Preprocessor.h revision 7bfaaaecb3113f955db31e8d8a51acffd1bc0c27
1//===--- Preprocessor.h - C Language Family Preprocessor --------*- 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// This file defines the Preprocessor interface. 11// 12//===----------------------------------------------------------------------===// 13 14#ifndef LLVM_CLANG_LEX_PREPROCESSOR_H 15#define LLVM_CLANG_LEX_PREPROCESSOR_H 16 17#include "clang/Lex/Lexer.h" 18#include "clang/Lex/PPCallbacks.h" 19#include "clang/Lex/TokenLexer.h" 20#include "clang/Basic/IdentifierTable.h" 21#include "clang/Basic/SourceLocation.h" 22#include "llvm/ADT/DenseMap.h" 23 24namespace clang { 25 26class SourceManager; 27class FileManager; 28class FileEntry; 29class HeaderSearch; 30class PragmaNamespace; 31class PragmaHandler; 32class ScratchBuffer; 33class TargetInfo; 34class PPCallbacks; 35class DirectoryLookup; 36 37/// Preprocessor - This object engages in a tight little dance with the lexer to 38/// efficiently preprocess tokens. Lexers know only about tokens within a 39/// single source file, and don't know anything about preprocessor-level issues 40/// like the #include stack, token expansion, etc. 41/// 42class Preprocessor { 43 Diagnostic &Diags; 44 const LangOptions &Features; 45 TargetInfo &Target; 46 FileManager &FileMgr; 47 SourceManager &SourceMgr; 48 ScratchBuffer *ScratchBuf; 49 HeaderSearch &HeaderInfo; 50 51 /// Identifiers for builtin macros and other builtins. 52 IdentifierInfo *Ident__LINE__, *Ident__FILE__; // __LINE__, __FILE__ 53 IdentifierInfo *Ident__DATE__, *Ident__TIME__; // __DATE__, __TIME__ 54 IdentifierInfo *Ident__INCLUDE_LEVEL__; // __INCLUDE_LEVEL__ 55 IdentifierInfo *Ident__BASE_FILE__; // __BASE_FILE__ 56 IdentifierInfo *Ident__TIMESTAMP__; // __TIMESTAMP__ 57 IdentifierInfo *Ident_Pragma, *Ident__VA_ARGS__; // _Pragma, __VA_ARGS__ 58 59 SourceLocation DATELoc, TIMELoc; 60 61 enum { 62 /// MaxIncludeStackDepth - Maximum depth of #includes. 63 MaxAllowedIncludeStackDepth = 200 64 }; 65 66 // State that is set before the preprocessor begins. 67 bool KeepComments : 1; 68 bool KeepMacroComments : 1; 69 70 // State that changes while the preprocessor runs: 71 bool DisableMacroExpansion : 1; // True if macro expansion is disabled. 72 bool InMacroArgs : 1; // True if parsing fn macro invocation args. 73 74 /// CacheTokens - True when the lexed tokens are cached for backtracking. 75 bool CacheTokens : 1; 76 77 /// Identifiers - This is mapping/lookup information for all identifiers in 78 /// the program, including program keywords. 79 IdentifierTable Identifiers; 80 81 /// Selectors - This table contains all the selectors in the program. Unlike 82 /// IdentifierTable above, this table *isn't* populated by the preprocessor. 83 /// It is declared/instantiated here because it's role/lifetime is 84 /// conceptually similar the IdentifierTable. In addition, the current control 85 /// flow (in clang::ParseAST()), make it convenient to put here. 86 /// FIXME: Make sure the lifetime of Identifiers/Selectors *isn't* tied to 87 /// the lifetime fo the preprocessor. 88 SelectorTable Selectors; 89 90 /// PragmaHandlers - This tracks all of the pragmas that the client registered 91 /// with this preprocessor. 92 PragmaNamespace *PragmaHandlers; 93 94 /// CurLexer - This is the current top of the stack that we're lexing from if 95 /// not expanding a macro. One of CurLexer and CurTokenLexer must be null. 96 Lexer *CurLexer; 97 98 /// CurLookup - The DirectoryLookup structure used to find the current 99 /// FileEntry, if CurLexer is non-null and if applicable. This allows us to 100 /// implement #include_next and find directory-specific properties. 101 const DirectoryLookup *CurDirLookup; 102 103 /// CurTokenLexer - This is the current macro we are expanding, if we are 104 /// expanding a macro. One of CurLexer and CurTokenLexer must be null. 105 TokenLexer *CurTokenLexer; 106 107 /// IncludeMacroStack - This keeps track of the stack of files currently 108 /// #included, and macros currently being expanded from, not counting 109 /// CurLexer/CurTokenLexer. 110 struct IncludeStackInfo { 111 Lexer *TheLexer; 112 const DirectoryLookup *TheDirLookup; 113 TokenLexer *TheTokenLexer; 114 IncludeStackInfo(Lexer *L, const DirectoryLookup *D, TokenLexer *TL) 115 : TheLexer(L), TheDirLookup(D), TheTokenLexer(TL) { 116 } 117 }; 118 std::vector<IncludeStackInfo> IncludeMacroStack; 119 120 /// Callbacks - These are actions invoked when some preprocessor activity is 121 /// encountered (e.g. a file is #included, etc). 122 PPCallbacks *Callbacks; 123 124 /// Macros - For each IdentifierInfo with 'HasMacro' set, we keep a mapping 125 /// to the actual definition of the macro. 126 llvm::DenseMap<IdentifierInfo*, MacroInfo*> Macros; 127 128 // Various statistics we track for performance analysis. 129 unsigned NumDirectives, NumIncluded, NumDefined, NumUndefined, NumPragma; 130 unsigned NumIf, NumElse, NumEndif; 131 unsigned NumEnteredSourceFiles, MaxIncludeStackDepth; 132 unsigned NumMacroExpanded, NumFnMacroExpanded, NumBuiltinMacroExpanded; 133 unsigned NumFastMacroExpanded, NumTokenPaste, NumFastTokenPaste; 134 unsigned NumSkipped; 135 136 /// Predefines - This string is the predefined macros that preprocessor 137 /// should use from the command line etc. 138 std::string Predefines; 139 140 /// TokenLexerCache - Cache macro expanders to reduce malloc traffic. 141 enum { TokenLexerCacheSize = 8 }; 142 unsigned NumCachedTokenLexers; 143 TokenLexer *TokenLexerCache[TokenLexerCacheSize]; 144 145 // Cached tokens state. 146 147 typedef std::vector<Token> CachedTokensTy; 148 149 /// CachedTokens - Cached tokens are stored here when we do backtracking or 150 /// lookahead. They are "lexed" by the CachingLex() method. 151 CachedTokensTy CachedTokens; 152 153 /// CachedLexPos - The position of the cached token that CachingLex() should 154 /// "lex" next. If it points beyond the CachedTokens vector, it means that 155 /// a normal Lex() should be invoked. 156 CachedTokensTy::size_type CachedLexPos; 157 158 /// CachedBacktrackPos - Gets set by the EnableBacktrackAtThisPos() method, 159 /// to indicate the position where CachedLexPos should be set when the 160 /// BackTrack() method is invoked. 161 CachedTokensTy::size_type CachedBacktrackPos; 162 163public: 164 Preprocessor(Diagnostic &diags, const LangOptions &opts, TargetInfo &target, 165 SourceManager &SM, HeaderSearch &Headers); 166 ~Preprocessor(); 167 168 Diagnostic &getDiagnostics() const { return Diags; } 169 const LangOptions &getLangOptions() const { return Features; } 170 TargetInfo &getTargetInfo() const { return Target; } 171 FileManager &getFileManager() const { return FileMgr; } 172 SourceManager &getSourceManager() const { return SourceMgr; } 173 HeaderSearch &getHeaderSearchInfo() const { return HeaderInfo; } 174 175 IdentifierTable &getIdentifierTable() { return Identifiers; } 176 SelectorTable &getSelectorTable() { return Selectors; } 177 178 inline FullSourceLoc getFullLoc(SourceLocation Loc) const { 179 return FullSourceLoc(Loc, getSourceManager()); 180 } 181 182 /// SetCommentRetentionState - Control whether or not the preprocessor retains 183 /// comments in output. 184 void SetCommentRetentionState(bool KeepComments, bool KeepMacroComments) { 185 this->KeepComments = KeepComments | KeepMacroComments; 186 this->KeepMacroComments = KeepMacroComments; 187 } 188 189 bool getCommentRetentionState() const { return KeepComments; } 190 191 /// isCurrentLexer - Return true if we are lexing directly from the specified 192 /// lexer. 193 bool isCurrentLexer(const Lexer *L) const { 194 return CurLexer == L; 195 } 196 197 /// getCurrentLexer - Return the current file lexer being lexed from. Note 198 /// that this ignores any potentially active macro expansions and _Pragma 199 /// expansions going on at the time. 200 Lexer *getCurrentFileLexer() const; 201 202 /// getPPCallbacks/setPPCallbacks - Accessors for preprocessor callbacks. 203 /// Note that this class takes ownership of any PPCallbacks object given to 204 /// it. 205 PPCallbacks *getPPCallbacks() const { return Callbacks; } 206 void setPPCallbacks(PPCallbacks *C) { 207 delete Callbacks; 208 Callbacks = C; 209 } 210 211 /// getMacroInfo - Given an identifier, return the MacroInfo it is #defined to 212 /// or null if it isn't #define'd. 213 MacroInfo *getMacroInfo(IdentifierInfo *II) const { 214 return II->hasMacroDefinition() ? Macros.find(II)->second : 0; 215 } 216 217 /// setMacroInfo - Specify a macro for this identifier. 218 /// 219 void setMacroInfo(IdentifierInfo *II, MacroInfo *MI); 220 221 const std::string &getPredefines() const { return Predefines; } 222 /// setPredefines - Set the predefines for this Preprocessor. These 223 /// predefines are automatically injected when parsing the main file. 224 void setPredefines(const char *P) { Predefines = P; } 225 void setPredefines(const std::string &P) { Predefines = P; } 226 227 /// getIdentifierInfo - Return information about the specified preprocessor 228 /// identifier token. The version of this method that takes two character 229 /// pointers is preferred unless the identifier is already available as a 230 /// string (this avoids allocation and copying of memory to construct an 231 /// std::string). 232 IdentifierInfo *getIdentifierInfo(const char *NameStart, 233 const char *NameEnd) { 234 return &Identifiers.get(NameStart, NameEnd); 235 } 236 IdentifierInfo *getIdentifierInfo(const char *NameStr) { 237 return getIdentifierInfo(NameStr, NameStr+strlen(NameStr)); 238 } 239 240 /// AddPragmaHandler - Add the specified pragma handler to the preprocessor. 241 /// If 'Namespace' is non-null, then it is a token required to exist on the 242 /// pragma line before the pragma string starts, e.g. "STDC" or "GCC". 243 void AddPragmaHandler(const char *Namespace, PragmaHandler *Handler); 244 245 /// EnterMainSourceFile - Enter the specified FileID as the main source file, 246 /// which implicitly adds the builtin defines etc. 247 void EnterMainSourceFile(); 248 249 /// EnterSourceFile - Add a source file to the top of the include stack and 250 /// start lexing tokens from it instead of the current buffer. If isMainFile 251 /// is true, this is the main file for the translation unit. 252 void EnterSourceFile(unsigned CurFileID, const DirectoryLookup *Dir); 253 254 /// EnterMacro - Add a Macro to the top of the include stack and start lexing 255 /// tokens from it instead of the current buffer. Args specifies the 256 /// tokens input to a function-like macro. 257 void EnterMacro(Token &Identifier, MacroArgs *Args); 258 259 /// EnterTokenStream - Add a "macro" context to the top of the include stack, 260 /// which will cause the lexer to start returning the specified tokens. 261 /// 262 /// If DisableMacroExpansion is true, tokens lexed from the token stream will 263 /// not be subject to further macro expansion. Otherwise, these tokens will 264 /// be re-macro-expanded when/if expansion is enabled. 265 /// 266 /// If OwnsTokens is false, this method assumes that the specified stream of 267 /// tokens has a permanent owner somewhere, so they do not need to be copied. 268 /// If it is true, it assumes the array of tokens is allocated with new[] and 269 /// must be freed. 270 /// 271 void EnterTokenStream(const Token *Toks, unsigned NumToks, 272 bool DisableMacroExpansion, bool OwnsTokens); 273 274 /// RemoveTopOfLexerStack - Pop the current lexer/macro exp off the top of the 275 /// lexer stack. This should only be used in situations where the current 276 /// state of the top-of-stack lexer is known. 277 void RemoveTopOfLexerStack(); 278 279 /// EnableBacktrackAtThisPos - From the point that this method is called, and 280 /// until DisableBacktrack() or Backtrack() is called, the Preprocessor keeps 281 /// track of the lexed tokens so that a subsequent Backtrack() call will make 282 /// the Preprocessor re-lex the same tokens. 283 /// 284 /// EnableBacktrackAtThisPos should not be called again until DisableBacktrack 285 /// or Backtrack is called. 286 /// 287 /// NOTE: *DO NOT* forget to call either DisableBacktrack() or Backtrack() at 288 /// some point after EnableBacktrackAtThisPos. If you don't, caching of tokens 289 /// will continue indefinitely. 290 /// 291 void EnableBacktrackAtThisPos() { 292 assert(!CacheTokens && "Backtrack is already enabled!"); 293 CacheTokens = true; 294 CachedBacktrackPos = CachedLexPos; 295 EnterCachingLexMode(); 296 } 297 298 /// DisableBacktrack - Stop the caching of tokens that was enabled by 299 /// EnableBacktrackAtThisPos(). 300 void DisableBacktrack() { 301 assert(CacheTokens && "Backtrack is not enabled!"); 302 CacheTokens = false; 303 } 304 305 /// Backtrack - Make Preprocessor re-lex the tokens that were lexed since 306 /// EnableBacktrackAtThisPos() was previously called. 307 void Backtrack() { 308 assert(CacheTokens && "Backtrack is not enabled!"); 309 CacheTokens = false; 310 CachedLexPos = CachedBacktrackPos; 311 } 312 313 /// isBacktrackEnabled - True if EnableBacktrackAtThisPos() was called and 314 /// caching of tokens is on. 315 bool isBacktrackEnabled() const { return CacheTokens; } 316 317 /// Lex - To lex a token from the preprocessor, just pull a token from the 318 /// current lexer or macro object. 319 void Lex(Token &Result) { 320 if (CurLexer) 321 CurLexer->Lex(Result); 322 else if (CurTokenLexer) 323 CurTokenLexer->Lex(Result); 324 else 325 CachingLex(Result); 326 } 327 328 /// LexNonComment - Lex a token. If it's a comment, keep lexing until we get 329 /// something not a comment. This is useful in -E -C mode where comments 330 /// would foul up preprocessor directive handling. 331 void LexNonComment(Token &Result) { 332 do 333 Lex(Result); 334 while (Result.getKind() == tok::comment); 335 } 336 337 /// LexUnexpandedToken - This is just like Lex, but this disables macro 338 /// expansion of identifier tokens. 339 void LexUnexpandedToken(Token &Result) { 340 // Disable macro expansion. 341 bool OldVal = DisableMacroExpansion; 342 DisableMacroExpansion = true; 343 // Lex the token. 344 Lex(Result); 345 346 // Reenable it. 347 DisableMacroExpansion = OldVal; 348 } 349 350 /// LookAhead - This peeks ahead N tokens and returns that token without 351 /// consuming any tokens. LookAhead(0) returns the next token that would be 352 /// returned by Lex(), LookAhead(1) returns the token after it, etc. This 353 /// returns normal tokens after phase 5. As such, it is equivalent to using 354 /// 'Lex', not 'LexUnexpandedToken'. 355 const Token &LookAhead(unsigned N) { 356 if (CachedLexPos + N < CachedTokens.size()) 357 return CachedTokens[CachedLexPos+N]; 358 else 359 return PeekAhead(N+1); 360 } 361 362 /// Diag - Forwarding function for diagnostics. This emits a diagnostic at 363 /// the specified Token's location, translating the token's start 364 /// position in the current buffer into a SourcePosition object for rendering. 365 void Diag(SourceLocation Loc, unsigned DiagID); 366 void Diag(SourceLocation Loc, unsigned DiagID, const std::string &Msg); 367 void Diag(SourceLocation Loc, unsigned DiagID, const std::string &Msg, 368 const SourceRange &R1, const SourceRange &R2); 369 void Diag(SourceLocation Loc, unsigned DiagID, const SourceRange &R); 370 void Diag(SourceLocation Loc, unsigned DiagID, const SourceRange &R1, 371 const SourceRange &R2); 372 void Diag(const Token &Tok, unsigned DiagID) { 373 Diag(Tok.getLocation(), DiagID); 374 } 375 void Diag(const Token &Tok, unsigned DiagID, const std::string &Msg) { 376 Diag(Tok.getLocation(), DiagID, Msg); 377 } 378 379 /// getSpelling() - Return the 'spelling' of the Tok token. The spelling of a 380 /// token is the characters used to represent the token in the source file 381 /// after trigraph expansion and escaped-newline folding. In particular, this 382 /// wants to get the true, uncanonicalized, spelling of things like digraphs 383 /// UCNs, etc. 384 std::string getSpelling(const Token &Tok) const; 385 386 /// getSpelling - This method is used to get the spelling of a token into a 387 /// preallocated buffer, instead of as an std::string. The caller is required 388 /// to allocate enough space for the token, which is guaranteed to be at least 389 /// Tok.getLength() bytes long. The length of the actual result is returned. 390 /// 391 /// Note that this method may do two possible things: it may either fill in 392 /// the buffer specified with characters, or it may *change the input pointer* 393 /// to point to a constant buffer with the data already in it (avoiding a 394 /// copy). The caller is not allowed to modify the returned buffer pointer 395 /// if an internal buffer is returned. 396 unsigned getSpelling(const Token &Tok, const char *&Buffer) const; 397 398 399 /// CreateString - Plop the specified string into a scratch buffer and return 400 /// a location for it. If specified, the source location provides a source 401 /// location for the token. 402 SourceLocation CreateString(const char *Buf, unsigned Len, 403 SourceLocation SourceLoc = SourceLocation()); 404 405 /// DumpToken - Print the token to stderr, used for debugging. 406 /// 407 void DumpToken(const Token &Tok, bool DumpFlags = false) const; 408 void DumpLocation(SourceLocation Loc) const; 409 void DumpMacro(const MacroInfo &MI) const; 410 411 /// AdvanceToTokenCharacter - Given a location that specifies the start of a 412 /// token, return a new location that specifies a character within the token. 413 SourceLocation AdvanceToTokenCharacter(SourceLocation TokStart,unsigned Char); 414 415 /// IncrementPasteCounter - Increment the counters for the number of token 416 /// paste operations performed. If fast was specified, this is a 'fast paste' 417 /// case we handled. 418 /// 419 void IncrementPasteCounter(bool isFast) { 420 if (isFast) 421 ++NumFastTokenPaste; 422 else 423 ++NumTokenPaste; 424 } 425 426 void PrintStats(); 427 428 /// HandleMicrosoftCommentPaste - When the macro expander pastes together a 429 /// comment (/##/) in microsoft mode, this method handles updating the current 430 /// state, returning the token on the next source line. 431 void HandleMicrosoftCommentPaste(Token &Tok); 432 433 //===--------------------------------------------------------------------===// 434 // Preprocessor callback methods. These are invoked by a lexer as various 435 // directives and events are found. 436 437 /// LookUpIdentifierInfo - Given a tok::identifier token, look up the 438 /// identifier information for the token and install it into the token. 439 IdentifierInfo *LookUpIdentifierInfo(Token &Identifier, 440 const char *BufPtr = 0); 441 442 /// HandleIdentifier - This callback is invoked when the lexer reads an 443 /// identifier and has filled in the tokens IdentifierInfo member. This 444 /// callback potentially macro expands it or turns it into a named token (like 445 /// 'for'). 446 void HandleIdentifier(Token &Identifier); 447 448 449 /// HandleEndOfFile - This callback is invoked when the lexer hits the end of 450 /// the current file. This either returns the EOF token and returns true, or 451 /// pops a level off the include stack and returns false, at which point the 452 /// client should call lex again. 453 bool HandleEndOfFile(Token &Result, bool isEndOfMacro = false); 454 455 /// HandleEndOfTokenLexer - This callback is invoked when the current 456 /// TokenLexer hits the end of its token stream. 457 bool HandleEndOfTokenLexer(Token &Result); 458 459 /// HandleDirective - This callback is invoked when the lexer sees a # token 460 /// at the start of a line. This consumes the directive, modifies the 461 /// lexer/preprocessor state, and advances the lexer(s) so that the next token 462 /// read is the correct one. 463 void HandleDirective(Token &Result); 464 465 /// CheckEndOfDirective - Ensure that the next token is a tok::eom token. If 466 /// not, emit a diagnostic and consume up until the eom. 467 void CheckEndOfDirective(const char *Directive); 468private: 469 /// isInPrimaryFile - Return true if we're in the top-level file, not in a 470 /// #include. 471 bool isInPrimaryFile() const; 472 473 /// isSystemHeader - Return true if F is a system header. 474 bool isSystemHeader(const FileEntry* F) const; 475 476 /// DiscardUntilEndOfDirective - Read and discard all tokens remaining on the 477 /// current line until the tok::eom token is found. 478 void DiscardUntilEndOfDirective(); 479 480 /// ReadMacroName - Lex and validate a macro name, which occurs after a 481 /// #define or #undef. This emits a diagnostic, sets the token kind to eom, 482 /// and discards the rest of the macro line if the macro name is invalid. 483 void ReadMacroName(Token &MacroNameTok, char isDefineUndef = 0); 484 485 /// ReadMacroDefinitionArgList - The ( starting an argument list of a macro 486 /// definition has just been read. Lex the rest of the arguments and the 487 /// closing ), updating MI with what we learn. Return true if an error occurs 488 /// parsing the arg list. 489 bool ReadMacroDefinitionArgList(MacroInfo *MI); 490 491 /// SkipExcludedConditionalBlock - We just read a #if or related directive and 492 /// decided that the subsequent tokens are in the #if'd out portion of the 493 /// file. Lex the rest of the file, until we see an #endif. If 494 /// FoundNonSkipPortion is true, then we have already emitted code for part of 495 /// this #if directive, so #else/#elif blocks should never be entered. If 496 /// FoundElse is false, then #else directives are ok, if not, then we have 497 /// already seen one so a #else directive is a duplicate. When this returns, 498 /// the caller can lex the first valid token. 499 void SkipExcludedConditionalBlock(SourceLocation IfTokenLoc, 500 bool FoundNonSkipPortion, bool FoundElse); 501 502 /// EvaluateDirectiveExpression - Evaluate an integer constant expression that 503 /// may occur after a #if or #elif directive and return it as a bool. If the 504 /// expression is equivalent to "!defined(X)" return X in IfNDefMacro. 505 bool EvaluateDirectiveExpression(IdentifierInfo *&IfNDefMacro); 506 507 /// RegisterBuiltinPragmas - Install the standard preprocessor pragmas: 508 /// #pragma GCC poison/system_header/dependency and #pragma once. 509 void RegisterBuiltinPragmas(); 510 511 /// RegisterBuiltinMacros - Register builtin macros, such as __LINE__ with the 512 /// identifier table. 513 void RegisterBuiltinMacros(); 514 IdentifierInfo *RegisterBuiltinMacro(const char *Name); 515 516 /// HandleMacroExpandedIdentifier - If an identifier token is read that is to 517 /// be expanded as a macro, handle it and return the next token as 'Tok'. If 518 /// the macro should not be expanded return true, otherwise return false. 519 bool HandleMacroExpandedIdentifier(Token &Tok, MacroInfo *MI); 520 521 /// isNextPPTokenLParen - Determine whether the next preprocessor token to be 522 /// lexed is a '('. If so, consume the token and return true, if not, this 523 /// method should have no observable side-effect on the lexed tokens. 524 bool isNextPPTokenLParen(); 525 526 /// ReadFunctionLikeMacroArgs - After reading "MACRO(", this method is 527 /// invoked to read all of the formal arguments specified for the macro 528 /// invocation. This returns null on error. 529 MacroArgs *ReadFunctionLikeMacroArgs(Token &MacroName, MacroInfo *MI); 530 531 /// ExpandBuiltinMacro - If an identifier token is read that is to be expanded 532 /// as a builtin macro, handle it and return the next token as 'Tok'. 533 void ExpandBuiltinMacro(Token &Tok); 534 535 /// Handle_Pragma - Read a _Pragma directive, slice it up, process it, then 536 /// return the first token after the directive. The _Pragma token has just 537 /// been read into 'Tok'. 538 void Handle_Pragma(Token &Tok); 539 540 541 /// EnterSourceFileWithLexer - Add a lexer to the top of the include stack and 542 /// start lexing tokens from it instead of the current buffer. 543 void EnterSourceFileWithLexer(Lexer *TheLexer, const DirectoryLookup *Dir); 544 545 /// GetIncludeFilenameSpelling - Turn the specified lexer token into a fully 546 /// checked and spelled filename, e.g. as an operand of #include. This returns 547 /// true if the input filename was in <>'s or false if it were in ""'s. The 548 /// caller is expected to provide a buffer that is large enough to hold the 549 /// spelling of the filename, but is also expected to handle the case when 550 /// this method decides to use a different buffer. 551 bool GetIncludeFilenameSpelling(SourceLocation Loc, 552 const char *&BufStart, const char *&BufEnd); 553 554 /// LookupFile - Given a "foo" or <foo> reference, look up the indicated file, 555 /// return null on failure. isAngled indicates whether the file reference is 556 /// for system #include's or not (i.e. using <> instead of ""). 557 const FileEntry *LookupFile(const char *FilenameStart,const char *FilenameEnd, 558 bool isAngled, const DirectoryLookup *FromDir, 559 const DirectoryLookup *&CurDir); 560 561 //===--------------------------------------------------------------------===// 562 // Caching stuff. 563 void CachingLex(Token &Result); 564 bool InCachingLexMode() const { return CurLexer == 0 && CurTokenLexer == 0; } 565 void EnterCachingLexMode(); 566 void ExitCachingLexMode() { 567 if (InCachingLexMode()) 568 RemoveTopOfLexerStack(); 569 } 570 const Token &PeekAhead(unsigned N); 571 572 //===--------------------------------------------------------------------===// 573 /// Handle*Directive - implement the various preprocessor directives. These 574 /// should side-effect the current preprocessor object so that the next call 575 /// to Lex() will return the appropriate token next. 576 577 void HandleUserDiagnosticDirective(Token &Tok, bool isWarning); 578 void HandleIdentSCCSDirective(Token &Tok); 579 580 // File inclusion. 581 void HandleIncludeDirective(Token &Tok, 582 const DirectoryLookup *LookupFrom = 0, 583 bool isImport = false); 584 void HandleIncludeNextDirective(Token &Tok); 585 void HandleImportDirective(Token &Tok); 586 587 // Macro handling. 588 void HandleDefineDirective(Token &Tok); 589 void HandleUndefDirective(Token &Tok); 590 // HandleAssertDirective(Token &Tok); 591 // HandleUnassertDirective(Token &Tok); 592 593 // Conditional Inclusion. 594 void HandleIfdefDirective(Token &Tok, bool isIfndef, 595 bool ReadAnyTokensBeforeDirective); 596 void HandleIfDirective(Token &Tok, bool ReadAnyTokensBeforeDirective); 597 void HandleEndifDirective(Token &Tok); 598 void HandleElseDirective(Token &Tok); 599 void HandleElifDirective(Token &Tok); 600 601 // Pragmas. 602 void HandlePragmaDirective(); 603public: 604 void HandlePragmaOnce(Token &OnceTok); 605 void HandlePragmaMark(); 606 void HandlePragmaPoison(Token &PoisonTok); 607 void HandlePragmaSystemHeader(Token &SysHeaderTok); 608 void HandlePragmaDependency(Token &DependencyTok); 609}; 610 611/// PreprocessorFactory - A generic factory interface for lazily creating 612/// Preprocessor objects on-demand when they are needed. 613class PreprocessorFactory { 614public: 615 virtual ~PreprocessorFactory(); 616 virtual Preprocessor* CreatePreprocessor() = 0; 617}; 618 619} // end namespace clang 620 621#endif 622