Avoid buffer overrun in kpress() and remove limit on shortcut strings.

st.c

@@ -264,7 +264,7 @@ typedef struct {
 typedef struct {
 	KeySym k;
 	uint mask;
-	char s[ESC_BUF_SIZ];
+	char *s;
 	/* three valued logic variables: 0 indifferent, 1 on, -1 off */
 	signed char appkey;    /* application keypad */
 	signed char appcursor; /* application cursor */
@@ -3585,12 +3585,15 @@ kpress(XEvent *ev) {
 	/* 2. custom keys from config.h */
 	if((customkey = kmap(ksym, e->state))) {
 		len = strlen(customkey);
-		memcpy(buf, customkey, len);
+		ttywrite(customkey, len);
+		if(IS_SET(MODE_ECHO))
+			techo(customkey, len);
+		return;
+	}
+
 	/* 3. composed string from input method */
-	} else {
 	if(len == 0)
 		return;
-
 	if(len == 1 && e->state & Mod1Mask) {
 		if(IS_SET(MODE_8BIT)) {
 			if(*buf < 0177) {
@@ -3603,8 +3606,6 @@ kpress(XEvent *ev) {
 			len = 2;
 		}
 	}
-	}
-
 	ttywrite(buf, len);
 	if(IS_SET(MODE_ECHO))
 		techo(buf, len);