/
ObjectFileELF.cpp
2923 lines (2549 loc) · 107 KB
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ObjectFileELF.cpp
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//===-- ObjectFileELF.cpp ------------------------------------- -*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "ObjectFileELF.h"
#include <cassert>
#include <algorithm>
#include "lldb/Core/ArchSpec.h"
#include "lldb/Core/DataBuffer.h"
#include "lldb/Core/Error.h"
#include "lldb/Core/FileSpecList.h"
#include "lldb/Core/Log.h"
#include "lldb/Core/Module.h"
#include "lldb/Core/ModuleSpec.h"
#include "lldb/Core/PluginManager.h"
#include "lldb/Core/Section.h"
#include "lldb/Core/Stream.h"
#include "lldb/Core/Timer.h"
#include "lldb/Symbol/DWARFCallFrameInfo.h"
#include "lldb/Symbol/SymbolContext.h"
#include "lldb/Target/SectionLoadList.h"
#include "lldb/Target/Target.h"
#include "lldb/Host/HostInfo.h"
#include "llvm/ADT/PointerUnion.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/Support/MathExtras.h"
#define CASE_AND_STREAM(s, def, width) \
case def: s->Printf("%-*s", width, #def); break;
using namespace lldb;
using namespace lldb_private;
using namespace elf;
using namespace llvm::ELF;
namespace {
// ELF note owner definitions
const char *const LLDB_NT_OWNER_FREEBSD = "FreeBSD";
const char *const LLDB_NT_OWNER_GNU = "GNU";
const char *const LLDB_NT_OWNER_NETBSD = "NetBSD";
const char *const LLDB_NT_OWNER_CSR = "csr";
const char *const LLDB_NT_OWNER_ANDROID = "Android";
// ELF note type definitions
const elf_word LLDB_NT_FREEBSD_ABI_TAG = 0x01;
const elf_word LLDB_NT_FREEBSD_ABI_SIZE = 4;
const elf_word LLDB_NT_GNU_ABI_TAG = 0x01;
const elf_word LLDB_NT_GNU_ABI_SIZE = 16;
const elf_word LLDB_NT_GNU_BUILD_ID_TAG = 0x03;
const elf_word LLDB_NT_NETBSD_ABI_TAG = 0x01;
const elf_word LLDB_NT_NETBSD_ABI_SIZE = 4;
// GNU ABI note OS constants
const elf_word LLDB_NT_GNU_ABI_OS_LINUX = 0x00;
const elf_word LLDB_NT_GNU_ABI_OS_HURD = 0x01;
const elf_word LLDB_NT_GNU_ABI_OS_SOLARIS = 0x02;
//===----------------------------------------------------------------------===//
/// @class ELFRelocation
/// @brief Generic wrapper for ELFRel and ELFRela.
///
/// This helper class allows us to parse both ELFRel and ELFRela relocation
/// entries in a generic manner.
class ELFRelocation
{
public:
/// Constructs an ELFRelocation entry with a personality as given by @p
/// type.
///
/// @param type Either DT_REL or DT_RELA. Any other value is invalid.
ELFRelocation(unsigned type);
~ELFRelocation();
bool
Parse(const lldb_private::DataExtractor &data, lldb::offset_t *offset);
static unsigned
RelocType32(const ELFRelocation &rel);
static unsigned
RelocType64(const ELFRelocation &rel);
static unsigned
RelocSymbol32(const ELFRelocation &rel);
static unsigned
RelocSymbol64(const ELFRelocation &rel);
static unsigned
RelocOffset32(const ELFRelocation &rel);
static unsigned
RelocOffset64(const ELFRelocation &rel);
static unsigned
RelocAddend32(const ELFRelocation &rel);
static unsigned
RelocAddend64(const ELFRelocation &rel);
private:
typedef llvm::PointerUnion<ELFRel*, ELFRela*> RelocUnion;
RelocUnion reloc;
};
ELFRelocation::ELFRelocation(unsigned type)
{
if (type == DT_REL || type == SHT_REL)
reloc = new ELFRel();
else if (type == DT_RELA || type == SHT_RELA)
reloc = new ELFRela();
else {
assert(false && "unexpected relocation type");
reloc = static_cast<ELFRel*>(NULL);
}
}
ELFRelocation::~ELFRelocation()
{
if (reloc.is<ELFRel*>())
delete reloc.get<ELFRel*>();
else
delete reloc.get<ELFRela*>();
}
bool
ELFRelocation::Parse(const lldb_private::DataExtractor &data, lldb::offset_t *offset)
{
if (reloc.is<ELFRel*>())
return reloc.get<ELFRel*>()->Parse(data, offset);
else
return reloc.get<ELFRela*>()->Parse(data, offset);
}
unsigned
ELFRelocation::RelocType32(const ELFRelocation &rel)
{
if (rel.reloc.is<ELFRel*>())
return ELFRel::RelocType32(*rel.reloc.get<ELFRel*>());
else
return ELFRela::RelocType32(*rel.reloc.get<ELFRela*>());
}
unsigned
ELFRelocation::RelocType64(const ELFRelocation &rel)
{
if (rel.reloc.is<ELFRel*>())
return ELFRel::RelocType64(*rel.reloc.get<ELFRel*>());
else
return ELFRela::RelocType64(*rel.reloc.get<ELFRela*>());
}
unsigned
ELFRelocation::RelocSymbol32(const ELFRelocation &rel)
{
if (rel.reloc.is<ELFRel*>())
return ELFRel::RelocSymbol32(*rel.reloc.get<ELFRel*>());
else
return ELFRela::RelocSymbol32(*rel.reloc.get<ELFRela*>());
}
unsigned
ELFRelocation::RelocSymbol64(const ELFRelocation &rel)
{
if (rel.reloc.is<ELFRel*>())
return ELFRel::RelocSymbol64(*rel.reloc.get<ELFRel*>());
else
return ELFRela::RelocSymbol64(*rel.reloc.get<ELFRela*>());
}
unsigned
ELFRelocation::RelocOffset32(const ELFRelocation &rel)
{
if (rel.reloc.is<ELFRel*>())
return rel.reloc.get<ELFRel*>()->r_offset;
else
return rel.reloc.get<ELFRela*>()->r_offset;
}
unsigned
ELFRelocation::RelocOffset64(const ELFRelocation &rel)
{
if (rel.reloc.is<ELFRel*>())
return rel.reloc.get<ELFRel*>()->r_offset;
else
return rel.reloc.get<ELFRela*>()->r_offset;
}
unsigned
ELFRelocation::RelocAddend32(const ELFRelocation &rel)
{
if (rel.reloc.is<ELFRel*>())
return 0;
else
return rel.reloc.get<ELFRela*>()->r_addend;
}
unsigned
ELFRelocation::RelocAddend64(const ELFRelocation &rel)
{
if (rel.reloc.is<ELFRel*>())
return 0;
else
return rel.reloc.get<ELFRela*>()->r_addend;
}
} // end anonymous namespace
bool
ELFNote::Parse(const DataExtractor &data, lldb::offset_t *offset)
{
// Read all fields.
if (data.GetU32(offset, &n_namesz, 3) == NULL)
return false;
// The name field is required to be nul-terminated, and n_namesz
// includes the terminating nul in observed implementations (contrary
// to the ELF-64 spec). A special case is needed for cores generated
// by some older Linux versions, which write a note named "CORE"
// without a nul terminator and n_namesz = 4.
if (n_namesz == 4)
{
char buf[4];
if (data.ExtractBytes (*offset, 4, data.GetByteOrder(), buf) != 4)
return false;
if (strncmp (buf, "CORE", 4) == 0)
{
n_name = "CORE";
*offset += 4;
return true;
}
}
const char *cstr = data.GetCStr(offset, llvm::RoundUpToAlignment (n_namesz, 4));
if (cstr == NULL)
{
Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_SYMBOLS));
if (log)
log->Printf("Failed to parse note name lacking nul terminator");
return false;
}
n_name = cstr;
return true;
}
static uint32_t
kalimbaVariantFromElfFlags(const elf::elf_word e_flags)
{
const uint32_t dsp_rev = e_flags & 0xFF;
uint32_t kal_arch_variant = LLDB_INVALID_CPUTYPE;
switch(dsp_rev)
{
// TODO(mg11) Support more variants
case 10:
kal_arch_variant = llvm::Triple::KalimbaSubArch_v3;
break;
case 14:
kal_arch_variant = llvm::Triple::KalimbaSubArch_v4;
break;
case 17:
case 20:
kal_arch_variant = llvm::Triple::KalimbaSubArch_v5;
break;
default:
break;
}
return kal_arch_variant;
}
static uint32_t
mipsVariantFromElfFlags(const elf::elf_word e_flags, uint32_t endian)
{
const uint32_t mips_arch = e_flags & llvm::ELF::EF_MIPS_ARCH;
uint32_t arch_variant = LLDB_INVALID_CPUTYPE;
switch (mips_arch)
{
case llvm::ELF::EF_MIPS_ARCH_64:
if (endian == ELFDATA2LSB)
arch_variant = llvm::Triple::mips64el;
else
arch_variant = llvm::Triple::mips64;
break;
default:
break;
}
return arch_variant;
}
static uint32_t
subTypeFromElfHeader(const elf::ELFHeader& header)
{
if (header.e_machine == llvm::ELF::EM_MIPS)
return mipsVariantFromElfFlags (header.e_flags,
header.e_ident[EI_DATA]);
return
llvm::ELF::EM_CSR_KALIMBA == header.e_machine ?
kalimbaVariantFromElfFlags(header.e_flags) :
LLDB_INVALID_CPUTYPE;
}
//! The kalimba toolchain identifies a code section as being
//! one with the SHT_PROGBITS set in the section sh_type and the top
//! bit in the 32-bit address field set.
static lldb::SectionType
kalimbaSectionType(
const elf::ELFHeader& header,
const elf::ELFSectionHeader& sect_hdr)
{
if (llvm::ELF::EM_CSR_KALIMBA != header.e_machine)
{
return eSectionTypeOther;
}
if (llvm::ELF::SHT_NOBITS == sect_hdr.sh_type)
{
return eSectionTypeZeroFill;
}
if (llvm::ELF::SHT_PROGBITS == sect_hdr.sh_type)
{
const lldb::addr_t KAL_CODE_BIT = 1 << 31;
return KAL_CODE_BIT & sect_hdr.sh_addr ?
eSectionTypeCode : eSectionTypeData;
}
return eSectionTypeOther;
}
// Arbitrary constant used as UUID prefix for core files.
const uint32_t
ObjectFileELF::g_core_uuid_magic(0xE210C);
//------------------------------------------------------------------
// Static methods.
//------------------------------------------------------------------
void
ObjectFileELF::Initialize()
{
PluginManager::RegisterPlugin(GetPluginNameStatic(),
GetPluginDescriptionStatic(),
CreateInstance,
CreateMemoryInstance,
GetModuleSpecifications);
}
void
ObjectFileELF::Terminate()
{
PluginManager::UnregisterPlugin(CreateInstance);
}
lldb_private::ConstString
ObjectFileELF::GetPluginNameStatic()
{
static ConstString g_name("elf");
return g_name;
}
const char *
ObjectFileELF::GetPluginDescriptionStatic()
{
return "ELF object file reader.";
}
ObjectFile *
ObjectFileELF::CreateInstance (const lldb::ModuleSP &module_sp,
DataBufferSP &data_sp,
lldb::offset_t data_offset,
const lldb_private::FileSpec* file,
lldb::offset_t file_offset,
lldb::offset_t length)
{
if (!data_sp)
{
data_sp = file->MemoryMapFileContentsIfLocal(file_offset, length);
data_offset = 0;
}
if (data_sp && data_sp->GetByteSize() > (llvm::ELF::EI_NIDENT + data_offset))
{
const uint8_t *magic = data_sp->GetBytes() + data_offset;
if (ELFHeader::MagicBytesMatch(magic))
{
// Update the data to contain the entire file if it doesn't already
if (data_sp->GetByteSize() < length) {
data_sp = file->MemoryMapFileContentsIfLocal(file_offset, length);
data_offset = 0;
magic = data_sp->GetBytes();
}
unsigned address_size = ELFHeader::AddressSizeInBytes(magic);
if (address_size == 4 || address_size == 8)
{
std::unique_ptr<ObjectFileELF> objfile_ap(new ObjectFileELF(module_sp, data_sp, data_offset, file, file_offset, length));
ArchSpec spec;
if (objfile_ap->GetArchitecture(spec) &&
objfile_ap->SetModulesArchitecture(spec))
return objfile_ap.release();
}
}
}
return NULL;
}
ObjectFile*
ObjectFileELF::CreateMemoryInstance (const lldb::ModuleSP &module_sp,
DataBufferSP& data_sp,
const lldb::ProcessSP &process_sp,
lldb::addr_t header_addr)
{
if (data_sp && data_sp->GetByteSize() > (llvm::ELF::EI_NIDENT))
{
const uint8_t *magic = data_sp->GetBytes();
if (ELFHeader::MagicBytesMatch(magic))
{
unsigned address_size = ELFHeader::AddressSizeInBytes(magic);
if (address_size == 4 || address_size == 8)
{
std::auto_ptr<ObjectFileELF> objfile_ap(new ObjectFileELF(module_sp, data_sp, process_sp, header_addr));
ArchSpec spec;
if (objfile_ap->GetArchitecture(spec) &&
objfile_ap->SetModulesArchitecture(spec))
return objfile_ap.release();
}
}
}
return NULL;
}
bool
ObjectFileELF::MagicBytesMatch (DataBufferSP& data_sp,
lldb::addr_t data_offset,
lldb::addr_t data_length)
{
if (data_sp && data_sp->GetByteSize() > (llvm::ELF::EI_NIDENT + data_offset))
{
const uint8_t *magic = data_sp->GetBytes() + data_offset;
return ELFHeader::MagicBytesMatch(magic);
}
return false;
}
/*
* crc function from http://svnweb.freebsd.org/base/head/sys/libkern/crc32.c
*
* COPYRIGHT (C) 1986 Gary S. Brown. You may use this program, or
* code or tables extracted from it, as desired without restriction.
*/
static uint32_t
calc_crc32(uint32_t crc, const void *buf, size_t size)
{
static const uint32_t g_crc32_tab[] =
{
0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2,
0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9,
0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c,
0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423,
0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106,
0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d,
0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7,
0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa,
0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81,
0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84,
0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e,
0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55,
0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28,
0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f,
0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69,
0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc,
0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693,
0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
};
const uint8_t *p = (const uint8_t *)buf;
crc = crc ^ ~0U;
while (size--)
crc = g_crc32_tab[(crc ^ *p++) & 0xFF] ^ (crc >> 8);
return crc ^ ~0U;
}
static uint32_t
calc_gnu_debuglink_crc32(const void *buf, size_t size)
{
return calc_crc32(0U, buf, size);
}
uint32_t
ObjectFileELF::CalculateELFNotesSegmentsCRC32 (const ProgramHeaderColl& program_headers,
DataExtractor& object_data)
{
typedef ProgramHeaderCollConstIter Iter;
uint32_t core_notes_crc = 0;
for (Iter I = program_headers.begin(); I != program_headers.end(); ++I)
{
if (I->p_type == llvm::ELF::PT_NOTE)
{
const elf_off ph_offset = I->p_offset;
const size_t ph_size = I->p_filesz;
DataExtractor segment_data;
if (segment_data.SetData(object_data, ph_offset, ph_size) != ph_size)
{
// The ELF program header contained incorrect data,
// probably corefile is incomplete or corrupted.
break;
}
core_notes_crc = calc_crc32(core_notes_crc,
segment_data.GetDataStart(),
segment_data.GetByteSize());
}
}
return core_notes_crc;
}
static const char*
OSABIAsCString (unsigned char osabi_byte)
{
#define _MAKE_OSABI_CASE(x) case x: return #x
switch (osabi_byte)
{
_MAKE_OSABI_CASE(ELFOSABI_NONE);
_MAKE_OSABI_CASE(ELFOSABI_HPUX);
_MAKE_OSABI_CASE(ELFOSABI_NETBSD);
_MAKE_OSABI_CASE(ELFOSABI_GNU);
_MAKE_OSABI_CASE(ELFOSABI_HURD);
_MAKE_OSABI_CASE(ELFOSABI_SOLARIS);
_MAKE_OSABI_CASE(ELFOSABI_AIX);
_MAKE_OSABI_CASE(ELFOSABI_IRIX);
_MAKE_OSABI_CASE(ELFOSABI_FREEBSD);
_MAKE_OSABI_CASE(ELFOSABI_TRU64);
_MAKE_OSABI_CASE(ELFOSABI_MODESTO);
_MAKE_OSABI_CASE(ELFOSABI_OPENBSD);
_MAKE_OSABI_CASE(ELFOSABI_OPENVMS);
_MAKE_OSABI_CASE(ELFOSABI_NSK);
_MAKE_OSABI_CASE(ELFOSABI_AROS);
_MAKE_OSABI_CASE(ELFOSABI_FENIXOS);
_MAKE_OSABI_CASE(ELFOSABI_C6000_ELFABI);
_MAKE_OSABI_CASE(ELFOSABI_C6000_LINUX);
_MAKE_OSABI_CASE(ELFOSABI_ARM);
_MAKE_OSABI_CASE(ELFOSABI_STANDALONE);
default:
return "<unknown-osabi>";
}
#undef _MAKE_OSABI_CASE
}
static bool
GetOsFromOSABI (unsigned char osabi_byte, llvm::Triple::OSType &ostype)
{
switch (osabi_byte)
{
case ELFOSABI_AIX: ostype = llvm::Triple::OSType::AIX; break;
case ELFOSABI_FREEBSD: ostype = llvm::Triple::OSType::FreeBSD; break;
case ELFOSABI_GNU: ostype = llvm::Triple::OSType::Linux; break;
case ELFOSABI_NETBSD: ostype = llvm::Triple::OSType::NetBSD; break;
case ELFOSABI_OPENBSD: ostype = llvm::Triple::OSType::OpenBSD; break;
case ELFOSABI_SOLARIS: ostype = llvm::Triple::OSType::Solaris; break;
default:
ostype = llvm::Triple::OSType::UnknownOS;
}
return ostype != llvm::Triple::OSType::UnknownOS;
}
size_t
ObjectFileELF::GetModuleSpecifications (const lldb_private::FileSpec& file,
lldb::DataBufferSP& data_sp,
lldb::offset_t data_offset,
lldb::offset_t file_offset,
lldb::offset_t length,
lldb_private::ModuleSpecList &specs)
{
Log *log(lldb_private::GetLogIfAllCategoriesSet (LIBLLDB_LOG_MODULES));
const size_t initial_count = specs.GetSize();
if (ObjectFileELF::MagicBytesMatch(data_sp, 0, data_sp->GetByteSize()))
{
DataExtractor data;
data.SetData(data_sp);
elf::ELFHeader header;
if (header.Parse(data, &data_offset))
{
if (data_sp)
{
ModuleSpec spec (file);
const uint32_t sub_type = subTypeFromElfHeader(header);
spec.GetArchitecture().SetArchitecture(eArchTypeELF,
header.e_machine,
sub_type);
if (spec.GetArchitecture().IsValid())
{
llvm::Triple::OSType ostype;
// First try to determine the OS type from the OSABI field in the elf header.
if (log)
log->Printf ("ObjectFileELF::%s file '%s' module OSABI: %s", __FUNCTION__, file.GetPath ().c_str (), OSABIAsCString (header.e_ident[EI_OSABI]));
if (GetOsFromOSABI (header.e_ident[EI_OSABI], ostype) && ostype != llvm::Triple::OSType::UnknownOS)
{
spec.GetArchitecture ().GetTriple ().setOS (ostype);
// Also clear the vendor so we don't end up with situations like
// x86_64-apple-FreeBSD.
spec.GetArchitecture ().GetTriple ().setVendor (llvm::Triple::VendorType::UnknownVendor);
if (log)
log->Printf ("ObjectFileELF::%s file '%s' set ELF module OS type from ELF header OSABI.", __FUNCTION__, file.GetPath ().c_str ());
}
// Try to get the UUID from the section list. Usually that's at the end, so
// map the file in if we don't have it already.
size_t section_header_end = header.e_shoff + header.e_shnum * header.e_shentsize;
if (section_header_end > data_sp->GetByteSize())
{
data_sp = file.MemoryMapFileContentsIfLocal (file_offset, section_header_end);
data.SetData(data_sp);
}
uint32_t gnu_debuglink_crc = 0;
std::string gnu_debuglink_file;
SectionHeaderColl section_headers;
lldb_private::UUID &uuid = spec.GetUUID();
GetSectionHeaderInfo(section_headers, data, header, uuid, gnu_debuglink_file, gnu_debuglink_crc, spec.GetArchitecture ());
// If the module vendor is not set and the module OS matches this host OS, set the module vendor to the host vendor.
llvm::Triple &spec_triple = spec.GetArchitecture ().GetTriple ();
if (spec_triple.getVendor () == llvm::Triple::VendorType::UnknownVendor)
{
const llvm::Triple &host_triple = HostInfo::GetArchitecture().GetTriple();
if (spec_triple.getOS () == host_triple.getOS ())
spec_triple.setVendor (host_triple.getVendor ());
}
if (log)
log->Printf ("ObjectFileELF::%s file '%s' module set to triple: %s (architecture %s)", __FUNCTION__, file.GetPath ().c_str (), spec_triple.getTriple ().c_str (), spec.GetArchitecture ().GetArchitectureName ());
if (!uuid.IsValid())
{
uint32_t core_notes_crc = 0;
if (!gnu_debuglink_crc)
{
lldb_private::Timer scoped_timer (__PRETTY_FUNCTION__,
"Calculating module crc32 %s with size %" PRIu64 " KiB",
file.GetLastPathComponent().AsCString(),
(file.GetByteSize()-file_offset)/1024);
// For core files - which usually don't happen to have a gnu_debuglink,
// and are pretty bulky - calculating whole contents crc32 would be too much of luxury.
// Thus we will need to fallback to something simpler.
if (header.e_type == llvm::ELF::ET_CORE)
{
size_t program_headers_end = header.e_phoff + header.e_phnum * header.e_phentsize;
if (program_headers_end > data_sp->GetByteSize())
{
data_sp = file.MemoryMapFileContentsIfLocal(file_offset, program_headers_end);
data.SetData(data_sp);
}
ProgramHeaderColl program_headers;
GetProgramHeaderInfo(program_headers, data, header);
size_t segment_data_end = 0;
for (ProgramHeaderCollConstIter I = program_headers.begin();
I != program_headers.end(); ++I)
{
segment_data_end = std::max<unsigned long long> (I->p_offset + I->p_filesz, segment_data_end);
}
if (segment_data_end > data_sp->GetByteSize())
{
data_sp = file.MemoryMapFileContentsIfLocal(file_offset, segment_data_end);
data.SetData(data_sp);
}
core_notes_crc = CalculateELFNotesSegmentsCRC32 (program_headers, data);
}
else
{
// Need to map entire file into memory to calculate the crc.
data_sp = file.MemoryMapFileContentsIfLocal (file_offset, SIZE_MAX);
data.SetData(data_sp);
gnu_debuglink_crc = calc_gnu_debuglink_crc32 (data.GetDataStart(), data.GetByteSize());
}
}
if (gnu_debuglink_crc)
{
// Use 4 bytes of crc from the .gnu_debuglink section.
uint32_t uuidt[4] = { gnu_debuglink_crc, 0, 0, 0 };
uuid.SetBytes (uuidt, sizeof(uuidt));
}
else if (core_notes_crc)
{
// Use 8 bytes - first 4 bytes for *magic* prefix, mainly to make it look different form
// .gnu_debuglink crc followed by 4 bytes of note segments crc.
uint32_t uuidt[4] = { g_core_uuid_magic, core_notes_crc, 0, 0 };
uuid.SetBytes (uuidt, sizeof(uuidt));
}
}
specs.Append(spec);
}
}
}
}
return specs.GetSize() - initial_count;
}
//------------------------------------------------------------------
// PluginInterface protocol
//------------------------------------------------------------------
lldb_private::ConstString
ObjectFileELF::GetPluginName()
{
return GetPluginNameStatic();
}
uint32_t
ObjectFileELF::GetPluginVersion()
{
return m_plugin_version;
}
//------------------------------------------------------------------
// ObjectFile protocol
//------------------------------------------------------------------
ObjectFileELF::ObjectFileELF (const lldb::ModuleSP &module_sp,
DataBufferSP& data_sp,
lldb::offset_t data_offset,
const FileSpec* file,
lldb::offset_t file_offset,
lldb::offset_t length) :
ObjectFile(module_sp, file, file_offset, length, data_sp, data_offset),
m_header(),
m_uuid(),
m_gnu_debuglink_file(),
m_gnu_debuglink_crc(0),
m_program_headers(),
m_section_headers(),
m_dynamic_symbols(),
m_filespec_ap(),
m_entry_point_address(),
m_arch_spec()
{
if (file)
m_file = *file;
::memset(&m_header, 0, sizeof(m_header));
}
ObjectFileELF::ObjectFileELF (const lldb::ModuleSP &module_sp,
DataBufferSP& data_sp,
const lldb::ProcessSP &process_sp,
addr_t header_addr) :
ObjectFile(module_sp, process_sp, LLDB_INVALID_ADDRESS, data_sp),
m_header(),
m_uuid(),
m_gnu_debuglink_file(),
m_gnu_debuglink_crc(0),
m_program_headers(),
m_section_headers(),
m_dynamic_symbols(),
m_filespec_ap(),
m_entry_point_address(),
m_arch_spec()
{
::memset(&m_header, 0, sizeof(m_header));
}
ObjectFileELF::~ObjectFileELF()
{
}
bool
ObjectFileELF::IsExecutable() const
{
return ((m_header.e_type & ET_EXEC) != 0) || (m_header.e_entry != 0);
}
bool
ObjectFileELF::SetLoadAddress (Target &target,
lldb::addr_t value,
bool value_is_offset)
{
ModuleSP module_sp = GetModule();
if (module_sp)
{
size_t num_loaded_sections = 0;
SectionList *section_list = GetSectionList ();
if (section_list)
{
if (value_is_offset)
{
const size_t num_sections = section_list->GetSize();
size_t sect_idx = 0;
for (sect_idx = 0; sect_idx < num_sections; ++sect_idx)
{
// Iterate through the object file sections to find all
// of the sections that have SHF_ALLOC in their flag bits.
SectionSP section_sp (section_list->GetSectionAtIndex (sect_idx));
// if (section_sp && !section_sp->IsThreadSpecific())
if (section_sp && section_sp->Test(SHF_ALLOC))
{
if (target.GetSectionLoadList().SetSectionLoadAddress (section_sp, section_sp->GetFileAddress() + value))
++num_loaded_sections;
}
}
return num_loaded_sections > 0;
}
else
{
// Not sure how to slide an ELF file given the base address
// of the ELF file in memory
}
}
}
return false; // If it changed
}
ByteOrder
ObjectFileELF::GetByteOrder() const
{
if (m_header.e_ident[EI_DATA] == ELFDATA2MSB)
return eByteOrderBig;
if (m_header.e_ident[EI_DATA] == ELFDATA2LSB)
return eByteOrderLittle;
return eByteOrderInvalid;
}
uint32_t
ObjectFileELF::GetAddressByteSize() const
{
return m_data.GetAddressByteSize();
}
// Top 16 bits of the `Symbol` flags are available.
#define ARM_ELF_SYM_IS_THUMB (1 << 16)
AddressClass
ObjectFileELF::GetAddressClass (addr_t file_addr)
{
auto res = ObjectFile::GetAddressClass (file_addr);
if (res != eAddressClassCode)
return res;
ArchSpec arch_spec;
GetArchitecture(arch_spec);
if (arch_spec.GetMachine() != llvm::Triple::arm)
return res;
auto symtab = GetSymtab();
if (symtab == nullptr)
return res;
auto symbol = symtab->FindSymbolContainingFileAddress(file_addr);
if (symbol == nullptr)
return res;
// Thumb symbols have the lower bit set in the flags field so we just check
// for that.
if (symbol->GetFlags() & ARM_ELF_SYM_IS_THUMB)
res = eAddressClassCodeAlternateISA;
return res;
}
size_t
ObjectFileELF::SectionIndex(const SectionHeaderCollIter &I)
{
return std::distance(m_section_headers.begin(), I) + 1u;
}
size_t
ObjectFileELF::SectionIndex(const SectionHeaderCollConstIter &I) const
{
return std::distance(m_section_headers.begin(), I) + 1u;
}
bool
ObjectFileELF::ParseHeader()
{
lldb::offset_t offset = 0;
return m_header.Parse(m_data, &offset);
}
bool
ObjectFileELF::GetUUID(lldb_private::UUID* uuid)
{
// Need to parse the section list to get the UUIDs, so make sure that's been done.
if (!ParseSectionHeaders() && GetType() != ObjectFile::eTypeCoreFile)
return false;
if (m_uuid.IsValid())
{
// We have the full build id uuid.
*uuid = m_uuid;
return true;
}
else if (GetType() == ObjectFile::eTypeCoreFile)
{
uint32_t core_notes_crc = 0;
if (!ParseProgramHeaders())
return false;
core_notes_crc = CalculateELFNotesSegmentsCRC32(m_program_headers, m_data);
if (core_notes_crc)
{
// Use 8 bytes - first 4 bytes for *magic* prefix, mainly to make it
// look different form .gnu_debuglink crc - followed by 4 bytes of note
// segments crc.
uint32_t uuidt[4] = { g_core_uuid_magic, core_notes_crc, 0, 0 };
m_uuid.SetBytes (uuidt, sizeof(uuidt));
}
}
else
{
if (!m_gnu_debuglink_crc)
m_gnu_debuglink_crc = calc_gnu_debuglink_crc32 (m_data.GetDataStart(), m_data.GetByteSize());
if (m_gnu_debuglink_crc)
{
// Use 4 bytes of crc from the .gnu_debuglink section.
uint32_t uuidt[4] = { m_gnu_debuglink_crc, 0, 0, 0 };
m_uuid.SetBytes (uuidt, sizeof(uuidt));
}
}
if (m_uuid.IsValid())
{
*uuid = m_uuid;
return true;
}
return false;
}
lldb_private::FileSpecList
ObjectFileELF::GetDebugSymbolFilePaths()
{
FileSpecList file_spec_list;
if (!m_gnu_debuglink_file.empty())
{
FileSpec file_spec (m_gnu_debuglink_file.c_str(), false);
file_spec_list.Append (file_spec);
}
return file_spec_list;