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1
/*
2
 * UDP prototype streaming system
3
 * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
4
 *
5
 * This file is part of FFmpeg.
6
 *
7
 * FFmpeg is free software; you can redistribute it and/or
8
 * modify it under the terms of the GNU Lesser General Public
9
 * License as published by the Free Software Foundation; either
10
 * version 2.1 of the License, or (at your option) any later version.
11
 *
12
 * FFmpeg is distributed in the hope that it will be useful,
13
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
15
 * Lesser General Public License for more details.
16
 *
17
 * You should have received a copy of the GNU Lesser General Public
18
 * License along with FFmpeg; if not, write to the Free Software
19
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20
 */
21

    
22
/**
23
 * @file
24
 * UDP protocol
25
 */
26

    
27
#define _BSD_SOURCE     /* Needed for using struct ip_mreq with recent glibc */
28

    
29
#include "avformat.h"
30
#include "avio_internal.h"
31
#include "libavutil/parseutils.h"
32
#include "libavutil/fifo.h"
33
#include <unistd.h>
34
#include "internal.h"
35
#include "network.h"
36
#include "os_support.h"
37
#include "url.h"
38
#include <pthread.h>
39
#include <sys/resource.h>
40
#include <sys/time.h>
41

    
42
#ifndef IPV6_ADD_MEMBERSHIP
43
#define IPV6_ADD_MEMBERSHIP IPV6_JOIN_GROUP
44
#define IPV6_DROP_MEMBERSHIP IPV6_LEAVE_GROUP
45
#endif
46

    
47
typedef struct {
48
    int udp_fd;
49
    int ttl;
50
    int buffer_size;
51
    int is_multicast;
52
    int local_port;
53
    int reuse_socket;
54
    struct sockaddr_storage dest_addr;
55
    int dest_addr_len;
56
    int is_connected;
57

    
58
    /* Circular Buffer variables for use in UDP receive code */
59
    int circular_buffer_size;
60
    AVFifoBuffer *fifo;
61
    int circular_buffer_available_max;
62
    int circular_buffer_error;
63
    pthread_t circular_buffer_thread;
64
} UDPContext;
65

    
66
#define UDP_TX_BUF_SIZE 32768
67
#define UDP_MAX_PKT_SIZE 65536
68

    
69
static int udp_set_multicast_ttl(int sockfd, int mcastTTL,
70
                                 struct sockaddr *addr)
71
{
72
#ifdef IP_MULTICAST_TTL
73
    if (addr->sa_family == AF_INET) {
74
        if (setsockopt(sockfd, IPPROTO_IP, IP_MULTICAST_TTL, &mcastTTL, sizeof(mcastTTL)) < 0) {
75
            av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_MULTICAST_TTL): %s\n", strerror(errno));
76
            return -1;
77
        }
78
    }
79
#endif
80
#if defined(IPPROTO_IPV6) && defined(IPV6_MULTICAST_HOPS)
81
    if (addr->sa_family == AF_INET6) {
82
        if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &mcastTTL, sizeof(mcastTTL)) < 0) {
83
            av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_MULTICAST_HOPS): %s\n", strerror(errno));
84
            return -1;
85
        }
86
    }
87
#endif
88
    return 0;
89
}
90

    
91
static int udp_join_multicast_group(int sockfd, struct sockaddr *addr)
92
{
93
#ifdef IP_ADD_MEMBERSHIP
94
    if (addr->sa_family == AF_INET) {
95
        struct ip_mreq mreq;
96

    
97
        mreq.imr_multiaddr.s_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr;
98
        mreq.imr_interface.s_addr= INADDR_ANY;
99
        if (setsockopt(sockfd, IPPROTO_IP, IP_ADD_MEMBERSHIP, (const void *)&mreq, sizeof(mreq)) < 0) {
100
            av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_ADD_MEMBERSHIP): %s\n", strerror(errno));
101
            return -1;
102
        }
103
    }
104
#endif
105
#if HAVE_STRUCT_IPV6_MREQ && defined(IPPROTO_IPV6)
106
    if (addr->sa_family == AF_INET6) {
107
        struct ipv6_mreq mreq6;
108

    
109
        memcpy(&mreq6.ipv6mr_multiaddr, &(((struct sockaddr_in6 *)addr)->sin6_addr), sizeof(struct in6_addr));
110
        mreq6.ipv6mr_interface= 0;
111
        if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_ADD_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) {
112
            av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_ADD_MEMBERSHIP): %s\n", strerror(errno));
113
            return -1;
114
        }
115
    }
116
#endif
117
    return 0;
118
}
119

    
120
static int udp_leave_multicast_group(int sockfd, struct sockaddr *addr)
121
{
122
#ifdef IP_DROP_MEMBERSHIP
123
    if (addr->sa_family == AF_INET) {
124
        struct ip_mreq mreq;
125

    
126
        mreq.imr_multiaddr.s_addr = ((struct sockaddr_in *)addr)->sin_addr.s_addr;
127
        mreq.imr_interface.s_addr= INADDR_ANY;
128
        if (setsockopt(sockfd, IPPROTO_IP, IP_DROP_MEMBERSHIP, (const void *)&mreq, sizeof(mreq)) < 0) {
129
            av_log(NULL, AV_LOG_ERROR, "setsockopt(IP_DROP_MEMBERSHIP): %s\n", strerror(errno));
130
            return -1;
131
        }
132
    }
133
#endif
134
#if HAVE_STRUCT_IPV6_MREQ && defined(IPPROTO_IPV6)
135
    if (addr->sa_family == AF_INET6) {
136
        struct ipv6_mreq mreq6;
137

    
138
        memcpy(&mreq6.ipv6mr_multiaddr, &(((struct sockaddr_in6 *)addr)->sin6_addr), sizeof(struct in6_addr));
139
        mreq6.ipv6mr_interface= 0;
140
        if (setsockopt(sockfd, IPPROTO_IPV6, IPV6_DROP_MEMBERSHIP, &mreq6, sizeof(mreq6)) < 0) {
141
            av_log(NULL, AV_LOG_ERROR, "setsockopt(IPV6_DROP_MEMBERSHIP): %s\n", strerror(errno));
142
            return -1;
143
        }
144
    }
145
#endif
146
    return 0;
147
}
148

    
149
static struct addrinfo* udp_resolve_host(const char *hostname, int port,
150
                                         int type, int family, int flags)
151
{
152
    struct addrinfo hints, *res = 0;
153
    int error;
154
    char sport[16];
155
    const char *node = 0, *service = "0";
156

    
157
    if (port > 0) {
158
        snprintf(sport, sizeof(sport), "%d", port);
159
        service = sport;
160
    }
161
    if ((hostname) && (hostname[0] != '\0') && (hostname[0] != '?')) {
162
        node = hostname;
163
    }
164
    memset(&hints, 0, sizeof(hints));
165
    hints.ai_socktype = type;
166
    hints.ai_family   = family;
167
    hints.ai_flags = flags;
168
    if ((error = getaddrinfo(node, service, &hints, &res))) {
169
        res = NULL;
170
        av_log(NULL, AV_LOG_ERROR, "udp_resolve_host: %s\n", gai_strerror(error));
171
    }
172

    
173
    return res;
174
}
175

    
176
static int udp_set_url(struct sockaddr_storage *addr,
177
                       const char *hostname, int port)
178
{
179
    struct addrinfo *res0;
180
    int addr_len;
181

    
182
    res0 = udp_resolve_host(hostname, port, SOCK_DGRAM, AF_UNSPEC, 0);
183
    if (res0 == 0) return AVERROR(EIO);
184
    memcpy(addr, res0->ai_addr, res0->ai_addrlen);
185
    addr_len = res0->ai_addrlen;
186
    freeaddrinfo(res0);
187

    
188
    return addr_len;
189
}
190

    
191
static int udp_socket_create(UDPContext *s,
192
                             struct sockaddr_storage *addr, int *addr_len)
193
{
194
    int udp_fd = -1;
195
    struct addrinfo *res0 = NULL, *res = NULL;
196
    int family = AF_UNSPEC;
197

    
198
    if (((struct sockaddr *) &s->dest_addr)->sa_family)
199
        family = ((struct sockaddr *) &s->dest_addr)->sa_family;
200
    res0 = udp_resolve_host(0, s->local_port, SOCK_DGRAM, family, AI_PASSIVE);
201
    if (res0 == 0)
202
        goto fail;
203
    for (res = res0; res; res=res->ai_next) {
204
        udp_fd = socket(res->ai_family, SOCK_DGRAM, 0);
205
        if (udp_fd > 0) break;
206
        av_log(NULL, AV_LOG_ERROR, "socket: %s\n", strerror(errno));
207
    }
208

    
209
    if (udp_fd < 0)
210
        goto fail;
211

    
212
    memcpy(addr, res->ai_addr, res->ai_addrlen);
213
    *addr_len = res->ai_addrlen;
214

    
215
    freeaddrinfo(res0);
216

    
217
    return udp_fd;
218

    
219
 fail:
220
    if (udp_fd >= 0)
221
        closesocket(udp_fd);
222
    if(res0)
223
        freeaddrinfo(res0);
224
    return -1;
225
}
226

    
227
static int udp_port(struct sockaddr_storage *addr, int addr_len)
228
{
229
    char sbuf[sizeof(int)*3+1];
230

    
231
    if (getnameinfo((struct sockaddr *)addr, addr_len, NULL, 0,  sbuf, sizeof(sbuf), NI_NUMERICSERV) != 0) {
232
        av_log(NULL, AV_LOG_ERROR, "getnameinfo: %s\n", strerror(errno));
233
        return -1;
234
    }
235

    
236
    return strtol(sbuf, NULL, 10);
237
}
238

    
239

    
240
/**
241
 * If no filename is given to av_open_input_file because you want to
242
 * get the local port first, then you must call this function to set
243
 * the remote server address.
244
 *
245
 * url syntax: udp://host:port[?option=val...]
246
 * option: 'ttl=n'       : set the ttl value (for multicast only)
247
 *         'localport=n' : set the local port
248
 *         'pkt_size=n'  : set max packet size
249
 *         'reuse=1'     : enable reusing the socket
250
 *
251
 * @param h media file context
252
 * @param uri of the remote server
253
 * @return zero if no error.
254
 */
255
int ff_udp_set_remote_url(URLContext *h, const char *uri)
256
{
257
    UDPContext *s = h->priv_data;
258
    char hostname[256], buf[10];
259
    int port;
260
    const char *p;
261

    
262
    av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port, NULL, 0, uri);
263

    
264
    /* set the destination address */
265
    s->dest_addr_len = udp_set_url(&s->dest_addr, hostname, port);
266
    if (s->dest_addr_len < 0) {
267
        return AVERROR(EIO);
268
    }
269
    s->is_multicast = ff_is_multicast_address((struct sockaddr*) &s->dest_addr);
270
    p = strchr(uri, '?');
271
    if (p) {
272
        if (av_find_info_tag(buf, sizeof(buf), "connect", p)) {
273
            int was_connected = s->is_connected;
274
            s->is_connected = strtol(buf, NULL, 10);
275
            if (s->is_connected && !was_connected) {
276
                if (connect(s->udp_fd, (struct sockaddr *) &s->dest_addr,
277
                            s->dest_addr_len)) {
278
                    s->is_connected = 0;
279
                    av_log(h, AV_LOG_ERROR, "connect: %s\n", strerror(errno));
280
                    return AVERROR(EIO);
281
                }
282
            }
283
        }
284
    }
285

    
286
    return 0;
287
}
288

    
289
/**
290
 * Return the local port used by the UDP connection
291
 * @param h media file context
292
 * @return the local port number
293
 */
294
int ff_udp_get_local_port(URLContext *h)
295
{
296
    UDPContext *s = h->priv_data;
297
    return s->local_port;
298
}
299

    
300
/**
301
 * Return the udp file handle for select() usage to wait for several RTP
302
 * streams at the same time.
303
 * @param h media file context
304
 */
305
static int udp_get_file_handle(URLContext *h)
306
{
307
    UDPContext *s = h->priv_data;
308
    return s->udp_fd;
309
}
310

    
311
static void *circular_buffer_task( void *_URLContext)
312
{
313
    URLContext *h = _URLContext;
314
    UDPContext *s = h->priv_data;
315
    fd_set rfds;
316
    struct timeval tv;
317

    
318
    for(;;) {
319
        int left;
320
        int ret;
321
        int len;
322

    
323
        if (url_interrupt_cb()) {
324
            s->circular_buffer_error = EINTR;
325
            return NULL;
326
        }
327

    
328
        FD_ZERO(&rfds);
329
        FD_SET(s->udp_fd, &rfds);
330
        tv.tv_sec = 1;
331
        tv.tv_usec = 0;
332
        ret = select(s->udp_fd + 1, &rfds, NULL, NULL, &tv);
333
        if (ret < 0) {
334
            if (ff_neterrno() == AVERROR(EINTR))
335
                continue;
336
            s->circular_buffer_error = EIO;
337
            return NULL;
338
        }
339

    
340
        if (!(ret > 0 && FD_ISSET(s->udp_fd, &rfds)))
341
            continue;
342

    
343
        /* How much do we have left to the end of the buffer */
344
        /* Whats the minimum we can read so that we dont comletely fill the buffer */
345
        left = av_fifo_space(s->fifo);
346
        left = FFMIN(left, s->fifo->end - s->fifo->wptr);
347

    
348
        /* No Space left, error, what do we do now */
349
        if( !left) {
350
            av_log(h, AV_LOG_ERROR, "circular_buffer: OVERRUN\n");
351
            s->circular_buffer_error = EIO;
352
            return NULL;
353
        }
354

    
355
        len = recv(s->udp_fd, s->fifo->wptr, left, 0);
356
        if (len < 0) {
357
            if (ff_neterrno() != AVERROR(EAGAIN) && ff_neterrno() != AVERROR(EINTR)) {
358
                s->circular_buffer_error = EIO;
359
                return NULL;
360
            }
361
        }
362
        s->fifo->wptr += len;
363
        if (s->fifo->wptr >= s->fifo->end)
364
            s->fifo->wptr = s->fifo->buffer;
365
        s->fifo->wndx += len;
366
    }
367

    
368
    return NULL;
369
}
370

    
371
/* put it in UDP context */
372
/* return non zero if error */
373
static int udp_open(URLContext *h, const char *uri, int flags)
374
{
375
    char hostname[1024];
376
    int port, udp_fd = -1, tmp, bind_ret = -1;
377
    UDPContext *s = NULL;
378
    int is_output;
379
    const char *p;
380
    char buf[256];
381
    struct sockaddr_storage my_addr;
382
    int len;
383
    int reuse_specified = 0;
384

    
385
    h->is_streamed = 1;
386
    h->max_packet_size = 1472;
387

    
388
    is_output = !(flags & AVIO_FLAG_READ);
389

    
390
    s = av_mallocz(sizeof(UDPContext));
391
    if (!s)
392
        return AVERROR(ENOMEM);
393

    
394
    h->priv_data = s;
395
    s->ttl = 16;
396
    s->buffer_size = is_output ? UDP_TX_BUF_SIZE : UDP_MAX_PKT_SIZE;
397

    
398
    s->circular_buffer_size = 7*188*4096;
399

    
400
    p = strchr(uri, '?');
401
    if (p) {
402
        if (av_find_info_tag(buf, sizeof(buf), "reuse", p)) {
403
            char *endptr=NULL;
404
            s->reuse_socket = strtol(buf, &endptr, 10);
405
            /* assume if no digits were found it is a request to enable it */
406
            if (buf == endptr)
407
                s->reuse_socket = 1;
408
            reuse_specified = 1;
409
        }
410
        if (av_find_info_tag(buf, sizeof(buf), "ttl", p)) {
411
            s->ttl = strtol(buf, NULL, 10);
412
        }
413
        if (av_find_info_tag(buf, sizeof(buf), "localport", p)) {
414
            s->local_port = strtol(buf, NULL, 10);
415
        }
416
        if (av_find_info_tag(buf, sizeof(buf), "pkt_size", p)) {
417
            h->max_packet_size = strtol(buf, NULL, 10);
418
        }
419
        if (av_find_info_tag(buf, sizeof(buf), "buffer_size", p)) {
420
            s->buffer_size = strtol(buf, NULL, 10);
421
        }
422
        if (av_find_info_tag(buf, sizeof(buf), "connect", p)) {
423
            s->is_connected = strtol(buf, NULL, 10);
424
        }
425
        if (av_find_info_tag(buf, sizeof(buf), "buf_size", p)) {
426
            s->circular_buffer_size = strtol(buf, NULL, 10)*188;
427
        }
428
    }
429

    
430
    /* fill the dest addr */
431
    av_url_split(NULL, 0, NULL, 0, hostname, sizeof(hostname), &port, NULL, 0, uri);
432

    
433
    /* XXX: fix av_url_split */
434
    if (hostname[0] == '\0' || hostname[0] == '?') {
435
        /* only accepts null hostname if input */
436
        if (!(flags & AVIO_FLAG_READ))
437
            goto fail;
438
    } else {
439
        if (ff_udp_set_remote_url(h, uri) < 0)
440
            goto fail;
441
    }
442

    
443
    if (s->is_multicast && (h->flags & AVIO_FLAG_READ))
444
        s->local_port = port;
445
    udp_fd = udp_socket_create(s, &my_addr, &len);
446
    if (udp_fd < 0)
447
        goto fail;
448

    
449
    /* Follow the requested reuse option, unless it's multicast in which
450
     * case enable reuse unless explicitely disabled.
451
     */
452
    if (s->reuse_socket || (s->is_multicast && !reuse_specified)) {
453
        s->reuse_socket = 1;
454
        if (setsockopt (udp_fd, SOL_SOCKET, SO_REUSEADDR, &(s->reuse_socket), sizeof(s->reuse_socket)) != 0)
455
            goto fail;
456
    }
457

    
458
    /* the bind is needed to give a port to the socket now */
459
    /* if multicast, try the multicast address bind first */
460
    if (s->is_multicast && (h->flags & AVIO_FLAG_READ)) {
461
        bind_ret = bind(udp_fd,(struct sockaddr *)&s->dest_addr, len);
462
    }
463
    /* bind to the local address if not multicast or if the multicast
464
     * bind failed */
465
    if (bind_ret < 0 && bind(udp_fd,(struct sockaddr *)&my_addr, len) < 0)
466
        goto fail;
467

    
468
    len = sizeof(my_addr);
469
    getsockname(udp_fd, (struct sockaddr *)&my_addr, &len);
470
    s->local_port = udp_port(&my_addr, len);
471

    
472
    if (s->is_multicast) {
473
        if (!(h->flags & AVIO_FLAG_READ)) {
474
            /* output */
475
            if (udp_set_multicast_ttl(udp_fd, s->ttl, (struct sockaddr *)&s->dest_addr) < 0)
476
                goto fail;
477
        } else {
478
            /* input */
479
            if (udp_join_multicast_group(udp_fd, (struct sockaddr *)&s->dest_addr) < 0)
480
                goto fail;
481
        }
482
    }
483

    
484
    if (is_output) {
485
        /* limit the tx buf size to limit latency */
486
        tmp = s->buffer_size;
487
        if (setsockopt(udp_fd, SOL_SOCKET, SO_SNDBUF, &tmp, sizeof(tmp)) < 0) {
488
            av_log(h, AV_LOG_ERROR, "setsockopt(SO_SNDBUF): %s\n", strerror(errno));
489
            goto fail;
490
        }
491
    } else {
492
        /* set udp recv buffer size to the largest possible udp packet size to
493
         * avoid losing data on OSes that set this too low by default. */
494
        tmp = s->buffer_size;
495
        if (setsockopt(udp_fd, SOL_SOCKET, SO_RCVBUF, &tmp, sizeof(tmp)) < 0) {
496
            av_log(h, AV_LOG_WARNING, "setsockopt(SO_RECVBUF): %s\n", strerror(errno));
497
        }
498
        /* make the socket non-blocking */
499
        ff_socket_nonblock(udp_fd, 1);
500
    }
501
    if (s->is_connected) {
502
        if (connect(udp_fd, (struct sockaddr *) &s->dest_addr, s->dest_addr_len)) {
503
            av_log(h, AV_LOG_ERROR, "connect: %s\n", strerror(errno));
504
            goto fail;
505
        }
506
    }
507

    
508
    s->udp_fd = udp_fd;
509

    
510
    if (!is_output && s->circular_buffer_size) {
511
        /* start the task going */
512
        s->fifo = av_fifo_alloc(s->circular_buffer_size);
513
        if (pthread_create(&s->circular_buffer_thread, NULL, circular_buffer_task, h)) {
514
            av_log(h, AV_LOG_ERROR, "pthread_create failed\n");
515
            goto fail;
516
        }
517
    }
518

    
519
    return 0;
520
 fail:
521
    if (udp_fd >= 0)
522
        closesocket(udp_fd);
523
        av_fifo_free(s->fifo);
524
    av_free(s);
525
    return AVERROR(EIO);
526
}
527

    
528
static int udp_read(URLContext *h, uint8_t *buf, int size)
529
{
530
    UDPContext *s = h->priv_data;
531
    int ret;
532
    int avail;
533
    int left;
534
    fd_set rfds;
535
    struct timeval tv;
536

    
537
    if (s->circular_buffer_thread) {
538

    
539
        do {
540
            avail = av_fifo_size(s->fifo);
541
            if (avail) { // >=size) {
542

    
543
                // Maximum amount available
544
                size = FFMIN( avail, size);
545
                av_fifo_generic_read(s->fifo, buf, size, NULL);
546
                return size;
547
            }
548
            else {
549
                FD_ZERO(&rfds);
550
                FD_SET(s->udp_fd, &rfds);
551
                tv.tv_sec = 1;
552
                tv.tv_usec = 0;
553
                ret = select(s->udp_fd + 1, &rfds, NULL, NULL, &tv);
554
                if (ret<0)
555
                    return ret;
556
            }
557
        } while( 1);
558
    }
559

    
560
    if (!(h->flags & AVIO_FLAG_NONBLOCK)) {
561
        ret = ff_network_wait_fd(s->udp_fd, 0);
562
        if (ret < 0)
563
            return ret;
564
    }
565
    ret = recv(s->udp_fd, buf, size, 0);
566

    
567
    return ret < 0 ? ff_neterrno() : ret;
568
}
569

    
570
static int udp_write(URLContext *h, const uint8_t *buf, int size)
571
{
572
    UDPContext *s = h->priv_data;
573
    int ret;
574

    
575
    if (!(h->flags & AVIO_FLAG_NONBLOCK)) {
576
        ret = ff_network_wait_fd(s->udp_fd, 1);
577
        if (ret < 0)
578
            return ret;
579
    }
580

    
581
    if (!s->is_connected) {
582
        ret = sendto (s->udp_fd, buf, size, 0,
583
                      (struct sockaddr *) &s->dest_addr,
584
                      s->dest_addr_len);
585
    } else
586
        ret = send(s->udp_fd, buf, size, 0);
587

    
588
    return ret < 0 ? ff_neterrno() : ret;
589
}
590

    
591
static int udp_close(URLContext *h)
592
{
593
    UDPContext *s = h->priv_data;
594

    
595
    if (s->is_multicast && (h->flags & AVIO_FLAG_READ))
596
        udp_leave_multicast_group(s->udp_fd, (struct sockaddr *)&s->dest_addr);
597
    closesocket(s->udp_fd);
598
    av_log( h, AV_LOG_INFO, "circular_buffer_info max:%d%%\r\n", (s->circular_buffer_available_max*100)/s->circular_buffer_size);
599
    av_fifo_free(s->fifo);
600
    av_free(s);
601
    return 0;
602
}
603

    
604
URLProtocol ff_udp_protocol = {
605
    .name                = "udp",
606
    .url_open            = udp_open,
607
    .url_read            = udp_read,
608
    .url_write           = udp_write,
609
    .url_close           = udp_close,
610
    .url_get_file_handle = udp_get_file_handle,
611
};