fix: assign one active engine owner

strans.c

@@ -4,6 +4,9 @@
 static Im im;
 static int popup = 0;
 static int visible = 0;
+static Lock ownerlock;
+static uvlong ownerctr;
+static uvlong activeowner;
 static void dictqmap(Im*);
 static void dictqjp(Im*);
 static void backjp(Im*);
@@ -18,6 +21,19 @@ struct Search
 };
 static Search search;
 
+uvlong
+ownernew(void)
+{
+	uvlong n;
+
+	lock(&ownerlock);
+	n = ++ownerctr;
+	if(n == 0)
+		n = ++ownerctr;
+	unlock(&ownerlock);
+	return n;
+}
+
 Lang langs[] = {
 	{LangEN,    nil,       nil,      nil,      nil,     nil,      nil, nil},
 	{LangJP,    "hira",    "kanji",  transmap, backjp,  dictqjp,  nil, nil},
@@ -128,6 +144,9 @@ reset(void)
 {
 	sclear(&im.pre);
 	sclear(&im.raw);
+	search.on = 0;
+	sclear(&search.raw);
+	sclear(&search.text);
 	clearkouho();
 	show();
 }
@@ -715,9 +734,16 @@ init(void)
 	memset(&im, 0, sizeof(im));
 	im.l = getlang(LangEN);
 	memset(&search, 0, sizeof search);
+	activeowner = 0;
 	visible = 0;
 }
 
+static int
+meaningful(Keyreq *kr)
+{
+	return kr->ks != 0 && !ismodkey(kr->ks);
+}
+
 static void
 imhandlekey(Keyreq *kr)
 {
@@ -725,8 +751,30 @@ imhandlekey(Keyreq *kr)
 
 	sclear(&res.commit);
 	sclear(&res.preedit);
-	res.eaten = keystroke(kr->ks, kr->mod, &res.commit);
-	if(kr->want){
+	res.eaten = 1;
+	switch(kr->op){
+	case Keyrelease:
+		if(kr->owner == activeowner){
+			reset();
+			activeowner = 0;
+		}
+		break;
+	case Keyreset:
+		if(kr->owner == activeowner)
+			reset();
+		break;
+	default:
+		res.eaten = 0;
+		if(meaningful(kr)){
+			if(kr->owner != activeowner){
+				reset();
+				activeowner = kr->owner;
+			}
+			res.eaten = keystroke(kr->ks, kr->mod, &res.commit);
+		}
+		break;
+	}
+	if(kr->want && kr->owner == activeowner){
 		if(search.on)
 			res.preedit = search.text;
 		else