Limit the size of the in-memory tor log (1000 entries by default).

Controlled by hidden pref: extensions.torlauncher.max_tor_log_entries

src/components/tl-protocol.js

@@ -72,6 +72,8 @@ TorProtocolService.prototype =
   kServiceName : "Tor Launcher Protocol Service",
   kClassID: Components.ID("{4F476361-23FB-43EF-A427-B36A14D3208E}"),
 
+  kPrefMaxTorLogEntries: "extensions.torlauncher.max_tor_log_entries",
+
   // nsISupports implementation.
   QueryInterface: function(aIID)
   {
@@ -1173,6 +1175,13 @@ TorProtocolService.prototype =
           let logObj = { date: now, type: eventType, msg: msg };
           if (!this.mTorLog)
             this.mTorLog = [];
+          else
+          {
+            var maxEntries =
+                    TorLauncherUtil.getIntPref(this.kPrefMaxTorLogEntries, 0);
+            if ((maxEntries > 0) && (this.mTorLog.length >= maxEntries))
+              this.mTorLog.splice(0, 1);
+          }
           this.mTorLog.push(logObj);
           break;
         case "STATUS_CLIENT":

src/defaults/preferences/prefs.js

 pref("extensions.torlauncher.loglevel", 4);  // 1=verbose, 2=debug, 3=info, 4=note, 5=warn
 pref("extensions.torlauncher.logmethod", 1);  // 0=stdout, 1=errorconsole, 2=debuglog
+pref("extensions.torlauncher.max_tor_log_entries", 1000);
 
 pref("extensions.torlauncher.control_host", "127.0.0.1");
 pref("extensions.torlauncher.control_port", 9151);