1 //===-- ClangHost.cpp -------------------------------------------*- C++ -*-===// 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 "ClangHost.h" 10 11 #include "clang/Basic/Version.h" 12 #include "clang/Config/config.h" 13 14 #include "llvm/ADT/StringRef.h" 15 #include "llvm/ADT/Twine.h" 16 #include "llvm/Support/FileSystem.h" 17 #include "llvm/Support/Threading.h" 18 19 #include "lldb/Host/Config.h" 20 #include "lldb/Host/FileSystem.h" 21 #include "lldb/Host/HostInfo.h" 22 #include "lldb/Utility/FileSpec.h" 23 #include "lldb/Utility/Log.h" 24 25 #include <string> 26 27 using namespace lldb_private; 28 29 static bool VerifyClangPath(const llvm::Twine &clang_path) { 30 if (FileSystem::Instance().IsDirectory(clang_path)) 31 return true; 32 Log *log = lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_HOST); 33 if (log) 34 log->Printf("VerifyClangPath(): " 35 "failed to stat clang resource directory at \"%s\"", 36 clang_path.str().c_str()); 37 return false; 38 } 39 40 /// 41 /// This will compute the clang resource directory assuming that clang was 42 /// installed with the same prefix as lldb. 43 /// 44 /// If verify is true, the first candidate resource directory will be returned. 45 /// This mode is only used for testing. 46 /// 47 static bool DefaultComputeClangResourceDirectory(FileSpec &lldb_shlib_spec, 48 FileSpec &file_spec, 49 bool verify) { 50 Log *log = lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_HOST); 51 std::string raw_path = lldb_shlib_spec.GetPath(); 52 llvm::StringRef parent_dir = llvm::sys::path::parent_path(raw_path); 53 54 static const llvm::StringRef kResourceDirSuffixes[] = { 55 // LLVM.org's build of LLDB uses the clang resource directory placed 56 // in $install_dir/lib{,64}/clang/$clang_version. 57 "lib" CLANG_LIBDIR_SUFFIX "/clang/" CLANG_VERSION_STRING, 58 // swift-lldb uses the clang resource directory copied from swift, which 59 // by default is placed in $install_dir/lib{,64}/lldb/clang. LLDB places 60 // it there, so we use LLDB_LIBDIR_SUFFIX. 61 "lib" LLDB_LIBDIR_SUFFIX "/lldb/clang", 62 }; 63 64 for (const auto &Suffix : kResourceDirSuffixes) { 65 llvm::SmallString<256> clang_dir(parent_dir); 66 llvm::SmallString<32> relative_path(Suffix); 67 llvm::sys::path::native(relative_path); 68 llvm::sys::path::append(clang_dir, relative_path); 69 if (!verify || VerifyClangPath(clang_dir)) { 70 if (log) 71 log->Printf("DefaultComputeClangResourceDir: Setting ClangResourceDir " 72 "to \"%s\", verify = %s", 73 clang_dir.str().str().c_str(), verify ? "true" : "false"); 74 file_spec.GetDirectory().SetString(clang_dir); 75 FileSystem::Instance().Resolve(file_spec); 76 return true; 77 } 78 } 79 80 return false; 81 } 82 83 bool lldb_private::ComputeClangResourceDirectory(FileSpec &lldb_shlib_spec, 84 FileSpec &file_spec, bool verify) { 85 #if !defined(__APPLE__) 86 return DefaultComputeClangResourceDirectory(lldb_shlib_spec, file_spec, 87 verify); 88 #else 89 std::string raw_path = lldb_shlib_spec.GetPath(); 90 91 auto rev_it = llvm::sys::path::rbegin(raw_path); 92 auto r_end = llvm::sys::path::rend(raw_path); 93 94 // Check for a Posix-style build of LLDB. 95 while (rev_it != r_end) { 96 if (*rev_it == "LLDB.framework") 97 break; 98 ++rev_it; 99 } 100 101 // We found a non-framework build of LLDB 102 if (rev_it == r_end) 103 return DefaultComputeClangResourceDirectory(lldb_shlib_spec, file_spec, 104 verify); 105 106 // Inside Xcode and in Xcode toolchains LLDB is always in lockstep 107 // with the Swift compiler, so it can reuse its Clang resource 108 // directory. This allows LLDB and the Swift compiler to share the 109 // same Clang module cache. 110 llvm::SmallString<256> clang_path; 111 const char *swift_clang_resource_dir = "usr/lib/swift/clang"; 112 auto parent = std::next(rev_it); 113 if (parent != r_end && *parent == "SharedFrameworks") { 114 // This is the top-level LLDB in the Xcode.app bundle. 115 // E.g., "Xcode.app/Contents/SharedFrameworks/LLDB.framework/Versions/A" 116 raw_path.resize(parent - r_end); 117 llvm::sys::path::append(clang_path, raw_path, 118 "Developer/Toolchains/XcodeDefault.xctoolchain", 119 swift_clang_resource_dir); 120 if (!verify || VerifyClangPath(clang_path)) { 121 file_spec.GetDirectory().SetString(clang_path.c_str()); 122 FileSystem::Instance().Resolve(file_spec); 123 return true; 124 } 125 } else if (parent != r_end && *parent == "PrivateFrameworks" && 126 std::distance(parent, r_end) > 2) { 127 ++parent; 128 ++parent; 129 if (*parent == "System") { 130 // This is LLDB inside an Xcode toolchain. 131 // E.g., "Xcode.app/Contents/Developer/Toolchains/" \ 132 // "My.xctoolchain/System/Library/PrivateFrameworks/LLDB.framework" 133 raw_path.resize(parent - r_end); 134 llvm::sys::path::append(clang_path, raw_path, swift_clang_resource_dir); 135 if (!verify || VerifyClangPath(clang_path)) { 136 file_spec.GetDirectory().SetString(clang_path.c_str()); 137 FileSystem::Instance().Resolve(file_spec); 138 return true; 139 } 140 raw_path = lldb_shlib_spec.GetPath(); 141 } 142 raw_path.resize(rev_it - r_end); 143 } else { 144 raw_path.resize(rev_it - r_end); 145 } 146 147 // Fall back to the Clang resource directory inside the framework. 148 raw_path.append("LLDB.framework/Resources/Clang"); 149 file_spec.GetDirectory().SetString(raw_path.c_str()); 150 FileSystem::Instance().Resolve(file_spec); 151 return true; 152 #endif // __APPLE__ 153 } 154 155 FileSpec lldb_private::GetClangResourceDir() { 156 static FileSpec g_cached_resource_dir; 157 static llvm::once_flag g_once_flag; 158 llvm::call_once(g_once_flag, []() { 159 if (FileSpec lldb_file_spec = HostInfo::GetShlibDir()) 160 ComputeClangResourceDirectory(lldb_file_spec, g_cached_resource_dir, 161 true); 162 Log *log = lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_HOST); 163 if (log) 164 log->Printf("GetClangResourceDir() => '%s'", 165 g_cached_resource_dir.GetPath().c_str()); 166 }); 167 return g_cached_resource_dir; 168 } 169