systemd: complement module-console-kit with module-systemd-login

ConsoleKit has been deprecated and replaced by systemd's logind daemon,
hence provide the same functionality of module-console-kit in
module-systemd-login. This also makes sure that the CK module becomes a
NOP if the system is booted with systemd, resp. that the systemd module
becomes a NOP if the system is booted without systemd, thus being nice
to OSes such as Debian which want to support multiple init systems.

configure.ac

@@ -1108,6 +1108,22 @@ AM_CONDITIONAL([HAVE_XEN], [test "x$HAVE_XEN" = x1])
 
 ORC_CHECK([0.4.11])
 
+#### systemd support (optional) ####
+
+AC_ARG_ENABLE([systemd],
+    AS_HELP_STRING([--disable-systemd],[Disable optional systemd support]))
+
+AS_IF([test "x$enable_systemd" != "xno"],
+    [PKG_CHECK_MODULES(SYSTEMD, [ libsystemd-login libsystemd-daemon ], HAVE_SYSTEMD=1, HAVE_SYSTEMD=0)],
+    HAVE_SYSTEMD=0)
+
+AS_IF([test "x$enable_systemd" = "xyes" && test "x$HAVE_SYSTEMD" = "x0"],
+    [AC_MSG_ERROR([*** Needed systemd support not found])])
+
+AC_SUBST(HAVE_SYSTEMD)
+AM_CONDITIONAL([HAVE_SYSTEMD], [test "x$HAVE_SYSTEMD" = x1])
+AS_IF([test "x$HAVE_SYSTEMD" = "x1"], AC_DEFINE([HAVE_SYSTEMD], 1, [Have SYSTEMD?]))
+
 #### Build and Install man pages ####
 
 AC_ARG_ENABLE([manpages],
@@ -1361,6 +1377,7 @@ AS_IF([test "x$HAVE_XEN" = "x1"], ENABLE_XEN=yes, ENABLE_XEN=no)
 AS_IF([test "x$HAVE_DBUS" = "x1"], ENABLE_DBUS=yes, ENABLE_DBUS=no)
 AS_IF([test "x$HAVE_HAL" = "x1"], ENABLE_HAL=yes, ENABLE_HAL=no)
 AS_IF([test "x$HAVE_UDEV" = "x1"], ENABLE_UDEV=yes, ENABLE_UDEV=no)
+AS_IF([test "x$HAVE_SYSTEMD" = "x1"], ENABLE_SYSTEMD=yes, ENABLE_SYSTEMD=no)
 AS_IF([test "x$HAVE_BLUEZ" = "x1"], ENABLE_BLUEZ=yes, ENABLE_BLUEZ=no)
 AS_IF([test "x$HAVE_HAL_COMPAT" = "x1"], ENABLE_HAL_COMPAT=yes, ENABLE_HAL_COMPAT=no)
 AS_IF([test "x$HAVE_TCPWRAP" = "x1"], ENABLE_TCPWRAP=yes, ENABLE_TCPWRAP=no)
@@ -1415,6 +1432,7 @@ echo "
       Enable BlueZ:                ${ENABLE_BLUEZ}
     Enable udev:                   ${ENABLE_UDEV}
       Enable HAL->udev compat:     ${ENABLE_HAL_COMPAT}
+    Enable systemd login:          ${ENABLE_SYSTEMD}
     Enable TCP Wrappers:           ${ENABLE_TCPWRAP}
     Enable libsamplerate:          ${ENABLE_LIBSAMPLERATE}
     Enable IPv6:                   ${ENABLE_IPV6}

src/Makefile.am

@@ -1218,6 +1218,11 @@ modlibexec_LTLIBRARIES += \
 		module-udev-detect.la
 endif
 
+if HAVE_SYSTEMD
+modlibexec_LTLIBRARIES += \
+		module-systemd-login.la
+endif
+
 if HAVE_DBUS
 modlibexec_LTLIBRARIES += \
 		module-rygel-media-server.la \
@@ -1319,6 +1324,7 @@ SYMDEF_FILES = \
 		module-echo-cancel-symdef.h \
 		module-hal-detect-symdef.h \
 		module-udev-detect-symdef.h \
+		module-systemd-login-symdef.h \
 		module-bluetooth-proximity-symdef.h \
 		module-bluetooth-discover-symdef.h \
 		module-bluetooth-device-symdef.h \
@@ -1876,8 +1882,13 @@ module_udev_detect_la_CFLAGS = $(AM_CFLAGS) $(UDEV_CFLAGS)
 
 module_console_kit_la_SOURCES = modules/module-console-kit.c
 module_console_kit_la_LDFLAGS = $(MODULE_LDFLAGS)
-module_console_kit_la_LIBADD = $(MODULE_LIBADD) $(DBUS_LIBS)
-module_console_kit_la_CFLAGS = $(AM_CFLAGS) $(DBUS_CFLAGS)
+module_console_kit_la_LIBADD = $(MODULE_LIBADD) $(DBUS_LIBS) $(SYSTEMD_LIBS)
+module_console_kit_la_CFLAGS = $(AM_CFLAGS) $(DBUS_CFLAGS) $(SYSTEMD_CFLAGS)
+
+module_systemd_login_la_SOURCES = modules/module-systemd-login.c
+module_systemd_login_la_LDFLAGS = $(MODULE_LDFLAGS)
+module_systemd_login_la_LIBADD = $(MODULE_LIBADD) $(SYSTEMD_LIBS)
+module_systemd_login_la_CFLAGS = $(AM_CFLAGS) $(SYSTEMD_CFLAGS)
 
 # GConf support
 module_gconf_la_SOURCES = modules/gconf/module-gconf.c

src/daemon/default.pa.in

@@ -150,6 +150,9 @@ load-module module-suspend-on-idle
 .ifexists module-console-kit@PA_SOEXT@
 load-module module-console-kit
 .endif
+.ifexists module-systemd-login@PA_SOEXT@
+load-module module-systemd-login
+.endif
 
 ### Enable positioned event sounds
 load-module module-position-event-sounds

src/modules/module-console-kit.c

@@ -30,6 +30,11 @@
 #include <stdlib.h>
 #include <sys/types.h>
 
+#ifdef HAVE_SYSTEMD
+#include <systemd/sd-login.h>
+#include <systemd/sd-daemon.h>
+#endif
+
 #include <pulse/xmalloc.h>
 
 #include <pulsecore/module.h>
@@ -280,6 +285,13 @@ int pa__init(pa_module*m) {
 
     dbus_error_init(&error);
 
+#ifdef HAVE_SYSTEMD
+    /* If systemd support is enabled and we boot on systemd we
+       shouldn't watch ConsoleKit but systemd's logind service. */
+    if (sd_booted() > 0)
+        return 0;
+#endif
+
     if (!(ma = pa_modargs_new(m->argument, valid_modargs))) {
         pa_log("Failed to parse module arguments");
         goto fail;

src/modules/module-systemd-login.c

@@ -0,0 +1,243 @@
+/***
+    This file is part of PulseAudio.
+
+    Copyright 2012 Lennart Poettering
+
+    PulseAudio 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.
+
+    PulseAudio 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
+    General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public License
+    along with PulseAudio; if not, write to the Free Software
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
+    USA.
+***/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <sys/types.h>
+
+#include <systemd/sd-login.h>
+#include <systemd/sd-daemon.h>
+
+#include <pulse/xmalloc.h>
+
+#include <pulsecore/module.h>
+#include <pulsecore/log.h>
+#include <pulsecore/hashmap.h>
+#include <pulsecore/idxset.h>
+#include <pulsecore/modargs.h>
+
+#include "module-systemd-login-symdef.h"
+
+PA_MODULE_AUTHOR("Lennart Poettering");
+PA_MODULE_DESCRIPTION("Create a client for each login session of this user");
+PA_MODULE_VERSION(PACKAGE_VERSION);
+PA_MODULE_LOAD_ONCE(TRUE);
+
+static const char* const valid_modargs[] = {
+    NULL
+};
+
+struct session {
+    char *id;
+    pa_client *client;
+};
+
+struct userdata {
+    pa_module *module;
+    pa_core *core;
+    pa_hashmap *sessions, *previous_sessions;
+    sd_login_monitor *monitor;
+    pa_io_event *io;
+};
+
+static int add_session(struct userdata *u, const char *id) {
+    struct session *session;
+    pa_client_new_data data;
+
+    session = pa_xnew(struct session, 1);
+    session->id = pa_xstrdup(id);
+
+    pa_client_new_data_init(&data);
+    data.module = u->module;
+    data.driver = __FILE__;
+    pa_proplist_setf(data.proplist, PA_PROP_APPLICATION_NAME, "Login Session %s", id);
+    pa_proplist_sets(data.proplist, "systemd-login.session", id);
+    session->client = pa_client_new(u->core, &data);
+    pa_client_new_data_done(&data);
+
+    if (!session->client) {
+        pa_xfree(session->id);
+        pa_xfree(session);
+        return -1;
+    }
+
+    pa_hashmap_put(u->sessions, session->id, session);
+
+    pa_log_debug("Added new session %s", id);
+    return 0;
+}
+
+static void free_session(struct session *session) {
+    pa_assert(session);
+
+    pa_log_debug("Removing session %s", session->id);
+
+    pa_client_free(session->client);
+    pa_xfree(session->id);
+    pa_xfree(session);
+}
+
+static int get_session_list(struct userdata *u) {
+    int r;
+    char **sessions;
+    pa_hashmap *h;
+    struct session *o;
+
+    pa_assert(u);
+
+    r = sd_uid_get_sessions(getuid(), 0, &sessions);
+    if (r < 0)
+        return -1;
+
+    /* We copy all sessions that still exist from one hashmap to the
+     * other and then flush the remaining ones */
+
+    h = u->previous_sessions;
+    u->previous_sessions = u->sessions;
+    u->sessions = h;
+
+    if (sessions) {
+        char **s;
+
+        /* Note that the sessions array is allocated with libc's
+         * malloc()/free() calls, hence do not use pa_xfree() to free
+         * this here. */
+
+        for (s = sessions; *s; s++) {
+            o = pa_hashmap_remove(u->previous_sessions, *s);
+            if (o)
+                pa_hashmap_put(u->sessions, o->id, o);
+            else
+                add_session(u, *s);
+
+            free(*s);
+        }
+
+        free(sessions);
+    }
+
+    while ((o = pa_hashmap_steal_first(u->previous_sessions)))
+        free_session(o);
+
+    return 0;
+}
+
+static void monitor_cb(
+        pa_mainloop_api*a,
+        pa_io_event* e,
+        int fd,
+        pa_io_event_flags_t events,
+        void *userdata) {
+
+    struct userdata *u = userdata;
+
+    pa_assert(u);
+
+    sd_login_monitor_flush(u->monitor);
+    get_session_list(u);
+}
+
+int pa__init(pa_module *m) {
+    struct userdata *u = NULL;
+    pa_modargs *ma;
+    sd_login_monitor *monitor = NULL;
+    int r;
+
+    pa_assert(m);
+
+    /* If we are not actually booting with systemd become a NOP */
+    if (sd_booted() <= 0)
+        return 0;
+
+    ma = pa_modargs_new(m->argument, valid_modargs);
+    if (!ma) {
+        pa_log("Failed to parse module arguments");
+        goto fail;
+    }
+
+    r = sd_login_monitor_new("session", &monitor);
+    if (r < 0) {
+        pa_log("Failed to create session monitor: %s", strerror(-r));
+        goto fail;
+    }
+
+    m->userdata = u = pa_xnew0(struct userdata, 1);
+    u->core = m->core;
+    u->module = m;
+    u->sessions = pa_hashmap_new(pa_idxset_string_hash_func, pa_idxset_string_compare_func);
+    u->previous_sessions = pa_hashmap_new(pa_idxset_string_hash_func, pa_idxset_string_compare_func);
+    u->monitor = monitor;
+
+    u->io = u->core->mainloop->io_new(u->core->mainloop, sd_login_monitor_get_fd(monitor), PA_IO_EVENT_INPUT, monitor_cb, u);
+
+    if (get_session_list(u) < 0)
+        goto fail;
+
+    pa_modargs_free(ma);
+
+    return 0;
+
+fail:
+    if (ma)
+        pa_modargs_free(ma);
+
+    pa__done(m);
+
+    return -1;
+}
+
+void pa__done(pa_module *m) {
+    struct userdata *u;
+    struct session *session;
+
+    pa_assert(m);
+
+    u = m->userdata;
+    if (!u)
+        return;
+
+    if (u->sessions) {
+        while ((session = pa_hashmap_steal_first(u->sessions)))
+            free_session(session);
+
+        pa_hashmap_free(u->sessions, NULL, NULL);
+
+        while ((session = pa_hashmap_steal_first(u->previous_sessions)))
+            free_session(session);
+
+        pa_hashmap_free(u->previous_sessions, NULL, NULL);
+    }
+
+    if (u->io)
+        m->core->mainloop->io_free(u->io);
+
+    if (u->monitor)
+        sd_login_monitor_unref(u->monitor);
+
+    pa_xfree(u);
+}