On 04/28/2016 04:04 AM, Michal Privoznik wrote:
This API can be used to tell the other side of the stream to skip some bytes in the stream. This can be used to create a sparse file on the receiving side of a stream.
It takes just one argument @offset, which says how big the hole is. Since our streams are not rewindable like regular files, we don't need @whence argument like seek(2) has.
Signed-off-by: Michal Privoznik <mprivozn@redhat.com> --- include/libvirt/libvirt-stream.h | 3 +++ src/driver-stream.h | 5 +++++ src/libvirt-stream.c | 40 ++++++++++++++++++++++++++++++++++++++++ src/libvirt_public.syms | 5 +++++ 4 files changed, 53 insertions(+)
+++ b/src/libvirt-stream.c @@ -286,6 +286,46 @@ virStreamRecv(virStreamPtr stream,
/** + * virStreamSkip: + * @stream: pointer to the stream object + * @offset: number of bytes to skip + * + * Skip @offset bytes in the stream. This is useful when there's + * no actual data in the stream, just a hole. If that's the case, + * this API can be used to skip the hole properly instead of + * transmitting zeroes to the other side. + * + * Returns 0 on success, + * -1 error + */ +int +virStreamSkip(virStreamPtr stream, + unsigned long long offset)
'offset' is a bit misleading - you're not skipping _to_ the given offset, so much as _over_ length bytes. I'd name it 'length'. Otherwise looks okay. -- Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org