--- /dev/null
+/***************** Centralized Mutual Exclusion Algorithm *********************/
+/* This example implements a centralized mutual exclusion algorithm. */
+/* There is no bug on it, it is just provided to test the state space */
+/* reduction of DPOR. */
+/******************************************************************************/
+
+#include "msg/msg.h"
+#include "mc/mc.h"
+#include "xbt/automaton.h"
+#include "xbt/automatonparse_promela.h"
+#include "example_liveness_with_cycle.h"
+#include "y.tab.c"
+
+#define AMOUNT_OF_CLIENTS 2
+#define CS_PER_PROCESS 1
+
+XBT_LOG_NEW_DEFAULT_CATEGORY(example_liveness_with_cycle, "my log messages");
+
+int p=0;
+int q=0;
+
+int predP(){
+ return p;
+}
+
+int predQ(){
+ return q;
+}
+
+int coordinator(int argc, char *argv[])
+{
+ xbt_dynar_t requests = xbt_dynar_new(sizeof(char *), NULL); // dynamic vector storing requests (which are char*)
+ int CS_used = 0; // initially the CS is idle
+ int todo = AMOUNT_OF_CLIENTS * CS_PER_PROCESS; // amount of releases we are expecting
+ while (todo > 0) {
+ m_task_t task = NULL;
+ MSG_task_receive(&task, "coordinator");
+ const char *kind = MSG_task_get_name(task); //is it a request or a release?
+ if (!strcmp(kind, "request")) { // that's a request
+ char *req = MSG_task_get_data(task);
+ //XBT_INFO("Req %s", req);
+ if (CS_used) { // need to push the request in the vector
+ XBT_INFO("CS already used. Queue the request");
+ xbt_dynar_push(requests, &req);
+ } else { // can serve it immediatly
+ XBT_INFO("CS idle. Grant immediatly");
+ if(strcmp(req, "1") == 0){
+ m_task_t answer = MSG_task_create("grant", 0, 1000, NULL);
+ MSG_task_send(answer, req);
+ CS_used = 1;
+ }else{
+ m_task_t answer = MSG_task_create("notgrant", 0, 1000, NULL);
+ MSG_task_send(answer, req);
+ }
+
+ }
+ } else { // that's a release. Check if someone was waiting for the lock
+ if (xbt_dynar_length(requests) > 0) {
+ XBT_INFO("CS release. Grant to queued requests (queue size: %lu)",
+ xbt_dynar_length(requests));
+ char *req;
+ if(strcmp(req, "1") == 0){
+ xbt_dynar_pop(requests, &req);
+ MSG_task_send(MSG_task_create("grant", 0, 1000, NULL), req);
+ todo--;
+ }else{
+ xbt_dynar_pop(requests, &req);
+ MSG_task_send(MSG_task_create("notgrant", 0, 1000, NULL), req);
+ todo--;
+ }
+ } else { // nobody wants it
+ XBT_INFO("CS release. resource now idle");
+ CS_used = 0;
+ todo--;
+ }
+ }
+ MSG_task_destroy(task);
+ }
+ XBT_INFO("Received all releases, quit now");
+ return 0;
+}
+
+int client(int argc, char *argv[])
+{
+ int my_pid = MSG_process_get_PID(MSG_process_self());
+ // use my pid as name of mailbox to contact me
+ char *my_mailbox = bprintf("%s", argv[1]);
+ // request the CS 2 times, sleeping a bit in between
+ int i;
+ for (i = 0; i < CS_PER_PROCESS; i++) {
+ p = 1;
+ q = 0;
+ XBT_INFO("Ask the request");
+ MSG_task_send(MSG_task_create("request", 0, 1000, my_mailbox),
+ "coordinator");
+ if(strcmp(my_mailbox, "1") == 0){
+ p = 1;
+ q = 0;
+ }
+ // wait the answer
+ m_task_t grant = NULL;
+ MSG_task_receive(&grant, my_mailbox);
+ const char *kind = MSG_task_get_name(grant);
+ if(!strcmp(kind, "grant")){
+ if(strcmp(my_mailbox, "2") == 0){
+ q = 1;
+ p = 0;
+ }
+ //answers ++;
+ MSG_task_destroy(grant);
+ XBT_INFO("got the answer. Sleep a bit and release it");
+ MSG_process_sleep(1);
+ MSG_task_send(MSG_task_create("release", 0, 1000,NULL ),
+ "coordinator");
+ }else{
+ MSG_task_destroy(grant);
+ XBT_INFO("Negative answer");
+ MSG_process_sleep(1);
+ MSG_task_send(MSG_task_create("notrelease", 0, 1000,NULL ),
+ "coordinator");
+ }
+
+ MSG_process_sleep(my_pid);
+
+ }
+
+ //XBT_INFO("Got all the CS I wanted (%s), quit now", my_mailbox);
+ return 0;
+}
+
+int main(int argc, char *argv[])
+{
+ init();
+ yyparse();
+ automaton = get_automaton();
+ xbt_propositional_symbol_t ps = xbt_new_propositional_symbol(automaton,"p", &predP);
+ ps = xbt_new_propositional_symbol(automaton,"q", &predQ);
+
+ MSG_global_init(&argc, argv);
+ MSG_create_environment("../msg_platform.xml");
+ MSG_function_register("coordinator", coordinator);
+ MSG_function_register("client", client);
+ MSG_launch_application("deploy_mutex2.xml");
+ MSG_main_liveness_stateless(automaton);
+ //MSG_main();
+
+ return 0;
+}
