Commit cb6247a7 authored by Paolo Bonzini's avatar Paolo Bonzini
Browse files

iov: reorganize iov_send_recv, part 1 



Once the initial part of the iov is dropped, it is not used anymore.
Modify iov/iovcnt directly instead of adjusting them with the "si"
variable.

Reviewed-by: default avatarJuan Quintela <quintela@redhat.com>
Reviewed-by: default avatarOrit Wassermann <owasserm@redhat.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent 15711565

util/iov.c

+13 −7
Original line number Diff line number Diff line
@@ -159,16 +159,22 @@ ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt, 
    for (si = 0; si < iov_cnt && offset >= iov[si].iov_len; ++si) {

        offset -= iov[si].iov_len;

    }

    if (offset) {



    /* si == iov_cnt would only be valid if bytes == 0, which

     * we already ruled out above.  */

    assert(si < iov_cnt);

    iov += si;

    iov_cnt -= si;



    if (offset) {

        /* second, skip `offset' bytes from the (now) first element,

         * undo it on exit */

        iov[si].iov_base += offset;

        iov[si].iov_len -= offset;

        iov[0].iov_base += offset;

        iov[0].iov_len -= offset;

    }

    /* Find the end position skipping `bytes' bytes: */

    /* first, skip all full-sized elements */

    for (ei = si; ei < iov_cnt && iov[ei].iov_len <= bytes; ++ei) {

    for (ei = 0; ei < iov_cnt && iov[ei].iov_len <= bytes; ++ei) {

        bytes -= iov[ei].iov_len;

    }

    if (bytes) {
@@ -183,12 +189,12 @@ ssize_t iov_send_recv(int sockfd, struct iovec *iov, unsigned iov_cnt, 
        ++ei;

    }



    ret = do_send_recv(sockfd, iov + si, ei - si, do_send);

    ret = do_send_recv(sockfd, iov, ei, do_send);



    /* Undo the changes above */

    if (offset) {

        iov[si].iov_base -= offset;

        iov[si].iov_len += offset;

        iov[0].iov_base -= offset;

        iov[0].iov_len += offset;

    }

    if (bytes) {

        iov[ei-1].iov_len += bytes;