libvirt/tools/virsh-snapshot.c

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/*
* virsh-snapshot.c: Commands to manage domain snapshot
*
virsh: Add snapshot-list --topological For snapshots, virsh already has a (shockingly naive [1]) client-side topological sorter with the --tree option. But as a series of REDEFINE calls must be presented in topological order, it's worth letting the server do the work for us, especially since the server can give us a topological sorting with less effort than our naive client reconstruction. [1] The XXX comment in virshSnapshotListCollect() about --tree being O(n^3) is telling; https://en.wikipedia.org/wiki/Topological_sorting is an interesting resource describing Kahn's algorithm and other approaches for O(n) topological sorting for anyone motivated to use a more elegant algorithm than brute force - but that doesn't affect this patch. For now, I am purposefully NOT implementing virsh fallback code to provide a topological sort when the flag was rejected as unsupported; we can worry about that down the road if users actually demonstrate that they use new virsh but old libvirt to even need the fallback. (The code we use for --tree could be repurposed to be such a fallback, whether or not we keep it naive or improve it to be faster - but again, no one should spend time on a fallback without evidence that we need it.) The test driver makes it easy to test: $ virsh -c test:///default ' snapshot-create-as test a snapshot-create-as test c snapshot-create-as test b snapshot-list test snapshot-list test --topological snapshot-list test --descendants a snapshot-list test --descendants a --topological snapshot-list test --tree snapshot-list test --tree --topological ' Without any flags, virsh does client-side sorting alphabetically, and lists 'b' before 'c' (even though 'c' is the parent of 'b'); with the flag, virsh skips sorting, and you can now see that the server handed back data in a correct ordering. As shown here with a simple linear chain, there isn't any other possible ordering, so --tree mode doesn't seem to care whether --topological is used. But it is possible to compose more complicated DAGs with multiple children to a parent (representing reverting back to a snapshot then creating more snapshots along those divergent execution timelines), where it is then possible (but not guaranteed) that adding the --topological flag changes the --tree output (the client-side --tree algorithm breaks ties based on alphabetical sorting between two nodes that share the same parent, while the --topological sort skips the client-side alphabetical sort and ends up exposing the server's internal order for siblings, whether that be historical creation order or dependent on a random hash seed). But even if the results differ, they will still be topologically correct. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com> Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2019-03-08 04:12:01 +00:00
* Copyright (C) 2005-2019 Red Hat, Inc.
*
* 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-snapshot.h"
#include <assert.h>
#include <libxml/parser.h>
#include <libxml/tree.h>
#include <libxml/xpath.h>
#include <libxml/xmlsave.h>
#include "internal.h"
#include "virbuffer.h"
2012-12-12 18:06:53 +00:00
#include "viralloc.h"
#include "virfile.h"
#include "virsh-util.h"
#include "virstring.h"
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#include "virxml.h"
#include "conf/virdomainsnapshotobjlist.h"
#include "vsh-table.h"
/* Helper for snapshot-create and snapshot-create-as */
static bool
virshSnapshotCreate(vshControl *ctl, virDomainPtr dom, const char *buffer,
unsigned int flags, const char *from)
{
bool ret = false;
virDomainSnapshotPtr snapshot;
bool halt = false;
const char *name = NULL;
snapshot = virDomainSnapshotCreateXML(dom, buffer, flags);
/* Emulate --halt on older servers. */
if (!snapshot && last_error->code == VIR_ERR_INVALID_ARG &&
(flags & VIR_DOMAIN_SNAPSHOT_CREATE_HALT)) {
int persistent;
vshResetLibvirtError();
persistent = virDomainIsPersistent(dom);
if (persistent < 0) {
virsh: use common namespacing Convert the exported items in virsh.h to use a common 'vsh' prefix. * tools/virsh.h (VIRSH_MAX_XML_FILE): Rename... (VSH_MAX_XML_FILE): ...and parenthesize. (DIFF_MSEC, CTRL_CLOSE_BRACKET): Delete. (vshUsage, vshInit, vshDeinit, vshParseArgv): Remove prototype. (editWriteToTempFile, editFile, editReadBackFile, prettyCapacity) (virshReportError): Rename... (vshEditWriteToTempFile, vshEditFile, vshEditReadBackFile) (vshPrettyCapacity, vshReportError): ...into vsh namespace. (jobWatchTimeoutFunc): Move to virsh-domain.c. * tools/virsh.c (vshCommandRun): Inline former DIFF_MSEC. (main): Inline former CTRL_CLOSE_BRACKET. (vshUsage, vshInit, vshDeinit, vshParseArgv): Make static. (prettyCapacity, virshReportError, editWriteToTempFile, editFile): Fix naming, and adjust usage. (vshAskReedit, vshCommandRun, vshEventLoop, vshInit): Adjust usage. * tools/virsh-domain.c (cmdAttachDevice, cmdCPUCompare) (cmdCPUBaseline, cmdCreate, cmdDefine, cmdDetachDevice) (cmdUpdateDevice, cmdDesc, cmdUndefine, cmdStart, cmdVcpucount) (cmdAttachDevice, cmdDomjobinfo): Likewise. * tools/virsh-edit.c (do): Likewise. * tools/virsh-interface.c (cmdInterfaceDefine): Likewise. * tools/virsh-network.c (cmdNetworkCreate, cmdNetworkDefine): Likewise. * tools/virsh-nodedev.c (cmdNodeDeviceCreate): Likewise. * tools/virsh-nwfilter.c (cmdNWFilterDefine): Likewise. * tools/virsh-pool.c (cmdPoolCreate, cmdPoolDefine) (cmdPoolDiscoverSources, cmdPoolList): Likewise. * tools/virsh-secret.c (cmdSecretDefine): Likewise. * tools/virsh-snapshot.c (cmdSnapshotCreate, vshSnapshotCreate) (vshLookupSnapshot, cmdSnapshotEdit, cmdSnapshotCurrent) (vshGetSnapshotParent): Likewise. * tools/virsh-volume.c (cmdVolCreate, cmdVolCreateFrom) (cmdVolInfo, cmdVolList): Likewise.
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vshReportError(ctl);
goto cleanup;
}
if (!persistent) {
vshError(ctl, "%s",
_("cannot halt after snapshot of transient domain"));
goto cleanup;
}
if (virDomainIsActive(dom) == 1)
halt = true;
flags &= ~VIR_DOMAIN_SNAPSHOT_CREATE_HALT;
snapshot = virDomainSnapshotCreateXML(dom, buffer, flags);
}
if (snapshot == NULL)
goto cleanup;
if (halt && virDomainDestroy(dom) < 0) {
virsh: use common namespacing Convert the exported items in virsh.h to use a common 'vsh' prefix. * tools/virsh.h (VIRSH_MAX_XML_FILE): Rename... (VSH_MAX_XML_FILE): ...and parenthesize. (DIFF_MSEC, CTRL_CLOSE_BRACKET): Delete. (vshUsage, vshInit, vshDeinit, vshParseArgv): Remove prototype. (editWriteToTempFile, editFile, editReadBackFile, prettyCapacity) (virshReportError): Rename... (vshEditWriteToTempFile, vshEditFile, vshEditReadBackFile) (vshPrettyCapacity, vshReportError): ...into vsh namespace. (jobWatchTimeoutFunc): Move to virsh-domain.c. * tools/virsh.c (vshCommandRun): Inline former DIFF_MSEC. (main): Inline former CTRL_CLOSE_BRACKET. (vshUsage, vshInit, vshDeinit, vshParseArgv): Make static. (prettyCapacity, virshReportError, editWriteToTempFile, editFile): Fix naming, and adjust usage. (vshAskReedit, vshCommandRun, vshEventLoop, vshInit): Adjust usage. * tools/virsh-domain.c (cmdAttachDevice, cmdCPUCompare) (cmdCPUBaseline, cmdCreate, cmdDefine, cmdDetachDevice) (cmdUpdateDevice, cmdDesc, cmdUndefine, cmdStart, cmdVcpucount) (cmdAttachDevice, cmdDomjobinfo): Likewise. * tools/virsh-edit.c (do): Likewise. * tools/virsh-interface.c (cmdInterfaceDefine): Likewise. * tools/virsh-network.c (cmdNetworkCreate, cmdNetworkDefine): Likewise. * tools/virsh-nodedev.c (cmdNodeDeviceCreate): Likewise. * tools/virsh-nwfilter.c (cmdNWFilterDefine): Likewise. * tools/virsh-pool.c (cmdPoolCreate, cmdPoolDefine) (cmdPoolDiscoverSources, cmdPoolList): Likewise. * tools/virsh-secret.c (cmdSecretDefine): Likewise. * tools/virsh-snapshot.c (cmdSnapshotCreate, vshSnapshotCreate) (vshLookupSnapshot, cmdSnapshotEdit, cmdSnapshotCurrent) (vshGetSnapshotParent): Likewise. * tools/virsh-volume.c (cmdVolCreate, cmdVolCreateFrom) (cmdVolInfo, cmdVolList): Likewise.
2012-08-19 04:10:17 +00:00
vshReportError(ctl);
goto cleanup;
}
name = virDomainSnapshotGetName(snapshot);
if (!name) {
vshError(ctl, "%s", _("Could not get snapshot name"));
goto cleanup;
}
if (from)
vshPrintExtra(ctl, _("Domain snapshot %s created from '%s'"), name, from);
else
vshPrintExtra(ctl, _("Domain snapshot %s created"), name);
ret = true;
cleanup:
virshDomainSnapshotFree(snapshot);
return ret;
}
/*
* "snapshot-create" command
*/
static const vshCmdInfo info_snapshot_create[] = {
{.name = "help",
.data = N_("Create a snapshot from XML")
},
{.name = "desc",
.data = N_("Create a snapshot (disk and RAM) from XML")
},
{.name = NULL}
};
static const vshCmdOptDef opts_snapshot_create[] = {
VIRSH_COMMON_OPT_DOMAIN_FULL(0),
{.name = "xmlfile",
.type = VSH_OT_STRING,
.help = N_("domain snapshot XML")
},
{.name = "redefine",
.type = VSH_OT_BOOL,
.help = N_("redefine metadata for existing snapshot")
},
VIRSH_COMMON_OPT_CURRENT(N_("with redefine, set current snapshot")),
{.name = "no-metadata",
.type = VSH_OT_BOOL,
.help = N_("take snapshot but create no metadata")
},
{.name = "halt",
.type = VSH_OT_BOOL,
.help = N_("halt domain after snapshot is created")
},
{.name = "disk-only",
.type = VSH_OT_BOOL,
.help = N_("capture disk state but not vm state")
},
{.name = "reuse-external",
.type = VSH_OT_BOOL,
.help = N_("reuse any existing external files")
},
{.name = "quiesce",
.type = VSH_OT_BOOL,
.help = N_("quiesce guest's file systems")
},
{.name = "atomic",
.type = VSH_OT_BOOL,
.help = N_("require atomic operation")
},
VIRSH_COMMON_OPT_LIVE(N_("take a live snapshot")),
{.name = NULL}
};
static bool
cmdSnapshotCreate(vshControl *ctl, const vshCmd *cmd)
{
virDomainPtr dom = NULL;
bool ret = false;
const char *from = NULL;
char *buffer = NULL;
unsigned int flags = 0;
if (vshCommandOptBool(cmd, "redefine"))
flags |= VIR_DOMAIN_SNAPSHOT_CREATE_REDEFINE;
if (vshCommandOptBool(cmd, "current"))
flags |= VIR_DOMAIN_SNAPSHOT_CREATE_CURRENT;
if (vshCommandOptBool(cmd, "no-metadata"))
flags |= VIR_DOMAIN_SNAPSHOT_CREATE_NO_METADATA;
if (vshCommandOptBool(cmd, "halt"))
flags |= VIR_DOMAIN_SNAPSHOT_CREATE_HALT;
if (vshCommandOptBool(cmd, "disk-only"))
flags |= VIR_DOMAIN_SNAPSHOT_CREATE_DISK_ONLY;
if (vshCommandOptBool(cmd, "reuse-external"))
flags |= VIR_DOMAIN_SNAPSHOT_CREATE_REUSE_EXT;
if (vshCommandOptBool(cmd, "quiesce"))
flags |= VIR_DOMAIN_SNAPSHOT_CREATE_QUIESCE;
if (vshCommandOptBool(cmd, "atomic"))
flags |= VIR_DOMAIN_SNAPSHOT_CREATE_ATOMIC;
if (vshCommandOptBool(cmd, "live"))
flags |= VIR_DOMAIN_SNAPSHOT_CREATE_LIVE;
if (!(dom = virshCommandOptDomain(ctl, cmd, NULL)))
goto cleanup;
if (vshCommandOptStringReq(ctl, cmd, "xmlfile", &from) < 0)
goto cleanup;
if (!from) {
buffer = vshStrdup(ctl, "<domainsnapshot/>");
} else {
virsh: use common namespacing Convert the exported items in virsh.h to use a common 'vsh' prefix. * tools/virsh.h (VIRSH_MAX_XML_FILE): Rename... (VSH_MAX_XML_FILE): ...and parenthesize. (DIFF_MSEC, CTRL_CLOSE_BRACKET): Delete. (vshUsage, vshInit, vshDeinit, vshParseArgv): Remove prototype. (editWriteToTempFile, editFile, editReadBackFile, prettyCapacity) (virshReportError): Rename... (vshEditWriteToTempFile, vshEditFile, vshEditReadBackFile) (vshPrettyCapacity, vshReportError): ...into vsh namespace. (jobWatchTimeoutFunc): Move to virsh-domain.c. * tools/virsh.c (vshCommandRun): Inline former DIFF_MSEC. (main): Inline former CTRL_CLOSE_BRACKET. (vshUsage, vshInit, vshDeinit, vshParseArgv): Make static. (prettyCapacity, virshReportError, editWriteToTempFile, editFile): Fix naming, and adjust usage. (vshAskReedit, vshCommandRun, vshEventLoop, vshInit): Adjust usage. * tools/virsh-domain.c (cmdAttachDevice, cmdCPUCompare) (cmdCPUBaseline, cmdCreate, cmdDefine, cmdDetachDevice) (cmdUpdateDevice, cmdDesc, cmdUndefine, cmdStart, cmdVcpucount) (cmdAttachDevice, cmdDomjobinfo): Likewise. * tools/virsh-edit.c (do): Likewise. * tools/virsh-interface.c (cmdInterfaceDefine): Likewise. * tools/virsh-network.c (cmdNetworkCreate, cmdNetworkDefine): Likewise. * tools/virsh-nodedev.c (cmdNodeDeviceCreate): Likewise. * tools/virsh-nwfilter.c (cmdNWFilterDefine): Likewise. * tools/virsh-pool.c (cmdPoolCreate, cmdPoolDefine) (cmdPoolDiscoverSources, cmdPoolList): Likewise. * tools/virsh-secret.c (cmdSecretDefine): Likewise. * tools/virsh-snapshot.c (cmdSnapshotCreate, vshSnapshotCreate) (vshLookupSnapshot, cmdSnapshotEdit, cmdSnapshotCurrent) (vshGetSnapshotParent): Likewise. * tools/virsh-volume.c (cmdVolCreate, cmdVolCreateFrom) (cmdVolInfo, cmdVolList): Likewise.
2012-08-19 04:10:17 +00:00
if (virFileReadAll(from, VSH_MAX_XML_FILE, &buffer) < 0) {
vshSaveLibvirtError();
goto cleanup;
}
}
ret = virshSnapshotCreate(ctl, dom, buffer, flags, from);
cleanup:
VIR_FREE(buffer);
virshDomainFree(dom);
return ret;
}
/*
* "snapshot-create-as" command
*/
static int
virshParseSnapshotMemspec(vshControl *ctl, virBufferPtr buf, const char *str)
{
int ret = -1;
const char *snapshot = NULL;
const char *file = NULL;
char **array = NULL;
int narray;
size_t i;
if (!str)
return 0;
narray = vshStringToArray(str, &array);
if (narray < 0)
goto cleanup;
for (i = 0; i < narray; i++) {
if (!snapshot && STRPREFIX(array[i], "snapshot="))
snapshot = array[i] + strlen("snapshot=");
else if (!file && STRPREFIX(array[i], "file="))
file = array[i] + strlen("file=");
else if (!file && *array[i] == '/')
file = array[i];
else
goto cleanup;
}
virBufferAddLit(buf, "<memory");
virBufferEscapeString(buf, " snapshot='%s'", snapshot);
virBufferEscapeString(buf, " file='%s'", file);
virBufferAddLit(buf, "/>\n");
ret = 0;
cleanup:
if (ret < 0)
vshError(ctl, _("unable to parse memspec: %s"), str);
virStringListFree(array);
return ret;
}
static int
virshParseSnapshotDiskspec(vshControl *ctl, virBufferPtr buf, const char *str)
{
int ret = -1;
const char *name = NULL;
const char *snapshot = NULL;
const char *driver = NULL;
const char *file = NULL;
char **array = NULL;
int narray;
size_t i;
narray = vshStringToArray(str, &array);
if (narray <= 0)
goto cleanup;
name = array[0];
for (i = 1; i < narray; i++) {
if (!snapshot && STRPREFIX(array[i], "snapshot="))
snapshot = array[i] + strlen("snapshot=");
else if (!driver && STRPREFIX(array[i], "driver="))
driver = array[i] + strlen("driver=");
else if (!file && STRPREFIX(array[i], "file="))
file = array[i] + strlen("file=");
else
goto cleanup;
}
virBufferEscapeString(buf, "<disk name='%s'", name);
if (snapshot)
virBufferAsprintf(buf, " snapshot='%s'", snapshot);
if (driver || file) {
virBufferAddLit(buf, ">\n");
virBufferAdjustIndent(buf, 2);
if (driver)
virBufferAsprintf(buf, "<driver type='%s'/>\n", driver);
if (file)
virBufferEscapeString(buf, "<source file='%s'/>\n", file);
virBufferAdjustIndent(buf, -2);
virBufferAddLit(buf, "</disk>\n");
} else {
virBufferAddLit(buf, "/>\n");
}
ret = 0;
cleanup:
if (ret < 0)
vshError(ctl, _("unable to parse diskspec: %s"), str);
virStringListFree(array);
return ret;
}
static const vshCmdInfo info_snapshot_create_as[] = {
{.name = "help",
.data = N_("Create a snapshot from a set of args")
},
{.name = "desc",
.data = N_("Create a snapshot (disk and RAM) from arguments")
},
{.name = NULL}
};
static const vshCmdOptDef opts_snapshot_create_as[] = {
VIRSH_COMMON_OPT_DOMAIN_FULL(0),
{.name = "name",
.type = VSH_OT_STRING,
.help = N_("name of snapshot")
},
{.name = "description",
.type = VSH_OT_STRING,
.help = N_("description of snapshot")
},
{.name = "print-xml",
.type = VSH_OT_BOOL,
.help = N_("print XML document rather than create")
},
{.name = "no-metadata",
.type = VSH_OT_BOOL,
.help = N_("take snapshot but create no metadata")
},
{.name = "halt",
.type = VSH_OT_BOOL,
.help = N_("halt domain after snapshot is created")
},
{.name = "disk-only",
.type = VSH_OT_BOOL,
.help = N_("capture disk state but not vm state")
},
{.name = "reuse-external",
.type = VSH_OT_BOOL,
.help = N_("reuse any existing external files")
},
{.name = "quiesce",
.type = VSH_OT_BOOL,
.help = N_("quiesce guest's file systems")
},
{.name = "atomic",
.type = VSH_OT_BOOL,
.help = N_("require atomic operation")
},
VIRSH_COMMON_OPT_LIVE(N_("take a live snapshot")),
{.name = "memspec",
.type = VSH_OT_STRING,
.flags = VSH_OFLAG_REQ_OPT,
.help = N_("memory attributes: [file=]name[,snapshot=type]")
},
{.name = "diskspec",
.type = VSH_OT_ARGV,
.help = N_("disk attributes: disk[,snapshot=type][,driver=type][,file=name]")
},
{.name = NULL}
};
static bool
cmdSnapshotCreateAs(vshControl *ctl, const vshCmd *cmd)
{
virDomainPtr dom = NULL;
bool ret = false;
char *buffer = NULL;
const char *name = NULL;
const char *desc = NULL;
const char *memspec = NULL;
virBuffer buf = VIR_BUFFER_INITIALIZER;
unsigned int flags = 0;
const vshCmdOpt *opt = NULL;
if (vshCommandOptBool(cmd, "no-metadata")) {
if (vshCommandOptBool(cmd, "print-xml")) {
vshError(ctl, "%s",
_("--print-xml is incompatible with --no-metadata"));
return false;
}
flags |= VIR_DOMAIN_SNAPSHOT_CREATE_NO_METADATA;
}
if (vshCommandOptBool(cmd, "halt"))
flags |= VIR_DOMAIN_SNAPSHOT_CREATE_HALT;
if (vshCommandOptBool(cmd, "disk-only"))
flags |= VIR_DOMAIN_SNAPSHOT_CREATE_DISK_ONLY;
if (vshCommandOptBool(cmd, "reuse-external"))
flags |= VIR_DOMAIN_SNAPSHOT_CREATE_REUSE_EXT;
if (vshCommandOptBool(cmd, "quiesce"))
flags |= VIR_DOMAIN_SNAPSHOT_CREATE_QUIESCE;
if (vshCommandOptBool(cmd, "atomic"))
flags |= VIR_DOMAIN_SNAPSHOT_CREATE_ATOMIC;
if (vshCommandOptBool(cmd, "live"))
flags |= VIR_DOMAIN_SNAPSHOT_CREATE_LIVE;
if (!(dom = virshCommandOptDomain(ctl, cmd, NULL)))
return false;
if (vshCommandOptStringReq(ctl, cmd, "name", &name) < 0 ||
vshCommandOptStringReq(ctl, cmd, "description", &desc) < 0)
goto cleanup;
virBufferAddLit(&buf, "<domainsnapshot>\n");
virBufferAdjustIndent(&buf, 2);
virBufferEscapeString(&buf, "<name>%s</name>\n", name);
virBufferEscapeString(&buf, "<description>%s</description>\n", desc);
if (vshCommandOptStringReq(ctl, cmd, "memspec", &memspec) < 0)
goto cleanup;
if (memspec && virshParseSnapshotMemspec(ctl, &buf, memspec) < 0)
goto cleanup;
if (vshCommandOptBool(cmd, "diskspec")) {
virBufferAddLit(&buf, "<disks>\n");
virBufferAdjustIndent(&buf, 2);
while ((opt = vshCommandOptArgv(ctl, cmd, opt))) {
if (virshParseSnapshotDiskspec(ctl, &buf, opt->data) < 0)
goto cleanup;
}
virBufferAdjustIndent(&buf, -2);
virBufferAddLit(&buf, "</disks>\n");
}
virBufferAdjustIndent(&buf, -2);
virBufferAddLit(&buf, "</domainsnapshot>\n");
if (virBufferError(&buf)) {
vshError(ctl, "%s", _("Out of memory"));
goto cleanup;
}
buffer = virBufferContentAndReset(&buf);
if (vshCommandOptBool(cmd, "print-xml")) {
vshPrint(ctl, "%s\n", buffer);
ret = true;
goto cleanup;
}
ret = virshSnapshotCreate(ctl, dom, buffer, flags, NULL);
cleanup:
virBufferFreeAndReset(&buf);
VIR_FREE(buffer);
virshDomainFree(dom);
return ret;
}
/* Helper for resolving {--current | --ARG name} into a snapshot
* belonging to DOM. If EXCLUSIVE, fail if both --current and arg are
* present. On success, populate *SNAP and *NAME, before returning 0.
* On failure, return -1 after issuing an error message. */
static int
virshLookupSnapshot(vshControl *ctl, const vshCmd *cmd,
const char *arg, bool exclusive, virDomainPtr dom,
virDomainSnapshotPtr *snap, const char **name)
{
bool current = vshCommandOptBool(cmd, "current");
const char *snapname = NULL;
if (vshCommandOptStringReq(ctl, cmd, arg, &snapname) < 0)
return -1;
if (exclusive && current && snapname) {
vshError(ctl, _("--%s and --current are mutually exclusive"), arg);
return -1;
}
if (snapname) {
*snap = virDomainSnapshotLookupByName(dom, snapname, 0);
} else if (current) {
*snap = virDomainSnapshotCurrent(dom, 0);
} else {
vshError(ctl, _("--%s or --current is required"), arg);
return -1;
}
if (!*snap) {
virsh: use common namespacing Convert the exported items in virsh.h to use a common 'vsh' prefix. * tools/virsh.h (VIRSH_MAX_XML_FILE): Rename... (VSH_MAX_XML_FILE): ...and parenthesize. (DIFF_MSEC, CTRL_CLOSE_BRACKET): Delete. (vshUsage, vshInit, vshDeinit, vshParseArgv): Remove prototype. (editWriteToTempFile, editFile, editReadBackFile, prettyCapacity) (virshReportError): Rename... (vshEditWriteToTempFile, vshEditFile, vshEditReadBackFile) (vshPrettyCapacity, vshReportError): ...into vsh namespace. (jobWatchTimeoutFunc): Move to virsh-domain.c. * tools/virsh.c (vshCommandRun): Inline former DIFF_MSEC. (main): Inline former CTRL_CLOSE_BRACKET. (vshUsage, vshInit, vshDeinit, vshParseArgv): Make static. (prettyCapacity, virshReportError, editWriteToTempFile, editFile): Fix naming, and adjust usage. (vshAskReedit, vshCommandRun, vshEventLoop, vshInit): Adjust usage. * tools/virsh-domain.c (cmdAttachDevice, cmdCPUCompare) (cmdCPUBaseline, cmdCreate, cmdDefine, cmdDetachDevice) (cmdUpdateDevice, cmdDesc, cmdUndefine, cmdStart, cmdVcpucount) (cmdAttachDevice, cmdDomjobinfo): Likewise. * tools/virsh-edit.c (do): Likewise. * tools/virsh-interface.c (cmdInterfaceDefine): Likewise. * tools/virsh-network.c (cmdNetworkCreate, cmdNetworkDefine): Likewise. * tools/virsh-nodedev.c (cmdNodeDeviceCreate): Likewise. * tools/virsh-nwfilter.c (cmdNWFilterDefine): Likewise. * tools/virsh-pool.c (cmdPoolCreate, cmdPoolDefine) (cmdPoolDiscoverSources, cmdPoolList): Likewise. * tools/virsh-secret.c (cmdSecretDefine): Likewise. * tools/virsh-snapshot.c (cmdSnapshotCreate, vshSnapshotCreate) (vshLookupSnapshot, cmdSnapshotEdit, cmdSnapshotCurrent) (vshGetSnapshotParent): Likewise. * tools/virsh-volume.c (cmdVolCreate, cmdVolCreateFrom) (cmdVolInfo, cmdVolList): Likewise.
2012-08-19 04:10:17 +00:00
vshReportError(ctl);
return -1;
}
*name = virDomainSnapshotGetName(*snap);
return 0;
}
/*
* "snapshot-edit" command
*/
static const vshCmdInfo info_snapshot_edit[] = {
{.name = "help",
.data = N_("edit XML for a snapshot")
},
{.name = "desc",
.data = N_("Edit the domain snapshot XML for a named snapshot")
},
{.name = NULL}
};
static const vshCmdOptDef opts_snapshot_edit[] = {
VIRSH_COMMON_OPT_DOMAIN_FULL(0),
{.name = "snapshotname",
.type = VSH_OT_STRING,
.help = N_("snapshot name"),
.completer = virshSnapshotNameCompleter,
},
VIRSH_COMMON_OPT_CURRENT(N_("also set edited snapshot as current")),
{.name = "rename",
.type = VSH_OT_BOOL,
.help = N_("allow renaming an existing snapshot")
},
{.name = "clone",
.type = VSH_OT_BOOL,
.help = N_("allow cloning to new name")
},
{.name = NULL}
};
static bool
cmdSnapshotEdit(vshControl *ctl, const vshCmd *cmd)
{
virDomainPtr dom = NULL;
virDomainSnapshotPtr snapshot = NULL;
virDomainSnapshotPtr edited = NULL;
const char *name = NULL;
const char *edited_name;
bool ret = false;
unsigned int getxml_flags = VIR_DOMAIN_XML_SECURE;
unsigned int define_flags = VIR_DOMAIN_SNAPSHOT_CREATE_REDEFINE;
bool rename_okay = vshCommandOptBool(cmd, "rename");
bool clone_okay = vshCommandOptBool(cmd, "clone");
VSH_EXCLUSIVE_OPTIONS_EXPR("rename", rename_okay, "clone", clone_okay)
if (vshCommandOptBool(cmd, "current") &&
vshCommandOptBool(cmd, "snapshotname"))
define_flags |= VIR_DOMAIN_SNAPSHOT_CREATE_CURRENT;
if (!(dom = virshCommandOptDomain(ctl, cmd, NULL)))
return false;
if (virshLookupSnapshot(ctl, cmd, "snapshotname", false, dom,
&snapshot, &name) < 0)
goto cleanup;
#define EDIT_GET_XML \
virDomainSnapshotGetXMLDesc(snapshot, getxml_flags)
#define EDIT_NOT_CHANGED \
do { \
/* Depending on flags, we re-edit even if XML is unchanged. */ \
if (!(define_flags & VIR_DOMAIN_SNAPSHOT_CREATE_CURRENT)) { \
vshPrintExtra(ctl, \
_("Snapshot %s XML configuration not changed.\n"), \
name); \
ret = true; \
goto edit_cleanup; \
} \
} while (0)
#define EDIT_DEFINE \
(strstr(doc, "<state>disk-snapshot</state>") ? \
define_flags |= VIR_DOMAIN_SNAPSHOT_CREATE_DISK_ONLY : 0), \
edited = virDomainSnapshotCreateXML(dom, doc_edited, define_flags)
#include "virsh-edit.c"
edited_name = virDomainSnapshotGetName(edited);
if (STREQ(name, edited_name)) {
vshPrintExtra(ctl, _("Snapshot %s edited.\n"), name);
} else if (clone_okay) {
vshPrintExtra(ctl, _("Snapshot %s cloned to %s.\n"), name,
edited_name);
} else {
unsigned int delete_flags;
delete_flags = VIR_DOMAIN_SNAPSHOT_DELETE_METADATA_ONLY;
if (virDomainSnapshotDelete(rename_okay ? snapshot : edited,
delete_flags) < 0) {
virsh: use common namespacing Convert the exported items in virsh.h to use a common 'vsh' prefix. * tools/virsh.h (VIRSH_MAX_XML_FILE): Rename... (VSH_MAX_XML_FILE): ...and parenthesize. (DIFF_MSEC, CTRL_CLOSE_BRACKET): Delete. (vshUsage, vshInit, vshDeinit, vshParseArgv): Remove prototype. (editWriteToTempFile, editFile, editReadBackFile, prettyCapacity) (virshReportError): Rename... (vshEditWriteToTempFile, vshEditFile, vshEditReadBackFile) (vshPrettyCapacity, vshReportError): ...into vsh namespace. (jobWatchTimeoutFunc): Move to virsh-domain.c. * tools/virsh.c (vshCommandRun): Inline former DIFF_MSEC. (main): Inline former CTRL_CLOSE_BRACKET. (vshUsage, vshInit, vshDeinit, vshParseArgv): Make static. (prettyCapacity, virshReportError, editWriteToTempFile, editFile): Fix naming, and adjust usage. (vshAskReedit, vshCommandRun, vshEventLoop, vshInit): Adjust usage. * tools/virsh-domain.c (cmdAttachDevice, cmdCPUCompare) (cmdCPUBaseline, cmdCreate, cmdDefine, cmdDetachDevice) (cmdUpdateDevice, cmdDesc, cmdUndefine, cmdStart, cmdVcpucount) (cmdAttachDevice, cmdDomjobinfo): Likewise. * tools/virsh-edit.c (do): Likewise. * tools/virsh-interface.c (cmdInterfaceDefine): Likewise. * tools/virsh-network.c (cmdNetworkCreate, cmdNetworkDefine): Likewise. * tools/virsh-nodedev.c (cmdNodeDeviceCreate): Likewise. * tools/virsh-nwfilter.c (cmdNWFilterDefine): Likewise. * tools/virsh-pool.c (cmdPoolCreate, cmdPoolDefine) (cmdPoolDiscoverSources, cmdPoolList): Likewise. * tools/virsh-secret.c (cmdSecretDefine): Likewise. * tools/virsh-snapshot.c (cmdSnapshotCreate, vshSnapshotCreate) (vshLookupSnapshot, cmdSnapshotEdit, cmdSnapshotCurrent) (vshGetSnapshotParent): Likewise. * tools/virsh-volume.c (cmdVolCreate, cmdVolCreateFrom) (cmdVolInfo, cmdVolList): Likewise.
2012-08-19 04:10:17 +00:00
vshReportError(ctl);
vshError(ctl, _("Failed to clean up %s"),
rename_okay ? name : edited_name);
goto cleanup;
}
if (!rename_okay) {
vshError(ctl, _("Must use --rename or --clone to change %s to %s"),
name, edited_name);
goto cleanup;
}
}
ret = true;
cleanup:
if (!ret && name)
vshError(ctl, _("Failed to update %s"), name);
virshDomainSnapshotFree(edited);
virshDomainSnapshotFree(snapshot);
virshDomainFree(dom);
return ret;
}
/*
* "snapshot-current" command
*/
static const vshCmdInfo info_snapshot_current[] = {
{.name = "help",
.data = N_("Get or set the current snapshot")
},
{.name = "desc",
.data = N_("Get or set the current snapshot")
},
{.name = NULL}
};
static const vshCmdOptDef opts_snapshot_current[] = {
VIRSH_COMMON_OPT_DOMAIN_FULL(0),
{.name = "name",
.type = VSH_OT_BOOL,
.help = N_("list the name, rather than the full xml")
},
{.name = "security-info",
.type = VSH_OT_BOOL,
.help = N_("include security sensitive information in XML dump")
},
{.name = "snapshotname",
.type = VSH_OT_STRING,
.help = N_("name of existing snapshot to make current"),
.completer = virshSnapshotNameCompleter,
},
{.name = NULL}
};
static bool
cmdSnapshotCurrent(vshControl *ctl, const vshCmd *cmd)
{
virDomainPtr dom = NULL;
bool ret = false;
int current;
virDomainSnapshotPtr snapshot = NULL;
char *xml = NULL;
const char *snapshotname = NULL;
unsigned int flags = 0;
const char *domname;
if (vshCommandOptBool(cmd, "security-info"))
flags |= VIR_DOMAIN_XML_SECURE;
VSH_EXCLUSIVE_OPTIONS("name", "snapshotname");
if (!(dom = virshCommandOptDomain(ctl, cmd, &domname)))
return false;
if (vshCommandOptStringReq(ctl, cmd, "snapshotname", &snapshotname) < 0)
goto cleanup;
if (snapshotname) {
virDomainSnapshotPtr snapshot2 = NULL;
flags = (VIR_DOMAIN_SNAPSHOT_CREATE_REDEFINE |
VIR_DOMAIN_SNAPSHOT_CREATE_CURRENT);
if (!(snapshot = virDomainSnapshotLookupByName(dom, snapshotname, 0)))
goto cleanup;
xml = virDomainSnapshotGetXMLDesc(snapshot, VIR_DOMAIN_XML_SECURE);
if (!xml)
goto cleanup;
/* strstr is safe here, since xml came from libvirt API and not user */
if (strstr(xml, "<state>disk-snapshot</state>"))
flags |= VIR_DOMAIN_SNAPSHOT_CREATE_DISK_ONLY;
if (!(snapshot2 = virDomainSnapshotCreateXML(dom, xml, flags)))
goto cleanup;
virshDomainSnapshotFree(snapshot2);
vshPrintExtra(ctl, _("Snapshot %s set as current"), snapshotname);
ret = true;
goto cleanup;
}
if ((current = virDomainHasCurrentSnapshot(dom, 0)) < 0)
goto cleanup;
if (!current) {
vshError(ctl, _("domain '%s' has no current snapshot"), domname);
goto cleanup;
} else {
if (!(snapshot = virDomainSnapshotCurrent(dom, 0)))
goto cleanup;
if (vshCommandOptBool(cmd, "name")) {
const char *name;
if (!(name = virDomainSnapshotGetName(snapshot)))
goto cleanup;
vshPrint(ctl, "%s", name);
} else {
if (!(xml = virDomainSnapshotGetXMLDesc(snapshot, flags)))
goto cleanup;
vshPrint(ctl, "%s", xml);
}
}
ret = true;
cleanup:
if (!ret)
virsh: use common namespacing Convert the exported items in virsh.h to use a common 'vsh' prefix. * tools/virsh.h (VIRSH_MAX_XML_FILE): Rename... (VSH_MAX_XML_FILE): ...and parenthesize. (DIFF_MSEC, CTRL_CLOSE_BRACKET): Delete. (vshUsage, vshInit, vshDeinit, vshParseArgv): Remove prototype. (editWriteToTempFile, editFile, editReadBackFile, prettyCapacity) (virshReportError): Rename... (vshEditWriteToTempFile, vshEditFile, vshEditReadBackFile) (vshPrettyCapacity, vshReportError): ...into vsh namespace. (jobWatchTimeoutFunc): Move to virsh-domain.c. * tools/virsh.c (vshCommandRun): Inline former DIFF_MSEC. (main): Inline former CTRL_CLOSE_BRACKET. (vshUsage, vshInit, vshDeinit, vshParseArgv): Make static. (prettyCapacity, virshReportError, editWriteToTempFile, editFile): Fix naming, and adjust usage. (vshAskReedit, vshCommandRun, vshEventLoop, vshInit): Adjust usage. * tools/virsh-domain.c (cmdAttachDevice, cmdCPUCompare) (cmdCPUBaseline, cmdCreate, cmdDefine, cmdDetachDevice) (cmdUpdateDevice, cmdDesc, cmdUndefine, cmdStart, cmdVcpucount) (cmdAttachDevice, cmdDomjobinfo): Likewise. * tools/virsh-edit.c (do): Likewise. * tools/virsh-interface.c (cmdInterfaceDefine): Likewise. * tools/virsh-network.c (cmdNetworkCreate, cmdNetworkDefine): Likewise. * tools/virsh-nodedev.c (cmdNodeDeviceCreate): Likewise. * tools/virsh-nwfilter.c (cmdNWFilterDefine): Likewise. * tools/virsh-pool.c (cmdPoolCreate, cmdPoolDefine) (cmdPoolDiscoverSources, cmdPoolList): Likewise. * tools/virsh-secret.c (cmdSecretDefine): Likewise. * tools/virsh-snapshot.c (cmdSnapshotCreate, vshSnapshotCreate) (vshLookupSnapshot, cmdSnapshotEdit, cmdSnapshotCurrent) (vshGetSnapshotParent): Likewise. * tools/virsh-volume.c (cmdVolCreate, cmdVolCreateFrom) (cmdVolInfo, cmdVolList): Likewise.
2012-08-19 04:10:17 +00:00
vshReportError(ctl);
VIR_FREE(xml);
virshDomainSnapshotFree(snapshot);
virshDomainFree(dom);
return ret;
}
/* Helper function to get the name of a snapshot's parent. Caller
* must free the result. Returns 0 on success (including when it was
* proven no parent exists), and -1 on failure with error reported
* (such as no snapshot support or domain deleted in meantime). */
static int
virshGetSnapshotParent(vshControl *ctl, virDomainSnapshotPtr snapshot,
char **parent_name)
{
virDomainSnapshotPtr parent = NULL;
char *xml = NULL;
xmlDocPtr xmldoc = NULL;
xmlXPathContextPtr ctxt = NULL;
int ret = -1;
virshControlPtr priv = ctl->privData;
*parent_name = NULL;
/* Try new API, since it is faster. */
if (!priv->useSnapshotOld) {
parent = virDomainSnapshotGetParent(snapshot, 0);
if (parent) {
/* API works, and virDomainSnapshotGetName will succeed */
*parent_name = vshStrdup(ctl, virDomainSnapshotGetName(parent));
ret = 0;
goto cleanup;
}
if (last_error->code == VIR_ERR_NO_DOMAIN_SNAPSHOT) {
/* API works, and we found a root with no parent */
ret = 0;
goto cleanup;
}
/* API didn't work, fall back to XML scraping. */
priv->useSnapshotOld = true;
}
xml = virDomainSnapshotGetXMLDesc(snapshot, 0);
if (!xml)
goto cleanup;
xmldoc = virXMLParseStringCtxt(xml, _("(domain_snapshot)"), &ctxt);
if (!xmldoc)
goto cleanup;
*parent_name = virXPathString("string(/domainsnapshot/parent/name)", ctxt);
ret = 0;
cleanup:
if (ret < 0) {
virsh: use common namespacing Convert the exported items in virsh.h to use a common 'vsh' prefix. * tools/virsh.h (VIRSH_MAX_XML_FILE): Rename... (VSH_MAX_XML_FILE): ...and parenthesize. (DIFF_MSEC, CTRL_CLOSE_BRACKET): Delete. (vshUsage, vshInit, vshDeinit, vshParseArgv): Remove prototype. (editWriteToTempFile, editFile, editReadBackFile, prettyCapacity) (virshReportError): Rename... (vshEditWriteToTempFile, vshEditFile, vshEditReadBackFile) (vshPrettyCapacity, vshReportError): ...into vsh namespace. (jobWatchTimeoutFunc): Move to virsh-domain.c. * tools/virsh.c (vshCommandRun): Inline former DIFF_MSEC. (main): Inline former CTRL_CLOSE_BRACKET. (vshUsage, vshInit, vshDeinit, vshParseArgv): Make static. (prettyCapacity, virshReportError, editWriteToTempFile, editFile): Fix naming, and adjust usage. (vshAskReedit, vshCommandRun, vshEventLoop, vshInit): Adjust usage. * tools/virsh-domain.c (cmdAttachDevice, cmdCPUCompare) (cmdCPUBaseline, cmdCreate, cmdDefine, cmdDetachDevice) (cmdUpdateDevice, cmdDesc, cmdUndefine, cmdStart, cmdVcpucount) (cmdAttachDevice, cmdDomjobinfo): Likewise. * tools/virsh-edit.c (do): Likewise. * tools/virsh-interface.c (cmdInterfaceDefine): Likewise. * tools/virsh-network.c (cmdNetworkCreate, cmdNetworkDefine): Likewise. * tools/virsh-nodedev.c (cmdNodeDeviceCreate): Likewise. * tools/virsh-nwfilter.c (cmdNWFilterDefine): Likewise. * tools/virsh-pool.c (cmdPoolCreate, cmdPoolDefine) (cmdPoolDiscoverSources, cmdPoolList): Likewise. * tools/virsh-secret.c (cmdSecretDefine): Likewise. * tools/virsh-snapshot.c (cmdSnapshotCreate, vshSnapshotCreate) (vshLookupSnapshot, cmdSnapshotEdit, cmdSnapshotCurrent) (vshGetSnapshotParent): Likewise. * tools/virsh-volume.c (cmdVolCreate, cmdVolCreateFrom) (cmdVolInfo, cmdVolList): Likewise.
2012-08-19 04:10:17 +00:00
vshReportError(ctl);
vshError(ctl, "%s", _("unable to determine if snapshot has parent"));
} else {
vshResetLibvirtError();
}
virshDomainSnapshotFree(parent);
xmlXPathFreeContext(ctxt);
xmlFreeDoc(xmldoc);
VIR_FREE(xml);
return ret;
}
/* Helper function to filter snapshots according to status and
* location portion of flags. Returns 0 if filter excluded snapshot,
* 1 if snapshot is okay (or if snapshot is already NULL), and -1 on
* failure, with error already reported. */
static int
virshSnapshotFilter(vshControl *ctl, virDomainSnapshotPtr snapshot,
unsigned int flags)
{
char *xml = NULL;
xmlDocPtr xmldoc = NULL;
xmlXPathContextPtr ctxt = NULL;
int ret = -1;
char *state = NULL;
if (!snapshot)
return 1;
xml = virDomainSnapshotGetXMLDesc(snapshot, 0);
if (!xml)
goto cleanup;
xmldoc = virXMLParseStringCtxt(xml, _("(domain_snapshot)"), &ctxt);
if (!xmldoc)
goto cleanup;
/* Libvirt 1.0.1 and newer never call this function, because the
* filtering is already supported by the listing functions. Older
* libvirt lacked /domainsnapshot/memory, but was also limited in
* the types of snapshots it could create: if state was disk-only,
* the snapshot is external; all other snapshots are internal. */
state = virXPathString("string(/domainsnapshot/state)", ctxt);
if (!state) {
vshError(ctl, "%s", _("unable to perform snapshot filtering"));
goto cleanup;
}
if (STREQ(state, "disk-snapshot")) {
ret = ((flags & (VIR_DOMAIN_SNAPSHOT_LIST_DISK_ONLY |
VIR_DOMAIN_SNAPSHOT_LIST_EXTERNAL)) ==
(VIR_DOMAIN_SNAPSHOT_LIST_DISK_ONLY |
VIR_DOMAIN_SNAPSHOT_LIST_EXTERNAL));
} else {
if (!(flags & VIR_DOMAIN_SNAPSHOT_LIST_INTERNAL))
ret = 0;
else if (STREQ(state, "shutoff"))
ret = !!(flags & VIR_DOMAIN_SNAPSHOT_LIST_INACTIVE);
else
ret = !!(flags & VIR_DOMAIN_SNAPSHOT_LIST_ACTIVE);
}
cleanup:
VIR_FREE(state);
xmlXPathFreeContext(ctxt);
xmlFreeDoc(xmldoc);
VIR_FREE(xml);
return ret;
}
/*
* "snapshot-info" command
*/
static const vshCmdInfo info_snapshot_info[] = {
{.name = "help",
.data = N_("snapshot information")
},
{.name = "desc",
.data = N_("Returns basic information about a snapshot.")
},
{.name = NULL}
};
static const vshCmdOptDef opts_snapshot_info[] = {
VIRSH_COMMON_OPT_DOMAIN_FULL(0),
{.name = "snapshotname",
.type = VSH_OT_STRING,
.help = N_("snapshot name"),
.completer = virshSnapshotNameCompleter,
},
VIRSH_COMMON_OPT_CURRENT(N_("info on current snapshot")),
{.name = NULL}
};
static bool
cmdSnapshotInfo(vshControl *ctl, const vshCmd *cmd)
{
virDomainPtr dom;
virDomainSnapshotPtr snapshot = NULL;
const char *name;
char *doc = NULL;
xmlDocPtr xmldoc = NULL;
xmlXPathContextPtr ctxt = NULL;
char *state = NULL;
int external;
char *parent = NULL;
bool ret = false;
int count;
unsigned int flags;
int current;
int metadata;
virshControlPtr priv = ctl->privData;
dom = virshCommandOptDomain(ctl, cmd, NULL);
if (dom == NULL)
return false;
if (virshLookupSnapshot(ctl, cmd, "snapshotname", true, dom,
&snapshot, &name) < 0)
goto cleanup;
vshPrint(ctl, "%-15s %s\n", _("Name:"), name);
vshPrint(ctl, "%-15s %s\n", _("Domain:"), virDomainGetName(dom));
/* Determine if snapshot is current; this is useful enough that we
* attempt a fallback. */
current = virDomainSnapshotIsCurrent(snapshot, 0);
if (current < 0) {
virDomainSnapshotPtr other = virDomainSnapshotCurrent(dom, 0);
vshResetLibvirtError();
current = 0;
if (other) {
if (STREQ(name, virDomainSnapshotGetName(other)))
current = 1;
virshDomainSnapshotFree(other);
}
}
vshPrint(ctl, "%-15s %s\n", _("Current:"),
current > 0 ? _("yes") : _("no"));
/* Get the XML configuration of the snapshot to determine the
* state of the machine at the time of the snapshot. */
doc = virDomainSnapshotGetXMLDesc(snapshot, 0);
if (!doc)
goto cleanup;
xmldoc = virXMLParseStringCtxt(doc, _("(domain_snapshot)"), &ctxt);
if (!xmldoc)
goto cleanup;
state = virXPathString("string(/domainsnapshot/state)", ctxt);
if (!state) {
vshError(ctl, "%s",
_("unexpected problem reading snapshot xml"));
goto cleanup;
}
vshPrint(ctl, "%-15s %s\n", _("State:"), state);
/* In addition to state, location is useful. If the snapshot has
* a <memory> element, then the existence of snapshot='external'
* prior to <domain> is the deciding factor; for snapshots
* created prior to 1.0.1, a state of disk-only is the only
* external snapshot. */
switch (virXPathBoolean("boolean(/domainsnapshot/memory)", ctxt)) {
case 1:
external = virXPathBoolean("boolean(/domainsnapshot/memory[@snapshot='external'] "
"| /domainsnapshot/disks/disk[@snapshot='external'])",
ctxt);
break;
case 0:
external = STREQ(state, "disk-snapshot");
break;
default:
external = -1;
break;
}
if (external < 0) {
vshError(ctl, "%s",
_("unexpected problem reading snapshot xml"));
goto cleanup;
}
vshPrint(ctl, "%-15s %s\n", _("Location:"),
external ? _("external") : _("internal"));
/* Since we already have the XML, there's no need to call
* virDomainSnapshotGetParent */
parent = virXPathString("string(/domainsnapshot/parent/name)", ctxt);
vshPrint(ctl, "%-15s %s\n", _("Parent:"), NULLSTR_MINUS(parent));
/* Children, Descendants. After this point, the fallback to
* compute children is too expensive, so we gracefully quit if the
* APIs don't exist. */
if (priv->useSnapshotOld) {
ret = true;
goto cleanup;
}
flags = 0;
count = virDomainSnapshotNumChildren(snapshot, flags);
if (count < 0) {
if (last_error->code == VIR_ERR_NO_SUPPORT) {
vshResetLibvirtError();
ret = true;
}
goto cleanup;
}
vshPrint(ctl, "%-15s %d\n", _("Children:"), count);
flags = VIR_DOMAIN_SNAPSHOT_LIST_DESCENDANTS;
count = virDomainSnapshotNumChildren(snapshot, flags);
if (count < 0)
goto cleanup;
vshPrint(ctl, "%-15s %d\n", _("Descendants:"), count);
/* Metadata; the fallback here relies on the fact that metadata
* used to have an all-or-nothing effect on snapshot count. */
metadata = virDomainSnapshotHasMetadata(snapshot, 0);
if (metadata < 0) {
metadata = virDomainSnapshotNum(dom,
VIR_DOMAIN_SNAPSHOT_LIST_METADATA);
vshResetLibvirtError();
}
if (metadata >= 0)
vshPrint(ctl, "%-15s %s\n", _("Metadata:"),
metadata ? _("yes") : _("no"));
ret = true;
cleanup:
VIR_FREE(state);
xmlXPathFreeContext(ctxt);
xmlFreeDoc(xmldoc);
VIR_FREE(doc);
VIR_FREE(parent);
virshDomainSnapshotFree(snapshot);
virshDomainFree(dom);
return ret;
}
/* Helpers for collecting a list of snapshots. */
struct virshSnap {
virDomainSnapshotPtr snap;
char *parent;
};
struct virshSnapshotList {
struct virshSnap *snaps;
int nsnaps;
};
typedef struct virshSnapshotList *virshSnapshotListPtr;
static void
virshSnapshotListFree(virshSnapshotListPtr snaplist)
{
size_t i;
if (!snaplist)
return;
if (snaplist->snaps) {
for (i = 0; i < snaplist->nsnaps; i++) {
virshDomainSnapshotFree(snaplist->snaps[i].snap);
VIR_FREE(snaplist->snaps[i].parent);
}
VIR_FREE(snaplist->snaps);
}
VIR_FREE(snaplist);
}
static int
virshSnapSorter(const void *a, const void *b)
{
const struct virshSnap *sa = a;
const struct virshSnap *sb = b;
if (sa->snap && !sb->snap)
return -1;
if (!sa->snap)
return sb->snap != NULL;
return vshStrcasecmp(virDomainSnapshotGetName(sa->snap),
virDomainSnapshotGetName(sb->snap));
}
/* Compute a list of snapshots from DOM. If FROM is provided, the
* list is limited to descendants of the given snapshot. If FLAGS is
* given, the list is filtered. If TREE is specified, then all but
* FROM or the roots will also have parent information. */
static virshSnapshotListPtr
virshSnapshotListCollect(vshControl *ctl, virDomainPtr dom,
virDomainSnapshotPtr from,
unsigned int orig_flags, bool tree)
{
size_t i;
char **names = NULL;
int count = -1;
bool descendants = false;
bool roots = false;
virDomainSnapshotPtr *snaps;
virshSnapshotListPtr snaplist = vshMalloc(ctl, sizeof(*snaplist));
virshSnapshotListPtr ret = NULL;
const char *fromname = NULL;
int start_index = -1;
int deleted = 0;
bool filter_fallback = false;
unsigned int flags = orig_flags;
virshControlPtr priv = ctl->privData;
/* Try the interface available in 0.9.13 and newer. */
if (!priv->useSnapshotOld) {
if (from)
count = virDomainSnapshotListAllChildren(from, &snaps, flags);
else
count = virDomainListAllSnapshots(dom, &snaps, flags);
/* If we failed because of flags added in 1.0.1, we can do
* fallback filtering. */
if (count < 0 && last_error->code == VIR_ERR_INVALID_ARG &&
flags & (VIR_DOMAIN_SNAPSHOT_FILTERS_STATUS |
VIR_DOMAIN_SNAPSHOT_FILTERS_LOCATION)) {
flags &= ~(VIR_DOMAIN_SNAPSHOT_FILTERS_STATUS |
VIR_DOMAIN_SNAPSHOT_FILTERS_LOCATION);
vshResetLibvirtError();
filter_fallback = true;
if (from)
count = virDomainSnapshotListAllChildren(from, &snaps, flags);
else
count = virDomainListAllSnapshots(dom, &snaps, flags);
}
}
if (count >= 0) {
/* When mixing --from and --tree, we also want a copy of from
* in the list, but with no parent for that one entry. */
snaplist->snaps = vshCalloc(ctl, count + (tree && from),
sizeof(*snaplist->snaps));
snaplist->nsnaps = count;
for (i = 0; i < count; i++)
snaplist->snaps[i].snap = snaps[i];
VIR_FREE(snaps);
if (tree) {
for (i = 0; i < count; i++) {
if (virshGetSnapshotParent(ctl, snaplist->snaps[i].snap,
&snaplist->snaps[i].parent) < 0)
goto cleanup;
}
if (from) {
snaplist->snaps[snaplist->nsnaps++].snap = from;
virDomainSnapshotRef(from);
}
}
goto success;
}
/* Assume that if we got this far, then the --no-leaves and
* --no-metadata flags were not supported. Disable groups that
* have no impact. */
/* XXX should we emulate --no-leaves? */
if (flags & VIR_DOMAIN_SNAPSHOT_LIST_NO_LEAVES &&
flags & VIR_DOMAIN_SNAPSHOT_LIST_LEAVES)
flags &= ~(VIR_DOMAIN_SNAPSHOT_LIST_NO_LEAVES |
VIR_DOMAIN_SNAPSHOT_LIST_LEAVES);
if (flags & VIR_DOMAIN_SNAPSHOT_LIST_NO_METADATA &&
flags & VIR_DOMAIN_SNAPSHOT_LIST_METADATA)
flags &= ~(VIR_DOMAIN_SNAPSHOT_LIST_NO_METADATA |
VIR_DOMAIN_SNAPSHOT_LIST_METADATA);
if (flags & VIR_DOMAIN_SNAPSHOT_LIST_NO_METADATA) {
/* We can emulate --no-metadata if --metadata was supported,
* since it was an all-or-none attribute on old servers. */
count = virDomainSnapshotNum(dom,
VIR_DOMAIN_SNAPSHOT_LIST_METADATA);
if (count < 0)
goto cleanup;
if (count > 0)
return snaplist;
flags &= ~VIR_DOMAIN_SNAPSHOT_LIST_NO_METADATA;
}
if (flags & (VIR_DOMAIN_SNAPSHOT_FILTERS_STATUS |
VIR_DOMAIN_SNAPSHOT_FILTERS_LOCATION)) {
flags &= ~(VIR_DOMAIN_SNAPSHOT_FILTERS_STATUS |
VIR_DOMAIN_SNAPSHOT_FILTERS_LOCATION);
filter_fallback = true;
}
/* This uses the interfaces available in 0.8.0-0.9.6
* (virDomainSnapshotListNames, global list only) and in
* 0.9.7-0.9.12 (addition of virDomainSnapshotListChildrenNames
* for child listing, and new flags), as follows, with [*] by the
* combinations that need parent info (either for filtering
* purposes or for the resulting tree listing):
* old new
* list global as-is global as-is
* list --roots *global + filter global + flags
* list --from *global + filter child as-is
* list --from --descendants *global + filter child + flags
* list --tree *global as-is *global as-is
* list --tree --from *global + filter *child + flags
*
* Additionally, when --tree and --from are both used, from is
* added to the final list as the only element without a parent.
* Otherwise, --from does not appear in the final list.
*/
if (from) {
fromname = virDomainSnapshotGetName(from);
if (!fromname) {
vshError(ctl, "%s", _("Could not get snapshot name"));
goto cleanup;
}
descendants = (flags & VIR_DOMAIN_SNAPSHOT_LIST_DESCENDANTS) || tree;
if (tree)
flags |= VIR_DOMAIN_SNAPSHOT_LIST_DESCENDANTS;
/* Determine if we can use the new child listing API. */
if (priv->useSnapshotOld ||
((count = virDomainSnapshotNumChildren(from, flags)) < 0 &&
last_error->code == VIR_ERR_NO_SUPPORT)) {
/* We can emulate --from. */
/* XXX can we also emulate --leaves? */
vshResetLibvirtError();
priv->useSnapshotOld = true;
flags &= ~VIR_DOMAIN_SNAPSHOT_LIST_DESCENDANTS;
goto global;
}
if (tree && count >= 0)
count++;
} else {
global:
/* Global listing (including fallback when --from failed with
* child listing). */
count = virDomainSnapshotNum(dom, flags);
/* Fall back to simulation if --roots was unsupported. */
/* XXX can we also emulate --leaves? */
if (!from && count < 0 && last_error->code == VIR_ERR_INVALID_ARG &&
(flags & VIR_DOMAIN_SNAPSHOT_LIST_ROOTS)) {
vshResetLibvirtError();
roots = true;
flags &= ~VIR_DOMAIN_SNAPSHOT_LIST_ROOTS;
count = virDomainSnapshotNum(dom, flags);
}
}
if (count < 0) {
if (!last_error)
vshError(ctl, _("failed to collect snapshot list"));
goto cleanup;
}
if (!count)
goto success;
names = vshCalloc(ctl, sizeof(*names), count);
/* Now that we have a count, collect the list. */
if (from && !priv->useSnapshotOld) {
if (tree) {
count = virDomainSnapshotListChildrenNames(from, names + 1,
count - 1, flags);
if (count >= 0) {
count++;
names[0] = vshStrdup(ctl, fromname);
}
} else {
count = virDomainSnapshotListChildrenNames(from, names,
count, flags);
}
} else {
count = virDomainSnapshotListNames(dom, names, count, flags);
}
if (count < 0)
goto cleanup;
snaplist->snaps = vshCalloc(ctl, sizeof(*snaplist->snaps), count);
snaplist->nsnaps = count;
for (i = 0; i < count; i++) {
snaplist->snaps[i].snap = virDomainSnapshotLookupByName(dom,
names[i], 0);
if (!snaplist->snaps[i].snap)
goto cleanup;
}
/* Collect parents when needed. With the new API, --tree and
* --from together put from as the first element without a parent;
* with the old API we still need to do a post-process filtering
* based on all parent information. */
if (tree || (from && priv->useSnapshotOld) || roots) {
for (i = (from && !priv->useSnapshotOld); i < count; i++) {
if (from && priv->useSnapshotOld && STREQ(names[i], fromname)) {
start_index = i;
if (tree)
continue;
}
if (virshGetSnapshotParent(ctl, snaplist->snaps[i].snap,
&snaplist->snaps[i].parent) < 0)
goto cleanup;
if ((from && ((tree && !snaplist->snaps[i].parent) ||
(!descendants &&
STRNEQ_NULLABLE(fromname,
snaplist->snaps[i].parent)))) ||
(roots && snaplist->snaps[i].parent)) {
virshDomainSnapshotFree(snaplist->snaps[i].snap);
snaplist->snaps[i].snap = NULL;
VIR_FREE(snaplist->snaps[i].parent);
deleted++;
}
}
}
if (tree)
goto success;
if (priv->useSnapshotOld && descendants) {
bool changed = false;
bool remaining = false;
/* Make multiple passes over the list - first pass finds
* direct children and NULLs out all roots and from, remaining
* passes NULL out any undecided entry whose parent is not
* still in list. We mark known descendants by clearing
* snaps[i].parents. Sorry, this is O(n^3) - hope your
* hierarchy isn't huge. XXX Is it worth making O(n^2 log n)
* by using qsort and bsearch? */
if (start_index < 0) {
vshError(ctl, _("snapshot %s disappeared from list"), fromname);
goto cleanup;
}
for (i = 0; i < count; i++) {
if (i == start_index || !snaplist->snaps[i].parent) {
VIR_FREE(names[i]);
virshDomainSnapshotFree(snaplist->snaps[i].snap);
snaplist->snaps[i].snap = NULL;
VIR_FREE(snaplist->snaps[i].parent);
deleted++;
} else if (STREQ(snaplist->snaps[i].parent, fromname)) {
VIR_FREE(snaplist->snaps[i].parent);
changed = true;
} else {
remaining = true;
}
}
if (!changed) {
ret = vshMalloc(ctl, sizeof(*snaplist));
goto cleanup;
}
while (changed && remaining) {
changed = remaining = false;
for (i = 0; i < count; i++) {
bool found_parent = false;
size_t j;
if (!names[i] || !snaplist->snaps[i].parent)
continue;
for (j = 0; j < count; j++) {
if (!names[j] || i == j)
continue;
if (STREQ(snaplist->snaps[i].parent, names[j])) {
found_parent = true;
if (!snaplist->snaps[j].parent)
VIR_FREE(snaplist->snaps[i].parent);
else
remaining = true;
break;
}
}
if (!found_parent) {
changed = true;
VIR_FREE(names[i]);
virshDomainSnapshotFree(snaplist->snaps[i].snap);
snaplist->snaps[i].snap = NULL;
VIR_FREE(snaplist->snaps[i].parent);
deleted++;
}
}
}
}
success:
if (filter_fallback) {
/* Older API didn't filter on status or location, but the
* information is available in domain XML. */
if (!(orig_flags & VIR_DOMAIN_SNAPSHOT_FILTERS_STATUS))
orig_flags |= VIR_DOMAIN_SNAPSHOT_FILTERS_STATUS;
if (!(orig_flags & VIR_DOMAIN_SNAPSHOT_FILTERS_LOCATION))
orig_flags |= VIR_DOMAIN_SNAPSHOT_FILTERS_LOCATION;
for (i = 0; i < snaplist->nsnaps; i++) {
switch (virshSnapshotFilter(ctl, snaplist->snaps[i].snap,
orig_flags)) {
case 1:
break;
case 0:
virshDomainSnapshotFree(snaplist->snaps[i].snap);
snaplist->snaps[i].snap = NULL;
VIR_FREE(snaplist->snaps[i].parent);
deleted++;
break;
default:
goto cleanup;
}
}
}
virsh: Add snapshot-list --topological For snapshots, virsh already has a (shockingly naive [1]) client-side topological sorter with the --tree option. But as a series of REDEFINE calls must be presented in topological order, it's worth letting the server do the work for us, especially since the server can give us a topological sorting with less effort than our naive client reconstruction. [1] The XXX comment in virshSnapshotListCollect() about --tree being O(n^3) is telling; https://en.wikipedia.org/wiki/Topological_sorting is an interesting resource describing Kahn's algorithm and other approaches for O(n) topological sorting for anyone motivated to use a more elegant algorithm than brute force - but that doesn't affect this patch. For now, I am purposefully NOT implementing virsh fallback code to provide a topological sort when the flag was rejected as unsupported; we can worry about that down the road if users actually demonstrate that they use new virsh but old libvirt to even need the fallback. (The code we use for --tree could be repurposed to be such a fallback, whether or not we keep it naive or improve it to be faster - but again, no one should spend time on a fallback without evidence that we need it.) The test driver makes it easy to test: $ virsh -c test:///default ' snapshot-create-as test a snapshot-create-as test c snapshot-create-as test b snapshot-list test snapshot-list test --topological snapshot-list test --descendants a snapshot-list test --descendants a --topological snapshot-list test --tree snapshot-list test --tree --topological ' Without any flags, virsh does client-side sorting alphabetically, and lists 'b' before 'c' (even though 'c' is the parent of 'b'); with the flag, virsh skips sorting, and you can now see that the server handed back data in a correct ordering. As shown here with a simple linear chain, there isn't any other possible ordering, so --tree mode doesn't seem to care whether --topological is used. But it is possible to compose more complicated DAGs with multiple children to a parent (representing reverting back to a snapshot then creating more snapshots along those divergent execution timelines), where it is then possible (but not guaranteed) that adding the --topological flag changes the --tree output (the client-side --tree algorithm breaks ties based on alphabetical sorting between two nodes that share the same parent, while the --topological sort skips the client-side alphabetical sort and ends up exposing the server's internal order for siblings, whether that be historical creation order or dependent on a random hash seed). But even if the results differ, they will still be topologically correct. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com> Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2019-03-08 04:12:01 +00:00
if (!(orig_flags & VIR_DOMAIN_SNAPSHOT_LIST_TOPOLOGICAL))
qsort(snaplist->snaps, snaplist->nsnaps, sizeof(*snaplist->snaps),
virshSnapSorter);
snaplist->nsnaps -= deleted;
VIR_STEAL_PTR(ret, snaplist);
cleanup:
virshSnapshotListFree(snaplist);
if (names && count > 0)
for (i = 0; i < count; i++)
VIR_FREE(names[i]);
VIR_FREE(names);
return ret;
}
static const char *
virshSnapshotListLookup(int id, bool parent, void *opaque)
{
virshSnapshotListPtr snaplist = opaque;
if (parent)
return snaplist->snaps[id].parent;
return virDomainSnapshotGetName(snaplist->snaps[id].snap);
}
/*
* "snapshot-list" command
*/
static const vshCmdInfo info_snapshot_list[] = {
{.name = "help",
.data = N_("List snapshots for a domain")
},
{.name = "desc",
.data = N_("Snapshot List")
},
{.name = NULL}
};
static const vshCmdOptDef opts_snapshot_list[] = {
VIRSH_COMMON_OPT_DOMAIN_FULL(0),
{.name = "parent",
.type = VSH_OT_BOOL,
.help = N_("add a column showing parent snapshot")
},
{.name = "roots",
.type = VSH_OT_BOOL,
.help = N_("list only snapshots without parents")
},
{.name = "leaves",
.type = VSH_OT_BOOL,
.help = N_("list only snapshots without children")
},
{.name = "no-leaves",
.type = VSH_OT_BOOL,
.help = N_("list only snapshots that are not leaves (with children)")
},
{.name = "metadata",
.type = VSH_OT_BOOL,
.help = N_("list only snapshots that have metadata that would prevent undefine")
},
{.name = "no-metadata",
.type = VSH_OT_BOOL,
.help = N_("list only snapshots that have no metadata managed by libvirt")
},
{.name = "inactive",
.type = VSH_OT_BOOL,
.help = N_("filter by snapshots taken while inactive")
},
{.name = "active",
.type = VSH_OT_BOOL,
.help = N_("filter by snapshots taken while active (full system snapshots)")
},
{.name = "disk-only",
.type = VSH_OT_BOOL,
.help = N_("filter by disk-only snapshots")
},
{.name = "internal",
.type = VSH_OT_BOOL,
.help = N_("filter by internal snapshots")
},
{.name = "external",
.type = VSH_OT_BOOL,
.help = N_("filter by external snapshots")
},
{.name = "tree",
.type = VSH_OT_BOOL,
.help = N_("list snapshots in a tree")
},
{.name = "from",
.type = VSH_OT_STRING,
.help = N_("limit list to children of given snapshot")
},
VIRSH_COMMON_OPT_CURRENT(N_("limit list to children of current snapshot")),
{.name = "descendants",
.type = VSH_OT_BOOL,
.help = N_("with --from, list all descendants")
},
{.name = "name",
.type = VSH_OT_BOOL,
.help = N_("list snapshot names only")
},
virsh: Add snapshot-list --topological For snapshots, virsh already has a (shockingly naive [1]) client-side topological sorter with the --tree option. But as a series of REDEFINE calls must be presented in topological order, it's worth letting the server do the work for us, especially since the server can give us a topological sorting with less effort than our naive client reconstruction. [1] The XXX comment in virshSnapshotListCollect() about --tree being O(n^3) is telling; https://en.wikipedia.org/wiki/Topological_sorting is an interesting resource describing Kahn's algorithm and other approaches for O(n) topological sorting for anyone motivated to use a more elegant algorithm than brute force - but that doesn't affect this patch. For now, I am purposefully NOT implementing virsh fallback code to provide a topological sort when the flag was rejected as unsupported; we can worry about that down the road if users actually demonstrate that they use new virsh but old libvirt to even need the fallback. (The code we use for --tree could be repurposed to be such a fallback, whether or not we keep it naive or improve it to be faster - but again, no one should spend time on a fallback without evidence that we need it.) The test driver makes it easy to test: $ virsh -c test:///default ' snapshot-create-as test a snapshot-create-as test c snapshot-create-as test b snapshot-list test snapshot-list test --topological snapshot-list test --descendants a snapshot-list test --descendants a --topological snapshot-list test --tree snapshot-list test --tree --topological ' Without any flags, virsh does client-side sorting alphabetically, and lists 'b' before 'c' (even though 'c' is the parent of 'b'); with the flag, virsh skips sorting, and you can now see that the server handed back data in a correct ordering. As shown here with a simple linear chain, there isn't any other possible ordering, so --tree mode doesn't seem to care whether --topological is used. But it is possible to compose more complicated DAGs with multiple children to a parent (representing reverting back to a snapshot then creating more snapshots along those divergent execution timelines), where it is then possible (but not guaranteed) that adding the --topological flag changes the --tree output (the client-side --tree algorithm breaks ties based on alphabetical sorting between two nodes that share the same parent, while the --topological sort skips the client-side alphabetical sort and ends up exposing the server's internal order for siblings, whether that be historical creation order or dependent on a random hash seed). But even if the results differ, they will still be topologically correct. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com> Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2019-03-08 04:12:01 +00:00
{.name = "topological",
.type = VSH_OT_BOOL,
.help = N_("sort list topologically rather than by name"),
},
{.name = NULL}
};
static bool
cmdSnapshotList(vshControl *ctl, const vshCmd *cmd)
{
virDomainPtr dom = NULL;
bool ret = false;
unsigned int flags = 0;
size_t i;
xmlDocPtr xml = NULL;
xmlXPathContextPtr ctxt = NULL;
char *doc = NULL;
virDomainSnapshotPtr snapshot = NULL;
char *state = NULL;
long long creation_longlong;
time_t creation_time_t;
char timestr[100];
struct tm time_info;
bool tree = vshCommandOptBool(cmd, "tree");
bool name = vshCommandOptBool(cmd, "name");
bool from = vshCommandOptBool(cmd, "from");
bool parent = vshCommandOptBool(cmd, "parent");
bool roots = vshCommandOptBool(cmd, "roots");
bool current = vshCommandOptBool(cmd, "current");
const char *from_snap = NULL;
char *parent_snap = NULL;
virDomainSnapshotPtr start = NULL;
virshSnapshotListPtr snaplist = NULL;
vshTablePtr table = NULL;
VSH_EXCLUSIVE_OPTIONS_VAR(tree, name);
VSH_EXCLUSIVE_OPTIONS_VAR(parent, roots);
VSH_EXCLUSIVE_OPTIONS_VAR(parent, tree);
VSH_EXCLUSIVE_OPTIONS_VAR(roots, tree);
VSH_EXCLUSIVE_OPTIONS_VAR(roots, from);
VSH_EXCLUSIVE_OPTIONS_VAR(roots, current);
#define FILTER(option, flag) \
do { \
if (vshCommandOptBool(cmd, option)) { \
if (tree) { \
vshError(ctl, \
_("--%s and --tree are mutually exclusive"), \
option); \
return false; \
} \
flags |= VIR_DOMAIN_SNAPSHOT_LIST_ ## flag; \
} \
} while (0)
FILTER("leaves", LEAVES);
FILTER("no-leaves", NO_LEAVES);
FILTER("inactive", INACTIVE);
FILTER("active", ACTIVE);
FILTER("disk-only", DISK_ONLY);
FILTER("internal", INTERNAL);
FILTER("external", EXTERNAL);
#undef FILTER
virsh: Add snapshot-list --topological For snapshots, virsh already has a (shockingly naive [1]) client-side topological sorter with the --tree option. But as a series of REDEFINE calls must be presented in topological order, it's worth letting the server do the work for us, especially since the server can give us a topological sorting with less effort than our naive client reconstruction. [1] The XXX comment in virshSnapshotListCollect() about --tree being O(n^3) is telling; https://en.wikipedia.org/wiki/Topological_sorting is an interesting resource describing Kahn's algorithm and other approaches for O(n) topological sorting for anyone motivated to use a more elegant algorithm than brute force - but that doesn't affect this patch. For now, I am purposefully NOT implementing virsh fallback code to provide a topological sort when the flag was rejected as unsupported; we can worry about that down the road if users actually demonstrate that they use new virsh but old libvirt to even need the fallback. (The code we use for --tree could be repurposed to be such a fallback, whether or not we keep it naive or improve it to be faster - but again, no one should spend time on a fallback without evidence that we need it.) The test driver makes it easy to test: $ virsh -c test:///default ' snapshot-create-as test a snapshot-create-as test c snapshot-create-as test b snapshot-list test snapshot-list test --topological snapshot-list test --descendants a snapshot-list test --descendants a --topological snapshot-list test --tree snapshot-list test --tree --topological ' Without any flags, virsh does client-side sorting alphabetically, and lists 'b' before 'c' (even though 'c' is the parent of 'b'); with the flag, virsh skips sorting, and you can now see that the server handed back data in a correct ordering. As shown here with a simple linear chain, there isn't any other possible ordering, so --tree mode doesn't seem to care whether --topological is used. But it is possible to compose more complicated DAGs with multiple children to a parent (representing reverting back to a snapshot then creating more snapshots along those divergent execution timelines), where it is then possible (but not guaranteed) that adding the --topological flag changes the --tree output (the client-side --tree algorithm breaks ties based on alphabetical sorting between two nodes that share the same parent, while the --topological sort skips the client-side alphabetical sort and ends up exposing the server's internal order for siblings, whether that be historical creation order or dependent on a random hash seed). But even if the results differ, they will still be topologically correct. Signed-off-by: Eric Blake <eblake@redhat.com> Reviewed-by: Ján Tomko <jtomko@redhat.com> Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
2019-03-08 04:12:01 +00:00
if (vshCommandOptBool(cmd, "topological"))
flags |= VIR_DOMAIN_SNAPSHOT_LIST_TOPOLOGICAL;
if (roots)
flags |= VIR_DOMAIN_SNAPSHOT_LIST_ROOTS;
if (vshCommandOptBool(cmd, "metadata"))
flags |= VIR_DOMAIN_SNAPSHOT_LIST_METADATA;
if (vshCommandOptBool(cmd, "no-metadata"))
flags |= VIR_DOMAIN_SNAPSHOT_LIST_NO_METADATA;
if (vshCommandOptBool(cmd, "descendants")) {
if (!from && !current) {
vshError(ctl, "%s",
_("--descendants requires either --from or --current"));
return false;
}
flags |= VIR_DOMAIN_SNAPSHOT_LIST_DESCENDANTS;
}
if (!(dom = virshCommandOptDomain(ctl, cmd, NULL)))
return false;
if ((from || current) &&
virshLookupSnapshot(ctl, cmd, "from", true, dom, &start, &from_snap) < 0)
goto cleanup;
if (!(snaplist = virshSnapshotListCollect(ctl, dom, start, flags, tree)))
goto cleanup;
if (!tree && !name) {
if (parent)
table = vshTableNew(_("Name"), _("Creation Time"), _("State"), _("Parent"), NULL);
else
table = vshTableNew(_("Name"), _("Creation Time"), _("State"), NULL);
if (!table)
goto cleanup;
}
if (tree) {
for (i = 0; i < snaplist->nsnaps; i++) {
if (!snaplist->snaps[i].parent &&
vshTreePrint(ctl, virshSnapshotListLookup, snaplist,
snaplist->nsnaps, i) < 0)
goto cleanup;
}
ret = true;
goto cleanup;
}
for (i = 0; i < snaplist->nsnaps; i++) {
const char *snap_name;
/* free up memory from previous iterations of the loop */
VIR_FREE(parent_snap);
VIR_FREE(state);
xmlXPathFreeContext(ctxt);
xmlFreeDoc(xml);
VIR_FREE(doc);
snapshot = snaplist->snaps[i].snap;
snap_name = virDomainSnapshotGetName(snapshot);
assert(snap_name);
if (name) {
/* just print the snapshot name */
vshPrint(ctl, "%s\n", snap_name);
continue;
}
if (!(doc = virDomainSnapshotGetXMLDesc(snapshot, 0)))
continue;
if (!(xml = virXMLParseStringCtxt(doc, _("(domain_snapshot)"), &ctxt)))
continue;
if (parent)
parent_snap = virXPathString("string(/domainsnapshot/parent/name)",
ctxt);
if (!(state = virXPathString("string(/domainsnapshot/state)", ctxt)))
continue;
if (virXPathLongLong("string(/domainsnapshot/creationTime)", ctxt,
&creation_longlong) < 0)
continue;
creation_time_t = creation_longlong;
if (creation_time_t != creation_longlong) {
vshError(ctl, "%s", _("time_t overflow"));
continue;
}
localtime_r(&creation_time_t, &time_info);
strftime(timestr, sizeof(timestr), "%Y-%m-%d %H:%M:%S %z",
&time_info);
if (parent) {
if (vshTableRowAppend(table, snap_name, timestr, state,
NULLSTR_EMPTY(parent_snap),
NULL) < 0)
goto cleanup;
} else {
if (vshTableRowAppend(table, snap_name, timestr, state,
NULL) < 0)
goto cleanup;
}
}
if (table)
vshTablePrintToStdout(table, ctl);
ret = true;
cleanup:
/* this frees up memory from the last iteration of the loop */
virshSnapshotListFree(snaplist);
VIR_FREE(parent_snap);
VIR_FREE(state);
virshDomainSnapshotFree(start);
xmlXPathFreeContext(ctxt);
xmlFreeDoc(xml);
VIR_FREE(doc);
virshDomainFree(dom);
vshTableFree(table);
return ret;
}
/*
* "snapshot-dumpxml" command
*/
static const vshCmdInfo info_snapshot_dumpxml[] = {
{.name = "help",
.data = N_("Dump XML for a domain snapshot")
},
{.name = "desc",
.data = N_("Snapshot Dump XML")
},
{.name = NULL}
};
static const vshCmdOptDef opts_snapshot_dumpxml[] = {
VIRSH_COMMON_OPT_DOMAIN_FULL(0),
{.name = "snapshotname",
.type = VSH_OT_DATA,
.flags = VSH_OFLAG_REQ,
.help = N_("snapshot name"),
.completer = virshSnapshotNameCompleter,
},
{.name = "security-info",
.type = VSH_OT_BOOL,
.help = N_("include security sensitive information in XML dump")
},
{.name = NULL}
};
static bool
cmdSnapshotDumpXML(vshControl *ctl, const vshCmd *cmd)
{
virDomainPtr dom = NULL;
bool ret = false;
const char *name = NULL;
virDomainSnapshotPtr snapshot = NULL;
char *xml = NULL;
unsigned int flags = 0;
if (vshCommandOptBool(cmd, "security-info"))
flags |= VIR_DOMAIN_XML_SECURE;
if (vshCommandOptStringReq(ctl, cmd, "snapshotname", &name) < 0)
return false;
if (!(dom = virshCommandOptDomain(ctl, cmd, NULL)))
return false;
if (!(snapshot = virDomainSnapshotLookupByName(dom, name, 0)))
goto cleanup;
if (!(xml = virDomainSnapshotGetXMLDesc(snapshot, flags)))
goto cleanup;
vshPrint(ctl, "%s", xml);
ret = true;
cleanup:
VIR_FREE(xml);
virshDomainSnapshotFree(snapshot);
virshDomainFree(dom);
return ret;
}
/*
* "snapshot-parent" command
*/
static const vshCmdInfo info_snapshot_parent[] = {
{.name = "help",
.data = N_("Get the name of the parent of a snapshot")
},
{.name = "desc",
.data = N_("Extract the snapshot's parent, if any")
},
{.name = NULL}
};
static const vshCmdOptDef opts_snapshot_parent[] = {
VIRSH_COMMON_OPT_DOMAIN_FULL(0),
{.name = "snapshotname",
.type = VSH_OT_STRING,
.help = N_("find parent of snapshot name"),
.completer = virshSnapshotNameCompleter,
},
VIRSH_COMMON_OPT_CURRENT(N_("find parent of current snapshot")),
{.name = NULL}
};
static bool
cmdSnapshotParent(vshControl *ctl, const vshCmd *cmd)
{
virDomainPtr dom = NULL;
bool ret = false;
const char *name = NULL;
virDomainSnapshotPtr snapshot = NULL;
char *parent = NULL;
dom = virshCommandOptDomain(ctl, cmd, NULL);
if (dom == NULL)
goto cleanup;
if (virshLookupSnapshot(ctl, cmd, "snapshotname", true, dom,
&snapshot, &name) < 0)
goto cleanup;
if (virshGetSnapshotParent(ctl, snapshot, &parent) < 0)
goto cleanup;
if (!parent) {
vshError(ctl, _("snapshot '%s' has no parent"), name);
goto cleanup;
}
vshPrint(ctl, "%s", parent);
ret = true;
cleanup:
VIR_FREE(parent);
virshDomainSnapshotFree(snapshot);
virshDomainFree(dom);
return ret;
}
/*
* "snapshot-revert" command
*/
static const vshCmdInfo info_snapshot_revert[] = {
{.name = "help",
.data = N_("Revert a domain to a snapshot")
},
{.name = "desc",
.data = N_("Revert domain to snapshot")
},
{.name = NULL}
};
static const vshCmdOptDef opts_snapshot_revert[] = {
VIRSH_COMMON_OPT_DOMAIN_FULL(0),
{.name = "snapshotname",
.type = VSH_OT_STRING,
.help = N_("snapshot name"),
.completer = virshSnapshotNameCompleter,
},
VIRSH_COMMON_OPT_CURRENT(N_("revert to current snapshot")),
{.name = "running",
.type = VSH_OT_BOOL,
.help = N_("after reverting, change state to running")
},
{.name = "paused",
.type = VSH_OT_BOOL,
.help = N_("after reverting, change state to paused")
},
{.name = "force",
.type = VSH_OT_BOOL,
.help = N_("try harder on risky reverts")
},
{.name = NULL}
};
static bool
cmdDomainSnapshotRevert(vshControl *ctl, const vshCmd *cmd)
{
virDomainPtr dom = NULL;
bool ret = false;
const char *name = NULL;
virDomainSnapshotPtr snapshot = NULL;
unsigned int flags = 0;
bool force = false;
int result;
if (vshCommandOptBool(cmd, "running"))
flags |= VIR_DOMAIN_SNAPSHOT_REVERT_RUNNING;
if (vshCommandOptBool(cmd, "paused"))
flags |= VIR_DOMAIN_SNAPSHOT_REVERT_PAUSED;
/* We want virsh snapshot-revert --force to work even when talking
* to older servers that did the unsafe revert by default but
* reject the flag, so we probe without the flag, and only use it
* when the error says it will make a difference. */
if (vshCommandOptBool(cmd, "force"))
force = true;
dom = virshCommandOptDomain(ctl, cmd, NULL);
if (dom == NULL)
goto cleanup;
if (virshLookupSnapshot(ctl, cmd, "snapshotname", true, dom,
&snapshot, &name) < 0)
goto cleanup;
result = virDomainRevertToSnapshot(snapshot, flags);
if (result < 0 && force &&
last_error->code == VIR_ERR_SNAPSHOT_REVERT_RISKY) {
flags |= VIR_DOMAIN_SNAPSHOT_REVERT_FORCE;
vshResetLibvirtError();
result = virDomainRevertToSnapshot(snapshot, flags);
}
if (result < 0)
goto cleanup;
ret = true;
cleanup:
virshDomainSnapshotFree(snapshot);
virshDomainFree(dom);
return ret;
}
/*
* "snapshot-delete" command
*/
static const vshCmdInfo info_snapshot_delete[] = {
{.name = "help",
.data = N_("Delete a domain snapshot")
},
{.name = "desc",
.data = N_("Snapshot Delete")
},
{.name = NULL}
};
static const vshCmdOptDef opts_snapshot_delete[] = {
VIRSH_COMMON_OPT_DOMAIN_FULL(0),
{.name = "snapshotname",
.type = VSH_OT_STRING,
.help = N_("snapshot name"),
.completer = virshSnapshotNameCompleter,
},
VIRSH_COMMON_OPT_CURRENT(N_("delete current snapshot")),
{.name = "children",
.type = VSH_OT_BOOL,
.help = N_("delete snapshot and all children")
},
{.name = "children-only",
.type = VSH_OT_BOOL,
.help = N_("delete children but not snapshot")
},
{.name = "metadata",
.type = VSH_OT_BOOL,
.help = N_("delete only libvirt metadata, leaving snapshot contents behind")
},
{.name = NULL}
};
static bool
cmdSnapshotDelete(vshControl *ctl, const vshCmd *cmd)
{
virDomainPtr dom = NULL;
bool ret = false;
const char *name = NULL;
virDomainSnapshotPtr snapshot = NULL;
unsigned int flags = 0;
dom = virshCommandOptDomain(ctl, cmd, NULL);
if (dom == NULL)
goto cleanup;
if (virshLookupSnapshot(ctl, cmd, "snapshotname", true, dom,
&snapshot, &name) < 0)
goto cleanup;
if (vshCommandOptBool(cmd, "children"))
flags |= VIR_DOMAIN_SNAPSHOT_DELETE_CHILDREN;
if (vshCommandOptBool(cmd, "children-only"))
flags |= VIR_DOMAIN_SNAPSHOT_DELETE_CHILDREN_ONLY;
if (vshCommandOptBool(cmd, "metadata"))
flags |= VIR_DOMAIN_SNAPSHOT_DELETE_METADATA_ONLY;
/* XXX If we wanted, we could emulate DELETE_CHILDREN_ONLY even on
* older servers that reject the flag, by manually computing the
* list of descendants. But that's a lot of code to maintain. */
if (virDomainSnapshotDelete(snapshot, flags) == 0) {
if (flags & VIR_DOMAIN_SNAPSHOT_DELETE_CHILDREN_ONLY)
vshPrintExtra(ctl, _("Domain snapshot %s children deleted\n"), name);
else
vshPrintExtra(ctl, _("Domain snapshot %s deleted\n"), name);
} else {
vshError(ctl, _("Failed to delete snapshot %s"), name);
goto cleanup;
}
ret = true;
cleanup:
virshDomainSnapshotFree(snapshot);
virshDomainFree(dom);
return ret;
}
const vshCmdDef snapshotCmds[] = {
{.name = "snapshot-create",
.handler = cmdSnapshotCreate,
.opts = opts_snapshot_create,
.info = info_snapshot_create,
.flags = 0
},
{.name = "snapshot-create-as",
.handler = cmdSnapshotCreateAs,
.opts = opts_snapshot_create_as,
.info = info_snapshot_create_as,
.flags = 0
},
{.name = "snapshot-current",
.handler = cmdSnapshotCurrent,
.opts = opts_snapshot_current,
.info = info_snapshot_current,
.flags = 0
},
{.name = "snapshot-delete",
.handler = cmdSnapshotDelete,
.opts = opts_snapshot_delete,
.info = info_snapshot_delete,
.flags = 0
},
{.name = "snapshot-dumpxml",
.handler = cmdSnapshotDumpXML,
.opts = opts_snapshot_dumpxml,
.info = info_snapshot_dumpxml,
.flags = 0
},
{.name = "snapshot-edit",
.handler = cmdSnapshotEdit,
.opts = opts_snapshot_edit,
.info = info_snapshot_edit,
.flags = 0
},
{.name = "snapshot-info",
.handler = cmdSnapshotInfo,
.opts = opts_snapshot_info,
.info = info_snapshot_info,
.flags = 0
},
{.name = "snapshot-list",
.handler = cmdSnapshotList,
.opts = opts_snapshot_list,
.info = info_snapshot_list,
.flags = 0
},
{.name = "snapshot-parent",
.handler = cmdSnapshotParent,
.opts = opts_snapshot_parent,
.info = info_snapshot_parent,
.flags = 0
},
{.name = "snapshot-revert",
.handler = cmdDomainSnapshotRevert,
.opts = opts_snapshot_revert,
.info = info_snapshot_revert,
.flags = 0
},
{.name = NULL}
};