From b1c3c5ca4ac63d8e7f92cc130a75d2322b8a28d8 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Rafa=C5=82=20D=C5=82ugo=C5=82=C4=99cki?=
 <rafal@dlugolecki.net.pl>
Date: Sat, 21 Jun 2014 12:38:00 +0200
Subject: [PATCH] Initial message queue communication.

---
 src/process1.c | 37 ++++++++++++++++++++++++++++++++++++-
 src/process2.c | 36 +++++++++++++++++++++++++++++++++++-
 src/process3.c | 36 +++++++++++++++++++++++++++++++++++-
 3 files changed, 106 insertions(+), 3 deletions(-)

diff --git a/src/process1.c b/src/process1.c
index b28563f..41e0ea4 100644
--- a/src/process1.c
+++ b/src/process1.c
@@ -46,6 +46,19 @@ struct message {
 
 struct message * processes = NULL;
 
+/**
+ * Message queue variables
+ */
+key_t qkey;
+int qid_input;
+
+int qid_output1;
+int qid_output2;
+
+struct queue_message {
+	int signo;
+};
+
 /**
  * Handler for signals.
  */
@@ -53,9 +66,13 @@ void sig_handler(int signo)
 {
 	fprintf(stderr, "[%s] Received %s!\n", "process1", strsignal(signo));
 	if (signo == SIGUSR1) {
+		fprintf(stderr, "[%s] > Notified!\n", "process3");
 	}
 	else if (signo == SIGTERM) {
 		int i = 0;
+		struct queue_message msg;
+		msg.signo = signo;
+
 		fprintf(stderr, "[%s] > Releasing resources\n", "process1");
 		close(write_pipe);
 		unlink(write_pipe);
@@ -65,7 +82,13 @@ void sig_handler(int signo)
 			buffer = NULL;
 		}
 		for (; i < 3; i++) {
-			fprintf(stderr, "[%s] Process %d, PID: %d\n", "process3", i, processes->pids[i]);
+			pid_t pid = processes->pids[i];
+			fprintf(stderr, "[%s] Process %d, PID: %d\n", "process3", i, pid);
+			// Bleh
+			if (i != 0) {
+				msgsnd(pid, &msg, sizeof(msg));
+				kill(pid, SIGUSR1);
+			}
 		}
 		exit(0);
 	}
@@ -127,6 +150,18 @@ int main(void) {
 	processes = (struct message *)shmat(shmid, NULL, 0);
 	processes->pids[0] = getpid();
 
+	fprintf(stderr, "[%s] Shared pid: %d\n", "process1", 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);
+	
 	mkfifo(write_pipe, 0666);
 
 	file_descriptor = open(write_pipe, O_WRONLY);
diff --git a/src/process2.c b/src/process2.c
index 2417fe8..d8c294b 100644
--- a/src/process2.c
+++ b/src/process2.c
@@ -49,6 +49,18 @@ struct message {
 
 struct message * processes = NULL;
 
+/**
+ * Message queue variables
+ */
+key_t qkey;
+int qid_input;
+
+int qid_output1;
+int qid_output2;
+
+struct queue_message {
+	int signo;
+};
 
 /**
  * Handler for signals.
@@ -57,15 +69,25 @@ void sig_handler(int signo)
 {
 	fprintf(stderr, "[%s] Received %s!\n", "process2", strsignal(signo));
 	if (signo == SIGUSR1) {
+		fprintf(stderr, "[%s] > Notified!\n", "process2");
 	}
 	else if (signo == SIGTERM) {
 		int i = 0;
+		struct queue_message msg;
+		msg.signo = signo;
+
 		fprintf(stderr, "[%s] > Releasing resources\n", "process2");
 		close(read_descriptor);
 		close(write_descriptor);
 		unlink(write_descriptor);
 		for (; i < 3; i++) {
-			fprintf(stderr, "[%s] Process %d, PID: %d\n", "process3", i, processes->pids[i]);
+			pid_t pid = processes->pids[i];
+			fprintf(stderr, "[%s] Process %d, PID: %d\n", "process2", i, pid);
+			// Bleh
+			if (i != 1) {
+				msgsnd(pid, &msg, sizeof(msg));
+				kill(pid, SIGUSR1);
+			}
 		}
 		exit(0);
 	}
@@ -130,6 +152,18 @@ int main(void) {
 	processes = (struct message *)shmat(shmid, NULL, 0);
 	processes->pids[1] = getpid();
 
+	fprintf(stderr, "[%s] Shared pid: %d\n", "process2", 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);
+
 	/* Reading from process1 */
 	read_descriptor = open(read_pipe, O_RDONLY);
 
diff --git a/src/process3.c b/src/process3.c
index b1b9972..54bb658 100644
--- a/src/process3.c
+++ b/src/process3.c
@@ -40,6 +40,18 @@ struct message {
 
 struct message * processes = NULL;
 
+/**
+ * Message queue variables
+ */
+key_t qkey;
+int qid_input;
+
+int qid_output1;
+int qid_output2;
+
+struct queue_message {
+	int signo;
+};
 
 /**
  * Handler for signals.
@@ -48,13 +60,23 @@ void sig_handler(int signo)
 {
 	fprintf(stderr, "[%s] Received %s!\n", "process3", strsignal(signo));
 	if (signo == SIGUSR1) {
+		fprintf(stderr, "[%s] > Notified!\n", "process3");
 	}
 	else if (signo == SIGTERM) {
 		int i = 0;
+		struct queue_message msg;
+		msg.signo = signo;
+
 		fprintf(stderr, "[%s] > Releasing resources\n", "process3");
 		close(read_descriptor);
 		for (; i < 3; i++) {
-			fprintf(stderr, "[%s] Process %d, PID: %d\n", "process3", i, processes->pids[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);
 	}
@@ -107,6 +129,18 @@ int main(void) {
 	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);
+
 	/* Reading from process2 */
 	read_descriptor = open(read_pipe, O_RDONLY);
 
-- 
2.30.2