player.c

linux下MPEG播放器

    player->control = PLAYER_CONTROL_REPLAY;
    flow = MAD_FLOW_STOP;

    /* fall through */

  case KEY_PAUSE:
    stop_audio(player, stopped);
    message(" --%s--", stopped ? _("Stopped") : _("Paused"));

    command = readkey(1);

    message("");

    if (command == -1)
      return MAD_FLOW_BREAK;

    if (command != KEY_PAUSE)
      goto again;

    break;

  case KEY_FORWARD:
  case KEY_CTRL('n'):
  case '>':
    player->control = PLAYER_CONTROL_NEXT;
    goto stop;

  case KEY_BACK:
  case KEY_CTRL('p'):
  case '<':
    {
      mad_timer_t threshold;

      mad_timer_set(&threshold, 4, 0, 0);

      player->control =
	(stopped ||
	 mad_timer_compare(player->stats.play_timer, threshold) < 0) ?
	PLAYER_CONTROL_PREVIOUS : PLAYER_CONTROL_REPLAY;
    }
    goto stop;

  case KEY_QUIT:
  case KEY_CTRL('c'):
  case 'Q':
    player->control = PLAYER_CONTROL_STOP;
    goto stop;

  case KEY_INFO:
  case '?':
    if (player->verbosity <= 0) {
      show_status(&player->stats, 0, player->input.path, 1);
      message("\n");
    }
    break;

  case KEY_TIME:
    if (player->verbosity > 0) {
      char const *label = 0;

      switch (player->stats.show) {
      case STATS_SHOW_OVERALL:
	player->stats.show = STATS_SHOW_REMAINING;
	label = N_("[Current Time Remaining]");
	break;

      case STATS_SHOW_REMAINING:
	player->stats.show = STATS_SHOW_CURRENT;
	label = N_("[Current Time]");
	break;

      case STATS_SHOW_CURRENT:
	player->stats.show = STATS_SHOW_OVERALL;
	label = N_("[Overall Time]");
	break;
      }

      show_status(&player->stats, 0, gettext(label), 1);
    }
    break;

  case KEY_GAINDECR:
  case KEY_GAININCR:
  case KEY_GAINZERO:
  case KEY_GAININFO:
    {
      double db;

      switch (command) {
      case KEY_GAINDECR:
	db = set_gain(player, GAIN_ATTAMP | GAIN_RELATIVE, -0.5);
	break;

      case KEY_GAININCR:
	db = set_gain(player, GAIN_ATTAMP | GAIN_RELATIVE, +0.5);
	break;

      case KEY_GAINZERO:
	db = set_gain(player, GAIN_ATTAMP, 0);
	break;

      default:
	db = set_gain(player, 0, 0);
	break;
      }

      if (player->verbosity > 0) {
	static char status[15];

	sprintf(status, "%+.1f dB gain", db);
	show_status(&player->stats, 0, status, 1);
      }
    }
    break;
  }

  return flow;

 stop:
  stop_audio(player, 1);
  return MAD_FLOW_STOP;
}
# endif

/*
 * NAME:	addfilter()
 * DESCRIPTION:	insert a filter at the beginning of the filter chain
 */
static
int addfilter(struct player *player, filter_func_t *func, void *data)
{
  struct filter *filter;

  filter = filter_new(func, data, player->output.filters);
  if (filter == 0)
    return -1;

  player->output.filters = filter;

  return 0;
}

/*
 * NAME:	setup_filters()
 * DESCRIPTION:	create output filters
 */
static
int setup_filters(struct player *player)
{
  /* filters must be added in reverse order */

# if defined(EXPERIMENTAL)
  if ((player->options & PLAYER_OPTION_EXTERNALMIX) &&
      addfilter(player, mixer_filter, stdout) == -1)
    return -1;

  if ((player->options & PLAYER_OPTION_EXPERIMENTAL) &&
      addfilter(player, experimental_filter, 0) == -1)
    return -1;
# endif

  if ((player->options & PLAYER_OPTION_FADEIN) &&
      addfilter(player, fadein_filter, player) == -1)
    return -1;

  addfilter(player, gain_filter, &player->output.gain);

  if (player->output.select == PLAYER_CHANNEL_MONO &&
      addfilter(player, mono_filter, player) == -1)
    return -1;

# if defined(USE_TTY)
  if ((player->options & PLAYER_OPTION_TTYCONTROL) &&
      addfilter(player, tty_filter, player) == -1)
    return -1;
# endif

  return 0;
}

# if defined(USE_TTY) && !defined(_WIN32)
/*
 * NAME:	restore_tty()
 * DESCRIPTION:	revert to previous terminal settings
 */
static
int restore_tty(int interrupt)
{
  struct termios tty;
  struct sigaction action;
  int result = 0;

  if (tcgetattr(tty_fd, &tty) == 0 &&
      tcsetattr(tty_fd, interrupt ? TCSAFLUSH : TCSADRAIN,
		&save_tty) == -1) {
    if (!interrupt)
      error("tty", ":tcsetattr");
    result = -1;
  }

  save_tty = tty;

  if (sigaction(SIGINT, 0, &action) == 0 &&
      sigaction(SIGINT, &save_sigint, 0) == -1) {
    if (!interrupt)
      error("tty", ":sigaction(SIGINT)");
    result = -1;
  }

  save_sigint = action;

  if (sigaction(SIGTSTP, 0, &action) == 0 &&
      sigaction(SIGTSTP, &save_sigtstp, 0) == -1) {
    if (!interrupt)
      error("tty", ":sigaction(SIGTSTP)");
    result = -1;
  }

  save_sigtstp = action;

  if (!interrupt) {
    if (close(tty_fd) == -1) {
      error("tty", ":close");
      result = -1;
    }

    tty_fd = -1;
  }

  return result;
}

/*
 * NAME:	signal_handler()
 * DESCRIPTION:	restore tty state after software interrupt
 */
static
void signal_handler(int signal)
{
  static struct sigaction save_sigcont;

  /* restore tty state and previous signal actions */

  restore_tty(1);

  /* handle SIGCONT after SIGTSTP */

  switch (signal) {
  case SIGTSTP:
    {
      struct sigaction action;

      sigaction(SIGCONT, 0, &save_sigcont);

      action = save_sigcont;
      action.sa_handler = signal_handler;
      sigemptyset(&action.sa_mask);
      sigaddset(&action.sa_mask, SIGTSTP);
      sigaddset(&action.sa_mask, SIGINT);
      action.sa_flags = 0;

      sigaction(SIGCONT, &action, 0);
    }
    break;

  case SIGCONT:
    sigaction(SIGCONT, &save_sigcont, 0);
    on_same_line = 0;  /* redraw status line */
    break;
  }

  /* re-send signal, which is currently blocked */

  kill(getpid(), signal);

  /* return to previous thread, which should immediately receive the signal */

  return;
}

/*
 * NAME:	setup_tty()
 * DESCRIPTION:	change terminal parameters and signal handlers
 */
static
int setup_tty(void)
{
  struct termios tty;
  struct sigaction action;

  /* open controlling terminal */

  tty_fd = open(TTY_DEVICE, O_RDONLY);
  if (tty_fd == -1) {
    error("tty", ":", TTY_DEVICE);
    return -1;
  }

  /* save current terminal and signal settings */

  if (tcgetattr(tty_fd, &save_tty) == -1) {
    error("tty", ":tcgetattr");
    return -1;
  }

  if (sigaction(SIGTSTP, 0, &save_sigtstp) == -1) {
    error("tty", ":sigaction(SIGTSTP)");
    return -1;
  }

  if (sigaction(SIGINT, 0, &save_sigint) == -1) {
    error("tty", ":sigaction(SIGINT)");
    return -1;
  }

  /* catch SIGTSTP and SIGINT so the tty state can be restored */

  action = save_sigtstp;
  action.sa_handler = signal_handler;
  sigemptyset(&action.sa_mask);
  sigaddset(&action.sa_mask, SIGINT);
# if 0  /* on some systems (Mac OS X) this remains masked upon continue (?!) */
  sigaddset(&action.sa_mask, SIGCONT);
# endif
  action.sa_flags = 0;

  if (sigaction(SIGTSTP, &action, 0) == -1) {
    error("tty", ":sigaction(SIGTSTP)");
    goto fail;
  }

  action = save_sigint;
  action.sa_handler = signal_handler;
  sigemptyset(&action.sa_mask);
  sigaddset(&action.sa_mask, SIGTSTP);
  sigaddset(&action.sa_mask, SIGCONT);
  action.sa_flags = 0;

  if (sigaction(SIGINT, &action, 0) == -1) {
    error("tty", ":sigaction(SIGINT)");
    goto fail;
  }

  /* turn off echo and canonical mode */

  tty = save_tty;

  tty.c_lflag &= ~(ECHO | ICANON);

  /* set VMIN = VTIME = 0 so read() always returns immediately */

  tty.c_cc[VMIN]  = 0;
  tty.c_cc[VTIME] = 0;

  if (tcsetattr(tty_fd, TCSAFLUSH, &tty) == -1) {
    error("tty", ":tcsetattr");
    goto fail;
  }

  return 0;

 fail:
  sigaction(SIGINT,  &save_sigint,  0);
  sigaction(SIGTSTP, &save_sigtstp, 0);
  return -1;
}
# endif

/*
 * NAME:	silence()
 * DESCRIPTION:	output silence for a period of time
 */
static
int silence(struct player *player, mad_timer_t duration, char const *label)
{
  union audio_control control;
  unsigned int nchannels, speed, nsamples;
  mad_fixed_t *samples;
  mad_timer_t unit;
  int result = 0;

  audio_control_init(&control, AUDIO_COMMAND_CONFIG);
  control.config.channels = 2;
  control.config.speed    = 44100;

  if (player->output.command(&control) == -1) {
    error("audio", audio_error);
    return -1;
  }

  nchannels = control.config.channels;
  speed     = control.config.speed;
  nsamples  = speed > MAX_NSAMPLES ? MAX_NSAMPLES : speed;

  player->output.channels_in  = nchannels;
  player->output.channels_out = nchannels;
  player->output.speed_in     = speed;
  player->output.speed_out    = speed;

  samples = calloc(nsamples, sizeof(mad_fixed_t));
  if (samples == 0) {
    error("silence", _("not enough memory to allocate sample buffer"));
    return -1;
  }

  audio_control_init(&control, AUDIO_COMMAND_PLAY);
  control.play.nsamples   = nsamples;
  control.play.samples[0] = samples;
  control.play.samples[1] = (nchannels == 2) ? samples : 0;
  control.play.mode       = player->output.mode;
  control.play.stats      = &player->stats.audio;

  mad_timer_set(&unit, 0, nsamples, speed);

  for (mad_timer_negate(&duration);
       mad_timer_sign(duration) < 0;
       mad_timer_add(&duration, unit)) {
    if (mad_timer_compare(unit, mad_timer_abs(duration)) > 0) {
      unit = mad_timer_abs(duration);
      control.play.nsamples = mad_timer_fraction(unit, speed);
    }

# if defined(USE_TTY)
    if ((player->options & PLAYER_OPTION_TTYCONTROL) &&
	tty_filter(player, 0) != MAD_FLOW_CONTINUE)
      goto fail;
# endif

    if (player->output.command(&control) == -1) {
      error("audio", audio_error);
      goto fail;
    }

    mad_timer_add(&player->stats.global_timer, unit);

    if (player->verbosity > 0)
      show_status(&player->stats, 0, label, 0);
  }

  if (0) {
  fail:
    result = -1;
  }

  free(samples);

  return result;
}

/*
 * NAME:	player->run()
 * DESCRIPTION:	begin playback
 */
int player_run(struct player *player, int argc, char const *argv[])
{
  int result = 0;
  union audio_control control;

  player->playlist.entries = argv;
  player->playlist.length  = argc;

  /* set up terminal settings */

# if defined(USE_TTY) && !defined(_WIN32)
  if ((player->options & PLAYER_OPTION_TTYCONTROL) &&
      setup_tty() == -1)
    player->options &= ~PLAYER_OPTION_TTYCONTROL;
# endif

  /* initialize ancillary data output file */

  if (player->ancillary.path) {
    if (player->output.path &&
	strcmp(player->ancillary.path, player->output.path) == 0) {
      error("output", _("ancillary and audio output have same path"));
      goto fail;
    }

    if (strcmp(player->ancillary.path, "-") == 0)
      player->ancillary.file = stdout;
    else {
      player->ancillary.file = fopen(player->ancillary.path, "wb");
      if (player->ancillary.file == 0) {
	error("ancillary", ":", player->ancillary.path);
	goto fail;
      }
    }
  }

  /* set up filters */

  if (setup_filters(player) == -1) {
    error("filter", _("not enough memory to allocate filters"));
    goto fail;
  }

  set_gain(player, 0, 0);

  /* initialize audio */

  if (player->output.command) {
    audio_control_init(&control, AUDIO_COMMAND_INIT);
    control.init.path = player->output.path;

    if (player->output.command(&control) == -1) {
      error("audio", audio_error, control.init.path);
      goto fail;
    }

    if ((player->options & PLAYER_OPTION_SKIP) &&
	mad_timer_sign(player->global_start) < 0) {
      player->stats.global_timer = player->global_start;

      if (silence(player, mad_timer_abs(player->global_start),
		  _("lead-in")) == -1)
	result = -1;
    }
  }

  /* run playlist */

  if (result == 0)
    result = play_all(player);

  /* drain and close audio */

  if (player->output.command) {
    audio_control_init(&control, AUDIO_COMMAND_FINISH);

    if (player->output.command(&control) == -1) {
      error("audio", audio_error);
      goto fail;
    }
  }

  if (0) {
  fail:
    result = -1;
  }

  /* drain and close ancillary data output file */

  if (player->ancillary.file) {
    if (player->ancillary.length) {
      if (fputc(player->ancillary.buffer << (8 - player->ancillary.length),
		player->ancillary.file) == EOF &&
	  result == 0) {
	error("ancillary", ":fputc");
	result = -1;
      }

      player->ancillary.length = 0;
    }

    if (player->ancillary.file != stdout &&
	fclose(player->ancillary.file) == EOF &&
	result == 0) {
      error("ancillary", ":fclose");
      result = -1;
    }

    player->ancill