]> git.proxmox.com Git - qemu.git/blob - block/curl.c
qemu-tool: Stub out qemu-timer functions
[qemu.git] / block / curl.c
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_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 #define CURL_NUM_STATES 8
38 #define CURL_NUM_ACB 8
39 #define SECTOR_SIZE 512
40 #define READ_AHEAD_SIZE (256 * 1024)
41
42 #define FIND_RET_NONE 0
43 #define FIND_RET_OK 1
44 #define FIND_RET_WAIT 2
45
46 struct BDRVCURLState;
47
48 typedef struct CURLAIOCB {
49 BlockDriverAIOCB common;
50 QEMUIOVector *qiov;
51 size_t start;
52 size_t end;
53 } CURLAIOCB;
54
55 typedef struct CURLState
56 {
57 struct BDRVCURLState *s;
58 CURLAIOCB *acb[CURL_NUM_ACB];
59 CURL *curl;
60 char *orig_buf;
61 size_t buf_start;
62 size_t buf_off;
63 size_t buf_len;
64 char range[128];
65 char errmsg[CURL_ERROR_SIZE];
66 char in_use;
67 } CURLState;
68
69 typedef struct BDRVCURLState {
70 CURLM *multi;
71 size_t len;
72 CURLState states[CURL_NUM_STATES];
73 char *url;
74 size_t readahead_size;
75 } BDRVCURLState;
76
77 static void curl_clean_state(CURLState *s);
78 static void curl_multi_do(void *arg);
79
80 static int curl_sock_cb(CURL *curl, curl_socket_t fd, int action,
81 void *s, void *sp)
82 {
83 DPRINTF("CURL (AIO): Sock action %d on fd %d\n", action, fd);
84 switch (action) {
85 case CURL_POLL_IN:
86 qemu_aio_set_fd_handler(fd, curl_multi_do, NULL, NULL, NULL, s);
87 break;
88 case CURL_POLL_OUT:
89 qemu_aio_set_fd_handler(fd, NULL, curl_multi_do, NULL, NULL, s);
90 break;
91 case CURL_POLL_INOUT:
92 qemu_aio_set_fd_handler(fd, curl_multi_do,
93 curl_multi_do, NULL, NULL, s);
94 break;
95 case CURL_POLL_REMOVE:
96 qemu_aio_set_fd_handler(fd, NULL, NULL, NULL, NULL, NULL);
97 break;
98 }
99
100 return 0;
101 }
102
103 static size_t curl_size_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
104 {
105 CURLState *s = ((CURLState*)opaque);
106 size_t realsize = size * nmemb;
107 size_t fsize;
108
109 if(sscanf(ptr, "Content-Length: %zd", &fsize) == 1) {
110 s->s->len = fsize;
111 }
112
113 return realsize;
114 }
115
116 static size_t curl_read_cb(void *ptr, size_t size, size_t nmemb, void *opaque)
117 {
118 CURLState *s = ((CURLState*)opaque);
119 size_t realsize = size * nmemb;
120 int i;
121
122 DPRINTF("CURL: Just reading %zd bytes\n", realsize);
123
124 if (!s || !s->orig_buf)
125 goto read_end;
126
127 memcpy(s->orig_buf + s->buf_off, ptr, realsize);
128 s->buf_off += realsize;
129
130 for(i=0; i<CURL_NUM_ACB; i++) {
131 CURLAIOCB *acb = s->acb[i];
132
133 if (!acb)
134 continue;
135
136 if ((s->buf_off >= acb->end)) {
137 qemu_iovec_from_buffer(acb->qiov, s->orig_buf + acb->start,
138 acb->end - acb->start);
139 acb->common.cb(acb->common.opaque, 0);
140 qemu_aio_release(acb);
141 s->acb[i] = NULL;
142 }
143 }
144
145 read_end:
146 return realsize;
147 }
148
149 static int curl_find_buf(BDRVCURLState *s, size_t start, size_t len,
150 CURLAIOCB *acb)
151 {
152 int i;
153 size_t end = start + len;
154
155 for (i=0; i<CURL_NUM_STATES; i++) {
156 CURLState *state = &s->states[i];
157 size_t buf_end = (state->buf_start + state->buf_off);
158 size_t buf_fend = (state->buf_start + state->buf_len);
159
160 if (!state->orig_buf)
161 continue;
162 if (!state->buf_off)
163 continue;
164
165 // Does the existing buffer cover our section?
166 if ((start >= state->buf_start) &&
167 (start <= buf_end) &&
168 (end >= state->buf_start) &&
169 (end <= buf_end))
170 {
171 char *buf = state->orig_buf + (start - state->buf_start);
172
173 qemu_iovec_from_buffer(acb->qiov, buf, len);
174 acb->common.cb(acb->common.opaque, 0);
175
176 return FIND_RET_OK;
177 }
178
179 // Wait for unfinished chunks
180 if ((start >= state->buf_start) &&
181 (start <= buf_fend) &&
182 (end >= state->buf_start) &&
183 (end <= buf_fend))
184 {
185 int j;
186
187 acb->start = start - state->buf_start;
188 acb->end = acb->start + len;
189
190 for (j=0; j<CURL_NUM_ACB; j++) {
191 if (!state->acb[j]) {
192 state->acb[j] = acb;
193 return FIND_RET_WAIT;
194 }
195 }
196 }
197 }
198
199 return FIND_RET_NONE;
200 }
201
202 static void curl_multi_do(void *arg)
203 {
204 BDRVCURLState *s = (BDRVCURLState *)arg;
205 int running;
206 int r;
207 int msgs_in_queue;
208
209 if (!s->multi)
210 return;
211
212 do {
213 r = curl_multi_socket_all(s->multi, &running);
214 } while(r == CURLM_CALL_MULTI_PERFORM);
215
216 /* Try to find done transfers, so we can free the easy
217 * handle again. */
218 do {
219 CURLMsg *msg;
220 msg = curl_multi_info_read(s->multi, &msgs_in_queue);
221
222 if (!msg)
223 break;
224 if (msg->msg == CURLMSG_NONE)
225 break;
226
227 switch (msg->msg) {
228 case CURLMSG_DONE:
229 {
230 CURLState *state = NULL;
231 curl_easy_getinfo(msg->easy_handle, CURLINFO_PRIVATE, (char**)&state);
232 curl_clean_state(state);
233 break;
234 }
235 default:
236 msgs_in_queue = 0;
237 break;
238 }
239 } while(msgs_in_queue);
240 }
241
242 static CURLState *curl_init_state(BDRVCURLState *s)
243 {
244 CURLState *state = NULL;
245 int i, j;
246
247 do {
248 for (i=0; i<CURL_NUM_STATES; i++) {
249 for (j=0; j<CURL_NUM_ACB; j++)
250 if (s->states[i].acb[j])
251 continue;
252 if (s->states[i].in_use)
253 continue;
254
255 state = &s->states[i];
256 state->in_use = 1;
257 break;
258 }
259 if (!state) {
260 usleep(100);
261 curl_multi_do(s);
262 }
263 } while(!state);
264
265 if (state->curl)
266 goto has_curl;
267
268 state->curl = curl_easy_init();
269 if (!state->curl)
270 return NULL;
271 curl_easy_setopt(state->curl, CURLOPT_URL, s->url);
272 curl_easy_setopt(state->curl, CURLOPT_TIMEOUT, 5);
273 curl_easy_setopt(state->curl, CURLOPT_WRITEFUNCTION, (void *)curl_read_cb);
274 curl_easy_setopt(state->curl, CURLOPT_WRITEDATA, (void *)state);
275 curl_easy_setopt(state->curl, CURLOPT_PRIVATE, (void *)state);
276 curl_easy_setopt(state->curl, CURLOPT_AUTOREFERER, 1);
277 curl_easy_setopt(state->curl, CURLOPT_FOLLOWLOCATION, 1);
278 curl_easy_setopt(state->curl, CURLOPT_NOSIGNAL, 1);
279 curl_easy_setopt(state->curl, CURLOPT_ERRORBUFFER, state->errmsg);
280
281 #ifdef DEBUG_VERBOSE
282 curl_easy_setopt(state->curl, CURLOPT_VERBOSE, 1);
283 #endif
284
285 has_curl:
286
287 state->s = s;
288
289 return state;
290 }
291
292 static void curl_clean_state(CURLState *s)
293 {
294 if (s->s->multi)
295 curl_multi_remove_handle(s->s->multi, s->curl);
296 s->in_use = 0;
297 }
298
299 static int curl_open(BlockDriverState *bs, const char *filename, int flags)
300 {
301 BDRVCURLState *s = bs->opaque;
302 CURLState *state = NULL;
303 double d;
304
305 #define RA_OPTSTR ":readahead="
306 char *file;
307 char *ra;
308 const char *ra_val;
309 int parse_state = 0;
310
311 static int inited = 0;
312
313 file = qemu_strdup(filename);
314 s->readahead_size = READ_AHEAD_SIZE;
315
316 /* Parse a trailing ":readahead=#:" param, if present. */
317 ra = file + strlen(file) - 1;
318 while (ra >= file) {
319 if (parse_state == 0) {
320 if (*ra == ':')
321 parse_state++;
322 else
323 break;
324 } else if (parse_state == 1) {
325 if (*ra > '9' || *ra < '0') {
326 char *opt_start = ra - strlen(RA_OPTSTR) + 1;
327 if (opt_start > file &&
328 strncmp(opt_start, RA_OPTSTR, strlen(RA_OPTSTR)) == 0) {
329 ra_val = ra + 1;
330 ra -= strlen(RA_OPTSTR) - 1;
331 *ra = '\0';
332 s->readahead_size = atoi(ra_val);
333 break;
334 } else {
335 break;
336 }
337 }
338 }
339 ra--;
340 }
341
342 if ((s->readahead_size & 0x1ff) != 0) {
343 fprintf(stderr, "HTTP_READAHEAD_SIZE %zd is not a multiple of 512\n",
344 s->readahead_size);
345 goto out_noclean;
346 }
347
348 if (!inited) {
349 curl_global_init(CURL_GLOBAL_ALL);
350 inited = 1;
351 }
352
353 DPRINTF("CURL: Opening %s\n", file);
354 s->url = file;
355 state = curl_init_state(s);
356 if (!state)
357 goto out_noclean;
358
359 // Get file size
360
361 curl_easy_setopt(state->curl, CURLOPT_NOBODY, 1);
362 curl_easy_setopt(state->curl, CURLOPT_WRITEFUNCTION, (void *)curl_size_cb);
363 if (curl_easy_perform(state->curl))
364 goto out;
365 curl_easy_getinfo(state->curl, CURLINFO_CONTENT_LENGTH_DOWNLOAD, &d);
366 curl_easy_setopt(state->curl, CURLOPT_WRITEFUNCTION, (void *)curl_read_cb);
367 curl_easy_setopt(state->curl, CURLOPT_NOBODY, 0);
368 if (d)
369 s->len = (size_t)d;
370 else if(!s->len)
371 goto out;
372 DPRINTF("CURL: Size = %zd\n", s->len);
373
374 curl_clean_state(state);
375 curl_easy_cleanup(state->curl);
376 state->curl = NULL;
377
378 // Now we know the file exists and its size, so let's
379 // initialize the multi interface!
380
381 s->multi = curl_multi_init();
382 curl_multi_setopt( s->multi, CURLMOPT_SOCKETDATA, s);
383 curl_multi_setopt( s->multi, CURLMOPT_SOCKETFUNCTION, curl_sock_cb );
384 curl_multi_do(s);
385
386 return 0;
387
388 out:
389 fprintf(stderr, "CURL: Error opening file: %s\n", state->errmsg);
390 curl_easy_cleanup(state->curl);
391 state->curl = NULL;
392 out_noclean:
393 qemu_free(file);
394 return -EINVAL;
395 }
396
397 static void curl_aio_cancel(BlockDriverAIOCB *blockacb)
398 {
399 // Do we have to implement canceling? Seems to work without...
400 }
401
402 static AIOPool curl_aio_pool = {
403 .aiocb_size = sizeof(CURLAIOCB),
404 .cancel = curl_aio_cancel,
405 };
406
407 static BlockDriverAIOCB *curl_aio_readv(BlockDriverState *bs,
408 int64_t sector_num, QEMUIOVector *qiov, int nb_sectors,
409 BlockDriverCompletionFunc *cb, void *opaque)
410 {
411 BDRVCURLState *s = bs->opaque;
412 CURLAIOCB *acb;
413 size_t start = sector_num * SECTOR_SIZE;
414 size_t end;
415 CURLState *state;
416
417 acb = qemu_aio_get(&curl_aio_pool, bs, cb, opaque);
418 if (!acb)
419 return NULL;
420
421 acb->qiov = qiov;
422
423 // In case we have the requested data already (e.g. read-ahead),
424 // we can just call the callback and be done.
425
426 switch (curl_find_buf(s, start, nb_sectors * SECTOR_SIZE, acb)) {
427 case FIND_RET_OK:
428 qemu_aio_release(acb);
429 // fall through
430 case FIND_RET_WAIT:
431 return &acb->common;
432 default:
433 break;
434 }
435
436 // No cache found, so let's start a new request
437
438 state = curl_init_state(s);
439 if (!state)
440 return NULL;
441
442 acb->start = 0;
443 acb->end = (nb_sectors * SECTOR_SIZE);
444
445 state->buf_off = 0;
446 if (state->orig_buf)
447 qemu_free(state->orig_buf);
448 state->buf_start = start;
449 state->buf_len = acb->end + s->readahead_size;
450 end = MIN(start + state->buf_len, s->len) - 1;
451 state->orig_buf = qemu_malloc(state->buf_len);
452 state->acb[0] = acb;
453
454 snprintf(state->range, 127, "%zd-%zd", start, end);
455 DPRINTF("CURL (AIO): Reading %d at %zd (%s)\n",
456 (nb_sectors * SECTOR_SIZE), start, state->range);
457 curl_easy_setopt(state->curl, CURLOPT_RANGE, state->range);
458
459 curl_multi_add_handle(s->multi, state->curl);
460 curl_multi_do(s);
461
462 return &acb->common;
463 }
464
465 static void curl_close(BlockDriverState *bs)
466 {
467 BDRVCURLState *s = bs->opaque;
468 int i;
469
470 DPRINTF("CURL: Close\n");
471 for (i=0; i<CURL_NUM_STATES; i++) {
472 if (s->states[i].in_use)
473 curl_clean_state(&s->states[i]);
474 if (s->states[i].curl) {
475 curl_easy_cleanup(s->states[i].curl);
476 s->states[i].curl = NULL;
477 }
478 if (s->states[i].orig_buf) {
479 qemu_free(s->states[i].orig_buf);
480 s->states[i].orig_buf = NULL;
481 }
482 }
483 if (s->multi)
484 curl_multi_cleanup(s->multi);
485 if (s->url)
486 free(s->url);
487 }
488
489 static int64_t curl_getlength(BlockDriverState *bs)
490 {
491 BDRVCURLState *s = bs->opaque;
492 return s->len;
493 }
494
495 static BlockDriver bdrv_http = {
496 .format_name = "http",
497 .protocol_name = "http",
498
499 .instance_size = sizeof(BDRVCURLState),
500 .bdrv_file_open = curl_open,
501 .bdrv_close = curl_close,
502 .bdrv_getlength = curl_getlength,
503
504 .bdrv_aio_readv = curl_aio_readv,
505 };
506
507 static BlockDriver bdrv_https = {
508 .format_name = "https",
509 .protocol_name = "https",
510
511 .instance_size = sizeof(BDRVCURLState),
512 .bdrv_file_open = curl_open,
513 .bdrv_close = curl_close,
514 .bdrv_getlength = curl_getlength,
515
516 .bdrv_aio_readv = curl_aio_readv,
517 };
518
519 static BlockDriver bdrv_ftp = {
520 .format_name = "ftp",
521 .protocol_name = "ftp",
522
523 .instance_size = sizeof(BDRVCURLState),
524 .bdrv_file_open = curl_open,
525 .bdrv_close = curl_close,
526 .bdrv_getlength = curl_getlength,
527
528 .bdrv_aio_readv = curl_aio_readv,
529 };
530
531 static BlockDriver bdrv_ftps = {
532 .format_name = "ftps",
533 .protocol_name = "ftps",
534
535 .instance_size = sizeof(BDRVCURLState),
536 .bdrv_file_open = curl_open,
537 .bdrv_close = curl_close,
538 .bdrv_getlength = curl_getlength,
539
540 .bdrv_aio_readv = curl_aio_readv,
541 };
542
543 static BlockDriver bdrv_tftp = {
544 .format_name = "tftp",
545 .protocol_name = "tftp",
546
547 .instance_size = sizeof(BDRVCURLState),
548 .bdrv_file_open = curl_open,
549 .bdrv_close = curl_close,
550 .bdrv_getlength = curl_getlength,
551
552 .bdrv_aio_readv = curl_aio_readv,
553 };
554
555 static void curl_block_init(void)
556 {
557 bdrv_register(&bdrv_http);
558 bdrv_register(&bdrv_https);
559 bdrv_register(&bdrv_ftp);
560 bdrv_register(&bdrv_ftps);
561 bdrv_register(&bdrv_tftp);
562 }
563
564 block_init(curl_block_init);