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Differential D10898

censor: extract the part about writing the censored revision in a function
ClosedPublic

Authored by marmoute on Jun 22 2021, 7:27 PM.

Details

Reviewers
Alphare
Group Reviewers
hg-reviewers
Commits
rHG3ab267f0cbe4: censor: extract the part about writing the censored revision in a function
Summary

The v2_censor function is huge, now that its content has settled a bit it is a
good time to split individual part inside dedicated function. We start with a
small function that process the censored revision.

Diff Detail

Repository
rHG Mercurial
Lint
Automatic diff as part of commit; lint not applicable.
Unit
Automatic diff as part of commit; unit tests not applicable.

Revision Contents
Changeset List

PathPackages
Mmercurial/revlogutils/rewrite.py (87 lines)

Diff 28709

mercurial/revlogutils/rewrite.py

) = open_files ) = open_files
new_index_file.seek(0, os.SEEK_END) new_index_file.seek(0, os.SEEK_END)
assert new_index_file.tell() == index_cutoff assert new_index_file.tell() == index_cutoff
new_data_file.seek(0, os.SEEK_END) new_data_file.seek(0, os.SEEK_END)
assert new_data_file.tell() == data_cutoff assert new_data_file.tell() == data_cutoff
new_sidedata_file.seek(0, os.SEEK_END) new_sidedata_file.seek(0, os.SEEK_END)
assert new_sidedata_file.tell() == sidedata_cutoff assert new_sidedata_file.tell() == sidedata_cutoff
### writing the censored revision # writing the censored revision
entry = old_index[censor_rev] _rewrite_censor(
rl,
# XXX consider trying the default compression too old_index,
new_data_size = len(tombstone) open_files,
new_data_offset = new_data_file.tell() censor_rev,
new_data_file.write(tombstone) tombstone,
# we are not adding any sidedata as they might leak info about the censored version
new_entry = revlogutils.entry(
flags=constants.REVIDX_ISCENSORED,
data_offset=new_data_offset,
data_compressed_length=new_data_size,
data_uncompressed_length=new_data_size,
data_delta_base=censor_rev,
link_rev=entry[ENTRY_LINK_REV],
parent_rev_1=entry[ENTRY_PARENT_1],
parent_rev_2=entry[ENTRY_PARENT_2],
node_id=entry[ENTRY_NODE_ID],
sidedata_offset=0,
sidedata_compressed_length=0,
data_compression_mode=COMP_MODE_PLAIN,
sidedata_compression_mode=COMP_MODE_PLAIN,
) )
rl.index.append(new_entry)
entry_bin = rl.index.entry_binary(censor_rev)
new_index_file.write(entry_bin)
docket.index_end = new_index_file.tell()
docket.data_end = new_data_file.tell()
#### Writing all subsequent revisions #### Writing all subsequent revisions
for rev in range(censor_rev + 1, len(old_index)): for rev in range(censor_rev + 1, len(old_index)):
entry = old_index[rev] entry = old_index[rev]
flags = entry[ENTRY_DATA_OFFSET] & 0xFFFF flags = entry[ENTRY_DATA_OFFSET] & 0xFFFF
old_data_offset = entry[ENTRY_DATA_OFFSET] >> 16 old_data_offset = entry[ENTRY_DATA_OFFSET] >> 16
if rev not in rewritten_entries: if rev not in rewritten_entries:
entry_bin = rl.index.entry_binary(rev) entry_bin = rl.index.entry_binary(rev)
new_index_file.write(entry_bin) new_index_file.write(entry_bin)
docket.index_end = new_index_file.tell() docket.index_end = new_index_file.tell()
docket.data_end = new_data_file.tell() docket.data_end = new_data_file.tell()
docket.sidedata_end = new_sidedata_file.tell() docket.sidedata_end = new_sidedata_file.tell()
docket.write(transaction=None, stripping=True) docket.write(transaction=None, stripping=True)
def _rewrite_censor(
revlog,
old_index,
all_files,
rev,
tombstone,
):
"""rewrite and append a censored revision"""
(
old_data_file,
old_sidedata_file,
new_index_file,
new_data_file,
new_sidedata_file,
) = all_files
entry = old_index[rev]
# XXX consider trying the default compression too
new_data_size = len(tombstone)
new_data_offset = new_data_file.tell()
new_data_file.write(tombstone)
# we are not adding any sidedata as they might leak info about the censored version
link_rev = entry[ENTRY_LINK_REV]
p1 = entry[ENTRY_PARENT_1]
p2 = entry[ENTRY_PARENT_2]
new_entry = revlogutils.entry(
flags=constants.REVIDX_ISCENSORED,
data_offset=new_data_offset,
data_compressed_length=new_data_size,
data_uncompressed_length=new_data_size,
data_delta_base=rev,
link_rev=link_rev,
parent_rev_1=p1,
parent_rev_2=p2,
node_id=entry[ENTRY_NODE_ID],
sidedata_offset=0,
sidedata_compressed_length=0,
data_compression_mode=COMP_MODE_PLAIN,
sidedata_compression_mode=COMP_MODE_PLAIN,
)
revlog.index.append(new_entry)
entry_bin = revlog.index.entry_binary(rev)
new_index_file.write(entry_bin)
revlog._docket.index_end = new_index_file.tell()
revlog._docket.data_end = new_data_file.tell()