Changeset 14225 in vbox for trunk/src/VBox/Main/HardDisk2Impl.cpp

Timestamp:

Nov 14, 2008 5:55:28 PM (16 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

39341

Message:

Main: Use the parent's hard disk format when implicitly creating differencing hard disks (or the default hard disk format if the parent format doesn't support differencing).

File:

• trunk/src/VBox/Main/HardDisk2Impl.cpp (modified) (1 diff)

trunk/src/VBox/Main/HardDisk2Impl.cpp

@@ -1653 +1653 @@
     /* delegate the rest to the profi */
     cancelMergeTo (aChain);
+}
+
+/**
+ * Returns a preferred format for differencing hard disks.
+ */
+Bstr HardDisk2::preferredDiffFormat()
+{
+    Bstr format;
+
+    AutoCaller autoCaller (this);
+    AssertComRCReturn (autoCaller.rc(), format);
+
+    /* mm.format is const, no need to lock */
+    format = mm.format;
+
+    /* check that our own format supports diffs */
+
+    /* lock system properties now to make the format check atomic with
+     * defaultHardDiskFormat() */
+    AutoReadLock propsLock (mVirtualBox->systemProperties());
+
+    ComObjPtr <HardDiskFormat> formatObj =
+        mVirtualBox->systemProperties()->hardDiskFormat (format);
+    AssertReturn (!formatObj.isNull(), format);
+
+    if (!(formatObj->capabilities() & HardDiskFormatCapabilities_Differencing))
+        format = mVirtualBox->systemProperties()->defaultHardDiskFormat();
+
+    return format;
 }