clang  3.9.0
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  SourceRange CommandRange(Loc.getLocWithOffset(1),
382  getSourceLocation(TokenPtr));
383  Diag(Loc, diag::warn_correct_comment_command_name)
384  << CommandName << CorrectedName
385  << FixItHint::CreateReplacement(CommandRange, CorrectedName);
386  } else {
387  formTokenWithChars(T, TokenPtr, tok::unknown_command);
388  T.setUnknownCommandName(CommandName);
389  Diag(T.getLocation(), diag::warn_unknown_comment_command_name);
390  return;
391  }
392  }
393  if (Info->IsVerbatimBlockCommand) {
394  setupAndLexVerbatimBlock(T, TokenPtr, *BufferPtr, Info);
395  return;
396  }
397  if (Info->IsVerbatimLineCommand) {
398  setupAndLexVerbatimLine(T, TokenPtr, Info);
399  return;
400  }
401  formTokenWithChars(T, TokenPtr, CommandKind);
402  T.setCommandID(Info->getID());
403  return;
404  }
405 
406  case '&':
407  lexHTMLCharacterReference(T);
408  return;
409 
410  case '<': {
411  TokenPtr++;
412  if (TokenPtr == CommentEnd) {
413  formTextToken(T, TokenPtr);
414  return;
415  }
416  const char C = *TokenPtr;
417  if (isHTMLIdentifierStartingCharacter(C))
418  setupAndLexHTMLStartTag(T);
419  else if (C == '/')
420  setupAndLexHTMLEndTag(T);
421  else
422  formTextToken(T, TokenPtr);
423  return;
424  }
425 
426  case '\n':
427  case '\r':
428  TokenPtr = skipNewline(TokenPtr, CommentEnd);
429  formTokenWithChars(T, TokenPtr, tok::newline);
430 
431  if (CommentState == LCS_InsideCComment)
432  skipLineStartingDecorations();
433  return;
434 
435  default: {
436  size_t End = StringRef(TokenPtr, CommentEnd - TokenPtr).
437  find_first_of("\n\r\\@&<");
438  if (End != StringRef::npos)
439  TokenPtr += End;
440  else
441  TokenPtr = CommentEnd;
442  formTextToken(T, TokenPtr);
443  return;
444  }
445  }
446  }
447 }
448 
449 void Lexer::setupAndLexVerbatimBlock(Token &T,
450  const char *TextBegin,
451  char Marker, const CommandInfo *Info) {
452  assert(Info->IsVerbatimBlockCommand);
453 
454  VerbatimBlockEndCommandName.clear();
455  VerbatimBlockEndCommandName.append(Marker == '\\' ? "\\" : "@");
456  VerbatimBlockEndCommandName.append(Info->EndCommandName);
457 
458  formTokenWithChars(T, TextBegin, tok::verbatim_block_begin);
459  T.setVerbatimBlockID(Info->getID());
460 
461  // If there is a newline following the verbatim opening command, skip the
462  // newline so that we don't create an tok::verbatim_block_line with empty
463  // text content.
464  if (BufferPtr != CommentEnd &&
465  isVerticalWhitespace(*BufferPtr)) {
466  BufferPtr = skipNewline(BufferPtr, CommentEnd);
467  State = LS_VerbatimBlockBody;
468  return;
469  }
470 
471  State = LS_VerbatimBlockFirstLine;
472 }
473 
474 void Lexer::lexVerbatimBlockFirstLine(Token &T) {
475 again:
476  assert(BufferPtr < CommentEnd);
477 
478  // FIXME: It would be better to scan the text once, finding either the block
479  // end command or newline.
480  //
481  // Extract current line.
482  const char *Newline = findNewline(BufferPtr, CommentEnd);
483  StringRef Line(BufferPtr, Newline - BufferPtr);
484 
485  // Look for end command in current line.
486  size_t Pos = Line.find(VerbatimBlockEndCommandName);
487  const char *TextEnd;
488  const char *NextLine;
489  if (Pos == StringRef::npos) {
490  // Current line is completely verbatim.
491  TextEnd = Newline;
492  NextLine = skipNewline(Newline, CommentEnd);
493  } else if (Pos == 0) {
494  // Current line contains just an end command.
495  const char *End = BufferPtr + VerbatimBlockEndCommandName.size();
496  StringRef Name(BufferPtr + 1, End - (BufferPtr + 1));
497  formTokenWithChars(T, End, tok::verbatim_block_end);
498  T.setVerbatimBlockID(Traits.getCommandInfo(Name)->getID());
499  State = LS_Normal;
500  return;
501  } else {
502  // There is some text, followed by end command. Extract text first.
503  TextEnd = BufferPtr + Pos;
504  NextLine = TextEnd;
505  // If there is only whitespace before end command, skip whitespace.
506  if (isWhitespace(BufferPtr, TextEnd)) {
507  BufferPtr = TextEnd;
508  goto again;
509  }
510  }
511 
512  StringRef Text(BufferPtr, TextEnd - BufferPtr);
513  formTokenWithChars(T, NextLine, tok::verbatim_block_line);
514  T.setVerbatimBlockText(Text);
515 
516  State = LS_VerbatimBlockBody;
517 }
518 
519 void Lexer::lexVerbatimBlockBody(Token &T) {
520  assert(State == LS_VerbatimBlockBody);
521 
522  if (CommentState == LCS_InsideCComment)
523  skipLineStartingDecorations();
524 
525  if (BufferPtr == CommentEnd) {
526  formTokenWithChars(T, BufferPtr, tok::verbatim_block_line);
527  T.setVerbatimBlockText("");
528  return;
529  }
530 
531  lexVerbatimBlockFirstLine(T);
532 }
533 
534 void Lexer::setupAndLexVerbatimLine(Token &T, const char *TextBegin,
535  const CommandInfo *Info) {
536  assert(Info->IsVerbatimLineCommand);
537  formTokenWithChars(T, TextBegin, tok::verbatim_line_name);
538  T.setVerbatimLineID(Info->getID());
539 
540  State = LS_VerbatimLineText;
541 }
542 
543 void Lexer::lexVerbatimLineText(Token &T) {
544  assert(State == LS_VerbatimLineText);
545 
546  // Extract current line.
547  const char *Newline = findNewline(BufferPtr, CommentEnd);
548  StringRef Text(BufferPtr, Newline - BufferPtr);
549  formTokenWithChars(T, Newline, tok::verbatim_line_text);
550  T.setVerbatimLineText(Text);
551 
552  State = LS_Normal;
553 }
554 
555 void Lexer::lexHTMLCharacterReference(Token &T) {
556  const char *TokenPtr = BufferPtr;
557  assert(*TokenPtr == '&');
558  TokenPtr++;
559  if (TokenPtr == CommentEnd) {
560  formTextToken(T, TokenPtr);
561  return;
562  }
563  const char *NamePtr;
564  bool isNamed = false;
565  bool isDecimal = false;
566  char C = *TokenPtr;
568  NamePtr = TokenPtr;
569  TokenPtr = skipNamedCharacterReference(TokenPtr, CommentEnd);
570  isNamed = true;
571  } else if (C == '#') {
572  TokenPtr++;
573  if (TokenPtr == CommentEnd) {
574  formTextToken(T, TokenPtr);
575  return;
576  }
577  C = *TokenPtr;
579  NamePtr = TokenPtr;
580  TokenPtr = skipDecimalCharacterReference(TokenPtr, CommentEnd);
581  isDecimal = true;
582  } else if (C == 'x' || C == 'X') {
583  TokenPtr++;
584  NamePtr = TokenPtr;
585  TokenPtr = skipHexCharacterReference(TokenPtr, CommentEnd);
586  } else {
587  formTextToken(T, TokenPtr);
588  return;
589  }
590  } else {
591  formTextToken(T, TokenPtr);
592  return;
593  }
594  if (NamePtr == TokenPtr || TokenPtr == CommentEnd ||
595  *TokenPtr != ';') {
596  formTextToken(T, TokenPtr);
597  return;
598  }
599  StringRef Name(NamePtr, TokenPtr - NamePtr);
600  TokenPtr++; // Skip semicolon.
601  StringRef Resolved;
602  if (isNamed)
603  Resolved = resolveHTMLNamedCharacterReference(Name);
604  else if (isDecimal)
605  Resolved = resolveHTMLDecimalCharacterReference(Name);
606  else
607  Resolved = resolveHTMLHexCharacterReference(Name);
608 
609  if (Resolved.empty()) {
610  formTextToken(T, TokenPtr);
611  return;
612  }
613  formTokenWithChars(T, TokenPtr, tok::text);
614  T.setText(Resolved);
615 }
616 
617 void Lexer::setupAndLexHTMLStartTag(Token &T) {
618  assert(BufferPtr[0] == '<' &&
619  isHTMLIdentifierStartingCharacter(BufferPtr[1]));
620  const char *TagNameEnd = skipHTMLIdentifier(BufferPtr + 2, CommentEnd);
621  StringRef Name(BufferPtr + 1, TagNameEnd - (BufferPtr + 1));
622  if (!isHTMLTagName(Name)) {
623  formTextToken(T, TagNameEnd);
624  return;
625  }
626 
627  formTokenWithChars(T, TagNameEnd, tok::html_start_tag);
628  T.setHTMLTagStartName(Name);
629 
630  BufferPtr = skipWhitespace(BufferPtr, CommentEnd);
631 
632  const char C = *BufferPtr;
633  if (BufferPtr != CommentEnd &&
634  (C == '>' || C == '/' || isHTMLIdentifierStartingCharacter(C)))
635  State = LS_HTMLStartTag;
636 }
637 
638 void Lexer::lexHTMLStartTag(Token &T) {
639  assert(State == LS_HTMLStartTag);
640 
641  const char *TokenPtr = BufferPtr;
642  char C = *TokenPtr;
643  if (isHTMLIdentifierCharacter(C)) {
644  TokenPtr = skipHTMLIdentifier(TokenPtr, CommentEnd);
645  StringRef Ident(BufferPtr, TokenPtr - BufferPtr);
646  formTokenWithChars(T, TokenPtr, tok::html_ident);
647  T.setHTMLIdent(Ident);
648  } else {
649  switch (C) {
650  case '=':
651  TokenPtr++;
652  formTokenWithChars(T, TokenPtr, tok::html_equals);
653  break;
654  case '\"':
655  case '\'': {
656  const char *OpenQuote = TokenPtr;
657  TokenPtr = skipHTMLQuotedString(TokenPtr, CommentEnd);
658  const char *ClosingQuote = TokenPtr;
659  if (TokenPtr != CommentEnd) // Skip closing quote.
660  TokenPtr++;
661  formTokenWithChars(T, TokenPtr, tok::html_quoted_string);
662  T.setHTMLQuotedString(StringRef(OpenQuote + 1,
663  ClosingQuote - (OpenQuote + 1)));
664  break;
665  }
666  case '>':
667  TokenPtr++;
668  formTokenWithChars(T, TokenPtr, tok::html_greater);
669  State = LS_Normal;
670  return;
671  case '/':
672  TokenPtr++;
673  if (TokenPtr != CommentEnd && *TokenPtr == '>') {
674  TokenPtr++;
675  formTokenWithChars(T, TokenPtr, tok::html_slash_greater);
676  } else
677  formTextToken(T, TokenPtr);
678 
679  State = LS_Normal;
680  return;
681  }
682  }
683 
684  // Now look ahead and return to normal state if we don't see any HTML tokens
685  // ahead.
686  BufferPtr = skipWhitespace(BufferPtr, CommentEnd);
687  if (BufferPtr == CommentEnd) {
688  State = LS_Normal;
689  return;
690  }
691 
692  C = *BufferPtr;
693  if (!isHTMLIdentifierStartingCharacter(C) &&
694  C != '=' && C != '\"' && C != '\'' && C != '>') {
695  State = LS_Normal;
696  return;
697  }
698 }
699 
700 void Lexer::setupAndLexHTMLEndTag(Token &T) {
701  assert(BufferPtr[0] == '<' && BufferPtr[1] == '/');
702 
703  const char *TagNameBegin = skipWhitespace(BufferPtr + 2, CommentEnd);
704  const char *TagNameEnd = skipHTMLIdentifier(TagNameBegin, CommentEnd);
705  StringRef Name(TagNameBegin, TagNameEnd - TagNameBegin);
706  if (!isHTMLTagName(Name)) {
707  formTextToken(T, TagNameEnd);
708  return;
709  }
710 
711  const char *End = skipWhitespace(TagNameEnd, CommentEnd);
712 
713  formTokenWithChars(T, End, tok::html_end_tag);
714  T.setHTMLTagEndName(Name);
715 
716  if (BufferPtr != CommentEnd && *BufferPtr == '>')
717  State = LS_HTMLEndTag;
718 }
719 
720 void Lexer::lexHTMLEndTag(Token &T) {
721  assert(BufferPtr != CommentEnd && *BufferPtr == '>');
722 
723  formTokenWithChars(T, BufferPtr + 1, tok::html_greater);
724  State = LS_Normal;
725 }
726 
727 Lexer::Lexer(llvm::BumpPtrAllocator &Allocator, DiagnosticsEngine &Diags,
728  const CommandTraits &Traits,
729  SourceLocation FileLoc,
730  const char *BufferStart, const char *BufferEnd):
731  Allocator(Allocator), Diags(Diags), Traits(Traits),
732  BufferStart(BufferStart), BufferEnd(BufferEnd),
733  FileLoc(FileLoc), BufferPtr(BufferStart),
734  CommentState(LCS_BeforeComment), State(LS_Normal) {
735 }
736 
737 void Lexer::lex(Token &T) {
738 again:
739  switch (CommentState) {
740  case LCS_BeforeComment:
741  if (BufferPtr == BufferEnd) {
742  formTokenWithChars(T, BufferPtr, tok::eof);
743  return;
744  }
745 
746  assert(*BufferPtr == '/');
747  BufferPtr++; // Skip first slash.
748  switch(*BufferPtr) {
749  case '/': { // BCPL comment.
750  BufferPtr++; // Skip second slash.
751 
752  if (BufferPtr != BufferEnd) {
753  // Skip Doxygen magic marker, if it is present.
754  // It might be missing because of a typo //< or /*<, or because we
755  // merged this non-Doxygen comment into a bunch of Doxygen comments
756  // around it: /** ... */ /* ... */ /** ... */
757  const char C = *BufferPtr;
758  if (C == '/' || C == '!')
759  BufferPtr++;
760  }
761 
762  // Skip less-than symbol that marks trailing comments.
763  // Skip it even if the comment is not a Doxygen one, because //< and /*<
764  // are frequent typos.
765  if (BufferPtr != BufferEnd && *BufferPtr == '<')
766  BufferPtr++;
767 
768  CommentState = LCS_InsideBCPLComment;
769  if (State != LS_VerbatimBlockBody && State != LS_VerbatimBlockFirstLine)
770  State = LS_Normal;
771  CommentEnd = findBCPLCommentEnd(BufferPtr, BufferEnd);
772  goto again;
773  }
774  case '*': { // C comment.
775  BufferPtr++; // Skip star.
776 
777  // Skip Doxygen magic marker.
778  const char C = *BufferPtr;
779  if ((C == '*' && *(BufferPtr + 1) != '/') || C == '!')
780  BufferPtr++;
781 
782  // Skip less-than symbol that marks trailing comments.
783  if (BufferPtr != BufferEnd && *BufferPtr == '<')
784  BufferPtr++;
785 
786  CommentState = LCS_InsideCComment;
787  State = LS_Normal;
788  CommentEnd = findCCommentEnd(BufferPtr, BufferEnd);
789  goto again;
790  }
791  default:
792  llvm_unreachable("second character of comment should be '/' or '*'");
793  }
794 
795  case LCS_BetweenComments: {
796  // Consecutive comments are extracted only if there is only whitespace
797  // between them. So we can search for the start of the next comment.
798  const char *EndWhitespace = BufferPtr;
799  while(EndWhitespace != BufferEnd && *EndWhitespace != '/')
800  EndWhitespace++;
801 
802  // Turn any whitespace between comments (and there is only whitespace
803  // between them -- guaranteed by comment extraction) into a newline. We
804  // have two newlines between C comments in total (first one was synthesized
805  // after a comment).
806  formTokenWithChars(T, EndWhitespace, tok::newline);
807 
808  CommentState = LCS_BeforeComment;
809  break;
810  }
811 
812  case LCS_InsideBCPLComment:
813  case LCS_InsideCComment:
814  if (BufferPtr != CommentEnd) {
815  lexCommentText(T);
816  break;
817  } else {
818  // Skip C comment closing sequence.
819  if (CommentState == LCS_InsideCComment) {
820  assert(BufferPtr[0] == '*' && BufferPtr[1] == '/');
821  BufferPtr += 2;
822  assert(BufferPtr <= BufferEnd);
823 
824  // Synthenize newline just after the C comment, regardless if there is
825  // actually a newline.
826  formTokenWithChars(T, BufferPtr, tok::newline);
827 
828  CommentState = LCS_BetweenComments;
829  break;
830  } else {
831  // Don't synthesized a newline after BCPL comment.
832  CommentState = LCS_BetweenComments;
833  goto again;
834  }
835  }
836  }
837 }
838 
839 StringRef Lexer::getSpelling(const Token &Tok,
840  const SourceManager &SourceMgr,
841  bool *Invalid) const {
842  SourceLocation Loc = Tok.getLocation();
843  std::pair<FileID, unsigned> LocInfo = SourceMgr.getDecomposedLoc(Loc);
844 
845  bool InvalidTemp = false;
846  StringRef File = SourceMgr.getBufferData(LocInfo.first, &InvalidTemp);
847  if (InvalidTemp) {
848  *Invalid = true;
849  return StringRef();
850  }
851 
852  const char *Begin = File.data() + LocInfo.second;
853  return StringRef(Begin, Tok.getLength());
854 }
855 
856 } // end namespace comments
857 } // end namespace clang
static LLVM_READONLY bool isDigit(unsigned char c)
Return true if this character is an ASCII digit: [0-9].
Definition: CharInfo.h:94
static StringRef convertCodePointToUTF8(llvm::BumpPtrAllocator &Allocator, unsigned CodePoint)
unsigned Length
unsigned getLength() const LLVM_READONLY
Definition: CommentLexer.h:97
static LLVM_READONLY bool isWhitespace(unsigned char c)
Return true if this character is horizontal or vertical ASCII whitespace: ' ', '\t', '\f', '\v', '\n', '\r'.
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
const CommandInfo * getCommandInfo(StringRef Name) const
class LLVM_ALIGNAS(8) DependentTemplateSpecializationType const IdentifierInfo * Name
Represents a template specialization type whose template cannot be resolved, e.g. ...
Definition: Type.h:4549
StringRef getBufferData(FileID FID, bool *Invalid=nullptr) const
Return a StringRef to the source buffer data for the specified FileID.
LineState State
static LLVM_READONLY bool isHorizontalWhitespace(unsigned char c)
Returns true if this character is horizontal ASCII whitespace: ' ', '\t', '\f', '\v'.
Definition: CharInfo.h:71
void dump(const Lexer &L, const SourceManager &SM) const
Concrete class used by the front-end to report problems and issues.
Definition: Diagnostic.h:135
void dump(const SourceManager &SM) const
static unsigned skipWhitespace(unsigned Idx, StringRef Str, unsigned Length)
Skip over whitespace in the string, starting at the given index.
const SmallVectorImpl< AnnotatedLine * >::const_iterator End
llvm::SpecificBumpPtrAllocator< StateNode > Allocator
static bool isHTMLHexCharacterReferenceCharacter(char C)
const CommandInfo * getCommandInfoOrNULL(StringRef Name) const
FormatToken * Token
const CommandInfo * getTypoCorrectCommandInfo(StringRef Typo) const
static bool isHTMLNamedCharacterReferenceCharacter(char C)
SourceLocation getLocation() const LLVM_READONLY
Definition: CommentLexer.h:82
const SourceManager & SM
Definition: Format.cpp:1184
static bool isNamed(const NamedDecl *ND, const char(&Str)[Len])
Definition: Decl.cpp:2515
This class provides information about commands that can be used in comments.
Kind
Encodes a location in the source.
AnnotatedLine & Line
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:222
static bool isHTMLDecimalCharacterReferenceCharacter(char C)
Comment token.
Definition: CommentLexer.h:57
StringRef getSpelling(const Token &Tok, const SourceManager &SourceMgr, bool *Invalid=nullptr) const
static LLVM_READONLY bool isVerticalWhitespace(unsigned char c)
Returns true if this character is vertical ASCII whitespace: '\n', '\r'.
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:115
StringRef Text
Definition: Format.cpp:1195
std::pair< FileID, unsigned > getDecomposedLoc(SourceLocation Loc) const
Decompose the specified location into a raw FileID + Offset pair.
This class handles loading and caching of source files into memory.
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