Files
clang-p2996/lldb/source/Plugins/Process/scripted/ScriptedProcess.cpp
Med Ismail Bennani 312b43da05 [lldb/Plugins] Add ScriptedProcess Process Plugin
This patch introduces Scripted Processes to lldb.

The goal, here, is to be able to attach in the debugger to fake processes
that are backed by script files (in Python, Lua, Swift, etc ...) and
inspect them statically.

Scripted Processes can be used in cooperative multithreading environments
like the XNU Kernel or other real-time operating systems, but it can
also help us improve the debugger testing infrastructure by writting
synthetic tests that simulates hard-to-reproduce process/thread states.

Although ScriptedProcess is not feature-complete at the moment, it has
basic execution capabilities and will improve in the following patches.

rdar://65508855

Differential Revision: https://reviews.llvm.org/D100384

Signed-off-by: Med Ismail Bennani <medismail.bennani@gmail.com>
2021-07-22 14:47:33 +02:00

314 lines
9.7 KiB
C++

//===-- ScriptedProcess.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
//
//===----------------------------------------------------------------------===//
#include "ScriptedProcess.h"
#include "lldb/Core/Debugger.h"
#include "lldb/Core/Module.h"
#include "lldb/Core/PluginManager.h"
#include "lldb/Host/OptionParser.h"
#include "lldb/Host/ThreadLauncher.h"
#include "lldb/Interpreter/CommandInterpreter.h"
#include "lldb/Interpreter/OptionArgParser.h"
#include "lldb/Interpreter/OptionGroupBoolean.h"
#include "lldb/Interpreter/ScriptInterpreter.h"
#include "lldb/Target/MemoryRegionInfo.h"
#include "lldb/Target/RegisterContext.h"
#include "lldb/Utility/Log.h"
#include "lldb/Utility/Logging.h"
#include "lldb/Utility/State.h"
#include <mutex>
LLDB_PLUGIN_DEFINE(ScriptedProcess)
using namespace lldb;
using namespace lldb_private;
ConstString ScriptedProcess::GetPluginNameStatic() {
static ConstString g_name("ScriptedProcess");
return g_name;
}
const char *ScriptedProcess::GetPluginDescriptionStatic() {
return "Scripted Process plug-in.";
}
static constexpr lldb::ScriptLanguage g_supported_script_languages[] = {
ScriptLanguage::eScriptLanguagePython,
};
bool ScriptedProcess::IsScriptLanguageSupported(lldb::ScriptLanguage language) {
llvm::ArrayRef<lldb::ScriptLanguage> supported_languages =
llvm::makeArrayRef(g_supported_script_languages);
return llvm::is_contained(supported_languages, language);
}
void ScriptedProcess::CheckInterpreterAndScriptObject() const {
lldbassert(m_interpreter && "Invalid Script Interpreter.");
lldbassert(m_script_object_sp && "Invalid Script Object.");
}
lldb::ProcessSP ScriptedProcess::CreateInstance(lldb::TargetSP target_sp,
lldb::ListenerSP listener_sp,
const FileSpec *file,
bool can_connect) {
if (!target_sp ||
!IsScriptLanguageSupported(target_sp->GetDebugger().GetScriptLanguage()))
return nullptr;
Status error;
ScriptedProcess::ScriptedProcessInfo scripted_process_info(
target_sp->GetProcessLaunchInfo());
auto process_sp = std::make_shared<ScriptedProcess>(
target_sp, listener_sp, scripted_process_info, error);
if (error.Fail() || !process_sp || !process_sp->m_script_object_sp ||
!process_sp->m_script_object_sp->IsValid()) {
LLDB_LOGF(GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS), "%s",
error.AsCString());
return nullptr;
}
return process_sp;
}
bool ScriptedProcess::CanDebug(lldb::TargetSP target_sp,
bool plugin_specified_by_name) {
return true;
}
ScriptedProcess::ScriptedProcess(
lldb::TargetSP target_sp, lldb::ListenerSP listener_sp,
const ScriptedProcess::ScriptedProcessInfo &scripted_process_info,
Status &error)
: Process(target_sp, listener_sp),
m_scripted_process_info(scripted_process_info) {
if (!target_sp) {
error.SetErrorStringWithFormat("ScriptedProcess::%s () - ERROR: %s",
__FUNCTION__, "Invalid target");
return;
}
m_interpreter = target_sp->GetDebugger().GetScriptInterpreter();
if (!m_interpreter) {
error.SetErrorStringWithFormat("ScriptedProcess::%s () - ERROR: %s",
__FUNCTION__,
"Debugger has no Script Interpreter");
return;
}
StructuredData::ObjectSP object_sp = GetInterface().CreatePluginObject(
m_scripted_process_info.GetClassName().c_str(), target_sp,
m_scripted_process_info.GetDictionarySP());
if (!object_sp || !object_sp->IsValid()) {
error.SetErrorStringWithFormat("ScriptedProcess::%s () - ERROR: %s",
__FUNCTION__,
"Failed to create valid script object");
return;
}
m_script_object_sp = object_sp;
}
ScriptedProcess::~ScriptedProcess() {
Clear();
// We need to call finalize on the process before destroying ourselves to
// make sure all of the broadcaster cleanup goes as planned. If we destruct
// this class, then Process::~Process() might have problems trying to fully
// destroy the broadcaster.
Finalize();
}
void ScriptedProcess::Initialize() {
static llvm::once_flag g_once_flag;
llvm::call_once(g_once_flag, []() {
PluginManager::RegisterPlugin(GetPluginNameStatic(),
GetPluginDescriptionStatic(), CreateInstance);
});
}
void ScriptedProcess::Terminate() {
PluginManager::UnregisterPlugin(ScriptedProcess::CreateInstance);
}
ConstString ScriptedProcess::GetPluginName() { return GetPluginNameStatic(); }
uint32_t ScriptedProcess::GetPluginVersion() { return 1; }
Status ScriptedProcess::DoLoadCore() {
ProcessLaunchInfo launch_info = GetTarget().GetProcessLaunchInfo();
return DoLaunch(nullptr, launch_info);
}
Status ScriptedProcess::DoLaunch(Module *exe_module,
ProcessLaunchInfo &launch_info) {
CheckInterpreterAndScriptObject();
/* FIXME: This doesn't reflect how lldb actually launches a process.
In reality, it attaches to debugserver, then resume the process. */
Status error = GetInterface().Launch();
SetPrivateState(eStateRunning);
if (error.Fail())
return error;
// TODO: Fetch next state from stopped event queue then send stop event
// const StateType state = SetThreadStopInfo(response);
// if (state != eStateInvalid) {
// SetPrivateState(state);
SetPrivateState(eStateStopped);
UpdateThreadListIfNeeded();
GetThreadList();
return {};
}
void ScriptedProcess::DidLaunch() {
CheckInterpreterAndScriptObject();
m_pid = GetInterface().GetProcessID();
}
Status ScriptedProcess::DoResume() {
CheckInterpreterAndScriptObject();
Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
// FIXME: Fetch data from thread.
const StateType thread_resume_state = eStateRunning;
LLDB_LOGF(log, "ScriptedProcess::%s thread_resume_state = %s", __FUNCTION__,
StateAsCString(thread_resume_state));
bool resume = (thread_resume_state == eStateRunning);
assert(thread_resume_state == eStateRunning && "invalid thread resume state");
Status error;
if (resume) {
LLDB_LOGF(log, "ScriptedProcess::%s sending resume", __FUNCTION__);
SetPrivateState(eStateRunning);
SetPrivateState(eStateStopped);
error = GetInterface().Resume();
}
return error;
}
Status ScriptedProcess::DoStop() {
CheckInterpreterAndScriptObject();
Log *log(lldb_private::GetLogIfAllCategoriesSet(LIBLLDB_LOG_PROCESS));
if (GetInterface().ShouldStop()) {
SetPrivateState(eStateStopped);
LLDB_LOGF(log, "ScriptedProcess::%s Immediate stop", __FUNCTION__);
return {};
}
LLDB_LOGF(log, "ScriptedProcess::%s Delayed stop", __FUNCTION__);
return GetInterface().Stop();
}
Status ScriptedProcess::DoDestroy() { return Status(); }
bool ScriptedProcess::IsAlive() {
if (m_interpreter && m_script_object_sp)
return GetInterface().IsAlive();
return false;
}
size_t ScriptedProcess::DoReadMemory(lldb::addr_t addr, void *buf, size_t size,
Status &error) {
auto error_with_message = [&error](llvm::StringRef message) {
error.SetErrorString(message);
return 0;
};
if (!m_interpreter)
return error_with_message("No interpreter.");
lldb::DataExtractorSP data_extractor_sp =
GetInterface().ReadMemoryAtAddress(addr, size, error);
if (!data_extractor_sp || error.Fail())
return 0;
offset_t bytes_copied = data_extractor_sp->CopyByteOrderedData(
0, data_extractor_sp->GetByteSize(), buf, size, GetByteOrder());
if (!bytes_copied || bytes_copied == LLDB_INVALID_OFFSET)
return error_with_message("Failed to copy read memory to buffer.");
return size;
}
ArchSpec ScriptedProcess::GetArchitecture() {
return GetTarget().GetArchitecture();
}
Status ScriptedProcess::GetMemoryRegionInfo(lldb::addr_t load_addr,
MemoryRegionInfo &region) {
// TODO: Implement
return Status();
}
Status ScriptedProcess::GetMemoryRegions(MemoryRegionInfos &region_list) {
CheckInterpreterAndScriptObject();
lldb::addr_t address = 0;
lldb::MemoryRegionInfoSP mem_region_sp = nullptr;
while ((mem_region_sp =
GetInterface().GetMemoryRegionContainingAddress(address))) {
auto range = mem_region_sp->GetRange();
address += range.GetRangeBase() + range.GetByteSize();
region_list.push_back(*mem_region_sp.get());
}
return {};
}
void ScriptedProcess::Clear() { Process::m_thread_list.Clear(); }
bool ScriptedProcess::DoUpdateThreadList(ThreadList &old_thread_list,
ThreadList &new_thread_list) {
// TODO: Implement
// This is supposed to get the current set of threads, if any of them are in
// old_thread_list then they get copied to new_thread_list, and then any
// actually new threads will get added to new_thread_list.
return new_thread_list.GetSize(false) > 0;
}
bool ScriptedProcess::GetProcessInfo(ProcessInstanceInfo &info) {
info.Clear();
info.SetProcessID(GetID());
info.SetArchitecture(GetArchitecture());
lldb::ModuleSP module_sp = GetTarget().GetExecutableModule();
if (module_sp) {
const bool add_exe_file_as_first_arg = false;
info.SetExecutableFile(GetTarget().GetExecutableModule()->GetFileSpec(),
add_exe_file_as_first_arg);
}
return true;
}
ScriptedProcessInterface &ScriptedProcess::GetInterface() const {
return m_interpreter->GetScriptedProcessInterface();
}