code.delx.au - monosys/blob - wifi-scan

   1 #!/usr/bin/env node
   2
   3 const {exec} = require('child_process');
   4
   5 function execAsync(command, opts) {
   6     return new Promise((resolve, reject) => {
   7         exec(command, opts, (error, stdout, stderr) => {
   8             if (error) {
   9                 reject(error);
  10             } else {
  11                 resolve({stdout, stderr});
  12             }
  13         });
  14     });
  15 }
  16
  17 function sleep(n) {
  18     return new Promise((resolve) => setTimeout(resolve, n));
  19 }
  20
  21 async function findInterface() {
  22     const {stdout} = await execAsync('iw dev');
  23     const lines = stdout.split('\n')
  24         .map((line) => line.trim())
  25         .filter((line) => line.startsWith('Interface '))
  26         .map((line) => line.split(' ')[1]);
  27     return lines[0];
  28 }
  29
  30 async function scanInterface(interface) {
  31     const {stdout} = await execAsync(`sudo iw dev ${interface} scan`);
  32
  33     const results = [];
  34     let partial = null;
  35
  36     for (let line of stdout.split('\n')) {
  37         if (line.startsWith('BSS ')) {
  38             finishPartial();
  39             partial = {};
  40             partial.bssid = line.match(/[a-z0-9:]+/)[0];
  41         }
  42
  43         line = line.trim()
  44         if (line.startsWith('SSID: ')) {
  45             partial.ssid = line.split(':')[1].trim();
  46         }
  47         if (line.startsWith('signal: ')) {
  48             partial.signal = line.split(':')[1].trim();
  49         }
  50         if (line.startsWith('DS Parameter set: channel')) {
  51             partial.channel = line.split(':')[1].trim();
  52         }
  53     }
  54
  55     function finishPartial() {
  56         if (!partial) {
  57             return;
  58         }
  59
  60         partial.ssid = partial.ssid || '';
  61         partial.channel = partial.channel || '';
  62
  63         const sortKey = [
  64             parseFloat(partial.signal),
  65             parseInt(partial.channel.split(' ')[1])
  66         ];
  67
  68         results.push([sortKey, partial]);
  69     }
  70
  71     return results
  72         .sort()
  73         .map(([_, {bssid, ssid, signal, channel}]) => {
  74             ssid = ssid.padStart(40, ' ');
  75             channel = channel.padEnd(10, ' ');
  76             return `${signal}  ${channel}  ${ssid}  ${bssid}`;
  77         })
  78         .join('\n') + '\n';
  79 }
  80
  81 async function main() {
  82     const interface = await findInterface();
  83
  84     for (;;) {
  85         const scanResult = await scanInterface(interface).catch((err) => err.toString());
  86         process.stdout.write('\033[2J\033[0f');
  87         process.stdout.write(scanResult);
  88         await sleep(3000);
  89     }
  90 }
  91
  92 main().catch((err) => {
  93     console.log('Unhandled error!', err);
  94     process.exit(1);
  95 });