C++ sd_bus_message_enter_container函数代码示例

static int count_addresses(sd_bus_message *m, int af, const char **canonical) {
        int c = 0, r, ifindex;

        assert(m);
        assert(canonical);

        r = sd_bus_message_read(m, "i", &ifindex);
        if (r < 0)
                return r;

        r = sd_bus_message_enter_container(m, 'a', "(iay)");
        if (r < 0)
                return r;

        while ((r = sd_bus_message_enter_container(m, 'r', "iay")) > 0) {
                int family;

                r = sd_bus_message_read(m, "i", &family);
                if (r < 0)
                        return r;

                r = sd_bus_message_skip(m, "ay");
                if (r < 0)
                        return r;

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

                if (af != AF_UNSPEC && family != af)
                        continue;

                c ++;
        }
        if (r < 0)
                return r;

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

        r = sd_bus_message_read(m, "s", canonical);
        if (r < 0)
                return r;

        r = sd_bus_message_rewind(m, true);
        if (r < 0)
                return r;

        return c;
}

_public_ int sd_bus_get_property_strv(
                sd_bus *bus,
                const char *destination,
                const char *path,
                const char *interface,
                const char *member,
                sd_bus_error *error,
                char ***ret) {

        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
        int r;

        assert_return(bus, -EINVAL);
        assert_return(isempty(interface) || interface_name_is_valid(interface), -EINVAL);
        assert_return(member_name_is_valid(member), -EINVAL);
        assert_return(ret, -EINVAL);
        assert_return(!bus_pid_changed(bus), -ECHILD);

        if (!BUS_IS_OPEN(bus->state))
                return -ENOTCONN;

        r = sd_bus_call_method(bus, destination, path, "org.freedesktop.DBus.Properties", "Get", error, &reply, "ss", strempty(interface), member);
        if (r < 0)
                return r;

        r = sd_bus_message_enter_container(reply, 'v', NULL);
        if (r < 0)
                return r;

        r = sd_bus_message_read_strv(reply, ret);
        if (r < 0)
                return r;

        return 0;
}

static int kbdctx_set_locale(sd_bus *bus, const char *member, sd_bus_message *m, sd_bus_error *error, void *userdata) {
        kbdctx *kc = userdata;
        const char *s, *ctype = NULL, *lang = NULL;
        int r;

        r = sd_bus_message_enter_container(m, 'a', "s");
        if (r < 0)
                goto error;

        while ((r = sd_bus_message_read(m, "s", &s)) > 0) {
                if (!ctype)
                        ctype = startswith(s, "LC_CTYPE=");
                if (!lang)
                        lang = startswith(s, "LANG=");
        }

        if (r < 0)
                goto error;

        r = sd_bus_message_exit_container(m);
        if (r < 0)
                goto error;

        kbdctx_refresh_compose_table(kc, ctype ? : lang);
        r = 0;

error:
        if (r < 0)
                log_debug_errno(r, "idev-keyboard: cannot parse locale property from locale1: %m");

        return r;
}

_public_ int sd_bus_get_property_trivial(
                sd_bus *bus,
                const char *destination,
                const char *path,
                const char *interface,
                const char *member,
                sd_bus_error *error,
                char type, void *ptr) {

        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
        int r;

        assert_return(bus, -EINVAL);
        assert_return(isempty(interface) || interface_name_is_valid(interface), -EINVAL);
        assert_return(member_name_is_valid(member), -EINVAL);
        assert_return(bus_type_is_trivial(type), -EINVAL);
        assert_return(ptr, -EINVAL);
        assert_return(BUS_IS_OPEN(bus->state), -ENOTCONN);
        assert_return(!bus_pid_changed(bus), -ECHILD);

        r = sd_bus_call_method(bus, destination, path, "org.freedesktop.DBus.Properties", "Get", error, &reply, "ss", strempty(interface), member);
        if (r < 0)
                return r;

        r = sd_bus_message_enter_container(reply, 'v', CHAR_TO_STR(type));
        if (r < 0)
                return r;

        r = sd_bus_message_read_basic(reply, type, ptr);
        if (r < 0)
                return r;

        return 0;
}

static void print_inhibitors(sd_bus *bus) {
        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
        const char *what, *who, *why, *mode;
        uint32_t uid, pid;
        unsigned n = 0;
        int r;

        r = sd_bus_call_method(bus,
                        "org.freedesktop.login1",
                        "/org/freedesktop/login1",
                        "org.freedesktop.login1.Manager",
                        "ListInhibitors",
                        &error,
                        &reply,
                        "");
        assert_se(r >= 0);

        r = sd_bus_message_enter_container(reply, SD_BUS_TYPE_ARRAY, "(ssssuu)");
        assert_se(r >= 0);

        while ((r = sd_bus_message_read(reply, "(ssssuu)", &what, &who, &why, &mode, &uid, &pid)) > 0) {
                printf("what=<%s> who=<%s> why=<%s> mode=<%s> uid=<%"PRIu32"> pid=<%"PRIu32">\n",
                       what, who, why, mode, uid, pid);

                n++;
        }
        assert_se(r >= 0);

        printf("%u inhibitors\n", n);
}

_public_ int sd_bus_get_property(
                sd_bus *bus,
                const char *destination,
                const char *path,
                const char *interface,
                const char *member,
                sd_bus_error *error,
                sd_bus_message **reply,
                const char *type) {

        sd_bus_message *rep = NULL;
        int r;

        assert_return(bus, -EINVAL);
        assert_return(isempty(interface) || interface_name_is_valid(interface), -EINVAL);
        assert_return(member_name_is_valid(member), -EINVAL);
        assert_return(reply, -EINVAL);
        assert_return(signature_is_single(type, false), -EINVAL);
        assert_return(BUS_IS_OPEN(bus->state), -ENOTCONN);
        assert_return(!bus_pid_changed(bus), -ECHILD);

        r = sd_bus_call_method(bus, destination, path, "org.freedesktop.DBus.Properties", "Get", error, &rep, "ss", strempty(interface), member);
        if (r < 0)
                return r;

        r = sd_bus_message_enter_container(rep, 'v', type);
        if (r < 0) {
                sd_bus_message_unref(rep);
                return r;
        }

        *reply = rep;
        return 0;
}

static int callback(sd_bus_message *m, void *user, sd_bus_error *error)
{
	sd_event *loop = user;
	int r;
	char *property = NULL;

	r = sd_bus_message_skip(m, "s");
	if (r < 0) {
		fprintf(stderr, "Error skipping message fields: %s\n",
				strerror(-r));
		quit(r, loop);
		return r;
	}

	r = sd_bus_message_enter_container(m, SD_BUS_TYPE_ARRAY, "{sv}");
	if (r < 0) {
		fprintf(stderr, "Error entering container: %s\n",
				strerror(-r));
		quit(r, loop);
		return r;
	}

	while((r = sd_bus_message_enter_container(
					m,
					SD_BUS_TYPE_DICT_ENTRY,
					"sv")) > 0) {
		r = sd_bus_message_read(m, "s", &property);
		if (r < 0) {
			fprintf(stderr, "Error reading message: %s\n",
					strerror(-r));
			quit(r, loop);
			return r;
		}

		if(strcmp(property, "pgood"))
			continue;

		quit(0, loop);
		break;
	}

	return 0;
}

static int print_inhibitors(sd_bus *bus, sd_bus_error *error) {
        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
        const char *what, *who, *why, *mode;
        unsigned int uid, pid;
        unsigned n = 0;
        int r;

        r = sd_bus_call_method(
                        bus,
                        "org.freedesktop.login1",
                        "/org/freedesktop/login1",
                        "org.freedesktop.login1.Manager",
                        "ListInhibitors",
                        error,
                        &reply,
                        "");
        if (r < 0)
                return r;

        r = sd_bus_message_enter_container(reply, SD_BUS_TYPE_ARRAY, "(ssssuu)");
        if (r < 0)
                return bus_log_parse_error(r);

        while ((r = sd_bus_message_read(reply, "(ssssuu)", &what, &who, &why, &mode, &uid, &pid)) > 0) {
                _cleanup_free_ char *comm = NULL, *u = NULL;

                get_process_comm(pid, &comm);
                u = uid_to_name(uid);

                printf("     Who: %s (UID "UID_FMT"/%s, PID "PID_FMT"/%s)\n"
                       "    What: %s\n"
                       "     Why: %s\n"
                       "    Mode: %s\n\n",
                       who, uid, strna(u), pid, strna(comm),
                       what,
                       why,
                       mode);

                n++;
        }
        if (r < 0)
                return bus_log_parse_error(r);

        r = sd_bus_message_exit_container(reply);
        if (r < 0)
                return bus_log_parse_error(r);

        printf("%u inhibitors listed.\n", n);
        return 0;
}

_public_ int sd_bus_get_property_string(
                sd_bus *bus,
                const char *destination,
                const char *path,
                const char *interface,
                const char *member,
                sd_bus_error *error,
                char **ret) {

        _cleanup_(sd_bus_message_unrefp) sd_bus_message *reply = NULL;
        const char *s;
        char *n;
        int r;

        bus_assert_return(bus, -EINVAL, error);
        bus_assert_return(isempty(interface) || interface_name_is_valid(interface), -EINVAL, error);
        bus_assert_return(member_name_is_valid(member), -EINVAL, error);
        bus_assert_return(ret, -EINVAL, error);
        bus_assert_return(!bus_pid_changed(bus), -ECHILD, error);

        if (!BUS_IS_OPEN(bus->state)) {
                r = -ENOTCONN;
                goto fail;
        }

        r = sd_bus_call_method(bus, destination, path, "org.freedesktop.DBus.Properties", "Get", error, &reply, "ss", strempty(interface), member);
        if (r < 0)
                return r;

        r = sd_bus_message_enter_container(reply, 'v', "s");
        if (r < 0)
                goto fail;

        r = sd_bus_message_read_basic(reply, 's', &s);
        if (r < 0)
                goto fail;

        n = strdup(s);
        if (!n) {
                r = -ENOMEM;
                goto fail;
        }

        *ret = n;
        return 0;

fail:
        return sd_bus_error_set_errno(error, r);
}

static void manager_read_name(struct manager *m)
{
	_cleanup_sd_bus_error_ sd_bus_error err = SD_BUS_ERROR_NULL;
	_cleanup_sd_bus_message_ sd_bus_message *rep = NULL;
	const char *name;
	char *str;
	int r;

	r = sd_bus_call_method(m->bus,
			       "org.freedesktop.hostname1",
			       "/org/freedesktop/hostname1",
			       "org.freedesktop.DBus.Properties",
			       "Get",
			       &err,
			       &rep,
			       "ss", "org.freedesktop.hostname1", "Hostname");
	if (r < 0)
		goto error;

	r = sd_bus_message_enter_container(rep, 'v', "s");
	if (r < 0)
		goto error;

	r = sd_bus_message_read(rep, "s", &name);
	if (r < 0)
		name = "undefined";

	if (shl_isempty(name)) {
		log_warning("no hostname set on systemd.hostname1, using: %s",
			    m->friendly_name);
		return;
	}

	str = strdup(name);
	if (!str)
		return log_vENOMEM();

	free(m->friendly_name);
	m->friendly_name = str;
	log_debug("friendly-name from local hostname: %s", str);

	return;

error:
	log_warning("cannot read hostname from systemd.hostname1: %s",
		    bus_error_message(&err, r));
}

static int list_sessions(int argc, char *argv[], void *userdata) {
        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
        const char *id, *user, *seat, *object;
        sd_bus *bus = userdata;
        unsigned k = 0;
        uint32_t uid;
        int r;

        assert(bus);
        assert(argv);

        pager_open_if_enabled();

        r = sd_bus_call_method(
                        bus,
                        "org.freedesktop.login1",
                        "/org/freedesktop/login1",
                        "org.freedesktop.login1.Manager",
                        "ListSessions",
                        &error, &reply,
                        "");
        if (r < 0) {
                log_error("Failed to list sessions: %s", bus_error_message(&error, r));
                return r;
        }

        r = sd_bus_message_enter_container(reply, 'a', "(susso)");
        if (r < 0)
                return bus_log_parse_error(r);

        if (arg_legend)
                printf("%10s %10s %-16s %-16s\n", "SESSION", "UID", "USER", "SEAT");

        while ((r = sd_bus_message_read(reply, "(susso)", &id, &uid, &user, &seat, &object)) > 0) {
                printf("%10s %10u %-16s %-16s\n", id, (unsigned) uid, user, seat);
                k++;
        }
        if (r < 0)
                return bus_log_parse_error(r);

        if (arg_legend)
                printf("\n%u sessions listed.\n", k);

        return 0;
}

static int map_server_address(sd_bus *bus, const char *member, sd_bus_message *m, sd_bus_error *error, void *userdata) {
        char **p = (char **) userdata;
        const void *d;
        int family, r;
        size_t sz;

        assert(p);

        r = sd_bus_message_enter_container(m, 'r', "iay");
        if (r < 0)
                return r;

        r = sd_bus_message_read(m, "i", &family);
        if (r < 0)
                return r;

        r = sd_bus_message_read_array(m, 'y', &d, &sz);
        if (r < 0)
                return r;

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

        if (sz == 0 && family == AF_UNSPEC) {
                *p = mfree(*p);
                return 0;
        }

        if (!IN_SET(family, AF_INET, AF_INET6)) {
                log_error("Unknown address family %i", family);
                return -EINVAL;
        }

        if (sz != FAMILY_ADDRESS_SIZE(family)) {
                log_error("Invalid address size");
                return -EINVAL;
        }

        r = in_addr_to_string(family, d, p);
        if (r < 0)
                return r;

        return 0;
}

static int print_changes(sd_bus_message *m) {
        int r;

        if (arg_quiet)
                return 0;

        r = sd_bus_message_enter_container(m, 'a', "(sss)");
        if (r < 0)
                return bus_log_parse_error(r);

        for (;;) {
                const char *type, *path, *source;

                r = sd_bus_message_read(m, "(sss)", &type, &path, &source);
                if (r < 0)
                        return bus_log_parse_error(r);
                if (r == 0)
                        break;

                if (streq(type, "symlink"))
                        log_info("Created symlink %s %s %s.", path, special_glyph(SPECIAL_GLYPH_ARROW), source);
                else if (streq(type, "copy")) {
                        if (isempty(source))
                                log_info("Copied %s.", path);
                        else
                                log_info("Copied %s %s %s.", source, special_glyph(SPECIAL_GLYPH_ARROW), path);
                } else if (streq(type, "unlink"))
                        log_info("Removed %s.", path);
                else if (streq(type, "write"))
                        log_info("Written %s.", path);
                else if (streq(type, "mkdir"))
                        log_info("Created directory %s.", path);
                else
                        log_error("Unexpected change: %s/%s/%s", type, path, source);
        }

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

        return 0;
}

static int map_ntp_message(sd_bus *bus, const char *member, sd_bus_message *m, sd_bus_error *error, void *userdata) {
        NTPStatusInfo *p = userdata;
        const void *d;
        size_t sz;
        int32_t b;
        int r;

        assert(p);

        r = sd_bus_message_enter_container(m, 'r', "uuuuittayttttbtt");
        if (r < 0)
                return r;

        r = sd_bus_message_read(m, "uuuuitt",
                                &p->leap, &p->version, &p->mode, &p->stratum, &p->precision,
                                &p->root_delay, &p->root_dispersion);
        if (r < 0)
                return r;

        r = sd_bus_message_read_array(m, 'y', &d, &sz);
        if (r < 0)
                return r;

        r = sd_bus_message_read(m, "ttttbtt",
                                &p->origin, &p->recv, &p->trans, &p->dest,
                                &b, &p->packet_count, &p->jitter);
        if (r < 0)
                return r;

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

        if (sz != 4)
                return -EINVAL;

        memcpy(p->reference.str, d, sz);

        p->spike = b;

        return 0;
}

static int list_users(sd_bus *bus, char **args, unsigned n) {
        _cleanup_bus_error_free_ sd_bus_error error = SD_BUS_ERROR_NULL;
        _cleanup_bus_message_unref_ sd_bus_message *reply = NULL;
        const char *user, *object;
        unsigned k = 0;
        uint32_t uid;
        int r;

        pager_open_if_enabled();

        r = sd_bus_call_method(
                        bus,
                        "org.freedesktop.login1",
                        "/org/freedesktop/login1",
                        "org.freedesktop.login1.Manager",
                        "ListUsers",
                        &error, &reply,
                        "");
        if (r < 0) {
                log_error("Failed to list users: %s", bus_error_message(&error, r));
                return r;
        }

        r = sd_bus_message_enter_container(reply, 'a', "(uso)");
        if (r < 0)
                return bus_log_parse_error(r);

        if (arg_legend)
                printf("%10s %-16s\n", "UID", "USER");

        while ((r = sd_bus_message_read(reply, "(uso)", &uid, &user, &object)) > 0) {
                printf("%10u %-16s\n", (unsigned) uid, user);
                k++;
        }
        if (r < 0)
                return bus_log_parse_error(r);

        if (arg_legend)
                printf("\n%u users listed.\n", k);

        return 0;
}