1 //===--- HeaderIncludes.cpp - Generate Header Includes --------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #include "clang/Frontend/Utils.h"
11 #include "clang/Basic/SourceManager.h"
12 #include "clang/Frontend/FrontendDiagnostic.h"
13 #include "clang/Lex/Preprocessor.h"
14 #include "llvm/ADT/SmallString.h"
15 #include "llvm/Support/raw_ostream.h"
16 using namespace clang;
19 class HeaderIncludesCallback : public PPCallbacks {
21 raw_ostream *OutputFile;
22 unsigned CurrentIncludeDepth;
23 bool HasProcessedPredefines;
30 HeaderIncludesCallback(const Preprocessor *PP, bool ShowAllHeaders_,
31 raw_ostream *OutputFile_, bool OwnsOutputFile_,
32 bool ShowDepth_, bool MSStyle_)
33 : SM(PP->getSourceManager()), OutputFile(OutputFile_),
34 CurrentIncludeDepth(0), HasProcessedPredefines(false),
35 OwnsOutputFile(OwnsOutputFile_), ShowAllHeaders(ShowAllHeaders_),
36 ShowDepth(ShowDepth_), MSStyle(MSStyle_) {}
38 ~HeaderIncludesCallback() override {
43 void FileChanged(SourceLocation Loc, FileChangeReason Reason,
44 SrcMgr::CharacteristicKind FileType,
45 FileID PrevFID) override;
49 void clang::AttachHeaderIncludeGen(Preprocessor &PP, bool ShowAllHeaders,
50 StringRef OutputPath, bool ShowDepth,
52 raw_ostream *OutputFile = MSStyle ? &llvm::outs() : &llvm::errs();
53 bool OwnsOutputFile = false;
55 // Open the output file, if used.
56 if (!OutputPath.empty()) {
58 llvm::raw_fd_ostream *OS = new llvm::raw_fd_ostream(
59 OutputPath.str(), EC, llvm::sys::fs::F_Append | llvm::sys::fs::F_Text);
61 PP.getDiagnostics().Report(clang::diag::warn_fe_cc_print_header_failure)
66 OS->SetUseAtomicWrites(true);
68 OwnsOutputFile = true;
72 PP.addPPCallbacks(llvm::make_unique<HeaderIncludesCallback>(&PP,
80 void HeaderIncludesCallback::FileChanged(SourceLocation Loc,
81 FileChangeReason Reason,
82 SrcMgr::CharacteristicKind NewFileType,
84 // Unless we are exiting a #include, make sure to skip ahead to the line the
85 // #include directive was at.
86 PresumedLoc UserLoc = SM.getPresumedLoc(Loc);
87 if (UserLoc.isInvalid())
90 // Adjust the current include depth.
91 if (Reason == PPCallbacks::EnterFile) {
92 ++CurrentIncludeDepth;
93 } else if (Reason == PPCallbacks::ExitFile) {
94 if (CurrentIncludeDepth)
95 --CurrentIncludeDepth;
97 // We track when we are done with the predefines by watching for the first
98 // place where we drop back to a nesting depth of 1.
99 if (CurrentIncludeDepth == 1 && !HasProcessedPredefines)
100 HasProcessedPredefines = true;
106 // Show the header if we are (a) past the predefines, or (b) showing all
107 // headers and in the predefines at a depth past the initial file and command
109 bool ShowHeader = (HasProcessedPredefines ||
110 (ShowAllHeaders && CurrentIncludeDepth > 2));
112 // Dump the header include information we are past the predefines buffer or
113 // are showing all headers.
114 if (ShowHeader && Reason == PPCallbacks::EnterFile) {
115 // Write to a temporary string to avoid unnecessary flushing on errs().
116 SmallString<512> Filename(UserLoc.getFilename());
118 Lexer::Stringify(Filename);
120 SmallString<256> Msg;
122 Msg += "Note: including file:";
125 // The main source file is at depth 1, so skip one dot.
126 for (unsigned i = 1; i != CurrentIncludeDepth; ++i)
127 Msg += MSStyle ? ' ' : '.';
135 OutputFile->write(Msg.data(), Msg.size());