1 /***************** Centralized Mutual Exclusion Algorithm *********************/
2 /* This example implements a centralized mutual exclusion algorithm. */
3 /* CS requests of client 1 not satisfied */
4 /* LTL property checked : G(r->F(cs)); (r=request of CS, cs=CS ok) */
5 /******************************************************************************/
9 #include "xbt/automaton.h"
10 #include "bugged1_liveness.h"
12 #define AMOUNT_OF_CLIENTS 2
13 #define CS_PER_PROCESS 2
15 XBT_LOG_NEW_DEFAULT_CATEGORY(bugged1_liveness, "my log messages");
30 int coordinator(int argc, char *argv[])
32 xbt_dynar_t requests = xbt_dynar_new(sizeof(char *), NULL); // dynamic vector storing requests (which are char*)
33 int CS_used = 0; // initially the CS is idle
34 int todo = AMOUNT_OF_CLIENTS * CS_PER_PROCESS; // amount of releases we are expecting
37 MSG_task_receive(&task, "coordinator");
38 const char *kind = MSG_task_get_name(task); //is it a request or a release?
39 if (!strcmp(kind, "request")) { // that's a request
40 char *req = MSG_task_get_data(task);
41 if (CS_used) { // need to push the request in the vector
42 XBT_INFO("CS already used. Queue the request of client %d", atoi(req) +1);
43 xbt_dynar_push(requests, &req);
44 } else { // can serve it immediatly
45 if(strcmp(req, "2") == 0){
46 m_task_t answer = MSG_task_create("grant", 0, 1000, NULL);
47 MSG_task_send(answer, req);
49 XBT_INFO("CS idle. Grant immediatly");
52 } else { // that's a release. Check if someone was waiting for the lock
53 if (xbt_dynar_length(requests) > 0) {
54 XBT_INFO("CS release. Grant to queued requests (queue size: %lu)", xbt_dynar_length(requests));
56 xbt_dynar_get_cpy(requests, (xbt_dynar_length(requests) - 1), &req);
57 if(strcmp(req, "2") == 0){
58 xbt_dynar_pop(requests, &req);
59 MSG_task_send(MSG_task_create("grant", 0, 1000, NULL), req);
62 xbt_dynar_pop(requests, &req);
63 MSG_task_send(MSG_task_create("notgrant", 0, 1000, NULL), req);
67 } else { // nobody wants it
68 XBT_INFO("CS release. resource now idle");
73 MSG_task_destroy(task);
75 XBT_INFO("Received all releases, quit now");
79 int client(int argc, char *argv[])
81 int my_pid = MSG_process_get_PID(MSG_process_self());
83 char *my_mailbox = bprintf("%s", argv[1]);
86 // request the CS (CS_PER_PROCESS times), sleeping a bit in between
87 for (i = 0; i < CS_PER_PROCESS; i++) {
89 XBT_INFO("Ask the request");
90 MSG_task_send(MSG_task_create("request", 0, 1000, my_mailbox), "coordinator");
92 if(strcmp(my_mailbox, "1") == 0){
95 XBT_DEBUG("Propositions changed : r=1, cs=0");
99 m_task_t grant = NULL;
100 MSG_task_receive(&grant, my_mailbox);
101 const char *kind = MSG_task_get_name(grant);
103 if((strcmp(my_mailbox, "1") == 0) && (strcmp("grant", kind) == 0)){
106 XBT_DEBUG("Propositions changed : r=0, cs=1");
110 MSG_task_destroy(grant);
111 XBT_INFO("%s got the answer. Sleep a bit and release it", argv[1]);
112 MSG_process_sleep(1);
113 MSG_task_send(MSG_task_create("release", 0, 1000, NULL), "coordinator");
115 MSG_process_sleep(my_pid);
117 if(strcmp(my_mailbox, "1") == 0){
120 XBT_DEBUG("Propositions changed : r=0, cs=0");
125 XBT_INFO("Got all the CS I wanted (%s), quit now", my_mailbox);
129 int main(int argc, char *argv[])
131 xbt_automaton_t a = MC_create_automaton("promela1_bugged1_liveness");
132 xbt_new_propositional_symbol(a,"r", &predR);
133 xbt_new_propositional_symbol(a,"cs", &predCS);
135 MSG_global_init(&argc, argv);
136 MSG_create_environment("../msg_platform.xml");
137 MSG_function_register("coordinator", coordinator);
138 MSG_function_register("client", client);
139 MSG_launch_application("deploy_bugged1_liveness.xml");
140 MSG_main_liveness(a);