##// END OF EJS Templates
sparse: reliably avoid writing to store without a lock...
sparse: reliably avoid writing to store without a lock With the code as written before this patch we can still end up writing to store in `debugsparse`. Obviously we'll write to it if by accident a store requirement is modified, but more importantly we write to it if another concurrent transaction modifies the requirements file on disk. We can't rule this out since we're not holding the store lock, so it's better to explicitly pass a permission to write instead of inferring it based on file contents.

File last commit:

r50201:2e726c93 default
r52699:95cdc01f default
Show More
txnutil.py
32 lines | 943 B | text/x-python | PythonLexer
# txnutil.py - transaction related utilities
#
# Copyright FUJIWARA Katsunori <foozy@lares.dti.ne.jp> and others
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from . import encoding
def mayhavepending(root):
"""return whether 'root' may have pending changes, which are
visible to this process.
"""
return root == encoding.environ.get(b'HG_PENDING')
def trypending(root, vfs, filename, **kwargs):
"""Open file to be read according to HG_PENDING environment variable
This opens '.pending' of specified 'filename' only when HG_PENDING
is equal to 'root'.
This returns '(fp, is_pending_opened)' tuple.
"""
if mayhavepending(root):
try:
return (vfs(b'%s.pending' % filename, **kwargs), True)
except FileNotFoundError:
pass
return (vfs(filename, **kwargs), False)