lib/Linker/Linker.cpp

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