X-Git-Url: https://git.dlugolecki.net.pl/?a=blobdiff_plain;ds=sidebyside;f=src%2Fprocess3.c;h=91212e991a1cc3ff0363e1a8f157fa5df5a7bc8b;hb=761a17f0fa43527cec843a4fa95ec7cf7ad2d476;hp=54bb6587370a53648f0aecbc63a6e2b299ec5176;hpb=b1c3c5ca4ac63d8e7f92cc130a75d2322b8a28d8;p=wsti_so.git

diff --git a/src/process3.c b/src/process3.c
index 54bb658..91212e9 100644
--- a/src/process3.c
+++ b/src/process3.c
@@ -2,6 +2,8 @@
 
 /* exit.. */
 #include <stdlib.h>
+/* strsignal... */
+#include <string.h>
 
 /* open/read/write/close */
 #include <fcntl.h>
@@ -10,6 +12,7 @@
 #include <signal.h>
 
 #include <sys/shm.h>
+#include <sys/msg.h>
 
 /** Named pipe used to communicate with process2 */
 char * read_pipe = "/tmp/process2pipe";
@@ -32,7 +35,8 @@ key_t shmkey = 18912;
 int shmid;
 
 /**
- * Message shared by processes. Contains array of process IDs
+ * Structure holding array of process IDs.
+ * Message is shared by processes. Contains array of process IDs
  */
 struct message {
 	pid_t pids[3];
@@ -41,51 +45,83 @@ struct message {
 struct message * processes = NULL;
 
 /**
- * Message queue variables
+ * Message Queue variables
  */
-key_t qkey;
-int qid_input;
 
-int qid_output1;
-int qid_output2;
+/**
+ * Unique key of message queue.
+ */
+key_t qkey = 12356;
+
+/**
+ * Queue descriptor.
+ */
+int qid;
 
+/**
+ * Structure holding queue message data.
+ * Parameter mtype describes process to whom message is sent.
+ * Parameter signo is a signal to raise after getting message.
+ */
 struct queue_message {
-	int signo;
+	long mtype;
+	int signo[1];
 };
 
+void notify_other_processes(int signo) {
+	int i = 0;
+	struct queue_message msg;
+ 	msg.signo[0] = signo;
+
+	for (; i < 3; i++) {
+		pid_t pid = processes->pids[i];
+		// Bleh
+		if (i != 2 && pid != 0) {
+			msg.mtype = i+1;
+			fprintf(stderr, "[%s] Sending message of type (%d) with value %d\n", "process3", msg.mtype, msg.signo[0]);
+			msgsnd(qid, &msg, sizeof(int), 0);
+			fprintf(stderr, "[%s] Sending signal %s (%d) to PID: %d\n", "process3", strsignal(SIGUSR1), SIGUSR1, pid);
+			kill(pid, SIGUSR1);
+		}
+	}
+}
+
 /**
  * Handler for signals.
  */
 void sig_handler(int signo)
 {
-	fprintf(stderr, "[%s] Received %s!\n", "process3", strsignal(signo));
+ 	fprintf(stderr, "[%s] Received %s!\n", "process3", strsignal(signo));
 	if (signo == SIGUSR1) {
 		fprintf(stderr, "[%s] > Notified!\n", "process3");
+		struct queue_message msg;
+		/* Check queues from both other processes */
+		if (msgrcv(qid, &msg, sizeof(int), 3, 0) > 0) {
+			fprintf(stderr, "[%s] > Notified with value: %s!\n", "process3", strsignal(msg.signo[0]));
+			raise(msg.signo[0]);
+		}
 	}
 	else if (signo == SIGTERM) {
-		int i = 0;
-		struct queue_message msg;
-		msg.signo = signo;
+		fprintf(stderr, "[%s] > Signalling other processes..\n", "process3");
+		processes->pids[2] = 0;
+		notify_other_processes(signo);
 
 		fprintf(stderr, "[%s] > Releasing resources\n", "process3");
 		close(read_descriptor);
-		for (; i < 3; i++) {
-			pid_t pid = processes->pids[i];
-			fprintf(stderr, "[%s] Process %d, PID: %d\n", "process3", i, pid);
-			// Bleh
-			if (i != 2) {
-				msgsnd(pid, &msg, sizeof(msg));
-				kill(pid, SIGUSR1);
-			}
-		}
 		exit(0);
 	}
 	else if (signo == SIGTSTP) {
+		fprintf(stderr, "[%s] > Signalling other processes..\n", "process3");
+		notify_other_processes(signo);
+
 		fprintf(stderr, "[%s] > Closing pipe\n", "process3");
 		close(read_descriptor);
 		raise (SIGSTOP);
 	}
 	else if (signo == SIGCONT) {
+		fprintf(stderr, "[%s] > Signalling other processes..\n", "process3");
+		notify_other_processes(signo);
+
 		fprintf(stderr, "[%s] > Opening pipe\n", "process3");
 		read_descriptor = open(read_pipe, O_RDONLY);
 	}
@@ -124,22 +160,17 @@ int main(void) {
 	 * Register memory to share with other processes, and pass current
 	 * process id to the array.
 	 */
-	shmid = shmget(shmkey, sizeof(struct message), IPC_CREAT | 0666);
+	shmid = shmget(shmkey, sizeof(struct message), 0666);
 
 	processes = (struct message *)shmat(shmid, NULL, 0);
 	processes->pids[2] = getpid();
 
 	fprintf(stderr, "[%s] Shared pid: %d\n", "process3", getpid());
 
-	sleep(1);
 	/**
 	 * Register message queue to communicate with other processes
 	 */
-	qkey = getpid();
-	qid_input = msgget(qkey, IPC_CREAT | 0666);
-	
-	qid_output1 = msgget(processes->pids[1], IPC_CREAT | 0666);
-	qid_output2 = msgget(processes->pids[2], IPC_CREAT | 0666);
+	qid = msgget(qkey, 0666);
 
 	/* Reading from process2 */
 	read_descriptor = open(read_pipe, O_RDONLY);