mirror of https://gitee.com/openkylin/qemu.git
91 lines
3.0 KiB
C
91 lines
3.0 KiB
C
/*
|
|
* Coroutine-aware I/O functions
|
|
*
|
|
* Copyright (C) 2009-2010 Nippon Telegraph and Telephone Corporation.
|
|
* Copyright (c) 2011, Red Hat, Inc.
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
* of this software and associated documentation files (the "Software"), to deal
|
|
* in the Software without restriction, including without limitation the rights
|
|
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
|
|
* copies of the Software, and to permit persons to whom the Software is
|
|
* furnished to do so, subject to the following conditions:
|
|
*
|
|
* The above copyright notice and this permission notice shall be included in
|
|
* all copies or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
|
|
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
|
|
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
|
|
* THE SOFTWARE.
|
|
*/
|
|
#include "qemu/osdep.h"
|
|
#include "qemu-common.h"
|
|
#include "qemu/sockets.h"
|
|
#include "qemu/coroutine.h"
|
|
#include "qemu/iov.h"
|
|
#include "qemu/main-loop.h"
|
|
|
|
ssize_t coroutine_fn
|
|
qemu_co_sendv_recvv(int sockfd, struct iovec *iov, unsigned iov_cnt,
|
|
size_t offset, size_t bytes, bool do_send)
|
|
{
|
|
size_t done = 0;
|
|
ssize_t ret;
|
|
while (done < bytes) {
|
|
ret = iov_send_recv(sockfd, iov, iov_cnt,
|
|
offset + done, bytes - done, do_send);
|
|
if (ret > 0) {
|
|
done += ret;
|
|
} else if (ret < 0) {
|
|
if (errno == EAGAIN || errno == EWOULDBLOCK) {
|
|
qemu_coroutine_yield();
|
|
} else if (done == 0) {
|
|
return -errno;
|
|
} else {
|
|
break;
|
|
}
|
|
} else if (ret == 0 && !do_send) {
|
|
/* write (send) should never return 0.
|
|
* read (recv) returns 0 for end-of-file (-data).
|
|
* In both cases there's little point retrying,
|
|
* but we do for write anyway, just in case */
|
|
break;
|
|
}
|
|
}
|
|
return done;
|
|
}
|
|
|
|
ssize_t coroutine_fn
|
|
qemu_co_send_recv(int sockfd, void *buf, size_t bytes, bool do_send)
|
|
{
|
|
struct iovec iov = { .iov_base = buf, .iov_len = bytes };
|
|
return qemu_co_sendv_recvv(sockfd, &iov, 1, 0, bytes, do_send);
|
|
}
|
|
|
|
typedef struct {
|
|
Coroutine *co;
|
|
int fd;
|
|
} FDYieldUntilData;
|
|
|
|
static void fd_coroutine_enter(void *opaque)
|
|
{
|
|
FDYieldUntilData *data = opaque;
|
|
qemu_set_fd_handler(data->fd, NULL, NULL, NULL);
|
|
qemu_coroutine_enter(data->co);
|
|
}
|
|
|
|
void coroutine_fn yield_until_fd_readable(int fd)
|
|
{
|
|
FDYieldUntilData data;
|
|
|
|
assert(qemu_in_coroutine());
|
|
data.co = qemu_coroutine_self();
|
|
data.fd = fd;
|
|
qemu_set_fd_handler(fd, fd_coroutine_enter, NULL, &data);
|
|
qemu_coroutine_yield();
|
|
}
|