159 lines · cpp
1//===-- CppModuleConfiguration.cpp ----------------------------------------===//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 "CppModuleConfiguration.h"10 11#include "ClangHost.h"12#include "lldb/Host/FileSystem.h"13#include "llvm/TargetParser/Triple.h"14#include <optional>15 16using namespace lldb_private;17 18bool CppModuleConfiguration::SetOncePath::TrySet(llvm::StringRef path) {19 // Setting for the first time always works.20 if (m_first) {21 m_path = path.str();22 m_valid = true;23 m_first = false;24 return true;25 }26 // Changing the path to the same value is fine.27 if (m_path == path)28 return true;29 30 // Changing the path after it was already set is not allowed.31 m_valid = false;32 return false;33}34 35static llvm::SmallVector<std::string, 2>36getTargetIncludePaths(const llvm::Triple &triple) {37 llvm::SmallVector<std::string, 2> paths;38 if (!triple.str().empty()) {39 paths.push_back("/usr/include/" + triple.str());40 if (!triple.getArchName().empty() ||41 triple.getOSAndEnvironmentName().empty())42 paths.push_back(("/usr/include/" + triple.getArchName() + "-" +43 triple.getOSAndEnvironmentName())44 .str());45 }46 return paths;47}48 49/// Returns the include path matching the given pattern for the given file50/// path (or std::nullopt if the path doesn't match the pattern).51static std::optional<llvm::StringRef>52guessIncludePath(llvm::StringRef path_to_file, llvm::StringRef pattern) {53 if (pattern.empty())54 return std::nullopt;55 size_t pos = path_to_file.find(pattern);56 if (pos == llvm::StringRef::npos)57 return std::nullopt;58 59 return path_to_file.substr(0, pos + pattern.size());60}61 62bool CppModuleConfiguration::analyzeFile(const FileSpec &f,63 const llvm::Triple &triple) {64 using namespace llvm::sys::path;65 // Convert to slashes to make following operations simpler.66 std::string dir_buffer = convert_to_slash(f.GetDirectory().GetStringRef());67 llvm::StringRef posix_dir(dir_buffer);68 69 // Check for /c++/vX/ that is used by libc++.70 static llvm::Regex libcpp_regex(R"regex(/c[+][+]/v[0-9]/)regex");71 // If the path is in the libc++ include directory use it as the found libc++72 // path. Ignore subdirectories such as /c++/v1/experimental as those don't73 // need to be specified in the header search.74 if (libcpp_regex.match(convert_to_slash(f.GetPath())) &&75 parent_path(posix_dir, Style::posix).ends_with("c++")) {76 if (!m_std_inc.TrySet(posix_dir))77 return false;78 if (triple.str().empty())79 return true;80 81 posix_dir.consume_back("c++/v1");82 // Check if this is a target-specific libc++ include directory.83 return m_std_target_inc.TrySet(84 (posix_dir + triple.str() + "/c++/v1").str());85 }86 87 std::optional<llvm::StringRef> inc_path;88 // Target specific paths contains /usr/include, so we check them first89 for (auto &path : getTargetIncludePaths(triple)) {90 if ((inc_path = guessIncludePath(posix_dir, path)))91 return m_c_target_inc.TrySet(*inc_path);92 }93 if ((inc_path = guessIncludePath(posix_dir, "/usr/include")))94 return m_c_inc.TrySet(*inc_path);95 96 // File wasn't interesting, continue analyzing.97 return true;98}99 100/// Utility function for just appending two paths.101static std::string MakePath(llvm::StringRef lhs, llvm::StringRef rhs) {102 llvm::SmallString<256> result(lhs);103 llvm::sys::path::append(result, rhs);104 return std::string(result);105}106 107bool CppModuleConfiguration::hasValidConfig() {108 // We need to have a C and C++ include dir for a valid configuration.109 if (!m_c_inc.Valid() || !m_std_inc.Valid())110 return false;111 112 // Do some basic sanity checks on the directories that we don't activate113 // the module when it's clear that it's not usable.114 const std::vector<std::string> files_to_check = {115 // * Check that the C library contains at least one random C standard116 // library header.117 MakePath(m_c_inc.Get(), "stdio.h"),118 // * Without a libc++ modulemap file we can't have a 'std' module that119 // could be imported.120 MakePath(m_std_inc.Get(), "module.modulemap"),121 // * Check for a random libc++ header (vector in this case) that has to122 // exist in a working libc++ setup.123 MakePath(m_std_inc.Get(), "vector"),124 };125 126 for (llvm::StringRef file_to_check : files_to_check) {127 if (!FileSystem::Instance().Exists(file_to_check))128 return false;129 }130 131 return true;132}133 134CppModuleConfiguration::CppModuleConfiguration(135 const FileSpecList &support_files, const llvm::Triple &triple) {136 // Analyze all files we were given to build the configuration.137 bool error = !llvm::all_of(support_files, [&](auto &file) {138 return CppModuleConfiguration::analyzeFile(file, triple);139 });140 // If we have a valid configuration at this point, set the141 // include directories and module list that should be used.142 if (!error && hasValidConfig()) {143 // Calculate the resource directory for LLDB.144 llvm::SmallString<256> resource_dir;145 llvm::sys::path::append(resource_dir, GetClangResourceDir().GetPath(),146 "include");147 m_resource_inc = std::string(resource_dir.str());148 149 // This order matches the way Clang orders these directories.150 m_include_dirs = {m_std_inc.Get().str(), m_resource_inc,151 m_c_inc.Get().str()};152 if (m_c_target_inc.Valid())153 m_include_dirs.push_back(m_c_target_inc.Get().str());154 if (m_std_target_inc.Valid())155 m_include_dirs.push_back(m_std_target_inc.Get().str());156 m_imported_modules = {"std"};157 }158}159