1 /* Copyright (c) 2015-2017. The SimGrid Team.
2 * All rights reserved. */
4 /* This program is free software; you can redistribute it and/or modify it
5 * under the terms of the license (GNU LGPL) which comes with this package. */
13 #include "xbt/system_error.hpp"
15 #include <simgrid/modelchecker.h>
16 #include <simgrid/sg_config.h>
18 #include "src/mc/Session.hpp"
19 #include "src/mc/checker/Checker.hpp"
20 #include "src/mc/mc_private.hpp"
21 #include "src/mc/mc_state.hpp"
23 #include "src/smpi/include/private.hpp"
25 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_Session, mc, "Model-checker session");
26 extern std::string _sg_mc_dot_output_file;
31 static void setup_child_environment(int socket)
34 // Make sure we do not outlive our parent:
37 if (sigprocmask(SIG_SETMASK, &mask, nullptr) < 0)
38 throw simgrid::xbt::errno_error("Could not unblock signals");
39 if (prctl(PR_SET_PDEATHSIG, SIGHUP) != 0)
40 throw simgrid::xbt::errno_error("Could not PR_SET_PDEATHSIG");
45 // Remove CLOEXEC in order to pass the socket to the exec-ed program:
46 int fdflags = fcntl(socket, F_GETFD, 0);
47 if (fdflags == -1 || fcntl(socket, F_SETFD, fdflags & ~FD_CLOEXEC) == -1)
48 throw simgrid::xbt::errno_error("Could not remove CLOEXEC for socket");
51 setenv(MC_ENV_VARIABLE, "1", 1);
53 // Disable lazy relocation in the model-checked process.
54 // We don't want the model-checked process to modify its .got.plt during
56 setenv("LC_BIND_NOW", "1", 1);
59 res = std::snprintf(buffer, sizeof(buffer), "%i", socket);
60 if ((size_t) res >= sizeof(buffer) || res == -1)
62 setenv(MC_ENV_SOCKET_FD, buffer, 1);
65 /** Execute some code in a forked process */
72 throw simgrid::xbt::errno_error("Could not fork model-checked process");
82 // The callback should catch exceptions:
87 Session::Session(pid_t pid, int socket)
89 std::unique_ptr<simgrid::mc::RemoteClient> process(new simgrid::mc::RemoteClient(pid, socket));
90 // TODO, automatic detection of the config from the process
91 process->privatized(smpi_privatize_global_variables != SMPI_PRIVATIZE_NONE);
92 modelChecker_ = std::unique_ptr<ModelChecker>(
93 new simgrid::mc::ModelChecker(std::move(process)));
94 xbt_assert(mc_model_checker == nullptr);
95 mc_model_checker = modelChecker_.get();
96 mc_model_checker->start();
104 void Session::initialize()
106 xbt_assert(initialSnapshot_ == nullptr);
107 mc_model_checker->wait_for_requests();
108 initialSnapshot_ = simgrid::mc::take_snapshot(0);
111 void Session::execute(Transition const& transition)
113 modelChecker_->handle_simcall(transition);
114 modelChecker_->wait_for_requests();
117 void Session::restoreInitialState()
119 simgrid::mc::restore_snapshot(this->initialSnapshot_);
122 void Session::logState()
124 mc_model_checker->getChecker()->logState();
126 if (not _sg_mc_dot_output_file.empty()) {
127 fprintf(dot_output, "}\n");
130 if (getenv("SIMGRID_MC_SYSTEM_STATISTICS")){
131 int ret=system("free");
132 if(ret!=0)XBT_WARN("system call did not return 0, but %d",ret);
137 Session* Session::fork(std::function<void()> code)
139 // Create a AF_LOCAL socketpair used for exchanging messages
140 // between the model-checker process (ourselves) and the model-checked
144 res = socketpair(AF_LOCAL, SOCK_SEQPACKET | SOCK_CLOEXEC, 0, sockets);
146 throw simgrid::xbt::errno_error("Could not create socketpair");
148 pid_t pid = do_fork([sockets, &code] {
150 setup_child_environment(sockets[0]);
152 xbt_die("The model-checked process failed to exec()");
155 // Parent (model-checker):
158 return new Session(pid, sockets[1]);
162 Session* Session::spawnv(const char *path, char *const argv[])
164 return Session::fork([path, argv] {
170 Session* Session::spawnvp(const char *file, char *const argv[])
172 return Session::fork([file, argv] {
177 void Session::close()
179 initialSnapshot_ = nullptr;
181 modelChecker_->shutdown();
182 modelChecker_ = nullptr;
183 mc_model_checker = nullptr;
187 simgrid::mc::Session* session;