<?php
// Run an external 'MRTG-compatible' script, and return it's values
// TARGET !/usr/local/bin/qmailmrtg7 t /var/log/qmail

// MRTG Target scripts return 4 lines of text as output:
//    'Input' value - interpreted as a byte count (so multiplied by 8)
//    'Output' value - interpreted as a byte count (so multiplied by 8)
//    'uptime' as a string
//    'name of targer' as a string
// we ignore the last two

// NOTE: Obviously, if you allow anyone to create maps, you are
//       allowing them to run ANY COMMAND as the user that runs
//       weathermap, by using this plugin. This might not be a
//       good thing.

//       If you want to allow only one command, consider making
//       your own datasource plugin which only runs that one command.

class WeatherMapDataSource_external extends WeatherMapDataSource
{
    function Recognise($targetstring)
    {
        if (preg_match("/^!(.*)$/", $targetstring, $matches)) {
            return true;
        } else {
            return false;
        }
    }

    function ReadData($targetstring, &$map, &$item)
    {
        $data[IN] = null;
        $data[OUT] = null;
        $data_time = 0;

        if (preg_match("/^!(.*)$/", $targetstring, $matches)) {
            $command = $matches[1];

            wm_debug("ExternalScript ReadData: Running $command\n");

            // run the command here
            if (($pipe = popen($command, "r")) === false) {
                wm_warn("ExternalScript ReadData: Failed to run external script. [WMEXT01]\n");
            } else {
                $i = 0;

                while (($i < 5) && !feof($pipe)) {
                    $lines[$i++] = fgets($pipe, 1024);
                }
                pclose($pipe);

                if ($i === 5) {
                    $data[IN] = floatval($lines[0]);
                    $data[OUT] = floatval($lines[1]);

                    $item->add_hint('external_line1', $lines[0]);
                    $item->add_hint('external_line2', $lines[1]);
                    $item->add_hint('external_line3', $lines[2]);
                    $item->add_hint('external_line4', $lines[3]);
                    $data_time = time();
                } else {
                    wm_warn("ExternalScript ReadData: Not enough lines read from external script ($i read, 4 expected) [WMEXT02]\n");
                }
            }
        }

        wm_debug( sprintf("ExternalScript ReadData: Returning (%s, %s, %s)\n",
		        string_or_null($data[IN]),
		        string_or_null($data[OUT]),
		        $data_time
        	));
            
        return (array (
            $data[IN],
            $data[OUT],
            $data_time
        ));
    }
}

// vim:ts=4:sw=4:

?>