[libvirt] [PATCHv2 1/2] virsh: Refactor error clearing on graceful fallback paths

Virsh uses an error handler to save errors from libvirt. On some code paths it's needed to clear libvirt errors and continue on fallback code paths without reporting failure. This patch adds function vshResetLibvirtError() that clears error returned by libvirt and updates all places where the old two-line method was used. --- tools/virsh-domain-monitor.c | 12 ++++-------- tools/virsh-domain.c | 36 ++++++++++++------------------------ tools/virsh-network.c | 3 +-- tools/virsh-pool.c | 3 +-- tools/virsh-snapshot.c | 15 +++++---------- tools/virsh.c | 13 +++++++++++-- 6 files changed, 34 insertions(+), 48 deletions(-) diff --git a/tools/virsh-domain-monitor.c b/tools/virsh-domain-monitor.c index 68d5983..65a9808 100644 --- a/tools/virsh-domain-monitor.c +++ b/tools/virsh-domain-monitor.c @@ -849,8 +849,7 @@ cmdDomblkstat(vshControl *ctl, const vshCmd *cmd) if (last_error->code != VIR_ERR_NO_SUPPORT) goto cleanup; - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); if (virDomainBlockStats(dom, device, &stats, sizeof(stats)) == -1) { @@ -1166,8 +1165,7 @@ cmdDominfo(vshControl *ctl, const vshCmd *cmd) virDomainFree(dom); return false; } else { - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); } } else { /* Only print something if a security model is active */ @@ -1340,8 +1338,7 @@ vshDomainListCollect(vshControl *ctl, unsigned int flags) /* check if the command is actually supported */ if (last_error && last_error->code == VIR_ERR_NO_SUPPORT) { - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); goto fallback; } @@ -1350,8 +1347,7 @@ vshDomainListCollect(vshControl *ctl, unsigned int flags) unsigned int newflags = flags & (VIR_CONNECT_LIST_DOMAINS_ACTIVE | VIR_CONNECT_LIST_DOMAINS_INACTIVE); - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); if ((ret = virConnectListAllDomains(ctl->conn, &list->domains, newflags)) >= 0) { list->ndomains = ret; diff --git a/tools/virsh-domain.c b/tools/virsh-domain.c index cb77ca4..33b1727 100644 --- a/tools/virsh-domain.c +++ b/tools/virsh-domain.c @@ -2332,8 +2332,7 @@ cmdUndefine(vshControl *ctl, const vshCmd *cmd) if (has_managed_save < 0) { if (last_error->code != VIR_ERR_NO_SUPPORT) goto error; - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); has_managed_save = 0; } @@ -2341,8 +2340,7 @@ cmdUndefine(vshControl *ctl, const vshCmd *cmd) if (has_snapshots < 0) { if (last_error->code != VIR_ERR_NO_SUPPORT) goto error; - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); has_snapshots = 0; } if (has_snapshots) { @@ -2351,8 +2349,7 @@ cmdUndefine(vshControl *ctl, const vshCmd *cmd) if (has_snapshots_metadata < 0) { /* The server did not know the new flag, assume that all snapshots have metadata. */ - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); has_snapshots_metadata = has_snapshots; } else { /* The server knew the new flag, all aspects of @@ -2461,8 +2458,7 @@ cmdUndefine(vshControl *ctl, const vshCmd *cmd) vshPrint(ctl, _("Storage volume '%s'(%s) is not managed by libvirt. " "Remove it manually.\n"), target, source); - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); continue; } vlist[nvols].source = source; @@ -2497,8 +2493,7 @@ cmdUndefine(vshControl *ctl, const vshCmd *cmd) if (rc == 0 || (last_error->code != VIR_ERR_NO_SUPPORT && last_error->code != VIR_ERR_INVALID_ARG)) goto out; - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); } /* The new API is unsupported or unsafe; fall back to doing things @@ -2657,13 +2652,11 @@ cmdStart(vshControl *ctl, const vshCmd *cmd) virshReportError(ctl); goto cleanup; } - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); rc = virDomainHasManagedSaveImage(dom, 0); if (rc < 0) { /* No managed save image to remove */ - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); } else if (rc > 0) { if (virDomainManagedSaveRemove(dom, 0) < 0) { virshReportError(ctl); @@ -4173,8 +4166,7 @@ cmdVcpucount(vshControl *ctl, const vshCmd *cmd) if (!tmp || virStrToLong_i(tmp + 1, &tmp, 10, &count) < 0) count = -1; } - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); VIR_FREE(xml); } @@ -4187,8 +4179,7 @@ cmdVcpucount(vshControl *ctl, const vshCmd *cmd) } else { vshPrint(ctl, "%d\n", count); } - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); } if (all || (maximum && live)) { @@ -4208,8 +4199,7 @@ cmdVcpucount(vshControl *ctl, const vshCmd *cmd) } else { vshPrint(ctl, "%d\n", count); } - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); } if (all || (active && config)) { @@ -4245,8 +4235,7 @@ cmdVcpucount(vshControl *ctl, const vshCmd *cmd) } else { vshPrint(ctl, "%d\n", count); } - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); } if (all || (active && live)) { @@ -4267,8 +4256,7 @@ cmdVcpucount(vshControl *ctl, const vshCmd *cmd) } else { vshPrint(ctl, "%d\n", count); } - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); } virDomainFree(dom); diff --git a/tools/virsh-network.c b/tools/virsh-network.c index 69a766d..49ec34f 100644 --- a/tools/virsh-network.c +++ b/tools/virsh-network.c @@ -639,8 +639,7 @@ static char *vshNetworkGetXMLDesc(virNetworkPtr network) /* The server side libvirt doesn't support * VIR_NETWORK_XML_INACTIVE, so retry without it. */ - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); flags &= ~VIR_NETWORK_XML_INACTIVE; doc = virNetworkGetXMLDesc(network, flags); } diff --git a/tools/virsh-pool.c b/tools/virsh-pool.c index ccd9b79..af80427 100644 --- a/tools/virsh-pool.c +++ b/tools/virsh-pool.c @@ -1379,8 +1379,7 @@ cmdPoolEdit(vshControl *ctl, const vshCmd *cmd) if (!(tmp_desc = virStoragePoolGetXMLDesc(pool, flags))) { if (last_error->code == VIR_ERR_INVALID_ARG) { flags &= ~VIR_STORAGE_XML_INACTIVE; - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); } else { goto cleanup; } diff --git a/tools/virsh-snapshot.c b/tools/virsh-snapshot.c index 9182c9a..92f0d6c 100644 --- a/tools/virsh-snapshot.c +++ b/tools/virsh-snapshot.c @@ -43,8 +43,7 @@ vshSnapshotCreate(vshControl *ctl, virDomainPtr dom, const char *buffer, (flags & VIR_DOMAIN_SNAPSHOT_CREATE_HALT)) { int persistent; - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); persistent = virDomainIsPersistent(dom); if (persistent < 0) { virshReportError(ctl); @@ -644,8 +643,7 @@ cleanup: virshReportError(ctl); vshError(ctl, "%s", _("unable to determine if snapshot has parent")); } else { - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); } if (parent) virDomainSnapshotFree(parent); @@ -932,8 +930,7 @@ vshSnapshotListCollect(vshControl *ctl, virDomainPtr dom, last_error->code == VIR_ERR_NO_SUPPORT)) { /* We can emulate --from. */ /* XXX can we also emulate --leaves? */ - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); ctl->useSnapshotOld = true; flags &= ~VIR_DOMAIN_SNAPSHOT_LIST_DESCENDANTS; goto global; @@ -950,8 +947,7 @@ vshSnapshotListCollect(vshControl *ctl, virDomainPtr dom, /* XXX can we also emulate --leaves? */ if (!from && count < 0 && last_error->code == VIR_ERR_INVALID_ARG && (flags & VIR_DOMAIN_SNAPSHOT_LIST_ROOTS)) { - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); roots = true; flags &= ~VIR_DOMAIN_SNAPSHOT_LIST_ROOTS; count = virDomainSnapshotNum(dom, flags); @@ -1514,8 +1510,7 @@ cmdDomainSnapshotRevert(vshControl *ctl, const vshCmd *cmd) if (result < 0 && force && last_error->code == VIR_ERR_SNAPSHOT_REVERT_RISKY) { flags |= VIR_DOMAIN_SNAPSHOT_REVERT_FORCE; - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); result = virDomainRevertToSnapshot(snapshot, flags); } if (result < 0) diff --git a/tools/virsh.c b/tools/virsh.c index 5658796..15a0dc7 100644 --- a/tools/virsh.c +++ b/tools/virsh.c @@ -492,6 +492,16 @@ virshErrorHandler(void *unused ATTRIBUTE_UNUSED, virErrorPtr error) } /* + * Reset libvirt error on graceful fallback paths + */ +static void +vshResetLibvirtError(void) +{ + virFreeError(last_error); + last_error = NULL; +} + +/* * Report an error when a command finishes. This is better than before * (when correct operation would report errors), but it has some * problems: we lose the smarter formatting of virDefaultErrorFunc(), @@ -521,8 +531,7 @@ virshReportError(vshControl *ctl) vshError(ctl, "%s", last_error->message); out: - virFreeError(last_error); - last_error = NULL; + vshResetLibvirtError(); } static volatile sig_atomic_t intCaught = 0; -- 1.7.8.6