llvm-project/clang-tools-extra/clangd/Headers.cpp

126 lines
4.7 KiB
C++

//===--- Headers.cpp - Include headers ---------------------------*- C++-*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "Headers.h"
#include "Compiler.h"
#include "Logger.h"
#include "clang/Frontend/CompilerInstance.h"
#include "clang/Frontend/CompilerInvocation.h"
#include "clang/Frontend/FrontendActions.h"
#include "clang/Lex/HeaderSearch.h"
#include "clang/Lex/PreprocessorOptions.h"
#include "clang/Tooling/CompilationDatabase.h"
#include "llvm/Support/Path.h"
namespace clang {
namespace clangd {
namespace {
class RecordHeaders : public PPCallbacks {
public:
RecordHeaders(std::set<std::string> &Headers) : Headers(Headers) {}
void InclusionDirective(SourceLocation /*HashLoc*/,
const Token & /*IncludeTok*/,
llvm::StringRef /*FileName*/, bool /*IsAngled*/,
CharSourceRange /*FilenameRange*/,
const FileEntry *File, llvm::StringRef /*SearchPath*/,
llvm::StringRef /*RelativePath*/,
const Module * /*Imported*/) override {
if (File != nullptr && !File->tryGetRealPathName().empty())
Headers.insert(File->tryGetRealPathName());
}
private:
std::set<std::string> &Headers;
};
} // namespace
/// FIXME(ioeric): we might not want to insert an absolute include path if the
/// path is not shortened.
llvm::Expected<std::string>
calculateIncludePath(llvm::StringRef File, llvm::StringRef Code,
llvm::StringRef Header,
const tooling::CompileCommand &CompileCommand,
IntrusiveRefCntPtr<vfs::FileSystem> FS) {
assert(llvm::sys::path::is_absolute(File) &&
llvm::sys::path::is_absolute(Header));
if (File == Header)
return "";
FS->setCurrentWorkingDirectory(CompileCommand.Directory);
// Set up a CompilerInstance and create a preprocessor to collect existing
// #include headers in \p Code. Preprocesor also provides HeaderSearch with
// which we can calculate the shortest include path for \p Header.
std::vector<const char *> Argv;
for (const auto &S : CompileCommand.CommandLine)
Argv.push_back(S.c_str());
IgnoringDiagConsumer IgnoreDiags;
auto CI = clang::createInvocationFromCommandLine(
Argv,
CompilerInstance::createDiagnostics(new DiagnosticOptions(), &IgnoreDiags,
false),
FS);
if (!CI)
return llvm::make_error<llvm::StringError>(
"Failed to create a compiler instance for " + File,
llvm::inconvertibleErrorCode());
CI->getFrontendOpts().DisableFree = false;
// Parse the main file to get all existing #includes in the file, and then we
// can make sure the same header (even with different include path) is not
// added more than once.
CI->getPreprocessorOpts().SingleFileParseMode = true;
auto Clang = prepareCompilerInstance(
std::move(CI), /*Preamble=*/nullptr,
llvm::MemoryBuffer::getMemBuffer(Code, File),
std::make_shared<PCHContainerOperations>(), FS, IgnoreDiags);
auto &DiagOpts = Clang->getDiagnosticOpts();
DiagOpts.IgnoreWarnings = true;
if (Clang->getFrontendOpts().Inputs.empty())
return llvm::make_error<llvm::StringError>(
"Empty frontend action inputs empty for file " + File,
llvm::inconvertibleErrorCode());
PreprocessOnlyAction Action;
if (!Action.BeginSourceFile(*Clang, Clang->getFrontendOpts().Inputs[0]))
return llvm::make_error<llvm::StringError>(
"Failed to begin preprocessor only action for file " + File,
llvm::inconvertibleErrorCode());
std::set<std::string> ExistingHeaders;
Clang->getPreprocessor().addPPCallbacks(
llvm::make_unique<RecordHeaders>(ExistingHeaders));
if (!Action.Execute())
return llvm::make_error<llvm::StringError>(
"Failed to execute preprocessor only action for file " + File,
llvm::inconvertibleErrorCode());
if (ExistingHeaders.find(Header) != ExistingHeaders.end()) {
return llvm::make_error<llvm::StringError>(
Header + " is already included in " + File,
llvm::inconvertibleErrorCode());
}
auto &HeaderSearchInfo = Clang->getPreprocessor().getHeaderSearchInfo();
bool IsSystem = false;
std::string Suggested = HeaderSearchInfo.suggestPathToFileForDiagnostics(
Header, CompileCommand.Directory, &IsSystem);
if (IsSystem)
Suggested = "<" + Suggested + ">";
else
Suggested = "\"" + Suggested + "\"";
log("Suggested #include for " + Header + " is: " + Suggested);
return Suggested;
}
} // namespace clangd
} // namespace clang