The cluster size of an image is the QcowHeader class member and may be obtained by dependent extension structures such as Qcow2BitmapExt for further bitmap table details print.
Signed-off-by: Andrey Shinkevich <andrey.shinkev...@virtuozzo.com> --- tests/qemu-iotests/qcow2_format.py | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/tests/qemu-iotests/qcow2_format.py b/tests/qemu-iotests/qcow2_format.py index 7c0dc9a..cfd9646 100644 --- a/tests/qemu-iotests/qcow2_format.py +++ b/tests/qemu-iotests/qcow2_format.py @@ -130,14 +130,16 @@ class Qcow2BitmapExt(Qcow2Struct): ('u64', '{:#x}', 'bitmap_directory_offset') ) - def __init__(self, fd): + def __init__(self, fd, cluster_size): super().__init__(fd=fd) + self.cluster_size = cluster_size self.read_bitmap_directory(fd) def read_bitmap_directory(self, fd): fd.seek(self.bitmap_directory_offset) self.bitmap_directory = \ - [Qcow2BitmapDirEntry(fd) for _ in range(self.nb_bitmaps)] + [Qcow2BitmapDirEntry(fd, cluster_size=self.cluster_size) + for _ in range(self.nb_bitmaps)] def dump(self): super().dump() @@ -158,8 +160,9 @@ class Qcow2BitmapDirEntry(Qcow2Struct): ('u32', '{}', 'extra_data_size') ) - def __init__(self, fd): + def __init__(self, fd, cluster_size): super().__init__(fd=fd) + self.cluster_size = cluster_size # Seek relative to the current position in the file fd.seek(self.extra_data_size, 1) bitmap_name = fd.read(self.name_size) @@ -199,11 +202,13 @@ class QcowHeaderExtension(Qcow2Struct): # then padding to next multiply of 8 ) - def __init__(self, magic=None, length=None, data=None, fd=None): + def __init__(self, magic=None, length=None, data=None, fd=None, + cluster_size=None): """ Support both loading from fd and creation from user data. For fd-based creation current position in a file will be used to read the data. + The cluster_size value may be obtained by dependent structures. This should be somehow refactored and functionality should be moved to superclass (to allow creation of any qcow2 struct), but then, fields @@ -242,7 +247,7 @@ class QcowHeaderExtension(Qcow2Struct): # Step back to reread data padded = (self.length + 7) & ~7 fd.seek(-padded, 1) - self.obj = Qcow2BitmapExt(fd=fd) + self.obj = Qcow2BitmapExt(fd=fd, cluster_size=cluster_size) fd.seek(position) else: self.obj = None @@ -318,7 +323,7 @@ class QcowHeader(Qcow2Struct): end = self.cluster_size while fd.tell() < end: - ext = QcowHeaderExtension(fd=fd) + ext = QcowHeaderExtension(fd=fd, cluster_size=self.cluster_size) if ext.magic == 0: break else: -- 1.8.3.1