revisionbranchcache: fall back to slow path if starting readonly (issue4531)
Transitioning to Mercurial versions with revision branch cache could be slow as
long as all operations were readonly (revset queries) and the cache would be
populated but not written back.
Instead, fall back to using the consistently slow path when readonly and the
cache doesn't exist yet. That avoids the overhead of populating the cache
without writing it back.
If not readonly, it will still populate all missing entries initially. That
avoids repeated writing of the cache file with small updates, and it also makes
sure a fully populated cache available for the readonly operations.
# fixpax - fix ownership in bdist_mpkg output
#
# Copyright 2015 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms of the
# MIT license (http://opensource.org/licenses/MIT)
"""Set file ownership to 0 in an Archive.pax.gz.
Suitable for fixing files bdist_mpkg output:
*.mpkg/Contents/Packages/*.pkg/Contents/Archive.pax.gz
"""
import sys, os, gzip
def fixpax(iname, oname):
i = gzip.GzipFile(iname)
o = gzip.GzipFile(oname, "w")
while True:
magic = i.read(6)
dev = i.read(6)
ino = i.read(6)
mode = i.read(6)
i.read(6) # uid
i.read(6) # gid
nlink = i.read(6)
rdev = i.read(6)
mtime = i.read(11)
namesize = i.read(6)
filesize = i.read(11)
name = i.read(int(namesize, 8))
data = i.read(int(filesize, 8))
o.write(magic)
o.write(dev)
o.write(ino)
o.write(mode)
o.write("000000")
o.write("000000")
o.write(nlink)
o.write(rdev)
o.write(mtime)
o.write(namesize)
o.write(filesize)
o.write(name)
o.write(data)
if name.startswith("TRAILER!!!"):
o.write(i.read())
break
o.close()
i.close()
if __name__ == '__main__':
for iname in sys.argv[1:]:
print 'fixing file ownership in %s' % iname
oname = sys.argv[1] + '.tmp'
fixpax(iname, oname)
os.rename(oname, iname)