C++ sd_bus_reply_method_return函数代码示例

static int PmonInit(sd_bus_message *m, void *userdata, sd_bus_error *retError)
{
	usec_t time = 0;
	sd_bus_message_read(m, "t", &time);
	int id = 0;
	if (openSlots == 0) {
		return sd_bus_reply_method_return(m, "u", -1);
	}

	uint64_t usec = 0;
	sd_event_now(event, CLOCK_MONOTONIC, &usec);
	usec += time;
	if (clients[lastAllocatedId] == NULL) {
		id = lastAllocatedId;

		sd_event_add_time(event, &clients[lastAllocatedId], CLOCK_MONOTONIC, usec, 1000,
					Timeout, (void *)sd_bus_message_get_sender(m));
		lastAllocatedId += 1;
		openSlots -= 1;
		clientTimeout[id] = time;
		return sd_bus_reply_method_return(m, "u", id);
	}

	id = freeIds[lastFreedSlot];

	sd_event_add_time(event, &clients[freeIds[lastFreedSlot]], CLOCK_MONOTONIC, usec, 1000,
				Timeout, (void *)sd_bus_message_get_sender(m));

	lastFreedSlot -= 1;
	openSlots -= 1;
	clientTimeout[id] = time;
	return sd_bus_reply_method_return(m, "u", id);
}

static void server(sd_bus *b, size_t *result) {
        int r;

        for (;;) {
                _cleanup_bus_message_unref_ sd_bus_message *m = NULL;

                r = sd_bus_process(b, &m);
                assert_se(r >= 0);

                if (r == 0)
                        assert_se(sd_bus_wait(b, (usec_t) -1) >= 0);
                if (!m)
                        continue;

                if (sd_bus_message_is_method_call(m, "benchmark.server", "Ping"))
                        assert_se(sd_bus_reply_method_return(b, m, NULL) >= 0);
                else if (sd_bus_message_is_method_call(m, "benchmark.server", "Work")) {
                        const void *p;
                        size_t sz;

                        /* Make sure the mmap is mapped */
                        assert_se(sd_bus_message_read_array(m, 'y', &p, &sz) > 0);

                        assert_se(sd_bus_reply_method_return(b, m, NULL) >= 0);
                } else if (sd_bus_message_is_method_call(m, "benchmark.server", "Exit")) {
                        uint64_t res;
                        assert_se(sd_bus_message_read(m, "t", &res) > 0);

                        *result = res;
                        return;

                } else
                        assert_not_reached("Unknown method");
        }
}

static int generate_signals(sd_bus_message *m, void *userdata, sd_bus_error
        *ret_error) {
    uint64_t num_signals, payload_size;
    uint64_t i = 0;
    double c_time;
    int r;
    struct timeval ts;
    char *pl = NULL;

    /* Read the parameters */
    r = sd_bus_message_read(m, "tt", &num_signals, &payload_size);
    if (r < 0) {
        fprintf(stderr, "Failed to parse parameters: %s\n", strerror(-r));
        return r;
    }

    printf("SpamSignal: %"PRIu64", %"PRIu64 "\n", num_signals,
            payload_size);

    pl = (char*) malloc(payload_size + 1);
    _rs(pl, payload_size);

    for (i = 0; i < num_signals; i++) {
        c_time = time_time();
        r = sd_bus_emit_signal(bus, OBJ, INT,
                "Spam", "dts", c_time, payload_size, pl);
        if (r < 0) {
            fprintf(stderr, "Failed to emit signal: %s\n", strerror(-r));
            free(pl);
            return sd_bus_reply_method_return(m, "t", i);
        }
    }
    free(pl);
    return sd_bus_reply_method_return(m, "t", num_signals);
}

static int something_handler(sd_bus_message *m, void *userdata, sd_bus_error *error) {
        struct context *c = userdata;
        const char *s;
        char *n = NULL;
        int r;

        r = sd_bus_message_read(m, "s", &s);
        assert_se(r > 0);

        n = strjoin("<<<", s, ">>>", NULL);
        assert_se(n);

        free(c->something);
        c->something = n;

        log_info("AlterSomething() called, got %s, returning %s", s, n);

        /* This should fail, since the return type doesn't match */
        assert_se(sd_bus_reply_method_return(m, "u", 4711) == -ENOMSG);

        r = sd_bus_reply_method_return(m, "s", n);
        assert_se(r >= 0);

        return 1;
}

static int method_set_hostname(sd_bus_message *m, void *userdata, sd_bus_error *error) {
    Context *c = userdata;
    const char *name;
    int interactive;
    char *h;
    int r;

    assert(m);
    assert(c);

    r = sd_bus_message_read(m, "sb", &name, &interactive);
    if (r < 0)
        return r;

    if (isempty(name))
        name = c->data[PROP_STATIC_HOSTNAME];

    if (isempty(name))
        name = "localhost";

    if (!hostname_is_valid(name, false))
        return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid hostname '%s'", name);

    if (streq_ptr(name, c->data[PROP_HOSTNAME]))
        return sd_bus_reply_method_return(m, NULL);

    r = bus_verify_polkit_async(
            m,
            CAP_SYS_ADMIN,
            "org.freedesktop.hostname1.set-hostname",
            NULL,
            interactive,
            UID_INVALID,
            &c->polkit_registry,
            error);
    if (r < 0)
        return r;
    if (r == 0)
        return 1; /* No authorization for now, but the async polkit stuff will call us again when it has it */

    h = strdup(name);
    if (!h)
        return -ENOMEM;

    free(c->data[PROP_HOSTNAME]);
    c->data[PROP_HOSTNAME] = h;

    r = context_update_kernel_hostname(c);
    if (r < 0) {
        log_error_errno(r, "Failed to set host name: %m");
        return sd_bus_error_set_errnof(error, r, "Failed to set hostname: %s", strerror(-r));
    }

    log_info("Changed host name to '%s'", strna(c->data[PROP_HOSTNAME]));

    (void) sd_bus_emit_properties_changed(sd_bus_message_get_bus(m), "/org/freedesktop/hostname1", "org.freedesktop.hostname1", "Hostname", NULL);

    return sd_bus_reply_method_return(m, NULL);
}

int bus_scope_method_abandon(sd_bus_message *message, void *userdata, sd_bus_error *error) {
        Scope *s = userdata;
        int r;

        assert(message);
        assert(s);

        r = mac_selinux_unit_access_check(UNIT(s), message, "stop", error);
        if (r < 0)
                return r;

        r = bus_verify_manage_units_async(UNIT(s)->manager, message, error);
        if (r < 0)
                return r;
        if (r == 0)
                return 1; /* No authorization for now, but the async polkit stuff will call us again when it has it */

        r = scope_abandon(s);
        if (r == -ESTALE)
                return sd_bus_error_setf(error, BUS_ERROR_SCOPE_NOT_RUNNING, "Scope %s is not running, cannot abandon.", UNIT(s)->id);
        if (r < 0)
                return r;

        return sd_bus_reply_method_return(message, NULL);
}

int bus_job_method_cancel(sd_bus_message *message, void *userdata, sd_bus_error *error) {
        Job *j = userdata;
        int r;

        assert(message);
        assert(j);

        r = mac_selinux_unit_access_check(j->unit, message, "stop", error);
        if (r < 0)
                return r;

        /* Access is granted to the job owner */
        if (!sd_bus_track_contains(j->clients, sd_bus_message_get_sender(message))) {

                /* And for everybody else consult PolicyKit */
                r = bus_verify_manage_units_async(j->unit->manager, message, error);
                if (r < 0)
                        return r;
                if (r == 0)
                        return 1; /* No authorization for now, but the async polkit stuff will call us again when it has it */
        }

        job_finish_and_invalidate(j, JOB_CANCELED, true);

        return sd_bus_reply_method_return(message, NULL);
}

static int method_echo(sd_bus_message *m, void *userdata, sd_bus_error *ret_error) {
	char *str;
	const char *intf = sd_bus_message_get_interface(m),
	      *path = sd_bus_message_get_path(m);
	sd_bus *bus = sd_bus_message_get_bus(m);

	char response[512] = {0};
	int r;

	/* Read the parameters */
	r = sd_bus_message_read(m, "s", &str);
	if (r < 0) {
		fprintf(stderr, "Failed to parse parameters: %s\n", strerror(-r));
		return r;
	}

	r = sd_bus_emit_signal(bus, path, intf, "MethodInvoked", "ss",
			"Echo method was invoked", path);
	if (r < 0) {
		fprintf(stderr, "Failed to emit signal: %s\n", strerror(-r));
		return r;
	}

	strncat(response, path, 128);
	strcat(response, " says ");
	strncat(response, str, 128);

	/* Reply with the response */
	return sd_bus_reply_method_return(m, "s", &response);
}

int bus_image_method_remove(
                sd_bus_message *message,
                void *userdata,
                sd_bus_error *error) {

        Image *image = userdata;
        Manager *m = image->userdata;
        int r;

        assert(message);
        assert(image);

        r = bus_verify_polkit_async(
                        message,
                        CAP_SYS_ADMIN,
                        "org.freedesktop.machine1.manage-images",
                        false,
                        UID_INVALID,
                        &m->polkit_registry,
                        error);
        if (r < 0)
                return r;
        if (r == 0)
                return 1; /* Will call us back */

        r = image_remove(image);
        if (r < 0)
                return r;

        return sd_bus_reply_method_return(message, NULL);
}

int bus_machine_method_kill(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error) {
        Machine *m = userdata;
        const char *swho;
        int32_t signo;
        KillWho who;
        int r;

        assert(bus);
        assert(message);
        assert(m);

        r = sd_bus_message_read(message, "si", &swho, &signo);
        if (r < 0)
                return r;

        if (isempty(swho))
                who = KILL_ALL;
        else {
                who = kill_who_from_string(swho);
                if (who < 0)
                        return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid kill parameter '%s'", swho);
        }

        if (signo <= 0 || signo >= _NSIG)
                return sd_bus_error_setf(error, SD_BUS_ERROR_INVALID_ARGS, "Invalid signal %i", signo);

        r = machine_kill(m, who, signo);
        if (r < 0)
                return r;

        return sd_bus_reply_method_return(message, NULL);
}

static int operation_done(sd_event_source *s, const siginfo_t *si, void *userdata) {
        _cleanup_(sd_bus_error_free) sd_bus_error error = SD_BUS_ERROR_NULL;
        Operation *o = userdata;
        int r;

        assert(o);
        assert(si);

        log_debug("Operating " PID_FMT " is now complete with code=%s status=%i",
                  o->pid,
                  sigchld_code_to_string(si->si_code), si->si_status);

        o->pid = 0;

        if (si->si_code != CLD_EXITED) {
                r = sd_bus_error_setf(&error, SD_BUS_ERROR_FAILED, "Child died abnormally.");
                goto fail;
        }

        if (si->si_status == EXIT_SUCCESS)
                r = 0;
        else if (read(o->errno_fd, &r, sizeof(r)) != sizeof(r)) { /* Try to acquire error code for failed operation */
                r = sd_bus_error_setf(&error, SD_BUS_ERROR_FAILED, "Child failed.");
                goto fail;
        }

        if (o->done) {
                /* A completion routine is set for this operation, call it. */
                r = o->done(o, r, &error);
                if (r < 0) {
                        if (!sd_bus_error_is_set(&error))
                                sd_bus_error_set_errno(&error, r);

                        goto fail;
                }

        } else {
                /* The default operation when done is to simply return an error on failure or an empty success
                 * message on success. */
                if (r < 0) {
                        sd_bus_error_set_errno(&error, r);
                        goto fail;
                }

                r = sd_bus_reply_method_return(o->message, NULL);
                if (r < 0)
                        log_error_errno(r, "Failed to reply to message: %m");
        }

        operation_free(o);
        return 0;

fail:
        r = sd_bus_reply_method_error(o->message, &error);
        if (r < 0)
                log_error_errno(r, "Failed to reply to message: %m");

        operation_free(o);
        return 0;
}

int bus_machine_method_terminate(sd_bus_message *message, void *userdata, sd_bus_error *error) {
        Machine *m = userdata;
        int r;

        assert(message);
        assert(m);

        r = bus_verify_polkit_async(
                        message,
                        CAP_KILL,
                        "org.freedesktop.machine1.manage-machines",
                        NULL,
                        false,
                        UID_INVALID,
                        &m->manager->polkit_registry,
                        error);
        if (r < 0)
                return r;
        if (r == 0)
                return 1; /* Will call us back */

        r = machine_stop(m);
        if (r < 0)
                return r;

        return sd_bus_reply_method_return(message, NULL);
}

static int driver_remove_match(sd_bus *bus, sd_bus_message *message, void *userdata, sd_bus_error *error) {

        struct bus_match_component *components = NULL;
        _cleanup_free_ char *normalized = NULL;
        Context *context = userdata;
        unsigned n_components = 0;
        Client *c = NULL;
        Match *m = NULL;
        char *arg0;
        uint64_t id;
        int r;

        assert(bus);
        assert(message);
        assert(context);

        r = sd_bus_message_read(message, "s", &arg0);
        if (r < 0)
                return r;

        r = bus_kernel_parse_unique_name(message->sender, &id);
        if (r < 0)
                return r;

        c = hashmap_get(context->clients, &id);
        if (!c)
                return sd_bus_error_setf(error, SD_BUS_ERROR_MATCH_RULE_NOT_FOUND, "You have not registered any matches.");

        r = bus_match_parse(arg0, &components, &n_components);
        if (r < 0) {
                r = sd_bus_error_setf(error, SD_BUS_ERROR_MATCH_RULE_INVALID, "Match rule \"%s\" is not valid", arg0);
                goto finish;
        }

        normalized = bus_match_to_string(components, n_components);
        if (!normalized) {
                r = -ENOMEM;
                goto finish;
        }

        m = hashmap_get(c->matches, normalized);
        if (!m) {
                r = sd_bus_error_setf(error, SD_BUS_ERROR_MATCH_RULE_NOT_FOUND, "Match rule \"%s\" not found.", normalized);
                goto finish;
        }

        bus_remove_match_internal_kernel(bus, id, m->cookie);
        match_free(m);

        r = sd_bus_reply_method_return(message, NULL);

finish:
        bus_match_parse_free(components, n_components);

        if (c->n_matches <= 0)
                client_free(c);

        return r;
}

static int DevicePath(sd_bus_message *m, void *userdata, sd_bus_error *retError)
{
	int cmd = DBUSGETPATH;
	write(fd, &cmd, sizeof(int));
	read(fd, path, sizeof(path));

	return sd_bus_reply_method_return(m, "s", path);
}

static int GetTimeoutDbus(sd_bus_message *m, void *userdata, sd_bus_error *retError)
{
	int cmd = DBUSGETIMOUT;
	write(fd, &cmd, sizeof(long));
	read(fd, &timeout, sizeof(long));

	return sd_bus_reply_method_return(m, "x", timeout);
}