unix/fb_arc_set/shared/structs.c

#include <stdbool.h> ///< For boolean constants
#include <signal.h>

#define BUFF_SIZE 8
#define SET_MAX_SIZE 8

/// Struct for the edge
typedef struct edge {
    bool chosen;
    int u, v;
} edge_t;

/// Struct for the feedback arc set
typedef struct fb_arc_set {
    bool valid;
    int edge_num;
    edge_t edges[SET_MAX_SIZE];
} fb_arc_set_t;

/// Struct for the circular buffer
typedef struct buffer {
    bool finished;
    short best_arc_len;
    fb_arc_set_t sets[BUFF_SIZE];
} buffer_t;

static bool terminate = false;
static int buffer_shmfd;
static buffer_t *circ_buffer;

/**
 * @brief Function to execute when the program gets a signal
 * @details Flips the terminate variable to true
 * @param signo
 * @return none
 **/
static void signal_handler(int signo) {
    terminate = true;
}

/**
 * @brief Function to process the signals passed by the user
 * @details Creates a new sigaction structure
 *          and changes the behaviour of the SIGINT and SIGTERM signals
 * @param none
 * @return none
 **/
static void process_signal(void){
    struct sigaction sa;
    memset(&sa, 0, sizeof(sa));
    sa.sa_handler = signal_handler;
    sigaction(SIGINT, &sa, NULL);
    sigaction(SIGTERM, &sa, NULL);
}

/**
 * @brief Function to that cleans up the resources
 * @details The function closes and destroys all semaphores,
 *          closes and destroys all shared memory objects and
 *          closes the file descriptors
 * @param none
 * @return none
 **/
static void clean_up(void) {
    /// Close and destory semaphores
    close_sem(free_sem);
    close_sem(use_sem);
    close_sem(mutex);

    destroy_sem(FREE_SEM_NAME);
    destroy_sem(USE_SEM_NAME);
    destroy_sem(MUTEX_NAME);

    /// Close and destroy shared memory objects
    close_shm(circ_buffer, sizeof(buffer_t));
    destroy_shm(BUFF_SHM_NAME, buffer_shmfd);
}