forked from OSchip/llvm-project
490 lines
16 KiB
C++
490 lines
16 KiB
C++
//===- Librarian.cpp ------------------------------------------------------===//
|
|
//
|
|
// The LLVM Linker
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This file contains functions for the Librarian. The librarian creates and
|
|
// manages libraries of the Common Object File Format (COFF) object files. It
|
|
// primarily is used for creating static libraries and import libraries.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "Config.h"
|
|
#include "Driver.h"
|
|
#include "Error.h"
|
|
#include "Symbols.h"
|
|
#include "llvm/Object/Archive.h"
|
|
#include "llvm/Object/ArchiveWriter.h"
|
|
#include "llvm/Object/COFF.h"
|
|
#include "llvm/Support/Path.h"
|
|
|
|
#include <vector>
|
|
|
|
using namespace lld::coff;
|
|
using namespace llvm::COFF;
|
|
using namespace llvm::object;
|
|
using namespace llvm;
|
|
|
|
static bool is32bit() {
|
|
switch (Config->Machine) {
|
|
default:
|
|
llvm_unreachable("unsupported machine");
|
|
case IMAGE_FILE_MACHINE_AMD64:
|
|
return false;
|
|
case IMAGE_FILE_MACHINE_ARMNT:
|
|
case IMAGE_FILE_MACHINE_I386:
|
|
return true;
|
|
}
|
|
}
|
|
|
|
static uint16_t getImgRelRelocation() {
|
|
switch (Config->Machine) {
|
|
default:
|
|
llvm_unreachable("unsupported machine");
|
|
case IMAGE_FILE_MACHINE_AMD64:
|
|
return IMAGE_REL_AMD64_ADDR32NB;
|
|
case IMAGE_FILE_MACHINE_ARMNT:
|
|
return IMAGE_REL_ARM_ADDR32NB;
|
|
case IMAGE_FILE_MACHINE_I386:
|
|
return IMAGE_REL_I386_DIR32NB;
|
|
}
|
|
}
|
|
|
|
template <class T> static void append(std::vector<uint8_t> &B, const T &Data) {
|
|
size_t S = B.size();
|
|
B.resize(S + sizeof(T));
|
|
memcpy(&B[S], &Data, sizeof(T));
|
|
}
|
|
|
|
static void writeStringTable(std::vector<uint8_t> &B,
|
|
ArrayRef<const std::string> Strings) {
|
|
// The COFF string table consists of a 4-byte value which is the size of the
|
|
// table, including the length field itself. This value is followed by the
|
|
// string content itself, which is an array of null-terminated C-style
|
|
// strings. The termination is important as they are referenced to by offset
|
|
// by the symbol entity in the file format.
|
|
|
|
std::vector<uint8_t>::size_type Pos = B.size();
|
|
std::vector<uint8_t>::size_type Offset = B.size();
|
|
|
|
// Skip over the length field, we will fill it in later as we will have
|
|
// computed the length while emitting the string content itself.
|
|
Pos += sizeof(uint32_t);
|
|
|
|
for (const auto &S : Strings) {
|
|
B.resize(Pos + S.length() + 1);
|
|
strcpy(reinterpret_cast<char *>(&B[Pos]), S.c_str());
|
|
Pos += S.length() + 1;
|
|
}
|
|
|
|
// Backfill the length of the table now that it has been computed.
|
|
support::ulittle32_t Length(B.size() - Offset);
|
|
memcpy(&B[Offset], &Length, sizeof(Length));
|
|
}
|
|
|
|
static std::string getImplibPath() {
|
|
if (!Config->Implib.empty())
|
|
return Config->Implib;
|
|
SmallString<128> Out = StringRef(Config->OutputFile);
|
|
sys::path::replace_extension(Out, ".lib");
|
|
return Out.str();
|
|
}
|
|
|
|
static ImportNameType getNameType(StringRef Sym, StringRef ExtName) {
|
|
if (Sym != ExtName)
|
|
return IMPORT_NAME_UNDECORATE;
|
|
if (Config->Machine == I386 && Sym.startswith("_"))
|
|
return IMPORT_NAME_NOPREFIX;
|
|
return IMPORT_NAME;
|
|
}
|
|
|
|
static std::string replace(StringRef S, StringRef From, StringRef To) {
|
|
size_t Pos = S.find(From);
|
|
assert(Pos != StringRef::npos);
|
|
return (Twine(S.substr(0, Pos)) + To + S.substr(Pos + From.size())).str();
|
|
}
|
|
|
|
static const std::string NullImportDescriptorSymbolName =
|
|
"__NULL_IMPORT_DESCRIPTOR";
|
|
|
|
namespace {
|
|
// This class constructs various small object files necessary to support linking
|
|
// symbols imported from a DLL. The contents are pretty strictly defined and
|
|
// nearly entirely static. The details of the structures files are defined in
|
|
// WINNT.h and the PE/COFF specification.
|
|
class ObjectFactory {
|
|
using u16 = support::ulittle16_t;
|
|
using u32 = support::ulittle32_t;
|
|
|
|
BumpPtrAllocator Alloc;
|
|
StringRef DLLName;
|
|
StringRef Library;
|
|
std::string ImportDescriptorSymbolName;
|
|
std::string NullThunkSymbolName;
|
|
|
|
public:
|
|
ObjectFactory(StringRef S)
|
|
: DLLName(S), Library(S.drop_back(4)),
|
|
ImportDescriptorSymbolName(("__IMPORT_DESCRIPTOR_" + Library).str()),
|
|
NullThunkSymbolName(("\x7f" + Library + "_NULL_THUNK_DATA").str()) {}
|
|
|
|
// Creates an Import Descriptor. This is a small object file which contains a
|
|
// reference to the terminators and contains the library name (entry) for the
|
|
// import name table. It will force the linker to construct the necessary
|
|
// structure to import symbols from the DLL.
|
|
NewArchiveMember createImportDescriptor(std::vector<uint8_t> &Buffer);
|
|
|
|
// Creates a NULL import descriptor. This is a small object file whcih
|
|
// contains a NULL import descriptor. It is used to terminate the imports
|
|
// from a specific DLL.
|
|
NewArchiveMember createNullImportDescriptor(std::vector<uint8_t> &Buffer);
|
|
|
|
// Create a NULL Thunk Entry. This is a small object file which contains a
|
|
// NULL Import Address Table entry and a NULL Import Lookup Table Entry. It
|
|
// is used to terminate the IAT and ILT.
|
|
NewArchiveMember createNullThunk(std::vector<uint8_t> &Buffer);
|
|
|
|
// Create a short import file which is described in PE/COFF spec 7. Import
|
|
// Library Format.
|
|
NewArchiveMember createShortImport(StringRef Sym, uint16_t Ordinal,
|
|
ImportNameType NameType, bool isData);
|
|
};
|
|
}
|
|
|
|
NewArchiveMember
|
|
ObjectFactory::createImportDescriptor(std::vector<uint8_t> &Buffer) {
|
|
static const uint32_t NumberOfSections = 2;
|
|
static const uint32_t NumberOfSymbols = 7;
|
|
static const uint32_t NumberOfRelocations = 3;
|
|
|
|
// COFF Header
|
|
coff_file_header Header{
|
|
u16(Config->Machine), u16(NumberOfSections), u32(0),
|
|
u32(sizeof(Header) + (NumberOfSections * sizeof(coff_section)) +
|
|
// .idata$2
|
|
sizeof(coff_import_directory_table_entry) +
|
|
NumberOfRelocations * sizeof(coff_relocation) +
|
|
// .idata$4
|
|
(DLLName.size() + 1)),
|
|
u32(NumberOfSymbols), u16(0),
|
|
u16(is32bit() ? IMAGE_FILE_32BIT_MACHINE : 0),
|
|
};
|
|
append(Buffer, Header);
|
|
|
|
// Section Header Table
|
|
static const coff_section SectionTable[NumberOfSections] = {
|
|
{{'.', 'i', 'd', 'a', 't', 'a', '$', '2'},
|
|
u32(0),
|
|
u32(0),
|
|
u32(sizeof(coff_import_directory_table_entry)),
|
|
u32(sizeof(coff_file_header) + NumberOfSections * sizeof(coff_section)),
|
|
u32(sizeof(coff_file_header) + NumberOfSections * sizeof(coff_section) +
|
|
sizeof(coff_import_directory_table_entry)),
|
|
u32(0),
|
|
u16(NumberOfRelocations),
|
|
u16(0),
|
|
u32(IMAGE_SCN_ALIGN_4BYTES | IMAGE_SCN_CNT_INITIALIZED_DATA |
|
|
IMAGE_SCN_MEM_READ | IMAGE_SCN_MEM_WRITE)},
|
|
{{'.', 'i', 'd', 'a', 't', 'a', '$', '6'},
|
|
u32(0),
|
|
u32(0),
|
|
u32(DLLName.size() + 1),
|
|
u32(sizeof(coff_file_header) + NumberOfSections * sizeof(coff_section) +
|
|
sizeof(coff_import_directory_table_entry) +
|
|
NumberOfRelocations * sizeof(coff_relocation)),
|
|
u32(0),
|
|
u32(0),
|
|
u16(0),
|
|
u16(0),
|
|
u32(IMAGE_SCN_ALIGN_2BYTES | IMAGE_SCN_CNT_INITIALIZED_DATA |
|
|
IMAGE_SCN_MEM_READ | IMAGE_SCN_MEM_WRITE)},
|
|
};
|
|
append(Buffer, SectionTable);
|
|
|
|
// .idata$2
|
|
static const coff_import_directory_table_entry ImportDescriptor{
|
|
u32(0), u32(0), u32(0), u32(0), u32(0),
|
|
};
|
|
append(Buffer, ImportDescriptor);
|
|
|
|
static const coff_relocation RelocationTable[NumberOfRelocations] = {
|
|
{u32(offsetof(coff_import_directory_table_entry, NameRVA)), u32(2),
|
|
u16(getImgRelRelocation())},
|
|
{u32(offsetof(coff_import_directory_table_entry, ImportLookupTableRVA)),
|
|
u32(3), u16(getImgRelRelocation())},
|
|
{u32(offsetof(coff_import_directory_table_entry, ImportAddressTableRVA)),
|
|
u32(4), u16(getImgRelRelocation())},
|
|
};
|
|
append(Buffer, RelocationTable);
|
|
|
|
// .idata$6
|
|
auto S = Buffer.size();
|
|
Buffer.resize(S + DLLName.size() + 1);
|
|
memcpy(&Buffer[S], DLLName.data(), DLLName.size());
|
|
Buffer[S + DLLName.size()] = '\0';
|
|
|
|
// Symbol Table
|
|
coff_symbol16 SymbolTable[NumberOfSymbols] = {
|
|
{{{0, 0, 0, 0, 0, 0, 0, 0}},
|
|
u32(0),
|
|
u16(1),
|
|
u16(0),
|
|
IMAGE_SYM_CLASS_EXTERNAL,
|
|
0},
|
|
{{{'.', 'i', 'd', 'a', 't', 'a', '$', '2'}},
|
|
u32(0),
|
|
u16(1),
|
|
u16(0),
|
|
IMAGE_SYM_CLASS_SECTION,
|
|
0},
|
|
{{{'.', 'i', 'd', 'a', 't', 'a', '$', '6'}},
|
|
u32(0),
|
|
u16(2),
|
|
u16(0),
|
|
IMAGE_SYM_CLASS_STATIC,
|
|
0},
|
|
{{{'.', 'i', 'd', 'a', 't', 'a', '$', '4'}},
|
|
u32(0),
|
|
u16(0),
|
|
u16(0),
|
|
IMAGE_SYM_CLASS_SECTION,
|
|
0},
|
|
{{{'.', 'i', 'd', 'a', 't', 'a', '$', '5'}},
|
|
u32(0),
|
|
u16(0),
|
|
u16(0),
|
|
IMAGE_SYM_CLASS_SECTION,
|
|
0},
|
|
{{{0, 0, 0, 0, 0, 0, 0, 0}},
|
|
u32(0),
|
|
u16(0),
|
|
u16(0),
|
|
IMAGE_SYM_CLASS_EXTERNAL,
|
|
0},
|
|
{{{0, 0, 0, 0, 0, 0, 0, 0}},
|
|
u32(0),
|
|
u16(0),
|
|
u16(0),
|
|
IMAGE_SYM_CLASS_EXTERNAL,
|
|
0},
|
|
};
|
|
reinterpret_cast<StringTableOffset &>(SymbolTable[0].Name).Offset =
|
|
sizeof(uint32_t);
|
|
reinterpret_cast<StringTableOffset &>(SymbolTable[5].Name).Offset =
|
|
sizeof(uint32_t) + ImportDescriptorSymbolName.length() + 1;
|
|
reinterpret_cast<StringTableOffset &>(SymbolTable[6].Name).Offset =
|
|
sizeof(uint32_t) + ImportDescriptorSymbolName.length() + 1 +
|
|
NullImportDescriptorSymbolName.length() + 1;
|
|
append(Buffer, SymbolTable);
|
|
|
|
// String Table
|
|
writeStringTable(Buffer,
|
|
{ImportDescriptorSymbolName, NullImportDescriptorSymbolName,
|
|
NullThunkSymbolName});
|
|
|
|
StringRef F{reinterpret_cast<const char *>(Buffer.data()), Buffer.size()};
|
|
return {MemoryBufferRef(F, DLLName)};
|
|
}
|
|
|
|
NewArchiveMember
|
|
ObjectFactory::createNullImportDescriptor(std::vector<uint8_t> &Buffer) {
|
|
static const uint32_t NumberOfSections = 1;
|
|
static const uint32_t NumberOfSymbols = 1;
|
|
|
|
// COFF Header
|
|
coff_file_header Header{
|
|
u16(Config->Machine), u16(NumberOfSections), u32(0),
|
|
u32(sizeof(Header) + (NumberOfSections * sizeof(coff_section)) +
|
|
// .idata$3
|
|
sizeof(coff_import_directory_table_entry)),
|
|
u32(NumberOfSymbols), u16(0),
|
|
u16(is32bit() ? IMAGE_FILE_32BIT_MACHINE : 0),
|
|
};
|
|
append(Buffer, Header);
|
|
|
|
// Section Header Table
|
|
static const coff_section SectionTable[NumberOfSections] = {
|
|
{{'.', 'i', 'd', 'a', 't', 'a', '$', '3'},
|
|
u32(0),
|
|
u32(0),
|
|
u32(sizeof(coff_import_directory_table_entry)),
|
|
u32(sizeof(coff_file_header) +
|
|
(NumberOfSections * sizeof(coff_section))),
|
|
u32(0),
|
|
u32(0),
|
|
u16(0),
|
|
u16(0),
|
|
u32(IMAGE_SCN_ALIGN_4BYTES | IMAGE_SCN_CNT_INITIALIZED_DATA |
|
|
IMAGE_SCN_MEM_READ | IMAGE_SCN_MEM_WRITE)},
|
|
};
|
|
append(Buffer, SectionTable);
|
|
|
|
// .idata$3
|
|
static const coff_import_directory_table_entry ImportDescriptor{
|
|
u32(0), u32(0), u32(0), u32(0), u32(0),
|
|
};
|
|
append(Buffer, ImportDescriptor);
|
|
|
|
// Symbol Table
|
|
coff_symbol16 SymbolTable[NumberOfSymbols] = {
|
|
{{{0, 0, 0, 0, 0, 0, 0, 0}},
|
|
u32(0),
|
|
u16(1),
|
|
u16(0),
|
|
IMAGE_SYM_CLASS_EXTERNAL,
|
|
0},
|
|
};
|
|
reinterpret_cast<StringTableOffset &>(SymbolTable[0].Name).Offset =
|
|
sizeof(uint32_t);
|
|
append(Buffer, SymbolTable);
|
|
|
|
// String Table
|
|
writeStringTable(Buffer, {NullImportDescriptorSymbolName});
|
|
|
|
StringRef F{reinterpret_cast<const char *>(Buffer.data()), Buffer.size()};
|
|
return {MemoryBufferRef(F, DLLName)};
|
|
}
|
|
|
|
NewArchiveMember ObjectFactory::createNullThunk(std::vector<uint8_t> &Buffer) {
|
|
static const uint32_t NumberOfSections = 2;
|
|
static const uint32_t NumberOfSymbols = 1;
|
|
|
|
// COFF Header
|
|
coff_file_header Header{
|
|
u16(Config->Machine), u16(NumberOfSections), u32(0),
|
|
u32(sizeof(Header) + (NumberOfSections * sizeof(coff_section)) +
|
|
// .idata$5
|
|
sizeof(export_address_table_entry) +
|
|
// .idata$4
|
|
sizeof(export_address_table_entry)),
|
|
u32(NumberOfSymbols), u16(0),
|
|
u16(is32bit() ? IMAGE_FILE_32BIT_MACHINE : 0),
|
|
};
|
|
append(Buffer, Header);
|
|
|
|
// Section Header Table
|
|
static const coff_section SectionTable[NumberOfSections] = {
|
|
{{'.', 'i', 'd', 'a', 't', 'a', '$', '5'},
|
|
u32(0),
|
|
u32(0),
|
|
u32(sizeof(export_address_table_entry)),
|
|
u32(sizeof(coff_file_header) + NumberOfSections * sizeof(coff_section)),
|
|
u32(0),
|
|
u32(0),
|
|
u16(0),
|
|
u16(0),
|
|
u32(IMAGE_SCN_ALIGN_4BYTES | IMAGE_SCN_CNT_INITIALIZED_DATA |
|
|
IMAGE_SCN_MEM_READ | IMAGE_SCN_MEM_WRITE)},
|
|
{{'.', 'i', 'd', 'a', 't', 'a', '$', '4'},
|
|
u32(0),
|
|
u32(0),
|
|
u32(sizeof(export_address_table_entry)),
|
|
u32(sizeof(coff_file_header) + NumberOfSections * sizeof(coff_section) +
|
|
sizeof(export_address_table_entry)),
|
|
u32(0),
|
|
u32(0),
|
|
u16(0),
|
|
u16(0),
|
|
u32(IMAGE_SCN_ALIGN_4BYTES | IMAGE_SCN_CNT_INITIALIZED_DATA |
|
|
IMAGE_SCN_MEM_READ | IMAGE_SCN_MEM_WRITE)},
|
|
};
|
|
append(Buffer, SectionTable);
|
|
|
|
// .idata$5
|
|
static const export_address_table_entry ILT{u32(0)};
|
|
append(Buffer, ILT);
|
|
|
|
// .idata$4
|
|
static const export_address_table_entry IAT{u32(0)};
|
|
append(Buffer, IAT);
|
|
|
|
// Symbol Table
|
|
coff_symbol16 SymbolTable[NumberOfSymbols] = {
|
|
{{{0, 0, 0, 0, 0, 0, 0, 0}},
|
|
u32(0),
|
|
u16(1),
|
|
u16(0),
|
|
IMAGE_SYM_CLASS_EXTERNAL,
|
|
0},
|
|
};
|
|
reinterpret_cast<StringTableOffset &>(SymbolTable[0].Name).Offset =
|
|
sizeof(uint32_t);
|
|
append(Buffer, SymbolTable);
|
|
|
|
// String Table
|
|
writeStringTable(Buffer, {NullThunkSymbolName});
|
|
|
|
StringRef F{reinterpret_cast<const char *>(Buffer.data()), Buffer.size()};
|
|
return {MemoryBufferRef{F, DLLName}};
|
|
}
|
|
|
|
NewArchiveMember ObjectFactory::createShortImport(StringRef Sym,
|
|
uint16_t Ordinal,
|
|
ImportNameType NameType,
|
|
bool isData) {
|
|
size_t ImpSize = DLLName.size() + Sym.size() + 2; // +2 for NULs
|
|
size_t Size = sizeof(coff_import_header) + ImpSize;
|
|
char *Buf = Alloc.Allocate<char>(Size);
|
|
memset(Buf, 0, Size);
|
|
char *P = Buf;
|
|
|
|
// Write short import library.
|
|
auto *Imp = reinterpret_cast<coff_import_header *>(P);
|
|
P += sizeof(*Imp);
|
|
Imp->Sig2 = 0xFFFF;
|
|
Imp->Machine = Config->Machine;
|
|
Imp->SizeOfData = ImpSize;
|
|
if (Ordinal > 0)
|
|
Imp->OrdinalHint = Ordinal;
|
|
Imp->TypeInfo = (isData ? IMPORT_DATA : IMPORT_CODE);
|
|
Imp->TypeInfo |= NameType << 2;
|
|
|
|
// Write symbol name and DLL name.
|
|
memcpy(P, Sym.data(), Sym.size());
|
|
P += Sym.size() + 1;
|
|
memcpy(P, DLLName.data(), DLLName.size());
|
|
|
|
return {MemoryBufferRef(StringRef(Buf, Size), DLLName)};
|
|
}
|
|
|
|
// Creates an import library for a DLL. In this function, we first
|
|
// create an empty import library using lib.exe and then adds short
|
|
// import files to that file.
|
|
void lld::coff::writeImportLibrary() {
|
|
std::vector<NewArchiveMember> Members;
|
|
|
|
std::string Path = getImplibPath();
|
|
std::string DLLName = llvm::sys::path::filename(Config->OutputFile);
|
|
ObjectFactory OF(DLLName);
|
|
|
|
std::vector<uint8_t> ImportDescriptor;
|
|
Members.push_back(OF.createImportDescriptor(ImportDescriptor));
|
|
|
|
std::vector<uint8_t> NullImportDescriptor;
|
|
Members.push_back(OF.createNullImportDescriptor(NullImportDescriptor));
|
|
|
|
std::vector<uint8_t> NullThunk;
|
|
Members.push_back(OF.createNullThunk(NullThunk));
|
|
|
|
for (Export &E : Config->Exports) {
|
|
if (E.Private)
|
|
continue;
|
|
|
|
ImportNameType Type = getNameType(E.SymbolName, E.Name);
|
|
std::string Name = E.ExtName.empty()
|
|
? std::string(E.SymbolName)
|
|
: replace(E.SymbolName, E.Name, E.ExtName);
|
|
Members.push_back(OF.createShortImport(Name, E.Ordinal, Type, E.Data));
|
|
}
|
|
|
|
std::pair<StringRef, std::error_code> Result =
|
|
writeArchive(Path, Members, /*WriteSymtab*/ true, object::Archive::K_GNU,
|
|
/*Deterministic*/ true, /*Thin*/ false);
|
|
if (auto EC = Result.second)
|
|
fatal(EC, "failed to write " + Path);
|
|
}
|