On Thu, May 19, 2011 at 04:51:25PM -0400, Laine Stump wrote:
From: Michal Privoznik <mprivozn@redhat.com>
--- src/libvirt.c | 141 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 files changed, 139 insertions(+), 2 deletions(-)
diff --git a/src/libvirt.c b/src/libvirt.c index ff16c48..786ce15 100644 --- a/src/libvirt.c +++ b/src/libvirt.c @@ -8143,7 +8143,9 @@ error: * @xml: the XML description for the interface, preferably in UTF-8 * @flags: and OR'ed set of extraction flags, not used yet * - * Define an interface (or modify existing interface configuration) + * Define an interface (or modify existing interface configuration). + * This can, however be affected by virInterfaceChangeBegin + * and/or friends.
Small nit, I would suggest making the 4 extra comments a bit more explicit that it's about transaction support, something along the lines of: * This can however be affected by the transaction support for * interface configuration change, see virInterfaceChangeBegin(), * virInterfaceChangeCommit() and related functions. [...]
@@ -8374,6 +8382,135 @@ virInterfaceFree(virInterfacePtr iface) return 0; }
+/** + * virInterfaceChangeBegin: + * @conn: pointer to hypervisor connection + * @flags: flags, not used yet + * + * This functions creates a restore point to which one can return + * later by calling virInterfaceChangeRollback. This function should + * be called before any transaction with interface configuration. + * Once knowing, new configuration works, it can be commited via + * virInterfaceChangeCommit, which frees restore point.
which frees the restore point. I would like the description of what happens ona sequence of virInterfaceChangeBegin() virInterfaceChangeBegin() calls for the same connection, is that an error ? Will netcf implement this, this behaviour should probably be documented.
+ * + * Returns 0 in case of success and -1 in case of failure. + */ +int +virInterfaceChangeBegin(virConnectPtr conn, unsigned int flags) +{ + int ret = -1; + + VIR_DEBUG("conn=%p, flags=%d", conn, flags); + + virResetLastError(); + + if (!VIR_IS_CONNECT(conn)) { + virLibConnError(VIR_ERR_INVALID_CONN, __FUNCTION__); + virDispatchError(NULL); + goto end; + } + + if (conn->flags & VIR_CONNECT_RO) { + virLibInterfaceError(VIR_ERR_OPERATION_DENIED, __FUNCTION__); + virDispatchError(conn); + goto end; + } + + if (conn->interfaceDriver && conn->interfaceDriver->interfaceChangeBegin) { + ret = conn->interfaceDriver->interfaceChangeBegin(conn, flags); + } else { + virLibConnError(VIR_ERR_NO_SUPPORT, __FUNCTION__); + } + +end: + VIR_DEBUG("returning: %d", ret); + return ret; +} + +/** + * virInterfaceChangeCommit: + * @conn: pointer to hypervisor connection + * @flags: flags, not used yet + * + * This commits the changes made to interfaces and frees restore point
"frees the restore point"
+ * created by virInterfaceChangeBegin.
Same thing behaviour of virInterfaceChangeCommit() in case there was no Begin() associated should be documented.
+ * Returns 0 in case of success and -1 in case of failure. + */ +int +virInterfaceChangeCommit(virConnectPtr conn, unsigned int flags) +{ + int ret = -1; + + VIR_DEBUG("conn=%p, flags=%d", conn, flags); + + virResetLastError(); + + if (!VIR_IS_CONNECT(conn)) { + virLibConnError(VIR_ERR_INVALID_CONN, __FUNCTION__); + virDispatchError(NULL); + goto end; + } + + if (conn->flags & VIR_CONNECT_RO) { + virLibInterfaceError(VIR_ERR_OPERATION_DENIED, __FUNCTION__); + virDispatchError(conn); + goto end; + } + + if (conn->interfaceDriver && conn->interfaceDriver->interfaceChangeCommit) { + ret = conn->interfaceDriver->interfaceChangeCommit(conn, flags); + } else { + virLibConnError(VIR_ERR_NO_SUPPORT, __FUNCTION__); + } + +end: + VIR_DEBUG("returning: %d", ret); + return ret; +} + +/** + * virInterfaceChangeRollback: + * @conn: pointer to hypervisor connection + * @flags: flags, not used yet + * + * This cancels changes made to interfaces settings by restoring previous + * state created by virInterfaceChangeBegin. + *
Same thing behaviour of virInterfaceChangeRollback() in case there was no Begin() associated should be documented.
+ * Returns 0 in case of success and -1 in case of failure. + */ +int +virInterfaceChangeRollback(virConnectPtr conn, unsigned int flags) +{ + int ret = -1; + + VIR_DEBUG("conn=%p, flags=%d", conn, flags); + + virResetLastError(); + + if (!VIR_IS_CONNECT(conn)) { + virLibConnError(VIR_ERR_INVALID_CONN, __FUNCTION__); + virDispatchError(NULL); + goto end; + } + + if (conn->flags & VIR_CONNECT_RO) { + virLibInterfaceError(VIR_ERR_OPERATION_DENIED, __FUNCTION__); + virDispatchError(conn); + goto end; + } + + if (conn->interfaceDriver && + conn->interfaceDriver->interfaceChangeRollback) { + ret = conn->interfaceDriver->interfaceChangeRollback(conn, flags); + } else { + virLibConnError(VIR_ERR_NO_SUPPORT, __FUNCTION__); + } + +end: + VIR_DEBUG("returning: %d", ret); + return ret; +}
[...] The partial code checking entry points seems fine but the real stuff happens somewhere else in netcf. I would like to have documented the behaviour in corner cases like I described but it would be good to clarify too what happens when 2 libvirt users/program/agents use simultanously those entry points targetting the same node. It seems to me virInterfaceChangeBegin() should be allowed only once on the full host before a Commit(), a Rollback() or a reboot happens, and if it's the case it should be documented in virInterfaceChangeBegin comment too. So with clarifications on semantic, ACK :-) Daniel -- Daniel Veillard | libxml Gnome XML XSLT toolkit http://xmlsoft.org/ daniel@veillard.com | Rpmfind RPM search engine http://rpmfind.net/ http://veillard.com/ | virtualization library http://libvirt.org/