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);
132 symb += 1 + symb->NumberOfAuxSymbols;
133 return SymbolRef(DataRefImpl(symb), this);
136 StringRef COFFObjectFile::getSymbolName(DataRefImpl Symb) const {
137 const coff_symbol *symb = *reinterpret_cast<const coff_symbol**>(&Symb);
138 // Check for string table entry. First 4 bytes are 0.
139 if (symb->Name.Offset.Zeroes == 0) {
140 uint32_t Offset = symb->Name.Offset.Offset;
141 return StringRef(getString(Offset));
144 if (symb->Name.ShortName[7] == 0)
145 // Null terminated, let ::strlen figure out the length.
146 return StringRef(symb->Name.ShortName);
147 // Not null terminated, use all 8 bytes.
148 return StringRef(symb->Name.ShortName, 8);
151 uint64_t COFFObjectFile::getSymbolAddress(DataRefImpl Symb) const {
152 const coff_symbol *symb = *reinterpret_cast<const coff_symbol**>(&Symb);
153 const coff_section *Section = getSection(symb->SectionNumber);
154 char Type = getSymbolNMTypeChar(Symb);
155 if (Type == 'U' || Type == 'w')
156 return UnknownAddressOrSize;
158 return Section->VirtualAddress + symb->Value;
162 uint64_t COFFObjectFile::getSymbolSize(DataRefImpl Symb) const {
163 // FIXME: Return the correct size. This requires looking at all the symbols
164 // in the same section as this symbol, and looking for either the next
165 // symbol, or the end of the section.
166 const coff_symbol *symb = *reinterpret_cast<const coff_symbol**>(&Symb);
167 const coff_section *Section = getSection(symb->SectionNumber);
168 char Type = getSymbolNMTypeChar(Symb);
169 if (Type == 'U' || Type == 'w')
170 return UnknownAddressOrSize;
172 return Section->SizeOfRawData - symb->Value;
176 char COFFObjectFile::getSymbolNMTypeChar(DataRefImpl Symb) const {
177 const coff_symbol *symb = *reinterpret_cast<const coff_symbol**>(&Symb);
178 char ret = StringSwitch<char>(getSymbolName(Symb))
179 .StartsWith(".debug", 'N')
180 .StartsWith(".sxdata", 'N')
186 uint32_t Characteristics = 0;
187 uint32_t PointerToRawData = 0;
188 const coff_section *Section = getSection(symb->SectionNumber);
190 Characteristics = Section->Characteristics;
191 PointerToRawData = Section->PointerToRawData;
194 switch (symb->SectionNumber) {
195 case COFF::IMAGE_SYM_UNDEFINED:
196 // Check storage classes.
197 if (symb->StorageClass == COFF::IMAGE_SYM_CLASS_WEAK_EXTERNAL)
198 return 'w'; // Don't do ::toupper.
202 case COFF::IMAGE_SYM_ABSOLUTE:
205 case COFF::IMAGE_SYM_DEBUG:
209 // Check section type.
210 if (Characteristics & COFF::IMAGE_SCN_CNT_CODE)
212 else if ( Characteristics & COFF::IMAGE_SCN_MEM_READ
213 && ~Characteristics & COFF::IMAGE_SCN_MEM_WRITE) // Read only.
215 else if (Characteristics & COFF::IMAGE_SCN_CNT_INITIALIZED_DATA)
217 else if (Characteristics & COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA)
219 else if (Characteristics & COFF::IMAGE_SCN_LNK_INFO)
222 // Check for section symbol.
223 else if ( symb->StorageClass == COFF::IMAGE_SYM_CLASS_STATIC
228 if (symb->StorageClass == COFF::IMAGE_SYM_CLASS_EXTERNAL)
229 ret = ::toupper(ret);
234 bool COFFObjectFile::isSymbolInternal(DataRefImpl Symb) const {
238 SectionRef COFFObjectFile::getSectionNext(DataRefImpl Sec) const {
239 const coff_section *sec = *reinterpret_cast<const coff_section**>(&Sec);
241 return SectionRef(DataRefImpl(sec), this);
244 StringRef COFFObjectFile::getSectionName(DataRefImpl Sec) const {
245 const coff_section *sec = *reinterpret_cast<const coff_section**>(&Sec);
247 if (sec->Name[7] == 0)
248 // Null terminated, let ::strlen figure out the length.
251 // Not null terminated, use all 8 bytes.
252 name = StringRef(sec->Name, 8);
254 // Check for string table entry. First byte is '/'.
255 if (name[0] == '/') {
257 name.getAsInteger(10, Offset);
258 return StringRef(getString(Offset));
261 // It's just a normal name.
265 uint64_t COFFObjectFile::getSectionAddress(DataRefImpl Sec) const {
266 const coff_section *sec = *reinterpret_cast<const coff_section**>(&Sec);
267 return sec->VirtualAddress;
270 uint64_t COFFObjectFile::getSectionSize(DataRefImpl Sec) const {
271 const coff_section *sec = *reinterpret_cast<const coff_section**>(&Sec);
272 return sec->SizeOfRawData;
275 StringRef COFFObjectFile::getSectionContents(DataRefImpl Sec) const {
276 const coff_section *sec = *reinterpret_cast<const coff_section**>(&Sec);
277 return StringRef(reinterpret_cast<const char *>(base + sec->PointerToRawData),
281 bool COFFObjectFile::isSectionText(DataRefImpl Sec) const {
282 const coff_section *sec = *reinterpret_cast<const coff_section**>(&Sec);
283 return sec->Characteristics & COFF::IMAGE_SCN_CNT_CODE;
286 COFFObjectFile::COFFObjectFile(MemoryBuffer *Object)
287 : ObjectFile(Object) {
288 Header = reinterpret_cast<const coff_file_header *>(base);
290 reinterpret_cast<const coff_section *>( base
291 + sizeof(coff_file_header)
292 + Header->SizeOfOptionalHeader);
294 reinterpret_cast<const coff_symbol *>(base + Header->PointerToSymbolTable);
296 // Find string table.
297 StringTable = reinterpret_cast<const char *>(base)
298 + Header->PointerToSymbolTable
299 + Header->NumberOfSymbols * 18;
302 ObjectFile::symbol_iterator COFFObjectFile::begin_symbols() const {
303 return symbol_iterator(
304 SymbolRef(DataRefImpl(SymbolTable), this));
307 ObjectFile::symbol_iterator COFFObjectFile::end_symbols() const {
308 // The symbol table ends where the string table begins.
309 return symbol_iterator(
310 SymbolRef(DataRefImpl(StringTable), this));
313 ObjectFile::section_iterator COFFObjectFile::begin_sections() const {
314 return section_iterator(
315 SectionRef(DataRefImpl(SectionTable), this));
318 ObjectFile::section_iterator COFFObjectFile::end_sections() const {
319 return section_iterator(
321 DataRefImpl((void *)(SectionTable + Header->NumberOfSections)), this));
324 uint8_t COFFObjectFile::getBytesInAddress() const {
328 StringRef COFFObjectFile::getFileFormatName() const {
329 switch(Header->Machine) {
330 case COFF::IMAGE_FILE_MACHINE_I386:
332 case COFF::IMAGE_FILE_MACHINE_AMD64:
333 return "COFF-x86-64";
335 return "COFF-<unknown arch>";
339 unsigned COFFObjectFile::getArch() const {
340 switch(Header->Machine) {
341 case COFF::IMAGE_FILE_MACHINE_I386:
343 case COFF::IMAGE_FILE_MACHINE_AMD64:
344 return Triple::x86_64;
346 return Triple::UnknownArch;
350 const coff_section *COFFObjectFile::getSection(std::size_t index) const {
351 if (index > 0 && index <= Header->NumberOfSections)
352 return SectionTable + (index - 1);
356 const char *COFFObjectFile::getString(std::size_t offset) const {
357 const ulittle32_t *StringTableSize =
358 reinterpret_cast<const ulittle32_t *>(StringTable);
359 if (offset < *StringTableSize)
360 return StringTable + offset;
366 ObjectFile *ObjectFile::createCOFFObjectFile(MemoryBuffer *Object) {
367 return new COFFObjectFile(Object);
370 } // end namespace llvm