raspbian wifi support, updated docs

lib/wifi.js

@@ -15,6 +15,7 @@
 
 const os = require('os');
 const exec = require('child_process').exec;
+const execSync = require('child_process').execSync;
 const util = require('./util');
 
 let _platform = process.platform;
@@ -144,10 +145,101 @@ function wifiNetworks(callback) {
             });
           });
 
-          if (callback) {
-            callback(result);
+          if (result.length === 0) {
+            try {
+              const iwconfigParts = execSync('export LC_ALL=C; iwconfig 2>/dev/null; unset LC_ALL').toString().split('\n\n');
+              let iface = '';
+              for (let i = 0; i < iwconfigParts.length; i++) {
+                if (iwconfigParts[i].indexOf('no wireless') === -1) {
+                  iface = iwconfigParts[i].split(' ')[0];
+                }
+              }
+              if (iface()) {
+                let iwlistParts = execSync(`export LC_ALL=C; iwlist ${iface} sscan 2>/dev/null; unset LC_ALL`).toString().split('        Cell ');
+                if (iwlistParts.length > 1) {
+                  iwlistParts.shift();
+                  for (let i = 0; i < iwlistParts.length; i++) {
+                    const lines = iwlistParts[i].split('\n');
+                    const channel = util.getValue(lines, 'channel', ':', true);
+                    const address = util.getValue(lines, 'address', ':', true);
+                    const mode = util.getValue(lines, 'mode', ':', true);
+                    const frequency = util.getValue(lines, 'frequency', ':', true);
+                    const qualityString = util.getValue(lines, 'Quality', '=', true);
+                    const dbParts = qualityString.toLowerCase().split('signal level=');
+                    const db = dbParts.length > 1 ? util.toInt(dbParts[1]) : 0;
+                    const quality = db ? wifiQualityFromDB(db) : 0;
+                    const ssid = util.getValue(lines, 'essid', ':', true);
+
+                    // security and wpa-flags
+                    const isWpa = iwlistParts[i].indexOf(' WPA ') >= 0;
+                    const isWpa2 = iwlistParts[i].indexOf('WPA2 ') >= 0;
+                    const security = [];
+                    if (isWpa) { security.push('WPA'); }
+                    if (isWpa2) { security.push('WPA2'); }
+                    const wpaFlags = [];
+                    let wpaFlag = '';
+                    lines.forEach(function (line) {
+                      const l = line.trim().toLowerCase();
+                      if (l.indexOf('group cipher')) {
+                        if (wpaFlag) {
+                          wpaFlags.push(wpaFlag);
+                        }
+                        const parts = l.split(':');
+                        if (parts.length > 1) {
+                          wpaFlag = parts[1].trim();
+                        }
+                      }
+                      if (l.indexOf('pairwise cipher')) {
+                        const parts = l.split(':');
+                        if (parts.length > 1) {
+                          if (parts[i].indexOf('tkip')) { wpaFlag = wpaFlag ? 'TKIP/' + wpaFlag : 'TKIP'; }
+                          else if (parts[i].indexOf('ccmp')) { wpaFlag = wpaFlag ? 'CCMP/' + wpaFlag : 'CCMP'; }
+                          else if (parts[i].indexOf('proprietary')) { wpaFlag = wpaFlag ? 'PROP/' + wpaFlag : 'PROP'; }
+                        }
+                      }
+                      if (l.indexOf('Authentication Suites')) {
+                        const parts = l.split(':');
+                        if (parts.length > 1) {
+                          if (parts[i].indexOf('802.1x')) { wpaFlag = wpaFlag ? '802.1x/' + wpaFlag : '802.1x'; }
+                          else if (parts[i].indexOf('psk')) { wpaFlag = wpaFlag ? 'PSK/' + wpaFlag : 'PSK'; }
+                        }
+                      }
+                    });
+                    if (wpaFlag) {
+                      wpaFlags.push(wpaFlag);
+                    }
+
+                    result.push({
+                      ssid,
+                      bssid: address,
+                      mode,
+                      channel: channel ? util.toInt(channel) : null,
+                      frequency: frequency ? util.toInt(frequency.replace('.', '')) : null,
+                      signalLevel: db,
+                      quality,
+                      security,
+                      wpaFlags,
+                      rsnFlags: []
+                    });
+                  }
+                }
+              }
+              if (callback) {
+                callback(result);
+              }
+              resolve(result);
+            } catch (e) {
+              if (callback) {
+                callback(result);
+              }
+              resolve(result);
+            }
+          } else {
+            if (callback) {
+              callback(result);
+            }
+            resolve(result);
           }
-          resolve(result);
         });
       } else if (_darwin) {
         let cmd = '/System/Library/PrivateFrameworks/Apple80211.framework/Versions/Current/Resources/airport -s';