From 51724a36373bba46951b02c2c00dc5f4ed47dd22 Mon Sep 17 00:00:00 2001
From: zenon <kranklyboy1000@gmail.com>
Date: Thu, 7 Jun 2018 17:38:20 +0200
Subject: [PATCH] Proper closing and unlinking of semaphores and shared memory

---
 supervisor.c | 62 ++++++++++++++++++++++++++++++++++++++++++----------
 1 file changed, 50 insertions(+), 12 deletions(-)

diff --git a/supervisor.c b/supervisor.c
index 9a1e4be..23126c6 100644
--- a/supervisor.c
+++ b/supervisor.c
@@ -11,6 +11,12 @@ static const char *pname;
 
 struct circ_buf *shared;
 
+static int shmfd;
+
+static sem_t *sUsedSpace;
+
+static sem_t *sFreeSpace;
+
 struct sigaction sa;
 
 static int bestSolution[MAX_ITEMS];
@@ -40,19 +46,50 @@ void initCircBuf()
 
 void wait_sem(sem_t *sem)
 {
-	while (sem_wait(sem) == -1) { // interrupted by system call? 
-		printf("Interupted with error!\n"); //Just to check
+	while (sem_wait(sem) == -1) { // interrupted by syscall? 
 		if (errno == EINTR) {
-			if(quit == 1)
+			if (quit == 1) {
+				shared->quit = 1;
+				if (munmap(shared, sizeof(*shared)) == -1) {
+					perror("munmap");
+					exit(EXIT_FAILURE);
+				}
+				close(shmfd);
+				if (shm_unlink(SHM_NAME) == -1) {
+					perror("shm_unlink");
+					exit(EXIT_FAILURE);
+				}
+				sem_close(sUsedSpace);
+				sem_close(sFreeSpace);
+
+				sem_unlink(SEM_USED_SPACE);
+				sem_unlink(SEM_FREE_SPACE);
 				exit(EXIT_SUCCESS);
+			}
 			else continue;
 		}
+		shared->quit = 1;
+
+		if (munmap(shared, sizeof(*shared)) == -1) {
+			perror("munmap");
+			exit(EXIT_FAILURE);
+		}
+		close(shmfd);
+		if (shm_unlink(SHM_NAME) == -1) {
+			perror("shm_unlink");
+			exit(EXIT_FAILURE);
+		}
+		sem_close(sUsedSpace);
+		sem_close(sFreeSpace);
+
+		sem_unlink(SEM_USED_SPACE);
+		sem_unlink(SEM_FREE_SPACE);
 		exit(EXIT_FAILURE);
 	}
 	return;
 }
 
-void getSolution(sem_t sUsedSpace, sem_t sFreeSpace)
+void getSolution(sem_t *sUsedSpace, sem_t *sFreeSpace)
 {
 	int solution[MAX_ITEMS];
 	for (int i = 0; i < MAX_ITEMS; i++) {
@@ -60,16 +97,16 @@ void getSolution(sem_t sUsedSpace, sem_t sFreeSpace)
 	}
 
 	if (shared->head == -1) {
-		wait_sem(&sUsedSpace);
+		wait_sem(sUsedSpace);
 		shared->head = (shared->head + 1) % MAX_ITEMS;
-		sem_post(&sFreeSpace);
+		sem_post(sFreeSpace);
 	} else {
 		int i = 0;
 		while (shared->head != -1) {
-			wait_sem(&sUsedSpace);
+			wait_sem(sUsedSpace);
 			solution[i] = shared->head;
 			shared->head = (shared->head + 1) % MAX_ITEMS;
-			sem_post(&sFreeSpace);
+			sem_post(sFreeSpace);
 			i++;
 		}
 	}
@@ -126,7 +163,7 @@ int main(int argc, char *argv[])
 	sigaction(SIGINT, &sa, NULL);
 	sigaction(SIGTERM, &sa, NULL);
 
-	int shmfd = shm_open(SHM_NAME, O_RDWR | O_CREAT, PERMISSION);
+	shmfd = shm_open(SHM_NAME, O_RDWR | O_CREAT, PERMISSION);
 	if (shmfd == -1) {
 		perror(pname);
 		exit(EXIT_FAILURE);
@@ -142,13 +179,14 @@ int main(int argc, char *argv[])
 		exit(EXIT_FAILURE);
 	}
 
-	sem_t *sFreeSpace = sem_open(SEM_FREE_SPACE, O_CREAT | O_EXCL, PERMISSION, MAX_ITEMS);
-	sem_t *sUsedSpace = sem_open(SEM_USED_SPACE, O_CREAT | O_EXCL, PERMISSION, 0);
+	sFreeSpace = sem_open(SEM_FREE_SPACE, O_CREAT | O_EXCL, PERMISSION, MAX_ITEMS);
+	sUsedSpace = sem_open(SEM_USED_SPACE, O_CREAT | O_EXCL, PERMISSION, 0);
 
 	initCircBuf();
 
 	while (quit == 0) {
-		getSolution(*sUsedSpace, *sFreeSpace);
+		wait_sem(sUsedSpace);
+		getSolution(sUsedSpace, sFreeSpace);
 
 	}