aboutsummaryrefslogtreecommitdiffstats
path: root/src/udp_server.c
blob: 05779138b22050ce9b19d1ccdd9734a116f94157 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
/*
 * Copyright (C) 2003-2011 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 "udp_server.h"
#include "io_thread.h"

#include <glib.h>
#include <unistd.h>
#include <sys/time.h>
#include <errno.h>

#ifdef WIN32
#define WINVER 0x0501
#include <ws2tcpip.h>
#include <winsock.h>
#else
#include <sys/socket.h>
#include <netinet/in.h>
#endif

struct udp_server {
	const struct udp_server_handler *handler;
	void *handler_ctx;

	int fd;
	GIOChannel *channel;
	GSource *source;

	char buffer[8192];
};

static gboolean
udp_in_event(G_GNUC_UNUSED GIOChannel *source,
	     G_GNUC_UNUSED GIOCondition condition,
	     gpointer data)
{
	struct udp_server *udp = data;

	struct sockaddr_storage address_storage;
	struct sockaddr *address = (struct sockaddr *)&address_storage;
	socklen_t address_length = sizeof(address_storage);

	ssize_t nbytes = recvfrom(udp->fd, udp->buffer, sizeof(udp->buffer),
				  MSG_DONTWAIT,
				  address, &address_length);
	if (nbytes <= 0)
		return true;

	udp->handler->datagram(udp->fd, udp->buffer, nbytes,
			       address, address_length, udp->handler_ctx);
	return true;
}

struct udp_server *
udp_server_new(unsigned port,
	       const struct udp_server_handler *handler, void *ctx,
	       GError **error_r)
{
	int fd = socket(PF_INET, SOCK_DGRAM, 0);
	if (fd < 0) {
		g_set_error(error_r, udp_server_quark(), errno,
			    "failed to create UDP socket: %s",
			    g_strerror(errno));
		return NULL;
	}

	const struct sockaddr_in address = {
		.sin_family = AF_INET,
		.sin_addr = {
			.s_addr = htonl(INADDR_ANY),
		},
		.sin_port = htons(port),
	};

	if (bind(fd, (const struct sockaddr *)&address, sizeof(address)) < 0) {
		g_set_error(error_r, udp_server_quark(), errno,
			    "failed to bind UDP port %u: %s",
			    port, g_strerror(errno));
		close(fd);
		return NULL;
	}

	struct udp_server *udp = g_new(struct udp_server, 1);
	udp->handler = handler;
	udp->handler_ctx = ctx;

	udp->fd = fd;
#ifndef G_OS_WIN32
	udp->channel = g_io_channel_unix_new(fd);
#else
	udp->channel = g_io_channel_win32_new_socket(fd);
#endif
	/* NULL encoding means the stream is binary safe */
	g_io_channel_set_encoding(udp->channel, NULL, NULL);
	/* no buffering */
	g_io_channel_set_buffered(udp->channel, false);

	udp->source = g_io_create_watch(udp->channel, G_IO_IN);
	g_source_set_callback(udp->source, (GSourceFunc)udp_in_event, udp,
			      NULL);
	g_source_attach(udp->source, io_thread_context());

	return udp;
}

void
udp_server_free(struct udp_server *udp)
{
	g_source_destroy(udp->source);
	g_source_unref(udp->source);
	g_io_channel_unref(udp->channel);
	close(udp->fd);
	g_free(udp);
}