| //===--- PPLexerChange.cpp - Handle changing lexers in the preprocessor ---===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements pieces of the Preprocessor interface that manage the |
| // current lexer stack. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "clang/Lex/Preprocessor.h" |
| #include "clang/Basic/FileManager.h" |
| #include "clang/Basic/SourceManager.h" |
| #include "clang/Lex/HeaderSearch.h" |
| #include "clang/Lex/LexDiagnostic.h" |
| #include "clang/Lex/MacroInfo.h" |
| #include "llvm/ADT/StringSwitch.h" |
| #include "llvm/Support/FileSystem.h" |
| #include "llvm/Support/MemoryBuffer.h" |
| #include "llvm/Support/Path.h" |
| using namespace clang; |
| |
| PPCallbacks::~PPCallbacks() {} |
| |
| //===----------------------------------------------------------------------===// |
| // Miscellaneous Methods. |
| //===----------------------------------------------------------------------===// |
| |
| /// isInPrimaryFile - Return true if we're in the top-level file, not in a |
| /// \#include. This looks through macro expansions and active _Pragma lexers. |
| bool Preprocessor::isInPrimaryFile() const { |
| if (IsFileLexer()) |
| return IncludeMacroStack.empty(); |
| |
| // If there are any stacked lexers, we're in a #include. |
| assert(IsFileLexer(IncludeMacroStack[0]) && |
| "Top level include stack isn't our primary lexer?"); |
| for (unsigned i = 1, e = IncludeMacroStack.size(); i != e; ++i) |
| if (IsFileLexer(IncludeMacroStack[i])) |
| return false; |
| return true; |
| } |
| |
| /// getCurrentLexer - Return the current file lexer being lexed from. Note |
| /// that this ignores any potentially active macro expansions and _Pragma |
| /// expansions going on at the time. |
| PreprocessorLexer *Preprocessor::getCurrentFileLexer() const { |
| if (IsFileLexer()) |
| return CurPPLexer; |
| |
| // Look for a stacked lexer. |
| for (unsigned i = IncludeMacroStack.size(); i != 0; --i) { |
| const IncludeStackInfo& ISI = IncludeMacroStack[i-1]; |
| if (IsFileLexer(ISI)) |
| return ISI.ThePPLexer; |
| } |
| return 0; |
| } |
| |
| |
| //===----------------------------------------------------------------------===// |
| // Methods for Entering and Callbacks for leaving various contexts |
| //===----------------------------------------------------------------------===// |
| |
| /// EnterSourceFile - Add a source file to the top of the include stack and |
| /// start lexing tokens from it instead of the current buffer. |
| void Preprocessor::EnterSourceFile(FileID FID, const DirectoryLookup *CurDir, |
| SourceLocation Loc) { |
| assert(!CurTokenLexer && "Cannot #include a file inside a macro!"); |
| ++NumEnteredSourceFiles; |
| |
| if (MaxIncludeStackDepth < IncludeMacroStack.size()) |
| MaxIncludeStackDepth = IncludeMacroStack.size(); |
| |
| if (PTH) { |
| if (PTHLexer *PL = PTH->CreateLexer(FID)) { |
| EnterSourceFileWithPTH(PL, CurDir); |
| return; |
| } |
| } |
| |
| // Get the MemoryBuffer for this FID, if it fails, we fail. |
| bool Invalid = false; |
| const llvm::MemoryBuffer *InputFile = |
| getSourceManager().getBuffer(FID, Loc, &Invalid); |
| if (Invalid) { |
| SourceLocation FileStart = SourceMgr.getLocForStartOfFile(FID); |
| Diag(Loc, diag::err_pp_error_opening_file) |
| << std::string(SourceMgr.getBufferName(FileStart)) << ""; |
| return; |
| } |
| |
| if (isCodeCompletionEnabled() && |
| SourceMgr.getFileEntryForID(FID) == CodeCompletionFile) { |
| CodeCompletionFileLoc = SourceMgr.getLocForStartOfFile(FID); |
| CodeCompletionLoc = |
| CodeCompletionFileLoc.getLocWithOffset(CodeCompletionOffset); |
| } |
| |
| EnterSourceFileWithLexer(new Lexer(FID, InputFile, *this), CurDir); |
| return; |
| } |
| |
| /// EnterSourceFileWithLexer - Add a source file to the top of the include stack |
| /// and start lexing tokens from it instead of the current buffer. |
| void Preprocessor::EnterSourceFileWithLexer(Lexer *TheLexer, |
| const DirectoryLookup *CurDir) { |
| |
| // Add the current lexer to the include stack. |
| if (CurPPLexer || CurTokenLexer) |
| PushIncludeMacroStack(); |
| |
| CurLexer.reset(TheLexer); |
| CurPPLexer = TheLexer; |
| CurDirLookup = CurDir; |
| if (CurLexerKind != CLK_LexAfterModuleImport) |
| CurLexerKind = CLK_Lexer; |
| |
| // Notify the client, if desired, that we are in a new source file. |
| if (Callbacks && !CurLexer->Is_PragmaLexer) { |
| SrcMgr::CharacteristicKind FileType = |
| SourceMgr.getFileCharacteristic(CurLexer->getFileLoc()); |
| |
| Callbacks->FileChanged(CurLexer->getFileLoc(), |
| PPCallbacks::EnterFile, FileType); |
| } |
| } |
| |
| /// EnterSourceFileWithPTH - Add a source file to the top of the include stack |
| /// and start getting tokens from it using the PTH cache. |
| void Preprocessor::EnterSourceFileWithPTH(PTHLexer *PL, |
| const DirectoryLookup *CurDir) { |
| |
| if (CurPPLexer || CurTokenLexer) |
| PushIncludeMacroStack(); |
| |
| CurDirLookup = CurDir; |
| CurPTHLexer.reset(PL); |
| CurPPLexer = CurPTHLexer.get(); |
| if (CurLexerKind != CLK_LexAfterModuleImport) |
| CurLexerKind = CLK_PTHLexer; |
| |
| // Notify the client, if desired, that we are in a new source file. |
| if (Callbacks) { |
| FileID FID = CurPPLexer->getFileID(); |
| SourceLocation EnterLoc = SourceMgr.getLocForStartOfFile(FID); |
| SrcMgr::CharacteristicKind FileType = |
| SourceMgr.getFileCharacteristic(EnterLoc); |
| Callbacks->FileChanged(EnterLoc, PPCallbacks::EnterFile, FileType); |
| } |
| } |
| |
| /// EnterMacro - Add a Macro to the top of the include stack and start lexing |
| /// tokens from it instead of the current buffer. |
| void Preprocessor::EnterMacro(Token &Tok, SourceLocation ILEnd, |
| MacroInfo *Macro, MacroArgs *Args) { |
| TokenLexer *TokLexer; |
| if (NumCachedTokenLexers == 0) { |
| TokLexer = new TokenLexer(Tok, ILEnd, Macro, Args, *this); |
| } else { |
| TokLexer = TokenLexerCache[--NumCachedTokenLexers]; |
| TokLexer->Init(Tok, ILEnd, Macro, Args); |
| } |
| |
| PushIncludeMacroStack(); |
| CurDirLookup = 0; |
| CurTokenLexer.reset(TokLexer); |
| if (CurLexerKind != CLK_LexAfterModuleImport) |
| CurLexerKind = CLK_TokenLexer; |
| } |
| |
| /// EnterTokenStream - Add a "macro" context to the top of the include stack, |
| /// which will cause the lexer to start returning the specified tokens. |
| /// |
| /// If DisableMacroExpansion is true, tokens lexed from the token stream will |
| /// not be subject to further macro expansion. Otherwise, these tokens will |
| /// be re-macro-expanded when/if expansion is enabled. |
| /// |
| /// If OwnsTokens is false, this method assumes that the specified stream of |
| /// tokens has a permanent owner somewhere, so they do not need to be copied. |
| /// If it is true, it assumes the array of tokens is allocated with new[] and |
| /// must be freed. |
| /// |
| void Preprocessor::EnterTokenStream(const Token *Toks, unsigned NumToks, |
| bool DisableMacroExpansion, |
| bool OwnsTokens) { |
| // Create a macro expander to expand from the specified token stream. |
| TokenLexer *TokLexer; |
| if (NumCachedTokenLexers == 0) { |
| TokLexer = new TokenLexer(Toks, NumToks, DisableMacroExpansion, |
| OwnsTokens, *this); |
| } else { |
| TokLexer = TokenLexerCache[--NumCachedTokenLexers]; |
| TokLexer->Init(Toks, NumToks, DisableMacroExpansion, OwnsTokens); |
| } |
| |
| // Save our current state. |
| PushIncludeMacroStack(); |
| CurDirLookup = 0; |
| CurTokenLexer.reset(TokLexer); |
| if (CurLexerKind != CLK_LexAfterModuleImport) |
| CurLexerKind = CLK_TokenLexer; |
| } |
| |
| /// \brief Compute the relative path that names the given file relative to |
| /// the given directory. |
| static void computeRelativePath(FileManager &FM, const DirectoryEntry *Dir, |
| const FileEntry *File, |
| SmallString<128> &Result) { |
| Result.clear(); |
| |
| StringRef FilePath = File->getDir()->getName(); |
| StringRef Path = FilePath; |
| while (!Path.empty()) { |
| if (const DirectoryEntry *CurDir = FM.getDirectory(Path)) { |
| if (CurDir == Dir) { |
| Result = FilePath.substr(Path.size()); |
| llvm::sys::path::append(Result, |
| llvm::sys::path::filename(File->getName())); |
| return; |
| } |
| } |
| |
| Path = llvm::sys::path::parent_path(Path); |
| } |
| |
| Result = File->getName(); |
| } |
| |
| /// HandleEndOfFile - This callback is invoked when the lexer hits the end of |
| /// the current file. This either returns the EOF token or pops a level off |
| /// the include stack and keeps going. |
| bool Preprocessor::HandleEndOfFile(Token &Result, bool isEndOfMacro) { |
| assert(!CurTokenLexer && |
| "Ending a file when currently in a macro!"); |
| |
| // See if this file had a controlling macro. |
| if (CurPPLexer) { // Not ending a macro, ignore it. |
| if (const IdentifierInfo *ControllingMacro = |
| CurPPLexer->MIOpt.GetControllingMacroAtEndOfFile()) { |
| // Okay, this has a controlling macro, remember in HeaderFileInfo. |
| if (const FileEntry *FE = |
| SourceMgr.getFileEntryForID(CurPPLexer->getFileID())) { |
| HeaderInfo.SetFileControllingMacro(FE, ControllingMacro); |
| if (const IdentifierInfo *DefinedMacro = |
| CurPPLexer->MIOpt.GetDefinedMacro()) { |
| if (!ControllingMacro->hasMacroDefinition() && |
| DefinedMacro != ControllingMacro && |
| HeaderInfo.FirstTimeLexingFile(FE)) { |
| // Emit a warning for a bad header guard. |
| Diag(CurPPLexer->MIOpt.GetMacroLocation(), |
| diag::warn_header_guard) |
| << CurPPLexer->MIOpt.GetMacroLocation() |
| << ControllingMacro; |
| Diag(CurPPLexer->MIOpt.GetDefinedLocation(), |
| diag::note_header_guard) |
| << CurPPLexer->MIOpt.GetDefinedLocation() |
| << DefinedMacro |
| << ControllingMacro |
| << FixItHint::CreateReplacement( |
| CurPPLexer->MIOpt.GetDefinedLocation(), |
| ControllingMacro->getName()); |
| } |
| } |
| } |
| } |
| } |
| |
| // Complain about reaching a true EOF within arc_cf_code_audited. |
| // We don't want to complain about reaching the end of a macro |
| // instantiation or a _Pragma. |
| if (PragmaARCCFCodeAuditedLoc.isValid() && |
| !isEndOfMacro && !(CurLexer && CurLexer->Is_PragmaLexer)) { |
| Diag(PragmaARCCFCodeAuditedLoc, diag::err_pp_eof_in_arc_cf_code_audited); |
| |
| // Recover by leaving immediately. |
| PragmaARCCFCodeAuditedLoc = SourceLocation(); |
| } |
| |
| // If this is a #include'd file, pop it off the include stack and continue |
| // lexing the #includer file. |
| if (!IncludeMacroStack.empty()) { |
| |
| // If we lexed the code-completion file, act as if we reached EOF. |
| if (isCodeCompletionEnabled() && CurPPLexer && |
| SourceMgr.getLocForStartOfFile(CurPPLexer->getFileID()) == |
| CodeCompletionFileLoc) { |
| if (CurLexer) { |
| Result.startToken(); |
| CurLexer->FormTokenWithChars(Result, CurLexer->BufferEnd, tok::eof); |
| CurLexer.reset(); |
| } else { |
| assert(CurPTHLexer && "Got EOF but no current lexer set!"); |
| CurPTHLexer->getEOF(Result); |
| CurPTHLexer.reset(); |
| } |
| |
| CurPPLexer = 0; |
| return true; |
| } |
| |
| if (!isEndOfMacro && CurPPLexer && |
| SourceMgr.getIncludeLoc(CurPPLexer->getFileID()).isValid()) { |
| // Notify SourceManager to record the number of FileIDs that were created |
| // during lexing of the #include'd file. |
| unsigned NumFIDs = |
| SourceMgr.local_sloc_entry_size() - |
| CurPPLexer->getInitialNumSLocEntries() + 1/*#include'd file*/; |
| SourceMgr.setNumCreatedFIDsForFileID(CurPPLexer->getFileID(), NumFIDs); |
| } |
| |
| FileID ExitedFID; |
| if (Callbacks && !isEndOfMacro && CurPPLexer) |
| ExitedFID = CurPPLexer->getFileID(); |
| |
| // We're done with the #included file. |
| RemoveTopOfLexerStack(); |
| |
| // Notify the client, if desired, that we are in a new source file. |
| if (Callbacks && !isEndOfMacro && CurPPLexer) { |
| SrcMgr::CharacteristicKind FileType = |
| SourceMgr.getFileCharacteristic(CurPPLexer->getSourceLocation()); |
| Callbacks->FileChanged(CurPPLexer->getSourceLocation(), |
| PPCallbacks::ExitFile, FileType, ExitedFID); |
| } |
| |
| // Client should lex another token. |
| return false; |
| } |
| |
| // If the file ends with a newline, form the EOF token on the newline itself, |
| // rather than "on the line following it", which doesn't exist. This makes |
| // diagnostics relating to the end of file include the last file that the user |
| // actually typed, which is goodness. |
| if (CurLexer) { |
| const char *EndPos = CurLexer->BufferEnd; |
| if (EndPos != CurLexer->BufferStart && |
| (EndPos[-1] == '\n' || EndPos[-1] == '\r')) { |
| --EndPos; |
| |
| // Handle \n\r and \r\n: |
| if (EndPos != CurLexer->BufferStart && |
| (EndPos[-1] == '\n' || EndPos[-1] == '\r') && |
| EndPos[-1] != EndPos[0]) |
| --EndPos; |
| } |
| |
| Result.startToken(); |
| CurLexer->BufferPtr = EndPos; |
| CurLexer->FormTokenWithChars(Result, EndPos, tok::eof); |
| |
| if (isCodeCompletionEnabled()) { |
| // Inserting the code-completion point increases the source buffer by 1, |
| // but the main FileID was created before inserting the point. |
| // Compensate by reducing the EOF location by 1, otherwise the location |
| // will point to the next FileID. |
| // FIXME: This is hacky, the code-completion point should probably be |
| // inserted before the main FileID is created. |
| if (CurLexer->getFileLoc() == CodeCompletionFileLoc) |
| Result.setLocation(Result.getLocation().getLocWithOffset(-1)); |
| } |
| |
| if (!isIncrementalProcessingEnabled()) |
| // We're done with lexing. |
| CurLexer.reset(); |
| } else { |
| assert(CurPTHLexer && "Got EOF but no current lexer set!"); |
| CurPTHLexer->getEOF(Result); |
| CurPTHLexer.reset(); |
| } |
| |
| if (!isIncrementalProcessingEnabled()) |
| CurPPLexer = 0; |
| |
| // This is the end of the top-level file. 'WarnUnusedMacroLocs' has collected |
| // all macro locations that we need to warn because they are not used. |
| for (WarnUnusedMacroLocsTy::iterator |
| I=WarnUnusedMacroLocs.begin(), E=WarnUnusedMacroLocs.end(); I!=E; ++I) |
| Diag(*I, diag::pp_macro_not_used); |
| |
| // If we are building a module that has an umbrella header, make sure that |
| // each of the headers within the directory covered by the umbrella header |
| // was actually included by the umbrella header. |
| if (Module *Mod = getCurrentModule()) { |
| if (Mod->getUmbrellaHeader()) { |
| SourceLocation StartLoc |
| = SourceMgr.getLocForStartOfFile(SourceMgr.getMainFileID()); |
| |
| if (getDiagnostics().getDiagnosticLevel( |
| diag::warn_uncovered_module_header, |
| StartLoc) != DiagnosticsEngine::Ignored) { |
| ModuleMap &ModMap = getHeaderSearchInfo().getModuleMap(); |
| typedef llvm::sys::fs::recursive_directory_iterator |
| recursive_directory_iterator; |
| const DirectoryEntry *Dir = Mod->getUmbrellaDir(); |
| llvm::error_code EC; |
| for (recursive_directory_iterator Entry(Dir->getName(), EC), End; |
| Entry != End && !EC; Entry.increment(EC)) { |
| using llvm::StringSwitch; |
| |
| // Check whether this entry has an extension typically associated with |
| // headers. |
| if (!StringSwitch<bool>(llvm::sys::path::extension(Entry->path())) |
| .Cases(".h", ".H", ".hh", ".hpp", true) |
| .Default(false)) |
| continue; |
| |
| if (const FileEntry *Header = getFileManager().getFile(Entry->path())) |
| if (!getSourceManager().hasFileInfo(Header)) { |
| if (!ModMap.isHeaderInUnavailableModule(Header)) { |
| // Find the relative path that would access this header. |
| SmallString<128> RelativePath; |
| computeRelativePath(FileMgr, Dir, Header, RelativePath); |
| Diag(StartLoc, diag::warn_uncovered_module_header) |
| << Mod->getFullModuleName() << RelativePath; |
| } |
| } |
| } |
| } |
| } |
| |
| // Check whether there are any headers that were included, but not |
| // mentioned at all in the module map. Such headers |
| SourceLocation StartLoc |
| = SourceMgr.getLocForStartOfFile(SourceMgr.getMainFileID()); |
| if (getDiagnostics().getDiagnosticLevel(diag::warn_forgotten_module_header, |
| StartLoc) |
| != DiagnosticsEngine::Ignored) { |
| ModuleMap &ModMap = getHeaderSearchInfo().getModuleMap(); |
| for (unsigned I = 0, N = SourceMgr.local_sloc_entry_size(); I != N; ++I) { |
| // We only care about file entries. |
| const SrcMgr::SLocEntry &Entry = SourceMgr.getLocalSLocEntry(I); |
| if (!Entry.isFile()) |
| continue; |
| |
| // Dig out the actual file. |
| const FileEntry *File = Entry.getFile().getContentCache()->OrigEntry; |
| if (!File) |
| continue; |
| |
| // If it's not part of a module and not unknown, complain. |
| if (!ModMap.findModuleForHeader(File) && |
| !ModMap.isHeaderInUnavailableModule(File)) { |
| Diag(StartLoc, diag::warn_forgotten_module_header) |
| << File->getName() << Mod->getFullModuleName(); |
| } |
| } |
| } |
| } |
| |
| return true; |
| } |
| |
| /// HandleEndOfTokenLexer - This callback is invoked when the current TokenLexer |
| /// hits the end of its token stream. |
| bool Preprocessor::HandleEndOfTokenLexer(Token &Result) { |
| assert(CurTokenLexer && !CurPPLexer && |
| "Ending a macro when currently in a #include file!"); |
| |
| if (!MacroExpandingLexersStack.empty() && |
| MacroExpandingLexersStack.back().first == CurTokenLexer.get()) |
| removeCachedMacroExpandedTokensOfLastLexer(); |
| |
| // Delete or cache the now-dead macro expander. |
| if (NumCachedTokenLexers == TokenLexerCacheSize) |
| CurTokenLexer.reset(); |
| else |
| TokenLexerCache[NumCachedTokenLexers++] = CurTokenLexer.take(); |
| |
| // Handle this like a #include file being popped off the stack. |
| return HandleEndOfFile(Result, true); |
| } |
| |
| /// RemoveTopOfLexerStack - Pop the current lexer/macro exp off the top of the |
| /// lexer stack. This should only be used in situations where the current |
| /// state of the top-of-stack lexer is unknown. |
| void Preprocessor::RemoveTopOfLexerStack() { |
| assert(!IncludeMacroStack.empty() && "Ran out of stack entries to load"); |
| |
| if (CurTokenLexer) { |
| // Delete or cache the now-dead macro expander. |
| if (NumCachedTokenLexers == TokenLexerCacheSize) |
| CurTokenLexer.reset(); |
| else |
| TokenLexerCache[NumCachedTokenLexers++] = CurTokenLexer.take(); |
| } |
| |
| PopIncludeMacroStack(); |
| } |
| |
| /// HandleMicrosoftCommentPaste - When the macro expander pastes together a |
| /// comment (/##/) in microsoft mode, this method handles updating the current |
| /// state, returning the token on the next source line. |
| void Preprocessor::HandleMicrosoftCommentPaste(Token &Tok) { |
| assert(CurTokenLexer && !CurPPLexer && |
| "Pasted comment can only be formed from macro"); |
| |
| // We handle this by scanning for the closest real lexer, switching it to |
| // raw mode and preprocessor mode. This will cause it to return \n as an |
| // explicit EOD token. |
| PreprocessorLexer *FoundLexer = 0; |
| bool LexerWasInPPMode = false; |
| for (unsigned i = 0, e = IncludeMacroStack.size(); i != e; ++i) { |
| IncludeStackInfo &ISI = *(IncludeMacroStack.end()-i-1); |
| if (ISI.ThePPLexer == 0) continue; // Scan for a real lexer. |
| |
| // Once we find a real lexer, mark it as raw mode (disabling macro |
| // expansions) and preprocessor mode (return EOD). We know that the lexer |
| // was *not* in raw mode before, because the macro that the comment came |
| // from was expanded. However, it could have already been in preprocessor |
| // mode (#if COMMENT) in which case we have to return it to that mode and |
| // return EOD. |
| FoundLexer = ISI.ThePPLexer; |
| FoundLexer->LexingRawMode = true; |
| LexerWasInPPMode = FoundLexer->ParsingPreprocessorDirective; |
| FoundLexer->ParsingPreprocessorDirective = true; |
| break; |
| } |
| |
| // Okay, we either found and switched over the lexer, or we didn't find a |
| // lexer. In either case, finish off the macro the comment came from, getting |
| // the next token. |
| if (!HandleEndOfTokenLexer(Tok)) Lex(Tok); |
| |
| // Discarding comments as long as we don't have EOF or EOD. This 'comments |
| // out' the rest of the line, including any tokens that came from other macros |
| // that were active, as in: |
| // #define submacro a COMMENT b |
| // submacro c |
| // which should lex to 'a' only: 'b' and 'c' should be removed. |
| while (Tok.isNot(tok::eod) && Tok.isNot(tok::eof)) |
| Lex(Tok); |
| |
| // If we got an eod token, then we successfully found the end of the line. |
| if (Tok.is(tok::eod)) { |
| assert(FoundLexer && "Can't get end of line without an active lexer"); |
| // Restore the lexer back to normal mode instead of raw mode. |
| FoundLexer->LexingRawMode = false; |
| |
| // If the lexer was already in preprocessor mode, just return the EOD token |
| // to finish the preprocessor line. |
| if (LexerWasInPPMode) return; |
| |
| // Otherwise, switch out of PP mode and return the next lexed token. |
| FoundLexer->ParsingPreprocessorDirective = false; |
| return Lex(Tok); |
| } |
| |
| // If we got an EOF token, then we reached the end of the token stream but |
| // didn't find an explicit \n. This can only happen if there was no lexer |
| // active (an active lexer would return EOD at EOF if there was no \n in |
| // preprocessor directive mode), so just return EOF as our token. |
| assert(!FoundLexer && "Lexer should return EOD before EOF in PP mode"); |
| } |