1 //===- ELFDynObjReader.cpp ------------------------------------------------===// 2 // 3 // The MCLinker Project 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 #include "mcld/LD/ELFDynObjReader.h" 10 11 #include "mcld/IRBuilder.h" 12 #include "mcld/LinkerConfig.h" 13 #include "mcld/LD/ELFReader.h" 14 #include "mcld/LD/LDContext.h" 15 #include "mcld/MC/Input.h" 16 #include "mcld/Support/MemoryArea.h" 17 #include "mcld/Target/GNULDBackend.h" 18 19 #include <llvm/ADT/StringRef.h> 20 #include <llvm/ADT/Twine.h> 21 #include <llvm/Support/ErrorHandling.h> 22 23 #include <string> 24 25 namespace mcld { 26 27 //===----------------------------------------------------------------------===// 28 // ELFDynObjReader 29 //===----------------------------------------------------------------------===// 30 ELFDynObjReader::ELFDynObjReader(GNULDBackend& pBackend, 31 IRBuilder& pBuilder, 32 const LinkerConfig& pConfig) 33 : DynObjReader(), m_pELFReader(0), m_Builder(pBuilder) { 34 if (pConfig.targets().is32Bits() && pConfig.targets().isLittleEndian()) 35 m_pELFReader = new ELFReader<32, true>(pBackend); 36 else if (pConfig.targets().is64Bits() && pConfig.targets().isLittleEndian()) 37 m_pELFReader = new ELFReader<64, true>(pBackend); 38 } 39 40 ELFDynObjReader::~ELFDynObjReader() { 41 delete m_pELFReader; 42 } 43 44 /// isMyFormat 45 bool ELFDynObjReader::isMyFormat(Input& pInput, bool& pContinue) const { 46 assert(pInput.hasMemArea()); 47 48 // Don't warning about the frequently requests. 49 // MemoryArea has a list of cache to handle this. 50 size_t hdr_size = m_pELFReader->getELFHeaderSize(); 51 if (pInput.memArea()->size() < hdr_size) 52 return false; 53 54 llvm::StringRef region = 55 pInput.memArea()->request(pInput.fileOffset(), hdr_size); 56 57 const char* ELF_hdr = region.begin(); 58 bool result = true; 59 if (!m_pELFReader->isELF(ELF_hdr)) { 60 pContinue = true; 61 result = false; 62 } else if (Input::DynObj != m_pELFReader->fileType(ELF_hdr)) { 63 pContinue = true; 64 result = false; 65 } else if (!m_pELFReader->isMyEndian(ELF_hdr)) { 66 pContinue = false; 67 result = false; 68 } else if (!m_pELFReader->isMyMachine(ELF_hdr)) { 69 pContinue = false; 70 result = false; 71 } 72 return result; 73 } 74 75 /// readHeader 76 bool ELFDynObjReader::readHeader(Input& pInput) { 77 assert(pInput.hasMemArea()); 78 79 size_t hdr_size = m_pELFReader->getELFHeaderSize(); 80 llvm::StringRef region = 81 pInput.memArea()->request(pInput.fileOffset(), hdr_size); 82 const char* ELF_hdr = region.begin(); 83 84 bool shdr_result = m_pELFReader->readSectionHeaders(pInput, ELF_hdr); 85 86 // read .dynamic to get the correct SONAME 87 bool dyn_result = m_pELFReader->readDynamic(pInput); 88 89 return (shdr_result && dyn_result); 90 } 91 92 /// readSymbols 93 bool ELFDynObjReader::readSymbols(Input& pInput) { 94 assert(pInput.hasMemArea()); 95 96 LDSection* symtab_shdr = pInput.context()->getSection(".dynsym"); 97 if (symtab_shdr == NULL) { 98 note(diag::note_has_no_symtab) << pInput.name() << pInput.path() 99 << ".dynsym"; 100 return true; 101 } 102 103 LDSection* strtab_shdr = symtab_shdr->getLink(); 104 if (strtab_shdr == NULL) { 105 fatal(diag::fatal_cannot_read_strtab) << pInput.name() << pInput.path() 106 << ".dynsym"; 107 return false; 108 } 109 110 llvm::StringRef symtab_region = pInput.memArea()->request( 111 pInput.fileOffset() + symtab_shdr->offset(), symtab_shdr->size()); 112 113 llvm::StringRef strtab_region = pInput.memArea()->request( 114 pInput.fileOffset() + strtab_shdr->offset(), strtab_shdr->size()); 115 const char* strtab = strtab_region.begin(); 116 bool result = 117 m_pELFReader->readSymbols(pInput, m_Builder, symtab_region, strtab); 118 return result; 119 } 120 121 } // namespace mcld 122
