amxb_ubus_subscribe.c

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#include <stdlib.h>
 
#include "amxb_ubus.h"
 
static int amxb_ubus_receive_notification(struct ubus_context* ctx,
                                          AMXB_UNUSED struct ubus_object* obj,
                                          AMXB_UNUSED struct ubus_request_data* req,
                                          const char* method,
                                          struct blob_attr* msg) {
    int status = UBUS_STATUS_UNKNOWN_ERROR;
    struct ubus_subscriber* s = NULL;
    amxb_ubus_t* amxb_ubus_ctx = NULL;
    amxb_ubus_sub_t* amxb_ubus_sub = NULL;
    amxc_htable_t* subscribers = NULL;
    amxc_var_t notification;
    const char* subscriber_object = NULL;
 
    amxc_var_init(&notification);
    amxc_var_set_type(&notification, AMXC_VAR_ID_HTABLE);
 
    s = container_of(obj, struct ubus_subscriber, obj);
    amxb_ubus_sub = container_of(s, amxb_ubus_sub_t, sub);
    subscribers = container_of(amxb_ubus_sub->it.ait->array, amxc_htable_t, table);
    amxb_ubus_ctx = container_of(subscribers, amxb_ubus_t, subscribers);
 
    subscriber_object = amxc_htable_it_get_key(&amxb_ubus_sub->it);
    when_true(amxb_ubus_ctx->ubus_ctx != ctx, exit);
 
    amxb_ubus_parse_blob_table(&notification, (struct blob_attr*) blob_data(msg), blob_len(msg));
    amxc_var_add_key(cstring_t, &notification, "notification", method);
 
    amxp_sigmngr_emit_signal(amxb_ubus_ctx->sigmngr, subscriber_object, &notification);
 
    status = UBUS_STATUS_OK;
 
exit:
    amxc_var_clean(&notification);
    return status;
}
 
int PRIVATE amxb_ubus_subscribe(void* const ctx,
                                const char* object) {
    amxb_ubus_t* amxb_ubus_ctx = (amxb_ubus_t*) ctx;
    amxc_htable_it_t* it = NULL;
    amxb_ubus_sub_t* amxb_ubus_sub = NULL;
    amxc_string_t rel_path;
    amxd_path_t path;
    int ret = -1;
    uint32_t id = 0;
 
    amxc_string_init(&rel_path, 64);
    amxd_path_init(&path, NULL);
    amxd_path_setf(&path, true, "%s", object);
 
    when_failed(amxb_ubus_get_longest_path(amxb_ubus_ctx, &path, &rel_path), exit);
 
    ret = ubus_lookup_id(amxb_ubus_ctx->ubus_ctx, amxd_path_get(&path, 0), &id);
    when_true(ret != 0, exit);
 
    it = amxc_htable_get(&amxb_ubus_ctx->subscribers, amxd_path_get(&path, 0));
    when_not_null(it, exit);
 
    amxb_ubus_sub = (amxb_ubus_sub_t*) calloc(1, sizeof(amxb_ubus_sub_t));
    amxc_htable_insert(&amxb_ubus_ctx->subscribers,
                       object,
                       &amxb_ubus_sub->it);
 
    ret = ubus_register_subscriber(amxb_ubus_ctx->ubus_ctx,
                                   &amxb_ubus_sub->sub);
    when_true(ret != 0, exit);
    amxb_ubus_sub->sub.cb = amxb_ubus_receive_notification;
 
    ret = ubus_subscribe(amxb_ubus_ctx->ubus_ctx, &amxb_ubus_sub->sub, id);
 
exit:
    amxc_string_clean(&rel_path);
    amxd_path_clean(&path);
    return ret;
}
 
int PRIVATE amxb_ubus_unsubscribe(void* const ctx,
                                  const char* object) {
    amxb_ubus_t* amxb_ubus_ctx = (amxb_ubus_t*) ctx;
    amxb_ubus_sub_t* amxb_ubus_sub = NULL;
    amxc_htable_it_t* it = NULL;
    amxc_string_t rel_path;
    amxd_path_t path;
    int ret = 0;
    uint32_t id = 0;
 
    amxc_string_init(&rel_path, 64);
    amxd_path_init(&path, NULL);
    amxd_path_setf(&path, true, "%s", object);
 
    amxb_ubus_get_longest_path(amxb_ubus_ctx, &path, &rel_path);
 
    it = amxc_htable_get(&amxb_ubus_ctx->subscribers, object);
    when_null(it, leave);
    amxb_ubus_sub = amxc_htable_it_get_data(it, amxb_ubus_sub_t, it);
 
    ret = ubus_lookup_id(amxb_ubus_ctx->ubus_ctx, amxd_path_get(&path, 0), &id);
    when_true(ret != 0, exit);
 
    ubus_unsubscribe(amxb_ubus_ctx->ubus_ctx, &amxb_ubus_sub->sub, id);
 
exit:
    ret = ubus_unregister_subscriber(amxb_ubus_ctx->ubus_ctx, &amxb_ubus_sub->sub);
 
    amxc_htable_it_clean(it, NULL);
    amxp_timer_delete(&amxb_ubus_sub->reactivate);
    free(amxb_ubus_sub);
 
leave:
    amxc_string_clean(&rel_path);
    amxd_path_clean(&path);
 
    return ret;
}