From a8115a900015abf538e3105e2520196bf67aded2 Mon Sep 17 00:00:00 2001
From: Bill Somerville <bill@classdesign.com>
Date: Thu, 4 Jun 2020 03:41:11 +0100
Subject: [PATCH] Escape regexp meta-characters in search strings

This resolves the regression where Highlight Callsign UDP messages
fail when the callsign contains a '+' character.
---
 widgets/displaytext.cpp | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/widgets/displaytext.cpp b/widgets/displaytext.cpp
index ae865bc9d..ef91761fc 100644
--- a/widgets/displaytext.cpp
+++ b/widgets/displaytext.cpp
@@ -553,7 +553,14 @@ void DisplayText::highlight_callsign (QString const& callsign, QColor const& bg,
     {
       return;
     }
-  QRegularExpression target {QString {"<?"} + callsign + QString {">?"}, QRegularExpression::DontCaptureOption};
+  auto regexp = callsign;
+  // allow for hashed callsigns and escape any regexp metacharacters
+  QRegularExpression target {QString {"<?"}
+                             + regexp.replace (QLatin1Char {'+'}, QLatin1String {"\\+"})
+                                 .replace (QLatin1Char {'.'}, QLatin1String {"\\."})
+                                 .replace (QLatin1Char {'?'}, QLatin1String {"\\?"})
+                             + QString {">?"}
+                             , QRegularExpression::DontCaptureOption};
   QTextCharFormat old_format {currentCharFormat ()};
   QTextCursor cursor {document ()};
   if (last_period_only)