amxrt_el_libevent.c

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#include <stdlib.h>
#include <string.h>
#include <signal.h>
 
#include <event2/event.h>
 
#include <amxrt/amxrt.h>
#include "amxrt_priv.h"
 
static struct event_base* base = NULL;
 
typedef struct _el_data {
    struct event* read;
    struct event* can_write;
    amxc_llist_it_t it;
} el_data_t;
 
static void amxrt_el_free_event_source(amxc_llist_it_t* it) {
    el_data_t* el_data = amxc_container_of(it, el_data_t, it);
    if(el_data->read != NULL) {
        event_del(el_data->read);
        free(el_data->read);
    }
    if(el_data->can_write != NULL) {
        event_del(el_data->can_write);
        free(el_data->can_write);
    }
 
    free(el_data);
}
 
static void amxrt_el_add_event_source(struct event* source, amxp_connection_t* con) {
    amxrt_t* rt = amxrt_get();
    el_data_t* el_data = (el_data_t*) calloc(1, sizeof(el_data_t));
    el_data->read = source;
    event_add(source, NULL);
 
    if(con != NULL) {
        con->el_data = el_data;
    }
 
    amxc_llist_append(&rt->event_sources, &el_data->it);
}
 
static void amxrt_el_signal_cb(UNUSED evutil_socket_t fd,
                               UNUSED short event,
                               UNUSED void* arg) {
    amxrt_el_stop();
}
 
static void amxrt_el_signal_timers(UNUSED evutil_socket_t fd,
                                   UNUSED short event,
                                   UNUSED void* arg) {
    amxp_timers_calculate();
    amxp_timers_check();
}
 
static void amxrt_el_connection_read_cb(UNUSED evutil_socket_t fd,
                                        UNUSED short flags,
                                        void* arg) {
    amxp_connection_t* con = (amxp_connection_t*) arg;
    con->reader(fd, con->priv);
}
 
static void amxrt_el_connection_can_write_cb(UNUSED evutil_socket_t fd,
                                             UNUSED short flags,
                                             void* arg) {
    amxp_connection_t* con = (amxp_connection_t*) arg;
    el_data_t* el_data = (el_data_t*) con->el_data;
    amxo_fd_cb_t cb = con->can_write;
 
    con->can_write = NULL;
    event_del(el_data->can_write);
    free(el_data->can_write);
    el_data->can_write = NULL;
 
    cb(fd, con->priv);
}
 
static void amxrt_el_amxp_signal_read_cb(UNUSED evutil_socket_t fd,
                                         UNUSED short flags,
                                         UNUSED void* arg) {
    amxp_signal_read();
}
 
static void amxrt_el_amxp_syssignal_read_cb(UNUSED evutil_socket_t fd,
                                            UNUSED short flags,
                                            UNUSED void* arg) {
    amxp_syssig_read();
}
 
static void amxrt_el_slot_add_fd(UNUSED const char* const sig_name,
                                 const amxc_var_t* const data,
                                 UNUSED void* const priv) {
    amxp_connection_t* con = NULL;
    struct event* source = NULL;
 
    when_true(amxc_var_type_of(data) != AMXC_VAR_ID_FD, leave);
 
    con = amxp_connection_get(amxc_var_constcast(fd_t, data));
    when_null(con, leave);
 
    source = event_new(base, con->fd, EV_READ | EV_PERSIST, amxrt_el_connection_read_cb, con);
    amxrt_el_add_event_source(source, con);
 
leave:
    return;
}
 
static void amxrt_el_slot_wait_write_fd(UNUSED const char* const sig_name,
                                        const amxc_var_t* const data,
                                        UNUSED void* const priv) {
    amxp_connection_t* con = NULL;
    el_data_t* el_data = NULL;
 
    when_true(amxc_var_type_of(data) != AMXC_VAR_ID_FD, leave);
 
    con = amxp_connection_get(amxc_var_constcast(fd_t, data));
    when_null(con, leave);
 
    el_data = (el_data_t*) con->el_data;
    when_null(el_data, leave);
    if(el_data->can_write != NULL) {
        event_del(el_data->can_write);
        free(el_data->can_write);
    }
    el_data->can_write = event_new(base,
                                   con->fd,
                                   EV_WRITE,
                                   amxrt_el_connection_can_write_cb,
                                   con);
    event_add(el_data->can_write, NULL);
 
leave:
    return;
}
 
static void amxrt_el_slot_remove_fd(UNUSED const char* const sig_name,
                                    const amxc_var_t* const data,
                                    UNUSED void* const priv) {
    amxc_llist_t* connections = amxp_connection_get_connections();
    amxp_connection_t* con = NULL;
 
    when_true(amxc_var_type_of(data) != AMXC_VAR_ID_FD, leave);
 
    con = amxrt_el_get_connection(connections, amxc_var_constcast(fd_t, data));
    if(con == NULL) {
        connections = amxp_connection_get_listeners();
        con = amxrt_el_get_connection(connections, amxc_var_constcast(fd_t, data));
    }
    when_null(con, leave);
 
    if(con->el_data != NULL) {
        el_data_t* el_data = (el_data_t*) con->el_data;
        if(el_data != NULL) {
            amxc_llist_it_clean(&el_data->it, amxrt_el_free_event_source);
        }
        con->el_data = NULL;
    }
 
leave:
    return;
}
 
static void amxrt_el_add_read_fd(amxc_llist_t* connections) {
    struct event* source = NULL;
 
    amxc_llist_for_each(it, connections) {
        amxp_connection_t* con = amxc_llist_it_get_data(it, amxp_connection_t, it);
        source = event_new(base, con->fd, EV_READ | EV_PERSIST, amxrt_el_connection_read_cb, con);
        amxrt_el_add_event_source(source, con);
    }
}
 
static void amxrt_el_remove_fd(amxc_llist_t* connections) {
    amxc_llist_for_each(it, connections) {
        amxp_connection_t* con = amxc_llist_it_get_data(it, amxp_connection_t, it);
        el_data_t* el_data = (el_data_t*) con->el_data;
        if(el_data != NULL) {
            amxc_llist_it_clean(&el_data->it, amxrt_el_free_event_source);
        }
        con->el_data = NULL;
    }
}
 
amxp_connection_t* amxrt_el_get_connection(amxc_llist_t* cons, int fd) {
    amxp_connection_t* con = NULL;
    amxc_llist_for_each(it, cons) {
        con = amxc_llist_it_get_data(it, amxp_connection_t, it);
        if(con->fd == fd) {
            break;
        }
        con = NULL;
    }
 
    return con;
}
 
int amxrt_el_create(void) {
    amxo_parser_t* parser = amxrt_get_parser();
    int retval = -1;
    struct event* event_source = NULL;
 
    base = event_base_new();
    when_null(base, leave);
 
    event_source = evsignal_new(base, SIGINT, amxrt_el_signal_cb, NULL);
    amxrt_el_add_event_source(event_source, NULL);
 
    event_source = evsignal_new(base, SIGTERM, amxrt_el_signal_cb, NULL);
    amxrt_el_add_event_source(event_source, NULL);
 
    event_source = evsignal_new(base, SIGALRM, amxrt_el_signal_timers, NULL);
    amxrt_el_add_event_source(event_source, NULL);
 
    event_source = event_new(base, amxp_signal_fd(), EV_READ | EV_PERSIST, amxrt_el_amxp_signal_read_cb, NULL);
    amxrt_el_add_event_source(event_source, NULL);
 
    event_source = event_new(base, amxp_syssig_get_fd(), EV_READ | EV_PERSIST, amxrt_el_amxp_syssignal_read_cb, NULL);
    amxrt_el_add_event_source(event_source, NULL);
 
    amxrt_el_add_read_fd(amxp_connection_get_connections());
    amxrt_el_add_read_fd(amxp_connection_get_listeners());
 
    amxp_slot_connect(NULL, "connection-added", NULL, amxrt_el_slot_add_fd, parser);
    amxp_slot_connect(NULL, "connection-wait-write", NULL, amxrt_el_slot_wait_write_fd, parser);
    amxp_slot_connect(NULL, "listen-added", NULL, amxrt_el_slot_add_fd, parser);
    amxp_slot_connect(NULL, "connection-deleted", NULL, amxrt_el_slot_remove_fd, parser);
    amxp_slot_connect(NULL, "listen-deleted", NULL, amxrt_el_slot_remove_fd, parser);
 
    retval = 0;
 
leave:
    return retval;
}
 
int amxrt_el_start(void) {
    int retval = -1;
    amxd_dm_t* dm = amxrt_get_dm();
 
    if(base != NULL) {
        retval = event_base_dispatch(base);
    }
 
    amxp_sigmngr_trigger_signal(&dm->sigmngr, "app:stop", NULL);
    amxp_sigmngr_trigger_signal(NULL, "wait:cancel", NULL);
 
    return retval;
}
 
int amxrt_el_stop(void) {
    int retval = -1;
    if(base != NULL) {
        retval = event_base_loopbreak(base);
    }
    return retval;
}
 
int amxrt_el_destroy(void) {
    amxrt_t* rt = amxrt_get();
 
    amxp_slot_disconnect(NULL, "connection-added", amxrt_el_slot_add_fd);
    amxp_slot_disconnect(NULL, "listen-added", amxrt_el_slot_add_fd);
    amxp_slot_disconnect(NULL, "connection-deleted", amxrt_el_slot_remove_fd);
 
    amxrt_el_remove_fd(amxp_connection_get_connections());
    amxrt_el_remove_fd(amxp_connection_get_listeners());
 
    amxc_llist_clean(&rt->event_sources, amxrt_el_free_event_source);
 
    if(base != NULL) {
        event_base_free(base);
        base = NULL;
    }
 
    return 0;
}