libvirt/tools/virsh-util.c
Eric Blake 689beaa47c backup: Implement virsh support for checkpoints
Introduce a bunch of new virsh commands for managing checkpoints in
isolation. More commands are needed for performing incremental
backups, but these commands were easy to implement by modeling heavily
after virsh-snapshot.c. There is no need for checkpoint-revert or
checkpoint-current since those snapshot APIs have no checkpoint
counterpart.  Similarly, it is not necessary to change which
checkpoint is current when redefining from XML, since until we
integrate checkpoints with snapshots, there is only a linear chain
(and you can deduce the current checkpoint by instead using
'checkpoint-list --leaves').  Other aspects of checkpoint-list are
also a bit simpler than the snapshot counterpart, in part because we
don't have to cater to back-compat to older API.

Upcoming patches will test these interfaces once the test driver
supports checkpoints.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2019-07-26 16:48:58 -05:00

298 lines
6.9 KiB
C

/*
* virsh-util.c: helpers for virsh
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library. If not, see
* <http://www.gnu.org/licenses/>.
*/
#include <config.h>
#include "virsh-util.h"
#include "virfile.h"
#include "virstring.h"
#include "viralloc.h"
static virDomainPtr
virshLookupDomainInternal(vshControl *ctl,
const char *cmdname,
const char *name,
unsigned int flags)
{
virDomainPtr dom = NULL;
int id;
virCheckFlags(VIRSH_BYID | VIRSH_BYUUID | VIRSH_BYNAME, NULL);
virshControlPtr priv = ctl->privData;
/* try it by ID */
if (flags & VIRSH_BYID) {
if (virStrToLong_i(name, NULL, 10, &id) == 0 && id >= 0) {
vshDebug(ctl, VSH_ERR_DEBUG, "%s: <domain> looks like ID\n",
cmdname);
dom = virDomainLookupByID(priv->conn, id);
}
}
/* try it by UUID */
if (!dom && (flags & VIRSH_BYUUID) &&
strlen(name) == VIR_UUID_STRING_BUFLEN-1) {
vshDebug(ctl, VSH_ERR_DEBUG, "%s: <domain> trying as domain UUID\n",
cmdname);
dom = virDomainLookupByUUIDString(priv->conn, name);
}
/* try it by NAME */
if (!dom && (flags & VIRSH_BYNAME)) {
vshDebug(ctl, VSH_ERR_DEBUG, "%s: <domain> trying as domain NAME\n",
cmdname);
dom = virDomainLookupByName(priv->conn, name);
}
vshResetLibvirtError();
if (!dom)
vshError(ctl, _("failed to get domain '%s'"), name);
return dom;
}
virDomainPtr
virshLookupDomainBy(vshControl *ctl,
const char *name,
unsigned int flags)
{
return virshLookupDomainInternal(ctl, "unknown", name, flags);
}
virDomainPtr
virshCommandOptDomainBy(vshControl *ctl,
const vshCmd *cmd,
const char **name,
unsigned int flags)
{
const char *n = NULL;
const char *optname = "domain";
if (vshCommandOptStringReq(ctl, cmd, optname, &n) < 0)
return NULL;
vshDebug(ctl, VSH_ERR_INFO, "%s: found option <%s>: %s\n",
cmd->def->name, optname, n);
if (name)
*name = n;
return virshLookupDomainInternal(ctl, cmd->def->name, n, flags);
}
virDomainPtr
virshCommandOptDomain(vshControl *ctl,
const vshCmd *cmd,
const char **name)
{
return virshCommandOptDomainBy(ctl, cmd, name,
VIRSH_BYID | VIRSH_BYUUID | VIRSH_BYNAME);
}
int
virshDomainState(vshControl *ctl,
virDomainPtr dom,
int *reason)
{
virDomainInfo info;
virshControlPtr priv = ctl->privData;
if (reason)
*reason = -1;
if (!priv->useGetInfo) {
int state;
if (virDomainGetState(dom, &state, reason, 0) < 0) {
if (virGetLastErrorCode() == VIR_ERR_NO_SUPPORT)
priv->useGetInfo = true;
else
return -1;
} else {
return state;
}
}
/* fall back to virDomainGetInfo if virDomainGetState is not supported */
if (virDomainGetInfo(dom, &info) < 0)
return -1;
else
return info.state;
}
int
virshStreamSink(virStreamPtr st ATTRIBUTE_UNUSED,
const char *bytes,
size_t nbytes,
void *opaque)
{
int *fd = opaque;
return safewrite(*fd, bytes, nbytes);
}
int
virshStreamSource(virStreamPtr st ATTRIBUTE_UNUSED,
char *bytes,
size_t nbytes,
void *opaque)
{
virshStreamCallbackDataPtr cbData = opaque;
int fd = cbData->fd;
return saferead(fd, bytes, nbytes);
}
int
virshStreamSourceSkip(virStreamPtr st ATTRIBUTE_UNUSED,
long long offset,
void *opaque)
{
virshStreamCallbackDataPtr cbData = opaque;
int fd = cbData->fd;
off_t cur;
if ((cur = lseek(fd, offset, SEEK_CUR)) == (off_t) -1)
return -1;
return 0;
}
int
virshStreamSkip(virStreamPtr st ATTRIBUTE_UNUSED,
long long offset,
void *opaque)
{
int *fd = opaque;
off_t cur;
if ((cur = lseek(*fd, offset, SEEK_CUR)) == (off_t) -1)
return -1;
if (ftruncate(*fd, cur) < 0)
return -1;
return 0;
}
int
virshStreamInData(virStreamPtr st ATTRIBUTE_UNUSED,
int *inData,
long long *offset,
void *opaque)
{
virshStreamCallbackDataPtr cbData = opaque;
vshControl *ctl = cbData->ctl;
int fd = cbData->fd;
int ret;
if ((ret = virFileInData(fd, inData, offset)) < 0)
vshError(ctl, "%s", _("Unable to get current position in stream"));
return ret;
}
void
virshDomainFree(virDomainPtr dom)
{
if (!dom)
return;
vshSaveLibvirtHelperError();
virDomainFree(dom); /* sc_prohibit_obj_free_apis_in_virsh */
}
void
virshDomainCheckpointFree(virDomainCheckpointPtr chk)
{
if (!chk)
return;
vshSaveLibvirtHelperError();
virDomainCheckpointFree(chk); /* sc_prohibit_obj_free_apis_in_virsh */
}
void
virshDomainSnapshotFree(virDomainSnapshotPtr snap)
{
if (!snap)
return;
vshSaveLibvirtHelperError();
virDomainSnapshotFree(snap); /* sc_prohibit_obj_free_apis_in_virsh */
}
int
virshDomainGetXMLFromDom(vshControl *ctl,
virDomainPtr dom,
unsigned int flags,
xmlDocPtr *xml,
xmlXPathContextPtr *ctxt)
{
char *desc = NULL;
if (!(desc = virDomainGetXMLDesc(dom, flags))) {
vshError(ctl, _("Failed to get domain description xml"));
return -1;
}
*xml = virXMLParseStringCtxt(desc, _("(domain_definition)"), ctxt);
VIR_FREE(desc);
if (!(*xml)) {
vshError(ctl, _("Failed to parse domain description xml"));
return -1;
}
return 0;
}
int
virshDomainGetXML(vshControl *ctl,
const vshCmd *cmd,
unsigned int flags,
xmlDocPtr *xml,
xmlXPathContextPtr *ctxt)
{
virDomainPtr dom;
int ret;
if (!(dom = virshCommandOptDomain(ctl, cmd, NULL)))
return -1;
ret = virshDomainGetXMLFromDom(ctl, dom, flags, xml, ctxt);
virshDomainFree(dom);
return ret;
}