1 //===- COFFObjectFile.cpp - COFF object file implementation -----*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file declares the COFFObjectFile class.
12 //===----------------------------------------------------------------------===//
14 #include "llvm/ADT/StringSwitch.h"
15 #include "llvm/ADT/Triple.h"
16 #include "llvm/Object/ObjectFile.h"
17 #include "llvm/Support/COFF.h"
18 #include "llvm/Support/Endian.h"
21 using namespace object;
24 using support::ulittle8_t;
25 using support::ulittle16_t;
26 using support::ulittle32_t;
27 using support::little16_t;
31 struct coff_file_header {
33 ulittle16_t NumberOfSections;
34 ulittle32_t TimeDateStamp;
35 ulittle32_t PointerToSymbolTable;
36 ulittle32_t NumberOfSymbols;
37 ulittle16_t SizeOfOptionalHeader;
38 ulittle16_t Characteristics;
42 extern char coff_file_header_layout_static_assert
43 [sizeof(coff_file_header) == 20 ? 1 : -1];
47 struct StringTableOffset {
54 StringTableOffset Offset;
58 little16_t SectionNumber;
62 ulittle8_t ComplexType;
65 ulittle8_t StorageClass;
66 ulittle8_t NumberOfAuxSymbols;
70 extern char coff_coff_symbol_layout_static_assert
71 [sizeof(coff_symbol) == 18 ? 1 : -1];
76 ulittle32_t VirtualSize;
77 ulittle32_t VirtualAddress;
78 ulittle32_t SizeOfRawData;
79 ulittle32_t PointerToRawData;
80 ulittle32_t PointerToRelocations;
81 ulittle32_t PointerToLinenumbers;
82 ulittle16_t NumberOfRelocations;
83 ulittle16_t NumberOfLinenumbers;
84 ulittle32_t Characteristics;
88 extern char coff_coff_section_layout_static_assert
89 [sizeof(coff_section) == 40 ? 1 : -1];
92 class COFFObjectFile : public ObjectFile {
94 const coff_file_header *Header;
95 const coff_section *SectionTable;
96 const coff_symbol *SymbolTable;
97 const char *StringTable;
99 const coff_section *getSection(std::size_t index) const;
100 const char *getString(std::size_t offset) const;
103 virtual SymbolRef getSymbolNext(DataRefImpl Symb) const;
104 virtual StringRef getSymbolName(DataRefImpl Symb) const;
105 virtual uint64_t getSymbolAddress(DataRefImpl Symb) const;
106 virtual uint64_t getSymbolSize(DataRefImpl Symb) const;
107 virtual char getSymbolNMTypeChar(DataRefImpl Symb) const;
108 virtual bool isSymbolInternal(DataRefImpl Symb) const;
110 virtual SectionRef getSectionNext(DataRefImpl Sec) const;
111 virtual StringRef getSectionName(DataRefImpl Sec) const;
112 virtual uint64_t getSectionAddress(DataRefImpl Sec) const;
113 virtual uint64_t getSectionSize(DataRefImpl Sec) const;
114 virtual StringRef getSectionContents(DataRefImpl Sec) const;
115 virtual bool isSectionText(DataRefImpl Sec) const;
118 COFFObjectFile(MemoryBuffer *Object);
119 virtual symbol_iterator begin_symbols() const;
120 virtual symbol_iterator end_symbols() const;
121 virtual section_iterator begin_sections() const;
122 virtual section_iterator end_sections() const;
124 virtual uint8_t getBytesInAddress() const;
125 virtual StringRef getFileFormatName() const;
126 virtual unsigned getArch() const;
130 SymbolRef COFFObjectFile::getSymbolNext(DataRefImpl Symb) const {
131 const coff_symbol *symb = reinterpret_cast<const coff_symbol*>(Symb.p);
132 symb += 1 + symb->NumberOfAuxSymbols;
133 Symb.p = reinterpret_cast<intptr_t>(symb);
134 return SymbolRef(Symb, this);
137 StringRef COFFObjectFile::getSymbolName(DataRefImpl Symb) const {
138 const coff_symbol *symb = reinterpret_cast<const coff_symbol*>(Symb.p);
139 // Check for string table entry. First 4 bytes are 0.
140 if (symb->Name.Offset.Zeroes == 0) {
141 uint32_t Offset = symb->Name.Offset.Offset;
142 return StringRef(getString(Offset));
145 if (symb->Name.ShortName[7] == 0)
146 // Null terminated, let ::strlen figure out the length.
147 return StringRef(symb->Name.ShortName);
148 // Not null terminated, use all 8 bytes.
149 return StringRef(symb->Name.ShortName, 8);
152 uint64_t COFFObjectFile::getSymbolAddress(DataRefImpl Symb) const {
153 const coff_symbol *symb = reinterpret_cast<const coff_symbol*>(Symb.p);
154 const coff_section *Section = getSection(symb->SectionNumber);
155 char Type = getSymbolNMTypeChar(Symb);
156 if (Type == 'U' || Type == 'w')
157 return UnknownAddressOrSize;
159 return Section->VirtualAddress + symb->Value;
163 uint64_t COFFObjectFile::getSymbolSize(DataRefImpl Symb) const {
164 // FIXME: Return the correct size. This requires looking at all the symbols
165 // in the same section as this symbol, and looking for either the next
166 // symbol, or the end of the section.
167 const coff_symbol *symb = reinterpret_cast<const coff_symbol*>(Symb.p);
168 const coff_section *Section = getSection(symb->SectionNumber);
169 char Type = getSymbolNMTypeChar(Symb);
170 if (Type == 'U' || Type == 'w')
171 return UnknownAddressOrSize;
173 return Section->SizeOfRawData - symb->Value;
177 char COFFObjectFile::getSymbolNMTypeChar(DataRefImpl Symb) const {
178 const coff_symbol *symb = reinterpret_cast<const coff_symbol*>(Symb.p);
179 char ret = StringSwitch<char>(getSymbolName(Symb))
180 .StartsWith(".debug", 'N')
181 .StartsWith(".sxdata", 'N')
187 uint32_t Characteristics = 0;
188 uint32_t PointerToRawData = 0;
189 const coff_section *Section = getSection(symb->SectionNumber);
191 Characteristics = Section->Characteristics;
192 PointerToRawData = Section->PointerToRawData;
195 switch (symb->SectionNumber) {
196 case COFF::IMAGE_SYM_UNDEFINED:
197 // Check storage classes.
198 if (symb->StorageClass == COFF::IMAGE_SYM_CLASS_WEAK_EXTERNAL)
199 return 'w'; // Don't do ::toupper.
203 case COFF::IMAGE_SYM_ABSOLUTE:
206 case COFF::IMAGE_SYM_DEBUG:
210 // Check section type.
211 if (Characteristics & COFF::IMAGE_SCN_CNT_CODE)
213 else if ( Characteristics & COFF::IMAGE_SCN_MEM_READ
214 && ~Characteristics & COFF::IMAGE_SCN_MEM_WRITE) // Read only.
216 else if (Characteristics & COFF::IMAGE_SCN_CNT_INITIALIZED_DATA)
218 else if (Characteristics & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA)
220 else if (Characteristics & COFF::IMAGE_SCN_LNK_INFO)
223 // Check for section symbol.
224 else if ( symb->StorageClass == COFF::IMAGE_SYM_CLASS_STATIC
229 if (symb->StorageClass == COFF::IMAGE_SYM_CLASS_EXTERNAL)
230 ret = ::toupper(ret);
235 bool COFFObjectFile::isSymbolInternal(DataRefImpl Symb) const {
239 SectionRef COFFObjectFile::getSectionNext(DataRefImpl Sec) const {
240 const coff_section *sec = reinterpret_cast<const coff_section*>(Sec.p);
242 Sec.p = reinterpret_cast<intptr_t>(sec);
243 return SectionRef(Sec, this);
246 StringRef COFFObjectFile::getSectionName(DataRefImpl Sec) const {
247 const coff_section *sec = reinterpret_cast<const coff_section*>(Sec.p);
249 if (sec->Name[7] == 0)
250 // Null terminated, let ::strlen figure out the length.
253 // Not null terminated, use all 8 bytes.
254 name = StringRef(sec->Name, 8);
256 // Check for string table entry. First byte is '/'.
257 if (name[0] == '/') {
259 name.getAsInteger(10, Offset);
260 return StringRef(getString(Offset));
263 // It's just a normal name.
267 uint64_t COFFObjectFile::getSectionAddress(DataRefImpl Sec) const {
268 const coff_section *sec = reinterpret_cast<const coff_section*>(Sec.p);
269 return sec->VirtualAddress;
272 uint64_t COFFObjectFile::getSectionSize(DataRefImpl Sec) const {
273 const coff_section *sec = reinterpret_cast<const coff_section*>(Sec.p);
274 return sec->SizeOfRawData;
277 StringRef COFFObjectFile::getSectionContents(DataRefImpl Sec) const {
278 const coff_section *sec = reinterpret_cast<const coff_section*>(Sec.p);
279 return StringRef(reinterpret_cast<const char *>(base + sec->PointerToRawData),
283 bool COFFObjectFile::isSectionText(DataRefImpl Sec) const {
284 const coff_section *sec = reinterpret_cast<const coff_section*>(Sec.p);
285 return sec->Characteristics & COFF::IMAGE_SCN_CNT_CODE;
288 COFFObjectFile::COFFObjectFile(MemoryBuffer *Object)
289 : ObjectFile(Object) {
290 Header = reinterpret_cast<const coff_file_header *>(base);
292 reinterpret_cast<const coff_section *>( base
293 + sizeof(coff_file_header)
294 + Header->SizeOfOptionalHeader);
296 reinterpret_cast<const coff_symbol *>(base + Header->PointerToSymbolTable);
298 // Find string table.
299 StringTable = reinterpret_cast<const char *>(base)
300 + Header->PointerToSymbolTable
301 + Header->NumberOfSymbols * 18;
304 ObjectFile::symbol_iterator COFFObjectFile::begin_symbols() const {
306 ret.p = reinterpret_cast<intptr_t>(SymbolTable);
307 return symbol_iterator(SymbolRef(ret, this));
310 ObjectFile::symbol_iterator COFFObjectFile::end_symbols() const {
311 // The symbol table ends where the string table begins.
313 ret.p = reinterpret_cast<intptr_t>(StringTable);
314 return symbol_iterator(SymbolRef(ret, this));
317 ObjectFile::section_iterator COFFObjectFile::begin_sections() const {
319 ret.p = reinterpret_cast<intptr_t>(SectionTable);
320 return section_iterator(SectionRef(ret, this));
323 ObjectFile::section_iterator COFFObjectFile::end_sections() const {
325 ret.p = reinterpret_cast<intptr_t>(SectionTable + Header->NumberOfSections);
326 return section_iterator(SectionRef(ret, this));
329 uint8_t COFFObjectFile::getBytesInAddress() const {
330 return getArch() == Triple::x86_64 ? 8 : 4;
333 StringRef COFFObjectFile::getFileFormatName() const {
334 switch(Header->Machine) {
335 case COFF::IMAGE_FILE_MACHINE_I386:
337 case COFF::IMAGE_FILE_MACHINE_AMD64:
338 return "COFF-x86-64";
340 return "COFF-<unknown arch>";
344 unsigned COFFObjectFile::getArch() const {
345 switch(Header->Machine) {
346 case COFF::IMAGE_FILE_MACHINE_I386:
348 case COFF::IMAGE_FILE_MACHINE_AMD64:
349 return Triple::x86_64;
351 return Triple::UnknownArch;
355 const coff_section *COFFObjectFile::getSection(std::size_t index) const {
356 if (index > 0 && index <= Header->NumberOfSections)
357 return SectionTable + (index - 1);
361 const char *COFFObjectFile::getString(std::size_t offset) const {
362 const ulittle32_t *StringTableSize =
363 reinterpret_cast<const ulittle32_t *>(StringTable);
364 if (offset < *StringTableSize)
365 return StringTable + offset;
371 ObjectFile *ObjectFile::createCOFFObjectFile(MemoryBuffer *Object) {
372 return new COFFObjectFile(Object);
375 } // end namespace llvm