[project @ 2006-01-08 15:15:17 by rjw]

Automated RISC OS message routing

svn path=/import/netsurf/; revision=2015

riscos/message.c

@@ -0,0 +1,143 @@
+/*
+ * This file is part of NetSurf, http://netsurf.sourceforge.net/
+ * Licensed under the GNU General Public License,
+ *		  http://www.opensource.org/licenses/gpl-license
+ * Copyright 2006 Richard Wilson <info@tinct.net>
+ */
+
+/** \file
+ * Automated RISC OS message routing (implementation).
+ */
+
+#include <assert.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include "oslib/os.h"
+#include "oslib/wimp.h"
+#include "netsurf/riscos/message.h"
+#include "netsurf/utils/log.h"
+#include "netsurf/utils/utils.h"
+
+
+struct active_message {
+	unsigned int message_code;
+	int id;
+	void (*callback)(wimp_event_no event, wimp_message *message);
+	struct active_message *next;
+	struct active_message *previous;
+};
+struct active_message *current_messages = NULL;
+
+
+/**
+ * Sends a message and registers a return route for a bounce.
+ *
+ * \param event		the message event type
+ * \param message	the message to register a route back for
+ * \param task		the task to send a message to, or 0 for broadcast
+ * \param callback	the code to call on a bounce
+ * \return true on success, false otherwise
+ */
+bool ro_message_send_message(wimp_event_no event, wimp_message *message,
+		wimp_t task,
+		void (*callback)(wimp_event_no event, wimp_message *message)) {
+	os_error *error;
+
+	/* send a message */
+	error = xwimp_send_message(event, message, task);
+	if (error) {
+		LOG(("xwimp_send_message: 0x%x: %s",
+				error->errnum, error->errmess));
+		warn_user("WimpError", error->errmess);
+		return false;
+	}
+	
+	/* register the default bounce handler */
+	if (callback) {
+		assert(event == wimp_USER_MESSAGE_RECORDED);
+		return ro_message_register_handler(message, message->action,
+				callback);
+	}
+	return true;
+}
+
+
+
+/**
+ * Registers a return route for a message.
+ *
+ * This function must be called after wimp_send_message so that a
+ * valid value is present in the my_ref field.
+ *
+ * \param message	the message to register a route back for
+ * \param messge_code	the message action code to route
+ * \param callback	the code to call for a matched action
+ * \return true on success, false on memory exhaustion
+ */
+bool ro_message_register_handler(wimp_message *message,
+		unsigned int message_code,
+		void (*callback)(wimp_event_no event, wimp_message *message)) {
+	struct active_message *add;
+
+	assert(message);
+	assert(callback);
+
+	add = (struct active_message *)malloc(sizeof(*add));
+	if (!add)
+		return false;
+	add->message_code = message_code;
+	add->id = message->my_ref;
+	add->callback = callback;
+	add->next = current_messages;
+	add->previous = NULL;
+	current_messages = add;
+	return true;
+}
+
+
+/**
+ * Attempts to route a message.
+ *
+ * \param message	the message to attempt to route
+ * \return true if message was routed, false otherwise
+ */
+bool ro_message_handle_message(wimp_event_no event, wimp_message *message) {
+	struct active_message *test;
+	struct active_message *next;
+	bool handled = true;
+	int ref;
+
+	assert(message);
+
+	/* we can't work without a reference */
+	ref = message->my_ref;
+	if (ref == 0)
+		return false;
+
+	/* handle the message */
+	for (test = current_messages; test; test = test->next) {
+		if ((ref == test->id) &&
+				(message->action == test->message_code)) {
+			handled = true;
+			if (test->callback)
+				test->callback(event, message);
+			break;
+		}
+	}
+
+	/* remove all handlers for this id */
+	next = current_messages;
+	while ((test = next)) {
+	  	next = test->next;
+		if (ref == test->id) {
+			if (test->previous)
+				test->previous->next = test->next;
+			if (test->next)
+				test->next->previous = test->previous;
+			if (current_messages == test)
+				current_messages = test->next;
+		  	free(test);
+		}
+	}
+	return handled;
+}

riscos/message.h

@@ -0,0 +1,26 @@
+/*
+ * This file is part of NetSurf, http://netsurf.sourceforge.net/
+ * Licensed under the GNU General Public License,
+ *                http://www.opensource.org/licenses/gpl-license
+ * Copyright 2006 Richard Wilson <info@tinct.net>
+ */
+
+/** \file
+ * Automated RISC OS message routing (interface).
+ */
+
+
+#ifndef _NETSURF_RISCOS_MESSAGE_H_
+#define _NETSURF_RISCOS_MESSAGE_H_
+
+#include "oslib/wimp.h"
+
+bool ro_message_send_message(wimp_event_no event, wimp_message *message,
+		wimp_t task,
+		void (*callback)(wimp_event_no event, wimp_message *message));
+bool ro_message_register_handler(wimp_message *message,
+		unsigned int message_code,
+		void (*callback)(wimp_event_no event, wimp_message *message));
+bool ro_message_handle_message(wimp_event_no event, wimp_message *message);
+
+#endif