+++ /dev/null
-/* Copyright (c) 2015. 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 <memory>
-#include <system_error>
-
-#include <poll.h>
-#include <sys/types.h>
-#include <sys/wait.h>
-#include <sys/socket.h>
-#include <sys/signalfd.h>
-#include <sys/ptrace.h>
-
-#include <xbt/log.h>
-#include <xbt/automaton.h>
-#include <xbt/automaton.hpp>
-
-#include "ModelChecker.hpp"
-#include "mc_protocol.h"
-#include "mc_server.h"
-#include "mc_private.h"
-#include "mc_ignore.h"
-#include "mcer_ignore.h"
-#include "mc_exit.h"
-#include "src/mc/mc_liveness.h"
-
-using simgrid::mc::remote;
-
-extern "C" {
-
-XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_server, mc, "MC server logic");
-
-// HArdcoded index for now:
-#define SOCKET_FD_INDEX 0
-#define SIGNAL_FD_INDEX 1
-
-mc_server_t mc_server;
-
-s_mc_server::s_mc_server(pid_t pid_, int socket_)
- : pid(pid_), socket(socket_) {}
-
-void s_mc_server::start()
-{
- // Block SIGCHLD (this will be handled with accept/signalfd):
- sigset_t set;
- sigemptyset(&set);
- sigaddset(&set, SIGCHLD);
- if (sigprocmask(SIG_BLOCK, &set, NULL) == -1)
- throw std::system_error(errno, std::system_category());
-
- sigset_t full_set;
- sigfillset(&full_set);
-
- // Prepare data for poll:
-
- struct pollfd* socket_pollfd = &fds[SOCKET_FD_INDEX];
- socket_pollfd->fd = socket;
- socket_pollfd->events = POLLIN;
- socket_pollfd->revents = 0;
-
- int signal_fd = signalfd(-1, &set, 0);
- if (signal_fd == -1)
- throw std::system_error(errno, std::system_category());
-
- struct pollfd* signalfd_pollfd = &fds[SIGNAL_FD_INDEX];
- signalfd_pollfd->fd = signal_fd;
- signalfd_pollfd->events = POLLIN;
- signalfd_pollfd->revents = 0;
-
- XBT_DEBUG("Waiting for the model-checked process");
- int status;
-
- // The model-checked process SIGSTOP itself to signal it's ready:
- pid_t res = waitpid(pid, &status, __WALL);
- if (res < 0 || !WIFSTOPPED(status) || WSTOPSIG(status) != SIGSTOP)
- xbt_die("Could not wait model-checked process");
-
- // The model-checked process is ready, we can read its memory layout:
- MC_init_model_checker(pid, socket);
-
- ptrace(PTRACE_SETOPTIONS, pid, nullptr, PTRACE_O_TRACEEXIT);
- ptrace(PTRACE_CONT, pid, 0, 0);
-}
-
-void s_mc_server::shutdown()
-{
- XBT_DEBUG("Shuting down model-checker");
-
- simgrid::mc::Process* process = &mc_model_checker->process();
- int status = process->status();
- if (process->running()) {
- XBT_DEBUG("Killing process");
- kill(process->pid(), SIGTERM);
- if (waitpid(process->pid(), &status, 0) == -1)
- throw std::system_error(errno, std::system_category());
- // TODO, handle the case when the process does not want to die with a timeout
- process->terminate(status);
- }
-}
-
-void s_mc_server::exit()
-{
- // Finished:
- int status = mc_model_checker->process().status();
- if (WIFEXITED(status))
- ::exit(WEXITSTATUS(status));
- else if (WIFSIGNALED(status)) {
- // Try to uplicate the signal of the model-checked process.
- // This is a temporary hack so we don't try too hard.
- kill(mc_model_checker->process().pid(), WTERMSIG(status));
- abort();
- } else {
- xbt_die("Unexpected status from model-checked process");
- }
-}
-
-void s_mc_server::resume(simgrid::mc::Process& process)
-{
- int res = process.send_message(MC_MESSAGE_CONTINUE);
- if (res)
- throw std::system_error(res, std::system_category());
- process.cache_flags = (mc_process_cache_flags_t) 0;
-}
-
-static
-void throw_socket_error(int fd)
-{
- int error = 0;
- socklen_t errlen = sizeof(error);
- if (getsockopt(fd, SOL_SOCKET, SO_ERROR, (void *)&error, &errlen) == -1)
- error = errno;
- throw std::system_error(error, std::system_category());
-}
-
-bool s_mc_server::handle_message(char* buffer, ssize_t size)
-{
- s_mc_message_t base_message;
- if (size < (ssize_t) sizeof(base_message))
- xbt_die("Broken message");
- memcpy(&base_message, buffer, sizeof(base_message));
-
- switch(base_message.type) {
-
- case MC_MESSAGE_IGNORE_HEAP:
- {
- s_mc_ignore_heap_message_t message;
- if (size != sizeof(message))
- xbt_die("Broken messsage");
- memcpy(&message, buffer, sizeof(message));
- mc_heap_ignore_region_t region = xbt_new(s_mc_heap_ignore_region_t, 1);
- *region = message.region;
- MC_heap_region_ignore_insert(region);
- break;
- }
-
- case MC_MESSAGE_UNIGNORE_HEAP:
- {
- s_mc_ignore_memory_message_t message;
- if (size != sizeof(message))
- xbt_die("Broken messsage");
- memcpy(&message, buffer, sizeof(message));
- MC_heap_region_ignore_remove(
- (void *)(std::uintptr_t) message.addr, message.size);
- break;
- }
-
- case MC_MESSAGE_IGNORE_MEMORY:
- {
- s_mc_ignore_memory_message_t message;
- if (size != sizeof(message))
- xbt_die("Broken messsage");
- memcpy(&message, buffer, sizeof(message));
- mc_model_checker->process().ignore_region(
- message.addr, message.size);
- break;
- }
-
- case MC_MESSAGE_STACK_REGION:
- {
- s_mc_stack_region_message_t message;
- if (size != sizeof(message))
- xbt_die("Broken messsage");
- memcpy(&message, buffer, sizeof(message));
- stack_region_t stack_region = xbt_new(s_stack_region_t, 1);
- *stack_region = message.stack_region;
- MC_stack_area_add(stack_region);
- }
- break;
-
- case MC_MESSAGE_REGISTER_SYMBOL:
- {
- s_mc_register_symbol_message_t message;
- if (size != sizeof(message))
- xbt_die("Broken message");
- memcpy(&message, buffer, sizeof(message));
- if (message.callback)
- xbt_die("Support for client-side function proposition is not implemented.");
- XBT_DEBUG("Received symbol: %s", message.name);
-
- if (_mc_property_automaton == NULL)
- _mc_property_automaton = xbt_automaton_new();
-
- simgrid::mc::Process* process = &mc_model_checker->process();
- simgrid::mc::remote_ptr<int> address
- = simgrid::mc::remote((int*) message.data);
- simgrid::xbt::add_proposition(_mc_property_automaton,
- message.name,
- [process, address]() { return process->read(address); }
- );
-
- break;
- }
-
- case MC_MESSAGE_WAITING:
- return false;
-
- case MC_MESSAGE_ASSERTION_FAILED:
- MC_report_assertion_error();
- ::exit(SIMGRID_EXIT_SAFETY);
- break;
-
- default:
- xbt_die("Unexpected message from model-checked application");
-
- }
- return true;
-}
-
-bool s_mc_server::handle_events()
-{
- char buffer[MC_MESSAGE_LENGTH];
- struct pollfd* socket_pollfd = &fds[SOCKET_FD_INDEX];
- struct pollfd* signalfd_pollfd = &fds[SIGNAL_FD_INDEX];
-
- while(poll(fds, 2, -1) == -1) {
- switch(errno) {
- case EINTR:
- continue;
- default:
- throw std::system_error(errno, std::system_category());
- }
- }
-
- if (socket_pollfd->revents) {
- if (socket_pollfd->revents & POLLIN) {
- ssize_t size = MC_receive_message(socket_pollfd->fd, buffer, sizeof(buffer), MSG_DONTWAIT);
- if (size == -1 && errno != EAGAIN)
- throw std::system_error(errno, std::system_category());
- return handle_message(buffer, size);
- }
- if (socket_pollfd->revents & POLLERR) {
- throw_socket_error(socket_pollfd->fd);
- }
- if (socket_pollfd->revents & POLLHUP)
- xbt_die("Socket hang up?");
- }
-
- if (signalfd_pollfd->revents) {
- if (signalfd_pollfd->revents & POLLIN) {
- this->handle_signals();
- return true;
- }
- if (signalfd_pollfd->revents & POLLERR) {
- throw_socket_error(signalfd_pollfd->fd);
- }
- if (signalfd_pollfd->revents & POLLHUP)
- xbt_die("Signalfd hang up?");
- }
-
- return true;
-}
-
-void s_mc_server::loop()
-{
- while (mc_model_checker->process().running())
- this->handle_events();
-}
-
-void s_mc_server::handle_signals()
-{
- struct signalfd_siginfo info;
- struct pollfd* signalfd_pollfd = &fds[SIGNAL_FD_INDEX];
- while (1) {
- ssize_t size = read(signalfd_pollfd->fd, &info, sizeof(info));
- if (size == -1) {
- if (errno == EINTR)
- continue;
- else
- throw std::system_error(errno, std::system_category());
- } else if (size != sizeof(info))
- return throw std::runtime_error(
- "Bad communication with model-checked application");
- else
- break;
- }
- this->on_signal(&info);
-}
-
-void s_mc_server::handle_waitpid()
-{
- 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:
- if (mc_model_checker->process().running())
- xbt_die("Inconsistent state");
- else
- break;
- } else {
- XBT_ERROR("Could not wait for pid");
- throw std::system_error(errno, std::system_category());
- }
- }
-
- if (pid == mc_model_checker->process().pid()) {
-
- // From PTRACE_O_TRACEEXIT:
- if (status>>8 == (SIGTRAP | (PTRACE_EVENT_EXIT<<8))) {
- if (ptrace(PTRACE_GETEVENTMSG, pid, 0, &status) == -1)
- xbt_die("Could not get exit status");
- if (WIFSIGNALED(status)) {
- MC_report_crash(status);
- ::exit(SIMGRID_PROGRAM_CRASH);
- }
- }
-
- // We don't care about signals, just reinject them:
- if (WIFSTOPPED(status)) {
- XBT_DEBUG("Stopped with signal %i", (int) WSTOPSIG(status));
- if (ptrace(PTRACE_CONT, pid, 0, WSTOPSIG(status)) == -1)
- xbt_die("Could not PTRACE_CONT");
- }
-
- else if (WIFEXITED(status) || WIFSIGNALED(status)) {
- XBT_DEBUG("Child process is over");
- mc_model_checker->process().terminate(status);
- }
- }
- }
-}
-
-void s_mc_server::on_signal(const struct signalfd_siginfo* info)
-{
- switch(info->ssi_signo) {
- case SIGCHLD:
- this->handle_waitpid();
- break;
- default:
- break;
- }
-}
-
-void s_mc_server::wait_client(simgrid::mc::Process& process)
-{
- this->resume(process);
- while (mc_model_checker->process().running()) {
- if (!mc_server->handle_events())
- return;
- }
-}
-
-void s_mc_server::simcall_handle(simgrid::mc::Process& process, unsigned long pid, int value)
-{
- s_mc_simcall_handle_message m;
- memset(&m, 0, sizeof(m));
- m.type = MC_MESSAGE_SIMCALL_HANDLE;
- m.pid = pid;
- m.value = value;
- process.send_message(m);
- process.cache_flags = (mc_process_cache_flags_t) 0;
- while (process.running()) {
- if (!mc_server->handle_events())
- return;
- }
-}
-
-}
