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/*
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* QEMU Block driver for CURL images
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*
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* Copyright (c) 2009 Alexander Graf <agraf@suse.de>
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
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* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include "qemu-common.h" |
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#include "block_int.h" |
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#include <curl/curl.h> |
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// #define DEBUG
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// #define DEBUG_VERBOSE
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#ifdef DEBUG_CURL
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#define DPRINTF(fmt, ...) do { printf(fmt, ## __VA_ARGS__); } while (0) |
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#else
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#define DPRINTF(fmt, ...) do { } while (0) |
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#endif
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#define CURL_NUM_STATES 8 |
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#define CURL_NUM_ACB 8 |
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#define SECTOR_SIZE 512 |
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#define READ_AHEAD_SIZE (256 * 1024) |
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|
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#define FIND_RET_NONE 0 |
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#define FIND_RET_OK 1 |
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#define FIND_RET_WAIT 2 |
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|
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struct BDRVCURLState;
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|
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typedef struct CURLAIOCB { |
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BlockDriverAIOCB common; |
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QEMUIOVector *qiov; |
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size_t start; |
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size_t end; |
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} CURLAIOCB; |
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|
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typedef struct CURLState |
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{ |
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struct BDRVCURLState *s;
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CURLAIOCB *acb[CURL_NUM_ACB]; |
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CURL *curl; |
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char *orig_buf;
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size_t buf_start; |
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size_t buf_off; |
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size_t buf_len; |
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char range[128]; |
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char errmsg[CURL_ERROR_SIZE];
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char in_use;
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} CURLState; |
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typedef struct BDRVCURLState { |
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CURLM *multi; |
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size_t len; |
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CURLState states[CURL_NUM_STATES]; |
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char *url;
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size_t readahead_size; |
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} BDRVCURLState; |
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|
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static void curl_clean_state(CURLState *s); |
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static void curl_multi_do(void *arg); |
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|
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static int curl_sock_cb(CURL *curl, curl_socket_t fd, int action, |
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void *s, void *sp) |
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{ |
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DPRINTF("CURL (AIO): Sock action %d on fd %d\n", action, fd);
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switch (action) {
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case CURL_POLL_IN:
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qemu_aio_set_fd_handler(fd, curl_multi_do, NULL, NULL, NULL, s); |
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break;
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case CURL_POLL_OUT:
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qemu_aio_set_fd_handler(fd, NULL, curl_multi_do, NULL, NULL, s); |
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break;
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case CURL_POLL_INOUT:
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qemu_aio_set_fd_handler(fd, curl_multi_do, |
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curl_multi_do, NULL, NULL, s); |
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break;
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case CURL_POLL_REMOVE:
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qemu_aio_set_fd_handler(fd, NULL, NULL, NULL, NULL, NULL); |
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break;
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} |
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return 0; |
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} |
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|
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static size_t curl_size_cb(void *ptr, size_t size, size_t nmemb, void *opaque) |
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{ |
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CURLState *s = ((CURLState*)opaque); |
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size_t realsize = size * nmemb; |
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size_t fsize; |
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|
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if(sscanf(ptr, "Content-Length: %zd", &fsize) == 1) { |
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s->s->len = fsize; |
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} |
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return realsize;
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} |
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static size_t curl_read_cb(void *ptr, size_t size, size_t nmemb, void *opaque) |
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{ |
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CURLState *s = ((CURLState*)opaque); |
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size_t realsize = size * nmemb; |
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int i;
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DPRINTF("CURL: Just reading %zd bytes\n", realsize);
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if (!s || !s->orig_buf)
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goto read_end;
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memcpy(s->orig_buf + s->buf_off, ptr, realsize); |
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s->buf_off += realsize; |
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for(i=0; i<CURL_NUM_ACB; i++) { |
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CURLAIOCB *acb = s->acb[i]; |
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|
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if (!acb)
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continue;
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|
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if ((s->buf_off >= acb->end)) {
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qemu_iovec_from_buffer(acb->qiov, s->orig_buf + acb->start, |
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acb->end - acb->start); |
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acb->common.cb(acb->common.opaque, 0);
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qemu_aio_release(acb); |
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s->acb[i] = NULL;
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} |
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} |
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|
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read_end:
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return realsize;
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} |
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static int curl_find_buf(BDRVCURLState *s, size_t start, size_t len, |
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CURLAIOCB *acb) |
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{ |
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int i;
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size_t end = start + len; |
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|
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for (i=0; i<CURL_NUM_STATES; i++) { |
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CURLState *state = &s->states[i]; |
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size_t buf_end = (state->buf_start + state->buf_off); |
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size_t buf_fend = (state->buf_start + state->buf_len); |
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if (!state->orig_buf)
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continue;
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if (!state->buf_off)
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continue;
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// Does the existing buffer cover our section?
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if ((start >= state->buf_start) &&
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(start <= buf_end) && |
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(end >= state->buf_start) && |
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(end <= buf_end)) |
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{ |
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char *buf = state->orig_buf + (start - state->buf_start);
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qemu_iovec_from_buffer(acb->qiov, buf, len); |
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acb->common.cb(acb->common.opaque, 0);
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return FIND_RET_OK;
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} |
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// Wait for unfinished chunks
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if ((start >= state->buf_start) &&
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(start <= buf_fend) && |
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(end >= state->buf_start) && |
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(end <= buf_fend)) |
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{ |
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int j;
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acb->start = start - state->buf_start; |
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acb->end = acb->start + len; |
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for (j=0; j<CURL_NUM_ACB; j++) { |
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if (!state->acb[j]) {
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state->acb[j] = acb; |
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return FIND_RET_WAIT;
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} |
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} |
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} |
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} |
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return FIND_RET_NONE;
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} |
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static void curl_multi_do(void *arg) |
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{ |
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BDRVCURLState *s = (BDRVCURLState *)arg; |
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int running;
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int r;
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int msgs_in_queue;
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if (!s->multi)
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return;
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do {
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r = curl_multi_socket_all(s->multi, &running); |
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} while(r == CURLM_CALL_MULTI_PERFORM);
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/* Try to find done transfers, so we can free the easy
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* handle again. */
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do {
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CURLMsg *msg; |
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msg = curl_multi_info_read(s->multi, &msgs_in_queue); |
221 |
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if (!msg)
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break;
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if (msg->msg == CURLMSG_NONE)
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break;
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|
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switch (msg->msg) {
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case CURLMSG_DONE:
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{ |
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CURLState *state = NULL;
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curl_easy_getinfo(msg->easy_handle, CURLINFO_PRIVATE, (char**)&state);
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curl_clean_state(state); |
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break;
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} |
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default:
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msgs_in_queue = 0;
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break;
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} |
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} while(msgs_in_queue);
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} |
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static CURLState *curl_init_state(BDRVCURLState *s)
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{ |
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CURLState *state = NULL;
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int i, j;
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do {
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for (i=0; i<CURL_NUM_STATES; i++) { |
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for (j=0; j<CURL_NUM_ACB; j++) |
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if (s->states[i].acb[j])
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continue;
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if (s->states[i].in_use)
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continue;
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state = &s->states[i]; |
256 |
state->in_use = 1;
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break;
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} |
259 |
if (!state) {
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usleep(100);
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curl_multi_do(s); |
262 |
} |
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} while(!state);
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|
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if (state->curl)
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goto has_curl;
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state->curl = curl_easy_init(); |
269 |
if (!state->curl)
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return NULL; |
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curl_easy_setopt(state->curl, CURLOPT_URL, s->url); |
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curl_easy_setopt(state->curl, CURLOPT_TIMEOUT, 5);
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curl_easy_setopt(state->curl, CURLOPT_WRITEFUNCTION, (void *)curl_read_cb);
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curl_easy_setopt(state->curl, CURLOPT_WRITEDATA, (void *)state);
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curl_easy_setopt(state->curl, CURLOPT_PRIVATE, (void *)state);
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curl_easy_setopt(state->curl, CURLOPT_AUTOREFERER, 1);
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curl_easy_setopt(state->curl, CURLOPT_FOLLOWLOCATION, 1);
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curl_easy_setopt(state->curl, CURLOPT_NOSIGNAL, 1);
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curl_easy_setopt(state->curl, CURLOPT_ERRORBUFFER, state->errmsg); |
280 |
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#ifdef DEBUG_VERBOSE
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curl_easy_setopt(state->curl, CURLOPT_VERBOSE, 1);
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#endif
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284 |
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285 |
has_curl:
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286 |
|
287 |
state->s = s; |
288 |
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return state;
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} |
291 |
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static void curl_clean_state(CURLState *s) |
293 |
{ |
294 |
if (s->s->multi)
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curl_multi_remove_handle(s->s->multi, s->curl); |
296 |
s->in_use = 0;
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297 |
} |
298 |
|
299 |
static int curl_open(BlockDriverState *bs, const char *filename, int flags) |
300 |
{ |
301 |
BDRVCURLState *s = bs->opaque; |
302 |
CURLState *state = NULL;
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double d;
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304 |
|
305 |
#define RA_OPTSTR ":readahead=" |
306 |
char *file;
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307 |
char *ra;
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308 |
const char *ra_val; |
309 |
int parse_state = 0; |
310 |
|
311 |
static int inited = 0; |
312 |
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313 |
file = qemu_strdup(filename); |
314 |
s->readahead_size = READ_AHEAD_SIZE; |
315 |
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316 |
/* Parse a trailing ":readahead=#:" param, if present. */
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ra = file + strlen(file) - 1;
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318 |
while (ra >= file) {
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319 |
if (parse_state == 0) { |
320 |
if (*ra == ':') |
321 |
parse_state++; |
322 |
else
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break;
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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 &&
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328 |
strncmp(opt_start, RA_OPTSTR, strlen(RA_OPTSTR)) == 0) {
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329 |
ra_val = ra + 1;
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330 |
ra -= strlen(RA_OPTSTR) - 1;
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331 |
*ra = '\0';
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332 |
s->readahead_size = atoi(ra_val); |
333 |
break;
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334 |
} else {
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335 |
break;
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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",
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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);
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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); |