modules/audio_output/vlcpulse.c

   1 /**
   2  * \file vlcpulse.c
   3  * \brief PulseAudio support library for LibVLC plugins
   4  */
   5 /*****************************************************************************
   6  * Copyright (C) 2009-2011 Rémi Denis-Courmont
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms of the GNU Lesser General Public License as published by
  10  * the Free Software Foundation; either version 2.1 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  16  * GNU Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public License
  19  * along with this program; if not, write to the Free Software Foundation,
  20  * Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
  21  *****************************************************************************/
  22
  23 #ifdef HAVE_CONFIG_H
  24 # include "config.h"
  25 #endif
  26
  27 #include <vlc_common.h>
  28 #include <pulse/pulseaudio.h>
  29
  30 #include "audio_output/vlcpulse.h"
  31 #include <assert.h>
  32 #include <stdlib.h>
  33 #include <locale.h>
  34 #include <unistd.h>
  35 #include <pwd.h>
  36
  37 const char vlc_module_name[] = "vlcpulse";
  38
  39 #undef vlc_pa_error
  40 void vlc_pa_error (vlc_object_t *obj, const char *msg, pa_context *ctx)
  41 {
  42     msg_Err (obj, "%s: %s", msg, pa_strerror (pa_context_errno (ctx)));
  43 }
  44
  45 static void context_state_cb (pa_context *ctx, void *userdata)
  46 {
  47     pa_threaded_mainloop *mainloop = userdata;
  48
  49     switch (pa_context_get_state(ctx))
  50     {
  51         case PA_CONTEXT_READY:
  52         case PA_CONTEXT_FAILED:
  53         case PA_CONTEXT_TERMINATED:
  54             pa_threaded_mainloop_signal (mainloop, 0);
  55         default:
  56             break;
  57     }
  58 }
  59
  60 static bool context_wait (pa_context *ctx, pa_threaded_mainloop *mainloop)
  61 {
  62     pa_context_state_t state;
  63
  64     while ((state = pa_context_get_state (ctx)) != PA_CONTEXT_READY)
  65     {
  66         if (state == PA_CONTEXT_FAILED || state == PA_CONTEXT_TERMINATED)
  67             return -1;
  68         pa_threaded_mainloop_wait (mainloop);
  69     }
  70     return 0;
  71 }
  72
  73 static void context_event_cb(pa_context *c, const char *name, pa_proplist *pl,
  74                              void *userdata)
  75 {
  76     vlc_object_t *obj = userdata;
  77
  78     msg_Warn (obj, "unhandled context event \"%s\"", name);
  79     (void) c;
  80     (void) pl;
  81 }
  82
  83 /**
  84  * Initializes the PulseAudio main loop and connects to the PulseAudio server.
  85  * @return a PulseAudio context on success, or NULL on error
  86  */
  87 pa_context *vlc_pa_connect (vlc_object_t *obj, pa_threaded_mainloop **mlp)
  88 {
  89     msg_Dbg (obj, "using library version %s", pa_get_library_version ());
  90     msg_Dbg (obj, " (compiled with version %s, protocol %u)",
  91              pa_get_headers_version (), PA_PROTOCOL_VERSION);
  92
  93     /* Initialize main loop */
  94     pa_threaded_mainloop *mainloop = pa_threaded_mainloop_new ();
  95     if (unlikely(mainloop == NULL))
  96         return NULL;
  97
  98     if (pa_threaded_mainloop_start (mainloop) < 0)
  99     {
 100         pa_threaded_mainloop_free (mainloop);
 101         return NULL;
 102     }
 103
 104     /* Fill in context (client) properties */
 105     char *ua = var_InheritString (obj, "user-agent");
 106     pa_proplist *props = pa_proplist_new ();
 107     if (likely(props != NULL))
 108     {
 109         char *str;
 110
 111         if (ua != NULL)
 112             pa_proplist_sets (props, PA_PROP_APPLICATION_NAME, ua);
 113
 114         str = var_InheritString (obj, "app-id");
 115         if (str != NULL)
 116         {
 117             pa_proplist_sets (props, PA_PROP_APPLICATION_ID, str);
 118             free (str);
 119         }
 120         str = var_InheritString (obj, "app-version");
 121         if (str != NULL)
 122         {
 123             pa_proplist_sets (props, PA_PROP_APPLICATION_VERSION, str);
 124             free (str);
 125         }
 126         str = var_InheritString (obj, "app-icon-name");
 127         if (str != NULL)
 128         {
 129             pa_proplist_sets (props, PA_PROP_APPLICATION_ICON_NAME, str);
 130             free (str);
 131         }
 132         //pa_proplist_sets (props, PA_PROP_APPLICATION_LANGUAGE, _("C"));
 133         pa_proplist_sets (props, PA_PROP_APPLICATION_LANGUAGE,
 134                           setlocale (LC_MESSAGES, NULL));
 135
 136         pa_proplist_setf (props, PA_PROP_APPLICATION_PROCESS_ID, "%lu",
 137                           (unsigned long) getpid ());
 138         //pa_proplist_sets (props, PA_PROP_APPLICATION_PROCESS_BINARY,
 139         //                  PACKAGE_NAME);
 140
 141         for (size_t max = sysconf (_SC_GETPW_R_SIZE_MAX), len = max % 1024 + 1024;
 142              len < max; len += 1024)
 143         {
 144             struct passwd pwbuf, *pw;
 145             char buf[len];
 146
 147             if (getpwuid_r (getuid (), &pwbuf, buf, sizeof (buf), &pw) == 0)
 148             {
 149                 if (pw != NULL)
 150                     pa_proplist_sets (props, PA_PROP_APPLICATION_PROCESS_USER,
 151                                       pw->pw_name);
 152                 break;
 153             }
 154         }
 155
 156         for (size_t max = sysconf (_SC_HOST_NAME_MAX), len = max % 1024 + 1024;
 157              len < max; len += 1024)
 158         {
 159             char hostname[len];
 160
 161             if (gethostname (hostname, sizeof (hostname)) == 0)
 162             {
 163                 pa_proplist_sets (props, PA_PROP_APPLICATION_PROCESS_HOST,
 164                                   hostname);
 165                 break;
 166             }
 167         }
 168
 169         const char *session = getenv ("XDG_SESSION_COOKIE");
 170         if (session != NULL)
 171         {
 172             pa_proplist_setf (props, PA_PROP_APPLICATION_PROCESS_MACHINE_ID,
 173                               "%.32s", session); /* XXX: is this valid? */
 174             pa_proplist_sets (props, PA_PROP_APPLICATION_PROCESS_SESSION_ID,
 175                               session);
 176         }
 177     }
 178
 179     /* Connect to PulseAudio daemon */
 180     pa_context *ctx;
 181     pa_mainloop_api *api;
 182
 183     pa_threaded_mainloop_lock (mainloop);
 184     api = pa_threaded_mainloop_get_api (mainloop);
 185     ctx = pa_context_new_with_proplist (api, ua, props);
 186     free (ua);
 187     if (props != NULL)
 188         pa_proplist_free (props);
 189     if (unlikely(ctx == NULL))
 190         goto fail;
 191
 192     pa_context_set_state_callback (ctx, context_state_cb, mainloop);
 193     pa_context_set_event_callback (ctx, context_event_cb, obj);
 194     if (pa_context_connect (ctx, NULL, 0, NULL) < 0
 195      || context_wait (ctx, mainloop))
 196     {
 197         vlc_pa_error (obj, "PulseAudio server connection failure", ctx);
 198         pa_context_unref (ctx);
 199         goto fail;
 200     }
 201     msg_Dbg (obj, "connected %s to %s as client #%"PRIu32,
 202              pa_context_is_local (ctx) ? "locally" : "remotely",
 203              pa_context_get_server (ctx), pa_context_get_index (ctx));
 204     msg_Dbg (obj, "using protocol %"PRIu32", server protocol %"PRIu32,
 205              pa_context_get_protocol_version (ctx),
 206              pa_context_get_server_protocol_version (ctx));
 207
 208     pa_threaded_mainloop_unlock (mainloop);
 209     *mlp = mainloop;
 210     return ctx;
 211
 212 fail:
 213     pa_threaded_mainloop_unlock (mainloop);
 214     pa_threaded_mainloop_stop (mainloop);
 215     pa_threaded_mainloop_free (mainloop);
 216     return NULL;
 217 }
 218
 219 /**
 220  * Closes a connection to PulseAudio.
 221  */
 222 void vlc_pa_disconnect (vlc_object_t *obj, pa_context *ctx,
 223                         pa_threaded_mainloop *mainloop)
 224 {
 225     pa_threaded_mainloop_lock (mainloop);
 226     pa_context_disconnect (ctx);
 227     pa_context_set_event_callback (ctx, NULL, NULL);
 228     pa_context_set_state_callback (ctx, NULL, NULL);
 229     pa_context_unref (ctx);
 230     pa_threaded_mainloop_unlock (mainloop);
 231
 232     pa_threaded_mainloop_stop (mainloop);
 233     pa_threaded_mainloop_free (mainloop);
 234     (void) obj;
 235 }
 236
 237 /**
 238  * Frees a timer event.
 239  * \note Timer events can be created with pa_context_rttime_new().
 240  * \warning This function must be called from the mainloop,
 241  * or with the mainloop lock held.
 242  */
 243 void vlc_pa_rttime_free (pa_threaded_mainloop *mainloop, pa_time_event *e)
 244 {
 245     pa_mainloop_api *api = pa_threaded_mainloop_get_api (mainloop);
 246
 247     api->time_free (e);
 248 }
 249
 250 #undef vlc_pa_get_latency
 251 /**
 252  * Gets latency of a PulseAudio stream.
 253  * \return the latency or VLC_TS_INVALID on error.
 254  */
 255 mtime_t vlc_pa_get_latency(vlc_object_t *obj, pa_context *ctx, pa_stream *s)
 256 {
 257     /* NOTE: pa_stream_get_latency() will report 0 rather than negative latency
 258      * when the write index of a playback stream is behind its read index.
 259      * playback streams. So use the lower-level pa_stream_get_timing_info()
 260      * directly to obtain the correct write index and convert it to a time,
 261      * and compute the correct latency value by subtracting the stream (read)
 262      * time.
 263      *
 264      * On the read side, pa_stream_get_time() is used instead of
 265      * pa_stream_get_timing_info() for the sake of interpolation. */
 266     const pa_sample_spec *ss = pa_stream_get_sample_spec(s);
 267     const pa_timing_info *ti = pa_stream_get_timing_info(s);
 268
 269     if (ti == NULL) {
 270         msg_Dbg(obj, "no timing infos");
 271         return VLC_TS_INVALID;
 272     }
 273
 274     if (ti->write_index_corrupt) {
 275         msg_Dbg(obj, "write index corrupt");
 276         return VLC_TS_INVALID;
 277     }
 278
 279     pa_usec_t wt = pa_bytes_to_usec((uint64_t)ti->write_index, ss);
 280     pa_usec_t rt;
 281
 282     if (pa_stream_get_time(s, &rt)) {
 283         if (pa_context_errno(ctx) != PA_ERR_NODATA)
 284             vlc_pa_error(obj, "unknown time", ctx);
 285         return VLC_TS_INVALID;
 286     }
 287
 288     union { uint64_t u; int64_t s; } d;
 289     d.u = wt - rt;
 290     return d.s; /* non-overflowing unsigned to signed conversion */
 291 }