hostname: add new hostnamectl tool as text client for hostnamed

9 files changed, 809 insertions, 8 deletions

diff --git a/.gitignore b/.gitignore
index bc72be8210..c41db45be2 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
+/hostnamectl
 /timedatectl
 /test-date
 /install-tree
diff --git a/Makefile.am b/Makefile.am
index ad7a749cac..8e88c42c8f 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -3062,6 +3062,25 @@ MANPAGES_ALIAS += \
 	man/systemd-hostnamed.8
 
 man/systemd-hostnamed.8: man/systemd-hostnamed.service.8
+
+hostnamectl_SOURCES = \
+	src/hostname/hostnamectl.c
+
+hostnamectl_CFLAGS = \
+	$(AM_CFLAGS) \
+	$(DBUS_CFLAGS)
+
+hostnamectl_LDADD = \
+	libsystemd-shared.la \
+	libsystemd-dbus.la \
+	libsystemd-id128-internal.la
+
+bin_PROGRAMS += \
+	hostnamectl
+
+MANPAGES += \
+	man/hostnamectl.1
+
 endif
 
 polkitpolicy_in_files += \
diff --git a/man/hostname.xml b/man/hostname.xml
index 2ada32ff71..84a2961664 100644
--- a/man/hostname.xml
+++ b/man/hostname.xml
@@ -70,6 +70,11 @@
                 <para>Depending on the operating system other
                 configuration files might be checked for configuration
                 of the host name as well, however only as fallback.</para>
+
+                <para>You may use
+                <citerefentry><refentrytitle>hostnamectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+                to change the value of this file from the command
+                line.</para>
         </refsect1>
 
         <refsect1>
@@ -88,7 +93,9 @@
                           <citerefentry><refentrytitle>hostname</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
                           <citerefentry><refentrytitle>hostname</refentrytitle><manvolnum>7</manvolnum></citerefentry>,
                           <citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
-                          <citerefentry><refentrytitle>machine-info</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+                          <citerefentry><refentrytitle>machine-info</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+                          <citerefentry><refentrytitle>hostnamectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+                          <citerefentry><refentrytitle>systemd-hostnamed.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
                   </para>
         </refsect1>
 
diff --git a/man/hostnamectl.xml b/man/hostnamectl.xml
new file mode 100644
index 0000000000..955e79bfd7
--- /dev/null
+++ b/man/hostnamectl.xml
@@ -0,0 +1,228 @@
+<?xml version='1.0'?> <!--*-nxml-*-->
+<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN"
+        "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd">
+
+<!--
+  This file is part of systemd.
+
+  Copyright 2012 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+-->
+
+<refentry id="hostnamectl">
+
+        <refentryinfo>
+                <title>hostnamectl</title>
+                <productname>systemd</productname>
+
+                <authorgroup>
+                        <author>
+                                <contrib>Developer</contrib>
+                                <firstname>Lennart</firstname>
+                                <surname>Poettering</surname>
+                                <email>lennart@poettering.net</email>
+                        </author>
+                </authorgroup>
+        </refentryinfo>
+
+        <refmeta>
+                <refentrytitle>hostnamectl</refentrytitle>
+                <manvolnum>1</manvolnum>
+        </refmeta>
+
+        <refnamediv>
+                <refname>hostnamectl</refname>
+                <refpurpose>Control the system hostname</refpurpose>
+        </refnamediv>
+
+        <refsynopsisdiv>
+                <cmdsynopsis>
+                        <command>hostnamectl <arg choice="opt" rep="repeat">OPTIONS</arg> <arg choice="req">COMMAND</arg></command>
+                </cmdsynopsis>
+        </refsynopsisdiv>
+
+        <refsect1>
+                <title>Description</title>
+
+                <para><command>hostnamectl</command> may be used to
+                query and change the system hostname and related
+               settings.</para>
+
+                <para>This tool distuingishes three different host
+                names: the high-level "pretty" hostname which might
+                include all all kinds of special characters
+                (e.g. "Lennart's Laptop"), the static hostname which
+                is used to initialize the kernel hostname at boot
+                (e.g. "lennarts-laptop"), and the transient hostname
+                which might be assigned temporarily due to network
+                configuration and might revert back to the static
+                hostname if network connectivity is lost and is only
+                temporarily written to the kernel hostname
+                (e.g. "dhcp-47-11").</para>
+
+                <para>Note that the pretty hostname has little
+                restrictions on the characters used, while the static
+                and transient hostnames are limited to the usually
+                accepted characters of internet domain names.</para>
+
+                <para>The static host name is stored in
+                <filename>/etc/hostname</filename>, see
+                <citerefentry><refentrytitle>hostname</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+                for more information. The pretty host name and icon
+                name are stored in
+                <filename>/etc/machine-info</filename>, see
+                <citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry>.</para>
+        </refsect1>
+
+        <refsect1>
+                <title>Options</title>
+
+                <para>The following options are understood:</para>
+
+                <variablelist>
+                        <varlistentry>
+                                <term><option>--help</option></term>
+                                <term><option>-h</option></term>
+
+                                <listitem><para>Prints a short help
+                                text and exits.</para></listitem>
+                        </varlistentry>
+
+                        <varlistentry>
+                                <term><option>--version</option></term>
+
+                                <listitem><para>Prints a short version
+                                string and exits.</para></listitem>
+                        </varlistentry>
+
+                        <varlistentry>
+                                <term><option>--no-ask-password</option></term>
+
+                                <listitem><para>Don't query the user
+                                for authentication for privileged
+                                operations.</para></listitem>
+                        </varlistentry>
+
+                        <varlistentry>
+                                <term><option>-H</option></term>
+                                <term><option>--host</option></term>
+
+                                <listitem><para>Execute operation
+                                remotely. Specify a hostname, or
+                                username and hostname separated by @,
+                                to connect to. This will use SSH to
+                                talk to a remote
+                                system.</para></listitem>
+                        </varlistentry>
+
+                        <varlistentry>
+                                <term><option>--static</option></term>
+                                <term><option>--transient</option></term>
+                                <term><option>--pretty</option></term>
+
+                                <listitem><para>If
+                                <command>set-hostname</command> is
+                                invoked and one or more of these
+                                options are passed only the selected
+                                hostnames is
+                                updated.</para></listitem>
+                        </varlistentry>
+                </variablelist>
+
+                <para>The following commands are understood:</para>
+
+                <variablelist>
+                        <varlistentry>
+                                <term><command>status</command></term>
+
+                                <listitem><para>Show current system
+                                hostname and related
+                                information.</para></listitem>
+                        </varlistentry>
+
+                        <varlistentry>
+                                <term><command>set-hostname [NAME]</command></term>
+
+                                <listitem><para>Set the system
+                                hostname. By default this will alter
+                                the pretty, the static, and the
+                                transient hostname alike, however if
+                                one or more of
+                                <option>--static</option>,
+                                <option>--transient</option>,
+                                <option>--pretty</option> are used
+                                only the selected hostnames are
+                                changed. If the pretty hostname is
+                                being set, and static or transient are
+                                being set as well the specified host
+                                name will be simplified in regards to
+                                the character set used before the
+                                latter are updated. This is done by
+                                replacing spaces by "-" and removing
+                                special characters. This ensures that
+                                the pretty and the static hostname
+                                are always closely related while still
+                                following the validity rules of the
+                                specific name. This simplification of
+                                the hostname string is not done if
+                                only the transient and/or static host
+                                names are set, and the pretty host
+                                name is left untouched. Pass the empty
+                                string "" as hostname to reset the
+                                selected hostnames to their default
+                                (usually
+                                "localhost").</para></listitem>
+                        </varlistentry>
+
+                        <varlistentry>
+                                <term><command>set-icon-name [NAME]</command></term>
+
+                                <listitem><para>Set the system icon
+                                name. The icon name is used by some
+                                graphical applications to visualize
+                                this host. The icon name should follow
+                                the <ulink
+                                url="http://standards.freedesktop.org/icon-naming-spec/icon-naming-spec-latest.html">Icon
+                                Naming Specification</ulink>. Pass an
+                                empty string to this operatoin to
+                                reset the icon name to the default
+                                value which is determined from the
+                                system form factor and possibly other
+                                parameters.</para></listitem>
+                        </varlistentry>
+
+                </variablelist>
+        </refsect1>
+
+        <refsect1>
+                <title>Exit status</title>
+
+                <para>On success 0 is returned, a non-zero failure
+                code otherwise.</para>
+        </refsect1>
+
+        <refsect1>
+                <title>See Also</title>
+                <para>
+                        <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+                        <citerefentry><refentrytitle>hostname</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+                        <citerefentry><refentrytitle>hostname</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+                        <citerefentry><refentrytitle>machine-info</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+                        <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+                        <citerefentry><refentrytitle>systemd-hostnamed.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
+                </para>
+        </refsect1>
+
+</refentry>
diff --git a/man/localtime.xml b/man/localtime.xml
index c0e87bf78f..88c84a3682 100644
--- a/man/localtime.xml
+++ b/man/localtime.xml
@@ -82,14 +82,21 @@
                 <para>The time zone may be overridden for individual
                 programs by using the TZ environment variable. See
                 <citerefentry><refentrytitle>environ</refentrytitle><manvolnum>7</manvolnum></citerefentry>.</para>
+
+                <para>You may use
+                <citerefentry><refentrytitle>timedatectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+                to change the settings of this file from the command
+                line.</para>
         </refsect1>
 
         <refsect1>
                   <title>See Also</title>
                   <para>
-                          <citerefentry><refentrytitle>tzset</refentrytitle><manvolnum>3</manvolnum></citerefentry>
-                          <citerefentry><refentrytitle>localtime</refentrytitle><manvolnum>3</manvolnum></citerefentry>
-                          <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+                          <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+                          <citerefentry><refentrytitle>tzset</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+                          <citerefentry><refentrytitle>localtime</refentrytitle><manvolnum>3</manvolnum></citerefentry>,
+                          <citerefentry><refentrytitle>timedatectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+                          <citerefentry><refentrytitle>systemd-timedated.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
                   </para>
         </refsect1>
 
diff --git a/man/machine-info.xml b/man/machine-info.xml
index e27b600211..b310d71334 100644
--- a/man/machine-info.xml
+++ b/man/machine-info.xml
@@ -74,6 +74,11 @@
                 <para>Depending on the operating system other
                 configuration files might be checked for machine
                 information as well, however only as fallback.</para>
+
+                <para>You may use
+                <citerefentry><refentrytitle>hostnamectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>
+                to change the settings of this file from the command
+                line.</para>
         </refsect1>
 
         <refsect1>
@@ -140,7 +145,9 @@ ICON_NAME=computer-laptop</programlisting>
                           <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
                           <citerefentry><refentrytitle>os-release</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
                           <citerefentry><refentrytitle>hostname</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
-                          <citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+                          <citerefentry><refentrytitle>machine-id</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+                          <citerefentry><refentrytitle>hostnamectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+                          <citerefentry><refentrytitle>systemd-hostnamed.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
                   </para>
         </refsect1>
 
diff --git a/man/systemd-hostnamed.service.xml b/man/systemd-hostnamed.service.xml
index 9fee2a096d..555bb7a2df 100644
--- a/man/systemd-hostnamed.service.xml
+++ b/man/systemd-hostnamed.service.xml
@@ -74,8 +74,9 @@
                 <para>
                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
                         <citerefentry><refentrytitle>hostname</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
-                        <citerefentry><refentrytitle>sethostname</refentrytitle><manvolnum>2</manvolnum></citerefentry>,
-                        <citerefentry><refentrytitle>machine-info</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+                        <citerefentry><refentrytitle>machine-info</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
+                        <citerefentry><refentrytitle>hostnamectl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+                        <citerefentry><refentrytitle>sethostname</refentrytitle><manvolnum>2</manvolnum></citerefentry>
                 </para>
         </refsect1>
 
diff --git a/man/timedatectl.xml b/man/timedatectl.xml
index 8fb4e38f37..9065577692 100644
--- a/man/timedatectl.xml
+++ b/man/timedatectl.xml
@@ -154,7 +154,12 @@
                                 <command>list-timezones</command>. If
                                 the RTC is configured to be in the
                                 local time this will also update the
-                                RTC time.</para></listitem>
+                                RTC time. This call will alter the
+                                <filename>/etc/localtime</filename>
+                                symlink. See
+                                <citerefentry><refentrytitle>localtime</refentrytitle><manvolnum>5</manvolnum></citerefentry>
+                                for more
+                                information.</para></listitem>
                         </varlistentry>
 
                         <varlistentry>
@@ -235,6 +240,7 @@
                         <citerefentry><refentrytitle>systemd</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
                         <citerefentry><refentrytitle>hwclock</refentrytitle><manvolnum>8</manvolnum></citerefentry>,
                         <citerefentry><refentrytitle>date</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
+                        <citerefentry><refentrytitle>localtime</refentrytitle><manvolnum>5</manvolnum></citerefentry>,
                         <citerefentry><refentrytitle>systemctl</refentrytitle><manvolnum>1</manvolnum></citerefentry>,
                         <citerefentry><refentrytitle>systemd-timedated.service</refentrytitle><manvolnum>8</manvolnum></citerefentry>
                 </para>
diff --git a/src/hostname/hostnamectl.c b/src/hostname/hostnamectl.c
new file mode 100644
index 0000000000..de2f7242ea
--- /dev/null
+++ b/src/hostname/hostnamectl.c
@@ -0,0 +1,525 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2012 Lennart Poettering
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include <stdlib.h>
+#include <stdbool.h>
+#include <unistd.h>
+#include <getopt.h>
+#include <string.h>
+#include <sys/timex.h>
+
+#include "dbus-common.h"
+#include "util.h"
+#include "spawn-polkit-agent.h"
+#include "build.h"
+#include "hwclock.h"
+#include "strv.h"
+#include "sd-id128.h"
+#include "virt.h"
+
+static enum transport {
+        TRANSPORT_NORMAL,
+        TRANSPORT_SSH,
+        TRANSPORT_POLKIT
+} arg_transport = TRANSPORT_NORMAL;
+static bool arg_ask_password = true;
+static const char *arg_host = NULL;
+static bool arg_set_transient = false;
+static bool arg_set_pretty = false;
+static bool arg_set_static = false;
+
+static void polkit_agent_open_if_enabled(void) {
+
+        /* Open the polkit agent as a child process if necessary */
+
+        if (!arg_ask_password)
+                return;
+
+        polkit_agent_open();
+}
+
+typedef struct StatusInfo {
+        const char *hostname;
+        const char *static_hostname;
+        const char *pretty_hostname;
+        const char *icon_name;
+} StatusInfo;
+
+static void print_status_info(StatusInfo *i) {
+        sd_id128_t mid, bid;
+        int r;
+        const char *id;
+
+        assert(i);
+
+        printf("   Static hostname: %s\n",
+               strna(i->static_hostname));
+
+        if (!streq_ptr(i->hostname, i->static_hostname))
+                printf("Transient hostname: %s\n",
+                       strna(i->hostname));
+
+        printf("   Pretty hostname: %s\n"
+               "         Icon name: %s\n",
+               strna(i->pretty_hostname),
+               strna(i->icon_name));
+
+        r = sd_id128_get_machine(&mid);
+        if (r >= 0)
+                printf("        Machine ID: " SD_ID128_FORMAT_STR "\n", SD_ID128_FORMAT_VAL(mid));
+
+        r = sd_id128_get_boot(&bid);
+        if (r >= 0)
+                printf("           Boot ID: " SD_ID128_FORMAT_STR "\n", SD_ID128_FORMAT_VAL(bid));
+
+        if (detect_virtualization(&id) >= 0)
+                printf("    Virtualization: %s\n", id);
+}
+
+static int status_property(const char *name, DBusMessageIter *iter, StatusInfo *i) {
+        assert(name);
+        assert(iter);
+
+        switch (dbus_message_iter_get_arg_type(iter)) {
+
+        case DBUS_TYPE_STRING: {
+                const char *s;
+
+                dbus_message_iter_get_basic(iter, &s);
+                if (!isempty(s)) {
+                        if (streq(name, "Hostname"))
+                                i->hostname = s;
+                        if (streq(name, "StaticHostname"))
+                                i->static_hostname = s;
+                        if (streq(name, "PrettyHostname"))
+                                i->pretty_hostname = s;
+                        if (streq(name, "IconName"))
+                                i->icon_name = s;
+                }
+                break;
+        }
+        }
+
+        return 0;
+}
+
+static int show_status(DBusConnection *bus, char **args, unsigned n) {
+        _cleanup_dbus_message_unref_ DBusMessage *reply = NULL;
+        const char *interface = "";
+        int r;
+        DBusMessageIter iter, sub, sub2, sub3;
+        StatusInfo info;
+
+        assert(args);
+
+        r = bus_method_call_with_reply(
+                        bus,
+                        "org.freedesktop.hostname1",
+                        "/org/freedesktop/hostname1",
+                        "org.freedesktop.DBus.Properties",
+                        "GetAll",
+                        &reply,
+                        NULL,
+                        DBUS_TYPE_STRING, &interface,
+                        DBUS_TYPE_INVALID);
+        if (r < 0)
+                return r;
+
+        if (!dbus_message_iter_init(reply, &iter) ||
+            dbus_message_iter_get_arg_type(&iter) != DBUS_TYPE_ARRAY ||
+            dbus_message_iter_get_element_type(&iter) != DBUS_TYPE_DICT_ENTRY)  {
+                log_error("Failed to parse reply.");
+                return -EIO;
+        }
+
+        zero(info);
+        dbus_message_iter_recurse(&iter, &sub);
+
+        while (dbus_message_iter_get_arg_type(&sub) != DBUS_TYPE_INVALID) {
+                const char *name;
+
+                if (dbus_message_iter_get_arg_type(&sub) != DBUS_TYPE_DICT_ENTRY) {
+                        log_error("Failed to parse reply.");
+                        return -EIO;
+                }
+
+                dbus_message_iter_recurse(&sub, &sub2);
+
+                if (bus_iter_get_basic_and_next(&sub2, DBUS_TYPE_STRING, &name, true) < 0) {
+                        log_error("Failed to parse reply.");
+                        return -EIO;
+                }
+
+                if (dbus_message_iter_get_arg_type(&sub2) != DBUS_TYPE_VARIANT)  {
+                        log_error("Failed to parse reply.");
+                        return -EIO;
+                }
+
+                dbus_message_iter_recurse(&sub2, &sub3);
+
+                r = status_property(name, &sub3, &info);
+                if (r < 0) {
+                        log_error("Failed to parse reply.");
+                        return r;
+                }
+
+                dbus_message_iter_next(&sub);
+        }
+
+        print_status_info(&info);
+        return 0;
+}
+
+static char* hostname_simplify(char *s) {
+        char *p, *d;
+
+        for (p = s, d = s; *p; p++) {
+                if ((*p >= 'a' && *p <= 'z') ||
+                    (*p >= '0' && *p <= '9') ||
+                    *p == '-' || *p == '_')
+                        *(d++) = *p;
+                else if (*p >= 'A' && *p <= 'Z')
+                        *(d++) = *p - 'A' + 'a';
+                else if (*p == ' ')
+                        *(d++) = '-';
+        }
+
+        *d = 0;
+
+        strshorten(s, HOST_NAME_MAX);
+        return s;
+}
+
+static int set_hostname(DBusConnection *bus, char **args, unsigned n) {
+        _cleanup_dbus_message_unref_ DBusMessage *reply = NULL;
+        dbus_bool_t interactive = true;
+        _cleanup_free_ char *h = NULL;
+        const char *hostname = args[1];
+        int r;
+
+        assert(args);
+        assert(n == 2);
+
+        polkit_agent_open_if_enabled();
+
+        if (arg_set_pretty) {
+                r = bus_method_call_with_reply(
+                                bus,
+                                "org.freedesktop.hostname1",
+                                "/org/freedesktop/hostname1",
+                                "org.freedesktop.hostname1",
+                                "SetPrettyHostname",
+                                &reply,
+                                NULL,
+                                DBUS_TYPE_STRING, &hostname,
+                                DBUS_TYPE_BOOLEAN, &interactive,
+                                DBUS_TYPE_INVALID);
+                if (r < 0)
+                        return r;
+
+                h = strdup(hostname);
+                if (!h)
+                        return log_oom();
+
+                hostname = hostname_simplify(h);
+        }
+
+        if (arg_set_static) {
+                r = bus_method_call_with_reply(
+                                bus,
+                                "org.freedesktop.hostname1",
+                                "/org/freedesktop/hostname1",
+                                "org.freedesktop.hostname1",
+                                "SetStaticHostname",
+                                &reply,
+                                NULL,
+                                DBUS_TYPE_STRING, &hostname,
+                                DBUS_TYPE_BOOLEAN, &interactive,
+                                DBUS_TYPE_INVALID);
+
+                if (r < 0)
+                        return r;
+        }
+
+        if (arg_set_transient) {
+                r = bus_method_call_with_reply(
+                                bus,
+                                "org.freedesktop.hostname1",
+                                "/org/freedesktop/hostname1",
+                                "org.freedesktop.hostname1",
+                                "SetHostname",
+                                &reply,
+                                NULL,
+                                DBUS_TYPE_STRING, &hostname,
+                                DBUS_TYPE_BOOLEAN, &interactive,
+                                DBUS_TYPE_INVALID);
+
+                if (r < 0)
+                        return r;
+        }
+
+        return 0;
+}
+
+static int set_icon_name(DBusConnection *bus, char **args, unsigned n) {
+        _cleanup_dbus_message_unref_ DBusMessage *reply = NULL;
+        dbus_bool_t interactive = true;
+
+        assert(args);
+        assert(n == 2);
+
+        polkit_agent_open_if_enabled();
+
+        return bus_method_call_with_reply(
+                        bus,
+                        "org.freedesktop.hostname1",
+                        "/org/freedesktop/hostname1",
+                        "org.freedesktop.hostname1",
+                        "SetIconName",
+                        &reply,
+                        NULL,
+                        DBUS_TYPE_STRING, &args[1],
+                        DBUS_TYPE_BOOLEAN, &interactive,
+                        DBUS_TYPE_INVALID);
+}
+
+static int help(void) {
+
+        printf("%s [OPTIONS...] {COMMAND} ...\n\n"
+               "Query or set system hostname.\n\n"
+               "  -h --help              Show this help\n"
+               "     --version           Show package version\n"
+               "     --no-ask-password   Do not prompt for password\n"
+               "     --transient         Only set transient hostname\n"
+               "     --static            Only set static hostname\n"
+               "     --pretty            Only set pretty hostname\n"
+               "  -H --host=[USER@]HOST  Operate on remote host\n\n"
+               "Commands:\n"
+               "  status                          Show current hostname settings\n"
+               "  set-hostname [NAME]             Set system hostname\n"
+               "  set-icon-name [NAME]            Set icon name for host\n",
+               program_invocation_short_name);
+
+        return 0;
+}
+
+static int parse_argv(int argc, char *argv[]) {
+
+        enum {
+                ARG_VERSION = 0x100,
+                ARG_NO_ASK_PASSWORD,
+                ARG_SET_TRANSIENT,
+                ARG_SET_STATIC,
+                ARG_SET_PRETTY
+        };
+
+        static const struct option options[] = {
+                { "help",            no_argument,       NULL, 'h'                 },
+                { "version",         no_argument,       NULL, ARG_VERSION         },
+                { "transient",       no_argument,       NULL, ARG_SET_TRANSIENT   },
+                { "static",          no_argument,       NULL, ARG_SET_STATIC      },
+                { "pretty",          no_argument,       NULL, ARG_SET_PRETTY      },
+                { "host",            required_argument, NULL, 'H'                 },
+                { "privileged",      no_argument,       NULL, 'P'                 },
+                { "no-ask-password", no_argument,       NULL, ARG_NO_ASK_PASSWORD },
+                { NULL,              0,                 NULL, 0                   }
+        };
+
+        int c;
+
+        assert(argc >= 0);
+        assert(argv);
+
+        while ((c = getopt_long(argc, argv, "hp:as:H:P", options, NULL)) >= 0) {
+
+                switch (c) {
+
+                case 'h':
+                        help();
+                        return 0;
+
+                case ARG_VERSION:
+                        puts(PACKAGE_STRING);
+                        puts(DISTRIBUTION);
+                        puts(SYSTEMD_FEATURES);
+                        return 0;
+
+                case 'P':
+                        arg_transport = TRANSPORT_POLKIT;
+                        break;
+
+                case 'H':
+                        arg_transport = TRANSPORT_SSH;
+                        arg_host = optarg;
+                        break;
+
+                case ARG_SET_TRANSIENT:
+                        arg_set_transient = true;
+                        break;
+
+                case ARG_SET_PRETTY:
+                        arg_set_pretty = true;
+                        break;
+
+                case ARG_SET_STATIC:
+                        arg_set_static = true;
+                        break;
+
+                case '?':
+                        return -EINVAL;
+
+                default:
+                        log_error("Unknown option code %c", c);
+                        return -EINVAL;
+                }
+        }
+
+        if (!arg_set_transient && !arg_set_pretty && !arg_set_static)
+                arg_set_transient = arg_set_pretty = arg_set_static = true;
+
+        return 1;
+}
+
+static int hostnamectl_main(DBusConnection *bus, int argc, char *argv[], DBusError *error) {
+
+        static const struct {
+                const char* verb;
+                const enum {
+                        MORE,
+                        LESS,
+                        EQUAL
+                } argc_cmp;
+                const int argc;
+                int (* const dispatch)(DBusConnection *bus, char **args, unsigned n);
+        } verbs[] = {
+                { "status",              LESS,   1, show_status         },
+                { "set-hostname",        LESS,   2, set_hostname        },
+                { "set-icon-name",       EQUAL,  2, set_icon_name       },
+        };
+
+        int left;
+        unsigned i;
+
+        assert(argc >= 0);
+        assert(argv);
+        assert(error);
+
+        left = argc - optind;
+
+        if (left <= 0)
+                /* Special rule: no arguments means "status" */
+                i = 0;
+        else {
+                if (streq(argv[optind], "help")) {
+                        help();
+                        return 0;
+                }
+
+                for (i = 0; i < ELEMENTSOF(verbs); i++)
+                        if (streq(argv[optind], verbs[i].verb))
+                                break;
+
+                if (i >= ELEMENTSOF(verbs)) {
+                        log_error("Unknown operation %s", argv[optind]);
+                        return -EINVAL;
+                }
+        }
+
+        switch (verbs[i].argc_cmp) {
+
+        case EQUAL:
+                if (left != verbs[i].argc) {
+                        log_error("Invalid number of arguments.");
+                        return -EINVAL;
+                }
+
+                break;
+
+        case MORE:
+                if (left < verbs[i].argc) {
+                        log_error("Too few arguments.");
+                        return -EINVAL;
+                }
+
+                break;
+
+        case LESS:
+                if (left > verbs[i].argc) {
+                        log_error("Too many arguments.");
+                        return -EINVAL;
+                }
+
+                break;
+
+        default:
+                assert_not_reached("Unknown comparison operator.");
+        }
+
+        if (!bus) {
+                log_error("Failed to get D-Bus connection: %s", error->message);
+                return -EIO;
+        }
+
+        return verbs[i].dispatch(bus, argv + optind, left);
+}
+
+int main(int argc, char *argv[]) {
+        int r, retval = EXIT_FAILURE;
+        DBusConnection *bus = NULL;
+        DBusError error;
+
+        dbus_error_init(&error);
+
+        log_parse_environment();
+        log_open();
+
+        r = parse_argv(argc, argv);
+        if (r < 0)
+                goto finish;
+        else if (r == 0) {
+                retval = EXIT_SUCCESS;
+                goto finish;
+        }
+
+        if (arg_transport == TRANSPORT_NORMAL)
+                bus = dbus_bus_get_private(DBUS_BUS_SYSTEM, &error);
+        else if (arg_transport == TRANSPORT_POLKIT)
+                bus_connect_system_polkit(&bus, &error);
+        else if (arg_transport == TRANSPORT_SSH)
+                bus_connect_system_ssh(NULL, arg_host, &bus, &error);
+        else
+                assert_not_reached("Uh, invalid transport...");
+
+        r = hostnamectl_main(bus, argc, argv, &error);
+        retval = r < 0 ? EXIT_FAILURE : r;
+
+finish:
+        if (bus) {
+                dbus_connection_flush(bus);
+                dbus_connection_close(bus);
+                dbus_connection_unref(bus);
+        }
+
+        dbus_error_free(&error);
+        dbus_shutdown();
+
+        return retval;
+}