[asterisk-dev] "56k" in dahdi/system.conf [was Re: [svn-commits] mattf: tools/trunk r4818 - /tools/trunk/dahdi_cfg.c]

[Tzafrir Cohen]

Hi

On Sun, Aug 24, 2008 at 05:54:12AM -0000, SVN commits to the Digium repositories wrote:
> Author: mattf
> Date: Sun Aug 24 00:54:11 2008
> New Revision: 4818
> 
> URL: http://svn.digium.com/view/dahdi?view=rev&rev=4818
> Log:
> Add support for 56 KB HDLC as well as selectable rate in system.conf
> 
> Modified:
>     tools/trunk/dahdi_cfg.c

What does it mean? Where should it be used?

Something in the lines of:

(immedietly following the description of dacsrbs)

# 56k::
#   Set a D-channel (which has already been set above as 'bchan',
#   'hardhdlc' or 'nethdlc') to use 56kbps HDLC.

The name "56k" sounds strange and and maybe not descriptive enough.

Also:

> 
> Modified: tools/trunk/dahdi_cfg.c
> URL: http://svn.digium.com/view/dahdi/tools/trunk/dahdi_cfg.c?view=diff&rev=4818&r1=4817&r2=4818
> ==============================================================================
> --- tools/trunk/dahdi_cfg.c (original)
> +++ tools/trunk/dahdi_cfg.c Sun Aug 24 00:54:11 2008
> @@ -85,6 +85,8 @@
>  static const char *sig[DAHDI_MAX_CHANNELS];		/* Signalling */
>  
>  static int slineno[DAHDI_MAX_CHANNELS];	/* Line number where signalling specified */
> +
> +static int fiftysixkhdlc[DAHDI_MAX_CHANNELS];
>  
>  static int spans=0;
>  
> @@ -646,6 +648,49 @@
>  	return 0;
>  }
>  
> +static int setfiftysixkhdlc(char *keyword, char *args)
> +{
> +	int res;
> +
> +	res = apply_channels(fiftysixkhdlc, args);
> +	if (res <= 0)
> +		return -1;
> +
> +	return 0;
> +}
> +
> +static void apply_fiftysix(void)
> +{
> +	int x;
> +	int rate;
> +	int chanfd;
> +
> +	for (x = 1; x < DAHDI_MAX_CHANNELS; x++) {
> +		chanfd = open("/dev/dahdi/channel", O_RDWR);
> +		if (chanfd == -1) {
> +			fprintf(stderr, "Couldn't open /dev/zap/channel\n");
> +			exit(-1);
> +		}
> +
> +		if (ioctl(chanfd, DAHDI_SPECIFY, &x)) {
> +			continue;
> +		}
> +
> +		if (fiftysixkhdlc[x]) {
> +			printf("Setting channel %d to 56K mode (only valid on HDLC channels)\n", x);
> +			rate = 56;
> +		} else {
> +			rate = 64;
> +		}
> +
> +		if (ioctl(chanfd, DAHDI_HDLC_RATE, &rate)) {
> +			fprintf(stderr, "Error setting HDLC rate\n");
> +			exit(-1);
> +		}
> +		close(chanfd);
> +	}
> +}
> +
>  static int setechocan(char *keyword, char *args)
>  {
>  	int res;
> @@ -1310,6 +1355,7 @@
>  	{ "channel", rad_chanconfig },
>  	{ "channels", rad_chanconfig },
>  	{ "echocanceller", setechocan },
> +	{ "56k", setfiftysixkhdlc },
>  };
>  
>  static char *readline()

Here we are in the end of main()

> @@ -1586,5 +1632,6 @@
>  		fprintf(stderr, "\n%d error(s) detected\n\n", errcnt);
>  		exit(1);
>  	}
> +	apply_fiftysix();
>  	exit(0);
>  }

Why run this is a separate loop? Re-open /dev/dahdi/channel regardless
of whether this directive was ever used.

The loop above for applying configuration to channels is indeed not a
pretty sight. 3 nesting levels can be easily removed from it (OK to
commit that now?)

-- 
               Tzafrir Cohen
icq#16849755              jabber:tzafrir.cohen at xorcom.com
+972-50-7952406           mailto:tzafrir.cohen at xorcom.com
http://www.xorcom.com  iax:guest at local.xorcom.com/tzafrir