Commit 43f35cb5 authored by Peter Lieven's avatar Peter Lieven Committed by Kevin Wolf
Browse files

util: add qemu_iovec_is_zero 



Signed-off-by: default avatarPeter Lieven <pl@kamp.de>
Signed-off-by: default avatarKevin Wolf <kwolf@redhat.com>
parent d66e5cee

include/qemu-common.h

+1 −0
Original line number Diff line number Diff line
@@ -318,6 +318,7 @@ void qemu_iovec_concat(QEMUIOVector *dst, 
void qemu_iovec_concat_iov(QEMUIOVector *dst,

                           struct iovec *src_iov, unsigned int src_cnt,

                           size_t soffset, size_t sbytes);

bool qemu_iovec_is_zero(QEMUIOVector *qiov);

void qemu_iovec_destroy(QEMUIOVector *qiov);

void qemu_iovec_reset(QEMUIOVector *qiov);

size_t qemu_iovec_to_buf(QEMUIOVector *qiov, size_t offset,

util/iov.c

+21 −0
Original line number Diff line number Diff line
@@ -335,6 +335,27 @@ void qemu_iovec_concat(QEMUIOVector *dst, 
    qemu_iovec_concat_iov(dst, src->iov, src->niov, soffset, sbytes);

}



/*

 * Check if the contents of the iovecs are all zero

 */

bool qemu_iovec_is_zero(QEMUIOVector *qiov)

{

    int i;

    for (i = 0; i < qiov->niov; i++) {

        size_t offs = QEMU_ALIGN_DOWN(qiov->iov[i].iov_len, 4 * sizeof(long));

        uint8_t *ptr = qiov->iov[i].iov_base;

        if (offs && !buffer_is_zero(qiov->iov[i].iov_base, offs)) {

            return false;

        }

        for (; offs < qiov->iov[i].iov_len; offs++) {

            if (ptr[offs]) {

                return false;

            }

        }

    }

    return true;

}



void qemu_iovec_destroy(QEMUIOVector *qiov)

{

    assert(qiov->nalloc != -1);