-/* Copyright (c) 2007-2021. The SimGrid Team. All rights reserved. */
+/* Copyright (c) 2007-2023. The SimGrid Team. All rights reserved. */
/* This program is free software; you can redistribute it and/or modify it
* under the terms of the license (GNU LGPL) which comes with this package. */
#include "src/mc/remote/CheckerSide.hpp"
+#include "src/mc/explo/Exploration.hpp"
+#include "src/mc/explo/LivenessChecker.hpp"
+#include "src/mc/sosp/RemoteProcessMemory.hpp"
+#include "xbt/system_error.hpp"
+
#include <csignal>
+#include <sys/ptrace.h>
#include <sys/wait.h>
-namespace simgrid {
-namespace mc {
+XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_checkerside, mc, "MC communication with the application");
-CheckerSide::~CheckerSide()
+namespace simgrid::mc {
+CheckerSide::CheckerSide(int sockfd, pid_t pid) : channel_(sockfd), running_(true), pid_(pid)
{
- if (socket_event_ != nullptr)
- event_free(socket_event_);
- if (signal_event_ != nullptr)
- event_free(signal_event_);
- if (base_ != nullptr)
- event_base_free(base_);
+ auto* base = event_base_new();
+ base_.reset(base);
+
+ auto* socket_event = event_new(
+ base, get_channel().get_socket(), EV_READ | EV_PERSIST,
+ [](evutil_socket_t sig, short events, void* arg) {
+ auto checker = static_cast<simgrid::mc::CheckerSide*>(arg);
+ if (events == EV_READ) {
+ std::array<char, MC_MESSAGE_LENGTH> buffer;
+ ssize_t size = recv(checker->get_channel().get_socket(), buffer.data(), buffer.size(), MSG_DONTWAIT);
+ if (size == -1) {
+ XBT_ERROR("Channel::receive failure: %s", strerror(errno));
+ if (errno != EAGAIN)
+ throw simgrid::xbt::errno_error();
+ }
+
+ if (not checker->handle_message(buffer.data(), size))
+ checker->break_loop();
+ } else {
+ xbt_die("Unexpected event");
+ }
+ },
+ this);
+ event_add(socket_event, nullptr);
+ socket_event_.reset(socket_event);
+
+ auto* signal_event = event_new(
+ base, SIGCHLD, EV_SIGNAL | EV_PERSIST,
+ [](evutil_socket_t sig, short events, void* arg) {
+ auto checker = static_cast<simgrid::mc::CheckerSide*>(arg);
+ if (events == EV_SIGNAL) {
+ if (sig == SIGCHLD)
+ checker->handle_waitpid();
+ else
+ xbt_die("Unexpected signal: %d", sig);
+ } else {
+ xbt_die("Unexpected event");
+ }
+ },
+ this);
+ event_add(signal_event, nullptr);
+ signal_event_.reset(signal_event);
}
-void CheckerSide::start(void (*handler)(int, short, void*))
+void CheckerSide::dispatch_events() const
{
- base_ = event_base_new();
+ event_base_dispatch(base_.get());
+}
+
+void CheckerSide::break_loop() const
+{
+ event_base_loopbreak(base_.get());
+}
+
+bool CheckerSide::handle_message(const char* buffer, ssize_t size)
+{
+ s_mc_message_t base_message;
+ xbt_assert(size >= (ssize_t)sizeof(base_message), "Broken message");
+ memcpy(&base_message, buffer, sizeof(base_message));
+
+ switch (base_message.type) {
+ case MessageType::INITIAL_ADDRESSES: {
+ s_mc_message_initial_addresses_t message;
+ xbt_assert(size == sizeof(message), "Broken message. Got %d bytes instead of %d.", (int)size,
+ (int)sizeof(message));
+ memcpy(&message, buffer, sizeof(message));
+ /* Create the memory address space, now that we have the mandatory information */
+ remote_memory_ = std::make_unique<simgrid::mc::RemoteProcessMemory>(pid_, message.mmalloc_default_mdp);
+ break;
+ }
- socket_event_ = event_new(base_, get_channel().get_socket(), EV_READ | EV_PERSIST, handler, this);
- event_add(socket_event_, nullptr);
+ case MessageType::IGNORE_HEAP: {
+ s_mc_message_ignore_heap_t message;
+ xbt_assert(size == sizeof(message), "Broken message");
+ memcpy(&message, buffer, sizeof(message));
- signal_event_ = event_new(base_, SIGCHLD, EV_SIGNAL | EV_PERSIST, handler, this);
- event_add(signal_event_, nullptr);
+ IgnoredHeapRegion region;
+ region.block = message.block;
+ region.fragment = message.fragment;
+ region.address = message.address;
+ region.size = message.size;
+ get_remote_memory().ignore_heap(region);
+ break;
+ }
+
+ case MessageType::UNIGNORE_HEAP: {
+ s_mc_message_ignore_memory_t message;
+ xbt_assert(size == sizeof(message), "Broken message");
+ memcpy(&message, buffer, sizeof(message));
+ get_remote_memory().unignore_heap((void*)(std::uintptr_t)message.addr, message.size);
+ break;
+ }
+
+ case MessageType::IGNORE_MEMORY: {
+ s_mc_message_ignore_memory_t message;
+ xbt_assert(size == sizeof(message), "Broken message");
+ memcpy(&message, buffer, sizeof(message));
+ get_remote_memory().ignore_region(message.addr, message.size);
+ break;
+ }
+
+ case MessageType::STACK_REGION: {
+ s_mc_message_stack_region_t message;
+ xbt_assert(size == sizeof(message), "Broken message");
+ memcpy(&message, buffer, sizeof(message));
+ get_remote_memory().stack_areas().push_back(message.stack_region);
+ } break;
+
+ case MessageType::REGISTER_SYMBOL: {
+ s_mc_message_register_symbol_t message;
+ xbt_assert(size == sizeof(message), "Broken message");
+ memcpy(&message, buffer, sizeof(message));
+ xbt_assert(not message.callback, "Support for client-side function proposition is not implemented.");
+ XBT_DEBUG("Received symbol: %s", message.name.data());
+
+ LivenessChecker::automaton_register_symbol(get_remote_memory(), message.name.data(), remote((int*)message.data));
+ break;
+ }
+
+ case MessageType::WAITING:
+ return false;
+
+ case MessageType::ASSERTION_FAILED:
+ Exploration::get_instance()->report_assertion_failure();
+ break;
+
+ default:
+ xbt_die("Unexpected message from model-checked application");
+ }
+ return true;
}
-void CheckerSide::dispatch()
+void CheckerSide::clear_memory_cache()
{
- event_base_dispatch(base_);
+ if (remote_memory_)
+ remote_memory_->clear_cache();
}
-void CheckerSide::break_loop()
+void CheckerSide::handle_waitpid()
{
- event_base_loopbreak(base_);
+ XBT_DEBUG("Check for wait event");
+ int status;
+ pid_t pid;
+ while ((pid = waitpid(-1, &status, WNOHANG)) != 0) {
+ if (pid == -1) {
+ if (errno == ECHILD) { // No more children:
+ xbt_assert(not this->running(), "Inconsistent state");
+ break;
+ } else {
+ XBT_ERROR("Could not wait for pid");
+ throw simgrid::xbt::errno_error();
+ }
+ }
+
+ if (pid == get_pid()) {
+ // From PTRACE_O_TRACEEXIT:
+#ifdef __linux__
+ if (status >> 8 == (SIGTRAP | (PTRACE_EVENT_EXIT << 8))) {
+ unsigned long eventmsg;
+ xbt_assert(ptrace(PTRACE_GETEVENTMSG, pid, 0, &eventmsg) != -1, "Could not get exit status");
+ status = static_cast<int>(eventmsg);
+ if (WIFSIGNALED(status)) {
+ this->terminate();
+ Exploration::get_instance()->report_crash(status);
+ }
+ }
+#endif
+
+ // We don't care about non-lethal signals, just reinject them:
+ if (WIFSTOPPED(status)) {
+ XBT_DEBUG("Stopped with signal %i", (int)WSTOPSIG(status));
+ errno = 0;
+#ifdef __linux__
+ ptrace(PTRACE_CONT, pid, 0, WSTOPSIG(status));
+#elif defined BSD
+ ptrace(PT_CONTINUE, pid, (caddr_t)1, WSTOPSIG(status));
+#endif
+ xbt_assert(errno == 0, "Could not PTRACE_CONT");
+ }
+
+ else if (WIFSIGNALED(status)) {
+ this->terminate();
+ Exploration::get_instance()->report_crash(status);
+ } else if (WIFEXITED(status)) {
+ XBT_DEBUG("Child process is over");
+ this->terminate();
+ }
+ }
+ }
}
-} // namespace mc
-} // namespace simgrid
+} // namespace simgrid::mc
