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