libavformat/avio.c - manifest_repos/ffmpeg - Git at Google

 /*
  * unbuffered I/O
  * Copyright (c) 2001 Fabrice Bellard
  *
  * This file is part of FFmpeg.
  *
  * FFmpeg is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  * License as published by the Free Software Foundation; either
  * version 2.1 of the License, or (at your option) any later version.
  *
  * FFmpeg 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
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General Public
  * License along with FFmpeg; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */

 #include "libavutil/avstring.h"
 #include "libavutil/dict.h"
 #include "libavutil/opt.h"
 #include "libavutil/time.h"
 #include "libavutil/avassert.h"
 #include "os_support.h"
 #include "avformat.h"
 #include "internal.h"
 #if CONFIG_NETWORK
 #include "network.h"
 #endif
 #include "url.h"

 /** @name Logging context. */
 /*@{*/
 static const char *urlcontext_to_name(void *ptr)
 {
     URLContext *h = (URLContext *)ptr;
     if (h->prot)
         return h->prot->name;
     else
         return "NULL";
 }

 static void *urlcontext_child_next(void *obj, void *prev)
 {
     URLContext *h = obj;
     if (!prev && h->priv_data && h->prot->priv_data_class)
         return h->priv_data;
     return NULL;
 }

 #define OFFSET(x) offsetof(URLContext,x)
 #define E AV_OPT_FLAG_ENCODING_PARAM
 #define D AV_OPT_FLAG_DECODING_PARAM
 static const AVOption options[] = {
     {"protocol_whitelist", "List of protocols that are allowed to be used", OFFSET(protocol_whitelist), AV_OPT_TYPE_STRING, { .str = NULL },  0, 0, D },
     {"protocol_blacklist", "List of protocols that are not allowed to be used", OFFSET(protocol_blacklist), AV_OPT_TYPE_STRING, { .str = NULL },  0, 0, D },
     {"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 },
     { NULL }
 };

 const AVClass ffurl_context_class = {
     .class_name       = "URLContext",
     .item_name        = urlcontext_to_name,
     .option           = options,
     .version          = LIBAVUTIL_VERSION_INT,
     .child_next       = urlcontext_child_next,
 #if FF_API_CHILD_CLASS_NEXT
     .child_class_next = ff_urlcontext_child_class_next,
 #endif
     .child_class_iterate = ff_urlcontext_child_class_iterate,
 };
 /*@}*/

 static int url_alloc_for_protocol(URLContext **puc, const URLProtocol *up,
                                   const char *filename, int flags,
                                   const AVIOInterruptCB *int_cb)
 {
     URLContext *uc;
     int err;

 #if CONFIG_NETWORK
     if (up->flags & URL_PROTOCOL_FLAG_NETWORK && !ff_network_init())
         return AVERROR(EIO);
 #endif
     if ((flags & AVIO_FLAG_READ) && !up->url_read) {
         av_log(NULL, AV_LOG_ERROR,
                "Impossible to open the '%s' protocol for reading\n", up->name);
         return AVERROR(EIO);
     }
     if ((flags & AVIO_FLAG_WRITE) && !up->url_write) {
         av_log(NULL, AV_LOG_ERROR,
                "Impossible to open the '%s' protocol for writing\n", up->name);
         return AVERROR(EIO);
     }
     uc = av_mallocz(sizeof(URLContext) + strlen(filename) + 1);
     if (!uc) {
         err = AVERROR(ENOMEM);
         goto fail;
     }
     uc->av_class = &ffurl_context_class;
     uc->filename = (char *)&uc[1];
     strcpy(uc->filename, filename);
     uc->prot            = up;
     uc->flags           = flags;
     uc->is_streamed     = 0; /* default = not streamed */
     uc->max_packet_size = 0; /* default: stream file */
     if (up->priv_data_size) {
         uc->priv_data = av_mallocz(up->priv_data_size);
         if (!uc->priv_data) {
             err = AVERROR(ENOMEM);
             goto fail;
         }
         if (up->priv_data_class) {
             int proto_len= strlen(up->name);
             char *start = strchr(uc->filename, ',');
             *(const AVClass **)uc->priv_data = up->priv_data_class;
             av_opt_set_defaults(uc->priv_data);
             if(!strncmp(up->name, uc->filename, proto_len) && uc->filename + proto_len == start){
                 int ret= 0;
                 char *p= start;
                 char sep= *++p;
                 char *key, *val;
                 p++;

                 if (strcmp(up->name, "subfile"))
                     ret = AVERROR(EINVAL);

                 while(ret >= 0 && (key= strchr(p, sep)) && p<key && (val = strchr(key+1, sep))){
                     *val= *key= 0;
                     if (strcmp(p, "start") && strcmp(p, "end")) {
                         ret = AVERROR_OPTION_NOT_FOUND;
                     } else
                         ret= av_opt_set(uc->priv_data, p, key+1, 0);
                     if (ret == AVERROR_OPTION_NOT_FOUND)
                         av_log(uc, AV_LOG_ERROR, "Key '%s' not found.\n", p);
                     *val= *key= sep;
                     p= val+1;
                 }
                 if(ret<0 || p!=key){
                     av_log(uc, AV_LOG_ERROR, "Error parsing options string %s\n", start);
                     av_freep(&uc->priv_data);
                     av_freep(&uc);
                     err = AVERROR(EINVAL);
                     goto fail;
                 }
                 memmove(start, key+1, strlen(key));
             }
         }
     }
     if (int_cb)
         uc->interrupt_callback = *int_cb;

     *puc = uc;
     return 0;
 fail:
     *puc = NULL;
     if (uc)
         av_freep(&uc->priv_data);
     av_freep(&uc);
 #if CONFIG_NETWORK
     if (up->flags & URL_PROTOCOL_FLAG_NETWORK)
         ff_network_close();
 #endif
     return err;
 }

 int ffurl_connect(URLContext *uc, AVDictionary **options)
 {
     int err;
     AVDictionary *tmp_opts = NULL;
     AVDictionaryEntry *e;

     if (!options)
         options = &tmp_opts;

     // Check that URLContext was initialized correctly and lists are matching if set
     av_assert0(!(e=av_dict_get(*options, "protocol_whitelist", NULL, 0)) ||
                (uc->protocol_whitelist && !strcmp(uc->protocol_whitelist, e->value)));
     av_assert0(!(e=av_dict_get(*options, "protocol_blacklist", NULL, 0)) ||
                (uc->protocol_blacklist && !strcmp(uc->protocol_blacklist, e->value)));

     if (uc->protocol_whitelist && av_match_list(uc->prot->name, uc->protocol_whitelist, ',') <= 0) {
         av_log(uc, AV_LOG_ERROR, "Protocol '%s' not on whitelist '%s'!\n", uc->prot->name, uc->protocol_whitelist);
         return AVERROR(EINVAL);
     }

     if (uc->protocol_blacklist && av_match_list(uc->prot->name, uc->protocol_blacklist, ',') > 0) {
         av_log(uc, AV_LOG_ERROR, "Protocol '%s' on blacklist '%s'!\n", uc->prot->name, uc->protocol_blacklist);
         return AVERROR(EINVAL);
     }

     if (!uc->protocol_whitelist && uc->prot->default_whitelist) {
         av_log(uc, AV_LOG_DEBUG, "Setting default whitelist '%s'\n", uc->prot->default_whitelist);
         uc->protocol_whitelist = av_strdup(uc->prot->default_whitelist);
         if (!uc->protocol_whitelist) {
             return AVERROR(ENOMEM);
         }
     } else if (!uc->protocol_whitelist)
         av_log(uc, AV_LOG_DEBUG, "No default whitelist set\n"); // This should be an error once all declare a default whitelist

     if ((err = av_dict_set(options, "protocol_whitelist", uc->protocol_whitelist, 0)) < 0)
         return err;
     if ((err = av_dict_set(options, "protocol_blacklist", uc->protocol_blacklist, 0)) < 0)
         return err;

     err =
         uc->prot->url_open2 ? uc->prot->url_open2(uc,
                                                   uc->filename,
                                                   uc->flags,
                                                   options) :
         uc->prot->url_open(uc, uc->filename, uc->flags);

     av_dict_set(options, "protocol_whitelist", NULL, 0);
     av_dict_set(options, "protocol_blacklist", NULL, 0);

     if (err)
         return err;
     uc->is_connected = 1;
     /* We must be careful here as ffurl_seek() could be slow,
      * for example for http */
     if ((uc->flags & AVIO_FLAG_WRITE) || !strcmp(uc->prot->name, "file"))
         if (!uc->is_streamed && ffurl_seek(uc, 0, SEEK_SET) < 0)
             uc->is_streamed = 1;
     return 0;
 }

 int ffurl_accept(URLContext *s, URLContext **c)
 {
     av_assert0(!*c);
     if (s->prot->url_accept)
         return s->prot->url_accept(s, c);
     return AVERROR(EBADF);
 }

 int ffurl_handshake(URLContext *c)
 {
     int ret;
     if (c->prot->url_handshake) {
         ret = c->prot->url_handshake(c);
         if (ret)
             return ret;
     }
     c->is_connected = 1;
     return 0;
 }

 #define URL_SCHEME_CHARS                        \
     "abcdefghijklmnopqrstuvwxyz"                \
     "ABCDEFGHIJKLMNOPQRSTUVWXYZ"                \
     "0123456789+-."

 static const struct URLProtocol *url_find_protocol(const char *filename)
 {
     const URLProtocol **protocols;
     char proto_str[128], proto_nested[128], *ptr;
     size_t proto_len = strspn(filename, URL_SCHEME_CHARS);
     int i;

     if (filename[proto_len] != ':' &&
         (strncmp(filename, "subfile,", 8) || !strchr(filename + proto_len + 1, ':')) ||
         is_dos_path(filename))
         strcpy(proto_str, "file");
     else
         av_strlcpy(proto_str, filename,
                    FFMIN(proto_len + 1, sizeof(proto_str)));

     av_strlcpy(proto_nested, proto_str, sizeof(proto_nested));
     if ((ptr = strchr(proto_nested, '+')))
         *ptr = '\0';

     protocols = ffurl_get_protocols(NULL, NULL);
     if (!protocols)
         return NULL;
     for (i = 0; protocols[i]; i++) {
             const URLProtocol *up = protocols[i];
         if (!strcmp(proto_str, up->name)) {
             av_freep(&protocols);
             return up;
         }
         if (up->flags & URL_PROTOCOL_FLAG_NESTED_SCHEME &&
             !strcmp(proto_nested, up->name)) {
             av_freep(&protocols);
             return up;
         }
     }
     av_freep(&protocols);
     if (av_strstart(filename, "https:", NULL) || av_strstart(filename, "tls:", NULL))
         av_log(NULL, AV_LOG_WARNING, "https protocol not found, recompile FFmpeg with "
                                      "openssl, gnutls or securetransport enabled.\n");

     return NULL;
 }

 int ffurl_alloc(URLContext **puc, const char *filename, int flags,
                 const AVIOInterruptCB *int_cb)
 {
     const URLProtocol *p = NULL;

     p = url_find_protocol(filename);
     if (p)
        return url_alloc_for_protocol(puc, p, filename, flags, int_cb);

     *puc = NULL;
     return AVERROR_PROTOCOL_NOT_FOUND;
 }

 int ffurl_open_whitelist(URLContext **puc, const char *filename, int flags,
                          const AVIOInterruptCB *int_cb, AVDictionary **options,
                          const char *whitelist, const char* blacklist,
                          URLContext *parent)
 {
     AVDictionary *tmp_opts = NULL;
     AVDictionaryEntry *e;
     int ret = ffurl_alloc(puc, filename, flags, int_cb);
     if (ret < 0)
         return ret;
     if (parent)
         av_opt_copy(*puc, parent);
     if (options &&
         (ret = av_opt_set_dict(*puc, options)) < 0)
         goto fail;
     if (options && (*puc)->prot->priv_data_class &&
         (ret = av_opt_set_dict((*puc)->priv_data, options)) < 0)
         goto fail;

     if (!options)
         options = &tmp_opts;

     av_assert0(!whitelist ||
                !(e=av_dict_get(*options, "protocol_whitelist", NULL, 0)) ||
                !strcmp(whitelist, e->value));
     av_assert0(!blacklist ||
                !(e=av_dict_get(*options, "protocol_blacklist", NULL, 0)) ||
                !strcmp(blacklist, e->value));

     if ((ret = av_dict_set(options, "protocol_whitelist", whitelist, 0)) < 0)
         goto fail;

     if ((ret = av_dict_set(options, "protocol_blacklist", blacklist, 0)) < 0)
         goto fail;

     if ((ret = av_opt_set_dict(*puc, options)) < 0)
         goto fail;

     ret = ffurl_connect(*puc, options);

     if (!ret)
         return 0;
 fail:
     ffurl_closep(puc);
     return ret;
 }

 int ffurl_open(URLContext **puc, const char *filename, int flags,
                const AVIOInterruptCB *int_cb, AVDictionary **options)
 {
     return ffurl_open_whitelist(puc, filename, flags,
                                 int_cb, options, NULL, NULL, NULL);
 }

 static inline int retry_transfer_wrapper(URLContext *h, uint8_t *buf,
                                          int size, int size_min,
                                          int (*transfer_func)(URLContext *h,
                                                               uint8_t *buf,
                                                               int size))
 {
     int ret, len;
     int fast_retries = 5;
     int64_t wait_since = 0;

     len = 0;
     while (len < size_min) {
         if (ff_check_interrupt(&h->interrupt_callback))
             return AVERROR_EXIT;
         ret = transfer_func(h, buf + len, size - len);
         if (ret == AVERROR(EINTR))
             continue;
         if (h->flags & AVIO_FLAG_NONBLOCK)
             return ret;
         if (ret == AVERROR(EAGAIN)) {
             ret = 0;
             if (fast_retries) {
                 fast_retries--;
             } else {
                 if (h->rw_timeout) {
                     if (!wait_since)
                         wait_since = av_gettime_relative();
                     else if (av_gettime_relative() > wait_since + h->rw_timeout)
                         return AVERROR(EIO);
                 }
                 av_usleep(1000);
             }
         } else if (ret == AVERROR_EOF)
             return (len > 0) ? len : AVERROR_EOF;
         else if (ret < 0)
             return ret;
         if (ret) {
             fast_retries = FFMAX(fast_retries, 2);
             wait_since = 0;
         }
         len += ret;
     }
     return len;
 }

 int ffurl_read(URLContext *h, unsigned char *buf, int size)
 {
     if (!(h->flags & AVIO_FLAG_READ))
         return AVERROR(EIO);
     return retry_transfer_wrapper(h, buf, size, 1, h->prot->url_read);
 }

 int ffurl_read_complete(URLContext *h, unsigned char *buf, int size)
 {
     if (!(h->flags & AVIO_FLAG_READ))
         return AVERROR(EIO);
     return retry_transfer_wrapper(h, buf, size, size, h->prot->url_read);
 }

 int ffurl_write(URLContext *h, const unsigned char *buf, int size)
 {
     if (!(h->flags & AVIO_FLAG_WRITE))
         return AVERROR(EIO);
     /* avoid sending too big packets */
     if (h->max_packet_size && size > h->max_packet_size)
         return AVERROR(EIO);

     return retry_transfer_wrapper(h, (unsigned char *)buf, size, size,
                                   (int (*)(struct URLContext *, uint8_t *, int))
                                   h->prot->url_write);
 }

 int64_t ffurl_seek(URLContext *h, int64_t pos, int whence)
 {
     int64_t ret;

     if (!h->prot->url_seek)
         return AVERROR(ENOSYS);
     ret = h->prot->url_seek(h, pos, whence & ~AVSEEK_FORCE);
     return ret;
 }

 int ffurl_closep(URLContext **hh)
 {
     URLContext *h= *hh;
     int ret = 0;
     if (!h)
         return 0;     /* can happen when ffurl_open fails */

     if (h->is_connected && h->prot->url_close)
         ret = h->prot->url_close(h);
 #if CONFIG_NETWORK
     if (h->prot->flags & URL_PROTOCOL_FLAG_NETWORK)
         ff_network_close();
 #endif
     if (h->prot->priv_data_size) {
         if (h->prot->priv_data_class)
             av_opt_free(h->priv_data);
         av_freep(&h->priv_data);
     }
     av_opt_free(h);
     av_freep(hh);
     return ret;
 }

 int ffurl_close(URLContext *h)
 {
     return ffurl_closep(&h);
 }


 const char *avio_find_protocol_name(const char *url)
 {
     const URLProtocol *p = url_find_protocol(url);

     return p ? p->name : NULL;
 }

 int avio_check(const char *url, int flags)
 {
     URLContext *h;
     int ret = ffurl_alloc(&h, url, flags, NULL);
     if (ret < 0)
         return ret;

     if (h->prot->url_check) {
         ret = h->prot->url_check(h, flags);
     } else {
         ret = ffurl_connect(h, NULL);
         if (ret >= 0)
             ret = flags;
     }

     ffurl_close(h);
     return ret;
 }

 int avpriv_io_move(const char *url_src, const char *url_dst)
 {
     URLContext *h_src, *h_dst;
     int ret = ffurl_alloc(&h_src, url_src, AVIO_FLAG_READ_WRITE, NULL);
     if (ret < 0)
         return ret;
     ret = ffurl_alloc(&h_dst, url_dst, AVIO_FLAG_WRITE, NULL);
     if (ret < 0) {
         ffurl_close(h_src);
         return ret;
     }

     if (h_src->prot == h_dst->prot && h_src->prot->url_move)
         ret = h_src->prot->url_move(h_src, h_dst);
     else
         ret = AVERROR(ENOSYS);

     ffurl_close(h_src);
     ffurl_close(h_dst);
     return ret;
 }

 int avpriv_io_delete(const char *url)
 {
     URLContext *h;
     int ret = ffurl_alloc(&h, url, AVIO_FLAG_WRITE, NULL);
     if (ret < 0)
         return ret;

     if (h->prot->url_delete)
         ret = h->prot->url_delete(h);
     else
         ret = AVERROR(ENOSYS);

     ffurl_close(h);
     return ret;
 }

 int avio_open_dir(AVIODirContext **s, const char *url, AVDictionary **options)
 {
     URLContext *h = NULL;
     AVIODirContext *ctx = NULL;
     int ret;
     av_assert0(s);

     ctx = av_mallocz(sizeof(*ctx));
     if (!ctx) {
         ret = AVERROR(ENOMEM);
         goto fail;
     }

     if ((ret = ffurl_alloc(&h, url, AVIO_FLAG_READ, NULL)) < 0)
         goto fail;

     if (h->prot->url_open_dir && h->prot->url_read_dir && h->prot->url_close_dir) {
         if (options && h->prot->priv_data_class &&
             (ret = av_opt_set_dict(h->priv_data, options)) < 0)
             goto fail;
         ret = h->prot->url_open_dir(h);
     } else
         ret = AVERROR(ENOSYS);
     if (ret < 0)
         goto fail;

     h->is_connected = 1;
     ctx->url_context = h;
     *s = ctx;
     return 0;

   fail:
     av_free(ctx);
     *s = NULL;
     ffurl_close(h);
     return ret;
 }

 int avio_read_dir(AVIODirContext *s, AVIODirEntry **next)
 {
     URLContext *h;
     int ret;

     if (!s || !s->url_context)
         return AVERROR(EINVAL);
     h = s->url_context;
     if ((ret = h->prot->url_read_dir(h, next)) < 0)
         avio_free_directory_entry(next);
     return ret;
 }

 int avio_close_dir(AVIODirContext **s)
 {
     URLContext *h;

     av_assert0(s);
     if (!(*s) || !(*s)->url_context)
         return AVERROR(EINVAL);
     h = (*s)->url_context;
     h->prot->url_close_dir(h);
     ffurl_close(h);
     av_freep(s);
     *s = NULL;
     return 0;
 }

 void avio_free_directory_entry(AVIODirEntry **entry)
 {
     if (!entry || !*entry)
         return;
     av_free((*entry)->name);
     av_freep(entry);
 }

 int64_t ffurl_size(URLContext *h)
 {
     int64_t pos, size;

     size = ffurl_seek(h, 0, AVSEEK_SIZE);
     if (size < 0) {
         pos = ffurl_seek(h, 0, SEEK_CUR);
         if ((size = ffurl_seek(h, -1, SEEK_END)) < 0)
             return size;
         size++;
         ffurl_seek(h, pos, SEEK_SET);
     }
     return size;
 }

 int ffurl_get_file_handle(URLContext *h)
 {
     if (!h || !h->prot || !h->prot->url_get_file_handle)
         return -1;
     return h->prot->url_get_file_handle(h);
 }

 int ffurl_get_multi_file_handle(URLContext *h, int **handles, int *numhandles)
 {
     if (!h || !h->prot)
         return AVERROR(ENOSYS);
     if (!h->prot->url_get_multi_file_handle) {
         if (!h->prot->url_get_file_handle)
             return AVERROR(ENOSYS);
         *handles = av_malloc(sizeof(**handles));
         if (!*handles)
             return AVERROR(ENOMEM);
         *numhandles = 1;
         *handles[0] = h->prot->url_get_file_handle(h);
         return 0;
     }
     return h->prot->url_get_multi_file_handle(h, handles, numhandles);
 }

 int ffurl_get_short_seek(URLContext *h)
 {
     if (!h || !h->prot || !h->prot->url_get_short_seek)
         return AVERROR(ENOSYS);
     return h->prot->url_get_short_seek(h);
 }

 int ffurl_shutdown(URLContext *h, int flags)
 {
     if (!h || !h->prot || !h->prot->url_shutdown)
         return AVERROR(ENOSYS);
     return h->prot->url_shutdown(h, flags);
 }

 int ff_check_interrupt(AVIOInterruptCB *cb)
 {
     if (cb && cb->callback)
         return cb->callback(cb->opaque);
     return 0;
 }

 int ff_rename(const char *url_src, const char *url_dst, void *logctx)
 {
     int ret = avpriv_io_move(url_src, url_dst);
     if (ret < 0)
         av_log(logctx, AV_LOG_ERROR, "failed to rename file %s to %s: %s\n", url_src, url_dst, av_err2str(ret));
     return ret;
 }
	/*
	* unbuffered I/O
	* Copyright (c) 2001 Fabrice Bellard
	*
	* This file is part of FFmpeg.
	*
	* FFmpeg is free software; you can redistribute it and/or
	* modify it under the terms of the GNU Lesser General Public
	* License as published by the Free Software Foundation; either
	* version 2.1 of the License, or (at your option) any later version.
	*
	* FFmpeg 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
	* Lesser General Public License for more details.
	*
	* You should have received a copy of the GNU Lesser General Public
	* License along with FFmpeg; if not, write to the Free Software
	* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
	*/

	#include "libavutil/avstring.h"
	#include "libavutil/dict.h"
	#include "libavutil/opt.h"
	#include "libavutil/time.h"
	#include "libavutil/avassert.h"
	#include "os_support.h"
	#include "avformat.h"
	#include "internal.h"
	#if CONFIG_NETWORK
	#include "network.h"
	#endif
	#include "url.h"

	/** @name Logging context. */
	/@{/
	static const char urlcontext_to_name(void ptr)
	{
	URLContext h = (URLContext )ptr;
	if (h->prot)
	return h->prot->name;
	else
	return "NULL";
	}

	static void urlcontext_child_next(void obj, void *prev)
	{
	URLContext *h = obj;
	if (!prev && h->priv_data && h->prot->priv_data_class)
	return h->priv_data;
	return NULL;
	}

	#define OFFSET(x) offsetof(URLContext,x)
	#define E AV_OPT_FLAG_ENCODING_PARAM
	#define D AV_OPT_FLAG_DECODING_PARAM
	static const AVOption options[] = {
	{"protocol_whitelist", "List of protocols that are allowed to be used", OFFSET(protocol_whitelist), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, D },
	{"protocol_blacklist", "List of protocols that are not allowed to be used", OFFSET(protocol_blacklist), AV_OPT_TYPE_STRING, { .str = NULL }, 0, 0, D },
	{"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 },
	{ NULL }
	};

	const AVClass ffurl_context_class = {
	.class_name = "URLContext",
	.item_name = urlcontext_to_name,
	.option = options,
	.version = LIBAVUTIL_VERSION_INT,
	.child_next = urlcontext_child_next,
	#if FF_API_CHILD_CLASS_NEXT
	.child_class_next = ff_urlcontext_child_class_next,
	#endif
	.child_class_iterate = ff_urlcontext_child_class_iterate,
	};
	/@}/

	static int url_alloc_for_protocol(URLContext *puc, const URLProtocol up,
	const char *filename, int flags,
	const AVIOInterruptCB *int_cb)
	{
	URLContext *uc;
	int err;

	#if CONFIG_NETWORK
	if (up->flags & URL_PROTOCOL_FLAG_NETWORK && !ff_network_init())
	return AVERROR(EIO);
	#endif
	if ((flags & AVIO_FLAG_READ) && !up->url_read) {
	av_log(NULL, AV_LOG_ERROR,
	"Impossible to open the '%s' protocol for reading\n", up->name);
	return AVERROR(EIO);
	}
	if ((flags & AVIO_FLAG_WRITE) && !up->url_write) {
	av_log(NULL, AV_LOG_ERROR,
	"Impossible to open the '%s' protocol for writing\n", up->name);
	return AVERROR(EIO);
	}
	uc = av_mallocz(sizeof(URLContext) + strlen(filename) + 1);
	if (!uc) {
	err = AVERROR(ENOMEM);
	goto fail;
	}
	uc->av_class = &ffurl_context_class;
	uc->filename = (char *)&uc[1];
	strcpy(uc->filename, filename);
	uc->prot = up;
	uc->flags = flags;
	uc->is_streamed = 0; /* default = not streamed */
	uc->max_packet_size = 0; /* default: stream file */
	if (up->priv_data_size) {
	uc->priv_data = av_mallocz(up->priv_data_size);
	if (!uc->priv_data) {
	err = AVERROR(ENOMEM);
	goto fail;
	}
	if (up->priv_data_class) {
	int proto_len= strlen(up->name);
	char *start = strchr(uc->filename, ',');
	(const AVClass *)uc->priv_data = up->priv_data_class;
	av_opt_set_defaults(uc->priv_data);
	if(!strncmp(up->name, uc->filename, proto_len) && uc->filename + proto_len == start){
	int ret= 0;
	char *p= start;
	char sep= *++p;
	char key, val;
	p++;

	if (strcmp(up->name, "subfile"))
	ret = AVERROR(EINVAL);

	while(ret >= 0 && (key= strchr(p, sep)) && p<key && (val = strchr(key+1, sep))){
	val= key= 0;
	if (strcmp(p, "start") && strcmp(p, "end")) {
	ret = AVERROR_OPTION_NOT_FOUND;
	} else
	ret= av_opt_set(uc->priv_data, p, key+1, 0);
	if (ret == AVERROR_OPTION_NOT_FOUND)
	av_log(uc, AV_LOG_ERROR, "Key '%s' not found.\n", p);
	val= key= sep;
	p= val+1;
	}
	if(ret<0 \|\| p!=key){
	av_log(uc, AV_LOG_ERROR, "Error parsing options string %s\n", start);
	av_freep(&uc->priv_data);
	av_freep(&uc);
	err = AVERROR(EINVAL);
	goto fail;
	}
	memmove(start, key+1, strlen(key));
	}
	}
	}
	if (int_cb)
	uc->interrupt_callback = *int_cb;

	*puc = uc;
	return 0;
	fail:
	*puc = NULL;
	if (uc)
	av_freep(&uc->priv_data);
	av_freep(&uc);
	#if CONFIG_NETWORK
	if (up->flags & URL_PROTOCOL_FLAG_NETWORK)
	ff_network_close();
	#endif
	return err;
	}

	int ffurl_connect(URLContext uc, AVDictionary *options)
	{
	int err;
	AVDictionary *tmp_opts = NULL;
	AVDictionaryEntry *e;

	if (!options)
	options = &tmp_opts;

	// Check that URLContext was initialized correctly and lists are matching if set
	av_assert0(!(e=av_dict_get(*options, "protocol_whitelist", NULL, 0)) \|\|
	(uc->protocol_whitelist && !strcmp(uc->protocol_whitelist, e->value)));
	av_assert0(!(e=av_dict_get(*options, "protocol_blacklist", NULL, 0)) \|\|
	(uc->protocol_blacklist && !strcmp(uc->protocol_blacklist, e->value)));

	if (uc->protocol_whitelist && av_match_list(uc->prot->name, uc->protocol_whitelist, ',') <= 0) {
	av_log(uc, AV_LOG_ERROR, "Protocol '%s' not on whitelist '%s'!\n", uc->prot->name, uc->protocol_whitelist);
	return AVERROR(EINVAL);
	}

	if (uc->protocol_blacklist && av_match_list(uc->prot->name, uc->protocol_blacklist, ',') > 0) {
	av_log(uc, AV_LOG_ERROR, "Protocol '%s' on blacklist '%s'!\n", uc->prot->name, uc->protocol_blacklist);
	return AVERROR(EINVAL);
	}

	if (!uc->protocol_whitelist && uc->prot->default_whitelist) {
	av_log(uc, AV_LOG_DEBUG, "Setting default whitelist '%s'\n", uc->prot->default_whitelist);
	uc->protocol_whitelist = av_strdup(uc->prot->default_whitelist);
	if (!uc->protocol_whitelist) {
	return AVERROR(ENOMEM);
	}
	} else if (!uc->protocol_whitelist)
	av_log(uc, AV_LOG_DEBUG, "No default whitelist set\n"); // This should be an error once all declare a default whitelist

	if ((err = av_dict_set(options, "protocol_whitelist", uc->protocol_whitelist, 0)) < 0)
	return err;
	if ((err = av_dict_set(options, "protocol_blacklist", uc->protocol_blacklist, 0)) < 0)
	return err;

	err =
	uc->prot->url_open2 ? uc->prot->url_open2(uc,
	uc->filename,
	uc->flags,
	options) :
	uc->prot->url_open(uc, uc->filename, uc->flags);

	av_dict_set(options, "protocol_whitelist", NULL, 0);
	av_dict_set(options, "protocol_blacklist", NULL, 0);

	if (err)
	return err;
	uc->is_connected = 1;
	/* We must be careful here as ffurl_seek() could be slow,
	* for example for http */
	if ((uc->flags & AVIO_FLAG_WRITE) \|\| !strcmp(uc->prot->name, "file"))
	if (!uc->is_streamed && ffurl_seek(uc, 0, SEEK_SET) < 0)
	uc->is_streamed = 1;
	return 0;
	}

	int ffurl_accept(URLContext s, URLContext *c)
	{
	av_assert0(!*c);
	if (s->prot->url_accept)
	return s->prot->url_accept(s, c);
	return AVERROR(EBADF);
	}

	int ffurl_handshake(URLContext *c)
	{
	int ret;
	if (c->prot->url_handshake) {
	ret = c->prot->url_handshake(c);
	if (ret)
	return ret;
	}
	c->is_connected = 1;
	return 0;
	}

	#define URL_SCHEME_CHARS \
	"abcdefghijklmnopqrstuvwxyz" \
	"ABCDEFGHIJKLMNOPQRSTUVWXYZ" \
	"0123456789+-."

	static const struct URLProtocol url_find_protocol(const char filename)
	{
	const URLProtocol **protocols;
	char proto_str[128], proto_nested[128], *ptr;
	size_t proto_len = strspn(filename, URL_SCHEME_CHARS);
	int i;

	if (filename[proto_len] != ':' &&
	(strncmp(filename, "subfile,", 8) \|\| !strchr(filename + proto_len + 1, ':')) \|\|
	is_dos_path(filename))
	strcpy(proto_str, "file");
	else
	av_strlcpy(proto_str, filename,
	FFMIN(proto_len + 1, sizeof(proto_str)));

	av_strlcpy(proto_nested, proto_str, sizeof(proto_nested));
	if ((ptr = strchr(proto_nested, '+')))
	*ptr = '\0';

	protocols = ffurl_get_protocols(NULL, NULL);
	if (!protocols)
	return NULL;
	for (i = 0; protocols[i]; i++) {
	const URLProtocol *up = protocols[i];
	if (!strcmp(proto_str, up->name)) {
	av_freep(&protocols);
	return up;
	}
	if (up->flags & URL_PROTOCOL_FLAG_NESTED_SCHEME &&
	!strcmp(proto_nested, up->name)) {
	av_freep(&protocols);
	return up;
	}
	}
	av_freep(&protocols);
	if (av_strstart(filename, "https:", NULL) \|\| av_strstart(filename, "tls:", NULL))
	av_log(NULL, AV_LOG_WARNING, "https protocol not found, recompile FFmpeg with "
	"openssl, gnutls or securetransport enabled.\n");

	return NULL;
	}

	int ffurl_alloc(URLContext *puc, const char filename, int flags,
	const AVIOInterruptCB *int_cb)
	{
	const URLProtocol *p = NULL;

	p = url_find_protocol(filename);
	if (p)
	return url_alloc_for_protocol(puc, p, filename, flags, int_cb);

	*puc = NULL;
	return AVERROR_PROTOCOL_NOT_FOUND;
	}

	int ffurl_open_whitelist(URLContext *puc, const char filename, int flags,
	const AVIOInterruptCB int_cb, AVDictionary *options,
	const char whitelist, const char blacklist,
	URLContext *parent)
	{
	AVDictionary *tmp_opts = NULL;
	AVDictionaryEntry *e;
	int ret = ffurl_alloc(puc, filename, flags, int_cb);
	if (ret < 0)
	return ret;
	if (parent)
	av_opt_copy(*puc, parent);
	if (options &&
	(ret = av_opt_set_dict(*puc, options)) < 0)
	goto fail;
	if (options && (*puc)->prot->priv_data_class &&
	(ret = av_opt_set_dict((*puc)->priv_data, options)) < 0)
	goto fail;

	if (!options)
	options = &tmp_opts;

	av_assert0(!whitelist \|\|
	!(e=av_dict_get(*options, "protocol_whitelist", NULL, 0)) \|\|
	!strcmp(whitelist, e->value));
	av_assert0(!blacklist \|\|
	!(e=av_dict_get(*options, "protocol_blacklist", NULL, 0)) \|\|
	!strcmp(blacklist, e->value));

	if ((ret = av_dict_set(options, "protocol_whitelist", whitelist, 0)) < 0)
	goto fail;

	if ((ret = av_dict_set(options, "protocol_blacklist", blacklist, 0)) < 0)
	goto fail;

	if ((ret = av_opt_set_dict(*puc, options)) < 0)
	goto fail;

	ret = ffurl_connect(*puc, options);

	if (!ret)
	return 0;
	fail:
	ffurl_closep(puc);
	return ret;
	}

	int ffurl_open(URLContext *puc, const char filename, int flags,
	const AVIOInterruptCB int_cb, AVDictionary *options)
	{
	return ffurl_open_whitelist(puc, filename, flags,
	int_cb, options, NULL, NULL, NULL);
	}

	static inline int retry_transfer_wrapper(URLContext h, uint8_t buf,
	int size, int size_min,
	int (transfer_func)(URLContext h,
	uint8_t *buf,
	int size))
	{
	int ret, len;
	int fast_retries = 5;
	int64_t wait_since = 0;

	len = 0;
	while (len < size_min) {
	if (ff_check_interrupt(&h->interrupt_callback))
	return AVERROR_EXIT;
	ret = transfer_func(h, buf + len, size - len);
	if (ret == AVERROR(EINTR))
	continue;
	if (h->flags & AVIO_FLAG_NONBLOCK)
	return ret;
	if (ret == AVERROR(EAGAIN)) {
	ret = 0;
	if (fast_retries) {
	fast_retries--;
	} else {
	if (h->rw_timeout) {
	if (!wait_since)
	wait_since = av_gettime_relative();
	else if (av_gettime_relative() > wait_since + h->rw_timeout)
	return AVERROR(EIO);
	}
	av_usleep(1000);
	}
	} else if (ret == AVERROR_EOF)
	return (len > 0) ? len : AVERROR_EOF;
	else if (ret < 0)
	return ret;
	if (ret) {
	fast_retries = FFMAX(fast_retries, 2);
	wait_since = 0;
	}
	len += ret;
	}
	return len;
	}

	int ffurl_read(URLContext h, unsigned char buf, int size)
	{
	if (!(h->flags & AVIO_FLAG_READ))
	return AVERROR(EIO);
	return retry_transfer_wrapper(h, buf, size, 1, h->prot->url_read);
	}

	int ffurl_read_complete(URLContext h, unsigned char buf, int size)
	{
	if (!(h->flags & AVIO_FLAG_READ))
	return AVERROR(EIO);
	return retry_transfer_wrapper(h, buf, size, size, h->prot->url_read);
	}

	int ffurl_write(URLContext h, const unsigned char buf, int size)
	{
	if (!(h->flags & AVIO_FLAG_WRITE))
	return AVERROR(EIO);
	/* avoid sending too big packets */
	if (h->max_packet_size && size > h->max_packet_size)
	return AVERROR(EIO);

	return retry_transfer_wrapper(h, (unsigned char *)buf, size, size,
	(int ()(struct URLContext , uint8_t *, int))
	h->prot->url_write);
	}

	int64_t ffurl_seek(URLContext *h, int64_t pos, int whence)
	{
	int64_t ret;

	if (!h->prot->url_seek)
	return AVERROR(ENOSYS);
	ret = h->prot->url_seek(h, pos, whence & ~AVSEEK_FORCE);
	return ret;
	}

	int ffurl_closep(URLContext **hh)
	{
	URLContext h= hh;
	int ret = 0;
	if (!h)
	return 0; /* can happen when ffurl_open fails */

	if (h->is_connected && h->prot->url_close)
	ret = h->prot->url_close(h);
	#if CONFIG_NETWORK
	if (h->prot->flags & URL_PROTOCOL_FLAG_NETWORK)
	ff_network_close();
	#endif
	if (h->prot->priv_data_size) {
	if (h->prot->priv_data_class)
	av_opt_free(h->priv_data);
	av_freep(&h->priv_data);
	}
	av_opt_free(h);
	av_freep(hh);
	return ret;
	}

	int ffurl_close(URLContext *h)
	{
	return ffurl_closep(&h);
	}


	const char avio_find_protocol_name(const char url)
	{
	const URLProtocol *p = url_find_protocol(url);

	return p ? p->name : NULL;
	}

	int avio_check(const char *url, int flags)
	{
	URLContext *h;
	int ret = ffurl_alloc(&h, url, flags, NULL);
	if (ret < 0)
	return ret;

	if (h->prot->url_check) {
	ret = h->prot->url_check(h, flags);
	} else {
	ret = ffurl_connect(h, NULL);
	if (ret >= 0)
	ret = flags;
	}

	ffurl_close(h);
	return ret;
	}

	int avpriv_io_move(const char url_src, const char url_dst)
	{
	URLContext h_src, h_dst;
	int ret = ffurl_alloc(&h_src, url_src, AVIO_FLAG_READ_WRITE, NULL);
	if (ret < 0)
	return ret;
	ret = ffurl_alloc(&h_dst, url_dst, AVIO_FLAG_WRITE, NULL);
	if (ret < 0) {
	ffurl_close(h_src);
	return ret;
	}

	if (h_src->prot == h_dst->prot && h_src->prot->url_move)
	ret = h_src->prot->url_move(h_src, h_dst);
	else
	ret = AVERROR(ENOSYS);

	ffurl_close(h_src);
	ffurl_close(h_dst);
	return ret;
	}

	int avpriv_io_delete(const char *url)
	{
	URLContext *h;
	int ret = ffurl_alloc(&h, url, AVIO_FLAG_WRITE, NULL);
	if (ret < 0)
	return ret;

	if (h->prot->url_delete)
	ret = h->prot->url_delete(h);
	else
	ret = AVERROR(ENOSYS);

	ffurl_close(h);
	return ret;
	}

	int avio_open_dir(AVIODirContext *s, const char url, AVDictionary **options)
	{
	URLContext *h = NULL;
	AVIODirContext *ctx = NULL;
	int ret;
	av_assert0(s);

	ctx = av_mallocz(sizeof(*ctx));
	if (!ctx) {
	ret = AVERROR(ENOMEM);
	goto fail;
	}

	if ((ret = ffurl_alloc(&h, url, AVIO_FLAG_READ, NULL)) < 0)
	goto fail;

	if (h->prot->url_open_dir && h->prot->url_read_dir && h->prot->url_close_dir) {
	if (options && h->prot->priv_data_class &&
	(ret = av_opt_set_dict(h->priv_data, options)) < 0)
	goto fail;
	ret = h->prot->url_open_dir(h);
	} else
	ret = AVERROR(ENOSYS);
	if (ret < 0)
	goto fail;

	h->is_connected = 1;
	ctx->url_context = h;
	*s = ctx;
	return 0;

	fail:
	av_free(ctx);
	*s = NULL;
	ffurl_close(h);
	return ret;
	}

	int avio_read_dir(AVIODirContext s, AVIODirEntry *next)
	{
	URLContext *h;
	int ret;

	if (!s \|\| !s->url_context)
	return AVERROR(EINVAL);
	h = s->url_context;
	if ((ret = h->prot->url_read_dir(h, next)) < 0)
	avio_free_directory_entry(next);
	return ret;
	}

	int avio_close_dir(AVIODirContext **s)
	{
	URLContext *h;

	av_assert0(s);
	if (!(s) \|\| !(s)->url_context)
	return AVERROR(EINVAL);
	h = (*s)->url_context;
	h->prot->url_close_dir(h);
	ffurl_close(h);
	av_freep(s);
	*s = NULL;
	return 0;
	}

	void avio_free_directory_entry(AVIODirEntry **entry)
	{
	if (!entry \|\| !*entry)
	return;
	av_free((*entry)->name);
	av_freep(entry);
	}

	int64_t ffurl_size(URLContext *h)
	{
	int64_t pos, size;

	size = ffurl_seek(h, 0, AVSEEK_SIZE);
	if (size < 0) {
	pos = ffurl_seek(h, 0, SEEK_CUR);
	if ((size = ffurl_seek(h, -1, SEEK_END)) < 0)
	return size;
	size++;
	ffurl_seek(h, pos, SEEK_SET);
	}
	return size;
	}

	int ffurl_get_file_handle(URLContext *h)
	{
	if (!h \|\| !h->prot \|\| !h->prot->url_get_file_handle)
	return -1;
	return h->prot->url_get_file_handle(h);
	}

	int ffurl_get_multi_file_handle(URLContext h, int handles, int numhandles)
	{
	if (!h \|\| !h->prot)
	return AVERROR(ENOSYS);
	if (!h->prot->url_get_multi_file_handle) {
	if (!h->prot->url_get_file_handle)
	return AVERROR(ENOSYS);
	handles = av_malloc(sizeof(*handles));
	if (!*handles)
	return AVERROR(ENOMEM);
	*numhandles = 1;
	*handles[0] = h->prot->url_get_file_handle(h);
	return 0;
	}
	return h->prot->url_get_multi_file_handle(h, handles, numhandles);
	}

	int ffurl_get_short_seek(URLContext *h)
	{
	if (!h \|\| !h->prot \|\| !h->prot->url_get_short_seek)
	return AVERROR(ENOSYS);
	return h->prot->url_get_short_seek(h);
	}

	int ffurl_shutdown(URLContext *h, int flags)
	{
	if (!h \|\| !h->prot \|\| !h->prot->url_shutdown)
	return AVERROR(ENOSYS);
	return h->prot->url_shutdown(h, flags);
	}

	int ff_check_interrupt(AVIOInterruptCB *cb)
	{
	if (cb && cb->callback)
	return cb->callback(cb->opaque);
	return 0;
	}

	int ff_rename(const char url_src, const char url_dst, void *logctx)
	{
	int ret = avpriv_io_move(url_src, url_dst);
	if (ret < 0)
	av_log(logctx, AV_LOG_ERROR, "failed to rename file %s to %s: %s\n", url_src, url_dst, av_err2str(ret));
	return ret;
	}