| //===--- Pragma.cpp - Pragma registration and handling --------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file was developed by Chris Lattner and is distributed under |
| // the University of Illinois Open Source License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements the PragmaHandler/PragmaTable interfaces and implements |
| // pragma related methods of the Preprocessor class. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "clang/Lex/Pragma.h" |
| #include "clang/Lex/PPCallbacks.h" |
| #include "clang/Lex/HeaderSearch.h" |
| #include "clang/Lex/Preprocessor.h" |
| #include "clang/Basic/Diagnostic.h" |
| #include "clang/Basic/FileManager.h" |
| #include "clang/Basic/SourceManager.h" |
| #include "llvm/ADT/SmallVector.h" |
| using namespace clang; |
| |
| // Out-of-line destructor to provide a home for the class. |
| PragmaHandler::~PragmaHandler() { |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // PragmaNamespace Implementation. |
| //===----------------------------------------------------------------------===// |
| |
| |
| PragmaNamespace::~PragmaNamespace() { |
| for (unsigned i = 0, e = Handlers.size(); i != e; ++i) |
| delete Handlers[i]; |
| } |
| |
| /// FindHandler - Check to see if there is already a handler for the |
| /// specified name. If not, return the handler for the null identifier if it |
| /// exists, otherwise return null. If IgnoreNull is true (the default) then |
| /// the null handler isn't returned on failure to match. |
| PragmaHandler *PragmaNamespace::FindHandler(const IdentifierInfo *Name, |
| bool IgnoreNull) const { |
| PragmaHandler *NullHandler = 0; |
| for (unsigned i = 0, e = Handlers.size(); i != e; ++i) { |
| if (Handlers[i]->getName() == Name) |
| return Handlers[i]; |
| |
| if (Handlers[i]->getName() == 0) |
| NullHandler = Handlers[i]; |
| } |
| return IgnoreNull ? 0 : NullHandler; |
| } |
| |
| void PragmaNamespace::HandlePragma(Preprocessor &PP, Token &Tok) { |
| // Read the 'namespace' that the directive is in, e.g. STDC. Do not macro |
| // expand it, the user can have a STDC #define, that should not affect this. |
| PP.LexUnexpandedToken(Tok); |
| |
| // Get the handler for this token. If there is no handler, ignore the pragma. |
| PragmaHandler *Handler = FindHandler(Tok.getIdentifierInfo(), false); |
| if (Handler == 0) return; |
| |
| // Otherwise, pass it down. |
| Handler->HandlePragma(PP, Tok); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Preprocessor Pragma Directive Handling. |
| //===----------------------------------------------------------------------===// |
| |
| /// HandlePragmaDirective - The "#pragma" directive has been parsed. Lex the |
| /// rest of the pragma, passing it to the registered pragma handlers. |
| void Preprocessor::HandlePragmaDirective() { |
| ++NumPragma; |
| |
| // Invoke the first level of pragma handlers which reads the namespace id. |
| Token Tok; |
| PragmaHandlers->HandlePragma(*this, Tok); |
| |
| // If the pragma handler didn't read the rest of the line, consume it now. |
| if (CurLexer->ParsingPreprocessorDirective) |
| DiscardUntilEndOfDirective(); |
| } |
| |
| /// Handle_Pragma - Read a _Pragma directive, slice it up, process it, then |
| /// return the first token after the directive. The _Pragma token has just |
| /// been read into 'Tok'. |
| void Preprocessor::Handle_Pragma(Token &Tok) { |
| // Remember the pragma token location. |
| SourceLocation PragmaLoc = Tok.getLocation(); |
| |
| // Read the '('. |
| Lex(Tok); |
| if (Tok.getKind() != tok::l_paren) |
| return Diag(PragmaLoc, diag::err__Pragma_malformed); |
| |
| // Read the '"..."'. |
| Lex(Tok); |
| if (Tok.getKind() != tok::string_literal && |
| Tok.getKind() != tok::wide_string_literal) |
| return Diag(PragmaLoc, diag::err__Pragma_malformed); |
| |
| // Remember the string. |
| std::string StrVal = getSpelling(Tok); |
| SourceLocation StrLoc = Tok.getLocation(); |
| |
| // Read the ')'. |
| Lex(Tok); |
| if (Tok.getKind() != tok::r_paren) |
| return Diag(PragmaLoc, diag::err__Pragma_malformed); |
| |
| // The _Pragma is lexically sound. Destringize according to C99 6.10.9.1. |
| if (StrVal[0] == 'L') // Remove L prefix. |
| StrVal.erase(StrVal.begin()); |
| assert(StrVal[0] == '"' && StrVal[StrVal.size()-1] == '"' && |
| "Invalid string token!"); |
| |
| // Remove the front quote, replacing it with a space, so that the pragma |
| // contents appear to have a space before them. |
| StrVal[0] = ' '; |
| |
| // Replace the terminating quote with a \n\0. |
| StrVal[StrVal.size()-1] = '\n'; |
| StrVal += '\0'; |
| |
| // Remove escaped quotes and escapes. |
| for (unsigned i = 0, e = StrVal.size(); i != e-1; ++i) { |
| if (StrVal[i] == '\\' && |
| (StrVal[i+1] == '\\' || StrVal[i+1] == '"')) { |
| // \\ -> '\' and \" -> '"'. |
| StrVal.erase(StrVal.begin()+i); |
| --e; |
| } |
| } |
| |
| // Plop the string (including the newline and trailing null) into a buffer |
| // where we can lex it. |
| SourceLocation TokLoc = CreateString(&StrVal[0], StrVal.size(), StrLoc); |
| const char *StrData = SourceMgr.getCharacterData(TokLoc); |
| |
| // Make and enter a lexer object so that we lex and expand the tokens just |
| // like any others. |
| Lexer *TL = new Lexer(TokLoc, *this, |
| StrData, StrData+StrVal.size()-1 /* no null */); |
| |
| // Ensure that the lexer thinks it is inside a directive, so that end \n will |
| // return an EOM token. |
| TL->ParsingPreprocessorDirective = true; |
| |
| // This lexer really is for _Pragma. |
| TL->Is_PragmaLexer = true; |
| |
| EnterSourceFileWithLexer(TL, 0); |
| |
| // With everything set up, lex this as a #pragma directive. |
| HandlePragmaDirective(); |
| |
| // Finally, return whatever came after the pragma directive. |
| return Lex(Tok); |
| } |
| |
| |
| |
| /// HandlePragmaOnce - Handle #pragma once. OnceTok is the 'once'. |
| /// |
| void Preprocessor::HandlePragmaOnce(Token &OnceTok) { |
| if (isInPrimaryFile()) { |
| Diag(OnceTok, diag::pp_pragma_once_in_main_file); |
| return; |
| } |
| |
| // Get the current file lexer we're looking at. Ignore _Pragma 'files' etc. |
| SourceLocation FileLoc = getCurrentFileLexer()->getFileLoc(); |
| |
| // Mark the file as a once-only file now. |
| HeaderInfo.MarkFileIncludeOnce(SourceMgr.getFileEntryForLoc(FileLoc)); |
| } |
| |
| /// HandlePragmaPoison - Handle #pragma GCC poison. PoisonTok is the 'poison'. |
| /// |
| void Preprocessor::HandlePragmaPoison(Token &PoisonTok) { |
| Token Tok; |
| |
| while (1) { |
| // Read the next token to poison. While doing this, pretend that we are |
| // skipping while reading the identifier to poison. |
| // This avoids errors on code like: |
| // #pragma GCC poison X |
| // #pragma GCC poison X |
| if (CurLexer) CurLexer->LexingRawMode = true; |
| LexUnexpandedToken(Tok); |
| if (CurLexer) CurLexer->LexingRawMode = false; |
| |
| // If we reached the end of line, we're done. |
| if (Tok.getKind() == tok::eom) return; |
| |
| // Can only poison identifiers. |
| if (Tok.getKind() != tok::identifier) { |
| Diag(Tok, diag::err_pp_invalid_poison); |
| return; |
| } |
| |
| // Look up the identifier info for the token. We disabled identifier lookup |
| // by saying we're skipping contents, so we need to do this manually. |
| IdentifierInfo *II = LookUpIdentifierInfo(Tok); |
| |
| // Already poisoned. |
| if (II->isPoisoned()) continue; |
| |
| // If this is a macro identifier, emit a warning. |
| if (II->hasMacroDefinition()) |
| Diag(Tok, diag::pp_poisoning_existing_macro); |
| |
| // Finally, poison it! |
| II->setIsPoisoned(); |
| } |
| } |
| |
| /// HandlePragmaSystemHeader - Implement #pragma GCC system_header. We know |
| /// that the whole directive has been parsed. |
| void Preprocessor::HandlePragmaSystemHeader(Token &SysHeaderTok) { |
| if (isInPrimaryFile()) { |
| Diag(SysHeaderTok, diag::pp_pragma_sysheader_in_main_file); |
| return; |
| } |
| |
| // Get the current file lexer we're looking at. Ignore _Pragma 'files' etc. |
| Lexer *TheLexer = getCurrentFileLexer(); |
| |
| // Mark the file as a system header. |
| const FileEntry *File = SourceMgr.getFileEntryForLoc(TheLexer->getFileLoc()); |
| HeaderInfo.MarkFileSystemHeader(File); |
| |
| // Notify the client, if desired, that we are in a new source file. |
| if (Callbacks) |
| Callbacks->FileChanged(TheLexer->getSourceLocation(TheLexer->BufferPtr), |
| PPCallbacks::SystemHeaderPragma, |
| DirectoryLookup::SystemHeaderDir); |
| } |
| |
| /// HandlePragmaDependency - Handle #pragma GCC dependency "foo" blah. |
| /// |
| void Preprocessor::HandlePragmaDependency(Token &DependencyTok) { |
| Token FilenameTok; |
| CurLexer->LexIncludeFilename(FilenameTok); |
| |
| // If the token kind is EOM, the error has already been diagnosed. |
| if (FilenameTok.getKind() == tok::eom) |
| return; |
| |
| // Reserve a buffer to get the spelling. |
| llvm::SmallVector<char, 128> FilenameBuffer; |
| FilenameBuffer.resize(FilenameTok.getLength()); |
| |
| const char *FilenameStart = &FilenameBuffer[0]; |
| unsigned Len = getSpelling(FilenameTok, FilenameStart); |
| const char *FilenameEnd = FilenameStart+Len; |
| bool isAngled = GetIncludeFilenameSpelling(FilenameTok.getLocation(), |
| FilenameStart, FilenameEnd); |
| // If GetIncludeFilenameSpelling set the start ptr to null, there was an |
| // error. |
| if (FilenameStart == 0) |
| return; |
| |
| // Search include directories for this file. |
| const DirectoryLookup *CurDir; |
| const FileEntry *File = LookupFile(FilenameStart, FilenameEnd, |
| isAngled, 0, CurDir); |
| if (File == 0) |
| return Diag(FilenameTok, diag::err_pp_file_not_found, |
| std::string(FilenameStart, FilenameEnd)); |
| |
| SourceLocation FileLoc = getCurrentFileLexer()->getFileLoc(); |
| const FileEntry *CurFile = SourceMgr.getFileEntryForLoc(FileLoc); |
| |
| // If this file is older than the file it depends on, emit a diagnostic. |
| if (CurFile && CurFile->getModificationTime() < File->getModificationTime()) { |
| // Lex tokens at the end of the message and include them in the message. |
| std::string Message; |
| Lex(DependencyTok); |
| while (DependencyTok.getKind() != tok::eom) { |
| Message += getSpelling(DependencyTok) + " "; |
| Lex(DependencyTok); |
| } |
| |
| Message.erase(Message.end()-1); |
| Diag(FilenameTok, diag::pp_out_of_date_dependency, Message); |
| } |
| } |
| |
| |
| /// AddPragmaHandler - Add the specified pragma handler to the preprocessor. |
| /// If 'Namespace' is non-null, then it is a token required to exist on the |
| /// pragma line before the pragma string starts, e.g. "STDC" or "GCC". |
| void Preprocessor::AddPragmaHandler(const char *Namespace, |
| PragmaHandler *Handler) { |
| PragmaNamespace *InsertNS = PragmaHandlers; |
| |
| // If this is specified to be in a namespace, step down into it. |
| if (Namespace) { |
| IdentifierInfo *NSID = getIdentifierInfo(Namespace); |
| |
| // If there is already a pragma handler with the name of this namespace, |
| // we either have an error (directive with the same name as a namespace) or |
| // we already have the namespace to insert into. |
| if (PragmaHandler *Existing = PragmaHandlers->FindHandler(NSID)) { |
| InsertNS = Existing->getIfNamespace(); |
| assert(InsertNS != 0 && "Cannot have a pragma namespace and pragma" |
| " handler with the same name!"); |
| } else { |
| // Otherwise, this namespace doesn't exist yet, create and insert the |
| // handler for it. |
| InsertNS = new PragmaNamespace(NSID); |
| PragmaHandlers->AddPragma(InsertNS); |
| } |
| } |
| |
| // Check to make sure we don't already have a pragma for this identifier. |
| assert(!InsertNS->FindHandler(Handler->getName()) && |
| "Pragma handler already exists for this identifier!"); |
| InsertNS->AddPragma(Handler); |
| } |
| |
| namespace { |
| struct PragmaOnceHandler : public PragmaHandler { |
| PragmaOnceHandler(const IdentifierInfo *OnceID) : PragmaHandler(OnceID) {} |
| virtual void HandlePragma(Preprocessor &PP, Token &OnceTok) { |
| PP.CheckEndOfDirective("#pragma once"); |
| PP.HandlePragmaOnce(OnceTok); |
| } |
| }; |
| |
| struct PragmaPoisonHandler : public PragmaHandler { |
| PragmaPoisonHandler(const IdentifierInfo *ID) : PragmaHandler(ID) {} |
| virtual void HandlePragma(Preprocessor &PP, Token &PoisonTok) { |
| PP.HandlePragmaPoison(PoisonTok); |
| } |
| }; |
| |
| struct PragmaSystemHeaderHandler : public PragmaHandler { |
| PragmaSystemHeaderHandler(const IdentifierInfo *ID) : PragmaHandler(ID) {} |
| virtual void HandlePragma(Preprocessor &PP, Token &SHToken) { |
| PP.HandlePragmaSystemHeader(SHToken); |
| PP.CheckEndOfDirective("#pragma"); |
| } |
| }; |
| struct PragmaDependencyHandler : public PragmaHandler { |
| PragmaDependencyHandler(const IdentifierInfo *ID) : PragmaHandler(ID) {} |
| virtual void HandlePragma(Preprocessor &PP, Token &DepToken) { |
| PP.HandlePragmaDependency(DepToken); |
| } |
| }; |
| } // end anonymous namespace |
| |
| |
| /// RegisterBuiltinPragmas - Install the standard preprocessor pragmas: |
| /// #pragma GCC poison/system_header/dependency and #pragma once. |
| void Preprocessor::RegisterBuiltinPragmas() { |
| AddPragmaHandler(0, new PragmaOnceHandler(getIdentifierInfo("once"))); |
| AddPragmaHandler("GCC", new PragmaPoisonHandler(getIdentifierInfo("poison"))); |
| AddPragmaHandler("GCC", new PragmaSystemHeaderHandler( |
| getIdentifierInfo("system_header"))); |
| AddPragmaHandler("GCC", new PragmaDependencyHandler( |
| getIdentifierInfo("dependency"))); |
| } |