qemu-e2k/qemu-coroutine-io.c
Michael Tokarev 3e80bf9351 rename qemu_sendv to iov_send, change proto and move declarations to iov.h
Rename arguments and use size_t for sizes instead of int,
from
 int
 qemu_sendv(int sockfd, struct iovec *iov,
            int len, int iov_offset)
to
 ssize_t
 iov_send(int sockfd, struct iovec *iov,
          size_t offset, size_t bytes)

The main motivation was to make it clear that length
and offset are in _bytes_, not in iov elements: it was
very confusing before, because all standard functions
which deals with iovecs expects number of iovs, not
bytes, even the fact that struct iovec has iov_len and
iov_ prefix does not help.  With "bytes" and "offset",
especially since they're now size_t, it is much more
explicit.  Also change the return type to be ssize_t
instead of int.

This also changes it to match other iov-related functons,
but not _quite_: there's still no argument indicating
where iovec ends, ie, no iov_cnt parameter as used
in iov_size() and friends.  If will be added in subsequent
patch/rewrite.

All callers of qemu_sendv() and qemu_recvv() and
related, like qemu_co_sendv() and qemu_co_recvv(),
were checked to verify that it is safe to use unsigned
datatype instead of int.

Note that the order of arguments is changed to: offset
and bytes (len and iov_offset) are swapped with each
other.  This is to make them consistent with very similar
functions from qemu_iovec family, where offset always
follows qiov, to mean the place in it to start from.

Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
2012-06-11 23:12:11 +04:00

98 lines
2.7 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-common.h"
#include "qemu_socket.h"
#include "qemu-coroutine.h"
#include "iov.h"
int coroutine_fn qemu_co_recvv(int sockfd, struct iovec *iov,
int len, int iov_offset)
{
int total = 0;
int ret;
while (len) {
ret = iov_recv(sockfd, iov, iov_offset + total, len);
if (ret < 0) {
if (errno == EAGAIN) {
qemu_coroutine_yield();
continue;
}
if (total == 0) {
total = -1;
}
break;
}
if (ret == 0) {
break;
}
total += ret, len -= ret;
}
return total;
}
int coroutine_fn qemu_co_sendv(int sockfd, struct iovec *iov,
int len, int iov_offset)
{
int total = 0;
int ret;
while (len) {
ret = iov_send(sockfd, iov, iov_offset + total, len);
if (ret < 0) {
if (errno == EAGAIN) {
qemu_coroutine_yield();
continue;
}
if (total == 0) {
total = -1;
}
break;
}
total += ret, len -= ret;
}
return total;
}
int coroutine_fn qemu_co_recv(int sockfd, void *buf, int len)
{
struct iovec iov;
iov.iov_base = buf;
iov.iov_len = len;
return qemu_co_recvv(sockfd, &iov, len, 0);
}
int coroutine_fn qemu_co_send(int sockfd, void *buf, int len)
{
struct iovec iov;
iov.iov_base = buf;
iov.iov_len = len;
return qemu_co_sendv(sockfd, &iov, len, 0);
}