amxb_ba_wait_for.c

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#include <syslog.h>
#include <stdlib.h>
#include <amxc/amxc.h>
#include <amxp/amxp.h>
 
#include <amxd/amxd_common.h>
#include <amxd/amxd_dm.h>
#include <amxd/amxd_object.h>
#include <amxd/amxd_object_event.h>
#include <amxd/amxd_path.h>
 
#include <amxb/amxb_be_intf.h>
#include <amxb/amxb.h>
 
#include "amxb_priv.h"
 
static int32_t wait_for_objects = 0;
 
static void amxb_wait_object_available(const char* const sig_name,
                                       UNUSED const amxc_var_t* const data,
                                       UNUSED void* const priv) {
    amxp_signal_t* signal = NULL;
    syslog(LOG_USER | LOG_NOTICE, "object '%s' available", sig_name + 5);
    signal = amxp_sigmngr_find_signal(NULL, sig_name);
    amxp_signal_delete(&signal);
 
    wait_for_objects--;
    if(wait_for_objects <= 0) {
        wait_for_objects = 0;
        amxp_sigmngr_emit_signal(NULL, "wait:done", NULL);
    }
}
 
static int amxb_wait_for_impl(amxb_bus_ctx_t* bus_ctx,
                              UNUSED const amxc_var_t* args,
                              void* priv) {
    int retval = 0;
    const amxb_be_funcs_t* fns = NULL;
    const char* object = (const char*) priv;
 
    fns = bus_ctx->bus_fn;
    if(amxb_is_valid_be_func(fns, wait_for, fns->wait_for)) {
        retval = fns->wait_for(bus_ctx->bus_ctx, object);
    } else {
        retval = AMXB_ERROR_NOT_SUPPORTED_OP;
    }
 
    return retval;
}
 
int amxb_wait_for_object(const char* object) {
    int retval = -1;
    amxd_path_t path;
    char* object_path = NULL;
    amxb_bus_ctx_t* bus_ctx = NULL;
    amxc_string_t signal_name;
    amxp_signal_t* signal = NULL;
 
    amxd_path_init(&path, NULL);
    amxc_string_init(&signal_name, 0);
 
    when_str_empty(object, exit);
 
    amxd_path_setf(&path, true, "%s", object);
    object_path = amxd_path_get_fixed_part(&path, AMXD_OBJECT_TERMINATE);
    amxc_string_setf(&signal_name, "wait:%s", object_path);
 
    signal = amxp_sigmngr_find_signal(NULL, amxc_string_get(&signal_name, 0));
    if(signal == NULL) {
        retval = amxp_signal_new(NULL, &signal, amxc_string_get(&signal_name, 0));
        when_failed(retval, exit);
        amxp_slot_connect(NULL, amxc_string_get(&signal_name, 0), NULL,
                          amxb_wait_object_available, NULL);
        wait_for_objects++;
    }
 
    // When waiting for an object, make sure that the exact full path is matched
    // remove entry from the cache and check again with full path matching
    // full path is the fixed part (no wildcard or search parts)
    amxb_be_cache_remove_path(object_path);
    bus_ctx = amxb_be_who_has_impl(object_path, true);
    if(bus_ctx != NULL) {
        amxp_signal_emit(signal, NULL);
        retval = 0;
    } else {
        retval = amxb_be_for_all_connections(amxb_wait_for_impl, NULL, (void*) object_path);
    }
 
exit:
    free(object_path);
    amxc_string_clean(&signal_name);
    amxd_path_clean(&path);
    return retval;
}