On 12/12/2014 at 05:35 PM, in message <20141212093545.GD136165@orkuz.home>, Jiri Denemark <jdenemar@redhat.com> wrote: On Fri, Dec 12, 2014 at 10:18:36 +0100, Peter Krempa wrote: On 12/12/14 10:04, Chunyan Liu wrote: Add public API virDomainSendSysrq for sending SysRequest key.
Signed-off-by: Chunyan Liu <cyliu@suse.com> --- include/libvirt/libvirt-domain.h | 3 +++ src/driver-hypervisor.h | 4 ++++ src/libvirt-domain.c | 38 ++++++++++++++++++++++++++++++++++++++ src/libvirt_public.syms | 1 + 4 files changed, 46 insertions(+)
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diff --git a/src/libvirt-domain.c b/src/libvirt-domain.c index cb76d8c..4658fd7 100644 --- a/src/libvirt-domain.c +++ b/src/libvirt-domain.c @@ -11192,3 +11192,41 @@ virDomainFSInfoFree(virDomainFSInfoPtr info) VIR_FREE(info->devAlias[i]); VIR_FREE(info->devAlias); } + + +/** + * virDomainSendSysrq: + * @domain: pointer to domain object, or NULL for Domain0 + * @key: SysRq key, like h, c, ... + * + * Send SysRq key to the guest. + * + * Returns 0 in case of success, -1 in case of failure. + */ +int +virDomainSendSysrq(virDomainPtr domain, const char *key)
The new API should definitely have a 'flags' argument although it may be unused for now.
Moreover, passing a single character by reference sounds pretty strange, why not just "char key"?
I tried to define as 'char key', but meet some trouble in remote protocol, +struct remote_domain_send_sysrq_args { + remote_nonnull_domain dom; + char key; +}; will report 'char key' as unsupported type.
Moreover, wouldn't it be better to provide an enum of possible values with meaningful names (rather than keys), such as
typedef enum { VIR_DOMAIN_SYSRQ_REBOOT, VIR_DOMAIN_SYSRQ_CRASH, VIR_DOMAIN_SYSRQ_OOM_KILL, VIR_DOMAIN_SYSRQ_SYNC, ... } virDomainSysrqCommand;
This way, virDomainSendSysrq(dom, VIR_DOMAIN_SYSRQ_OOM_KILL, 0) would be pretty self-explaining. The prototype would have to change to
Mainly because xen/libxl API both accept letter as parameter directly, so define enum will need to map enum to letter before calling xen/libxl API. Chunyan
int virDomainSendSysrq(virDomainPtr domain, int command, /* one of virDomainSysrqCommand */ unsigned int flags);
Jirka