libavformat/avio.c

   1 /*
   2  * unbuffered I/O
   3  * Copyright (c) 2001 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 #include "libavutil/avstring.h"
  23 #include "libavutil/dict.h"
  24 #include "libavutil/mem.h"
  25 #include "libavutil/opt.h"
  26 #include "libavutil/time.h"
  27 #include "libavutil/avassert.h"
  28 #include "avio_internal.h"
  29 #include "os_support.h"
  30 #include "internal.h"
  31 #if CONFIG_NETWORK
  32 #include "network.h"
  33 #endif
  34 #include "url.h"
  35
  36 #define IO_BUFFER_SIZE 32768
  37
  38 /** @name Logging context. */
  39 /*@{*/
  40 static const char *urlcontext_to_name(void *ptr)
  41 {
  42     URLContext *h = (URLContext *)ptr;
  43     if (h->prot)
  44         return h->prot->name;
  45     else
  46         return "NULL";
  47 }
  48
  49 static void *urlcontext_child_next(void *obj, void *prev)
  50 {
  51     URLContext *h = obj;
  52     if (!prev && h->priv_data && h->prot->priv_data_class)
  53         return h->priv_data;
  54     return NULL;
  55 }
  56
  57 #define OFFSET(x) offsetof(URLContext,x)
  58 #define E AV_OPT_FLAG_ENCODING_PARAM
  59 #define D AV_OPT_FLAG_DECODING_PARAM
  60 static const AVOption options[] = {
  61     {"protocol_whitelist", "List of protocols that are allowed to be used", OFFSET(protocol_whitelist), AV_OPT_TYPE_STRING, { .str = NULL },  0, 0, D },
  62     {"protocol_blacklist", "List of protocols that are not allowed to be used", OFFSET(protocol_blacklist), AV_OPT_TYPE_STRING, { .str = NULL },  0, 0, D },
  63     {"rw_timeout", "Timeout for IO operations (in microseconds)", offsetof(URLContext, rw_timeout), AV_OPT_TYPE_INT64, { .i64 = 0 }, 0, INT64_MAX, AV_OPT_FLAG_ENCODING_PARAM | AV_OPT_FLAG_DECODING_PARAM },
  64     { NULL }
  65 };
  66
  67 static const AVClass url_context_class = {
  68     .class_name       = "URLContext",
  69     .item_name        = urlcontext_to_name,
  70     .option           = options,
  71     .version          = LIBAVUTIL_VERSION_INT,
  72     .child_next       = urlcontext_child_next,
  73     .child_class_iterate = ff_urlcontext_child_class_iterate,
  74 };
  75 /*@}*/
  76
  77 static void *avio_child_next(void *obj, void *prev)
  78 {
  79     AVIOContext *s = obj;
  80     return prev ? NULL : s->opaque;
  81 }
  82
  83 static const AVClass *child_class_iterate(void **iter)
  84 {
  85     const AVClass *c = *iter ? NULL : &url_context_class;
  86     *iter = (void*)(uintptr_t)c;
  87     return c;
  88 }
  89
  90 #define AVIOOFFSET(x) offsetof(AVIOContext,x)
  91 #define E AV_OPT_FLAG_ENCODING_PARAM
  92 #define D AV_OPT_FLAG_DECODING_PARAM
  93 static const AVOption avio_options[] = {
  94     {"protocol_whitelist", "List of protocols that are allowed to be used", AVIOOFFSET(protocol_whitelist), AV_OPT_TYPE_STRING, { .str = NULL },  0, 0, D },
  95     { NULL },
  96 };
  97
  98 const AVClass ff_avio_class = {
  99     .class_name = "AVIOContext",
 100     .item_name  = av_default_item_name,
 101     .version    = LIBAVUTIL_VERSION_INT,
 102     .option     = avio_options,
 103     .child_next = avio_child_next,
 104     .child_class_iterate = child_class_iterate,
 105 };
 106
 107 URLContext *ffio_geturlcontext(AVIOContext *s)
 108 {
 109     if (!s)
 110         return NULL;
 111
 112     if (s->opaque && s->read_packet == ffurl_read2)
 113         return s->opaque;
 114     else
 115         return NULL;
 116 }
 117
 118 static int url_alloc_for_protocol(URLContext **puc, const URLProtocol *up,
 119                                   const char *filename, int flags,
 120                                   const AVIOInterruptCB *int_cb)
 121 {
 122     URLContext *uc;
 123     int err;
 124
 125 #if CONFIG_NETWORK
 126     if (up->flags & URL_PROTOCOL_FLAG_NETWORK && !ff_network_init())
 127         return AVERROR(EIO);
 128 #endif
 129     if ((flags & AVIO_FLAG_READ) && !up->url_read) {
 130         av_log(NULL, AV_LOG_ERROR,
 131                "Impossible to open the '%s' protocol for reading\n", up->name);
 132         return AVERROR(EIO);
 133     }
 134     if ((flags & AVIO_FLAG_WRITE) && !up->url_write) {
 135         av_log(NULL, AV_LOG_ERROR,
 136                "Impossible to open the '%s' protocol for writing\n", up->name);
 137         return AVERROR(EIO);
 138     }
 139     uc = av_mallocz(sizeof(URLContext) + strlen(filename) + 1);
 140     if (!uc) {
 141         err = AVERROR(ENOMEM);
 142         goto fail;
 143     }
 144     uc->av_class = &url_context_class;
 145     uc->filename = (char *)&uc[1];
 146     strcpy(uc->filename, filename);
 147     uc->prot            = up;
 148     uc->flags           = flags;
 149     uc->is_streamed     = 0; /* default = not streamed */
 150     uc->max_packet_size = 0; /* default: stream file */
 151     if (up->priv_data_size) {
 152         uc->priv_data = av_mallocz(up->priv_data_size);
 153         if (!uc->priv_data) {
 154             err = AVERROR(ENOMEM);
 155             goto fail;
 156         }
 157         if (up->priv_data_class) {
 158             char *start;
 159             *(const AVClass **)uc->priv_data = up->priv_data_class;
 160             av_opt_set_defaults(uc->priv_data);
 161             if (av_strstart(uc->filename, up->name, (const char**)&start) && *start == ',') {
 162                 int ret= 0;
 163                 char *p= start;
 164                 char sep= *++p;
 165                 char *key, *val;
 166                 p++;
 167
 168                 if (strcmp(up->name, "subfile"))
 169                     ret = AVERROR(EINVAL);
 170
 171                 while(ret >= 0 && (key= strchr(p, sep)) && p<key && (val = strchr(key+1, sep))){
 172                     *val= *key= 0;
 173                     ret = av_opt_set(uc->priv_data, p, key+1, 0);
 174                     if (ret == AVERROR_OPTION_NOT_FOUND)
 175                         av_log(uc, AV_LOG_ERROR, "Key '%s' not found.\n", p);
 176                     *val= *key= sep;
 177                     p= val+1;
 178                 }
 179                 if(ret<0 || p!=key){
 180                     av_log(uc, AV_LOG_ERROR, "Error parsing options string %s\n", start);
 181                     err = AVERROR(EINVAL);
 182                     goto fail;
 183                 }
 184                 memmove(start, key+1, strlen(key));
 185             }
 186         }
 187     }
 188     if (int_cb)
 189         uc->interrupt_callback = *int_cb;
 190
 191     *puc = uc;
 192     return 0;
 193 fail:
 194     *puc = NULL;
 195     if (uc)
 196         av_freep(&uc->priv_data);
 197     av_freep(&uc);
 198 #if CONFIG_NETWORK
 199     if (up->flags & URL_PROTOCOL_FLAG_NETWORK)
 200         ff_network_close();
 201 #endif
 202     return err;
 203 }
 204
 205 int ffurl_connect(URLContext *uc, AVDictionary **options)
 206 {
 207     int err;
 208     AVDictionary *tmp_opts = NULL;
 209     AVDictionaryEntry *e;
 210
 211     if (!options)
 212         options = &tmp_opts;
 213
 214     // Check that URLContext was initialized correctly and lists are matching if set
 215     av_assert0(!(e=av_dict_get(*options, "protocol_whitelist", NULL, 0)) ||
 216                (uc->protocol_whitelist && !strcmp(uc->protocol_whitelist, e->value)));
 217     av_assert0(!(e=av_dict_get(*options, "protocol_blacklist", NULL, 0)) ||
 218                (uc->protocol_blacklist && !strcmp(uc->protocol_blacklist, e->value)));
 219
 220     if (uc->protocol_whitelist && av_match_list(uc->prot->name, uc->protocol_whitelist, ',') <= 0) {
 221         av_log(uc, AV_LOG_ERROR, "Protocol '%s' not on whitelist '%s'!\n", uc->prot->name, uc->protocol_whitelist);
 222         return AVERROR(EINVAL);
 223     }
 224
 225     if (uc->protocol_blacklist && av_match_list(uc->prot->name, uc->protocol_blacklist, ',') > 0) {
 226         av_log(uc, AV_LOG_ERROR, "Protocol '%s' on blacklist '%s'!\n", uc->prot->name, uc->protocol_blacklist);
 227         return AVERROR(EINVAL);
 228     }
 229
 230     if (!uc->protocol_whitelist && uc->prot->default_whitelist) {
 231         av_log(uc, AV_LOG_DEBUG, "Setting default whitelist '%s'\n", uc->prot->default_whitelist);
 232         uc->protocol_whitelist = av_strdup(uc->prot->default_whitelist);
 233         if (!uc->protocol_whitelist) {
 234             return AVERROR(ENOMEM);
 235         }
 236     } else if (!uc->protocol_whitelist)
 237         av_log(uc, AV_LOG_DEBUG, "No default whitelist set\n"); // This should be an error once all declare a default whitelist
 238
 239     if ((err = av_dict_set(options, "protocol_whitelist", uc->protocol_whitelist, 0)) < 0)
 240         return err;
 241     if ((err = av_dict_set(options, "protocol_blacklist", uc->protocol_blacklist, 0)) < 0)
 242         return err;
 243
 244     err =
 245         uc->prot->url_open2 ? uc->prot->url_open2(uc,
 246                                                   uc->filename,
 247                                                   uc->flags,
 248                                                   options) :
 249         uc->prot->url_open(uc, uc->filename, uc->flags);
 250
 251     av_dict_set(options, "protocol_whitelist", NULL, 0);
 252     av_dict_set(options, "protocol_blacklist", NULL, 0);
 253
 254     if (err)
 255         return err;
 256     uc->is_connected = 1;
 257     /* We must be careful here as ffurl_seek() could be slow,
 258      * for example for http */
 259     if ((uc->flags & AVIO_FLAG_WRITE) || !strcmp(uc->prot->name, "file"))
 260         if (!uc->is_streamed && ffurl_seek(uc, 0, SEEK_SET) < 0)
 261             uc->is_streamed = 1;
 262     return 0;
 263 }
 264
 265 int ffurl_accept(URLContext *s, URLContext **c)
 266 {
 267     av_assert0(!*c);
 268     if (s->prot->url_accept)
 269         return s->prot->url_accept(s, c);
 270     return AVERROR(EBADF);
 271 }
 272
 273 int avio_accept(AVIOContext *s, AVIOContext **c)
 274 {
 275     int ret;
 276     URLContext *sc = s->opaque;
 277     URLContext *cc = NULL;
 278     ret = ffurl_accept(sc, &cc);
 279     if (ret < 0)
 280         return ret;
 281     return ffio_fdopen(c, cc);
 282 }
 283
 284 int ffurl_handshake(URLContext *c)
 285 {
 286     int ret;
 287     if (c->prot->url_handshake) {
 288         ret = c->prot->url_handshake(c);
 289         if (ret)
 290             return ret;
 291     }
 292     c->is_connected = 1;
 293     return 0;
 294 }
 295
 296 int avio_handshake(AVIOContext *c)
 297 {
 298     URLContext *cc = c->opaque;
 299     return ffurl_handshake(cc);
 300 }
 301
 302 #define URL_SCHEME_CHARS                        \
 303     "abcdefghijklmnopqrstuvwxyz"                \
 304     "ABCDEFGHIJKLMNOPQRSTUVWXYZ"                \
 305     "0123456789+-."
 306
 307 static const struct URLProtocol *url_find_protocol(const char *filename)
 308 {
 309     const URLProtocol **protocols;
 310     char proto_str[128], proto_nested[128], *ptr;
 311     size_t proto_len = strspn(filename, URL_SCHEME_CHARS);
 312     int i;
 313
 314     if (filename[proto_len] != ':' &&
 315         (strncmp(filename, "subfile,", 8) || !strchr(filename + proto_len + 1, ':')) ||
 316         is_dos_path(filename))
 317         strcpy(proto_str, "file");
 318     else
 319         av_strlcpy(proto_str, filename,
 320                    FFMIN(proto_len + 1, sizeof(proto_str)));
 321
 322     av_strlcpy(proto_nested, proto_str, sizeof(proto_nested));
 323     if ((ptr = strchr(proto_nested, '+')))
 324         *ptr = '\0';
 325
 326     protocols = ffurl_get_protocols(NULL, NULL);
 327     if (!protocols)
 328         return NULL;
 329     for (i = 0; protocols[i]; i++) {
 330             const URLProtocol *up = protocols[i];
 331         if (!strcmp(proto_str, up->name)) {
 332             av_freep(&protocols);
 333             return up;
 334         }
 335         if (up->flags & URL_PROTOCOL_FLAG_NESTED_SCHEME &&
 336             !strcmp(proto_nested, up->name)) {
 337             av_freep(&protocols);
 338             return up;
 339         }
 340     }
 341     av_freep(&protocols);
 342     if (av_strstart(filename, "https:", NULL) || av_strstart(filename, "tls:", NULL) ||
 343         av_strstart(filename, "dtls:", NULL))
 344         av_log(NULL, AV_LOG_WARNING, "https or dtls protocol not found, recompile FFmpeg with "
 345                                      "openssl, gnutls or securetransport enabled.\n");
 346
 347     return NULL;
 348 }
 349
 350 int ffurl_alloc(URLContext **puc, const char *filename, int flags,
 351                 const AVIOInterruptCB *int_cb)
 352 {
 353     const URLProtocol *p = NULL;
 354
 355     p = url_find_protocol(filename);
 356     if (p)
 357        return url_alloc_for_protocol(puc, p, filename, flags, int_cb);
 358
 359     *puc = NULL;
 360     return AVERROR_PROTOCOL_NOT_FOUND;
 361 }
 362
 363 int ffurl_open_whitelist(URLContext **puc, const char *filename, int flags,
 364                          const AVIOInterruptCB *int_cb, AVDictionary **options,
 365                          const char *whitelist, const char* blacklist,
 366                          URLContext *parent)
 367 {
 368     AVDictionary *tmp_opts = NULL;
 369     AVDictionaryEntry *e;
 370     int ret = ffurl_alloc(puc, filename, flags, int_cb);
 371     if (ret < 0)
 372         return ret;
 373     if (parent) {
 374         ret = av_opt_copy(*puc, parent);
 375         if (ret < 0)
 376             goto fail;
 377     }
 378     if (options &&
 379         (ret = av_opt_set_dict(*puc, options)) < 0)
 380         goto fail;
 381     if (options && (*puc)->prot->priv_data_class &&
 382         (ret = av_opt_set_dict((*puc)->priv_data, options)) < 0)
 383         goto fail;
 384
 385     if (!options)
 386         options = &tmp_opts;
 387
 388     av_assert0(!whitelist ||
 389                !(e=av_dict_get(*options, "protocol_whitelist", NULL, 0)) ||
 390                !strcmp(whitelist, e->value));
 391     av_assert0(!blacklist ||
 392                !(e=av_dict_get(*options, "protocol_blacklist", NULL, 0)) ||
 393                !strcmp(blacklist, e->value));
 394
 395     if ((ret = av_dict_set(options, "protocol_whitelist", whitelist, 0)) < 0)
 396         goto fail;
 397
 398     if ((ret = av_dict_set(options, "protocol_blacklist", blacklist, 0)) < 0)
 399         goto fail;
 400
 401     if ((ret = av_opt_set_dict(*puc, options)) < 0)
 402         goto fail;
 403
 404     ret = ffurl_connect(*puc, options);
 405
 406     if (!ret)
 407         return 0;
 408 fail:
 409     ffurl_closep(puc);
 410     return ret;
 411 }
 412
 413 int ffio_fdopen(AVIOContext **sp, URLContext *h)
 414 {
 415     AVIOContext *s;
 416     uint8_t *buffer = NULL;
 417     int buffer_size, max_packet_size;
 418
 419     max_packet_size = h->max_packet_size;
 420     if (max_packet_size) {
 421         buffer_size = max_packet_size; /* no need to bufferize more than one packet */
 422     } else {
 423         buffer_size = IO_BUFFER_SIZE;
 424     }
 425     if (!(h->flags & AVIO_FLAG_WRITE) && h->is_streamed) {
 426         if (buffer_size > INT_MAX/2)
 427             return AVERROR(EINVAL);
 428         buffer_size *= 2;
 429     }
 430     buffer = av_malloc(buffer_size);
 431     if (!buffer)
 432         return AVERROR(ENOMEM);
 433
 434     *sp = avio_alloc_context(buffer, buffer_size, h->flags & AVIO_FLAG_WRITE, h,
 435                              ffurl_read2, ffurl_write2, ffurl_seek2);
 436     if (!*sp) {
 437         av_freep(&buffer);
 438         return AVERROR(ENOMEM);
 439     }
 440     s = *sp;
 441     if (h->protocol_whitelist) {
 442         s->protocol_whitelist = av_strdup(h->protocol_whitelist);
 443         if (!s->protocol_whitelist) {
 444             avio_closep(sp);
 445             return AVERROR(ENOMEM);
 446         }
 447     }
 448     if (h->protocol_blacklist) {
 449         s->protocol_blacklist = av_strdup(h->protocol_blacklist);
 450         if (!s->protocol_blacklist) {
 451             avio_closep(sp);
 452             return AVERROR(ENOMEM);
 453         }
 454     }
 455     s->direct = h->flags & AVIO_FLAG_DIRECT;
 456
 457     s->seekable = h->is_streamed ? 0 : AVIO_SEEKABLE_NORMAL;
 458     s->max_packet_size = max_packet_size;
 459     s->min_packet_size = h->min_packet_size;
 460     if(h->prot) {
 461         s->read_pause = h->prot->url_read_pause;
 462         s->read_seek  = h->prot->url_read_seek;
 463
 464         if (h->prot->url_read_seek)
 465             s->seekable |= AVIO_SEEKABLE_TIME;
 466     }
 467     ((FFIOContext*)s)->short_seek_get = ffurl_get_short_seek;
 468     s->av_class = &ff_avio_class;
 469     return 0;
 470 }
 471
 472 int ffio_open_whitelist(AVIOContext **s, const char *filename, int flags,
 473                         const AVIOInterruptCB *int_cb, AVDictionary **options,
 474                         const char *whitelist, const char *blacklist)
 475 {
 476     URLContext *h;
 477     int err;
 478
 479     *s = NULL;
 480
 481     err = ffurl_open_whitelist(&h, filename, flags, int_cb, options, whitelist, blacklist, NULL);
 482     if (err < 0)
 483         return err;
 484     err = ffio_fdopen(s, h);
 485     if (err < 0) {
 486         ffurl_close(h);
 487         return err;
 488     }
 489     return 0;
 490 }
 491
 492 int avio_open2(AVIOContext **s, const char *filename, int flags,
 493                const AVIOInterruptCB *int_cb, AVDictionary **options)
 494 {
 495     return ffio_open_whitelist(s, filename, flags, int_cb, options, NULL, NULL);
 496 }
 497
 498 int avio_open(AVIOContext **s, const char *filename, int flags)
 499 {
 500     return avio_open2(s, filename, flags, NULL, NULL);
 501 }
 502
 503
 504 static inline int retry_transfer_wrapper(URLContext *h, uint8_t *buf,
 505                                          const uint8_t *cbuf,
 506                                          int size, int size_min,
 507                                          int read)
 508 {
 509     int ret, len;
 510     int fast_retries = 5;
 511     int64_t wait_since = 0;
 512
 513     len = 0;
 514     while (len < size_min) {
 515         if (ff_check_interrupt(&h->interrupt_callback))
 516             return AVERROR_EXIT;
 517         ret = read ? h->prot->url_read (h, buf + len, size - len):
 518                      h->prot->url_write(h, cbuf + len, size - len);
 519         if (ret == AVERROR(EINTR))
 520             continue;
 521         if (h->flags & AVIO_FLAG_NONBLOCK)
 522             return ret;
 523         if (ret == AVERROR(EAGAIN)) {
 524             ret = 0;
 525             if (fast_retries) {
 526                 fast_retries--;
 527             } else {
 528                 if (h->rw_timeout) {
 529                     if (!wait_since)
 530                         wait_since = av_gettime_relative();
 531                     else if (av_gettime_relative() > wait_since + h->rw_timeout)
 532                         return AVERROR(EIO);
 533                 }
 534                 av_usleep(1000);
 535             }
 536         } else if (ret == AVERROR_EOF)
 537             return (len > 0) ? len : AVERROR_EOF;
 538         else if (ret < 0)
 539             return ret;
 540         if (ret) {
 541             fast_retries = FFMAX(fast_retries, 2);
 542             wait_since = 0;
 543         }
 544         len += ret;
 545     }
 546     return len;
 547 }
 548
 549 int ffurl_read2(void *urlcontext, uint8_t *buf, int size)
 550 {
 551     URLContext *h = urlcontext;
 552
 553     if (!(h->flags & AVIO_FLAG_READ))
 554         return AVERROR(EIO);
 555     return retry_transfer_wrapper(h, buf, NULL, size, 1, 1);
 556 }
 557
 558 int ffurl_read_complete(URLContext *h, unsigned char *buf, int size)
 559 {
 560     if (!(h->flags & AVIO_FLAG_READ))
 561         return AVERROR(EIO);
 562     return retry_transfer_wrapper(h, buf, NULL, size, size, 1);
 563 }
 564
 565 int ffurl_write2(void *urlcontext, const uint8_t *buf, int size)
 566 {
 567     URLContext *h = urlcontext;
 568
 569     if (!(h->flags & AVIO_FLAG_WRITE))
 570         return AVERROR(EIO);
 571     /* avoid sending too big packets */
 572     if (h->max_packet_size && size > h->max_packet_size)
 573         return AVERROR(EIO);
 574
 575     return retry_transfer_wrapper(h, NULL, buf, size, size, 0);
 576 }
 577
 578 int64_t ffurl_seek2(void *urlcontext, int64_t pos, int whence)
 579 {
 580     URLContext *h = urlcontext;
 581     int64_t ret;
 582
 583     if (!h->prot->url_seek)
 584         return AVERROR(ENOSYS);
 585     ret = h->prot->url_seek(h, pos, whence & ~AVSEEK_FORCE);
 586     return ret;
 587 }
 588
 589 int ffurl_closep(URLContext **hh)
 590 {
 591     URLContext *h= *hh;
 592     int ret = 0;
 593     if (!h)
 594         return 0;     /* can happen when ffurl_open fails */
 595
 596     if (h->is_connected && h->prot->url_close)
 597         ret = h->prot->url_close(h);
 598 #if CONFIG_NETWORK
 599     if (h->prot->flags & URL_PROTOCOL_FLAG_NETWORK)
 600         ff_network_close();
 601 #endif
 602     if (h->prot->priv_data_size) {
 603         if (h->prot->priv_data_class)
 604             av_opt_free(h->priv_data);
 605         av_freep(&h->priv_data);
 606     }
 607     av_opt_free(h);
 608     av_freep(hh);
 609     return ret;
 610 }
 611
 612 int ffurl_close(URLContext *h)
 613 {
 614     return ffurl_closep(&h);
 615 }
 616
 617 int avio_close(AVIOContext *s)
 618 {
 619     FFIOContext *const ctx = ffiocontext(s);
 620     URLContext *h;
 621     int ret, error;
 622
 623     if (!s)
 624         return 0;
 625
 626     avio_flush(s);
 627     h         = s->opaque;
 628     s->opaque = NULL;
 629
 630     av_freep(&s->buffer);
 631     if (s->write_flag)
 632         av_log(s, AV_LOG_VERBOSE,
 633                "Statistics: %"PRId64" bytes written, %d seeks, %d writeouts\n",
 634                ctx->bytes_written, ctx->seek_count, ctx->writeout_count);
 635     else
 636         av_log(s, AV_LOG_VERBOSE, "Statistics: %"PRId64" bytes read, %d seeks\n",
 637                ctx->bytes_read, ctx->seek_count);
 638     av_opt_free(s);
 639
 640     error = s->error;
 641     avio_context_free(&s);
 642
 643     ret = ffurl_close(h);
 644     if (ret < 0)
 645         return ret;
 646
 647     return error;
 648 }
 649
 650 int avio_closep(AVIOContext **s)
 651 {
 652     int ret = avio_close(*s);
 653     *s = NULL;
 654     return ret;
 655 }
 656
 657
 658 const char *avio_find_protocol_name(const char *url)
 659 {
 660     const URLProtocol *p = url_find_protocol(url);
 661
 662     return p ? p->name : NULL;
 663 }
 664
 665 int avio_check(const char *url, int flags)
 666 {
 667     URLContext *h;
 668     int ret = ffurl_alloc(&h, url, flags, NULL);
 669     if (ret < 0)
 670         return ret;
 671
 672     if (h->prot->url_check) {
 673         ret = h->prot->url_check(h, flags);
 674     } else {
 675         ret = ffurl_connect(h, NULL);
 676         if (ret >= 0)
 677             ret = flags;
 678     }
 679
 680     ffurl_close(h);
 681     return ret;
 682 }
 683
 684 int ffurl_move(const char *url_src, const char *url_dst)
 685 {
 686     URLContext *h_src, *h_dst;
 687     int ret = ffurl_alloc(&h_src, url_src, AVIO_FLAG_READ_WRITE, NULL);
 688     if (ret < 0)
 689         return ret;
 690     ret = ffurl_alloc(&h_dst, url_dst, AVIO_FLAG_WRITE, NULL);
 691     if (ret < 0) {
 692         ffurl_close(h_src);
 693         return ret;
 694     }
 695
 696     if (h_src->prot == h_dst->prot && h_src->prot->url_move)
 697         ret = h_src->prot->url_move(h_src, h_dst);
 698     else
 699         ret = AVERROR(ENOSYS);
 700
 701     ffurl_close(h_src);
 702     ffurl_close(h_dst);
 703     return ret;
 704 }
 705
 706 int ffurl_delete(const char *url)
 707 {
 708     URLContext *h;
 709     int ret = ffurl_alloc(&h, url, AVIO_FLAG_WRITE, NULL);
 710     if (ret < 0)
 711         return ret;
 712
 713     if (h->prot->url_delete)
 714         ret = h->prot->url_delete(h);
 715     else
 716         ret = AVERROR(ENOSYS);
 717
 718     ffurl_close(h);
 719     return ret;
 720 }
 721
 722 struct AVIODirContext {
 723     struct URLContext *url_context;
 724 };
 725
 726 int avio_open_dir(AVIODirContext **s, const char *url, AVDictionary **options)
 727 {
 728     URLContext *h = NULL;
 729     AVIODirContext *ctx = NULL;
 730     int ret;
 731     av_assert0(s);
 732
 733     ctx = av_mallocz(sizeof(*ctx));
 734     if (!ctx) {
 735         ret = AVERROR(ENOMEM);
 736         goto fail;
 737     }
 738
 739     if ((ret = ffurl_alloc(&h, url, AVIO_FLAG_READ, NULL)) < 0)
 740         goto fail;
 741
 742     if (h->prot->url_open_dir && h->prot->url_read_dir && h->prot->url_close_dir) {
 743         if (options && h->prot->priv_data_class &&
 744             (ret = av_opt_set_dict(h->priv_data, options)) < 0)
 745             goto fail;
 746         ret = h->prot->url_open_dir(h);
 747     } else
 748         ret = AVERROR(ENOSYS);
 749     if (ret < 0)
 750         goto fail;
 751
 752     h->is_connected = 1;
 753     ctx->url_context = h;
 754     *s = ctx;
 755     return 0;
 756
 757   fail:
 758     av_free(ctx);
 759     *s = NULL;
 760     ffurl_close(h);
 761     return ret;
 762 }
 763
 764 int avio_read_dir(AVIODirContext *s, AVIODirEntry **next)
 765 {
 766     URLContext *h;
 767     int ret;
 768
 769     if (!s || !s->url_context)
 770         return AVERROR(EINVAL);
 771     h = s->url_context;
 772     if ((ret = h->prot->url_read_dir(h, next)) < 0)
 773         avio_free_directory_entry(next);
 774     return ret;
 775 }
 776
 777 int avio_close_dir(AVIODirContext **s)
 778 {
 779     URLContext *h;
 780
 781     av_assert0(s);
 782     if (!(*s) || !(*s)->url_context)
 783         return AVERROR(EINVAL);
 784     h = (*s)->url_context;
 785     h->prot->url_close_dir(h);
 786     ffurl_close(h);
 787     av_freep(s);
 788     *s = NULL;
 789     return 0;
 790 }
 791
 792 void avio_free_directory_entry(AVIODirEntry **entry)
 793 {
 794     if (!entry || !*entry)
 795         return;
 796     av_free((*entry)->name);
 797     av_freep(entry);
 798 }
 799
 800 int64_t ffurl_size(URLContext *h)
 801 {
 802     int64_t pos, size;
 803
 804     size = ffurl_seek(h, 0, AVSEEK_SIZE);
 805     if (size < 0) {
 806         pos = ffurl_seek(h, 0, SEEK_CUR);
 807         if ((size = ffurl_seek(h, -1, SEEK_END)) < 0)
 808             return size;
 809         size++;
 810         ffurl_seek(h, pos, SEEK_SET);
 811     }
 812     return size;
 813 }
 814
 815 int ffurl_get_file_handle(URLContext *h)
 816 {
 817     if (!h || !h->prot || !h->prot->url_get_file_handle)
 818         return -1;
 819     return h->prot->url_get_file_handle(h);
 820 }
 821
 822 int ffurl_get_multi_file_handle(URLContext *h, int **handles, int *numhandles)
 823 {
 824     if (!h || !h->prot)
 825         return AVERROR(ENOSYS);
 826     if (!h->prot->url_get_multi_file_handle) {
 827         if (!h->prot->url_get_file_handle)
 828             return AVERROR(ENOSYS);
 829         *handles = av_malloc(sizeof(**handles));
 830         if (!*handles)
 831             return AVERROR(ENOMEM);
 832         *numhandles = 1;
 833         *handles[0] = h->prot->url_get_file_handle(h);
 834         return 0;
 835     }
 836     return h->prot->url_get_multi_file_handle(h, handles, numhandles);
 837 }
 838
 839 int ffurl_get_short_seek(void *urlcontext)
 840 {
 841     URLContext *h = urlcontext;
 842
 843     if (!h || !h->prot || !h->prot->url_get_short_seek)
 844         return AVERROR(ENOSYS);
 845     return h->prot->url_get_short_seek(h);
 846 }
 847
 848 int ffurl_shutdown(URLContext *h, int flags)
 849 {
 850     if (!h || !h->prot || !h->prot->url_shutdown)
 851         return AVERROR(ENOSYS);
 852     return h->prot->url_shutdown(h, flags);
 853 }
 854
 855 int ff_check_interrupt(AVIOInterruptCB *cb)
 856 {
 857     if (cb && cb->callback)
 858         return cb->callback(cb->opaque);
 859     return 0;
 860 }
 861
 862 int ff_rename(const char *url_src, const char *url_dst, void *logctx)
 863 {
 864     int ret = ffurl_move(url_src, url_dst);
 865     if (ret < 0)
 866         av_log(logctx, AV_LOG_ERROR, "failed to rename file %s to %s: %s\n", url_src, url_dst, av_err2str(ret));
 867     return ret;
 868 }