lib/Archive/Archive.cpp

   1 //===-- Archive.cpp - Generic LLVM archive functions ------------*- C++ -*-===//
   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 the implementation of the Archive and ArchiveMember
  11 // classes that is common to both reading and writing archives..
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #include "ArchiveInternals.h"
  16 #include "llvm/Bitcode/ReaderWriter.h"
  17 #include "llvm/ModuleProvider.h"
  18 #include "llvm/Module.h"
  19 #include "llvm/Support/MemoryBuffer.h"
  20 #include "llvm/System/Process.h"
  21 using namespace llvm;
  22
  23 // getMemberSize - compute the actual physical size of the file member as seen
  24 // on disk. This isn't the size of member's payload. Use getSize() for that.
  25 unsigned
  26 ArchiveMember::getMemberSize() const {
  27   // Basically its the file size plus the header size
  28   unsigned result =  info.fileSize + sizeof(ArchiveMemberHeader);
  29
  30   // If it has a long filename, include the name length
  31   if (hasLongFilename())
  32     result += path.toString().length() + 1;
  33
  34   // If its now odd lengthed, include the padding byte
  35   if (result % 2 != 0 )
  36     result++;
  37
  38   return result;
  39 }
  40
  41 // This default constructor is only use by the ilist when it creates its
  42 // sentry node. We give it specific static values to make it stand out a bit.
  43 ArchiveMember::ArchiveMember()
  44   : next(0), prev(0), parent(0), path("--invalid--"), flags(0), data(0)
  45 {
  46   info.user = sys::Process::GetCurrentUserId();
  47   info.group = sys::Process::GetCurrentGroupId();
  48   info.mode = 0777;
  49   info.fileSize = 0;
  50   info.modTime = sys::TimeValue::now();
  51 }
  52
  53 // This is the constructor that the Archive class uses when it is building or
  54 // reading an archive. It just defaults a few things and ensures the parent is
  55 // set for the iplist. The Archive class fills in the ArchiveMember's data.
  56 // This is required because correctly setting the data may depend on other
  57 // things in the Archive.
  58 ArchiveMember::ArchiveMember(Archive* PAR)
  59   : next(0), prev(0), parent(PAR), path(), flags(0), data(0)
  60 {
  61 }
  62
  63 // This method allows an ArchiveMember to be replaced with the data for a
  64 // different file, presumably as an update to the member. It also makes sure
  65 // the flags are reset correctly.
  66 bool ArchiveMember::replaceWith(const sys::Path& newFile, std::string* ErrMsg) {
  67   if (!newFile.exists()) {
  68     if (ErrMsg)
  69       *ErrMsg = "Can not replace an archive member with a non-existent file";
  70     return true;
  71   }
  72
  73   data = 0;
  74   path = newFile;
  75
  76   // SVR4 symbol tables have an empty name
  77   if (path.toString() == ARFILE_SVR4_SYMTAB_NAME)
  78     flags |= SVR4SymbolTableFlag;
  79   else
  80     flags &= ~SVR4SymbolTableFlag;
  81
  82   // BSD4.4 symbol tables have a special name
  83   if (path.toString() == ARFILE_BSD4_SYMTAB_NAME)
  84     flags |= BSD4SymbolTableFlag;
  85   else
  86     flags &= ~BSD4SymbolTableFlag;
  87
  88   // LLVM symbol tables have a very specific name
  89   if (path.toString() == ARFILE_LLVM_SYMTAB_NAME)
  90     flags |= LLVMSymbolTableFlag;
  91   else
  92     flags &= ~LLVMSymbolTableFlag;
  93
  94   // String table name
  95   if (path.toString() == ARFILE_STRTAB_NAME)
  96     flags |= StringTableFlag;
  97   else
  98     flags &= ~StringTableFlag;
  99
 100   // If it has a slash then it has a path
 101   bool hasSlash = path.toString().find('/') != std::string::npos;
 102   if (hasSlash)
 103     flags |= HasPathFlag;
 104   else
 105     flags &= ~HasPathFlag;
 106
 107   // If it has a slash or its over 15 chars then its a long filename format
 108   if (hasSlash || path.toString().length() > 15)
 109     flags |= HasLongFilenameFlag;
 110   else
 111     flags &= ~HasLongFilenameFlag;
 112
 113   // Get the signature and status info
 114   const char* signature = (const char*) data;
 115   std::string magic;
 116   if (!signature) {
 117     path.getMagicNumber(magic,4);
 118     signature = magic.c_str();
 119     std::string err;
 120     const sys::FileStatus *FSinfo = path.getFileStatus(false, ErrMsg);
 121     if (FSinfo)
 122       info = *FSinfo;
 123     else
 124       return true;
 125   }
 126
 127   // Determine what kind of file it is
 128   switch (sys::IdentifyFileType(signature,4)) {
 129     default:
 130       flags &= ~BitcodeFlag;
 131       break;
 132   }
 133   return false;
 134 }
 135
 136 // Archive constructor - this is the only constructor that gets used for the
 137 // Archive class. Everything else (default,copy) is deprecated. This just
 138 // initializes and maps the file into memory, if requested.
 139 Archive::Archive(const sys::Path& filename)
 140   : archPath(filename), members(), mapfile(0), base(0), symTab(), strtab(),
 141     symTabSize(0), firstFileOffset(0), modules(), foreignST(0) {
 142 }
 143
 144 bool
 145 Archive::mapToMemory(std::string* ErrMsg)
 146 {
 147   mapfile = new sys::MappedFile();
 148   if (mapfile->open(archPath, sys::MappedFile::READ_ACCESS, ErrMsg))
 149     return true;
 150   if (!(base = (char*) mapfile->map(ErrMsg)))
 151     return true;
 152   return false;
 153 }
 154
 155 void Archive::cleanUpMemory() {
 156   // Shutdown the file mapping
 157   if (mapfile) {
 158     mapfile->close();
 159     delete mapfile;
 160
 161     mapfile = 0;
 162     base = 0;
 163   }
 164
 165   // Forget the entire symbol table
 166   symTab.clear();
 167   symTabSize = 0;
 168
 169   firstFileOffset = 0;
 170
 171   // Free the foreign symbol table member
 172   if (foreignST) {
 173     delete foreignST;
 174     foreignST = 0;
 175   }
 176
 177   // Delete any ModuleProviders and ArchiveMember's we've allocated as a result
 178   // of symbol table searches.
 179   for (ModuleMap::iterator I=modules.begin(), E=modules.end(); I != E; ++I ) {
 180     delete I->second.first;
 181     delete I->second.second;
 182   }
 183 }
 184
 185 // Archive destructor - just clean up memory
 186 Archive::~Archive() {
 187   cleanUpMemory();
 188 }
 189
 190
 191
 192 static void getSymbols(Module*M, std::vector<std::string>& symbols) {
 193   // Loop over global variables
 194   for (Module::global_iterator GI = M->global_begin(), GE=M->global_end(); GI != GE; ++GI)
 195     if (!GI->isDeclaration() && !GI->hasInternalLinkage())
 196       if (!GI->getName().empty())
 197         symbols.push_back(GI->getName());
 198
 199   // Loop over functions.
 200   for (Module::iterator FI = M->begin(), FE = M->end(); FI != FE; ++FI)
 201     if (!FI->isDeclaration() && !FI->hasInternalLinkage())
 202       if (!FI->getName().empty())
 203         symbols.push_back(FI->getName());
 204 }
 205
 206 // Get just the externally visible defined symbols from the bitcode
 207 bool llvm::GetBitcodeSymbols(const sys::Path& fName,
 208                              std::vector<std::string>& symbols,
 209                              std::string* ErrMsg) {
 210   std::auto_ptr<MemoryBuffer> Buffer(
 211                        MemoryBuffer::getFileOrSTDIN(&fName.toString()[0],
 212                                                     fName.toString().size()));
 213   if (!Buffer.get()) {
 214     if (ErrMsg) *ErrMsg = "Could not open file '" + fName.toString() + "'";
 215     return true;
 216   }
 217
 218   ModuleProvider *MP = getBitcodeModuleProvider(Buffer.get(), ErrMsg);
 219   if (!MP)
 220     return true;
 221
 222   // Get the module from the provider
 223   Module* M = MP->materializeModule();
 224   if (M == 0) {
 225     delete MP;
 226     return true;
 227   }
 228
 229   // Get the symbols
 230   getSymbols(M, symbols);
 231
 232   // Done with the module.
 233   delete MP;
 234   return true;
 235 }
 236
 237 ModuleProvider*
 238 llvm::GetBitcodeSymbols(const unsigned char *BufPtr, unsigned Length,
 239                         const std::string& ModuleID,
 240                         std::vector<std::string>& symbols,
 241                         std::string* ErrMsg) {
 242   // Get the module provider
 243   MemoryBuffer *Buffer =MemoryBuffer::getNewMemBuffer(Length, ModuleID.c_str());
 244   memcpy((char*)Buffer->getBufferStart(), BufPtr, Length);
 245
 246   ModuleProvider *MP = getBitcodeModuleProvider(Buffer, ErrMsg);
 247   if (!MP)
 248     return 0;
 249
 250   // Get the module from the provider
 251   Module* M = MP->materializeModule();
 252   if (M == 0) {
 253     delete MP;
 254     return 0;
 255   }
 256
 257   // Get the symbols
 258   getSymbols(M, symbols);
 259
 260   // Done with the module. Note that ModuleProvider will delete the
 261   // Module when it is deleted. Also note that its the caller's responsibility
 262   // to delete the ModuleProvider.
 263   return MP;
 264 }