util: make do_send_recv work with partial send/recv

According to msdn documentation and Linux man pages, send() should try
to send as much as possible in blocking mode, while recv() may return
earlier with a smaller available amount, we should try to continue
send/recv from there.

Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20221006113657.2656108-3-marcandre.lureau@redhat.com>
This commit is contained in:
Marc-André Lureau 2022-10-06 15:36:53 +04:00
parent c1f7980913
commit 3f08376c2e

View File

@ -111,12 +111,17 @@ do_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt, bool do_send)
/*XXX Note: windows has WSASend() and WSARecv() */
unsigned i = 0;
ssize_t ret = 0;
ssize_t off = 0;
while (i < iov_cnt) {
ssize_t r = do_send
? send(sockfd, iov[i].iov_base, iov[i].iov_len, 0)
: recv(sockfd, iov[i].iov_base, iov[i].iov_len, 0);
? send(sockfd, iov[i].iov_base + off, iov[i].iov_len - off, 0)
: recv(sockfd, iov[i].iov_base + off, iov[i].iov_len - off, 0);
if (r > 0) {
ret += r;
off += r;
if (off < iov[i].iov_len) {
continue;
}
} else if (!r) {
break;
} else if (errno == EINTR) {
@ -129,6 +134,7 @@ do_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt, bool do_send)
}
break;
}
off = 0;
i++;
}
return ret;