def resolve_object(self, offset, type, obj, get_ref, get_offset=None):
"""Resolve an object, possibly resolving deltas when necessary.
:return: Tuple with object type and contents.
"""
if type not in (6, 7): # Not a delta
return type, obj
if get_offset is None:
get_offset = self.get_object_at
if type == 6: # offset delta
(delta_offset, delta) = obj
assert isinstance(delta_offset, int)
assert isinstance(delta, str)
base_offset = offset-delta_offset
type, base_obj = get_offset(base_offset)
assert isinstance(type, int)
elif type == 7: # ref delta
(basename, delta) = obj
assert isinstance(basename, str) and len(basename) == 20
assert isinstance(delta, str)
type, base_obj = get_ref(basename)
assert isinstance(type, int)
# Can't be a ofs delta, as we wouldn't know the base offset
assert type != 6
base_offset = None
type, base_text = self.resolve_object(base_offset, type, base_obj, get_ref)
if base_offset is not None:
self._offset_cache[base_offset] = type, base_text
ret = (type, apply_delta(base_text, delta))
return ret
def resolve_object(self, offset, type, obj, get_ref=None):
"""Resolve an object, possibly resolving deltas when necessary.
:return: Tuple with object type and contents.
"""
if type not in DELTA_TYPES:
return type, obj
if get_ref is None:
get_ref = self.get_ref
if type == OFS_DELTA:
(delta_offset, delta) = obj
# TODO: clean up asserts and replace with nicer error messages
assert isinstance(offset, int)
assert isinstance(delta_offset, int)
base_offset = offset-delta_offset
type, base_obj = self.get_object_at(base_offset)
assert isinstance(type, int)
elif type == REF_DELTA:
(basename, delta) = obj
assert isinstance(basename, str) and len(basename) == 20
base_offset, type, base_obj = get_ref(basename)
assert isinstance(type, int)
type, base_chunks = self.resolve_object(base_offset, type, base_obj)
chunks = apply_delta(base_chunks, delta)
# TODO(dborowitz): This can result in poor performance if large base
# objects are separated from deltas in the pack. We should reorganize
# so that we apply deltas to all objects in a chain one after the other
# to optimize cache performance.
if offset is not None:
self._offset_cache[offset] = type, chunks
return type, chunks
def resolve_object(self, offset, type, obj, get_ref=None):
"""Resolve an object, possibly resolving deltas when necessary.
:return: Tuple with object type and contents.
"""
if type not in DELTA_TYPES:
return type, obj
if get_ref is None:
get_ref = self.get_ref
if type == OFS_DELTA:
(delta_offset, delta) = obj
# TODO: clean up asserts and replace with nicer error messages
assert isinstance(offset, int)
assert isinstance(delta_offset, int)
base_offset = offset-delta_offset
type, base_obj = self.get_object_at(base_offset)
assert isinstance(type, int)
elif type == REF_DELTA:
(basename, delta) = obj
assert isinstance(basename, str) and len(basename) == 20
base_offset, type, base_obj = get_ref(basename)
assert isinstance(type, int)
type, base_chunks = self.resolve_object(base_offset, type, base_obj)
chunks = apply_delta(base_chunks, delta)
# TODO(dborowitz): This can result in poor performance if large base
# objects are separated from deltas in the pack. We should reorganize
# so that we apply deltas to all objects in a chain one after the other
# to optimize cache performance.
if offset is not None:
self._offset_cache[offset] = type, chunks
return type, chunks
def resolve_object(self, offset, type, obj, get_ref, get_offset=None):
"""Resolve an object, possibly resolving deltas when necessary.
:return: Tuple with object type and contents.
"""
if type not in (6, 7): # Not a delta
return type, obj
if get_offset is None:
get_offset = self.get_object_at
if type == 6: # offset delta
(delta_offset, delta) = obj
assert isinstance(delta_offset, int)
assert isinstance(delta, str)
base_offset = offset - delta_offset
type, base_obj = get_offset(base_offset)
assert isinstance(type, int)
elif type == 7: # ref delta
(basename, delta) = obj
assert isinstance(basename, str) and len(basename) == 20
assert isinstance(delta, str)
type, base_obj = get_ref(basename)
assert isinstance(type, int)
# Can't be a ofs delta, as we wouldn't know the base offset
assert type != 6
base_offset = None
type, base_text = self.resolve_object(base_offset, type, base_obj,
get_ref)
if base_offset is not None:
self._offset_cache[base_offset] = type, base_text
ret = (type, apply_delta(base_text, delta))
return ret
