parsers: make pack_dirstate take now in integer for consistency
On recent OS, 'stat.st_mtime' has a double precision floating point
value to represent nano seconds, but it is not wide enough for actual
file timestamp: nowadays, only 52 - 32 = 20 bit width is available for
decimal places in sec.
Therefore, casting it to 'int' may cause unexpected result. See also
changeset 13272104bb07 fixing issue4836 for detail.
For example, changed file A may be treated as "clean" unexpectedly in
steps below. "rounded now" is the value gotten by rounding via
'int(st.st_mtime)' or so.
---------------------+--------------------+------------------------
"now" | | timestamp of A (time_t)
float rounded time_t| action | FS dirstate
------ ------- ------+--------------------+-------- ---------------
N+.nnn N N | | --- ---
| update file A | N
| dirstate.normal(A) | N
N+.999 N+1 N | |
| dirstate.write() | N (*1)
| : |
| change file A | N
| : |
N+1.00 N+1 N+1 | |
| "hg status" (*2) | N N
------ ------- ------+--------------------+-------- ---------------
Timestamp N of A in dirstate isn't dropped at (*1), because "rounded
now" is N+1 at that time, even if 'st_mtime' in 'time_t' is still N.
Then, file A is unexpectedly treated as "clean" at (*2) in this case.
For consistent handling of 'stat.st_mtime', this patch makes
'pack_dirstate()' take 'now' argument not in floating point but in
integer.
This patch makes 'PyArg_ParseTuple()' in 'pack_dirstate()' use format
'i' (= checking type mismatch or overflow), even though it is ensured
that 'now' is in the range of 32bit signed integer by masking with
'_rangemask' (= 0x7fffffff) on caller side.
It should be cheaper enough than packing itself, and useful to
detect that legacy code invokes 'pack_dirstate()' with 'now' in
floating point value.
# extension to emulate invoking 'dirstate.write()' at the time
# specified by '[fakedirstatewritetime] fakenow', only when
# 'dirstate.write()' is invoked via functions below:
#
# - 'workingctx._checklookup()' (= 'repo.status()')
# - 'committablectx.markcommitted()'
from mercurial import context, extensions, parsers, util
def pack_dirstate(fakenow, orig, dmap, copymap, pl, now):
# execute what original parsers.pack_dirstate should do actually
# for consistency
actualnow = int(now)
for f, e in dmap.iteritems():
if e[0] == 'n' and e[3] == actualnow:
e = parsers.dirstatetuple(e[0], e[1], e[2], -1)
dmap[f] = e
return orig(dmap, copymap, pl, fakenow)
def fakewrite(ui, func):
# fake "now" of 'pack_dirstate' only if it is invoked while 'func'
fakenow = ui.config('fakedirstatewritetime', 'fakenow')
if not fakenow:
# Execute original one, if fakenow isn't configured. This is
# useful to prevent subrepos from executing replaced one,
# because replacing 'parsers.pack_dirstate' is also effective
# in subrepos.
return func()
# parsing 'fakenow' in YYYYmmddHHMM format makes comparison between
# 'fakenow' value and 'touch -t YYYYmmddHHMM' argument easy
fakenow = util.parsedate(fakenow, ['%Y%m%d%H%M'])[0]
orig_pack_dirstate = parsers.pack_dirstate
wrapper = lambda *args: pack_dirstate(fakenow, orig_pack_dirstate, *args)
parsers.pack_dirstate = wrapper
try:
return func()
finally:
parsers.pack_dirstate = orig_pack_dirstate
def _checklookup(orig, workingctx, files):
ui = workingctx.repo().ui
return fakewrite(ui, lambda : orig(workingctx, files))
def markcommitted(orig, committablectx, node):
ui = committablectx.repo().ui
return fakewrite(ui, lambda : orig(committablectx, node))
def extsetup(ui):
extensions.wrapfunction(context.workingctx, '_checklookup',
_checklookup)
extensions.wrapfunction(context.committablectx, 'markcommitted',
markcommitted)