1 //===- lib/Linker/Linker.cpp - Basic Linker functionality ----------------===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file contains basic Linker functionality that all usages will need. 11 // 12 //===----------------------------------------------------------------------===// 13 14 #include "llvm/Linker.h" 15 #include "llvm/Module.h" 16 #include "llvm/Bitcode/ReaderWriter.h" 17 #include "llvm/Support/Path.h" 18 #include "llvm/Support/MemoryBuffer.h" 19 #include "llvm/Support/raw_ostream.h" 20 #include "llvm/Config/config.h" 21 #include "llvm/Support/system_error.h" 22 using namespace llvm; 23 24 Linker::Linker(StringRef progname, StringRef modname, 25 LLVMContext& C, unsigned flags): 26 Context(C), 27 Composite(new Module(modname, C)), 28 LibPaths(), 29 Flags(flags), 30 Error(), 31 ProgramName(progname) { } 32 33 Linker::Linker(StringRef progname, Module* aModule, unsigned flags) : 34 Context(aModule->getContext()), 35 Composite(aModule), 36 LibPaths(), 37 Flags(flags), 38 Error(), 39 ProgramName(progname) { } 40 41 Linker::~Linker() { 42 delete Composite; 43 } 44 45 bool 46 Linker::error(StringRef message) { 47 Error = message; 48 if (!(Flags&QuietErrors)) 49 errs() << ProgramName << ": error: " << message << "\n"; 50 return true; 51 } 52 53 bool 54 Linker::warning(StringRef message) { 55 Error = message; 56 if (!(Flags&QuietWarnings)) 57 errs() << ProgramName << ": warning: " << message << "\n"; 58 return false; 59 } 60 61 void 62 Linker::verbose(StringRef message) { 63 if (Flags&Verbose) 64 errs() << " " << message << "\n"; 65 } 66 67 void 68 Linker::addPath(const sys::Path& path) { 69 LibPaths.push_back(path); 70 } 71 72 void 73 Linker::addPaths(const std::vector<std::string>& paths) { 74 for (unsigned i = 0, e = paths.size(); i != e; ++i) 75 LibPaths.push_back(sys::Path(paths[i])); 76 } 77 78 void 79 Linker::addSystemPaths() { 80 sys::Path::GetBitcodeLibraryPaths(LibPaths); 81 LibPaths.insert(LibPaths.begin(),sys::Path("./")); 82 } 83 84 Module* 85 Linker::releaseModule() { 86 Module* result = Composite; 87 LibPaths.clear(); 88 Error.clear(); 89 Composite = 0; 90 Flags = 0; 91 return result; 92 } 93 94 // LoadObject - Read in and parse the bitcode file named by FN and return the 95 // module it contains (wrapped in an auto_ptr), or auto_ptr<Module>() and set 96 // Error if an error occurs. 97 std::auto_ptr<Module> 98 Linker::LoadObject(const sys::Path &FN) { 99 std::string ParseErrorMessage; 100 Module *Result = 0; 101 102 OwningPtr<MemoryBuffer> Buffer; 103 if (error_code ec = MemoryBuffer::getFileOrSTDIN(FN.c_str(), Buffer)) 104 ParseErrorMessage = "Error reading file '" + FN.str() + "'" + ": " 105 + ec.message(); 106 else 107 Result = ParseBitcodeFile(Buffer.get(), Context, &ParseErrorMessage); 108 109 if (Result) 110 return std::auto_ptr<Module>(Result); 111 Error = "Bitcode file '" + FN.str() + "' could not be loaded"; 112 if (ParseErrorMessage.size()) 113 Error += ": " + ParseErrorMessage; 114 return std::auto_ptr<Module>(); 115 } 116 117 // IsLibrary - Determine if "Name" is a library in "Directory". Return 118 // a non-empty sys::Path if its found, an empty one otherwise. 119 static inline sys::Path IsLibrary(StringRef Name, 120 const sys::Path &Directory) { 121 122 sys::Path FullPath(Directory); 123 124 // Try the libX.a form 125 FullPath.appendComponent(("lib" + Name).str()); 126 FullPath.appendSuffix("a"); 127 if (FullPath.isArchive()) 128 return FullPath; 129 130 // Try the libX.bca form 131 FullPath.eraseSuffix(); 132 FullPath.appendSuffix("bca"); 133 if (FullPath.isArchive()) 134 return FullPath; 135 136 // Try the libX.so (or .dylib) form 137 FullPath.eraseSuffix(); 138 FullPath.appendSuffix(sys::Path::GetDLLSuffix()); 139 if (FullPath.isDynamicLibrary()) // Native shared library? 140 return FullPath; 141 if (FullPath.isBitcodeFile()) // .so file containing bitcode? 142 return FullPath; 143 144 // Try libX form, to make it possible to add dependency on the 145 // specific version of .so, like liblzma.so.1.0.0 146 FullPath.eraseSuffix(); 147 if (FullPath.isDynamicLibrary()) // Native shared library? 148 return FullPath; 149 if (FullPath.isBitcodeFile()) // .so file containing bitcode? 150 return FullPath; 151 152 // Not found .. fall through 153 154 // Indicate that the library was not found in the directory. 155 FullPath.clear(); 156 return FullPath; 157 } 158 159 /// FindLib - Try to convert Filename into the name of a file that we can open, 160 /// if it does not already name a file we can open, by first trying to open 161 /// Filename, then libFilename.[suffix] for each of a set of several common 162 /// library suffixes, in each of the directories in LibPaths. Returns an empty 163 /// Path if no matching file can be found. 164 /// 165 sys::Path 166 Linker::FindLib(StringRef Filename) { 167 // Determine if the pathname can be found as it stands. 168 sys::Path FilePath(Filename); 169 if (FilePath.canRead() && 170 (FilePath.isArchive() || FilePath.isDynamicLibrary())) 171 return FilePath; 172 173 // Iterate over the directories in Paths to see if we can find the library 174 // there. 175 for (unsigned Index = 0; Index != LibPaths.size(); ++Index) { 176 sys::Path Directory(LibPaths[Index]); 177 sys::Path FullPath = IsLibrary(Filename, Directory); 178 if (!FullPath.isEmpty()) 179 return FullPath; 180 } 181 return sys::Path(); 182 } 183