(shmif/tui) move push_message to shmif from tui

The need for this re-appears practically every time someone wants
to add a short message to the clipboard, so better to make it part
of the interop support functions.

src/shmif/arcan_shmif_control.c

@@ -3747,6 +3747,51 @@ shmif_reset_hook arcan_shmif_resetfunc(
 	return old_hook;
 }
 
+#include "../frameserver/util/utf8.c"
+bool arcan_shmif_pushutf8(
+	struct arcan_shmif_cont* acon, struct arcan_event* base,
+	const char* msg, size_t len)
+{
+	uint32_t state = 0, codepoint = 0;
+	const char* outs = msg;
+	size_t maxlen = sizeof(base->ext.message.data) - 1;
+
+/* utf8- point aligned against block size */
+	while (len > maxlen){
+		size_t i, lastok = 0;
+		state = 0;
+		for (i = 0; i <= maxlen - 1; i++){
+			if (UTF8_ACCEPT == utf8_decode(&state, &codepoint, (uint8_t)(msg[i])))
+				lastok = i;
+
+			if (i != lastok){
+				if (0 == i)
+					return false;
+			}
+		}
+
+		memcpy(base->ext.message.data, outs, lastok);
+		base->ext.message.data[lastok] = '\0';
+		len -= lastok;
+		outs += lastok;
+		if (len)
+			base->ext.message.multipart = 1;
+		else
+			base->ext.message.multipart = 0;
+
+		arcan_shmif_enqueue(acon, base);
+	}
+
+/* flush remaining */
+	if (len){
+		snprintf((char*)base->ext.message.data, maxlen, "%s", outs);
+		base->ext.message.multipart = 0;
+		arcan_shmif_enqueue(acon, base);
+	}
+
+	return true;
+}
+
 /*
  * Missing: special behavior for SHMIF_RHINT_SUBREGION_CHAIN, setup chain of
  * atomic [uint32_t, bitfl] and walk from first position to last free. Bitfl

src/shmif/arcan_shmif_interop.h

@@ -524,6 +524,20 @@ bool arcan_shmif_mousestate_ioev(
 	struct arcan_shmif_cont*, uint8_t* state,
 	struct arcan_ioevent* inev, int* out_x, int* out_y);
 
+/*
+ * Support function for taking a small utf-8 encoded text string on top
+ * of [baseev] (will be modified).
+ *
+ * It will validate and terminate / return false if [msg] fails proper utf-8
+ * validation.
+ *
+ * This is mainly useful for _MESSAGE events on clipboard subsegments for
+ * shorter (comparable to non-incr text/utf-8 in X11).
+ */
+bool arcan_shmif_pushutf8(
+	struct arcan_shmif_cont*, struct arcan_event* baseev,
+	const char* msg, size_t msg_sz);
+
 /*
  * Part of auxiliary library, pulls in more dependencies and boiler-plate
  * for setting up accelerated graphics

src/shmif/tui/core/clipboard.c

@@ -37,49 +37,6 @@ void tui_clipboard_check(struct tui_context* tui)
 		arcan_shmif_drop(&tui->clip_in);
 }
 
-bool tui_push_message(struct arcan_shmif_cont* acon,
-	struct arcan_event* base, const char* msg, size_t len)
-{
-	uint32_t state = 0, codepoint = 0;
-	const char* outs = msg;
-	size_t maxlen = sizeof(base->ext.message.data) - 1;
-
-/* utf8- point aligned against block size */
-	while (len > maxlen){
-		size_t i, lastok = 0;
-		state = 0;
-		for (i = 0; i <= maxlen - 1; i++){
-			if (UTF8_ACCEPT == utf8_decode(&state, &codepoint, (uint8_t)(msg[i])))
-				lastok = i;
-
-			if (i != lastok){
-				if (0 == i)
-					return false;
-			}
-		}
-
-		memcpy(base->ext.message.data, outs, lastok);
-		base->ext.message.data[lastok] = '\0';
-		len -= lastok;
-		outs += lastok;
-		if (len)
-			base->ext.message.multipart = 1;
-		else
-			base->ext.message.multipart = 0;
-
-		arcan_shmif_enqueue(acon, base);
-	}
-
-/* flush remaining */
-	if (len){
-		snprintf((char*)base->ext.message.data, maxlen, "%s", outs);
-		base->ext.message.multipart = 0;
-		arcan_shmif_enqueue(acon, base);
-	}
-
-	return true;
-}
-
 bool tui_clipboard_push(struct tui_context* tui, const char* sel, size_t len)
 {
 /*
@@ -95,5 +52,5 @@ bool tui_clipboard_push(struct tui_context* tui, const char* sel, size_t len)
 		.ext.kind = ARCAN_EVENT(MESSAGE)
 	};
 
-	return tui_push_message(&tui->clip_out, &msgev, sel, len);
+	return arcan_shmif_pushutf8(&tui->clip_out, &msgev, sel, len);
 }

src/shmif/tui/tui.c

@@ -1075,14 +1075,14 @@ void arcan_tui_message(
 		workstr[0] = '>';
 		memcpy(&workstr[1], msg, len);
 		workstr[len+1] = '\0';
-		tui_push_message(&c->acon, &outev, msg, len);
+		arcan_shmif_pushutf8(&c->acon, &outev, msg, len);
 		free(workstr);
 		return;
 	}
 	else
 		return;
 
-	tui_push_message(&c->acon, &outev, msg, len);
+	arcan_shmif_pushutf8(&c->acon, &outev, msg, len);
 }
 
 pid_t arcan_tui_handover(

src/shmif/tui/tui_int.h

@@ -218,9 +218,6 @@ int tui_tpack_unpack(struct tui_context* tui,
 /*                  DISPATCH  (tui_dispatch.c) related code                   */
 /* ========================================================================== */
 
-bool tui_push_message(struct arcan_shmif_cont* tui,
-	struct arcan_event* base, const char* msg, size_t len);
-
 /*
  * Poll the incoming event queue on the tui segment, process TARGET events
  * and forward IO events to