[alsa-devel] [PATCH - pcm_jack plugin 1/1] Restore PID to jack client name when not specified explicitly

[Takashi Iwai]

At Fri,  8 Aug 2014 14:31:06 -0700,
branan at gmail.com wrote:
> 
> From: Branan Purvine-Riley <branan at gmail.com>
> 
> Commit 14190cd8 added a facility to explicitly name Jack clients with
> a 'name' option, but did so in a way that was not fully
> backwards-compatible with older versions of the alsa-plugins. There
> were two issues:
> 
> 1. Re-using the magical "name" variable, which comes preloaded with
> the name of the PCM
> 
> 2. The code assumed snd_config_get_string sets a variable to NULL if
> the config entry does not exist. Instead, this function leaves the
> variable unchanged.
> 
> The result of these two errors meant that the PCM name would be
> treated as if it were a user-defined name, and the old code which
> embedded the PID would never be run
> 
> This code uses a completely new variable to store the explicitly-set
> client name, so that the two code paths no longer collide.
> 
> Signed-off-by: Branan Purvine-Riley <branan at gmail.com>

Thanks, applied.


Takashi

> 
> diff --git a/jack/pcm_jack.c b/jack/pcm_jack.c
> index f5b7129..33f87b1 100644
> --- a/jack/pcm_jack.c
> +++ b/jack/pcm_jack.c
> @@ -372,6 +372,7 @@ static int make_nonblock(int fd)
>  }
>  
>  static int snd_pcm_jack_open(snd_pcm_t **pcmp, const char *name,
> +			     const char* client_name,
>  			     snd_config_t *playback_conf,
>  			     snd_config_t *capture_conf,
>  			     snd_pcm_stream_t stream, int mode)
> @@ -405,14 +406,14 @@ static int snd_pcm_jack_open(snd_pcm_t **pcmp, const char *name,
>  		return -EINVAL;
>  	}
>  
> -	if (name == NULL)
> +	if (client_name == NULL)
>  		err = snprintf(jack_client_name, sizeof(jack_client_name),
>  			       "alsa-jack.%s%s.%d.%d", name,
>  			       stream == SND_PCM_STREAM_PLAYBACK ? "P" : "C",
>  			       getpid(), num++);
>  	else
>  		err = snprintf(jack_client_name, sizeof(jack_client_name),
> -			       "%s", name);
> +			       "%s", client_name);
>  
>  	if (err >= (int)sizeof(jack_client_name)) {
>  		fprintf(stderr, "%s: WARNING: JACK client name '%s' truncated to %d characters, might not be unique\n",
> @@ -470,6 +471,7 @@ SND_PCM_PLUGIN_DEFINE_FUNC(jack)
>  	snd_config_iterator_t i, next;
>  	snd_config_t *playback_conf = NULL;
>  	snd_config_t *capture_conf = NULL;
> +	const char* client_name = NULL;
>  	int err;
>  	
>  	snd_config_for_each(i, next, conf) {
> @@ -480,7 +482,7 @@ SND_PCM_PLUGIN_DEFINE_FUNC(jack)
>  		if (strcmp(id, "comment") == 0 || strcmp(id, "type") == 0 || strcmp(id, "hint") == 0)
>  			continue;
>  		if (strcmp(id, "name") == 0) {
> -			snd_config_get_string(n, &name);
> +			snd_config_get_string(n, &client_name);
>  			continue;
>  		}
>  		if (strcmp(id, "playback_ports") == 0) {
> @@ -503,7 +505,7 @@ SND_PCM_PLUGIN_DEFINE_FUNC(jack)
>  		return -EINVAL;
>  	}
>  
> -	err = snd_pcm_jack_open(pcmp, name, playback_conf, capture_conf, stream, mode);
> +	err = snd_pcm_jack_open(pcmp, name, client_name, playback_conf, capture_conf, stream, mode);
>  
>  	return err;
>  }
> -- 
> 2.0.4
>