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/LinkerConfig.h>
12 #include <mcld/IRBuilder.h>
13 #include <mcld/LD/ELFReader.h>
14 #include <mcld/MC/MCLDInput.h>
15 #include <mcld/Support/MemoryRegion.h>
16 #include <mcld/Target/GNULDBackend.h>
17
18 #include <llvm/ADT/Twine.h>
19 #include <llvm/ADT/OwningPtr.h>
20 #include <llvm/Support/ErrorHandling.h>
21
22 #include <string>
23
24 using namespace mcld;
25
26 //===----------------------------------------------------------------------===//
27 // ELFDynObjReader
28 //===----------------------------------------------------------------------===//
ELFDynObjReader(GNULDBackend & pBackend,IRBuilder & pBuilder,const LinkerConfig & pConfig)29 ELFDynObjReader::ELFDynObjReader(GNULDBackend& pBackend,
30 IRBuilder& pBuilder,
31 const LinkerConfig& pConfig)
32 : DynObjReader(),
33 m_pELFReader(0),
34 m_Builder(pBuilder) {
35 if (pConfig.targets().is32Bits() && pConfig.targets().isLittleEndian())
36 m_pELFReader = new ELFReader<32, true>(pBackend);
37 else if (pConfig.targets().is64Bits() && pConfig.targets().isLittleEndian())
38 m_pELFReader = new ELFReader<64, true>(pBackend);
39 }
40
~ELFDynObjReader()41 ELFDynObjReader::~ELFDynObjReader()
42 {
43 delete m_pELFReader;
44 }
45
46 /// isMyFormat
isMyFormat(Input & pInput) const47 bool ELFDynObjReader::isMyFormat(Input &pInput) const
48 {
49 assert(pInput.hasMemArea());
50
51 // Don't warning about the frequently requests.
52 // MemoryArea has a list of cache to handle this.
53 size_t hdr_size = m_pELFReader->getELFHeaderSize();
54 MemoryRegion* region = pInput.memArea()->request(pInput.fileOffset(),
55 hdr_size);
56
57 uint8_t* ELF_hdr = region->start();
58 bool result = true;
59 if (!m_pELFReader->isELF(ELF_hdr))
60 result = false;
61 else if (!m_pELFReader->isMyEndian(ELF_hdr))
62 result = false;
63 else if (!m_pELFReader->isMyMachine(ELF_hdr))
64 result = false;
65 else if (Input::DynObj != m_pELFReader->fileType(ELF_hdr))
66 result = false;
67 pInput.memArea()->release(region);
68 return result;
69 }
70
71 /// readHeader
readHeader(Input & pInput)72 bool ELFDynObjReader::readHeader(Input& pInput)
73 {
74 assert(pInput.hasMemArea());
75
76 size_t hdr_size = m_pELFReader->getELFHeaderSize();
77 MemoryRegion* region = pInput.memArea()->request(pInput.fileOffset(),
78 hdr_size);
79 uint8_t* ELF_hdr = region->start();
80
81 bool shdr_result = m_pELFReader->readSectionHeaders(pInput, ELF_hdr);
82 pInput.memArea()->release(region);
83
84 // read .dynamic to get the correct SONAME
85 bool dyn_result = m_pELFReader->readDynamic(pInput);
86
87 return (shdr_result && dyn_result);
88 }
89
90 /// readSymbols
readSymbols(Input & pInput)91 bool ELFDynObjReader::readSymbols(Input& pInput)
92 {
93 assert(pInput.hasMemArea());
94
95 LDSection* symtab_shdr = pInput.context()->getSection(".dynsym");
96 if (NULL == symtab_shdr) {
97 note(diag::note_has_no_symtab) << pInput.name()
98 << pInput.path()
99 << ".dynsym";
100 return true;
101 }
102
103 LDSection* strtab_shdr = symtab_shdr->getLink();
104 if (NULL == strtab_shdr) {
105 fatal(diag::fatal_cannot_read_strtab) << pInput.name()
106 << pInput.path()
107 << ".dynsym";
108 return false;
109 }
110
111 MemoryRegion* symtab_region = pInput.memArea()->request(
112 pInput.fileOffset() + symtab_shdr->offset(), symtab_shdr->size());
113
114 MemoryRegion* strtab_region = pInput.memArea()->request(
115 pInput.fileOffset() + strtab_shdr->offset(), strtab_shdr->size());
116 char* strtab = reinterpret_cast<char*>(strtab_region->start());
117 bool result = m_pELFReader->readSymbols(pInput, m_Builder,
118 *symtab_region, strtab);
119 pInput.memArea()->release(symtab_region);
120 pInput.memArea()->release(strtab_region);
121
122 return result;
123 }
124
125