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1 /*
2 * QEMU Block driver for CURL images
3 *
4 * Copyright (c) 2009 Alexander Graf <agraf@suse.de>
5 *
6 * Permission is hereby granted, free of charge, to any person obtaining a copy
7 * of this software and associated documentation files (the "Software"), to deal
8 * in the Software without restriction, including without limitation the rights
9 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10 * copies of the Software, and to permit persons to whom the Software is
11 * furnished to do so, subject to the following conditions:
12 *
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
15 *
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22 * THE SOFTWARE.
23 */
24 #include "qemu-common.h"
25 #include "block/block_int.h"
26 #include <curl/curl.h>
27
28 // #define DEBUG
29 // #define DEBUG_VERBOSE
30
31 #ifdef DEBUG_CURL
32 #define DPRINTF(fmt, ...) do { printf(fmt, ## __VA_ARGS__); } while (0)
33 #else
34 #define DPRINTF(fmt, ...) do { } while (0)
35 #endif
36
37 #if LIBCURL_VERSION_NUM >= 0x071000
38 /* The multi interface timer callback was introduced in 7.16.0 */
39 #define NEED_CURL_TIMER_CALLBACK
40 #endif
41
42 #define PROTOCOLS (CURLPROTO_HTTP | CURLPROTO_HTTPS | \
43 CURLPROTO_FTP | CURLPROTO_FTPS | \
44 CURLPROTO_TFTP)
45
46 #define CURL_NUM_STATES 8
47 #define CURL_NUM_ACB 8
48 #define SECTOR_SIZE 512
49 #define READ_AHEAD_SIZE (256 * 1024)
50
51 #define FIND_RET_NONE 0
52 #define FIND_RET_OK 1
53 #define FIND_RET_WAIT 2
54
55 struct BDRVCURLState;
56
57 typedef struct CURLAIOCB {
58 BlockDriverAIOCB common;
59 QEMUBH *bh;
60 QEMUIOVector *qiov;
61
62 int64_t sector_num;
63 int nb_sectors;
64
65 size_t start;
66 size_t end;
67 } CURLAIOCB;
68
69 typedef struct CURLState
70 {
71 struct BDRVCURLState *s;
72 CURLAIOCB *acb[CURL_NUM_ACB];
73 CURL *curl;
74 char *orig_buf;
75 size_t buf_start;
76 size_t buf_off;
77 size_t buf_len;
78 char range[128];
79 char errmsg[CURL_ERROR_SIZE];
80 char in_use;
81 } CURLState;
82
83 typedef struct BDRVCURLState {
84 CURLM *multi;
85 QEMUTimer timer;
86 size_t len;
87 CURLState states[CURL_NUM_STATES];
88 char *url;
89 size_t readahead_size;
90 bool accept_range;
91 } BDRVCURLState;
92
93 static void curl_clean_state(CURLState *s);
94 static void curl_multi_do(void *arg);
95
96 #ifdef NEED_CURL_TIMER_CALLBACK
97 static int curl_timer_cb(CURLM *multi, long timeout_ms, void *opaque)
98 {
99 BDRVCURLState *s = opaque;
100
101 DPRINTF("CURL: timer callback timeout_ms %ld\n", timeout_ms);
102 if (timeout_ms == -1) {
103 timer_del(&s->timer);
104 } else {
105 int64_t timeout_ns = (int64_t)timeout_ms * 1000 * 1000;
106 timer_mod(&s->timer,
107 qemu_clock_get_ns(QEMU_CLOCK_REALTIME) + timeout_ns);
108 }
109 return 0;
110 }
111 #endif
112
113 static int curl_sock_cb(CURL *curl, curl_socket_t fd, int action,
114 void *s, void *sp)
115 {
116 DPRINTF("CURL (AIO): Sock action %d on fd %d\n", action, fd);
117 switch (action) {
118 case CURL_POLL_IN:
119 qemu_aio_set_fd_handler(fd, curl_multi_do, NULL, s);
120 break;
121 case CURL_POLL_OUT:
122 qemu_aio_set_fd_handler(fd, NULL, curl_multi_do, s);
123 break;
124 case CURL_POLL_INOUT:
125 qemu_aio_set_fd_handler(fd, curl_multi_do, curl_multi_do, s);
126 break;
127 case CURL_POLL_REMOVE:
128 qemu_aio_set_fd_handler(fd, NULL, NULL, NULL);
129 break;
130 }
131
132 return 0;
133 }
134
135 static size_t curl_header_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
136 {
137 BDRVCURLState *s = opaque;
138 size_t realsize = size * nmemb;
139 const char *accept_line = "Accept-Ranges: bytes";
140
141 if (realsize >= strlen(accept_line)
142 && strncmp((char *)ptr, accept_line, strlen(accept_line)) == 0) {
143 s->accept_range = true;
144 }
145
146 return realsize;
147 }
148
149 static size_t curl_read_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
150 {
151 CURLState *s = ((CURLState*)opaque);
152 size_t realsize = size * nmemb;
153 int i;
154
155 DPRINTF("CURL: Just reading %zd bytes\n", realsize);
156
157 if (!s || !s->orig_buf)
158 goto read_end;
159
160 if (s->buf_off >= s->buf_len) {
161 /* buffer full, read nothing */
162 return 0;
163 }
164 realsize = MIN(realsize, s->buf_len - s->buf_off);
165 memcpy(s->orig_buf + s->buf_off, ptr, realsize);
166 s->buf_off += realsize;
167
168 for(i=0; i<CURL_NUM_ACB; i++) {
169 CURLAIOCB *acb = s->acb[i];
170
171 if (!acb)
172 continue;
173
174 if ((s->buf_off >= acb->end)) {
175 qemu_iovec_from_buf(acb->qiov, 0, s->orig_buf + acb->start,
176 acb->end - acb->start);
177 acb->common.cb(acb->common.opaque, 0);
178 qemu_aio_release(acb);
179 s->acb[i] = NULL;
180 }
181 }
182
183 read_end:
184 return realsize;
185 }
186
187 static int curl_find_buf(BDRVCURLState *s, size_t start, size_t len,
188 CURLAIOCB *acb)
189 {
190 int i;
191 size_t end = start + len;
192
193 for (i=0; i<CURL_NUM_STATES; i++) {
194 CURLState *state = &s->states[i];
195 size_t buf_end = (state->buf_start + state->buf_off);
196 size_t buf_fend = (state->buf_start + state->buf_len);
197
198 if (!state->orig_buf)
199 continue;
200 if (!state->buf_off)
201 continue;
202
203 // Does the existing buffer cover our section?
204 if ((start >= state->buf_start) &&
205 (start <= buf_end) &&
206 (end >= state->buf_start) &&
207 (end <= buf_end))
208 {
209 char *buf = state->orig_buf + (start - state->buf_start);
210
211 qemu_iovec_from_buf(acb->qiov, 0, buf, len);
212 acb->common.cb(acb->common.opaque, 0);
213
214 return FIND_RET_OK;
215 }
216
217 // Wait for unfinished chunks
218 if ((start >= state->buf_start) &&
219 (start <= buf_fend) &&
220 (end >= state->buf_start) &&
221 (end <= buf_fend))
222 {
223 int j;
224
225 acb->start = start - state->buf_start;
226 acb->end = acb->start + len;
227
228 for (j=0; j<CURL_NUM_ACB; j++) {
229 if (!state->acb[j]) {
230 state->acb[j] = acb;
231 return FIND_RET_WAIT;
232 }
233 }
234 }
235 }
236
237 return FIND_RET_NONE;
238 }
239
240 static void curl_multi_read(BDRVCURLState *s)
241 {
242 int msgs_in_queue;
243
244 /* Try to find done transfers, so we can free the easy
245 * handle again. */
246 do {
247 CURLMsg *msg;
248 msg = curl_multi_info_read(s->multi, &msgs_in_queue);
249
250 if (!msg)
251 break;
252 if (msg->msg == CURLMSG_NONE)
253 break;
254
255 switch (msg->msg) {
256 case CURLMSG_DONE:
257 {
258 CURLState *state = NULL;
259 curl_easy_getinfo(msg->easy_handle, CURLINFO_PRIVATE,
260 (char **)&state);
261
262 /* ACBs for successful messages get completed in curl_read_cb */
263 if (msg->data.result != CURLE_OK) {
264 int i;
265 for (i = 0; i < CURL_NUM_ACB; i++) {
266 CURLAIOCB *acb = state->acb[i];
267
268 if (acb == NULL) {
269 continue;
270 }
271
272 acb->common.cb(acb->common.opaque, -EIO);
273 qemu_aio_release(acb);
274 state->acb[i] = NULL;
275 }
276 }
277
278 curl_clean_state(state);
279 break;
280 }
281 default:
282 msgs_in_queue = 0;
283 break;
284 }
285 } while(msgs_in_queue);
286 }
287
288 static void curl_multi_do(void *arg)
289 {
290 BDRVCURLState *s = (BDRVCURLState *)arg;
291 int running;
292 int r;
293
294 if (!s->multi) {
295 return;
296 }
297
298 do {
299 r = curl_multi_socket_all(s->multi, &running);
300 } while(r == CURLM_CALL_MULTI_PERFORM);
301
302 curl_multi_read(s);
303 }
304
305 static void curl_multi_timeout_do(void *arg)
306 {
307 #ifdef NEED_CURL_TIMER_CALLBACK
308 BDRVCURLState *s = (BDRVCURLState *)arg;
309 int running;
310
311 if (!s->multi) {
312 return;
313 }
314
315 curl_multi_socket_action(s->multi, CURL_SOCKET_TIMEOUT, 0, &running);
316
317 curl_multi_read(s);
318 #else
319 abort();
320 #endif
321 }
322
323 static CURLState *curl_init_state(BDRVCURLState *s)
324 {
325 CURLState *state = NULL;
326 int i, j;
327
328 do {
329 for (i=0; i<CURL_NUM_STATES; i++) {
330 for (j=0; j<CURL_NUM_ACB; j++)
331 if (s->states[i].acb[j])
332 continue;
333 if (s->states[i].in_use)
334 continue;
335
336 state = &s->states[i];
337 state->in_use = 1;
338 break;
339 }
340 if (!state) {
341 g_usleep(100);
342 curl_multi_do(s);
343 }
344 } while(!state);
345
346 if (state->curl)
347 goto has_curl;
348
349 state->curl = curl_easy_init();
350 if (!state->curl)
351 return NULL;
352 curl_easy_setopt(state->curl, CURLOPT_URL, s->url);
353 curl_easy_setopt(state->curl, CURLOPT_TIMEOUT, 5);
354 curl_easy_setopt(state->curl, CURLOPT_WRITEFUNCTION, (void *)curl_read_cb);
355 curl_easy_setopt(state->curl, CURLOPT_WRITEDATA, (void *)state);
356 curl_easy_setopt(state->curl, CURLOPT_PRIVATE, (void *)state);
357 curl_easy_setopt(state->curl, CURLOPT_AUTOREFERER, 1);
358 curl_easy_setopt(state->curl, CURLOPT_FOLLOWLOCATION, 1);
359 curl_easy_setopt(state->curl, CURLOPT_NOSIGNAL, 1);
360 curl_easy_setopt(state->curl, CURLOPT_ERRORBUFFER, state->errmsg);
361 curl_easy_setopt(state->curl, CURLOPT_FAILONERROR, 1);
362
363 /* Restrict supported protocols to avoid security issues in the more
364 * obscure protocols. For example, do not allow POP3/SMTP/IMAP see
365 * CVE-2013-0249.
366 *
367 * Restricting protocols is only supported from 7.19.4 upwards.
368 */
369 #if LIBCURL_VERSION_NUM >= 0x071304
370 curl_easy_setopt(state->curl, CURLOPT_PROTOCOLS, PROTOCOLS);
371 curl_easy_setopt(state->curl, CURLOPT_REDIR_PROTOCOLS, PROTOCOLS);
372 #endif
373
374 #ifdef DEBUG_VERBOSE
375 curl_easy_setopt(state->curl, CURLOPT_VERBOSE, 1);
376 #endif
377
378 has_curl:
379
380 state->s = s;
381
382 return state;
383 }
384
385 static void curl_clean_state(CURLState *s)
386 {
387 if (s->s->multi)
388 curl_multi_remove_handle(s->s->multi, s->curl);
389 s->in_use = 0;
390 }
391
392 static void curl_parse_filename(const char *filename, QDict *options,
393 Error **errp)
394 {
395
396 #define RA_OPTSTR ":readahead="
397 char *file;
398 char *ra;
399 const char *ra_val;
400 int parse_state = 0;
401
402 file = g_strdup(filename);
403
404 /* Parse a trailing ":readahead=#:" param, if present. */
405 ra = file + strlen(file) - 1;
406 while (ra >= file) {
407 if (parse_state == 0) {
408 if (*ra == ':') {
409 parse_state++;
410 } else {
411 break;
412 }
413 } else if (parse_state == 1) {
414 if (*ra > '9' || *ra < '0') {
415 char *opt_start = ra - strlen(RA_OPTSTR) + 1;
416 if (opt_start > file &&
417 strncmp(opt_start, RA_OPTSTR, strlen(RA_OPTSTR)) == 0) {
418 ra_val = ra + 1;
419 ra -= strlen(RA_OPTSTR) - 1;
420 *ra = '\0';
421 qdict_put(options, "readahead", qstring_from_str(ra_val));
422 }
423 break;
424 }
425 }
426 ra--;
427 }
428
429 qdict_put(options, "url", qstring_from_str(file));
430
431 g_free(file);
432 }
433
434 static QemuOptsList runtime_opts = {
435 .name = "curl",
436 .head = QTAILQ_HEAD_INITIALIZER(runtime_opts.head),
437 .desc = {
438 {
439 .name = "url",
440 .type = QEMU_OPT_STRING,
441 .help = "URL to open",
442 },
443 {
444 .name = "readahead",
445 .type = QEMU_OPT_SIZE,
446 .help = "Readahead size",
447 },
448 { /* end of list */ }
449 },
450 };
451
452 static int curl_open(BlockDriverState *bs, QDict *options, int flags,
453 Error **errp)
454 {
455 BDRVCURLState *s = bs->opaque;
456 CURLState *state = NULL;
457 QemuOpts *opts;
458 Error *local_err = NULL;
459 const char *file;
460 double d;
461
462 static int inited = 0;
463
464 if (flags & BDRV_O_RDWR) {
465 error_setg(errp, "curl block device does not support writes");
466 return -EROFS;
467 }
468
469 opts = qemu_opts_create(&runtime_opts, NULL, 0, &error_abort);
470 qemu_opts_absorb_qdict(opts, options, &local_err);
471 if (local_err) {
472 error_propagate(errp, local_err);
473 goto out_noclean;
474 }
475
476 s->readahead_size = qemu_opt_get_size(opts, "readahead", READ_AHEAD_SIZE);
477 if ((s->readahead_size & 0x1ff) != 0) {
478 error_setg(errp, "HTTP_READAHEAD_SIZE %zd is not a multiple of 512",
479 s->readahead_size);
480 goto out_noclean;
481 }
482
483 file = qemu_opt_get(opts, "url");
484 if (file == NULL) {
485 error_setg(errp, "curl block driver requires an 'url' option");
486 goto out_noclean;
487 }
488
489 if (!inited) {
490 curl_global_init(CURL_GLOBAL_ALL);
491 inited = 1;
492 }
493
494 DPRINTF("CURL: Opening %s\n", file);
495 s->url = g_strdup(file);
496 state = curl_init_state(s);
497 if (!state)
498 goto out_noclean;
499
500 // Get file size
501
502 s->accept_range = false;
503 curl_easy_setopt(state->curl, CURLOPT_NOBODY, 1);
504 curl_easy_setopt(state->curl, CURLOPT_HEADERFUNCTION,
505 curl_header_cb);
506 curl_easy_setopt(state->curl, CURLOPT_HEADERDATA, s);
507 if (curl_easy_perform(state->curl))
508 goto out;
509 curl_easy_getinfo(state->curl, CURLINFO_CONTENT_LENGTH_DOWNLOAD, &d);
510 if (d)
511 s->len = (size_t)d;
512 else if(!s->len)
513 goto out;
514 if ((!strncasecmp(s->url, "http://", strlen("http://"))
515 || !strncasecmp(s->url, "https://", strlen("https://")))
516 && !s->accept_range) {
517 pstrcpy(state->errmsg, CURL_ERROR_SIZE,
518 "Server does not support 'range' (byte ranges).");
519 goto out;
520 }
521 DPRINTF("CURL: Size = %zd\n", s->len);
522
523 curl_clean_state(state);
524 curl_easy_cleanup(state->curl);
525 state->curl = NULL;
526
527 aio_timer_init(bdrv_get_aio_context(bs), &s->timer,
528 QEMU_CLOCK_REALTIME, SCALE_NS,
529 curl_multi_timeout_do, s);
530
531 // Now we know the file exists and its size, so let's
532 // initialize the multi interface!
533
534 s->multi = curl_multi_init();
535 curl_multi_setopt(s->multi, CURLMOPT_SOCKETDATA, s);
536 curl_multi_setopt(s->multi, CURLMOPT_SOCKETFUNCTION, curl_sock_cb);
537 #ifdef NEED_CURL_TIMER_CALLBACK
538 curl_multi_setopt(s->multi, CURLMOPT_TIMERDATA, s);
539 curl_multi_setopt(s->multi, CURLMOPT_TIMERFUNCTION, curl_timer_cb);
540 #endif
541 curl_multi_do(s);
542
543 qemu_opts_del(opts);
544 return 0;
545
546 out:
547 error_setg(errp, "CURL: Error opening file: %s", state->errmsg);
548 curl_easy_cleanup(state->curl);
549 state->curl = NULL;
550 out_noclean:
551 g_free(s->url);
552 qemu_opts_del(opts);
553 return -EINVAL;
554 }
555
556 static void curl_aio_cancel(BlockDriverAIOCB *blockacb)
557 {
558 // Do we have to implement canceling? Seems to work without...
559 }
560
561 static const AIOCBInfo curl_aiocb_info = {
562 .aiocb_size = sizeof(CURLAIOCB),
563 .cancel = curl_aio_cancel,
564 };
565
566
567 static void curl_readv_bh_cb(void *p)
568 {
569 CURLState *state;
570
571 CURLAIOCB *acb = p;
572 BDRVCURLState *s = acb->common.bs->opaque;
573
574 qemu_bh_delete(acb->bh);
575 acb->bh = NULL;
576
577 size_t start = acb->sector_num * SECTOR_SIZE;
578 size_t end;
579
580 // In case we have the requested data already (e.g. read-ahead),
581 // we can just call the callback and be done.
582 switch (curl_find_buf(s, start, acb->nb_sectors * SECTOR_SIZE, acb)) {
583 case FIND_RET_OK:
584 qemu_aio_release(acb);
585 // fall through
586 case FIND_RET_WAIT:
587 return;
588 default:
589 break;
590 }
591
592 // No cache found, so let's start a new request
593 state = curl_init_state(s);
594 if (!state) {
595 acb->common.cb(acb->common.opaque, -EIO);
596 qemu_aio_release(acb);
597 return;
598 }
599
600 acb->start = 0;
601 acb->end = (acb->nb_sectors * SECTOR_SIZE);
602
603 state->buf_off = 0;
604 if (state->orig_buf)
605 g_free(state->orig_buf);
606 state->buf_start = start;
607 state->buf_len = acb->end + s->readahead_size;
608 end = MIN(start + state->buf_len, s->len) - 1;
609 state->orig_buf = g_malloc(state->buf_len);
610 state->acb[0] = acb;
611
612 snprintf(state->range, 127, "%zd-%zd", start, end);
613 DPRINTF("CURL (AIO): Reading %d at %zd (%s)\n",
614 (acb->nb_sectors * SECTOR_SIZE), start, state->range);
615 curl_easy_setopt(state->curl, CURLOPT_RANGE, state->range);
616
617 curl_multi_add_handle(s->multi, state->curl);
618 curl_multi_do(s);
619
620 }
621
622 static BlockDriverAIOCB *curl_aio_readv(BlockDriverState *bs,
623 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
624 BlockDriverCompletionFunc *cb, void *opaque)
625 {
626 CURLAIOCB *acb;
627
628 acb = qemu_aio_get(&curl_aiocb_info, bs, cb, opaque);
629
630 acb->qiov = qiov;
631 acb->sector_num = sector_num;
632 acb->nb_sectors = nb_sectors;
633
634 acb->bh = qemu_bh_new(curl_readv_bh_cb, acb);
635 qemu_bh_schedule(acb->bh);
636 return &acb->common;
637 }
638
639 static void curl_close(BlockDriverState *bs)
640 {
641 BDRVCURLState *s = bs->opaque;
642 int i;
643
644 DPRINTF("CURL: Close\n");
645 for (i=0; i<CURL_NUM_STATES; i++) {
646 if (s->states[i].in_use)
647 curl_clean_state(&s->states[i]);
648 if (s->states[i].curl) {
649 curl_easy_cleanup(s->states[i].curl);
650 s->states[i].curl = NULL;
651 }
652 if (s->states[i].orig_buf) {
653 g_free(s->states[i].orig_buf);
654 s->states[i].orig_buf = NULL;
655 }
656 }
657 if (s->multi)
658 curl_multi_cleanup(s->multi);
659
660 timer_del(&s->timer);
661
662 g_free(s->url);
663 }
664
665 static int64_t curl_getlength(BlockDriverState *bs)
666 {
667 BDRVCURLState *s = bs->opaque;
668 return s->len;
669 }
670
671 static BlockDriver bdrv_http = {
672 .format_name = "http",
673 .protocol_name = "http",
674
675 .instance_size = sizeof(BDRVCURLState),
676 .bdrv_parse_filename = curl_parse_filename,
677 .bdrv_file_open = curl_open,
678 .bdrv_close = curl_close,
679 .bdrv_getlength = curl_getlength,
680
681 .bdrv_aio_readv = curl_aio_readv,
682 };
683
684 static BlockDriver bdrv_https = {
685 .format_name = "https",
686 .protocol_name = "https",
687
688 .instance_size = sizeof(BDRVCURLState),
689 .bdrv_parse_filename = curl_parse_filename,
690 .bdrv_file_open = curl_open,
691 .bdrv_close = curl_close,
692 .bdrv_getlength = curl_getlength,
693
694 .bdrv_aio_readv = curl_aio_readv,
695 };
696
697 static BlockDriver bdrv_ftp = {
698 .format_name = "ftp",
699 .protocol_name = "ftp",
700
701 .instance_size = sizeof(BDRVCURLState),
702 .bdrv_parse_filename = curl_parse_filename,
703 .bdrv_file_open = curl_open,
704 .bdrv_close = curl_close,
705 .bdrv_getlength = curl_getlength,
706
707 .bdrv_aio_readv = curl_aio_readv,
708 };
709
710 static BlockDriver bdrv_ftps = {
711 .format_name = "ftps",
712 .protocol_name = "ftps",
713
714 .instance_size = sizeof(BDRVCURLState),
715 .bdrv_parse_filename = curl_parse_filename,
716 .bdrv_file_open = curl_open,
717 .bdrv_close = curl_close,
718 .bdrv_getlength = curl_getlength,
719
720 .bdrv_aio_readv = curl_aio_readv,
721 };
722
723 static BlockDriver bdrv_tftp = {
724 .format_name = "tftp",
725 .protocol_name = "tftp",
726
727 .instance_size = sizeof(BDRVCURLState),
728 .bdrv_parse_filename = curl_parse_filename,
729 .bdrv_file_open = curl_open,
730 .bdrv_close = curl_close,
731 .bdrv_getlength = curl_getlength,
732
733 .bdrv_aio_readv = curl_aio_readv,
734 };
735
736 static void curl_block_init(void)
737 {
738 bdrv_register(&bdrv_http);
739 bdrv_register(&bdrv_https);
740 bdrv_register(&bdrv_ftp);
741 bdrv_register(&bdrv_ftps);
742 bdrv_register(&bdrv_tftp);
743 }
744
745 block_init(curl_block_init);