[PULL 04/14] qcow2_format.py: dump bitmap flags in human readable way.

[Eric Blake]

From: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>

Introduce the class BitmapFlags that parses a bitmap flags mask.

Suggested-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <1596742557-320265-5-git-send-email-andrey.shinkevich@virtuozzo.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
---
 tests/qemu-iotests/qcow2_format.py | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/tests/qemu-iotests/qcow2_format.py 
b/tests/qemu-iotests/qcow2_format.py
index d4a997453758..b4473442c9d4 100644
--- a/tests/qemu-iotests/qcow2_format.py
+++ b/tests/qemu-iotests/qcow2_format.py
@@ -40,6 +40,22 @@ class Flags64(Qcow2Field):
         return str(bits)


+class BitmapFlags(Qcow2Field):
+
+    flags = {
+        0x1: 'in-use',
+        0x2: 'auto'
+    }
+
+    def __str__(self):
+        bits = []
+        for bit in range(64):
+            flag = self.value & (1 << bit)
+            if flag:
+                bits.append(self.flags.get(flag, f'bit-{bit}'))
+        return f'{self.value:#x} ({bits})'
+
+
 class Enum(Qcow2Field):

     def __str__(self):
-- 
2.28.0