| //===-- HeaderIncludeGen.cpp - Generate Header Includes -------------------===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "clang/Frontend/DependencyOutputOptions.h" |
| #include "clang/Frontend/Utils.h" |
| #include "clang/Basic/SourceManager.h" |
| #include "clang/Frontend/FrontendDiagnostic.h" |
| #include "clang/Lex/Preprocessor.h" |
| #include "llvm/ADT/SmallString.h" |
| #include "llvm/Support/raw_ostream.h" |
| using namespace clang; |
| |
| namespace { |
| class HeaderIncludesCallback : public PPCallbacks { |
| SourceManager &SM; |
| raw_ostream *OutputFile; |
| const DependencyOutputOptions &DepOpts; |
| unsigned CurrentIncludeDepth; |
| bool HasProcessedPredefines; |
| bool OwnsOutputFile; |
| bool ShowAllHeaders; |
| bool ShowDepth; |
| bool MSStyle; |
| |
| public: |
| HeaderIncludesCallback(const Preprocessor *PP, bool ShowAllHeaders_, |
| raw_ostream *OutputFile_, |
| const DependencyOutputOptions &DepOpts, |
| bool OwnsOutputFile_, bool ShowDepth_, bool MSStyle_) |
| : SM(PP->getSourceManager()), OutputFile(OutputFile_), DepOpts(DepOpts), |
| CurrentIncludeDepth(0), HasProcessedPredefines(false), |
| OwnsOutputFile(OwnsOutputFile_), ShowAllHeaders(ShowAllHeaders_), |
| ShowDepth(ShowDepth_), MSStyle(MSStyle_) {} |
| |
| ~HeaderIncludesCallback() override { |
| if (OwnsOutputFile) |
| delete OutputFile; |
| } |
| |
| void FileChanged(SourceLocation Loc, FileChangeReason Reason, |
| SrcMgr::CharacteristicKind FileType, |
| FileID PrevFID) override; |
| }; |
| } |
| |
| static void PrintHeaderInfo(raw_ostream *OutputFile, StringRef Filename, |
| bool ShowDepth, unsigned CurrentIncludeDepth, |
| bool MSStyle) { |
| // Write to a temporary string to avoid unnecessary flushing on errs(). |
| SmallString<512> Pathname(Filename); |
| if (!MSStyle) |
| Lexer::Stringify(Pathname); |
| |
| SmallString<256> Msg; |
| if (MSStyle) |
| Msg += "Note: including file:"; |
| |
| if (ShowDepth) { |
| // The main source file is at depth 1, so skip one dot. |
| for (unsigned i = 1; i != CurrentIncludeDepth; ++i) |
| Msg += MSStyle ? ' ' : '.'; |
| |
| if (!MSStyle) |
| Msg += ' '; |
| } |
| Msg += Pathname; |
| Msg += '\n'; |
| |
| *OutputFile << Msg; |
| OutputFile->flush(); |
| } |
| |
| void clang::AttachHeaderIncludeGen(Preprocessor &PP, |
| const DependencyOutputOptions &DepOpts, |
| bool ShowAllHeaders, StringRef OutputPath, |
| bool ShowDepth, bool MSStyle) { |
| raw_ostream *OutputFile = &llvm::errs(); |
| bool OwnsOutputFile = false; |
| |
| // Choose output stream, when printing in cl.exe /showIncludes style. |
| if (MSStyle) { |
| switch (DepOpts.ShowIncludesDest) { |
| default: |
| llvm_unreachable("Invalid destination for /showIncludes output!"); |
| case ShowIncludesDestination::Stderr: |
| OutputFile = &llvm::errs(); |
| break; |
| case ShowIncludesDestination::Stdout: |
| OutputFile = &llvm::outs(); |
| break; |
| } |
| } |
| |
| // Open the output file, if used. |
| if (!OutputPath.empty()) { |
| std::error_code EC; |
| llvm::raw_fd_ostream *OS = new llvm::raw_fd_ostream( |
| OutputPath.str(), EC, |
| llvm::sys::fs::OF_Append | llvm::sys::fs::OF_Text); |
| if (EC) { |
| PP.getDiagnostics().Report(clang::diag::warn_fe_cc_print_header_failure) |
| << EC.message(); |
| delete OS; |
| } else { |
| OS->SetUnbuffered(); |
| OutputFile = OS; |
| OwnsOutputFile = true; |
| } |
| } |
| |
| // Print header info for extra headers, pretending they were discovered by |
| // the regular preprocessor. The primary use case is to support proper |
| // generation of Make / Ninja file dependencies for implicit includes, such |
| // as sanitizer blacklists. It's only important for cl.exe compatibility, |
| // the GNU way to generate rules is -M / -MM / -MD / -MMD. |
| for (const auto &Header : DepOpts.ExtraDeps) |
| PrintHeaderInfo(OutputFile, Header, ShowDepth, 2, MSStyle); |
| PP.addPPCallbacks(std::make_unique<HeaderIncludesCallback>( |
| &PP, ShowAllHeaders, OutputFile, DepOpts, OwnsOutputFile, ShowDepth, |
| MSStyle)); |
| } |
| |
| void HeaderIncludesCallback::FileChanged(SourceLocation Loc, |
| FileChangeReason Reason, |
| SrcMgr::CharacteristicKind NewFileType, |
| FileID PrevFID) { |
| // Unless we are exiting a #include, make sure to skip ahead to the line the |
| // #include directive was at. |
| PresumedLoc UserLoc = SM.getPresumedLoc(Loc); |
| if (UserLoc.isInvalid()) |
| return; |
| |
| // Adjust the current include depth. |
| if (Reason == PPCallbacks::EnterFile) { |
| ++CurrentIncludeDepth; |
| } else if (Reason == PPCallbacks::ExitFile) { |
| if (CurrentIncludeDepth) |
| --CurrentIncludeDepth; |
| |
| // We track when we are done with the predefines by watching for the first |
| // place where we drop back to a nesting depth of 1. |
| if (CurrentIncludeDepth == 1 && !HasProcessedPredefines) { |
| if (!DepOpts.ShowIncludesPretendHeader.empty()) { |
| PrintHeaderInfo(OutputFile, DepOpts.ShowIncludesPretendHeader, |
| ShowDepth, 2, MSStyle); |
| } |
| HasProcessedPredefines = true; |
| } |
| |
| return; |
| } else |
| return; |
| |
| // Show the header if we are (a) past the predefines, or (b) showing all |
| // headers and in the predefines at a depth past the initial file and command |
| // line buffers. |
| bool ShowHeader = (HasProcessedPredefines || |
| (ShowAllHeaders && CurrentIncludeDepth > 2)); |
| unsigned IncludeDepth = CurrentIncludeDepth; |
| if (!HasProcessedPredefines) |
| --IncludeDepth; // Ignore indent from <built-in>. |
| else if (!DepOpts.ShowIncludesPretendHeader.empty()) |
| ++IncludeDepth; // Pretend inclusion by ShowIncludesPretendHeader. |
| |
| if (!DepOpts.IncludeSystemHeaders && isSystem(NewFileType)) |
| ShowHeader = false; |
| |
| // Dump the header include information we are past the predefines buffer or |
| // are showing all headers and this isn't the magic implicit <command line> |
| // header. |
| // FIXME: Identify headers in a more robust way than comparing their name to |
| // "<command line>" and "<built-in>" in a bunch of places. |
| if (ShowHeader && Reason == PPCallbacks::EnterFile && |
| UserLoc.getFilename() != StringRef("<command line>")) { |
| PrintHeaderInfo(OutputFile, UserLoc.getFilename(), ShowDepth, IncludeDepth, |
| MSStyle); |
| } |
| } |