/*
 * Copyright (C) 2003-2010 The Music Player Daemon Project
 * http://www.musicpd.org
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include "config.h"
#include "client_internal.h"
#include "fifo_buffer.h"
#include "socket_util.h"
#include "permission.h"

#include <assert.h>
#include <sys/types.h>
#ifdef WIN32
#include <winsock2.h>
#else
#include <sys/socket.h>
#endif
#include <unistd.h>

#ifdef HAVE_LIBWRAP
#include <tcpd.h>
#endif


#define LOG_LEVEL_SECURE G_LOG_LEVEL_INFO

static const char GREETING[] = "OK MPD " PROTOCOL_VERSION "\n";

void client_new(int fd, const struct sockaddr *sa, size_t sa_length, int uid)
{
	static unsigned int next_client_num;
	struct client *client;
	char *remote;

	assert(fd >= 0);

#ifdef HAVE_LIBWRAP
	if (sa->sa_family != AF_UNIX) {
		char *hostaddr = sockaddr_to_string(sa, sa_length, NULL);
		const char *progname = g_get_prgname();

		struct request_info req;
		request_init(&req, RQ_FILE, fd, RQ_DAEMON, progname, 0);

		fromhost(&req);

		if (!hosts_access(&req)) {
			/* tcp wrappers says no */
			g_log(G_LOG_DOMAIN, LOG_LEVEL_SECURE,
			      "libwrap refused connection (libwrap=%s) from %s",
			      progname, hostaddr);

			g_free(hostaddr);
			close(fd);
			return;
		}

		g_free(hostaddr);
	}
#endif	/* HAVE_WRAP */

	if (client_list_is_full()) {
		g_warning("Max Connections Reached!");
		close(fd);
		return;
	}

	client = g_new0(struct client, 1);

#ifndef G_OS_WIN32
	client->channel = g_io_channel_unix_new(fd);
#else
	client->channel = g_io_channel_win32_new_socket(fd);
#endif
	/* GLib is responsible for closing the file descriptor */
	g_io_channel_set_close_on_unref(client->channel, true);
	/* NULL encoding means the stream is binary safe; the MPD
	   protocol is UTF-8 only, but we are doing this call anyway
	   to prevent GLib from messing around with the stream */
	g_io_channel_set_encoding(client->channel, NULL, NULL);
	/* we prefer to do buffering */
	g_io_channel_set_buffered(client->channel, false);

	client->source_id = g_io_add_watch(client->channel,
					   G_IO_IN|G_IO_ERR|G_IO_HUP,
					   client_in_event, client);

	client->input = fifo_buffer_new(4096);

	client->permission = getDefaultPermissions();
	client->uid = uid;

	client->last_activity = g_timer_new();

	client->cmd_list = NULL;
	client->cmd_list_OK = -1;
	client->cmd_list_size = 0;

	client->deferred_send = g_queue_new();
	client->deferred_bytes = 0;
	client->num = next_client_num++;

	client->send_buf_used = 0;

	(void)send(fd, GREETING, sizeof(GREETING) - 1, 0);

	client_list_add(client);

	remote = sockaddr_to_string(sa, sa_length, NULL);
	g_log(G_LOG_DOMAIN, LOG_LEVEL_SECURE,
	      "[%u] opened from %s", client->num, remote);
	g_free(remote);
}

static void
deferred_buffer_free(gpointer data, G_GNUC_UNUSED gpointer user_data)
{
	struct deferred_buffer *buffer = data;
	g_free(buffer);
}

void
client_close(struct client *client)
{
	client_list_remove(client);

	client_set_expired(client);

	g_timer_destroy(client->last_activity);

	if (client->cmd_list) {
		free_cmd_list(client->cmd_list);
		client->cmd_list = NULL;
	}

	g_queue_foreach(client->deferred_send, deferred_buffer_free, NULL);
	g_queue_free(client->deferred_send);

	fifo_buffer_free(client->input);

	g_log(G_LOG_DOMAIN, LOG_LEVEL_SECURE,
	      "[%u] closed", client->num);
	g_free(client);
}
