core/desktopentry: handle string escape sequences

Author: bbedward

src/core/desktopentry.cpp

@@ -270,15 +270,22 @@ QVector<QString> DesktopEntry::parseExecString(const QString& execString) {
 					escape = 0;
 				}
 			} else if (escape != 0) {
-				if (escape != 2) {
-					// Technically this is an illegal state, but the spec has a terrible double escape
-					// rule in strings for no discernable reason. Assuming someone might understandably
-					// misunderstand it, treat it as a normal escape and log it.
-					qCWarning(logDesktopEntry).noquote()
-					    << "Illegal escape sequence in desktop entry exec string:" << execString;
+				if (escape == 2) {
+					currentArgument += c;
+				} else {
+					switch (c.unicode()) {
+					case 's': currentArgument += u' '; break;
+					case 'n': currentArgument += u'\n'; break;
+					case 't': currentArgument += u'\t'; break;
+					case 'r': currentArgument += u'\r'; break;
+					case '\\': currentArgument += u'\\'; break;
+					default:
+						qCWarning(logDesktopEntry).noquote()
+						    << "Illegal escape sequence in desktop entry exec string:" << execString;
+						currentArgument += c;
+						break;
+					}
 				}
-
-				currentArgument += c;
 				escape = 0;
 			} else if (c == u'"' || c == u'\'') {
 				parsingString = false;