X-Git-Url: http://bilbo.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/100b572b5cdf8a4762953413ddb28be5a66b8af5..0656c27cac6242675aba1df0f3c1ef6a79275e0c:/examples/s4u/mc-bugged1-liveness/s4u-mc-bugged1-liveness.cpp

diff --git a/examples/s4u/mc-bugged1-liveness/s4u-mc-bugged1-liveness.cpp b/examples/s4u/mc-bugged1-liveness/s4u-mc-bugged1-liveness.cpp
new file mode 100644
index 0000000000..9df987210f
--- /dev/null
+++ b/examples/s4u/mc-bugged1-liveness/s4u-mc-bugged1-liveness.cpp
@@ -0,0 +1,161 @@
+/* Copyright (c) 2012-2020. 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. */
+
+/***************** Centralized Mutual Exclusion Algorithm *******************/
+/* This example implements a centralized mutual exclusion algorithm.        */
+/* Bug : CS requests of client 1 not satisfied                              */
+/* LTL property checked : G(r->F(cs)); (r=request of CS, cs=CS ok)          */
+/****************************************************************************/
+
+#ifdef GARBAGE_STACK
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#endif
+
+#include <simgrid/modelchecker.h>
+#include <simgrid/s4u.hpp>
+#include <xbt/dynar.h>
+
+XBT_LOG_NEW_DEFAULT_CATEGORY(bugged1_liveness, "my log messages");
+
+class Message {
+public:
+  enum class Kind { GRANT, REQUEST, RELEASE };
+  Kind kind                             = Kind::GRANT;
+  simgrid::s4u::Mailbox* return_mailbox = nullptr;
+  explicit Message(Message::Kind kind, simgrid::s4u::Mailbox* mbox) : kind(kind), return_mailbox(mbox) {}
+};
+
+int r  = 0;
+int cs = 0;
+
+#ifdef GARBAGE_STACK
+/** Do not use a clean stack */
+static void garbage_stack(void)
+{
+  const size_t size = 256;
+  int fd            = open("/dev/urandom", O_RDONLY);
+  char foo[size];
+  read(fd, foo, size);
+  close(fd);
+}
+#endif
+
+static void coordinator()
+{
+  int CS_used = 0;
+  Message* m  = nullptr;
+  std::queue<simgrid::s4u::Mailbox*> requests;
+
+  simgrid::s4u::Mailbox* mbox = simgrid::s4u::Mailbox::by_name("coordinator");
+
+  while (1) {
+    m = static_cast<Message*>(mbox->get());
+    if (m->kind == Message::Kind::REQUEST) {
+      if (CS_used) {
+        XBT_INFO("CS already used. Queue the request.");
+        requests.push(m->return_mailbox);
+      } else {
+        if (m->return_mailbox->get_name() != "1") {
+          XBT_INFO("CS idle. Grant immediatly");
+          m->return_mailbox->put(new Message(Message::Kind::GRANT, mbox), 1000);
+          CS_used = 1;
+        }
+      }
+    } else {
+      if (not requests.empty()) {
+        XBT_INFO("CS release. Grant to queued requests (queue size: %zu)", requests.size());
+        simgrid::s4u::Mailbox* req = requests.front();
+        requests.pop();
+        if (req->get_name() != "1") {
+          req->put(new Message(Message::Kind::GRANT, mbox), 1000);
+        } else {
+          requests.push(req);
+          CS_used = 0;
+        }
+      } else {
+        XBT_INFO("CS release. resource now idle");
+        CS_used = 0;
+      }
+    }
+    delete m;
+  }
+}
+
+static void client(int id)
+{
+  int my_pid = simgrid::s4u::this_actor::get_pid();
+
+  simgrid::s4u::Mailbox* my_mailbox = simgrid::s4u::Mailbox::by_name(std::to_string(id));
+
+  while (1) {
+    XBT_INFO("Ask the request");
+    simgrid::s4u::Mailbox::by_name("coordinator")->put(new Message(Message::Kind::REQUEST, my_mailbox), 1000);
+
+    if (id == 1) {
+      r  = 1;
+      cs = 0;
+      XBT_INFO("Propositions changed : r=1, cs=0");
+    }
+
+    Message* grant = static_cast<Message*>(my_mailbox->get());
+
+    if ((id == 1) && (grant->kind == Message::Kind::GRANT)) {
+      cs = 1;
+      r  = 0;
+      XBT_INFO("Propositions changed : r=0, cs=1");
+    }
+
+    delete grant;
+
+    XBT_INFO("%d got the answer. Sleep a bit and release it", id);
+
+    simgrid::s4u::this_actor::sleep_for(1);
+
+    simgrid::s4u::Mailbox::by_name("coordinator")->put(new Message(Message::Kind::RELEASE, my_mailbox), 1000);
+
+    simgrid::s4u::this_actor::sleep_for(my_pid);
+
+    if (id == 1) {
+      cs = 0;
+      r  = 0;
+      XBT_INFO("Propositions changed : r=0, cs=0");
+    }
+  }
+}
+
+static void raw_client(int id)
+{
+#ifdef GARBAGE_STACK
+  // At this point the stack of the callee (client) is probably filled with
+  // zeros and uninitialized variables will contain 0. This call will place
+  // random byes in the stack of the callee:
+  garbage_stack();
+#endif
+  client(id);
+}
+
+int main(int argc, char* argv[])
+{
+  simgrid::s4u::Engine e(&argc, argv);
+
+  MC_automaton_new_propositional_symbol_pointer("r", &r);
+  MC_automaton_new_propositional_symbol_pointer("cs", &cs);
+
+  e.load_platform(argv[1]);
+
+  simgrid::s4u::Actor::create("coordinator", simgrid::s4u::Host::by_name("Tremblay"), coordinator);
+  if (std::stod(argv[2]) == 0) {
+    simgrid::s4u::Actor::create("client", simgrid::s4u::Host::by_name("Boivin"), raw_client, 1);
+    simgrid::s4u::Actor::create("client", simgrid::s4u::Host::by_name("Fafard"), raw_client, 2);
+  } else { // "Visited" case
+    simgrid::s4u::Actor::create("client", simgrid::s4u::Host::by_name("Boivin"), raw_client, 2);
+    simgrid::s4u::Actor::create("client", simgrid::s4u::Host::by_name("Fafard"), raw_client, 1);
+  }
+  e.run();
+
+  return 0;
+}