clang  6.0.0svn
CommentLexer.cpp
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1 //===--- CommentLexer.cpp -------------------------------------------------===//
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/AST/CommentLexer.h"
13 #include "clang/Basic/CharInfo.h"
14 #include "llvm/ADT/StringExtras.h"
15 #include "llvm/ADT/StringSwitch.h"
16 #include "llvm/Support/ConvertUTF.h"
17 #include "llvm/Support/ErrorHandling.h"
18 
19 namespace clang {
20 namespace comments {
21 
22 void Token::dump(const Lexer &L, const SourceManager &SM) const {
23  llvm::errs() << "comments::Token Kind=" << Kind << " ";
24  Loc.dump(SM);
25  llvm::errs() << " " << Length << " \"" << L.getSpelling(*this, SM) << "\"\n";
26 }
27 
28 static inline bool isHTMLNamedCharacterReferenceCharacter(char C) {
29  return isLetter(C);
30 }
31 
32 static inline bool isHTMLDecimalCharacterReferenceCharacter(char C) {
33  return isDigit(C);
34 }
35 
36 static inline bool isHTMLHexCharacterReferenceCharacter(char C) {
37  return isHexDigit(C);
38 }
39 
40 static inline StringRef convertCodePointToUTF8(
41  llvm::BumpPtrAllocator &Allocator,
42  unsigned CodePoint) {
43  char *Resolved = Allocator.Allocate<char>(UNI_MAX_UTF8_BYTES_PER_CODE_POINT);
44  char *ResolvedPtr = Resolved;
45  if (llvm::ConvertCodePointToUTF8(CodePoint, ResolvedPtr))
46  return StringRef(Resolved, ResolvedPtr - Resolved);
47  else
48  return StringRef();
49 }
50 
51 namespace {
52 
53 #include "clang/AST/CommentHTMLTags.inc"
54 #include "clang/AST/CommentHTMLNamedCharacterReferences.inc"
55 
56 } // end anonymous namespace
57 
58 StringRef Lexer::resolveHTMLNamedCharacterReference(StringRef Name) const {
59  // Fast path, first check a few most widely used named character references.
60  return llvm::StringSwitch<StringRef>(Name)
61  .Case("amp", "&")
62  .Case("lt", "<")
63  .Case("gt", ">")
64  .Case("quot", "\"")
65  .Case("apos", "\'")
66  // Slow path.
67  .Default(translateHTMLNamedCharacterReferenceToUTF8(Name));
68 }
69 
70 StringRef Lexer::resolveHTMLDecimalCharacterReference(StringRef Name) const {
71  unsigned CodePoint = 0;
72  for (unsigned i = 0, e = Name.size(); i != e; ++i) {
74  CodePoint *= 10;
75  CodePoint += Name[i] - '0';
76  }
77  return convertCodePointToUTF8(Allocator, CodePoint);
78 }
79 
80 StringRef Lexer::resolveHTMLHexCharacterReference(StringRef Name) const {
81  unsigned CodePoint = 0;
82  for (unsigned i = 0, e = Name.size(); i != e; ++i) {
83  CodePoint *= 16;
84  const char C = Name[i];
86  CodePoint += llvm::hexDigitValue(C);
87  }
88  return convertCodePointToUTF8(Allocator, CodePoint);
89 }
90 
91 void Lexer::skipLineStartingDecorations() {
92  // This function should be called only for C comments
93  assert(CommentState == LCS_InsideCComment);
94 
95  if (BufferPtr == CommentEnd)
96  return;
97 
98  switch (*BufferPtr) {
99  case ' ':
100  case '\t':
101  case '\f':
102  case '\v': {
103  const char *NewBufferPtr = BufferPtr;
104  NewBufferPtr++;
105  if (NewBufferPtr == CommentEnd)
106  return;
107 
108  char C = *NewBufferPtr;
109  while (isHorizontalWhitespace(C)) {
110  NewBufferPtr++;
111  if (NewBufferPtr == CommentEnd)
112  return;
113  C = *NewBufferPtr;
114  }
115  if (C == '*')
116  BufferPtr = NewBufferPtr + 1;
117  break;
118  }
119  case '*':
120  BufferPtr++;
121  break;
122  }
123 }
124 
125 namespace {
126 /// Returns pointer to the first newline character in the string.
127 const char *findNewline(const char *BufferPtr, const char *BufferEnd) {
128  for ( ; BufferPtr != BufferEnd; ++BufferPtr) {
129  if (isVerticalWhitespace(*BufferPtr))
130  return BufferPtr;
131  }
132  return BufferEnd;
133 }
134 
135 const char *skipNewline(const char *BufferPtr, const char *BufferEnd) {
136  if (BufferPtr == BufferEnd)
137  return BufferPtr;
138 
139  if (*BufferPtr == '\n')
140  BufferPtr++;
141  else {
142  assert(*BufferPtr == '\r');
143  BufferPtr++;
144  if (BufferPtr != BufferEnd && *BufferPtr == '\n')
145  BufferPtr++;
146  }
147  return BufferPtr;
148 }
149 
150 const char *skipNamedCharacterReference(const char *BufferPtr,
151  const char *BufferEnd) {
152  for ( ; BufferPtr != BufferEnd; ++BufferPtr) {
154  return BufferPtr;
155  }
156  return BufferEnd;
157 }
158 
159 const char *skipDecimalCharacterReference(const char *BufferPtr,
160  const char *BufferEnd) {
161  for ( ; BufferPtr != BufferEnd; ++BufferPtr) {
163  return BufferPtr;
164  }
165  return BufferEnd;
166 }
167 
168 const char *skipHexCharacterReference(const char *BufferPtr,
169  const char *BufferEnd) {
170  for ( ; BufferPtr != BufferEnd; ++BufferPtr) {
171  if (!isHTMLHexCharacterReferenceCharacter(*BufferPtr))
172  return BufferPtr;
173  }
174  return BufferEnd;
175 }
176 
177 bool isHTMLIdentifierStartingCharacter(char C) {
178  return isLetter(C);
179 }
180 
181 bool isHTMLIdentifierCharacter(char C) {
182  return isAlphanumeric(C);
183 }
184 
185 const char *skipHTMLIdentifier(const char *BufferPtr, const char *BufferEnd) {
186  for ( ; BufferPtr != BufferEnd; ++BufferPtr) {
187  if (!isHTMLIdentifierCharacter(*BufferPtr))
188  return BufferPtr;
189  }
190  return BufferEnd;
191 }
192 
193 /// Skip HTML string quoted in single or double quotes. Escaping quotes inside
194 /// string allowed.
195 ///
196 /// Returns pointer to closing quote.
197 const char *skipHTMLQuotedString(const char *BufferPtr, const char *BufferEnd)
198 {
199  const char Quote = *BufferPtr;
200  assert(Quote == '\"' || Quote == '\'');
201 
202  BufferPtr++;
203  for ( ; BufferPtr != BufferEnd; ++BufferPtr) {
204  const char C = *BufferPtr;
205  if (C == Quote && BufferPtr[-1] != '\\')
206  return BufferPtr;
207  }
208  return BufferEnd;
209 }
210 
211 const char *skipWhitespace(const char *BufferPtr, const char *BufferEnd) {
212  for ( ; BufferPtr != BufferEnd; ++BufferPtr) {
213  if (!isWhitespace(*BufferPtr))
214  return BufferPtr;
215  }
216  return BufferEnd;
217 }
218 
219 bool isWhitespace(const char *BufferPtr, const char *BufferEnd) {
220  return skipWhitespace(BufferPtr, BufferEnd) == BufferEnd;
221 }
222 
223 bool isCommandNameStartCharacter(char C) {
224  return isLetter(C);
225 }
226 
227 bool isCommandNameCharacter(char C) {
228  return isAlphanumeric(C);
229 }
230 
231 const char *skipCommandName(const char *BufferPtr, const char *BufferEnd) {
232  for ( ; BufferPtr != BufferEnd; ++BufferPtr) {
233  if (!isCommandNameCharacter(*BufferPtr))
234  return BufferPtr;
235  }
236  return BufferEnd;
237 }
238 
239 /// Return the one past end pointer for BCPL comments.
240 /// Handles newlines escaped with backslash or trigraph for backslahs.
241 const char *findBCPLCommentEnd(const char *BufferPtr, const char *BufferEnd) {
242  const char *CurPtr = BufferPtr;
243  while (CurPtr != BufferEnd) {
244  while (!isVerticalWhitespace(*CurPtr)) {
245  CurPtr++;
246  if (CurPtr == BufferEnd)
247  return BufferEnd;
248  }
249  // We found a newline, check if it is escaped.
250  const char *EscapePtr = CurPtr - 1;
251  while(isHorizontalWhitespace(*EscapePtr))
252  EscapePtr--;
253 
254  if (*EscapePtr == '\\' ||
255  (EscapePtr - 2 >= BufferPtr && EscapePtr[0] == '/' &&
256  EscapePtr[-1] == '?' && EscapePtr[-2] == '?')) {
257  // We found an escaped newline.
258  CurPtr = skipNewline(CurPtr, BufferEnd);
259  } else
260  return CurPtr; // Not an escaped newline.
261  }
262  return BufferEnd;
263 }
264 
265 /// Return the one past end pointer for C comments.
266 /// Very dumb, does not handle escaped newlines or trigraphs.
267 const char *findCCommentEnd(const char *BufferPtr, const char *BufferEnd) {
268  for ( ; BufferPtr != BufferEnd; ++BufferPtr) {
269  if (*BufferPtr == '*') {
270  assert(BufferPtr + 1 != BufferEnd);
271  if (*(BufferPtr + 1) == '/')
272  return BufferPtr;
273  }
274  }
275  llvm_unreachable("buffer end hit before '*/' was seen");
276 }
277 
278 } // end anonymous namespace
279 
280 void Lexer::formTokenWithChars(Token &Result, const char *TokEnd,
282  const unsigned TokLen = TokEnd - BufferPtr;
283  Result.setLocation(getSourceLocation(BufferPtr));
284  Result.setKind(Kind);
285  Result.setLength(TokLen);
286 #ifndef NDEBUG
287  Result.TextPtr = "<UNSET>";
288  Result.IntVal = 7;
289 #endif
290  BufferPtr = TokEnd;
291 }
292 
293 void Lexer::lexCommentText(Token &T) {
294  assert(CommentState == LCS_InsideBCPLComment ||
295  CommentState == LCS_InsideCComment);
296 
297  switch (State) {
298  case LS_Normal:
299  break;
300  case LS_VerbatimBlockFirstLine:
301  lexVerbatimBlockFirstLine(T);
302  return;
303  case LS_VerbatimBlockBody:
304  lexVerbatimBlockBody(T);
305  return;
306  case LS_VerbatimLineText:
307  lexVerbatimLineText(T);
308  return;
309  case LS_HTMLStartTag:
310  lexHTMLStartTag(T);
311  return;
312  case LS_HTMLEndTag:
313  lexHTMLEndTag(T);
314  return;
315  }
316 
317  assert(State == LS_Normal);
318 
319  const char *TokenPtr = BufferPtr;
320  assert(TokenPtr < CommentEnd);
321  while (TokenPtr != CommentEnd) {
322  switch(*TokenPtr) {
323  case '\\':
324  case '@': {
325  // Commands that start with a backslash and commands that start with
326  // 'at' have equivalent semantics. But we keep information about the
327  // exact syntax in AST for comments.
328  tok::TokenKind CommandKind =
329  (*TokenPtr == '@') ? tok::at_command : tok::backslash_command;
330  TokenPtr++;
331  if (TokenPtr == CommentEnd) {
332  formTextToken(T, TokenPtr);
333  return;
334  }
335  char C = *TokenPtr;
336  switch (C) {
337  default:
338  break;
339 
340  case '\\': case '@': case '&': case '$':
341  case '#': case '<': case '>': case '%':
342  case '\"': case '.': case ':':
343  // This is one of \\ \@ \& \$ etc escape sequences.
344  TokenPtr++;
345  if (C == ':' && TokenPtr != CommentEnd && *TokenPtr == ':') {
346  // This is the \:: escape sequence.
347  TokenPtr++;
348  }
349  StringRef UnescapedText(BufferPtr + 1, TokenPtr - (BufferPtr + 1));
350  formTokenWithChars(T, TokenPtr, tok::text);
351  T.setText(UnescapedText);
352  return;
353  }
354 
355  // Don't make zero-length commands.
356  if (!isCommandNameStartCharacter(*TokenPtr)) {
357  formTextToken(T, TokenPtr);
358  return;
359  }
360 
361  TokenPtr = skipCommandName(TokenPtr, CommentEnd);
362  unsigned Length = TokenPtr - (BufferPtr + 1);
363 
364  // Hardcoded support for lexing LaTeX formula commands
365  // \f$ \f[ \f] \f{ \f} as a single command.
366  if (Length == 1 && TokenPtr[-1] == 'f' && TokenPtr != CommentEnd) {
367  C = *TokenPtr;
368  if (C == '$' || C == '[' || C == ']' || C == '{' || C == '}') {
369  TokenPtr++;
370  Length++;
371  }
372  }
373 
374  StringRef CommandName(BufferPtr + 1, Length);
375 
376  const CommandInfo *Info = Traits.getCommandInfoOrNULL(CommandName);
377  if (!Info) {
378  if ((Info = Traits.getTypoCorrectCommandInfo(CommandName))) {
379  StringRef CorrectedName = Info->Name;
380  SourceLocation Loc = getSourceLocation(BufferPtr);
381  SourceLocation EndLoc = getSourceLocation(TokenPtr);
382  SourceRange FullRange = SourceRange(Loc, EndLoc);
383  SourceRange CommandRange(Loc.getLocWithOffset(1), EndLoc);
384  Diag(Loc, diag::warn_correct_comment_command_name)
385  << FullRange << CommandName << CorrectedName
386  << FixItHint::CreateReplacement(CommandRange, CorrectedName);
387  } else {
388  formTokenWithChars(T, TokenPtr, tok::unknown_command);
389  T.setUnknownCommandName(CommandName);
390  Diag(T.getLocation(), diag::warn_unknown_comment_command_name)
392  return;
393  }
394  }
395  if (Info->IsVerbatimBlockCommand) {
396  setupAndLexVerbatimBlock(T, TokenPtr, *BufferPtr, Info);
397  return;
398  }
399  if (Info->IsVerbatimLineCommand) {
400  setupAndLexVerbatimLine(T, TokenPtr, Info);
401  return;
402  }
403  formTokenWithChars(T, TokenPtr, CommandKind);
404  T.setCommandID(Info->getID());
405  return;
406  }
407 
408  case '&':
409  lexHTMLCharacterReference(T);
410  return;
411 
412  case '<': {
413  TokenPtr++;
414  if (TokenPtr == CommentEnd) {
415  formTextToken(T, TokenPtr);
416  return;
417  }
418  const char C = *TokenPtr;
419  if (isHTMLIdentifierStartingCharacter(C))
420  setupAndLexHTMLStartTag(T);
421  else if (C == '/')
422  setupAndLexHTMLEndTag(T);
423  else
424  formTextToken(T, TokenPtr);
425  return;
426  }
427 
428  case '\n':
429  case '\r':
430  TokenPtr = skipNewline(TokenPtr, CommentEnd);
431  formTokenWithChars(T, TokenPtr, tok::newline);
432 
433  if (CommentState == LCS_InsideCComment)
434  skipLineStartingDecorations();
435  return;
436 
437  default: {
438  size_t End = StringRef(TokenPtr, CommentEnd - TokenPtr).
439  find_first_of("\n\r\\@&<");
440  if (End != StringRef::npos)
441  TokenPtr += End;
442  else
443  TokenPtr = CommentEnd;
444  formTextToken(T, TokenPtr);
445  return;
446  }
447  }
448  }
449 }
450 
451 void Lexer::setupAndLexVerbatimBlock(Token &T,
452  const char *TextBegin,
453  char Marker, const CommandInfo *Info) {
454  assert(Info->IsVerbatimBlockCommand);
455 
456  VerbatimBlockEndCommandName.clear();
457  VerbatimBlockEndCommandName.append(Marker == '\\' ? "\\" : "@");
458  VerbatimBlockEndCommandName.append(Info->EndCommandName);
459 
460  formTokenWithChars(T, TextBegin, tok::verbatim_block_begin);
461  T.setVerbatimBlockID(Info->getID());
462 
463  // If there is a newline following the verbatim opening command, skip the
464  // newline so that we don't create an tok::verbatim_block_line with empty
465  // text content.
466  if (BufferPtr != CommentEnd &&
467  isVerticalWhitespace(*BufferPtr)) {
468  BufferPtr = skipNewline(BufferPtr, CommentEnd);
469  State = LS_VerbatimBlockBody;
470  return;
471  }
472 
473  State = LS_VerbatimBlockFirstLine;
474 }
475 
476 void Lexer::lexVerbatimBlockFirstLine(Token &T) {
477 again:
478  assert(BufferPtr < CommentEnd);
479 
480  // FIXME: It would be better to scan the text once, finding either the block
481  // end command or newline.
482  //
483  // Extract current line.
484  const char *Newline = findNewline(BufferPtr, CommentEnd);
485  StringRef Line(BufferPtr, Newline - BufferPtr);
486 
487  // Look for end command in current line.
488  size_t Pos = Line.find(VerbatimBlockEndCommandName);
489  const char *TextEnd;
490  const char *NextLine;
491  if (Pos == StringRef::npos) {
492  // Current line is completely verbatim.
493  TextEnd = Newline;
494  NextLine = skipNewline(Newline, CommentEnd);
495  } else if (Pos == 0) {
496  // Current line contains just an end command.
497  const char *End = BufferPtr + VerbatimBlockEndCommandName.size();
498  StringRef Name(BufferPtr + 1, End - (BufferPtr + 1));
499  formTokenWithChars(T, End, tok::verbatim_block_end);
500  T.setVerbatimBlockID(Traits.getCommandInfo(Name)->getID());
501  State = LS_Normal;
502  return;
503  } else {
504  // There is some text, followed by end command. Extract text first.
505  TextEnd = BufferPtr + Pos;
506  NextLine = TextEnd;
507  // If there is only whitespace before end command, skip whitespace.
508  if (isWhitespace(BufferPtr, TextEnd)) {
509  BufferPtr = TextEnd;
510  goto again;
511  }
512  }
513 
514  StringRef Text(BufferPtr, TextEnd - BufferPtr);
515  formTokenWithChars(T, NextLine, tok::verbatim_block_line);
516  T.setVerbatimBlockText(Text);
517 
518  State = LS_VerbatimBlockBody;
519 }
520 
521 void Lexer::lexVerbatimBlockBody(Token &T) {
522  assert(State == LS_VerbatimBlockBody);
523 
524  if (CommentState == LCS_InsideCComment)
525  skipLineStartingDecorations();
526 
527  if (BufferPtr == CommentEnd) {
528  formTokenWithChars(T, BufferPtr, tok::verbatim_block_line);
529  T.setVerbatimBlockText("");
530  return;
531  }
532 
533  lexVerbatimBlockFirstLine(T);
534 }
535 
536 void Lexer::setupAndLexVerbatimLine(Token &T, const char *TextBegin,
537  const CommandInfo *Info) {
538  assert(Info->IsVerbatimLineCommand);
539  formTokenWithChars(T, TextBegin, tok::verbatim_line_name);
540  T.setVerbatimLineID(Info->getID());
541 
542  State = LS_VerbatimLineText;
543 }
544 
545 void Lexer::lexVerbatimLineText(Token &T) {
546  assert(State == LS_VerbatimLineText);
547 
548  // Extract current line.
549  const char *Newline = findNewline(BufferPtr, CommentEnd);
550  StringRef Text(BufferPtr, Newline - BufferPtr);
551  formTokenWithChars(T, Newline, tok::verbatim_line_text);
552  T.setVerbatimLineText(Text);
553 
554  State = LS_Normal;
555 }
556 
557 void Lexer::lexHTMLCharacterReference(Token &T) {
558  const char *TokenPtr = BufferPtr;
559  assert(*TokenPtr == '&');
560  TokenPtr++;
561  if (TokenPtr == CommentEnd) {
562  formTextToken(T, TokenPtr);
563  return;
564  }
565  const char *NamePtr;
566  bool isNamed = false;
567  bool isDecimal = false;
568  char C = *TokenPtr;
570  NamePtr = TokenPtr;
571  TokenPtr = skipNamedCharacterReference(TokenPtr, CommentEnd);
572  isNamed = true;
573  } else if (C == '#') {
574  TokenPtr++;
575  if (TokenPtr == CommentEnd) {
576  formTextToken(T, TokenPtr);
577  return;
578  }
579  C = *TokenPtr;
581  NamePtr = TokenPtr;
582  TokenPtr = skipDecimalCharacterReference(TokenPtr, CommentEnd);
583  isDecimal = true;
584  } else if (C == 'x' || C == 'X') {
585  TokenPtr++;
586  NamePtr = TokenPtr;
587  TokenPtr = skipHexCharacterReference(TokenPtr, CommentEnd);
588  } else {
589  formTextToken(T, TokenPtr);
590  return;
591  }
592  } else {
593  formTextToken(T, TokenPtr);
594  return;
595  }
596  if (NamePtr == TokenPtr || TokenPtr == CommentEnd ||
597  *TokenPtr != ';') {
598  formTextToken(T, TokenPtr);
599  return;
600  }
601  StringRef Name(NamePtr, TokenPtr - NamePtr);
602  TokenPtr++; // Skip semicolon.
603  StringRef Resolved;
604  if (isNamed)
605  Resolved = resolveHTMLNamedCharacterReference(Name);
606  else if (isDecimal)
607  Resolved = resolveHTMLDecimalCharacterReference(Name);
608  else
609  Resolved = resolveHTMLHexCharacterReference(Name);
610 
611  if (Resolved.empty()) {
612  formTextToken(T, TokenPtr);
613  return;
614  }
615  formTokenWithChars(T, TokenPtr, tok::text);
616  T.setText(Resolved);
617 }
618 
619 void Lexer::setupAndLexHTMLStartTag(Token &T) {
620  assert(BufferPtr[0] == '<' &&
621  isHTMLIdentifierStartingCharacter(BufferPtr[1]));
622  const char *TagNameEnd = skipHTMLIdentifier(BufferPtr + 2, CommentEnd);
623  StringRef Name(BufferPtr + 1, TagNameEnd - (BufferPtr + 1));
624  if (!isHTMLTagName(Name)) {
625  formTextToken(T, TagNameEnd);
626  return;
627  }
628 
629  formTokenWithChars(T, TagNameEnd, tok::html_start_tag);
630  T.setHTMLTagStartName(Name);
631 
632  BufferPtr = skipWhitespace(BufferPtr, CommentEnd);
633 
634  const char C = *BufferPtr;
635  if (BufferPtr != CommentEnd &&
636  (C == '>' || C == '/' || isHTMLIdentifierStartingCharacter(C)))
637  State = LS_HTMLStartTag;
638 }
639 
640 void Lexer::lexHTMLStartTag(Token &T) {
641  assert(State == LS_HTMLStartTag);
642 
643  const char *TokenPtr = BufferPtr;
644  char C = *TokenPtr;
645  if (isHTMLIdentifierCharacter(C)) {
646  TokenPtr = skipHTMLIdentifier(TokenPtr, CommentEnd);
647  StringRef Ident(BufferPtr, TokenPtr - BufferPtr);
648  formTokenWithChars(T, TokenPtr, tok::html_ident);
649  T.setHTMLIdent(Ident);
650  } else {
651  switch (C) {
652  case '=':
653  TokenPtr++;
654  formTokenWithChars(T, TokenPtr, tok::html_equals);
655  break;
656  case '\"':
657  case '\'': {
658  const char *OpenQuote = TokenPtr;
659  TokenPtr = skipHTMLQuotedString(TokenPtr, CommentEnd);
660  const char *ClosingQuote = TokenPtr;
661  if (TokenPtr != CommentEnd) // Skip closing quote.
662  TokenPtr++;
663  formTokenWithChars(T, TokenPtr, tok::html_quoted_string);
664  T.setHTMLQuotedString(StringRef(OpenQuote + 1,
665  ClosingQuote - (OpenQuote + 1)));
666  break;
667  }
668  case '>':
669  TokenPtr++;
670  formTokenWithChars(T, TokenPtr, tok::html_greater);
671  State = LS_Normal;
672  return;
673  case '/':
674  TokenPtr++;
675  if (TokenPtr != CommentEnd && *TokenPtr == '>') {
676  TokenPtr++;
677  formTokenWithChars(T, TokenPtr, tok::html_slash_greater);
678  } else
679  formTextToken(T, TokenPtr);
680 
681  State = LS_Normal;
682  return;
683  }
684  }
685 
686  // Now look ahead and return to normal state if we don't see any HTML tokens
687  // ahead.
688  BufferPtr = skipWhitespace(BufferPtr, CommentEnd);
689  if (BufferPtr == CommentEnd) {
690  State = LS_Normal;
691  return;
692  }
693 
694  C = *BufferPtr;
695  if (!isHTMLIdentifierStartingCharacter(C) &&
696  C != '=' && C != '\"' && C != '\'' && C != '>') {
697  State = LS_Normal;
698  return;
699  }
700 }
701 
702 void Lexer::setupAndLexHTMLEndTag(Token &T) {
703  assert(BufferPtr[0] == '<' && BufferPtr[1] == '/');
704 
705  const char *TagNameBegin = skipWhitespace(BufferPtr + 2, CommentEnd);
706  const char *TagNameEnd = skipHTMLIdentifier(TagNameBegin, CommentEnd);
707  StringRef Name(TagNameBegin, TagNameEnd - TagNameBegin);
708  if (!isHTMLTagName(Name)) {
709  formTextToken(T, TagNameEnd);
710  return;
711  }
712 
713  const char *End = skipWhitespace(TagNameEnd, CommentEnd);
714 
715  formTokenWithChars(T, End, tok::html_end_tag);
716  T.setHTMLTagEndName(Name);
717 
718  if (BufferPtr != CommentEnd && *BufferPtr == '>')
719  State = LS_HTMLEndTag;
720 }
721 
722 void Lexer::lexHTMLEndTag(Token &T) {
723  assert(BufferPtr != CommentEnd && *BufferPtr == '>');
724 
725  formTokenWithChars(T, BufferPtr + 1, tok::html_greater);
726  State = LS_Normal;
727 }
728 
729 Lexer::Lexer(llvm::BumpPtrAllocator &Allocator, DiagnosticsEngine &Diags,
730  const CommandTraits &Traits,
731  SourceLocation FileLoc,
732  const char *BufferStart, const char *BufferEnd):
733  Allocator(Allocator), Diags(Diags), Traits(Traits),
734  BufferStart(BufferStart), BufferEnd(BufferEnd),
735  FileLoc(FileLoc), BufferPtr(BufferStart),
736  CommentState(LCS_BeforeComment), State(LS_Normal) {
737 }
738 
739 void Lexer::lex(Token &T) {
740 again:
741  switch (CommentState) {
742  case LCS_BeforeComment:
743  if (BufferPtr == BufferEnd) {
744  formTokenWithChars(T, BufferPtr, tok::eof);
745  return;
746  }
747 
748  assert(*BufferPtr == '/');
749  BufferPtr++; // Skip first slash.
750  switch(*BufferPtr) {
751  case '/': { // BCPL comment.
752  BufferPtr++; // Skip second slash.
753 
754  if (BufferPtr != BufferEnd) {
755  // Skip Doxygen magic marker, if it is present.
756  // It might be missing because of a typo //< or /*<, or because we
757  // merged this non-Doxygen comment into a bunch of Doxygen comments
758  // around it: /** ... */ /* ... */ /** ... */
759  const char C = *BufferPtr;
760  if (C == '/' || C == '!')
761  BufferPtr++;
762  }
763 
764  // Skip less-than symbol that marks trailing comments.
765  // Skip it even if the comment is not a Doxygen one, because //< and /*<
766  // are frequent typos.
767  if (BufferPtr != BufferEnd && *BufferPtr == '<')
768  BufferPtr++;
769 
770  CommentState = LCS_InsideBCPLComment;
771  if (State != LS_VerbatimBlockBody && State != LS_VerbatimBlockFirstLine)
772  State = LS_Normal;
773  CommentEnd = findBCPLCommentEnd(BufferPtr, BufferEnd);
774  goto again;
775  }
776  case '*': { // C comment.
777  BufferPtr++; // Skip star.
778 
779  // Skip Doxygen magic marker.
780  const char C = *BufferPtr;
781  if ((C == '*' && *(BufferPtr + 1) != '/') || C == '!')
782  BufferPtr++;
783 
784  // Skip less-than symbol that marks trailing comments.
785  if (BufferPtr != BufferEnd && *BufferPtr == '<')
786  BufferPtr++;
787 
788  CommentState = LCS_InsideCComment;
789  State = LS_Normal;
790  CommentEnd = findCCommentEnd(BufferPtr, BufferEnd);
791  goto again;
792  }
793  default:
794  llvm_unreachable("second character of comment should be '/' or '*'");
795  }
796 
797  case LCS_BetweenComments: {
798  // Consecutive comments are extracted only if there is only whitespace
799  // between them. So we can search for the start of the next comment.
800  const char *EndWhitespace = BufferPtr;
801  while(EndWhitespace != BufferEnd && *EndWhitespace != '/')
802  EndWhitespace++;
803 
804  // Turn any whitespace between comments (and there is only whitespace
805  // between them -- guaranteed by comment extraction) into a newline. We
806  // have two newlines between C comments in total (first one was synthesized
807  // after a comment).
808  formTokenWithChars(T, EndWhitespace, tok::newline);
809 
810  CommentState = LCS_BeforeComment;
811  break;
812  }
813 
814  case LCS_InsideBCPLComment:
815  case LCS_InsideCComment:
816  if (BufferPtr != CommentEnd) {
817  lexCommentText(T);
818  break;
819  } else {
820  // Skip C comment closing sequence.
821  if (CommentState == LCS_InsideCComment) {
822  assert(BufferPtr[0] == '*' && BufferPtr[1] == '/');
823  BufferPtr += 2;
824  assert(BufferPtr <= BufferEnd);
825 
826  // Synthenize newline just after the C comment, regardless if there is
827  // actually a newline.
828  formTokenWithChars(T, BufferPtr, tok::newline);
829 
830  CommentState = LCS_BetweenComments;
831  break;
832  } else {
833  // Don't synthesized a newline after BCPL comment.
834  CommentState = LCS_BetweenComments;
835  goto again;
836  }
837  }
838  }
839 }
840 
841 StringRef Lexer::getSpelling(const Token &Tok,
842  const SourceManager &SourceMgr,
843  bool *Invalid) const {
844  SourceLocation Loc = Tok.getLocation();
845  std::pair<FileID, unsigned> LocInfo = SourceMgr.getDecomposedLoc(Loc);
846 
847  bool InvalidTemp = false;
848  StringRef File = SourceMgr.getBufferData(LocInfo.first, &InvalidTemp);
849  if (InvalidTemp) {
850  *Invalid = true;
851  return StringRef();
852  }
853 
854  const char *Begin = File.data() + LocInfo.second;
855  return StringRef(Begin, Tok.getLength());
856 }
857 
858 } // end namespace comments
859 } // end namespace clang
void setHTMLQuotedString(StringRef Str)
Definition: CommentLexer.h:200
static DiagnosticBuilder Diag(DiagnosticsEngine *Diags, const LangOptions &Features, FullSourceLoc TokLoc, const char *TokBegin, const char *TokRangeBegin, const char *TokRangeEnd, unsigned DiagID)
Produce a diagnostic highlighting some portion of a literal.
void setHTMLTagStartName(StringRef Name)
Definition: CommentLexer.h:178
static LLVM_READONLY bool isDigit(unsigned char c)
Return true if this character is an ASCII digit: [0-9].
Definition: CharInfo.h:94
SourceLocation getLocWithOffset(int Offset) const
Return a source location with the specified offset from this SourceLocation.
static StringRef convertCodePointToUTF8(llvm::BumpPtrAllocator &Allocator, unsigned CodePoint)
SourceLocation getEndLocation() const LLVM_READONLY
Definition: CommentLexer.h:84
unsigned getLength() const LLVM_READONLY
Definition: CommentLexer.h:96
static LLVM_READONLY bool isWhitespace(unsigned char c)
Return true if this character is horizontal or vertical ASCII whitespace: &#39; &#39;, &#39;\t&#39;, &#39;\f&#39;, &#39;\v&#39;, &#39;\n&#39;, &#39;\r&#39;.
Definition: CharInfo.h:88
static LLVM_READONLY bool isLetter(unsigned char c)
Return true if this character is an ASCII letter: [a-zA-Z].
Definition: CharInfo.h:112
void setLength(unsigned L)
Definition: CommentLexer.h:97
void setText(StringRef Text)
Definition: CommentLexer.h:104
const char * EndCommandName
Name of the command that ends the verbatim block.
StringRef getBufferData(FileID FID, bool *Invalid=nullptr) const
Return a StringRef to the source buffer data for the specified FileID.
void setVerbatimLineText(StringRef Text)
Definition: CommentLexer.h:167
Information about a single command.
LineState State
void setCommandID(unsigned ID)
Definition: CommentLexer.h:126
static LLVM_READONLY bool isHorizontalWhitespace(unsigned char c)
Returns true if this character is horizontal ASCII whitespace: &#39; &#39;, &#39;\t&#39;, &#39;\f&#39;, &#39;\v&#39;.
Definition: CharInfo.h:71
void setVerbatimBlockID(unsigned ID)
Definition: CommentLexer.h:136
const FormatToken & Tok
Concrete class used by the front-end to report problems and issues.
Definition: Diagnostic.h:147
void setLocation(SourceLocation SL)
Definition: CommentLexer.h:82
void dump(const Lexer &L, const SourceManager &SM) const
unsigned IsVerbatimLineCommand
True if this command is a verbatim line command.
static unsigned skipWhitespace(unsigned Idx, StringRef Str, unsigned Length)
Skip over whitespace in the string, starting at the given index.
void dump(const SourceManager &SM) const
static bool isHTMLHexCharacterReferenceCharacter(char C)
SourceLocation End
void setUnknownCommandName(StringRef Name)
Definition: CommentLexer.h:115
const AnnotatedLine * Line
const FunctionProtoType * T
StringRef getSpelling(const Token &Tok, const SourceManager &SourceMgr, bool *Invalid=nullptr) const
SourceLocation Begin
void setVerbatimLineID(unsigned ID)
Definition: CommentLexer.h:157
void setHTMLTagEndName(StringRef Name)
Definition: CommentLexer.h:211
static bool isHTMLNamedCharacterReferenceCharacter(char C)
SourceLocation getLocation() const LLVM_READONLY
Definition: CommentLexer.h:81
const SourceManager & SM
Definition: Format.cpp:1308
static bool isNamed(const NamedDecl *ND, const char(&Str)[Len])
Definition: Decl.cpp:2606
void setVerbatimBlockText(StringRef Text)
Definition: CommentLexer.h:146
This class provides information about commands that can be used in comments.
Kind
Encodes a location in the source.
static LLVM_READONLY bool isAlphanumeric(unsigned char c)
Return true if this character is an ASCII letter or digit: [a-zA-Z0-9].
Definition: CharInfo.h:118
Comment lexer.
Definition: CommentLexer.h:221
Dataflow Directional Tag Classes.
unsigned IsVerbatimBlockCommand
True if this command is a verbatim-like block command.
void setKind(tok::TokenKind K)
Definition: CommentLexer.h:91
static bool isHTMLDecimalCharacterReferenceCharacter(char C)
Comment token.
Definition: CommentLexer.h:56
static LLVM_READONLY bool isVerticalWhitespace(unsigned char c)
Returns true if this character is vertical ASCII whitespace: &#39;\n&#39;, &#39;\r&#39;.
Definition: CharInfo.h:79
static FixItHint CreateReplacement(CharSourceRange RemoveRange, StringRef Code)
Create a code modification hint that replaces the given source range with the given code string...
Definition: Diagnostic.h:127
StringRef Text
Definition: Format.cpp:1317
void setHTMLIdent(StringRef Name)
Definition: CommentLexer.h:189
A trivial tuple used to represent a source range.
This class handles loading and caching of source files into memory.
std::pair< FileID, unsigned > getDecomposedLoc(SourceLocation Loc) const
Decompose the specified location into a raw FileID + Offset pair.
static LLVM_READONLY bool isHexDigit(unsigned char c)
Return true if this character is an ASCII hex digit: [0-9a-fA-F].
Definition: CharInfo.h:124