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-exception 6 // 7 //===----------------------------------------------------------------------===// 8 9 #include "CppModuleConfiguration.h" 10 11 #include "ClangHost.h" 12 #include "lldb/Host/FileSystem.h" 13 14 using namespace lldb_private; 15 16 bool CppModuleConfiguration::SetOncePath::TrySet(llvm::StringRef path) { 17 // Setting for the first time always works. 18 if (m_first) { 19 m_path = path.str(); 20 m_valid = true; 21 m_first = false; 22 return true; 23 } 24 // Changing the path to the same value is fine. 25 if (m_path == path) 26 return true; 27 28 // Changing the path after it was already set is not allowed. 29 m_valid = false; 30 return false; 31 } 32 33 bool CppModuleConfiguration::analyzeFile(const FileSpec &f) { 34 using namespace llvm::sys::path; 35 // Convert to slashes to make following operations simpler. 36 std::string dir_buffer = convert_to_slash(f.GetDirectory().GetStringRef()); 37 llvm::StringRef posix_dir(dir_buffer); 38 39 // Check for /c++/vX/ that is used by libc++. 40 static llvm::Regex libcpp_regex(R"regex(/c[+][+]/v[0-9]/)regex"); 41 // If the path is in the libc++ include directory use it as the found libc++ 42 // path. Ignore subdirectories such as /c++/v1/experimental as those don't 43 // need to be specified in the header search. 44 if (libcpp_regex.match(f.GetPath()) && 45 parent_path(posix_dir, Style::posix).endswith("c++")) { 46 return m_std_inc.TrySet(posix_dir); 47 } 48 49 // Check for /usr/include. On Linux this might be /usr/include/bits, so 50 // we should remove that '/bits' suffix to get the actual include directory. 51 if (posix_dir.endswith("/usr/include/bits")) 52 posix_dir.consume_back("/bits"); 53 if (posix_dir.endswith("/usr/include")) 54 return m_c_inc.TrySet(posix_dir); 55 56 // File wasn't interesting, continue analyzing. 57 return true; 58 } 59 60 /// Utility function for just appending two paths. 61 static std::string MakePath(llvm::StringRef lhs, llvm::StringRef rhs) { 62 llvm::SmallString<256> result(lhs); 63 llvm::sys::path::append(result, rhs); 64 return std::string(result); 65 } 66 67 bool CppModuleConfiguration::hasValidConfig() { 68 // We need to have a C and C++ include dir for a valid configuration. 69 if (!m_c_inc.Valid() || !m_std_inc.Valid()) 70 return false; 71 72 // Do some basic sanity checks on the directories that we don't activate 73 // the module when it's clear that it's not usable. 74 const std::vector<std::string> files_to_check = { 75 // * Check that the C library contains at least one random C standard 76 // library header. 77 MakePath(m_c_inc.Get(), "stdio.h"), 78 // * Without a libc++ modulemap file we can't have a 'std' module that 79 // could be imported. 80 MakePath(m_std_inc.Get(), "module.modulemap"), 81 // * Check for a random libc++ header (vector in this case) that has to 82 // exist in a working libc++ setup. 83 MakePath(m_std_inc.Get(), "vector"), 84 }; 85 86 for (llvm::StringRef file_to_check : files_to_check) { 87 if (!FileSystem::Instance().Exists(file_to_check)) 88 return false; 89 } 90 91 return true; 92 } 93 94 CppModuleConfiguration::CppModuleConfiguration( 95 const FileSpecList &support_files) { 96 // Analyze all files we were given to build the configuration. 97 bool error = !llvm::all_of(support_files, 98 std::bind(&CppModuleConfiguration::analyzeFile, 99 this, std::placeholders::_1)); 100 // If we have a valid configuration at this point, set the 101 // include directories and module list that should be used. 102 if (!error && hasValidConfig()) { 103 // Calculate the resource directory for LLDB. 104 llvm::SmallString<256> resource_dir; 105 llvm::sys::path::append(resource_dir, GetClangResourceDir().GetPath(), 106 "include"); 107 m_resource_inc = std::string(resource_dir.str()); 108 109 // This order matches the way Clang orders these directories. 110 m_include_dirs = {m_std_inc.Get().str(), m_resource_inc, 111 m_c_inc.Get().str()}; 112 m_imported_modules = {"std"}; 113 } 114 } 115