[libvirt] [PATCH v2 4/5] qemu: Split out filling of JSONDiskNameLookup data

[John Ferlan]

Create a helper function which will do the primary work required to
find the specific device and get the disk name. Done in preparation for
some more code reuse.

Add new elements to _qemuMonitorJSONQueryBlockArgs in order to handle
the lookup of just one specific device from the query-block code.

Signed-off-by: John Ferlan <jferlan at redhat.com>
---
 src/qemu/qemu_monitor_json.c | 43 +++++++++++++++++++++++++++++++++++--------
 1 file changed, 35 insertions(+), 8 deletions(-)

diff --git a/src/qemu/qemu_monitor_json.c b/src/qemu/qemu_monitor_json.c
index f2589fc..2b03f86 100644
--- a/src/qemu/qemu_monitor_json.c
+++ b/src/qemu/qemu_monitor_json.c
@@ -4030,6 +4030,34 @@ qemuMonitorJSONDiskNameLookupOne(virJSONValuePtr image,
 }
 
 
+/* If the current device (thisdev) is the one we're looking for (searchDevice),
+ * then call LookupOne returning the desired name.
+ *
+ * Returns 0 on not found, 1 when thisdev and searchDevice match - it is up
+ * to the caller to determine whether @foundDevice is filled in
+ */
+static int
+qemuMonitorJSONQueryBlockFillDiskNameLookup(virJSONValuePtr dev,
+                                            const char *thisdev,
+                                            const char *searchDevice,
+                                            virStorageSourcePtr top,
+                                            virStorageSourcePtr target,
+                                            char **foundDevice)
+{
+    virJSONValuePtr inserted;
+    virJSONValuePtr image;
+
+    if (STREQ(thisdev, searchDevice)) {
+        if ((inserted = virJSONValueObjectGetObject(dev, "inserted")) &&
+            (image = virJSONValueObjectGetObject(inserted, "image"))) {
+            *foundDevice = qemuMonitorJSONDiskNameLookupOne(image, top, target);
+        }
+        return 1;
+    }
+    return 0;
+}
+
+
 char *
 qemuMonitorJSONDiskNameLookup(qemuMonitorPtr mon,
                               const char *device,
@@ -4052,9 +4080,8 @@ qemuMonitorJSONDiskNameLookup(qemuMonitorPtr mon,
 
     for (i = 0; i < virJSONValueArraySize(devices); i++) {
         virJSONValuePtr dev = virJSONValueArrayGet(devices, i);
-        virJSONValuePtr inserted;
-        virJSONValuePtr image;
         const char *thisdev;
+        int rc;
 
         if (!dev || dev->type != VIR_JSON_TYPE_OBJECT) {
             virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
@@ -4068,13 +4095,13 @@ qemuMonitorJSONDiskNameLookup(qemuMonitorPtr mon,
             goto cleanup;
         }
 
-        if (STREQ(thisdev, device)) {
-            if ((inserted = virJSONValueObjectGetObject(dev, "inserted")) &&
-                (image = virJSONValueObjectGetObject(inserted, "image"))) {
-                ret = qemuMonitorJSONDiskNameLookupOne(image, top, target);
-            }
+        if ((rc = qemuMonitorJSONQueryBlockFillDiskNameLookup(dev, thisdev,
+                                                              device, top,
+                                                              target,
+                                                              &ret)) < 0)
+            goto cleanup;
+        if (rc == 1)
             break;
-        }
     }
     /* Guarantee an error when returning NULL, but don't override a
      * more specific error if one was already generated.  */
-- 
2.7.4