mouse shortcuts: allow same functions as kb shortcuts

Previously mouse shortcuts supported only ttywrite.

This required adding an "Arg" function ttysend - which does what the
original mouse shortcuts did.

config.def.h

@@ -155,9 +155,9 @@ static unsigned int defaultattr = 11;
  * Beware that overloading Button1 will disable the selection.
  */
 static MouseShortcut mshortcuts[] = {
-	/* button               mask            string */
-	{ Button4,              XK_ANY_MOD,     "\031" },
-	{ Button5,              XK_ANY_MOD,     "\005" },
+	/* mask                 button   function        argument */
+	{ XK_ANY_MOD,           Button4, ttysend,        {.s = "\031"} },
+	{ XK_ANY_MOD,           Button5, ttysend,        {.s = "\005"} },
 };
 
 /* Internal keyboard shortcuts. */

st.h

@@ -74,6 +74,7 @@ typedef union {
 	uint ui;
 	float f;
 	const void *v;
+	const char *s;
 } Arg;
 
 void die(const char *, ...);

x.c

@@ -29,9 +29,10 @@ typedef struct {
 } Shortcut;
 
 typedef struct {
-	uint b;
-	uint mask;
-	char *s;
+	uint mod;
+	uint button;
+	void (*func)(const Arg *);
+	const Arg arg;
 } MouseShortcut;
 
 typedef struct {
@@ -56,6 +57,7 @@ static void selpaste(const Arg *);
 static void zoom(const Arg *);
 static void zoomabs(const Arg *);
 static void zoomreset(const Arg *);
+static void ttysend(const Arg *);
 
 /* config.h for applying patches and the configuration. */
 #include "config.h"
@@ -312,6 +314,12 @@ zoomreset(const Arg *arg)
 	}
 }
 
+void
+ttysend(const Arg *arg)
+{
+	ttywrite(arg->s, strlen(arg->s), 1);
+}
+
 int
 evcol(XEvent *e)
 {
@@ -421,9 +429,9 @@ bpress(XEvent *e)
 	}
 
 	for (ms = mshortcuts; ms < mshortcuts + LEN(mshortcuts); ms++) {
-		if (e->xbutton.button == ms->b
-				&& match(ms->mask, e->xbutton.state)) {
-			ttywrite(ms->s, strlen(ms->s), 1);
+		if (e->xbutton.button == ms->button
+				&& match(ms->mod, e->xbutton.state)) {
+			ms->func(&(ms->arg));
 			return;
 		}
 	}