X-Git-Url: http://info.iut-bm.univ-fcomte.fr/pub/gitweb/simgrid.git/blobdiff_plain/7641e1b61b13d593d2eb86fc7cbcb6c8bcb89d8d..e9b00bd03825b6b1c66e642886328ce6384d9dad:/examples/msg/mc/example_liveness_with_cycle.c

diff --git a/examples/msg/mc/example_liveness_with_cycle.c b/examples/msg/mc/example_liveness_with_cycle.c
new file mode 100644
index 0000000000..42ef27daa1
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+++ b/examples/msg/mc/example_liveness_with_cycle.c
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+/***************** 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;
+}