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//===-- DynamicLoaderPOSIXDYLD.cpp ----------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// Main header include
#include "DynamicLoaderPOSIXDYLD.h"
#include "lldb/Breakpoint/BreakpointLocation.h"
#include "lldb/Core/Module.h"
#include "lldb/Core/ModuleSpec.h"
#include "lldb/Core/PluginManager.h"
#include "lldb/Core/Section.h"
#include "lldb/Symbol/Function.h"
#include "lldb/Symbol/ObjectFile.h"
#include "lldb/Target/MemoryRegionInfo.h"
#include "lldb/Target/Platform.h"
#include "lldb/Target/Target.h"
#include "lldb/Target/Thread.h"
#include "lldb/Target/ThreadPlanRunToAddress.h"
#include "lldb/Utility/Log.h"
#include "lldb/Utility/ProcessInfo.h"
#include <memory>
using namespace lldb;
using namespace lldb_private;
LLDB_PLUGIN_DEFINE_ADV(DynamicLoaderPOSIXDYLD, DynamicLoaderPosixDYLD)
void DynamicLoaderPOSIXDYLD::Initialize() {
PluginManager::RegisterPlugin(GetPluginNameStatic(),
GetPluginDescriptionStatic(), CreateInstance);
}
void DynamicLoaderPOSIXDYLD::Terminate() {}
lldb_private::ConstString DynamicLoaderPOSIXDYLD::GetPluginName() {
return GetPluginNameStatic();
}
lldb_private::ConstString DynamicLoaderPOSIXDYLD::GetPluginNameStatic() {
static ConstString g_name("linux-dyld");
return g_name;
}
const char *DynamicLoaderPOSIXDYLD::GetPluginDescriptionStatic() {
return "Dynamic loader plug-in that watches for shared library "
"loads/unloads in POSIX processes.";
}
uint32_t DynamicLoaderPOSIXDYLD::GetPluginVersion() { return 1; }
DynamicLoader *DynamicLoaderPOSIXDYLD::CreateInstance(Process *process,
bool force) {
bool create = force;
if (!create) {
const llvm::Triple &triple_ref =
process->GetTarget().GetArchitecture().GetTriple();
if (triple_ref.getOS() == llvm::Triple::FreeBSD ||
triple_ref.getOS() == llvm::Triple::Linux ||
triple_ref.getOS() == llvm::Triple::NetBSD)
create = true;
}
if (create)
return new DynamicLoaderPOSIXDYLD(process);
return nullptr;
}
DynamicLoaderPOSIXDYLD::DynamicLoaderPOSIXDYLD(Process *process)
: DynamicLoader(process), m_rendezvous(process),
m_load_offset(LLDB_INVALID_ADDRESS), m_entry_point(LLDB_INVALID_ADDRESS),
m_auxv(), m_dyld_bid(LLDB_INVALID_BREAK_ID),
m_vdso_base(LLDB_INVALID_ADDRESS),
m_interpreter_base(LLDB_INVALID_ADDRESS) {}
DynamicLoaderPOSIXDYLD::~DynamicLoaderPOSIXDYLD() {
if (m_dyld_bid != LLDB_INVALID_BREAK_ID) {
m_process->GetTarget().RemoveBreakpointByID(m_dyld_bid);
m_dyld_bid = LLDB_INVALID_BREAK_ID;
}
}
void DynamicLoaderPOSIXDYLD::DidAttach() {
Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER));
LLDB_LOGF(log, "DynamicLoaderPOSIXDYLD::%s() pid %" PRIu64, __FUNCTION__,
m_process ? m_process->GetID() : LLDB_INVALID_PROCESS_ID);
m_auxv = std::make_unique<AuxVector>(m_process->GetAuxvData());
LLDB_LOGF(
log, "DynamicLoaderPOSIXDYLD::%s pid %" PRIu64 " reloaded auxv data",
__FUNCTION__, m_process ? m_process->GetID() : LLDB_INVALID_PROCESS_ID);
// ask the process if it can load any of its own modules
auto error = m_process->LoadModules();
LLDB_LOG_ERROR(log, std::move(error), "Couldn't load modules: {0}");
ModuleSP executable_sp = GetTargetExecutable();
ResolveExecutableModule(executable_sp);
// find the main process load offset
addr_t load_offset = ComputeLoadOffset();
LLDB_LOGF(log,
"DynamicLoaderPOSIXDYLD::%s pid %" PRIu64
" executable '%s', load_offset 0x%" PRIx64,
__FUNCTION__,
m_process ? m_process->GetID() : LLDB_INVALID_PROCESS_ID,
executable_sp ? executable_sp->GetFileSpec().GetPath().c_str()
: "<null executable>",
load_offset);
EvalSpecialModulesStatus();
// if we dont have a load address we cant re-base
bool rebase_exec = load_offset != LLDB_INVALID_ADDRESS;
// if we have a valid executable
if (executable_sp.get()) {
lldb_private::ObjectFile *obj = executable_sp->GetObjectFile();
if (obj) {
// don't rebase if the module already has a load address
Target &target = m_process->GetTarget();
Address addr = obj->GetImageInfoAddress(&target);
if (addr.GetLoadAddress(&target) != LLDB_INVALID_ADDRESS)
rebase_exec = false;
}
} else {
// no executable, nothing to re-base
rebase_exec = false;
}
// if the target executable should be re-based
if (rebase_exec) {
ModuleList module_list;
module_list.Append(executable_sp);
LLDB_LOGF(log,
"DynamicLoaderPOSIXDYLD::%s pid %" PRIu64
" added executable '%s' to module load list",
__FUNCTION__,
m_process ? m_process->GetID() : LLDB_INVALID_PROCESS_ID,
executable_sp->GetFileSpec().GetPath().c_str());
UpdateLoadedSections(executable_sp, LLDB_INVALID_ADDRESS, load_offset,
true);
LoadAllCurrentModules();
m_process->GetTarget().ModulesDidLoad(module_list);
if (log) {
LLDB_LOGF(log,
"DynamicLoaderPOSIXDYLD::%s told the target about the "
"modules that loaded:",
__FUNCTION__);
for (auto module_sp : module_list.Modules()) {
LLDB_LOGF(log, "-- [module] %s (pid %" PRIu64 ")",
module_sp ? module_sp->GetFileSpec().GetPath().c_str()
: "<null>",
m_process ? m_process->GetID() : LLDB_INVALID_PROCESS_ID);
}
}
}
if (executable_sp.get()) {
if (!SetRendezvousBreakpoint()) {
// If we cannot establish rendezvous breakpoint right now we'll try again
// at entry point.
ProbeEntry();
}
}
}
void DynamicLoaderPOSIXDYLD::DidLaunch() {
Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER));
LLDB_LOGF(log, "DynamicLoaderPOSIXDYLD::%s()", __FUNCTION__);
ModuleSP executable;
addr_t load_offset;
m_auxv = std::make_unique<AuxVector>(m_process->GetAuxvData());
executable = GetTargetExecutable();
load_offset = ComputeLoadOffset();
EvalSpecialModulesStatus();
if (executable.get() && load_offset != LLDB_INVALID_ADDRESS) {
ModuleList module_list;
module_list.Append(executable);
UpdateLoadedSections(executable, LLDB_INVALID_ADDRESS, load_offset, true);
LLDB_LOGF(log, "DynamicLoaderPOSIXDYLD::%s about to call ProbeEntry()",
__FUNCTION__);
if (!SetRendezvousBreakpoint()) {
// If we cannot establish rendezvous breakpoint right now we'll try again
// at entry point.
ProbeEntry();
}
LoadVDSO();
m_process->GetTarget().ModulesDidLoad(module_list);
}
}
Status DynamicLoaderPOSIXDYLD::CanLoadImage() { return Status(); }
void DynamicLoaderPOSIXDYLD::UpdateLoadedSections(ModuleSP module,
addr_t link_map_addr,
addr_t base_addr,
bool base_addr_is_offset) {
m_loaded_modules[module] = link_map_addr;
UpdateLoadedSectionsCommon(module, base_addr, base_addr_is_offset);
}
void DynamicLoaderPOSIXDYLD::UnloadSections(const ModuleSP module) {
m_loaded_modules.erase(module);
UnloadSectionsCommon(module);
}
void DynamicLoaderPOSIXDYLD::ProbeEntry() {
Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER));
const addr_t entry = GetEntryPoint();
if (entry == LLDB_INVALID_ADDRESS) {
LLDB_LOGF(
log,
"DynamicLoaderPOSIXDYLD::%s pid %" PRIu64
" GetEntryPoint() returned no address, not setting entry breakpoint",
__FUNCTION__, m_process ? m_process->GetID() : LLDB_INVALID_PROCESS_ID);
return;
}
LLDB_LOGF(log,
"DynamicLoaderPOSIXDYLD::%s pid %" PRIu64
" GetEntryPoint() returned address 0x%" PRIx64
", setting entry breakpoint",
__FUNCTION__,
m_process ? m_process->GetID() : LLDB_INVALID_PROCESS_ID, entry);
if (m_process) {
Breakpoint *const entry_break =
m_process->GetTarget().CreateBreakpoint(entry, true, false).get();
entry_break->SetCallback(EntryBreakpointHit, this, true);
entry_break->SetBreakpointKind("shared-library-event");
// Shoudn't hit this more than once.
entry_break->SetOneShot(true);
}
}
// The runtime linker has run and initialized the rendezvous structure once the
// process has hit its entry point. When we hit the corresponding breakpoint
// we interrogate the rendezvous structure to get the load addresses of all
// dependent modules for the process. Similarly, we can discover the runtime
// linker function and setup a breakpoint to notify us of any dynamically
// loaded modules (via dlopen).
bool DynamicLoaderPOSIXDYLD::EntryBreakpointHit(
void *baton, StoppointCallbackContext *context, user_id_t break_id,
user_id_t break_loc_id) {
assert(baton && "null baton");
if (!baton)
return false;
Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER));
DynamicLoaderPOSIXDYLD *const dyld_instance =
static_cast<DynamicLoaderPOSIXDYLD *>(baton);
LLDB_LOGF(log, "DynamicLoaderPOSIXDYLD::%s called for pid %" PRIu64,
__FUNCTION__,
dyld_instance->m_process ? dyld_instance->m_process->GetID()
: LLDB_INVALID_PROCESS_ID);
// Disable the breakpoint --- if a stop happens right after this, which we've
// seen on occasion, we don't want the breakpoint stepping thread-plan logic
// to show a breakpoint instruction at the disassembled entry point to the
// program. Disabling it prevents it. (One-shot is not enough - one-shot
// removal logic only happens after the breakpoint goes public, which wasn't
// happening in our scenario).
if (dyld_instance->m_process) {
BreakpointSP breakpoint_sp =
dyld_instance->m_process->GetTarget().GetBreakpointByID(break_id);
if (breakpoint_sp) {
LLDB_LOGF(log,
"DynamicLoaderPOSIXDYLD::%s pid %" PRIu64
" disabling breakpoint id %" PRIu64,
__FUNCTION__, dyld_instance->m_process->GetID(), break_id);
breakpoint_sp->SetEnabled(false);
} else {
LLDB_LOGF(log,
"DynamicLoaderPOSIXDYLD::%s pid %" PRIu64
" failed to find breakpoint for breakpoint id %" PRIu64,
__FUNCTION__, dyld_instance->m_process->GetID(), break_id);
}
} else {
LLDB_LOGF(log,
"DynamicLoaderPOSIXDYLD::%s breakpoint id %" PRIu64
" no Process instance! Cannot disable breakpoint",
__FUNCTION__, break_id);
}
dyld_instance->LoadAllCurrentModules();
dyld_instance->SetRendezvousBreakpoint();
return false; // Continue running.
}
bool DynamicLoaderPOSIXDYLD::SetRendezvousBreakpoint() {
Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER));
if (m_dyld_bid != LLDB_INVALID_BREAK_ID) {
LLDB_LOG(log,
"Rendezvous breakpoint breakpoint id {0} for pid {1}"
"is already set.",
m_dyld_bid,
m_process ? m_process->GetID() : LLDB_INVALID_PROCESS_ID);
return true;
}
addr_t break_addr;
Target &target = m_process->GetTarget();
BreakpointSP dyld_break;
if (m_rendezvous.IsValid()) {
break_addr = m_rendezvous.GetBreakAddress();
LLDB_LOG(log, "Setting rendezvous break address for pid {0} at {1:x}",
m_process ? m_process->GetID() : LLDB_INVALID_PROCESS_ID,
break_addr);
dyld_break = target.CreateBreakpoint(break_addr, true, false);
} else {
LLDB_LOG(log, "Rendezvous structure is not set up yet. "
"Trying to locate rendezvous breakpoint in the interpreter "
"by symbol name.");
ModuleSP interpreter = LoadInterpreterModule();
if (!interpreter) {
LLDB_LOG(log, "Can't find interpreter, rendezvous breakpoint isn't set.");
return false;
}
// Function names from different dynamic loaders that are known to be used
// as rendezvous between the loader and debuggers.
static std::vector<std::string> DebugStateCandidates{
"_dl_debug_state", "rtld_db_dlactivity", "__dl_rtld_db_dlactivity",
"r_debug_state", "_r_debug_state", "_rtld_debug_state",
};
FileSpecList containingModules;
containingModules.Append(interpreter->GetFileSpec());
dyld_break = target.CreateBreakpoint(
&containingModules, nullptr /* containingSourceFiles */,
DebugStateCandidates, eFunctionNameTypeFull, eLanguageTypeC,
0, /* offset */
eLazyBoolNo, /* skip_prologue */
true, /* internal */
false /* request_hardware */);
}
if (dyld_break->GetNumResolvedLocations() != 1) {
LLDB_LOG(
log,
"Rendezvous breakpoint has abnormal number of"
" resolved locations ({0}) in pid {1}. It's supposed to be exactly 1.",
dyld_break->GetNumResolvedLocations(),
m_process ? m_process->GetID() : LLDB_INVALID_PROCESS_ID);
target.RemoveBreakpointByID(dyld_break->GetID());
return false;
}
BreakpointLocationSP location = dyld_break->GetLocationAtIndex(0);
LLDB_LOG(log,
"Successfully set rendezvous breakpoint at address {0:x} "
"for pid {1}",
location->GetLoadAddress(),
m_process ? m_process->GetID() : LLDB_INVALID_PROCESS_ID);
dyld_break->SetCallback(RendezvousBreakpointHit, this, true);
dyld_break->SetBreakpointKind("shared-library-event");
m_dyld_bid = dyld_break->GetID();
return true;
}
bool DynamicLoaderPOSIXDYLD::RendezvousBreakpointHit(
void *baton, StoppointCallbackContext *context, user_id_t break_id,
user_id_t break_loc_id) {
assert(baton && "null baton");
if (!baton)
return false;
Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER));
DynamicLoaderPOSIXDYLD *const dyld_instance =
static_cast<DynamicLoaderPOSIXDYLD *>(baton);
LLDB_LOGF(log, "DynamicLoaderPOSIXDYLD::%s called for pid %" PRIu64,
__FUNCTION__,
dyld_instance->m_process ? dyld_instance->m_process->GetID()
: LLDB_INVALID_PROCESS_ID);
dyld_instance->RefreshModules();
// Return true to stop the target, false to just let the target run.
const bool stop_when_images_change = dyld_instance->GetStopWhenImagesChange();
LLDB_LOGF(log,
"DynamicLoaderPOSIXDYLD::%s pid %" PRIu64
" stop_when_images_change=%s",
__FUNCTION__,
dyld_instance->m_process ? dyld_instance->m_process->GetID()
: LLDB_INVALID_PROCESS_ID,
stop_when_images_change ? "true" : "false");
return stop_when_images_change;
}
void DynamicLoaderPOSIXDYLD::RefreshModules() {
if (!m_rendezvous.Resolve())
return;
DYLDRendezvous::iterator I;
DYLDRendezvous::iterator E;
ModuleList &loaded_modules = m_process->GetTarget().GetImages();
if (m_rendezvous.ModulesDidLoad()) {
ModuleList new_modules;
E = m_rendezvous.loaded_end();
for (I = m_rendezvous.loaded_begin(); I != E; ++I) {
ModuleSP module_sp =
LoadModuleAtAddress(I->file_spec, I->link_addr, I->base_addr, true);
if (module_sp.get()) {
loaded_modules.AppendIfNeeded(module_sp);
new_modules.Append(module_sp);
}
}
m_process->GetTarget().ModulesDidLoad(new_modules);
}
if (m_rendezvous.ModulesDidUnload()) {
ModuleList old_modules;
E = m_rendezvous.unloaded_end();
for (I = m_rendezvous.unloaded_begin(); I != E; ++I) {
ModuleSpec module_spec{I->file_spec};
ModuleSP module_sp = loaded_modules.FindFirstModule(module_spec);
if (module_sp.get()) {
old_modules.Append(module_sp);
UnloadSections(module_sp);
}
}
loaded_modules.Remove(old_modules);
m_process->GetTarget().ModulesDidUnload(old_modules, false);
}
}
ThreadPlanSP
DynamicLoaderPOSIXDYLD::GetStepThroughTrampolinePlan(Thread &thread,
bool stop) {
ThreadPlanSP thread_plan_sp;
StackFrame *frame = thread.GetStackFrameAtIndex(0).get();
const SymbolContext &context = frame->GetSymbolContext(eSymbolContextSymbol);
Symbol *sym = context.symbol;
if (sym == nullptr || !sym->IsTrampoline())
return thread_plan_sp;
ConstString sym_name = sym->GetName();
if (!sym_name)
return thread_plan_sp;
SymbolContextList target_symbols;
Target &target = thread.GetProcess()->GetTarget();
const ModuleList &images = target.GetImages();
images.FindSymbolsWithNameAndType(sym_name, eSymbolTypeCode, target_symbols);
size_t num_targets = target_symbols.GetSize();
if (!num_targets)
return thread_plan_sp;
typedef std::vector<lldb::addr_t> AddressVector;
AddressVector addrs;
for (size_t i = 0; i < num_targets; ++i) {
SymbolContext context;
AddressRange range;
if (target_symbols.GetContextAtIndex(i, context)) {
context.GetAddressRange(eSymbolContextEverything, 0, false, range);
lldb::addr_t addr = range.GetBaseAddress().GetLoadAddress(&target);
if (addr != LLDB_INVALID_ADDRESS)
addrs.push_back(addr);
}
}
if (addrs.size() > 0) {
AddressVector::iterator start = addrs.begin();
AddressVector::iterator end = addrs.end();
llvm::sort(start, end);
addrs.erase(std::unique(start, end), end);
thread_plan_sp =
std::make_shared<ThreadPlanRunToAddress>(thread, addrs, stop);
}
return thread_plan_sp;
}
void DynamicLoaderPOSIXDYLD::LoadVDSO() {
if (m_vdso_base == LLDB_INVALID_ADDRESS)
return;
FileSpec file("[vdso]");
MemoryRegionInfo info;
Status status = m_process->GetMemoryRegionInfo(m_vdso_base, info);
if (status.Fail()) {
Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER));
LLDB_LOG(log, "Failed to get vdso region info: {0}", status);
return;
}
if (ModuleSP module_sp = m_process->ReadModuleFromMemory(
file, m_vdso_base, info.GetRange().GetByteSize())) {
UpdateLoadedSections(module_sp, LLDB_INVALID_ADDRESS, m_vdso_base, false);
m_process->GetTarget().GetImages().AppendIfNeeded(module_sp);
}
}
ModuleSP DynamicLoaderPOSIXDYLD::LoadInterpreterModule() {
if (m_interpreter_base == LLDB_INVALID_ADDRESS)
return nullptr;
MemoryRegionInfo info;
Target &target = m_process->GetTarget();
Status status = m_process->GetMemoryRegionInfo(m_interpreter_base, info);
if (status.Fail() || info.GetMapped() != MemoryRegionInfo::eYes ||
info.GetName().IsEmpty()) {
Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER));
LLDB_LOG(log, "Failed to get interpreter region info: {0}", status);
return nullptr;
}
FileSpec file(info.GetName().GetCString());
ModuleSpec module_spec(file, target.GetArchitecture());
if (ModuleSP module_sp = target.GetOrCreateModule(module_spec,
true /* notify */)) {
UpdateLoadedSections(module_sp, LLDB_INVALID_ADDRESS, m_interpreter_base,
false);
return module_sp;
}
return nullptr;
}
void DynamicLoaderPOSIXDYLD::LoadAllCurrentModules() {
DYLDRendezvous::iterator I;
DYLDRendezvous::iterator E;
ModuleList module_list;
Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER));
LoadVDSO();
if (!m_rendezvous.Resolve()) {
LLDB_LOGF(log,
"DynamicLoaderPOSIXDYLD::%s unable to resolve POSIX DYLD "
"rendezvous address",
__FUNCTION__);
return;
}
// The rendezvous class doesn't enumerate the main module, so track that
// ourselves here.
ModuleSP executable = GetTargetExecutable();
m_loaded_modules[executable] = m_rendezvous.GetLinkMapAddress();
std::vector<FileSpec> module_names;
for (I = m_rendezvous.begin(), E = m_rendezvous.end(); I != E; ++I)
module_names.push_back(I->file_spec);
m_process->PrefetchModuleSpecs(
module_names, m_process->GetTarget().GetArchitecture().GetTriple());
for (I = m_rendezvous.begin(), E = m_rendezvous.end(); I != E; ++I) {
ModuleSP module_sp =
LoadModuleAtAddress(I->file_spec, I->link_addr, I->base_addr, true);
if (module_sp.get()) {
LLDB_LOG(log, "LoadAllCurrentModules loading module: {0}",
I->file_spec.GetFilename());
module_list.Append(module_sp);
} else {
Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER));
LLDB_LOGF(
log,
"DynamicLoaderPOSIXDYLD::%s failed loading module %s at 0x%" PRIx64,
__FUNCTION__, I->file_spec.GetCString(), I->base_addr);
}
}
m_process->GetTarget().ModulesDidLoad(module_list);
}
addr_t DynamicLoaderPOSIXDYLD::ComputeLoadOffset() {
addr_t virt_entry;
if (m_load_offset != LLDB_INVALID_ADDRESS)
return m_load_offset;
if ((virt_entry = GetEntryPoint()) == LLDB_INVALID_ADDRESS)
return LLDB_INVALID_ADDRESS;
ModuleSP module = m_process->GetTarget().GetExecutableModule();
if (!module)
return LLDB_INVALID_ADDRESS;
ObjectFile *exe = module->GetObjectFile();
if (!exe)
return LLDB_INVALID_ADDRESS;
Address file_entry = exe->GetEntryPointAddress();
if (!file_entry.IsValid())
return LLDB_INVALID_ADDRESS;
m_load_offset = virt_entry - file_entry.GetFileAddress();
return m_load_offset;
}
void DynamicLoaderPOSIXDYLD::EvalSpecialModulesStatus() {
if (llvm::Optional<uint64_t> vdso_base =
m_auxv->GetAuxValue(AuxVector::AUXV_AT_SYSINFO_EHDR))
m_vdso_base = *vdso_base;
if (llvm::Optional<uint64_t> interpreter_base =
m_auxv->GetAuxValue(AuxVector::AUXV_AT_BASE))
m_interpreter_base = *interpreter_base;
}
addr_t DynamicLoaderPOSIXDYLD::GetEntryPoint() {
if (m_entry_point != LLDB_INVALID_ADDRESS)
return m_entry_point;
if (m_auxv == nullptr)
return LLDB_INVALID_ADDRESS;
llvm::Optional<uint64_t> entry_point =
m_auxv->GetAuxValue(AuxVector::AUXV_AT_ENTRY);
if (!entry_point)
return LLDB_INVALID_ADDRESS;
m_entry_point = static_cast<addr_t>(*entry_point);
const ArchSpec &arch = m_process->GetTarget().GetArchitecture();
// On ppc64, the entry point is actually a descriptor. Dereference it.
if (arch.GetMachine() == llvm::Triple::ppc64)
m_entry_point = ReadUnsignedIntWithSizeInBytes(m_entry_point, 8);
return m_entry_point;
}
lldb::addr_t
DynamicLoaderPOSIXDYLD::GetThreadLocalData(const lldb::ModuleSP module_sp,
const lldb::ThreadSP thread,
lldb::addr_t tls_file_addr) {
auto it = m_loaded_modules.find(module_sp);
if (it == m_loaded_modules.end())
return LLDB_INVALID_ADDRESS;
addr_t link_map = it->second;
if (link_map == LLDB_INVALID_ADDRESS)
return LLDB_INVALID_ADDRESS;
const DYLDRendezvous::ThreadInfo &metadata = m_rendezvous.GetThreadInfo();
if (!metadata.valid)
return LLDB_INVALID_ADDRESS;
// Get the thread pointer.
addr_t tp = thread->GetThreadPointer();
if (tp == LLDB_INVALID_ADDRESS)
return LLDB_INVALID_ADDRESS;
// Find the module's modid.
int modid_size = 4; // FIXME(spucci): This isn't right for big-endian 64-bit
int64_t modid = ReadUnsignedIntWithSizeInBytes(
link_map + metadata.modid_offset, modid_size);
if (modid == -1)
return LLDB_INVALID_ADDRESS;
// Lookup the DTV structure for this thread.
addr_t dtv_ptr = tp + metadata.dtv_offset;
addr_t dtv = ReadPointer(dtv_ptr);
if (dtv == LLDB_INVALID_ADDRESS)
return LLDB_INVALID_ADDRESS;
// Find the TLS block for this module.
addr_t dtv_slot = dtv + metadata.dtv_slot_size * modid;
addr_t tls_block = ReadPointer(dtv_slot + metadata.tls_offset);
Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER));
LLDB_LOGF(log,
"DynamicLoaderPOSIXDYLD::Performed TLS lookup: "
"module=%s, link_map=0x%" PRIx64 ", tp=0x%" PRIx64
", modid=%" PRId64 ", tls_block=0x%" PRIx64 "\n",
module_sp->GetObjectName().AsCString(""), link_map, tp,
(int64_t)modid, tls_block);
if (tls_block == LLDB_INVALID_ADDRESS)
return LLDB_INVALID_ADDRESS;
else
return tls_block + tls_file_addr;
}
void DynamicLoaderPOSIXDYLD::ResolveExecutableModule(
lldb::ModuleSP &module_sp) {
Log *log(GetLogIfAnyCategoriesSet(LIBLLDB_LOG_DYNAMIC_LOADER));
if (m_process == nullptr)
return;
auto &target = m_process->GetTarget();
const auto platform_sp = target.GetPlatform();
ProcessInstanceInfo process_info;
if (!m_process->GetProcessInfo(process_info)) {
LLDB_LOGF(log,
"DynamicLoaderPOSIXDYLD::%s - failed to get process info for "
"pid %" PRIu64,
__FUNCTION__, m_process->GetID());
return;
}
LLDB_LOGF(
log, "DynamicLoaderPOSIXDYLD::%s - got executable by pid %" PRIu64 ": %s",
__FUNCTION__, m_process->GetID(),
process_info.GetExecutableFile().GetPath().c_str());
ModuleSpec module_spec(process_info.GetExecutableFile(),
process_info.GetArchitecture());
if (module_sp && module_sp->MatchesModuleSpec(module_spec))
return;
const auto executable_search_paths(Target::GetDefaultExecutableSearchPaths());
auto error = platform_sp->ResolveExecutable(
module_spec, module_sp,
!executable_search_paths.IsEmpty() ? &executable_search_paths : nullptr);
if (error.Fail()) {
StreamString stream;
module_spec.Dump(stream);
LLDB_LOGF(log,
"DynamicLoaderPOSIXDYLD::%s - failed to resolve executable "
"with module spec \"%s\": %s",
__FUNCTION__, stream.GetData(), error.AsCString());
return;
}
target.SetExecutableModule(module_sp, eLoadDependentsNo);
}
bool DynamicLoaderPOSIXDYLD::AlwaysRelyOnEHUnwindInfo(
lldb_private::SymbolContext &sym_ctx) {
ModuleSP module_sp;
if (sym_ctx.symbol)
module_sp = sym_ctx.symbol->GetAddressRef().GetModule();
if (!module_sp && sym_ctx.function)
module_sp =
sym_ctx.function->GetAddressRange().GetBaseAddress().GetModule();
if (!module_sp)
return false;
return module_sp->GetFileSpec().GetPath() == "[vdso]";
}