffset B = I->first;
115    FileOffset E = B.getWithOffset(FA.RemoveLen);
116
117    if (BeginOffs < B) {
118      bool Invalid = false;
119      StringRef text = getSourceText(BeginOffs, B, Invalid);
120      if (Invalid)
121        return false;
122      StrVec += text;
123    }
124    StrVec += FA.Text;
125    BeginOffs = E;
126  }
127
128  if (BeginOffs < EndOffs) {
129    bool Invalid = false;
130    StringRef text = getSourceText(BeginOffs, EndOffs, Invalid);
131    if (Invalid)
132      return false;
133    StrVec += text;
134  }
135
136  return commitInsert(OrigLoc, Offs, StrVec.str(), beforePreviousInsertions);
137}
138
139void EditedSource::commitRemove(SourceLocation OrigLoc,
140                                FileOffset BeginOffs, unsigned Len) {
141  if (Len == 0)
142    return;
143
144  FileOffset EndOffs = BeginOffs.getWithOffset(Len);
145  FileEditsTy::iterator I = FileEdits.upper_bound(BeginOffs);
146  if (I != FileEdits.begin())
147    --I;
148
149  for (; I != FileEdits.end(); ++I) {
150    FileEdit &FA = I->second;
151    FileOffset B = I->first;
152    FileOffset E = B.getWithOffset(FA.RemoveLen);
153
154    if (BeginOffs < E)
155      break;
156  }
157
158  FileOffset TopBegin, TopEnd;
159  FileEdit *TopFA = 0;
160
161  if (I == FileEdits.end()) {
162    FileEditsTy::iterator
163      NewI = FileEdits.insert(I, std::make_pair(BeginOffs, FileEdit()));
164    NewI->second.RemoveLen = Len;
165    return;
166  }
167
168  FileEdit &FA = I->second;
169  FileOffset B = I->first;
170  FileOffset E = B.getWithOffset(FA.RemoveLen);
171  if (BeginOffs < B) {
172    FileEditsTy::iterator
173      NewI = FileEdits.insert(I, std::make_pair(BeginOffs, FileEdit()));
174    TopBegin = BeginOffs;
175    TopEnd = EndOffs;
176    TopFA = &NewI->second;
177    TopFA->RemoveLen = Len;
178  } else {
179    TopBegin = B;
180    TopEnd = E;
181    TopFA = &I->second;
182    if (TopEnd >= EndOffs)
183      return;
184    unsigned diff = EndOffs.getOffset() - TopEnd.getOffset();
185    TopEnd = EndOffs;
186    TopFA->RemoveLen += diff;
187    ++I;
188  }
189
190  while (I != FileEdits.end()) {
191    FileEdit &FA = I->second;
192    FileOffset B = I->first;
193    FileOffset E = B.getWithOffset(FA.RemoveLen);
194
195    if (B >= TopEnd)
196      break;
197
198    if (E <= TopEnd) {
199      FileEdits.erase(I++);
200      continue;
201    }
202
203    if (B < TopEnd) {
204      unsigned diff = E.getOffset() - TopEnd.getOffset();
205      TopEnd = E;
206      TopFA->RemoveLen += diff;
207      FileEdits.erase(I);
208    }
209
210    break;
211  }
212}
213
214bool EditedSource::commit(const Commit &commit) {
215  if (!commit.isCommitable())
216    return false;
217
218  for (edit::Commit::edit_iterator
219         I = commit.edit_begin(), E = commit.edit_end(); I != E; ++I) {
220    const edit::Commit::Edit &edit = *I;
221    switch (edit.Kind) {
222    case edit::Commit::Act_Insert:
223      commitInsert(edit.OrigLoc, edit.Offset, edit.Text, edit.BeforePrev);
224      break;
225    case edit::Commit::Act_InsertFromRange:
226      commitInsertFromRange(edit.OrigLoc, edit.Offset,
227                            edit.InsertFromRangeOffs, edit.Length,
228                            edit.BeforePrev);
229      break;
230    case edit::Commit::Act_Remove:
231      commitRemove(edit.OrigLoc, edit.Offset, edit.Length);
232      break;
233    }
234  }
235
236  return true;
237}
238
239static void applyRewrite(EditsReceiver &receiver,
240                         StringRef text, FileOffset offs, unsigned len,
241                         const SourceManager &SM) {
242  assert(!offs.getFID().isInvalid());
243  SourceLocation Loc = SM.getLocForStartOfFile(offs.getFID());
244  Loc = Loc.getLocWithOffset(offs.getOffset());
245  assert(Loc.isFileID());
246  CharSourceRange range = CharSourceRange::getCharRange(Loc,
247                                                     Loc.getLocWithOffset(len));
248
249  if (text.empty()) {
250    assert(len);
251    receiver.remove(range);
252    return;
253  }
254
255  if (len)
256    receiver.replace(range, text);
257  else
258    receiver.insert(Loc, text);
259}
260
261void EditedSource::applyRewrites(EditsReceiver &receiver) {
262  llvm::SmallString<128> StrVec;
263  FileOffset CurOffs, CurEnd;
264  unsigned CurLen;
265
266  if (FileEdits.empty())
267    return;
268
269  FileEditsTy::iterator I = FileEdits.begin();
270  CurOffs = I->first;
271  StrVec = I->second.Text;
272  CurLen = I->second.RemoveLen;
273  CurEnd = CurOffs.getWithOffset(CurLen);
274  ++I;
275
276  for (FileEditsTy::iterator E = FileEdits.end(); I != E; ++I) {
277    FileOffset offs = I->first;
278    FileEdit act = I->second;
279    assert(offs >= CurEnd);
280
281    if (offs == CurEnd) {
282      StrVec += act.Text;
283      CurLen += act.RemoveLen;
284      CurEnd.getWithOffset(act.RemoveLen);
285      continue;
286    }
287
288    applyRewrite(receiver, StrVec.str(), CurOffs, CurLen, SourceMgr);
289    CurOffs = offs;
290    StrVec = act.Text;
291    CurLen = act.RemoveLen;
292    CurEnd = CurOffs.getWithOffset(CurLen);
293  }
294
295  applyRewrite(receiver, StrVec.str(), CurOffs, CurLen, SourceMgr);
296}
297
298void EditedSource::clearRewrites() {
299  FileEdits.clear();
300  StrAlloc.Reset();
301}
302
303StringRef EditedSource::getSourceText(FileOffset BeginOffs, FileOffset EndOffs,
304                                      bool &Invalid) {
305  assert(BeginOffs.getFID() == EndOffs.getFID());
306  assert(BeginOffs <= EndOffs);
307  SourceLocation BLoc = SourceMgr.getLocForStartOfFile(BeginOffs.getFID());
308  BLoc = BLoc.getLocWithOffset(BeginOffs.getOffset());
309  assert(BLoc.isFileID());
310  SourceLocation
311    ELoc = BLoc.getLocWithOffset(EndOffs.getOffset() - BeginOffs.getOffset());
312  return Lexer::getSourceText(CharSourceRange::getCharRange(BLoc, ELoc),
313                              SourceMgr, LangOpts, &Invalid);
314}
315
316EditedSource::FileEditsTy::iterator
317EditedSource::getActionForOffset(FileOffset Offs) {
318  FileEditsTy::iterator I = FileEdits.upper_bound(Offs);
319  if (I == FileEdits.begin())
320    return FileEdits.end();
321  --I;
322  FileEdit &FA = I->second;
323  FileOffset B = I->first;
324  FileOffset E = B.getWithOffset(FA.RemoveLen);
325  if (Offs >= B && Offs < E)
326    return I;
327
328  return FileEdits.end();
329}
330