From 4f3ce393f4b5bf1c4d03e8fd1f6931e90fb24396 Mon Sep 17 00:00:00 2001
From: Tony Garnock-Jones <tonygarnockjones@gmail.com>
Date: Mon, 3 Dec 2018 13:03:24 +0000
Subject: [PATCH] Actually parse out TXT data, flawed though it must be

---
 packages/driver-mdns/src/index.js             | 30 ++++++++++++++-----
 .../syntax-playground/src/avahipublish.js     |  6 ++--
 2 files changed, 26 insertions(+), 10 deletions(-)

diff --git a/packages/driver-mdns/src/index.js b/packages/driver-mdns/src/index.js
index 8c95a0a..92f8cfd 100644
--- a/packages/driver-mdns/src/index.js
+++ b/packages/driver-mdns/src/index.js
@@ -126,14 +126,29 @@ spawn named 'driver/avahi-browse' {
       react {
         on retracted S.Readable(stdout) topFacet.stop();
         on message S.Line(stdout, $line) {
-          // We supply a `9` argument to `split` in order to ignore
-          // fields past the port number, because parsing of TXT
-          // record data is unreliable given the way avahi-browse
-          // formats it.
+          // Parsing of TXT record data (appearing after the port
+          // number in an '=' record) is unreliable given the way
+          // avahi-browse formats it.
           //
           // See https://github.com/lathiat/avahi/pull/206.
           //
-          send BrowserInput(id, line.toString('utf-8').split(/;/, 9));
+          // However, it's still useful to have, so we do our best!
+          //
+          const pieces = line.toString('utf-8').split(/;/);
+          if (pieces[0] === '=') {
+            // A resolved address record, which has TXT data.
+            const normalFields = pieces.slice(0, 9);
+            const txtFields = pieces.slice(9).join(';'); // it's these that are dodgy
+            if (txtFields === '') {
+              normalFields.push([]);
+            } else {
+              normalFields.push(txtFields.slice(1,-1).split(/" "/)); // OMG this is vile
+            }
+            send BrowserInput(id, normalFields);
+          } else {
+            // Something else.
+            send BrowserInput(id, pieces);
+          }
         }
 
         on message BrowserInput(id, ["+", $interfaceName, $family, $name, $serviceType, $domain]) {
@@ -143,11 +158,12 @@ spawn named 'driver/avahi-browse' {
               id, ["-", interfaceName, family, name, serviceType, domain]);
             on message BrowserInput(
               id, ['=', interfaceName, family, name, serviceType, domain,
-                   $hostName, $address, $portStr])
+                   $hostName, $address, $portStr, $txtDataRecords])
             {
               const port0 = Number(portStr);
               const port = Number.isNaN(port0) ? null : port0;
-              react assert Discovered(svc, hostName, port, [], address, family, interfaceName);
+              react assert Discovered(
+                svc, hostName, port, txtDataRecords, address, family, interfaceName);
             }
           }
         }
diff --git a/packages/syntax-playground/src/avahipublish.js b/packages/syntax-playground/src/avahipublish.js
index 5de617b..667e298 100644
--- a/packages/syntax-playground/src/avahipublish.js
+++ b/packages/syntax-playground/src/avahipublish.js
@@ -18,10 +18,10 @@ spawn named 'test' {
     on stop  console.log('-', name, hostName, port, txtDataRecords, address, interfaceName);
   }
 
-  during M.Discovered(M.Service($n, $t), $h, $p, _, $a, "IPv4", $i) {
+  during M.Discovered(M.Service($n, $t), $h, $p, $d, $a, "IPv4", $i) {
     if (t !== '_syndicate._tcp') {
-      on start console.log('**', t, n, h, p, a, i);
-      on stop  console.log('==', t, n, h, p, a, i);
+      on start console.log('**', t, n, h, p, d, a, i);
+      on stop  console.log('==', t, n, h, p, d, a, i);
     }
   }
 }