xref: /third_party/ffmpeg/libavformat/avio.c (revision cabdff1a) 
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/opt.h"
25#include "libavutil/time.h"
26#include "libavutil/avassert.h"
27#include "os_support.h"
28#include "avformat.h"
29#include "internal.h"
30#if CONFIG_NETWORK
31#include "network.h"
32#endif
33#include "url.h"
34
35/** @name Logging context. */
36/*@{*/
37static const char *urlcontext_to_name(void *ptr)
38{
39    URLContext *h = (URLContext *)ptr;
40    if (h->prot)
41        return h->prot->name;
42    else
43        return "NULL";
44}
45
46static void *urlcontext_child_next(void *obj, void *prev)
47{
48    URLContext *h = obj;
49    if (!prev && h->priv_data && h->prot->priv_data_class)
50        return h->priv_data;
51    return NULL;
52}
53
54#define OFFSET(x) offsetof(URLContext,x)
55#define E AV_OPT_FLAG_ENCODING_PARAM
56#define D AV_OPT_FLAG_DECODING_PARAM
57static const AVOption options[] = {
58    {"protocol_whitelist", "List of protocols that are allowed to be used", OFFSET(protocol_whitelist), AV_OPT_TYPE_STRING, { .str = NULL },  0, 0, D },
59    {"protocol_blacklist", "List of protocols that are not allowed to be used", OFFSET(protocol_blacklist), AV_OPT_TYPE_STRING, { .str = NULL },  0, 0, D },
60    {"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 },
61    { NULL }
62};
63
64const AVClass ffurl_context_class = {
65    .class_name       = "URLContext",
66    .item_name        = urlcontext_to_name,
67    .option           = options,
68    .version          = LIBAVUTIL_VERSION_INT,
69    .child_next       = urlcontext_child_next,
70    .child_class_iterate = ff_urlcontext_child_class_iterate,
71};
72/*@}*/
73
74static int url_alloc_for_protocol(URLContext **puc, const URLProtocol *up,
75                                  const char *filename, int flags,
76                                  const AVIOInterruptCB *int_cb)
77{
78    URLContext *uc;
79    int err;
80
81#if CONFIG_NETWORK
82    if (up->flags & URL_PROTOCOL_FLAG_NETWORK && !ff_network_init())
83        return AVERROR(EIO);
84#endif
85    if ((flags & AVIO_FLAG_READ) && !up->url_read) {
86        av_log(NULL, AV_LOG_ERROR,
87               "Impossible to open the '%s' protocol for reading\n", up->name);
88        return AVERROR(EIO);
89    }
90    if ((flags & AVIO_FLAG_WRITE) && !up->url_write) {
91        av_log(NULL, AV_LOG_ERROR,
92               "Impossible to open the '%s' protocol for writing\n", up->name);
93        return AVERROR(EIO);
94    }
95    uc = av_mallocz(sizeof(URLContext) + strlen(filename) + 1);
96    if (!uc) {
97        err = AVERROR(ENOMEM);
98        goto fail;
99    }
100    uc->av_class = &ffurl_context_class;
101    uc->filename = (char *)&uc[1];
102    strcpy(uc->filename, filename);
103    uc->prot            = up;
104    uc->flags           = flags;
105    uc->is_streamed     = 0; /* default = not streamed */
106    uc->max_packet_size = 0; /* default: stream file */
107    if (up->priv_data_size) {
108        uc->priv_data = av_mallocz(up->priv_data_size);
109        if (!uc->priv_data) {
110            err = AVERROR(ENOMEM);
111            goto fail;
112        }
113        if (up->priv_data_class) {
114            char *start;
115            *(const AVClass **)uc->priv_data = up->priv_data_class;
116            av_opt_set_defaults(uc->priv_data);
117            if (av_strstart(uc->filename, up->name, (const char**)&start) && *start == ',') {
118                int ret= 0;
119                char *p= start;
120                char sep= *++p;
121                char *key, *val;
122                p++;
123
124                if (strcmp(up->name, "subfile"))
125                    ret = AVERROR(EINVAL);
126
127                while(ret >= 0 && (key= strchr(p, sep)) && p<key && (val = strchr(key+1, sep))){
128                    *val= *key= 0;
129                    if (strcmp(p, "start") && strcmp(p, "end")) {
130                        ret = AVERROR_OPTION_NOT_FOUND;
131                    } else
132                        ret= av_opt_set(uc->priv_data, p, key+1, 0);
133                    if (ret == AVERROR_OPTION_NOT_FOUND)
134                        av_log(uc, AV_LOG_ERROR, "Key '%s' not found.\n", p);
135                    *val= *key= sep;
136                    p= val+1;
137                }
138                if(ret<0 || p!=key){
139                    av_log(uc, AV_LOG_ERROR, "Error parsing options string %s\n", start);
140                    av_freep(&uc->priv_data);
141                    av_freep(&uc);
142                    err = AVERROR(EINVAL);
143                    goto fail;
144                }
145                memmove(start, key+1, strlen(key));
146            }
147        }
148    }
149    if (int_cb)
150        uc->interrupt_callback = *int_cb;
151
152    *puc = uc;
153    return 0;
154fail:
155    *puc = NULL;
156    if (uc)
157        av_freep(&uc->priv_data);
158    av_freep(&uc);
159#if CONFIG_NETWORK
160    if (up->flags & URL_PROTOCOL_FLAG_NETWORK)
161        ff_network_close();
162#endif
163    return err;
164}
165
166int ffurl_connect(URLContext *uc, AVDictionary **options)
167{
168    int err;
169    AVDictionary *tmp_opts = NULL;
170    AVDictionaryEntry *e;
171
172    if (!options)
173        options = &tmp_opts;
174
175    // Check that URLContext was initialized correctly and lists are matching if set
176    av_assert0(!(e=av_dict_get(*options, "protocol_whitelist", NULL, 0)) ||
177               (uc->protocol_whitelist && !strcmp(uc->protocol_whitelist, e->value)));
178    av_assert0(!(e=av_dict_get(*options, "protocol_blacklist", NULL, 0)) ||
179               (uc->protocol_blacklist && !strcmp(uc->protocol_blacklist, e->value)));
180
181    if (uc->protocol_whitelist && av_match_list(uc->prot->name, uc->protocol_whitelist, ',') <= 0) {
182        av_log(uc, AV_LOG_ERROR, "Protocol '%s' not on whitelist '%s'!\n", uc->prot->name, uc->protocol_whitelist);
183        return AVERROR(EINVAL);
184    }
185
186    if (uc->protocol_blacklist && av_match_list(uc->prot->name, uc->protocol_blacklist, ',') > 0) {
187        av_log(uc, AV_LOG_ERROR, "Protocol '%s' on blacklist '%s'!\n", uc->prot->name, uc->protocol_blacklist);
188        return AVERROR(EINVAL);
189    }
190
191    if (!uc->protocol_whitelist && uc->prot->default_whitelist) {
192        av_log(uc, AV_LOG_DEBUG, "Setting default whitelist '%s'\n", uc->prot->default_whitelist);
193        uc->protocol_whitelist = av_strdup(uc->prot->default_whitelist);
194        if (!uc->protocol_whitelist) {
195            return AVERROR(ENOMEM);
196        }
197    } else if (!uc->protocol_whitelist)
198        av_log(uc, AV_LOG_DEBUG, "No default whitelist set\n"); // This should be an error once all declare a default whitelist
199
200    if ((err = av_dict_set(options, "protocol_whitelist", uc->protocol_whitelist, 0)) < 0)
201        return err;
202    if ((err = av_dict_set(options, "protocol_blacklist", uc->protocol_blacklist, 0)) < 0)
203        return err;
204
205    err =
206        uc->prot->url_open2 ? uc->prot->url_open2(uc,
207                                                  uc->filename,
208                                                  uc->flags,
209                                                  options) :
210        uc->prot->url_open(uc, uc->filename, uc->flags);
211
212    av_dict_set(options, "protocol_whitelist", NULL, 0);
213    av_dict_set(options, "protocol_blacklist", NULL, 0);
214
215    if (err)
216        return err;
217    uc->is_connected = 1;
218    /* We must be careful here as ffurl_seek() could be slow,
219     * for example for http */
220    if ((uc->flags & AVIO_FLAG_WRITE) || !strcmp(uc->prot->name, "file"))
221        if (!uc->is_streamed && ffurl_seek(uc, 0, SEEK_SET) < 0)
222            uc->is_streamed = 1;
223    return 0;
224}
225
226int ffurl_accept(URLContext *s, URLContext **c)
227{
228    av_assert0(!*c);
229    if (s->prot->url_accept)
230        return s->prot->url_accept(s, c);
231    return AVERROR(EBADF);
232}
233
234int ffurl_handshake(URLContext *c)
235{
236    int ret;
237    if (c->prot->url_handshake) {
238        ret = c->prot->url_handshake(c);
239        if (ret)
240            return ret;
241    }
242    c->is_connected = 1;
243    return 0;
244}
245
246#define URL_SCHEME_CHARS                        \
247    "abcdefghijklmnopqrstuvwxyz"                \
248    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"                \
249    "0123456789+-."
250
251static const struct URLProtocol *url_find_protocol(const char *filename)
252{
253    const URLProtocol **protocols;
254    char proto_str[128], proto_nested[128], *ptr;
255    size_t proto_len = strspn(filename, URL_SCHEME_CHARS);
256    int i;
257
258    if (filename[proto_len] != ':' &&
259        (strncmp(filename, "subfile,", 8) || !strchr(filename + proto_len + 1, ':')) ||
260        is_dos_path(filename))
261        strcpy(proto_str, "file");
262    else
263        av_strlcpy(proto_str, filename,
264                   FFMIN(proto_len + 1, sizeof(proto_str)));
265
266    av_strlcpy(proto_nested, proto_str, sizeof(proto_nested));
267    if ((ptr = strchr(proto_nested, '+')))
268        *ptr = '\0';
269
270    protocols = ffurl_get_protocols(NULL, NULL);
271    if (!protocols)
272        return NULL;
273    for (i = 0; protocols[i]; i++) {
274            const URLProtocol *up = protocols[i];
275        if (!strcmp(proto_str, up->name)) {
276            av_freep(&protocols);
277            return up;
278        }
279        if (up->flags & URL_PROTOCOL_FLAG_NESTED_SCHEME &&
280            !strcmp(proto_nested, up->name)) {
281            av_freep(&protocols);
282            return up;
283        }
284    }
285    av_freep(&protocols);
286    if (av_strstart(filename, "https:", NULL) || av_strstart(filename, "tls:", NULL))
287        av_log(NULL, AV_LOG_WARNING, "https protocol not found, recompile FFmpeg with "
288                                     "openssl, gnutls or securetransport enabled.\n");
289
290    return NULL;
291}
292
293int ffurl_alloc(URLContext **puc, const char *filename, int flags,
294                const AVIOInterruptCB *int_cb)
295{
296    const URLProtocol *p = NULL;
297
298    p = url_find_protocol(filename);
299    if (p)
300       return url_alloc_for_protocol(puc, p, filename, flags, int_cb);
301
302    *puc = NULL;
303    return AVERROR_PROTOCOL_NOT_FOUND;
304}
305
306int ffurl_open_whitelist(URLContext **puc, const char *filename, int flags,
307                         const AVIOInterruptCB *int_cb, AVDictionary **options,
308                         const char *whitelist, const char* blacklist,
309                         URLContext *parent)
310{
311    AVDictionary *tmp_opts = NULL;
312    AVDictionaryEntry *e;
313    int ret = ffurl_alloc(puc, filename, flags, int_cb);
314    if (ret < 0)
315        return ret;
316    if (parent) {
317        ret = av_opt_copy(*puc, parent);
318        if (ret < 0)
319            goto fail;
320    }
321    if (options &&
322        (ret = av_opt_set_dict(*puc, options)) < 0)
323        goto fail;
324    if (options && (*puc)->prot->priv_data_class &&
325        (ret = av_opt_set_dict((*puc)->priv_data, options)) < 0)
326        goto fail;
327
328    if (!options)
329        options = &tmp_opts;
330
331    av_assert0(!whitelist ||
332               !(e=av_dict_get(*options, "protocol_whitelist", NULL, 0)) ||
333               !strcmp(whitelist, e->value));
334    av_assert0(!blacklist ||
335               !(e=av_dict_get(*options, "protocol_blacklist", NULL, 0)) ||
336               !strcmp(blacklist, e->value));
337
338    if ((ret = av_dict_set(options, "protocol_whitelist", whitelist, 0)) < 0)
339        goto fail;
340
341    if ((ret = av_dict_set(options, "protocol_blacklist", blacklist, 0)) < 0)
342        goto fail;
343
344    if ((ret = av_opt_set_dict(*puc, options)) < 0)
345        goto fail;
346
347    ret = ffurl_connect(*puc, options);
348
349    if (!ret)
350        return 0;
351fail:
352    ffurl_closep(puc);
353    return ret;
354}
355
356static inline int retry_transfer_wrapper(URLContext *h, uint8_t *buf,
357                                         int size, int size_min,
358                                         int (*transfer_func)(URLContext *h,
359                                                              uint8_t *buf,
360                                                              int size))
361{
362    int ret, len;
363    int fast_retries = 5;
364    int64_t wait_since = 0;
365
366    len = 0;
367    while (len < size_min) {
368        if (ff_check_interrupt(&h->interrupt_callback))
369            return AVERROR_EXIT;
370        ret = transfer_func(h, buf + len, size - len);
371        if (ret == AVERROR(EINTR))
372            continue;
373        if (h->flags & AVIO_FLAG_NONBLOCK)
374            return ret;
375        if (ret == AVERROR(EAGAIN)) {
376            ret = 0;
377            if (fast_retries) {
378                fast_retries--;
379            } else {
380                if (h->rw_timeout) {
381                    if (!wait_since)
382                        wait_since = av_gettime_relative();
383                    else if (av_gettime_relative() > wait_since + h->rw_timeout)
384                        return AVERROR(EIO);
385                }
386                av_usleep(1000);
387            }
388        } else if (ret == AVERROR_EOF)
389            return (len > 0) ? len : AVERROR_EOF;
390        else if (ret < 0)
391            return ret;
392        if (ret) {
393            fast_retries = FFMAX(fast_retries, 2);
394            wait_since = 0;
395        }
396        len += ret;
397    }
398    return len;
399}
400
401int ffurl_read(URLContext *h, unsigned char *buf, int size)
402{
403    if (!(h->flags & AVIO_FLAG_READ))
404        return AVERROR(EIO);
405    return retry_transfer_wrapper(h, buf, size, 1, h->prot->url_read);
406}
407
408int ffurl_read_complete(URLContext *h, unsigned char *buf, int size)
409{
410    if (!(h->flags & AVIO_FLAG_READ))
411        return AVERROR(EIO);
412    return retry_transfer_wrapper(h, buf, size, size, h->prot->url_read);
413}
414
415int ffurl_write(URLContext *h, const unsigned char *buf, int size)
416{
417    if (!(h->flags & AVIO_FLAG_WRITE))
418        return AVERROR(EIO);
419    /* avoid sending too big packets */
420    if (h->max_packet_size && size > h->max_packet_size)
421        return AVERROR(EIO);
422
423    return retry_transfer_wrapper(h, (unsigned char *)buf, size, size,
424                                  (int (*)(struct URLContext *, uint8_t *, int))
425                                  h->prot->url_write);
426}
427
428int64_t ffurl_seek(URLContext *h, int64_t pos, int whence)
429{
430    int64_t ret;
431
432    if (!h->prot->url_seek)
433        return AVERROR(ENOSYS);
434    ret = h->prot->url_seek(h, pos, whence & ~AVSEEK_FORCE);
435    return ret;
436}
437
438int ffurl_closep(URLContext **hh)
439{
440    URLContext *h= *hh;
441    int ret = 0;
442    if (!h)
443        return 0;     /* can happen when ffurl_open fails */
444
445    if (h->is_connected && h->prot->url_close)
446        ret = h->prot->url_close(h);
447#if CONFIG_NETWORK
448    if (h->prot->flags & URL_PROTOCOL_FLAG_NETWORK)
449        ff_network_close();
450#endif
451    if (h->prot->priv_data_size) {
452        if (h->prot->priv_data_class)
453            av_opt_free(h->priv_data);
454        av_freep(&h->priv_data);
455    }
456    av_opt_free(h);
457    av_freep(hh);
458    return ret;
459}
460
461int ffurl_close(URLContext *h)
462{
463    return ffurl_closep(&h);
464}
465
466
467const char *avio_find_protocol_name(const char *url)
468{
469    const URLProtocol *p = url_find_protocol(url);
470
471    return p ? p->name : NULL;
472}
473
474int avio_check(const char *url, int flags)
475{
476    URLContext *h;
477    int ret = ffurl_alloc(&h, url, flags, NULL);
478    if (ret < 0)
479        return ret;
480
481    if (h->prot->url_check) {
482        ret = h->prot->url_check(h, flags);
483    } else {
484        ret = ffurl_connect(h, NULL);
485        if (ret >= 0)
486            ret = flags;
487    }
488
489    ffurl_close(h);
490    return ret;
491}
492
493int ffurl_move(const char *url_src, const char *url_dst)
494{
495    URLContext *h_src, *h_dst;
496    int ret = ffurl_alloc(&h_src, url_src, AVIO_FLAG_READ_WRITE, NULL);
497    if (ret < 0)
498        return ret;
499    ret = ffurl_alloc(&h_dst, url_dst, AVIO_FLAG_WRITE, NULL);
500    if (ret < 0) {
501        ffurl_close(h_src);
502        return ret;
503    }
504
505    if (h_src->prot == h_dst->prot && h_src->prot->url_move)
506        ret = h_src->prot->url_move(h_src, h_dst);
507    else
508        ret = AVERROR(ENOSYS);
509
510    ffurl_close(h_src);
511    ffurl_close(h_dst);
512    return ret;
513}
514
515int ffurl_delete(const char *url)
516{
517    URLContext *h;
518    int ret = ffurl_alloc(&h, url, AVIO_FLAG_WRITE, NULL);
519    if (ret < 0)
520        return ret;
521
522    if (h->prot->url_delete)
523        ret = h->prot->url_delete(h);
524    else
525        ret = AVERROR(ENOSYS);
526
527    ffurl_close(h);
528    return ret;
529}
530
531int avio_open_dir(AVIODirContext **s, const char *url, AVDictionary **options)
532{
533    URLContext *h = NULL;
534    AVIODirContext *ctx = NULL;
535    int ret;
536    av_assert0(s);
537
538    ctx = av_mallocz(sizeof(*ctx));
539    if (!ctx) {
540        ret = AVERROR(ENOMEM);
541        goto fail;
542    }
543
544    if ((ret = ffurl_alloc(&h, url, AVIO_FLAG_READ, NULL)) < 0)
545        goto fail;
546
547    if (h->prot->url_open_dir && h->prot->url_read_dir && h->prot->url_close_dir) {
548        if (options && h->prot->priv_data_class &&
549            (ret = av_opt_set_dict(h->priv_data, options)) < 0)
550            goto fail;
551        ret = h->prot->url_open_dir(h);
552    } else
553        ret = AVERROR(ENOSYS);
554    if (ret < 0)
555        goto fail;
556
557    h->is_connected = 1;
558    ctx->url_context = h;
559    *s = ctx;
560    return 0;
561
562  fail:
563    av_free(ctx);
564    *s = NULL;
565    ffurl_close(h);
566    return ret;
567}
568
569int avio_read_dir(AVIODirContext *s, AVIODirEntry **next)
570{
571    URLContext *h;
572    int ret;
573
574    if (!s || !s->url_context)
575        return AVERROR(EINVAL);
576    h = s->url_context;
577    if ((ret = h->prot->url_read_dir(h, next)) < 0)
578        avio_free_directory_entry(next);
579    return ret;
580}
581
582int avio_close_dir(AVIODirContext **s)
583{
584    URLContext *h;
585
586    av_assert0(s);
587    if (!(*s) || !(*s)->url_context)
588        return AVERROR(EINVAL);
589    h = (*s)->url_context;
590    h->prot->url_close_dir(h);
591    ffurl_close(h);
592    av_freep(s);
593    *s = NULL;
594    return 0;
595}
596
597void avio_free_directory_entry(AVIODirEntry **entry)
598{
599    if (!entry || !*entry)
600        return;
601    av_free((*entry)->name);
602    av_freep(entry);
603}
604
605int64_t ffurl_size(URLContext *h)
606{
607    int64_t pos, size;
608
609    size = ffurl_seek(h, 0, AVSEEK_SIZE);
610    if (size < 0) {
611        pos = ffurl_seek(h, 0, SEEK_CUR);
612        if ((size = ffurl_seek(h, -1, SEEK_END)) < 0)
613            return size;
614        size++;
615        ffurl_seek(h, pos, SEEK_SET);
616    }
617    return size;
618}
619
620int ffurl_get_file_handle(URLContext *h)
621{
622    if (!h || !h->prot || !h->prot->url_get_file_handle)
623        return -1;
624    return h->prot->url_get_file_handle(h);
625}
626
627int ffurl_get_multi_file_handle(URLContext *h, int **handles, int *numhandles)
628{
629    if (!h || !h->prot)
630        return AVERROR(ENOSYS);
631    if (!h->prot->url_get_multi_file_handle) {
632        if (!h->prot->url_get_file_handle)
633            return AVERROR(ENOSYS);
634        *handles = av_malloc(sizeof(**handles));
635        if (!*handles)
636            return AVERROR(ENOMEM);
637        *numhandles = 1;
638        *handles[0] = h->prot->url_get_file_handle(h);
639        return 0;
640    }
641    return h->prot->url_get_multi_file_handle(h, handles, numhandles);
642}
643
644int ffurl_get_short_seek(URLContext *h)
645{
646    if (!h || !h->prot || !h->prot->url_get_short_seek)
647        return AVERROR(ENOSYS);
648    return h->prot->url_get_short_seek(h);
649}
650
651int ffurl_shutdown(URLContext *h, int flags)
652{
653    if (!h || !h->prot || !h->prot->url_shutdown)
654        return AVERROR(ENOSYS);
655    return h->prot->url_shutdown(h, flags);
656}
657
658int ff_check_interrupt(AVIOInterruptCB *cb)
659{
660    if (cb && cb->callback)
661        return cb->callback(cb->opaque);
662    return 0;
663}
664
665int ff_rename(const char *url_src, const char *url_dst, void *logctx)
666{
667    int ret = ffurl_move(url_src, url_dst);
668    if (ret < 0)
669        av_log(logctx, AV_LOG_ERROR, "failed to rename file %s to %s: %s\n", url_src, url_dst, av_err2str(ret));
670    return ret;
671}
672