godot/core/debugger/remote_debugger.cpp

737 lines
24 KiB
C++

/**************************************************************************/
/* remote_debugger.cpp */
/**************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/**************************************************************************/
/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur. */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/**************************************************************************/
#include "remote_debugger.h"
#include "core/config/project_settings.h"
#include "core/debugger/debugger_marshalls.h"
#include "core/debugger/engine_debugger.h"
#include "core/debugger/engine_profiler.h"
#include "core/debugger/script_debugger.h"
#include "core/input/input.h"
#include "core/io/resource_loader.h"
#include "core/math/expression.h"
#include "core/object/script_language.h"
#include "core/os/os.h"
#include "servers/display_server.h"
class RemoteDebugger::PerformanceProfiler : public EngineProfiler {
Object *performance = nullptr;
int last_perf_time = 0;
uint64_t last_monitor_modification_time = 0;
public:
void toggle(bool p_enable, const Array &p_opts) {}
void add(const Array &p_data) {}
void tick(double p_frame_time, double p_process_time, double p_physics_time, double p_physics_frame_time) {
if (!performance) {
return;
}
uint64_t pt = OS::get_singleton()->get_ticks_msec();
if (pt - last_perf_time < 1000) {
return;
}
last_perf_time = pt;
Array custom_monitor_names = performance->call("get_custom_monitor_names");
uint64_t monitor_modification_time = performance->call("get_monitor_modification_time");
if (monitor_modification_time > last_monitor_modification_time) {
last_monitor_modification_time = monitor_modification_time;
EngineDebugger::get_singleton()->send_message("performance:profile_names", custom_monitor_names);
}
int max = performance->get("MONITOR_MAX");
Array arr;
arr.resize(max + custom_monitor_names.size());
for (int i = 0; i < max; i++) {
arr[i] = performance->call("get_monitor", i);
}
for (int i = 0; i < custom_monitor_names.size(); i++) {
Variant monitor_value = performance->call("get_custom_monitor", custom_monitor_names[i]);
if (!monitor_value.is_num()) {
ERR_PRINT(vformat("Value of custom monitor '%s' is not a number.", String(custom_monitor_names[i])));
arr[i + max] = Variant();
} else {
arr[i + max] = monitor_value;
}
}
EngineDebugger::get_singleton()->send_message("performance:profile_frame", arr);
}
explicit PerformanceProfiler(Object *p_performance) {
performance = p_performance;
}
};
Error RemoteDebugger::_put_msg(const String &p_message, const Array &p_data) {
Array msg;
msg.push_back(p_message);
msg.push_back(Thread::get_caller_id());
msg.push_back(p_data);
Error err = peer->put_message(msg);
if (err != OK) {
n_messages_dropped++;
}
return err;
}
void RemoteDebugger::_err_handler(void *p_this, const char *p_func, const char *p_file, int p_line, const char *p_err, const char *p_descr, bool p_editor_notify, ErrorHandlerType p_type) {
if (p_type == ERR_HANDLER_SCRIPT) {
return; //ignore script errors, those go through debugger
}
RemoteDebugger *rd = static_cast<RemoteDebugger *>(p_this);
if (rd->flushing && Thread::get_caller_id() == rd->flush_thread) { // Can't handle recursive errors during flush.
return;
}
Vector<ScriptLanguage::StackInfo> si;
for (int i = 0; i < ScriptServer::get_language_count(); i++) {
si = ScriptServer::get_language(i)->debug_get_current_stack_info();
if (si.size()) {
break;
}
}
// send_error will lock internally.
rd->script_debugger->send_error(String::utf8(p_func), String::utf8(p_file), p_line, String::utf8(p_err), String::utf8(p_descr), p_editor_notify, p_type, si);
}
void RemoteDebugger::_print_handler(void *p_this, const String &p_string, bool p_error, bool p_rich) {
RemoteDebugger *rd = static_cast<RemoteDebugger *>(p_this);
if (rd->flushing && Thread::get_caller_id() == rd->flush_thread) { // Can't handle recursive prints during flush.
return;
}
String s = p_string;
int allowed_chars = MIN(MAX(rd->max_chars_per_second - rd->char_count, 0), s.length());
if (allowed_chars == 0 && s.length() > 0) {
return;
}
if (allowed_chars < s.length()) {
s = s.substr(0, allowed_chars);
}
MutexLock lock(rd->mutex);
rd->char_count += allowed_chars;
bool overflowed = rd->char_count >= rd->max_chars_per_second;
if (rd->is_peer_connected()) {
if (overflowed) {
s += "[...]";
}
OutputString output_string;
output_string.message = s;
if (p_error) {
output_string.type = MESSAGE_TYPE_ERROR;
} else if (p_rich) {
output_string.type = MESSAGE_TYPE_LOG_RICH;
} else {
output_string.type = MESSAGE_TYPE_LOG;
}
rd->output_strings.push_back(output_string);
if (overflowed) {
output_string.message = "[output overflow, print less text!]";
output_string.type = MESSAGE_TYPE_ERROR;
rd->output_strings.push_back(output_string);
}
}
}
RemoteDebugger::ErrorMessage RemoteDebugger::_create_overflow_error(const String &p_what, const String &p_descr) {
ErrorMessage oe;
oe.error = p_what;
oe.error_descr = p_descr;
oe.warning = false;
uint64_t time = OS::get_singleton()->get_ticks_msec();
oe.hr = time / 3600000;
oe.min = (time / 60000) % 60;
oe.sec = (time / 1000) % 60;
oe.msec = time % 1000;
return oe;
}
void RemoteDebugger::flush_output() {
MutexLock lock(mutex);
flush_thread = Thread::get_caller_id();
flushing = true;
if (!is_peer_connected()) {
return;
}
if (n_messages_dropped > 0) {
ErrorMessage err_msg = _create_overflow_error("TOO_MANY_MESSAGES", "Too many messages! " + String::num_int64(n_messages_dropped) + " messages were dropped. Profiling might misbheave, try raising 'network/limits/debugger/max_queued_messages' in project setting.");
if (_put_msg("error", err_msg.serialize()) == OK) {
n_messages_dropped = 0;
}
}
if (output_strings.size()) {
// Join output strings so we generate less messages.
Vector<String> joined_log_strings;
Vector<String> strings;
Vector<int> types;
for (const OutputString &output_string : output_strings) {
if (output_string.type == MESSAGE_TYPE_ERROR) {
if (!joined_log_strings.is_empty()) {
strings.push_back(String("\n").join(joined_log_strings));
types.push_back(MESSAGE_TYPE_LOG);
joined_log_strings.clear();
}
strings.push_back(output_string.message);
types.push_back(MESSAGE_TYPE_ERROR);
} else if (output_string.type == MESSAGE_TYPE_LOG_RICH) {
if (!joined_log_strings.is_empty()) {
strings.push_back(String("\n").join(joined_log_strings));
types.push_back(MESSAGE_TYPE_LOG_RICH);
joined_log_strings.clear();
}
strings.push_back(output_string.message);
types.push_back(MESSAGE_TYPE_LOG_RICH);
} else {
joined_log_strings.push_back(output_string.message);
}
}
if (!joined_log_strings.is_empty()) {
strings.push_back(String("\n").join(joined_log_strings));
types.push_back(MESSAGE_TYPE_LOG);
}
Array arr;
arr.push_back(strings);
arr.push_back(types);
_put_msg("output", arr);
output_strings.clear();
}
while (errors.size()) {
ErrorMessage oe = errors.front()->get();
_put_msg("error", oe.serialize());
errors.pop_front();
}
// Update limits
uint64_t ticks = OS::get_singleton()->get_ticks_usec() / 1000;
if (ticks - last_reset > 1000) {
last_reset = ticks;
char_count = 0;
err_count = 0;
n_errors_dropped = 0;
warn_count = 0;
n_warnings_dropped = 0;
}
flushing = false;
}
void RemoteDebugger::send_message(const String &p_message, const Array &p_args) {
MutexLock lock(mutex);
if (is_peer_connected()) {
_put_msg(p_message, p_args);
}
}
void RemoteDebugger::send_error(const String &p_func, const String &p_file, int p_line, const String &p_err, const String &p_descr, bool p_editor_notify, ErrorHandlerType p_type) {
ErrorMessage oe;
oe.error = p_err;
oe.error_descr = p_descr;
oe.source_file = p_file;
oe.source_line = p_line;
oe.source_func = p_func;
oe.warning = p_type == ERR_HANDLER_WARNING;
uint64_t time = OS::get_singleton()->get_ticks_msec();
oe.hr = time / 3600000;
oe.min = (time / 60000) % 60;
oe.sec = (time / 1000) % 60;
oe.msec = time % 1000;
oe.callstack.append_array(script_debugger->get_error_stack_info());
if (flushing && Thread::get_caller_id() == flush_thread) { // Can't handle recursive errors during flush.
return;
}
MutexLock lock(mutex);
if (oe.warning) {
warn_count++;
} else {
err_count++;
}
if (is_peer_connected()) {
if (oe.warning) {
if (warn_count > max_warnings_per_second) {
n_warnings_dropped++;
if (n_warnings_dropped == 1) {
// Only print one message about dropping per second
ErrorMessage overflow = _create_overflow_error("TOO_MANY_WARNINGS", "Too many warnings! Ignoring warnings for up to 1 second.");
errors.push_back(overflow);
}
} else {
errors.push_back(oe);
}
} else {
if (err_count > max_errors_per_second) {
n_errors_dropped++;
if (n_errors_dropped == 1) {
// Only print one message about dropping per second
ErrorMessage overflow = _create_overflow_error("TOO_MANY_ERRORS", "Too many errors! Ignoring errors for up to 1 second.");
errors.push_back(overflow);
}
} else {
errors.push_back(oe);
}
}
}
}
void RemoteDebugger::_send_stack_vars(List<String> &p_names, List<Variant> &p_vals, int p_type) {
DebuggerMarshalls::ScriptStackVariable stvar;
List<String>::Element *E = p_names.front();
List<Variant>::Element *F = p_vals.front();
while (E) {
stvar.name = E->get();
stvar.value = F->get();
stvar.type = p_type;
send_message("stack_frame_var", stvar.serialize());
E = E->next();
F = F->next();
}
}
Error RemoteDebugger::_try_capture(const String &p_msg, const Array &p_data, bool &r_captured) {
const int idx = p_msg.find_char(':');
r_captured = false;
if (idx < 0) { // No prefix, unknown message.
return OK;
}
const String cap = p_msg.substr(0, idx);
if (!has_capture(cap)) {
return ERR_UNAVAILABLE; // Unknown message...
}
const String msg = p_msg.substr(idx + 1);
return capture_parse(cap, msg, p_data, r_captured);
}
void RemoteDebugger::_poll_messages() {
MutexLock mutex_lock(mutex);
peer->poll();
while (peer->has_message()) {
Array cmd = peer->get_message();
ERR_CONTINUE(cmd.size() != 3);
ERR_CONTINUE(cmd[0].get_type() != Variant::STRING);
ERR_CONTINUE(cmd[1].get_type() != Variant::INT);
ERR_CONTINUE(cmd[2].get_type() != Variant::ARRAY);
Thread::ID thread = cmd[1];
if (!messages.has(thread)) {
continue; // This thread is not around to receive the messages
}
Message msg;
msg.message = cmd[0];
msg.data = cmd[2];
messages[thread].push_back(msg);
}
}
bool RemoteDebugger::_has_messages() {
MutexLock mutex_lock(mutex);
return messages.has(Thread::get_caller_id()) && !messages[Thread::get_caller_id()].is_empty();
}
Array RemoteDebugger::_get_message() {
MutexLock mutex_lock(mutex);
ERR_FAIL_COND_V(!messages.has(Thread::get_caller_id()), Array());
List<Message> &message_list = messages[Thread::get_caller_id()];
ERR_FAIL_COND_V(message_list.is_empty(), Array());
Array msg;
msg.resize(2);
msg[0] = message_list.front()->get().message;
msg[1] = message_list.front()->get().data;
message_list.pop_front();
return msg;
}
void RemoteDebugger::debug(bool p_can_continue, bool p_is_error_breakpoint) {
//this function is called when there is a debugger break (bug on script)
//or when execution is paused from editor
{
MutexLock lock(mutex);
// Tests that require mutex.
if (script_debugger->is_skipping_breakpoints() && !p_is_error_breakpoint) {
return;
}
ERR_FAIL_COND_MSG(!is_peer_connected(), "Script Debugger failed to connect, but being used anyway.");
if (!peer->can_block()) {
return; // Peer does not support blocking IO. We could at least send the error though.
}
}
ScriptLanguage *script_lang = script_debugger->get_break_language();
const String error_str = script_lang ? script_lang->debug_get_error() : "";
Array msg;
msg.push_back(p_can_continue);
msg.push_back(error_str);
ERR_FAIL_NULL(script_lang);
msg.push_back(script_lang->debug_get_stack_level_count() > 0);
msg.push_back(Thread::get_caller_id() == Thread::get_main_id() ? String(RTR("Main Thread")) : itos(Thread::get_caller_id()));
if (allow_focus_steal_fn) {
allow_focus_steal_fn();
}
send_message("debug_enter", msg);
Input::MouseMode mouse_mode = Input::MOUSE_MODE_VISIBLE;
if (Thread::get_caller_id() == Thread::get_main_id()) {
mouse_mode = Input::get_singleton()->get_mouse_mode();
if (mouse_mode != Input::MOUSE_MODE_VISIBLE) {
Input::get_singleton()->set_mouse_mode(Input::MOUSE_MODE_VISIBLE);
}
} else {
MutexLock mutex_lock(mutex);
messages.insert(Thread::get_caller_id(), List<Message>());
}
while (is_peer_connected()) {
flush_output();
_poll_messages();
if (_has_messages()) {
Array cmd = _get_message();
ERR_CONTINUE(cmd.size() != 2);
ERR_CONTINUE(cmd[0].get_type() != Variant::STRING);
ERR_CONTINUE(cmd[1].get_type() != Variant::ARRAY);
String command = cmd[0];
Array data = cmd[1];
if (command == "step") {
script_debugger->set_depth(-1);
script_debugger->set_lines_left(1);
break;
} else if (command == "next") {
script_debugger->set_depth(0);
script_debugger->set_lines_left(1);
break;
} else if (command == "continue") {
script_debugger->set_depth(-1);
script_debugger->set_lines_left(-1);
break;
} else if (command == "break") {
ERR_PRINT("Got break when already broke!");
break;
} else if (command == "get_stack_dump") {
DebuggerMarshalls::ScriptStackDump dump;
int slc = script_lang->debug_get_stack_level_count();
for (int i = 0; i < slc; i++) {
ScriptLanguage::StackInfo frame;
frame.file = script_lang->debug_get_stack_level_source(i);
frame.line = script_lang->debug_get_stack_level_line(i);
frame.func = script_lang->debug_get_stack_level_function(i);
dump.frames.push_back(frame);
}
send_message("stack_dump", dump.serialize());
} else if (command == "get_stack_frame_vars") {
ERR_FAIL_COND(data.size() != 1);
ERR_FAIL_NULL(script_lang);
int lv = data[0];
List<String> members;
List<Variant> member_vals;
if (ScriptInstance *inst = script_lang->debug_get_stack_level_instance(lv)) {
members.push_back("self");
member_vals.push_back(inst->get_owner());
}
script_lang->debug_get_stack_level_members(lv, &members, &member_vals);
ERR_FAIL_COND(members.size() != member_vals.size());
List<String> locals;
List<Variant> local_vals;
script_lang->debug_get_stack_level_locals(lv, &locals, &local_vals);
ERR_FAIL_COND(locals.size() != local_vals.size());
List<String> globals;
List<Variant> globals_vals;
script_lang->debug_get_globals(&globals, &globals_vals);
ERR_FAIL_COND(globals.size() != globals_vals.size());
Array var_size;
var_size.push_back(local_vals.size() + member_vals.size() + globals_vals.size());
send_message("stack_frame_vars", var_size);
_send_stack_vars(locals, local_vals, 0);
_send_stack_vars(members, member_vals, 1);
_send_stack_vars(globals, globals_vals, 2);
} else if (command == "reload_scripts") {
script_paths_to_reload = data;
} else if (command == "reload_all_scripts") {
reload_all_scripts = true;
} else if (command == "breakpoint") {
ERR_FAIL_COND(data.size() < 3);
bool set = data[2];
if (set) {
script_debugger->insert_breakpoint(data[1], data[0]);
} else {
script_debugger->remove_breakpoint(data[1], data[0]);
}
} else if (command == "set_skip_breakpoints") {
ERR_FAIL_COND(data.is_empty());
script_debugger->set_skip_breakpoints(data[0]);
} else if (command == "evaluate") {
String expression_str = data[0];
int frame = data[1];
ScriptInstance *breaked_instance = script_debugger->get_break_language()->debug_get_stack_level_instance(frame);
if (!breaked_instance) {
break;
}
List<String> locals;
List<Variant> local_vals;
script_debugger->get_break_language()->debug_get_stack_level_locals(frame, &locals, &local_vals);
ERR_FAIL_COND(locals.size() != local_vals.size());
PackedStringArray locals_vector;
for (const String &S : locals) {
locals_vector.append(S);
}
Array local_vals_array;
for (const Variant &V : local_vals) {
local_vals_array.append(V);
}
Expression expression;
expression.parse(expression_str, locals_vector);
const Variant return_val = expression.execute(local_vals_array, breaked_instance->get_owner());
DebuggerMarshalls::ScriptStackVariable stvar;
stvar.name = expression_str;
stvar.value = return_val;
stvar.type = 3;
send_message("evaluation_return", stvar.serialize());
} else {
bool captured = false;
ERR_CONTINUE(_try_capture(command, data, captured) != OK);
if (!captured) {
WARN_PRINT(vformat("Unknown message received from debugger: %s.", command));
}
}
} else {
OS::get_singleton()->delay_usec(10000);
if (Thread::get_caller_id() == Thread::get_main_id()) {
// If this is a busy loop on the main thread, events still need to be processed.
DisplayServer::get_singleton()->force_process_and_drop_events();
}
}
}
send_message("debug_exit", Array());
if (Thread::get_caller_id() == Thread::get_main_id()) {
if (mouse_mode != Input::MOUSE_MODE_VISIBLE) {
Input::get_singleton()->set_mouse_mode(mouse_mode);
}
} else {
MutexLock mutex_lock(mutex);
messages.erase(Thread::get_caller_id());
}
}
void RemoteDebugger::poll_events(bool p_is_idle) {
if (peer.is_null()) {
return;
}
flush_output();
_poll_messages();
while (_has_messages()) {
Array arr = _get_message();
ERR_CONTINUE(arr.size() != 2);
ERR_CONTINUE(arr[0].get_type() != Variant::STRING);
ERR_CONTINUE(arr[1].get_type() != Variant::ARRAY);
const String cmd = arr[0];
const int idx = cmd.find_char(':');
bool parsed = false;
if (idx < 0) { // Not prefix, use scripts capture.
capture_parse("core", cmd, arr[1], parsed);
continue;
}
const String cap = cmd.substr(0, idx);
if (!has_capture(cap)) {
continue; // Unknown message...
}
const String msg = cmd.substr(idx + 1);
capture_parse(cap, msg, arr[1], parsed);
}
// Reload scripts during idle poll only.
if (p_is_idle) {
if (reload_all_scripts) {
for (int i = 0; i < ScriptServer::get_language_count(); i++) {
ScriptServer::get_language(i)->reload_all_scripts();
}
reload_all_scripts = false;
} else if (!script_paths_to_reload.is_empty()) {
Array scripts_to_reload;
for (int i = 0; i < script_paths_to_reload.size(); ++i) {
String path = script_paths_to_reload[i];
Error err = OK;
Ref<Script> script = ResourceLoader::load(path, "", ResourceFormatLoader::CACHE_MODE_REUSE, &err);
ERR_CONTINUE_MSG(err != OK, vformat("Could not reload script '%s': %s", path, error_names[err]));
ERR_CONTINUE_MSG(script.is_null(), vformat("Could not reload script '%s': Not a script!", path, error_names[err]));
scripts_to_reload.push_back(script);
}
for (int i = 0; i < ScriptServer::get_language_count(); i++) {
ScriptServer::get_language(i)->reload_scripts(scripts_to_reload, true);
}
}
script_paths_to_reload.clear();
}
}
Error RemoteDebugger::_core_capture(const String &p_cmd, const Array &p_data, bool &r_captured) {
r_captured = true;
if (p_cmd == "reload_scripts") {
script_paths_to_reload = p_data;
} else if (p_cmd == "reload_all_scripts") {
reload_all_scripts = true;
} else if (p_cmd == "breakpoint") {
ERR_FAIL_COND_V(p_data.size() < 3, ERR_INVALID_DATA);
bool set = p_data[2];
if (set) {
script_debugger->insert_breakpoint(p_data[1], p_data[0]);
} else {
script_debugger->remove_breakpoint(p_data[1], p_data[0]);
}
} else if (p_cmd == "set_skip_breakpoints") {
ERR_FAIL_COND_V(p_data.is_empty(), ERR_INVALID_DATA);
script_debugger->set_skip_breakpoints(p_data[0]);
} else if (p_cmd == "break") {
script_debugger->debug(script_debugger->get_break_language());
} else {
r_captured = false;
}
return OK;
}
Error RemoteDebugger::_profiler_capture(const String &p_cmd, const Array &p_data, bool &r_captured) {
r_captured = false;
ERR_FAIL_COND_V(p_data.is_empty(), ERR_INVALID_DATA);
ERR_FAIL_COND_V(p_data[0].get_type() != Variant::BOOL, ERR_INVALID_DATA);
ERR_FAIL_COND_V(!has_profiler(p_cmd), ERR_UNAVAILABLE);
Array opts;
if (p_data.size() > 1) { // Optional profiler parameters.
ERR_FAIL_COND_V(p_data[1].get_type() != Variant::ARRAY, ERR_INVALID_DATA);
opts = p_data[1];
}
r_captured = true;
profiler_enable(p_cmd, p_data[0], opts);
return OK;
}
RemoteDebugger::RemoteDebugger(Ref<RemoteDebuggerPeer> p_peer) {
peer = p_peer;
max_chars_per_second = GLOBAL_GET("network/limits/debugger/max_chars_per_second");
max_errors_per_second = GLOBAL_GET("network/limits/debugger/max_errors_per_second");
max_warnings_per_second = GLOBAL_GET("network/limits/debugger/max_warnings_per_second");
// Performance Profiler
Object *perf = Engine::get_singleton()->get_singleton_object("Performance");
if (perf) {
performance_profiler.instantiate(perf);
performance_profiler->bind("performance");
profiler_enable("performance", true);
}
// Core and profiler captures.
Capture core_cap(this,
[](void *p_user, const String &p_cmd, const Array &p_data, bool &r_captured) {
return static_cast<RemoteDebugger *>(p_user)->_core_capture(p_cmd, p_data, r_captured);
});
register_message_capture("core", core_cap);
Capture profiler_cap(this,
[](void *p_user, const String &p_cmd, const Array &p_data, bool &r_captured) {
return static_cast<RemoteDebugger *>(p_user)->_profiler_capture(p_cmd, p_data, r_captured);
});
register_message_capture("profiler", profiler_cap);
// Error handlers
phl.printfunc = _print_handler;
phl.userdata = this;
add_print_handler(&phl);
eh.errfunc = _err_handler;
eh.userdata = this;
add_error_handler(&eh);
messages.insert(Thread::get_main_id(), List<Message>());
}
RemoteDebugger::~RemoteDebugger() {
remove_print_handler(&phl);
remove_error_handler(&eh);
}