Add semaphore functions implementations

fb_arc_set/Makefile

@@ -5,16 +5,16 @@ TARGET_2 = supervisor
 
 all: $(TARGET_1).c $(TARGET_2).c
 	$(CC) $(CFLAGS) $(TARGET_1).c $(TARGET_2).c
-	$(CC) $(TARGET_1).o -o $(TARGET_1) -lrt
-	$(CC) $(TARGET_2).o -o $(TARGET_2) -lrt
+	$(CC) $(TARGET_1).o -o $(TARGET_1) -lrt -lpthread
+	$(CC) $(TARGET_2).o -o $(TARGET_2) -lrt -lpthread
 
 generator: $(TARGET_1).c
 	$(CC) $(CFLAGS) $(TARGET_1).c
-	$(CC) $(TARGET_1).o -o $(TARGET_1) -lrt
+	$(CC) $(TARGET_1).o -o $(TARGET_1) -lrt -lpthread
 
 supervisor: $(TARGET_2).c
 	$(CC) $(CFLAGS) $(TARGET_2).c
-	$(CC) $(TARGET_2).o -o $(TARGET_2) -lrt
+	$(CC) $(TARGET_2).o -o $(TARGET_2) -lrt -lpthread
 
 install:
 	cp $(TARGET_1) /usr/local/bin/graph-$(TARGET_1)

fb_arc_set/generator.c

@@ -27,6 +27,8 @@
  *
  **/
 #include "shared/shm.c"
+#include "shared/sem.c"
+#include "shared/structs.c"
 #include <regex.h>
 
 int main(int argc, char *argv[]) {
@@ -36,25 +38,33 @@ int main(int argc, char *argv[]) {
         exit(EXIT_FAILURE);
     }
 
+    /// Create a regex to check the input against
     regex_t regex;
     if(regcomp(&regex, "^[0-9]*-[0-9]*$", REG_EXTENDED|REG_NOSUB)) {
         fprintf(stderr, "ERROR: Could not compile regex\n");
         exit(EXIT_FAILURE);
     }
 
-    for(int i=1; i <= argc - 1; i++) {
+    edge_t edges[argc - 2]; ///< Array to hold the edges
+
+    char edge[128]; ///< Variable to hold a single edge later on
+    edge[127] = 0;
+
+    for(int i=1; i < argc; i++) {
+        /// Check the input and terminate if incorrect
         if(regexec(&regex, argv[i], 0, NULL, 0) == REG_NOMATCH) {
             fprintf(stderr, "ERROR: Incorrect input found\n");
             puts("Usage: \ngenerator EDGE1 EDGE2 ...");
             exit(EXIT_FAILURE);
+        } else {
+            /// If input is correct, split and add to the edges array
+            strcpy(edge, argv[i]);
+            char *u = strtok(edge, "-");
+            char *v = strtok(NULL, "");
+            edges[i-1].u = strtol(u, NULL, 10);
+            edges[i-1].v = strtol(v, NULL, 10);
         }
     }
 
-    void* terminate_shm = open_shm(TERMINATE_SHM, TERMINATE_SHM_SIZE);
-
-    write_to_shm(terminate_shm, "1", TERMINATE_SHM_SIZE);
-    puts(terminate_shm);
-    close_shm(terminate_shm, TERMINATE_SHM_SIZE);
-    destroy_shm(TERMINATE_SHM);
+    exit(EXIT_SUCCESS);
 }
-

fb_arc_set/shared/sem.c

@@ -0,0 +1,41 @@
+#ifndef LIBRARIES
+#define LIBRARIES
+#define _GNU_SOURCE
+#include <fcntl.h> ///< For O_* constants *
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+#endif
+
+#include <semaphore.h> ///< For semaphores
+
+#define FREE_SEM_NAME "/11777707_free"
+#define USED_SEM_NAME "/11777707_used"
+#define MUTEX_NAME "/11777707_mutex"
+
+static sem_t *free_sem;
+static sem_t *used_sem;
+static sem_t *mutex;
+
+sem_t * open_sem(char *sem_name, size_t sem_size) {
+    sem_t *res = sem_open(sem_name, O_CREAT | O_EXCL, 0600, sem_size);
+    if(res == SEM_FAILED) {
+        fprintf(stderr, "ERROR: Failed opening semaphore\n");
+        exit(EXIT_FAILURE);
+    }
+    return res;
+}
+
+void close_sem(sem_t *sem) {
+    if(sem_close(sem) < 0) {
+        fprintf(stderr, "ERROR: Failed closing semaphore\n");
+        exit(EXIT_FAILURE);
+    }
+}
+
+void destroy_sem(char *sem_name) {
+    if(sem_unlink(sem_name) < 0) {
+        fprintf(stderr, "ERROR: Failed closing semaphore\n");
+        exit(EXIT_FAILURE);
+    }
+}

fb_arc_set/shared/shm.c

@@ -1,22 +1,28 @@
+#ifndef LIBRARIES
+#define LIBRARIES
 #define _GNU_SOURCE
-#include <fcntl.h>
+#include <fcntl.h> ///< For O_* constants *
 #include <stdlib.h>
 #include <stdio.h>
+#include <unistd.h>
+#endif
+
+#include <string.h>
 #include <sys/mman.h>
 #include <sys/types.h>
-#include <unistd.h>
-#include <string.h>
 
-#define TERMINATE_SHM "/terminate"
-#define TERMINATE_SHM_SIZE 8
+#define BUFFER_SHM_NAME "/11777707_buff"
 
-void* open_shm(char *shm_name, size_t shm_size) {
+int create_shmfd(char *shm_name) {
     int shmfd = shm_open(shm_name, O_RDWR | O_CREAT, 0600);
     if(shmfd == -1) {
         fprintf(stderr, "ERROR: Failed creating shared memory object\n");
         exit(EXIT_FAILURE);
     }
+    return shmfd;
+}
 
+void* open_shm(int shmfd, size_t shm_size) {
     if(ftruncate(shmfd, shm_size) < 0) {
         fprintf(stderr, "ERROR: Failed truncating shared memory object\n");
         exit(EXIT_FAILURE);
@@ -44,9 +50,13 @@ void close_shm(void* shm, size_t shm_size) {
     }
 }
 
-void destroy_shm(char *shm_name) {
+void destroy_shm(char *shm_name, int shmfd) {
     if (shm_unlink(shm_name) == -1) {
         fprintf(stderr, "ERROR: Failed unlinking shared memory object\n");
         exit(EXIT_FAILURE);
     }
+    if(close(shmfd) < 0) {
+        fprintf(stderr, "ERROR: Failed closing file descriptor\n");
+        exit(EXIT_FAILURE);
+    }
 }

fb_arc_set/shared/structs.c

@@ -0,0 +1,23 @@
+#include <stdbool.h> ///< For boolean constants
+
+#define BUFF_SIZE 8
+#define SET_MAX_SIZE 8
+
+/// Struct for the edge
+typedef struct edge {
+    int u, v;
+} edge_t;
+
+/// Struct for the feedback arc set
+typedef struct fb_set {
+    bool valid;
+    edge_t edges[SET_MAX_SIZE];
+} fb_set_t;
+
+/// Struct for the circular buffer
+typedef struct buffer {
+    bool terminate;
+    fb_set_t sets[BUFF_SIZE];
+} buffer_t;
+
+static buffer_t *circ_buffer;

fb_arc_set/supervisor.c

@@ -22,6 +22,8 @@
  *
  **/
 #include "shared/shm.c"
+#include "shared/sem.c"
+#include "shared/structs.c"
 
 int main(int argc, char *argv[]) {
     if(argc > 1) {
@@ -29,9 +31,26 @@ int main(int argc, char *argv[]) {
         exit(EXIT_FAILURE);
     }
 
-    void* terminate_shm = open_shm(TERMINATE_SHM, TERMINATE_SHM_SIZE);
+    /// Open shared memory objects
+    int buffer_shmfd = create_shmfd(BUFFER_SHM_NAME);
+    circ_buffer = (buffer_t *)open_shm(buffer_shmfd, sizeof(buffer_t));
 
-    write_to_shm(terminate_shm, "1", TERMINATE_SHM_SIZE);
-    close_shm(terminate_shm, TERMINATE_SHM_SIZE);
-    destroy_shm(TERMINATE_SHM);
+    /// Open semaphores
+    free_sem = open_sem(FREE_SEM_NAME, BUFF_SIZE);
+    used_sem = open_sem(USED_SEM_NAME, 0);
+    mutex = open_sem(MUTEX_NAME, 1);
+
+
+    /// Close and destory semaphores
+    close_sem(free_sem);
+    close_sem(used_sem);
+    close_sem(mutex);
+
+    destroy_sem(FREE_SEM_NAME);
+    destroy_sem(USED_SEM_NAME);
+    destroy_sem(MUTEX_NAME);
+
+    /// Close and destroy shared memory objects
+    close_shm(circ_buffer, sizeof(buffer_t));
+    destroy_shm(BUFFER_SHM_NAME, buffer_shmfd);
 }