1/***
2    This file is part of PulseAudio.
3
4    Copyright 2012 Lennart Poettering
5
6    PulseAudio is free software; you can redistribute it and/or modify
7    it under the terms of the GNU Lesser General Public License as published
8    by the Free Software Foundation; either version 2.1 of the License,
9    or (at your option) any later version.
10
11    PulseAudio is distributed in the hope that it will be useful, but
12    WITHOUT ANY WARRANTY; without even the implied warranty of
13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14    General Public License for more details.
15
16    You should have received a copy of the GNU Lesser General Public License
17    along with PulseAudio; if not, see <http://www.gnu.org/licenses/>.
18***/
19
20#ifdef HAVE_CONFIG_H
21#include <config.h>
22#endif
23
24#include <stdio.h>
25#include <unistd.h>
26#include <stdlib.h>
27#include <errno.h>
28#include <stdlib.h>
29#include <sys/types.h>
30
31#include <systemd/sd-login.h>
32
33#include <pulse/xmalloc.h>
34
35#include <pulsecore/module.h>
36#include <pulsecore/log.h>
37#include <pulsecore/hashmap.h>
38#include <pulsecore/idxset.h>
39#include <pulsecore/modargs.h>
40
41PA_MODULE_AUTHOR("Lennart Poettering");
42PA_MODULE_DESCRIPTION("Create a client for each login session of this user");
43PA_MODULE_VERSION(PACKAGE_VERSION);
44PA_MODULE_LOAD_ONCE(true);
45
46static const char* const valid_modargs[] = {
47    NULL
48};
49
50struct session {
51    char *id;
52    pa_client *client;
53};
54
55struct userdata {
56    pa_module *module;
57    pa_core *core;
58    pa_hashmap *sessions, *previous_sessions;
59    sd_login_monitor *monitor;
60    pa_io_event *io;
61};
62
63static int add_session(struct userdata *u, const char *id) {
64    struct session *session;
65    pa_client_new_data data;
66
67    session = pa_xnew(struct session, 1);
68    session->id = pa_xstrdup(id);
69
70    pa_client_new_data_init(&data);
71    data.module = u->module;
72    data.driver = __FILE__;
73    pa_proplist_setf(data.proplist, PA_PROP_APPLICATION_NAME, "Login Session %s", id);
74    pa_proplist_sets(data.proplist, "systemd-login.session", id);
75    session->client = pa_client_new(u->core, &data);
76    pa_client_new_data_done(&data);
77
78    if (!session->client) {
79        pa_xfree(session->id);
80        pa_xfree(session);
81        return -1;
82    }
83
84    pa_hashmap_put(u->sessions, session->id, session);
85
86    pa_log_debug("Added new session %s", id);
87
88    /* Positive exit_idle_time is only useful when we have no session tracking
89     * capability, so we can set it to 0 now that we have detected a session.
90     * The benefit of setting exit_idle_time to 0 is that pulseaudio will exit
91     * immediately when the session ends. That in turn is useful, because some
92     * systems (those that use pam_systemd but don't use systemd for managing
93     * pulseaudio) clean $XDG_RUNTIME_DIR on logout, but fail to terminate all
94     * services that depend on the files in $XDG_RUNTIME_DIR. The directory
95     * contains our sockets, and if the sockets are removed without terminating
96     * pulseaudio, a quick relogin will likely cause trouble, because a new
97     * instance will be spawned while the old instance is still running. */
98    if (u->core->exit_idle_time > 0)
99        pa_core_set_exit_idle_time(u->core, 0);
100
101    return 0;
102}
103
104static void free_session(struct session *session) {
105    pa_assert(session);
106
107    pa_log_debug("Removing session %s", session->id);
108
109    pa_client_free(session->client);
110    pa_xfree(session->id);
111    pa_xfree(session);
112}
113
114static int get_session_list(struct userdata *u) {
115    int r;
116    char **sessions;
117    pa_hashmap *h;
118    struct session *o;
119
120    pa_assert(u);
121
122    r = sd_uid_get_sessions(getuid(), 0, &sessions);
123    if (r < 0)
124        return -1;
125
126    /* We copy all sessions that still exist from one hashmap to the
127     * other and then flush the remaining ones */
128
129    h = u->previous_sessions;
130    u->previous_sessions = u->sessions;
131    u->sessions = h;
132
133    if (sessions) {
134        char **s;
135
136        /* Note that the sessions array is allocated with libc's
137         * malloc()/free() calls, hence do not use pa_xfree() to free
138         * this here. */
139
140        for (s = sessions; *s; s++) {
141            o = pa_hashmap_remove(u->previous_sessions, *s);
142            if (o)
143                pa_hashmap_put(u->sessions, o->id, o);
144            else
145                add_session(u, *s);
146
147            free(*s);
148        }
149
150        free(sessions);
151    }
152
153    pa_hashmap_remove_all(u->previous_sessions);
154
155    return 0;
156}
157
158static void monitor_cb(
159        pa_mainloop_api*a,
160        pa_io_event* e,
161        int fd,
162        pa_io_event_flags_t events,
163        void *userdata) {
164
165    struct userdata *u = userdata;
166
167    pa_assert(u);
168
169    sd_login_monitor_flush(u->monitor);
170    get_session_list(u);
171}
172
173int pa__init(pa_module *m) {
174    struct userdata *u = NULL;
175    pa_modargs *ma;
176    sd_login_monitor *monitor = NULL;
177    int r;
178
179    pa_assert(m);
180
181    /* If we are not actually running logind become a NOP */
182    if (access("/run/systemd/seats/", F_OK) < 0)
183        return 0;
184
185    ma = pa_modargs_new(m->argument, valid_modargs);
186    if (!ma) {
187        pa_log("Failed to parse module arguments");
188        goto fail;
189    }
190
191    r = sd_login_monitor_new("session", &monitor);
192    if (r < 0) {
193        pa_log("Failed to create session monitor: %s", strerror(-r));
194        goto fail;
195    }
196
197    m->userdata = u = pa_xnew0(struct userdata, 1);
198    u->core = m->core;
199    u->module = m;
200    u->sessions = pa_hashmap_new_full(pa_idxset_string_hash_func, pa_idxset_string_compare_func, NULL, (pa_free_cb_t) free_session);
201    u->previous_sessions = pa_hashmap_new_full(pa_idxset_string_hash_func, pa_idxset_string_compare_func, NULL, (pa_free_cb_t) free_session);
202    u->monitor = monitor;
203
204    u->io = u->core->mainloop->io_new(u->core->mainloop, sd_login_monitor_get_fd(monitor), PA_IO_EVENT_INPUT, monitor_cb, u);
205
206    if (get_session_list(u) < 0)
207        goto fail;
208
209    pa_modargs_free(ma);
210
211    return 0;
212
213fail:
214    if (ma)
215        pa_modargs_free(ma);
216
217    pa__done(m);
218
219    return -1;
220}
221
222void pa__done(pa_module *m) {
223    struct userdata *u;
224
225    pa_assert(m);
226
227    u = m->userdata;
228    if (!u)
229        return;
230
231    if (u->sessions) {
232        pa_hashmap_free(u->sessions);
233        pa_hashmap_free(u->previous_sessions);
234    }
235
236    if (u->io)
237        m->core->mainloop->io_free(u->io);
238
239    if (u->monitor)
240        sd_login_monitor_unref(u->monitor);
241
242    pa_xfree(u);
243}
244