qemu: domainjob: Allow operations if cb is not set in job structure

We should allow resetting / freeing / restoring / parsing /
formatting qemuDomainJobObj even if 'cb' attribute is not set.
This is theoretical for now, but the attribute must not be always
set in the future. It is sufficient to check if 'cb' exists
before dereferencing it.

This commit partially reverts af16e754cd4efc3ca1.

Signed-off-by: Kristina Hanicova <khanicov@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>

diff --git a/src/qemu/qemu_domainjob.c b/src/qemu/qemu_domainjob.c
index 3e73eba4ed48c7a55f58376d47c430abc93faff0..7b81cd8a2b006def5835d22a91493550c7173616 100644 (file)
--- a/src/qemu/qemu_domainjob.c
+++ b/src/qemu/qemu_domainjob.c
@@ -239,8 +239,10 @@ qemuDomainObjResetAsyncJob(qemuDomainJobObj *job)
     job->abortJob = false;
     VIR_FREE(job->error);
     g_clear_pointer(&job->current, virDomainJobDataFree);
-    job->cb->resetJobPrivate(job->privateData);
     job->apiFlags = 0;
+
+    if (job->cb)
+        job->cb->resetJobPrivate(job->privateData);
 }
 
 int
@@ -258,7 +260,8 @@ qemuDomainObjRestoreJob(virDomainObj *obj,
     job->privateData = g_steal_pointer(&priv->job.privateData);
     job->apiFlags = priv->job.apiFlags;
 
-    if (!(priv->job.privateData = priv->job.cb->allocJobPrivate()))
+    if (priv->job.cb &&
+        !(priv->job.privateData = priv->job.cb->allocJobPrivate()))
         return -1;
     job->cb = priv->job.cb;
 
@@ -270,16 +273,15 @@ qemuDomainObjRestoreJob(virDomainObj *obj,
 void
 qemuDomainObjClearJob(qemuDomainJobObj *job)
 {
-    if (!job->cb)
-        return;
-
     qemuDomainObjResetJob(job);
     qemuDomainObjResetAsyncJob(job);
-    g_clear_pointer(&job->privateData, job->cb->freeJobPrivate);
     g_clear_pointer(&job->current, virDomainJobDataFree);
     g_clear_pointer(&job->completed, virDomainJobDataFree);
     virCondDestroy(&job->cond);
     virCondDestroy(&job->asyncCond);
+
+    if (job->cb)
+        g_clear_pointer(&job->privateData, job->cb->freeJobPrivate);
 }
 
 bool
@@ -1228,7 +1230,8 @@ qemuDomainObjPrivateXMLFormatJob(virBuffer *buf,
     if (priv->job.asyncJob != QEMU_ASYNC_JOB_NONE)
         virBufferAsprintf(&attrBuf, " flags='0x%lx'", priv->job.apiFlags);
 
-    if (priv->job.cb->formatJob(&childBuf, &priv->job, vm) < 0)
+    if (priv->job.cb &&
+        priv->job.cb->formatJob(&childBuf, &priv->job, vm) < 0)
         return -1;
 
     virXMLFormatElement(buf, "job", &attrBuf, &childBuf);
@@ -1288,7 +1291,8 @@ qemuDomainObjPrivateXMLParseJob(virDomainObj *vm,
         return -1;
     }
 
-    if (priv->job.cb->parseJob(ctxt, job, vm) < 0)
+    if (priv->job.cb &&
+        priv->job.cb->parseJob(ctxt, job, vm) < 0)
         return -1;
 
     return 0;