Re: [libvirt] [PATCH RFC 08/48] Introduce virStreamHoleSize

This function is basically a counterpart for virStreamSkip. If one side of a stream called virStreamSkip() the other should call virStreamHoleSize() to get the size of the hole. Signed-off-by: Michal Privoznik <mprivozn(a)redhat.com&gt; --- include/libvirt/libvirt-stream.h | 3 +++ src/driver-stream.h | 5 +++++ src/libvirt-stream.c | 42 ++++++++++++++++++++++++++++++++++++++++ src/libvirt_public.syms | 1 + 4 files changed, 51 insertions(+) diff --git a/include/libvirt/libvirt-stream.h b/include/libvirt/libvirt-stream.h index 4e0a599..2ebda74 100644 --- a/include/libvirt/libvirt-stream.h +++ b/include/libvirt/libvirt-stream.h @@ -53,6 +53,9 @@ int virStreamRecvFlags(virStreamPtr st, int virStreamSkip(virStreamPtr st, unsigned long long length); +int virStreamHoleSize(virStreamPtr, + unsigned long long *length); + /** * virStreamSourceFunc: diff --git a/src/driver-stream.h b/src/driver-stream.h index 20ea13f..e196b6d 100644 --- a/src/driver-stream.h +++ b/src/driver-stream.h @@ -46,6 +46,10 @@ typedef int unsigned long long length); typedef int +(*virDrvStreamHoleSize)(virStreamPtr st, + unsigned long long *length); + +typedef int (*virDrvStreamEventAddCallback)(virStreamPtr stream, int events, virStreamEventCallback cb, @@ -73,6 +77,7 @@ struct _virStreamDriver { virDrvStreamRecv streamRecv; virDrvStreamRecvFlags streamRecvFlags; virDrvStreamSkip streamSkip; + virDrvStreamHoleSize streamHoleSize; virDrvStreamEventAddCallback streamEventAddCallback; virDrvStreamEventUpdateCallback streamEventUpdateCallback; virDrvStreamEventRemoveCallback streamEventRemoveCallback; diff --git a/src/libvirt-stream.c b/src/libvirt-stream.c index 55f3ef5..3ac9e0d 100644 --- a/src/libvirt-stream.c +++ b/src/libvirt-stream.c @@ -403,6 +403,48 @@ virStreamSkip(virStreamPtr stream, /** + * virStreamHoleSize: + * @stream: pointer to the stream object + * @length: number of bytes to skip + * + * This function is a counterpart to virStreamSkip(). That is, if + * one side of a stream has called virStreamSkip() the other side + * of the stream should call virStreamHoleSize() to retrieve the + * size of hole. If there's currently no hole in the stream, -1 + * is returned. + * + * Returns 0 on success, + * -1 on error + */ +int +virStreamHoleSize(virStreamPtr stream, + unsigned long long *length) +{ + VIR_DEBUG("stream=%p, length=%p", stream, length); + + virResetLastError(); + + virCheckStreamReturn(stream, -1); + virCheckNonNullArgReturn(length, -1); + + if (stream->driver && + stream->driver->streamHoleSize) { + int ret; + ret = (stream->driver->streamHoleSize)(stream, length); + if (ret < 0) + goto error; + return ret; + } + + virReportUnsupportedError(); + + error: + virDispatchError(stream->conn); + return -1; +} + + +/** * virStreamSendAll: * @stream: pointer to the stream object * @handler: source callback for reading data from application diff --git a/src/libvirt_public.syms b/src/libvirt_public.syms index 5b536eb..0439434 100644 --- a/src/libvirt_public.syms +++ b/src/libvirt_public.syms @@ -738,6 +738,7 @@ LIBVIRT_2.0.0 { virDomainGetGuestVcpus; virDomainSetGuestVcpus; virConnectStoragePoolEventRegisterAny; + virStreamHoleSize; virStreamRecvFlags; virStreamSkip; } LIBVIRT_1.3.3;