2 * QEMU Block driver for CURL images
4 * Copyright (c) 2009 Alexander Graf <agraf@suse.de>
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:
13 * The above copyright notice and this permission notice shall be included in
14 * all copies or substantial portions of the Software.
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
24 #include "qemu-common.h"
25 #include "block_int.h"
26 #include <curl/curl.h>
29 // #define DEBUG_VERBOSE
32 #define DPRINTF(fmt, ...) do { printf(fmt, ## __VA_ARGS__); } while (0)
34 #define DPRINTF(fmt, ...) do { } while (0)
37 #define CURL_NUM_STATES 8
38 #define CURL_NUM_ACB 8
39 #define SECTOR_SIZE 512
40 #define READ_AHEAD_SIZE (256 * 1024)
42 #define FIND_RET_NONE 0
44 #define FIND_RET_WAIT 2
48 typedef struct CURLAIOCB
{
49 BlockDriverAIOCB common
;
55 typedef struct CURLState
57 struct BDRVCURLState
*s
;
58 CURLAIOCB
*acb
[CURL_NUM_ACB
];
65 char errmsg
[CURL_ERROR_SIZE
];
69 typedef struct BDRVCURLState
{
72 CURLState states
[CURL_NUM_STATES
];
74 size_t readahead_size
;
77 static void curl_clean_state(CURLState
*s
);
78 static void curl_multi_do(void *arg
);
80 static int curl_sock_cb(CURL
*curl
, curl_socket_t fd
, int action
,
83 DPRINTF("CURL (AIO): Sock action %d on fd %d\n", action
, fd
);
86 qemu_aio_set_fd_handler(fd
, curl_multi_do
, NULL
, NULL
, NULL
, s
);
89 qemu_aio_set_fd_handler(fd
, NULL
, curl_multi_do
, NULL
, NULL
, s
);
92 qemu_aio_set_fd_handler(fd
, curl_multi_do
,
93 curl_multi_do
, NULL
, NULL
, s
);
95 case CURL_POLL_REMOVE
:
96 qemu_aio_set_fd_handler(fd
, NULL
, NULL
, NULL
, NULL
, NULL
);
103 static size_t curl_size_cb(void *ptr
, size_t size
, size_t nmemb
, void *opaque
)
105 CURLState
*s
= ((CURLState
*)opaque
);
106 size_t realsize
= size
* nmemb
;
109 if(sscanf(ptr
, "Content-Length: %zd", &fsize
) == 1) {
116 static size_t curl_read_cb(void *ptr
, size_t size
, size_t nmemb
, void *opaque
)
118 CURLState
*s
= ((CURLState
*)opaque
);
119 size_t realsize
= size
* nmemb
;
122 DPRINTF("CURL: Just reading %zd bytes\n", realsize
);
124 if (!s
|| !s
->orig_buf
)
127 memcpy(s
->orig_buf
+ s
->buf_off
, ptr
, realsize
);
128 s
->buf_off
+= realsize
;
130 for(i
=0; i
<CURL_NUM_ACB
; i
++) {
131 CURLAIOCB
*acb
= s
->acb
[i
];
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
);
149 static int curl_find_buf(BDRVCURLState
*s
, size_t start
, size_t len
,
153 size_t end
= start
+ len
;
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
);
160 if (!state
->orig_buf
)
165 // Does the existing buffer cover our section?
166 if ((start
>= state
->buf_start
) &&
167 (start
<= buf_end
) &&
168 (end
>= state
->buf_start
) &&
171 char *buf
= state
->orig_buf
+ (start
- state
->buf_start
);
173 qemu_iovec_from_buffer(acb
->qiov
, buf
, len
);
174 acb
->common
.cb(acb
->common
.opaque
, 0);
179 // Wait for unfinished chunks
180 if ((start
>= state
->buf_start
) &&
181 (start
<= buf_fend
) &&
182 (end
>= state
->buf_start
) &&
187 acb
->start
= start
- state
->buf_start
;
188 acb
->end
= acb
->start
+ len
;
190 for (j
=0; j
<CURL_NUM_ACB
; j
++) {
191 if (!state
->acb
[j
]) {
193 return FIND_RET_WAIT
;
199 return FIND_RET_NONE
;
202 static void curl_multi_do(void *arg
)
204 BDRVCURLState
*s
= (BDRVCURLState
*)arg
;
213 r
= curl_multi_socket_all(s
->multi
, &running
);
214 } while(r
== CURLM_CALL_MULTI_PERFORM
);
216 /* Try to find done transfers, so we can free the easy
220 msg
= curl_multi_info_read(s
->multi
, &msgs_in_queue
);
224 if (msg
->msg
== CURLMSG_NONE
)
230 CURLState
*state
= NULL
;
231 curl_easy_getinfo(msg
->easy_handle
, CURLINFO_PRIVATE
, (char**)&state
);
233 /* ACBs for successful messages get completed in curl_read_cb */
234 if (msg
->data
.result
!= CURLE_OK
) {
236 for (i
= 0; i
< CURL_NUM_ACB
; i
++) {
237 CURLAIOCB
*acb
= state
->acb
[i
];
243 acb
->common
.cb(acb
->common
.opaque
, -EIO
);
244 qemu_aio_release(acb
);
245 state
->acb
[i
] = NULL
;
249 curl_clean_state(state
);
256 } while(msgs_in_queue
);
259 static CURLState
*curl_init_state(BDRVCURLState
*s
)
261 CURLState
*state
= NULL
;
265 for (i
=0; i
<CURL_NUM_STATES
; i
++) {
266 for (j
=0; j
<CURL_NUM_ACB
; j
++)
267 if (s
->states
[i
].acb
[j
])
269 if (s
->states
[i
].in_use
)
272 state
= &s
->states
[i
];
285 state
->curl
= curl_easy_init();
288 curl_easy_setopt(state
->curl
, CURLOPT_URL
, s
->url
);
289 curl_easy_setopt(state
->curl
, CURLOPT_TIMEOUT
, 5);
290 curl_easy_setopt(state
->curl
, CURLOPT_WRITEFUNCTION
, (void *)curl_read_cb
);
291 curl_easy_setopt(state
->curl
, CURLOPT_WRITEDATA
, (void *)state
);
292 curl_easy_setopt(state
->curl
, CURLOPT_PRIVATE
, (void *)state
);
293 curl_easy_setopt(state
->curl
, CURLOPT_AUTOREFERER
, 1);
294 curl_easy_setopt(state
->curl
, CURLOPT_FOLLOWLOCATION
, 1);
295 curl_easy_setopt(state
->curl
, CURLOPT_NOSIGNAL
, 1);
296 curl_easy_setopt(state
->curl
, CURLOPT_ERRORBUFFER
, state
->errmsg
);
297 curl_easy_setopt(state
->curl
, CURLOPT_FAILONERROR
, 1);
300 curl_easy_setopt(state
->curl
, CURLOPT_VERBOSE
, 1);
310 static void curl_clean_state(CURLState
*s
)
313 curl_multi_remove_handle(s
->s
->multi
, s
->curl
);
317 static int curl_open(BlockDriverState
*bs
, const char *filename
, int flags
)
319 BDRVCURLState
*s
= bs
->opaque
;
320 CURLState
*state
= NULL
;
323 #define RA_OPTSTR ":readahead="
329 static int inited
= 0;
331 file
= g_strdup(filename
);
332 s
->readahead_size
= READ_AHEAD_SIZE
;
334 /* Parse a trailing ":readahead=#:" param, if present. */
335 ra
= file
+ strlen(file
) - 1;
337 if (parse_state
== 0) {
342 } else if (parse_state
== 1) {
343 if (*ra
> '9' || *ra
< '0') {
344 char *opt_start
= ra
- strlen(RA_OPTSTR
) + 1;
345 if (opt_start
> file
&&
346 strncmp(opt_start
, RA_OPTSTR
, strlen(RA_OPTSTR
)) == 0) {
348 ra
-= strlen(RA_OPTSTR
) - 1;
350 s
->readahead_size
= atoi(ra_val
);
360 if ((s
->readahead_size
& 0x1ff) != 0) {
361 fprintf(stderr
, "HTTP_READAHEAD_SIZE %zd is not a multiple of 512\n",
367 curl_global_init(CURL_GLOBAL_ALL
);
371 DPRINTF("CURL: Opening %s\n", file
);
373 state
= curl_init_state(s
);
379 curl_easy_setopt(state
->curl
, CURLOPT_NOBODY
, 1);
380 curl_easy_setopt(state
->curl
, CURLOPT_WRITEFUNCTION
, (void *)curl_size_cb
);
381 if (curl_easy_perform(state
->curl
))
383 curl_easy_getinfo(state
->curl
, CURLINFO_CONTENT_LENGTH_DOWNLOAD
, &d
);
384 curl_easy_setopt(state
->curl
, CURLOPT_WRITEFUNCTION
, (void *)curl_read_cb
);
385 curl_easy_setopt(state
->curl
, CURLOPT_NOBODY
, 0);
390 DPRINTF("CURL: Size = %zd\n", s
->len
);
392 curl_clean_state(state
);
393 curl_easy_cleanup(state
->curl
);
396 // Now we know the file exists and its size, so let's
397 // initialize the multi interface!
399 s
->multi
= curl_multi_init();
400 curl_multi_setopt( s
->multi
, CURLMOPT_SOCKETDATA
, s
);
401 curl_multi_setopt( s
->multi
, CURLMOPT_SOCKETFUNCTION
, curl_sock_cb
);
407 fprintf(stderr
, "CURL: Error opening file: %s\n", state
->errmsg
);
408 curl_easy_cleanup(state
->curl
);
415 static void curl_aio_cancel(BlockDriverAIOCB
*blockacb
)
417 // Do we have to implement canceling? Seems to work without...
420 static AIOPool curl_aio_pool
= {
421 .aiocb_size
= sizeof(CURLAIOCB
),
422 .cancel
= curl_aio_cancel
,
425 static BlockDriverAIOCB
*curl_aio_readv(BlockDriverState
*bs
,
426 int64_t sector_num
, QEMUIOVector
*qiov
, int nb_sectors
,
427 BlockDriverCompletionFunc
*cb
, void *opaque
)
429 BDRVCURLState
*s
= bs
->opaque
;
431 size_t start
= sector_num
* SECTOR_SIZE
;
435 acb
= qemu_aio_get(&curl_aio_pool
, bs
, cb
, opaque
);
441 // In case we have the requested data already (e.g. read-ahead),
442 // we can just call the callback and be done.
444 switch (curl_find_buf(s
, start
, nb_sectors
* SECTOR_SIZE
, acb
)) {
446 qemu_aio_release(acb
);
454 // No cache found, so let's start a new request
456 state
= curl_init_state(s
);
461 acb
->end
= (nb_sectors
* SECTOR_SIZE
);
465 g_free(state
->orig_buf
);
466 state
->buf_start
= start
;
467 state
->buf_len
= acb
->end
+ s
->readahead_size
;
468 end
= MIN(start
+ state
->buf_len
, s
->len
) - 1;
469 state
->orig_buf
= g_malloc(state
->buf_len
);
472 snprintf(state
->range
, 127, "%zd-%zd", start
, end
);
473 DPRINTF("CURL (AIO): Reading %d at %zd (%s)\n",
474 (nb_sectors
* SECTOR_SIZE
), start
, state
->range
);
475 curl_easy_setopt(state
->curl
, CURLOPT_RANGE
, state
->range
);
477 curl_multi_add_handle(s
->multi
, state
->curl
);
483 static void curl_close(BlockDriverState
*bs
)
485 BDRVCURLState
*s
= bs
->opaque
;
488 DPRINTF("CURL: Close\n");
489 for (i
=0; i
<CURL_NUM_STATES
; i
++) {
490 if (s
->states
[i
].in_use
)
491 curl_clean_state(&s
->states
[i
]);
492 if (s
->states
[i
].curl
) {
493 curl_easy_cleanup(s
->states
[i
].curl
);
494 s
->states
[i
].curl
= NULL
;
496 if (s
->states
[i
].orig_buf
) {
497 g_free(s
->states
[i
].orig_buf
);
498 s
->states
[i
].orig_buf
= NULL
;
502 curl_multi_cleanup(s
->multi
);
507 static int64_t curl_getlength(BlockDriverState
*bs
)
509 BDRVCURLState
*s
= bs
->opaque
;
513 static BlockDriver bdrv_http
= {
514 .format_name
= "http",
515 .protocol_name
= "http",
517 .instance_size
= sizeof(BDRVCURLState
),
518 .bdrv_file_open
= curl_open
,
519 .bdrv_close
= curl_close
,
520 .bdrv_getlength
= curl_getlength
,
522 .bdrv_aio_readv
= curl_aio_readv
,
525 static BlockDriver bdrv_https
= {
526 .format_name
= "https",
527 .protocol_name
= "https",
529 .instance_size
= sizeof(BDRVCURLState
),
530 .bdrv_file_open
= curl_open
,
531 .bdrv_close
= curl_close
,
532 .bdrv_getlength
= curl_getlength
,
534 .bdrv_aio_readv
= curl_aio_readv
,
537 static BlockDriver bdrv_ftp
= {
538 .format_name
= "ftp",
539 .protocol_name
= "ftp",
541 .instance_size
= sizeof(BDRVCURLState
),
542 .bdrv_file_open
= curl_open
,
543 .bdrv_close
= curl_close
,
544 .bdrv_getlength
= curl_getlength
,
546 .bdrv_aio_readv
= curl_aio_readv
,
549 static BlockDriver bdrv_ftps
= {
550 .format_name
= "ftps",
551 .protocol_name
= "ftps",
553 .instance_size
= sizeof(BDRVCURLState
),
554 .bdrv_file_open
= curl_open
,
555 .bdrv_close
= curl_close
,
556 .bdrv_getlength
= curl_getlength
,
558 .bdrv_aio_readv
= curl_aio_readv
,
561 static BlockDriver bdrv_tftp
= {
562 .format_name
= "tftp",
563 .protocol_name
= "tftp",
565 .instance_size
= sizeof(BDRVCURLState
),
566 .bdrv_file_open
= curl_open
,
567 .bdrv_close
= curl_close
,
568 .bdrv_getlength
= curl_getlength
,
570 .bdrv_aio_readv
= curl_aio_readv
,
573 static void curl_block_init(void)
575 bdrv_register(&bdrv_http
);
576 bdrv_register(&bdrv_https
);
577 bdrv_register(&bdrv_ftp
);
578 bdrv_register(&bdrv_ftps
);
579 bdrv_register(&bdrv_tftp
);
582 block_init(curl_block_init
);