499 lines · cpp
1//===-- HeaderIncludeGen.cpp - Generate Header Includes -------------------===//2//3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.4// See https://llvm.org/LICENSE.txt for license information.5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception6//7//===----------------------------------------------------------------------===//8 9#include "clang/Basic/DiagnosticFrontend.h"10#include "clang/Basic/SourceManager.h"11#include "clang/Frontend/DependencyOutputOptions.h"12#include "clang/Frontend/Utils.h"13#include "clang/Lex/Preprocessor.h"14#include "llvm/ADT/SmallString.h"15#include "llvm/Support/JSON.h"16#include "llvm/Support/raw_ostream.h"17using namespace clang;18 19namespace {20class HeaderIncludesCallback : public PPCallbacks {21 SourceManager &SM;22 raw_ostream *OutputFile;23 const DependencyOutputOptions &DepOpts;24 unsigned CurrentIncludeDepth;25 bool HasProcessedPredefines;26 bool OwnsOutputFile;27 bool ShowAllHeaders;28 bool ShowDepth;29 bool MSStyle;30 31public:32 HeaderIncludesCallback(const Preprocessor *PP, bool ShowAllHeaders_,33 raw_ostream *OutputFile_,34 const DependencyOutputOptions &DepOpts,35 bool OwnsOutputFile_, bool ShowDepth_, bool MSStyle_)36 : SM(PP->getSourceManager()), OutputFile(OutputFile_), DepOpts(DepOpts),37 CurrentIncludeDepth(0), HasProcessedPredefines(false),38 OwnsOutputFile(OwnsOutputFile_), ShowAllHeaders(ShowAllHeaders_),39 ShowDepth(ShowDepth_), MSStyle(MSStyle_) {}40 41 ~HeaderIncludesCallback() override {42 if (OwnsOutputFile)43 delete OutputFile;44 }45 46 HeaderIncludesCallback(const HeaderIncludesCallback &) = delete;47 HeaderIncludesCallback &operator=(const HeaderIncludesCallback &) = delete;48 49 void FileChanged(SourceLocation Loc, FileChangeReason Reason,50 SrcMgr::CharacteristicKind FileType,51 FileID PrevFID) override;52 53 void FileSkipped(const FileEntryRef &SkippedFile, const Token &FilenameTok,54 SrcMgr::CharacteristicKind FileType) override;55 56private:57 bool ShouldShowHeader(SrcMgr::CharacteristicKind HeaderType) {58 if (!DepOpts.IncludeSystemHeaders && isSystem(HeaderType))59 return false;60 61 // Show the current header if we are (a) past the predefines, or (b) showing62 // all headers and in the predefines at a depth past the initial file and63 // command line buffers.64 return (HasProcessedPredefines ||65 (ShowAllHeaders && CurrentIncludeDepth > 2));66 }67};68 69/// A callback for emitting header usage information to a file in JSON. Each70/// line in the file is a JSON object that includes the source file name and71/// the list of headers directly or indirectly included from it. For example:72///73/// {"source":"/tmp/foo.c",74/// "includes":["/usr/include/stdio.h", "/usr/include/stdlib.h"]}75///76/// To reduce the amount of data written to the file, we only record system77/// headers that are directly included from a file that isn't in the system78/// directory.79class HeaderIncludesJSONCallback : public PPCallbacks {80 SourceManager &SM;81 raw_ostream *OutputFile;82 bool OwnsOutputFile;83 SmallVector<std::string, 16> IncludedHeaders;84 85public:86 HeaderIncludesJSONCallback(const Preprocessor *PP, raw_ostream *OutputFile_,87 bool OwnsOutputFile_)88 : SM(PP->getSourceManager()), OutputFile(OutputFile_),89 OwnsOutputFile(OwnsOutputFile_) {}90 91 ~HeaderIncludesJSONCallback() override {92 if (OwnsOutputFile)93 delete OutputFile;94 }95 96 HeaderIncludesJSONCallback(const HeaderIncludesJSONCallback &) = delete;97 HeaderIncludesJSONCallback &98 operator=(const HeaderIncludesJSONCallback &) = delete;99 100 void EndOfMainFile() override;101 102 void FileChanged(SourceLocation Loc, FileChangeReason Reason,103 SrcMgr::CharacteristicKind FileType,104 FileID PrevFID) override;105 106 void FileSkipped(const FileEntryRef &SkippedFile, const Token &FilenameTok,107 SrcMgr::CharacteristicKind FileType) override;108};109 110/// A callback for emitting direct header and module usage information to a111/// file in JSON. The output format is like HeaderIncludesJSONCallback but has112/// an array of separate entries, one for each non-system source file used in113/// the compilation showing only the direct includes and imports from that file.114class HeaderIncludesDirectPerFileCallback : public PPCallbacks {115 struct HeaderIncludeInfo {116 SourceLocation Location;117 FileEntryRef File;118 const Module *ImportedModule;119 120 HeaderIncludeInfo(SourceLocation Location, FileEntryRef File,121 const Module *ImportedModule)122 : Location(Location), File(File), ImportedModule(ImportedModule) {}123 };124 125 SourceManager &SM;126 HeaderSearch &HSI;127 raw_ostream *OutputFile;128 bool OwnsOutputFile;129 using DependencyMap =130 llvm::DenseMap<FileEntryRef, SmallVector<HeaderIncludeInfo>>;131 DependencyMap Dependencies;132 133public:134 HeaderIncludesDirectPerFileCallback(const Preprocessor *PP,135 raw_ostream *OutputFile_,136 bool OwnsOutputFile_)137 : SM(PP->getSourceManager()), HSI(PP->getHeaderSearchInfo()),138 OutputFile(OutputFile_), OwnsOutputFile(OwnsOutputFile_) {}139 140 ~HeaderIncludesDirectPerFileCallback() override {141 if (OwnsOutputFile)142 delete OutputFile;143 }144 145 HeaderIncludesDirectPerFileCallback(146 const HeaderIncludesDirectPerFileCallback &) = delete;147 HeaderIncludesDirectPerFileCallback &148 operator=(const HeaderIncludesDirectPerFileCallback &) = delete;149 150 void EndOfMainFile() override;151 152 void InclusionDirective(SourceLocation HashLoc, const Token &IncludeTok,153 StringRef FileName, bool IsAngled,154 CharSourceRange FilenameRange,155 OptionalFileEntryRef File, StringRef SearchPath,156 StringRef RelativePath, const Module *SuggestedModule,157 bool ModuleImported,158 SrcMgr::CharacteristicKind FileType) override;159 160 void moduleImport(SourceLocation ImportLoc, ModuleIdPath Path,161 const Module *Imported) override;162};163}164 165static void PrintHeaderInfo(raw_ostream *OutputFile, StringRef Filename,166 bool ShowDepth, unsigned CurrentIncludeDepth,167 bool MSStyle) {168 // Write to a temporary string to avoid unnecessary flushing on errs().169 SmallString<512> Pathname(Filename);170 if (!MSStyle)171 Lexer::Stringify(Pathname);172 173 SmallString<256> Msg;174 if (MSStyle)175 Msg += "Note: including file:";176 177 if (ShowDepth) {178 // The main source file is at depth 1, so skip one dot.179 for (unsigned i = 1; i != CurrentIncludeDepth; ++i)180 Msg += MSStyle ? ' ' : '.';181 182 if (!MSStyle)183 Msg += ' ';184 }185 Msg += Pathname;186 Msg += '\n';187 188 *OutputFile << Msg;189 OutputFile->flush();190}191 192void clang::AttachHeaderIncludeGen(Preprocessor &PP,193 const DependencyOutputOptions &DepOpts,194 bool ShowAllHeaders, StringRef OutputPath,195 bool ShowDepth, bool MSStyle) {196 raw_ostream *OutputFile = &llvm::errs();197 bool OwnsOutputFile = false;198 199 // Choose output stream, when printing in cl.exe /showIncludes style.200 if (MSStyle) {201 switch (DepOpts.ShowIncludesDest) {202 default:203 llvm_unreachable("Invalid destination for /showIncludes output!");204 case ShowIncludesDestination::Stderr:205 OutputFile = &llvm::errs();206 break;207 case ShowIncludesDestination::Stdout:208 OutputFile = &llvm::outs();209 break;210 }211 }212 213 // Open the output file, if used.214 if (!OutputPath.empty()) {215 std::error_code EC;216 llvm::raw_fd_ostream *OS = new llvm::raw_fd_ostream(217 OutputPath.str(), EC,218 llvm::sys::fs::OF_Append | llvm::sys::fs::OF_TextWithCRLF);219 if (EC) {220 PP.getDiagnostics().Report(clang::diag::warn_fe_cc_print_header_failure)221 << EC.message();222 delete OS;223 } else {224 OS->SetUnbuffered();225 OutputFile = OS;226 OwnsOutputFile = true;227 }228 }229 230 switch (DepOpts.HeaderIncludeFormat) {231 case HIFMT_None:232 llvm_unreachable("unexpected header format kind");233 case HIFMT_Textual: {234 assert(DepOpts.HeaderIncludeFiltering == HIFIL_None &&235 "header filtering is currently always disabled when output format is"236 "textual");237 // Print header info for extra headers, pretending they were discovered by238 // the regular preprocessor. The primary use case is to support proper239 // generation of Make / Ninja file dependencies for implicit includes, such240 // as sanitizer ignorelists. It's only important for cl.exe compatibility,241 // the GNU way to generate rules is -M / -MM / -MD / -MMD.242 for (const auto &Header : DepOpts.ExtraDeps)243 PrintHeaderInfo(OutputFile, Header.first, ShowDepth, 2, MSStyle);244 PP.addPPCallbacks(std::make_unique<HeaderIncludesCallback>(245 &PP, ShowAllHeaders, OutputFile, DepOpts, OwnsOutputFile, ShowDepth,246 MSStyle));247 break;248 }249 case HIFMT_JSON:250 switch (DepOpts.HeaderIncludeFiltering) {251 default:252 llvm_unreachable("Unknown HeaderIncludeFilteringKind enum");253 case HIFIL_Only_Direct_System:254 PP.addPPCallbacks(std::make_unique<HeaderIncludesJSONCallback>(255 &PP, OutputFile, OwnsOutputFile));256 break;257 case HIFIL_Direct_Per_File:258 PP.addPPCallbacks(std::make_unique<HeaderIncludesDirectPerFileCallback>(259 &PP, OutputFile, OwnsOutputFile));260 break;261 }262 break;263 }264}265 266void HeaderIncludesCallback::FileChanged(SourceLocation Loc,267 FileChangeReason Reason,268 SrcMgr::CharacteristicKind NewFileType,269 FileID PrevFID) {270 // Unless we are exiting a #include, make sure to skip ahead to the line the271 // #include directive was at.272 PresumedLoc UserLoc = SM.getPresumedLoc(Loc);273 if (UserLoc.isInvalid())274 return;275 276 // Adjust the current include depth.277 if (Reason == PPCallbacks::EnterFile) {278 ++CurrentIncludeDepth;279 } else if (Reason == PPCallbacks::ExitFile) {280 if (CurrentIncludeDepth)281 --CurrentIncludeDepth;282 283 // We track when we are done with the predefines by watching for the first284 // place where we drop back to a nesting depth of 1.285 if (CurrentIncludeDepth == 1 && !HasProcessedPredefines)286 HasProcessedPredefines = true;287 288 return;289 } else {290 return;291 }292 293 if (!ShouldShowHeader(NewFileType))294 return;295 296 unsigned IncludeDepth = CurrentIncludeDepth;297 if (!HasProcessedPredefines)298 --IncludeDepth; // Ignore indent from <built-in>.299 300 // FIXME: Identify headers in a more robust way than comparing their name to301 // "<command line>" and "<built-in>" in a bunch of places.302 if (Reason == PPCallbacks::EnterFile &&303 UserLoc.getFilename() != StringRef("<command line>")) {304 PrintHeaderInfo(OutputFile, UserLoc.getFilename(), ShowDepth, IncludeDepth,305 MSStyle);306 }307}308 309void HeaderIncludesCallback::FileSkipped(const FileEntryRef &SkippedFile,310 const Token &FilenameTok,311 SrcMgr::CharacteristicKind FileType) {312 if (!DepOpts.ShowSkippedHeaderIncludes)313 return;314 315 if (!ShouldShowHeader(FileType))316 return;317 318 PrintHeaderInfo(OutputFile, SkippedFile.getName(), ShowDepth,319 CurrentIncludeDepth + 1, MSStyle);320}321 322void HeaderIncludesJSONCallback::EndOfMainFile() {323 OptionalFileEntryRef FE = SM.getFileEntryRefForID(SM.getMainFileID());324 SmallString<256> MainFile;325 if (FE) {326 MainFile += FE->getName();327 SM.getFileManager().makeAbsolutePath(MainFile);328 }329 330 std::string Str;331 llvm::raw_string_ostream OS(Str);332 llvm::json::OStream JOS(OS);333 JOS.object([&] {334 JOS.attribute("source", MainFile.c_str());335 JOS.attributeArray("includes", [&] {336 llvm::StringSet<> SeenHeaders;337 for (const std::string &H : IncludedHeaders)338 if (SeenHeaders.insert(H).second)339 JOS.value(H);340 });341 });342 OS << "\n";343 344 if (OutputFile->get_kind() == raw_ostream::OStreamKind::OK_FDStream) {345 llvm::raw_fd_ostream *FDS = static_cast<llvm::raw_fd_ostream *>(OutputFile);346 if (auto L = FDS->lock())347 *OutputFile << Str;348 } else349 *OutputFile << Str;350}351 352/// Determine whether the header file should be recorded. The header file should353/// be recorded only if the header file is a system header and the current file354/// isn't a system header.355static bool shouldRecordNewFile(SrcMgr::CharacteristicKind NewFileType,356 SourceLocation PrevLoc, SourceManager &SM) {357 return SrcMgr::isSystem(NewFileType) && !SM.isInSystemHeader(PrevLoc);358}359 360void HeaderIncludesJSONCallback::FileChanged(361 SourceLocation Loc, FileChangeReason Reason,362 SrcMgr::CharacteristicKind NewFileType, FileID PrevFID) {363 if (PrevFID.isInvalid() ||364 !shouldRecordNewFile(NewFileType, SM.getLocForStartOfFile(PrevFID), SM))365 return;366 367 // Unless we are exiting a #include, make sure to skip ahead to the line the368 // #include directive was at.369 PresumedLoc UserLoc = SM.getPresumedLoc(Loc);370 if (UserLoc.isInvalid())371 return;372 373 if (Reason == PPCallbacks::EnterFile &&374 UserLoc.getFilename() != StringRef("<command line>"))375 IncludedHeaders.push_back(UserLoc.getFilename());376}377 378void HeaderIncludesJSONCallback::FileSkipped(379 const FileEntryRef &SkippedFile, const Token &FilenameTok,380 SrcMgr::CharacteristicKind FileType) {381 if (!shouldRecordNewFile(FileType, FilenameTok.getLocation(), SM))382 return;383 384 IncludedHeaders.push_back(SkippedFile.getName().str());385}386 387void HeaderIncludesDirectPerFileCallback::EndOfMainFile() {388 if (Dependencies.empty())389 return;390 391 // Sort the files so that the output does not depend on the DenseMap order.392 SmallVector<FileEntryRef> SourceFiles;393 for (auto F = Dependencies.begin(), FEnd = Dependencies.end(); F != FEnd;394 ++F) {395 SourceFiles.push_back(F->first);396 }397 llvm::sort(SourceFiles, [](const FileEntryRef &LHS, const FileEntryRef &RHS) {398 return LHS.getUID() < RHS.getUID();399 });400 401 std::string Str;402 llvm::raw_string_ostream OS(Str);403 llvm::json::OStream JOS(OS);404 JOS.object([&] {405 JOS.attribute("version", "2.0.0");406 JOS.attributeArray("dependencies", [&] {407 for (const auto &S : SourceFiles) {408 JOS.object([&] {409 SmallVector<HeaderIncludeInfo> &Deps = Dependencies[S];410 JOS.attribute("source", S.getName().str());411 JOS.attributeArray("includes", [&] {412 for (unsigned I = 0, N = Deps.size(); I != N; ++I) {413 if (!Deps[I].ImportedModule) {414 JOS.object([&] {415 JOS.attribute("location", Deps[I].Location.printToString(SM));416 JOS.attribute("file", Deps[I].File.getName());417 });418 }419 }420 });421 JOS.attributeArray("imports", [&] {422 for (unsigned I = 0, N = Deps.size(); I != N; ++I) {423 if (Deps[I].ImportedModule) {424 JOS.object([&] {425 JOS.attribute("location", Deps[I].Location.printToString(SM));426 JOS.attribute(427 "module",428 Deps[I].ImportedModule->getTopLevelModuleName());429 JOS.attribute("file", Deps[I].File.getName());430 });431 }432 }433 });434 });435 }436 });437 });438 439 OS << "\n";440 441 if (OutputFile->get_kind() == raw_ostream::OStreamKind::OK_FDStream) {442 llvm::raw_fd_ostream *FDS = static_cast<llvm::raw_fd_ostream *>(OutputFile);443 if (auto L = FDS->lock())444 *OutputFile << Str;445 } else446 *OutputFile << Str;447}448 449void HeaderIncludesDirectPerFileCallback::InclusionDirective(450 SourceLocation HashLoc, const Token &IncludeTok, StringRef FileName,451 bool IsAngled, CharSourceRange FilenameRange, OptionalFileEntryRef File,452 StringRef SearchPath, StringRef RelativePath, const Module *SuggestedModule,453 bool ModuleImported, SrcMgr::CharacteristicKind FileType) {454 if (!File)455 return;456 457 SourceLocation Loc = SM.getExpansionLoc(HashLoc);458 if (SM.isInSystemHeader(Loc))459 return;460 OptionalFileEntryRef FromFile = SM.getFileEntryRefForID(SM.getFileID(Loc));461 if (!FromFile)462 return;463 464 FileEntryRef HeaderOrModuleMapFile = *File;465 if (ModuleImported && SuggestedModule) {466 OptionalFileEntryRef ModuleMapFile =467 HSI.getModuleMap().getModuleMapFileForUniquing(SuggestedModule);468 if (ModuleMapFile) {469 HeaderOrModuleMapFile = *ModuleMapFile;470 }471 }472 473 HeaderIncludeInfo DependenciesEntry(474 Loc, HeaderOrModuleMapFile, (ModuleImported ? SuggestedModule : nullptr));475 Dependencies[*FromFile].push_back(DependenciesEntry);476}477 478void HeaderIncludesDirectPerFileCallback::moduleImport(SourceLocation ImportLoc,479 ModuleIdPath Path,480 const Module *Imported) {481 if (!Imported)482 return;483 484 SourceLocation Loc = SM.getExpansionLoc(ImportLoc);485 if (SM.isInSystemHeader(Loc))486 return;487 OptionalFileEntryRef FromFile = SM.getFileEntryRefForID(SM.getFileID(Loc));488 if (!FromFile)489 return;490 491 OptionalFileEntryRef ModuleMapFile =492 HSI.getModuleMap().getModuleMapFileForUniquing(Imported);493 if (!ModuleMapFile)494 return;495 496 HeaderIncludeInfo DependenciesEntry(Loc, *ModuleMapFile, Imported);497 Dependencies[*FromFile].push_back(DependenciesEntry);498}499