obexd/src/service.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *
 *  OBEX Server
 *
 *  Copyright (C) 2007-2010  Marcel Holtmann <marcel@holtmann.org>
 *
 *
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <stdint.h>
#include <stdlib.h>

#include <glib.h>

#include "obex.h"
#include "service.h"
#include "log.h"

static GSList *drivers = NULL;

const struct obex_service_driver *obex_service_driver_find(GSList *drivers,
			const uint8_t *target, unsigned int target_size,
			const uint8_t *who, unsigned int who_size)
{
	GSList *l;

	for (l = drivers; l; l = l->next) {
		const struct obex_service_driver *driver = l->data;

		/* who is optional, so only check for it if not NULL */
		if (who != NULL && memncmp0(who, who_size, driver->who,
							driver->who_size))
			continue;

		if (memncmp0(target, target_size, driver->target,
						driver->target_size) == 0)
			return driver;
	}

	return NULL;
}

GSList *obex_service_driver_list(uint16_t services)
{
	GSList *l;
	GSList *list = NULL;

	if (services == 0)
		return drivers;

	for (l = drivers; l && services; l = l->next) {
		const struct obex_service_driver *driver = l->data;

		if (driver->service & services) {
			list = g_slist_append(list, (gpointer)driver);
			services &= ~driver->service;
		}
	}

	return list;
}

static const struct obex_service_driver *find_driver(uint16_t service)
{
	GSList *l;

	for (l = drivers; l; l = l->next) {
		const struct obex_service_driver *driver = l->data;

		if (driver->service == service)
			return driver;
	}

	return NULL;
}

int obex_service_driver_register(const struct obex_service_driver *driver)
{
	if (!driver) {
		error("Invalid driver");
		return -EINVAL;
	}

	if (find_driver(driver->service)) {
		error("Permission denied: service %s already registered",
			driver->name);
		return -EPERM;
	}

	DBG("driver %p service %s registered", driver, driver->name);

	/* Drivers that support who has priority */
	if (driver->who)
		drivers = g_slist_prepend(drivers, (gpointer)driver);
	else
		drivers = g_slist_append(drivers, (gpointer)driver);

	return 0;
}

void obex_service_driver_unregister(const struct obex_service_driver *driver)
{
	if (!g_slist_find(drivers, driver)) {
		error("Unable to unregister: No such driver %p", driver);
		return;
	}

	DBG("driver %p service %s unregistered", driver, driver->name);

	drivers = g_slist_remove(drivers, driver);
}