apenwarr-redo/builder.py
Avery Pennarun 5596b9fae3 Better comment in t/flush-cache, and a avoid a (rare) unit test error.
flush-cache reduces the failed_runid by 1 each time, and it runs
multiple times per 'redo test'.  if failed_runid goes to zero, it would
be treated as success ("no failure") rather than a real failure at
runid 0.
2018-11-21 21:00:36 -05:00

513 lines
19 KiB
Python

import sys, os, errno, random, stat, signal, time
import vars, jwack, state, paths
from helpers import unlink, close_on_exec, join
import logs
from logs import debug, debug2, err, warn, meta, check_tty
def _nice(t):
return state.relpath(t, vars.STARTDIR)
def _try_stat(filename):
try:
return os.lstat(filename)
except OSError, e:
if e.errno == errno.ENOENT:
return None
else:
raise
log_reader_pid = None
def start_stdin_log_reader(status, details, pretty, color,
debug_locks, debug_pids):
if not vars.LOG: return
global log_reader_pid
r, w = os.pipe() # main pipe to redo-log
ar, aw = os.pipe() # ack pipe from redo-log --ack-fd
sys.stdout.flush()
sys.stderr.flush()
pid = os.fork()
if pid:
# parent
log_reader_pid = pid
os.close(r)
os.close(aw)
b = os.read(ar, 8)
if not b:
# subprocess died without sending us anything: that's bad.
err('failed to start redo-log subprocess; cannot continue.\n')
os._exit(99)
assert b == 'REDO-OK\n'
# now we know the subproc is running and will report our errors
# to stderr, so it's okay to lose our own stderr.
os.close(ar)
os.dup2(w, 1)
os.dup2(w, 2)
os.close(w)
check_tty(sys.stderr, vars.COLOR)
else:
# child
try:
os.close(ar)
os.close(w)
os.dup2(r, 0)
os.close(r)
# redo-log sends to stdout (because if you ask for logs, that's
# the output you wanted!). But redo itself sends logs to stderr
# (because they're incidental to the thing you asked for).
# To make these semantics work, we point redo-log's stdout at
# our stderr when we launch it.
os.dup2(2, 1)
argv = [
'redo-log',
'--recursive', '--follow',
'--ack-fd', str(aw),
('--status' if status and os.isatty(2) else '--no-status'),
('--details' if details else '--no-details'),
('--pretty' if pretty else '--no-pretty'),
('--debug-locks' if debug_locks else '--no-debug-locks'),
('--debug-pids' if debug_pids else '--no-debug-pids'),
]
if color != 1:
argv.append('--color' if color >= 2 else '--no-color')
argv.append('-')
os.execvp(argv[0], argv)
except Exception, e:
sys.stderr.write('redo-log: exec: %s\n' % e)
finally:
os._exit(99)
def await_log_reader():
if not vars.LOG: return
global log_reader_pid
if log_reader_pid > 0:
# never actually close fd#1 or fd#2; insanity awaits.
# replace it with something else instead.
# Since our stdout/stderr are attached to redo-log's stdin,
# this will notify redo-log that it's time to die (after it finishes
# reading the logs)
out = open('/dev/tty', 'w')
os.dup2(out.fileno(), 1)
os.dup2(out.fileno(), 2)
os.waitpid(log_reader_pid, 0)
class ImmediateReturn(Exception):
def __init__(self, rv):
Exception.__init__(self, "immediate return with exit code %d" % rv)
self.rv = rv
class BuildJob:
def __init__(self, t, sf, lock, shouldbuildfunc, donefunc):
self.t = t # original target name, not relative to vars.BASE
self.sf = sf
tmpbase = t
while not os.path.isdir(os.path.dirname(tmpbase) or '.'):
ofs = tmpbase.rfind('/')
assert(ofs >= 0)
tmpbase = tmpbase[:ofs] + '__' + tmpbase[ofs+1:]
self.tmpname1 = '%s.redo1.tmp' % tmpbase
self.tmpname2 = '%s.redo2.tmp' % tmpbase
self.lock = lock
self.shouldbuildfunc = shouldbuildfunc
self.donefunc = donefunc
self.before_t = _try_stat(self.t)
def start(self):
assert(self.lock.owned)
try:
try:
is_target, dirty = self.shouldbuildfunc(self.t)
except state.CyclicDependencyError:
err('cyclic dependency while checking %s\n' % _nice(self.t))
raise ImmediateReturn(208)
if not dirty:
# target doesn't need to be built; skip the whole task
if is_target:
meta('unchanged', state.target_relpath(self.t))
return self._after2(0)
except ImmediateReturn, e:
return self._after2(e.rv)
if vars.NO_OOB or dirty == True:
self._start_do()
else:
self._start_unlocked(dirty)
def _start_do(self):
assert(self.lock.owned)
t = self.t
sf = self.sf
newstamp = sf.read_stamp()
if (sf.is_generated and
newstamp != state.STAMP_MISSING and
(sf.is_override or state.detect_override(sf.stamp, newstamp))):
state.warn_override(_nice(t))
if not sf.is_override:
warn('%s - old: %r\n' % (_nice(t), sf.stamp))
warn('%s - new: %r\n' % (_nice(t), newstamp))
sf.set_override()
sf.set_checked()
sf.save()
return self._after2(0)
if (os.path.exists(t) and not os.path.isdir(t + '/.')
and not sf.is_generated):
# an existing source file that was not generated by us.
# This step is mentioned by djb in his notes.
# For example, a rule called default.c.do could be used to try
# to produce hello.c, but we don't want that to happen if
# hello.c was created by the end user.
debug2("-- static (%r)\n" % t)
sf.set_static()
sf.save()
return self._after2(0)
sf.zap_deps1()
(dodir, dofile, basedir, basename, ext) = paths.find_do_file(sf)
if not dofile:
if os.path.exists(t):
sf.set_static()
sf.save()
return self._after2(0)
else:
err('no rule to redo %r\n' % t)
return self._after2(1)
unlink(self.tmpname1)
unlink(self.tmpname2)
ffd = os.open(self.tmpname1, os.O_CREAT|os.O_RDWR|os.O_EXCL, 0666)
close_on_exec(ffd, True)
self.f = os.fdopen(ffd, 'w+')
# this will run in the dofile's directory, so use only basenames here
arg1 = basename + ext # target name (including extension)
arg2 = basename # target name (without extension)
argv = ['sh', '-e',
dofile,
arg1,
arg2,
# temp output file name
state.relpath(os.path.abspath(self.tmpname2), dodir),
]
if vars.VERBOSE: argv[1] += 'v'
if vars.XTRACE: argv[1] += 'x'
firstline = open(os.path.join(dodir, dofile)).readline().strip()
if firstline.startswith('#!/'):
argv[0:2] = firstline[2:].split(' ')
# make sure to create the logfile *before* writing the meta() about it.
# that way redo-log won't trace into an obsolete logfile.
if vars.LOG: open(state.logname(self.sf.id), 'w')
self.dodir = dodir
self.basename = basename
self.ext = ext
self.argv = argv
sf.is_generated = True
sf.save()
dof = state.File(name=os.path.join(dodir, dofile))
dof.set_static()
dof.save()
state.commit()
meta('do', state.target_relpath(t))
jwack.start_job(t, self._do_subproc, self._after)
def _start_unlocked(self, dirty):
# out-of-band redo of some sub-objects. This happens when we're not
# quite sure if t needs to be built or not (because some children
# look dirty, but might turn out to be clean thanks to checksums).
# We have to call redo-unlocked to figure it all out.
#
# Note: redo-unlocked will handle all the updating of sf, so we
# don't have to do it here, nor call _after1. However, we have to
# hold onto the lock because otherwise we would introduce a race
# condition; that's why it's called redo-unlocked, because it doesn't
# grab a lock.
here = os.getcwd()
def _fix(p):
return state.relpath(os.path.join(vars.BASE, p), here)
argv = (['redo-unlocked', _fix(self.sf.name)] +
list(set(_fix(d.name) for d in dirty)))
meta('check', state.target_relpath(self.t))
state.commit()
def run():
os.environ['REDO_DEPTH'] = vars.DEPTH + ' '
signal.signal(signal.SIGPIPE, signal.SIG_DFL) # python ignores SIGPIPE
os.execvp(argv[0], argv)
assert(0)
# returns only if there's an exception
def after(t, rv):
return self._after2(rv)
jwack.start_job(self.t, run, after)
def _do_subproc(self):
# careful: REDO_PWD was the PWD relative to the STARTPATH at the time
# we *started* building the current target; but that target ran
# redo-ifchange, and it might have done it from a different directory
# than we started it in. So os.getcwd() might be != REDO_PWD right
# now.
assert(state.is_flushed())
dn = self.dodir
newp = os.path.realpath(dn)
os.environ['REDO_PWD'] = state.relpath(newp, vars.STARTDIR)
os.environ['REDO_TARGET'] = self.basename + self.ext
os.environ['REDO_DEPTH'] = vars.DEPTH + ' '
vars.add_lock(str(self.lock.fid))
if dn:
os.chdir(dn)
os.dup2(self.f.fileno(), 1)
os.close(self.f.fileno())
close_on_exec(1, False)
if vars.LOG:
cur_inode = str(os.fstat(2).st_ino)
if not vars.LOG_INODE or cur_inode == vars.LOG_INODE:
# .do script has *not* redirected stderr, which means we're
# using redo-log's log saving mode. That means subprocs
# should be logged to their own file. If the .do script
# *does* redirect stderr, that redirection should be inherited
# by subprocs, so we'd do nothing.
logf = open(state.logname(self.sf.id), 'w')
new_inode = str(os.fstat(logf.fileno()).st_ino)
os.environ['REDO_LOG'] = '1' # .do files can check this
os.environ['REDO_LOG_INODE'] = new_inode
os.dup2(logf.fileno(), 2)
close_on_exec(2, False)
logf.close()
else:
if 'REDO_LOG_INODE' in os.environ:
del os.environ['REDO_LOG_INODE']
os.environ['REDO_LOG'] = ''
signal.signal(signal.SIGPIPE, signal.SIG_DFL) # python ignores SIGPIPE
if vars.VERBOSE or vars.XTRACE:
logs.write('* %s' % ' '.join(self.argv).replace('\n', ' '))
os.execvp(self.argv[0], self.argv)
# FIXME: it would be nice to log the exit code to logf.
# But that would have to happen in the parent process, which doesn't
# have logf open.
assert(0)
# returns only if there's an exception
def _after(self, t, rv):
try:
state.check_sane()
rv = self._after1(t, rv)
state.commit()
finally:
self._after2(rv)
def _after1(self, t, rv):
f = self.f
before_t = self.before_t
after_t = _try_stat(t)
st1 = os.fstat(f.fileno())
st2 = _try_stat(self.tmpname2)
if (after_t and
(not before_t or before_t.st_mtime != after_t.st_mtime) and
not stat.S_ISDIR(after_t.st_mode)):
err('%s modified %s directly!\n' % (self.argv[2], t))
err('...you should update $3 (a temp file) or stdout, not $1.\n')
rv = 206
elif st2 and st1.st_size > 0:
err('%s wrote to stdout *and* created $3.\n' % self.argv[2])
err('...you should write status messages to stderr, not stdout.\n')
rv = 207
if rv==0:
if st2:
try:
os.rename(self.tmpname2, t)
except OSError, e:
dnt = os.path.dirname(t)
if not os.path.exists(dnt):
err('%s: target dir %r does not exist!\n' % (t, dnt))
else:
err('%s: rename %s: %s\n' % (t, self.tmpname2, e))
raise
os.unlink(self.tmpname1)
elif st1.st_size > 0:
try:
os.rename(self.tmpname1, t)
except OSError, e:
if e.errno == errno.ENOENT:
unlink(t)
else:
err('%s: can\'t save stdout to %r: %s\n' %
(self.argv[2], t, e.strerror))
rv = 1000
if st2:
os.unlink(self.tmpname2)
else: # no output generated at all; that's ok
unlink(self.tmpname1)
unlink(t)
sf = self.sf
sf.refresh()
sf.is_generated = True
sf.is_override = False
if sf.is_checked() or sf.is_changed():
# it got checked during the run; someone ran redo-stamp.
# update_stamp would call set_changed(); we don't want that,
# so only use read_stamp.
sf.stamp = sf.read_stamp()
else:
sf.csum = None
sf.update_stamp()
sf.set_changed()
else:
unlink(self.tmpname1)
unlink(self.tmpname2)
sf = self.sf
sf.set_failed()
sf.zap_deps2()
sf.save()
f.close()
meta('done', '%d %s' % (rv, state.target_relpath(self.t)))
return rv
def _after2(self, rv):
try:
self.donefunc(self.t, rv)
assert(self.lock.owned)
finally:
self.lock.unlock()
def main(targets, shouldbuildfunc):
retcode = [0] # a list so that it can be reassigned from done()
if vars.SHUFFLE:
import random
random.shuffle(targets)
locked = []
def done(t, rv):
if rv:
retcode[0] = 1
if vars.TARGET and not vars.UNLOCKED:
me = os.path.join(vars.STARTDIR,
os.path.join(vars.PWD, vars.TARGET))
myfile = state.File(name=me)
selflock = state.Lock(state.LOG_LOCK_MAGIC + myfile.id)
else:
selflock = myfile = me = None
def cheat():
if not selflock: return 0
selflock.trylock()
if not selflock.owned:
# redo-log already owns it: let's cheat.
# Give ourselves one extra token so that the "foreground" log
# can always make progress.
return 1
else:
# redo-log isn't watching us (yet)
selflock.unlock()
return 0
# In the first cycle, we just build as much as we can without worrying
# about any lock contention. If someone else has it locked, we move on.
seen = {}
lock = None
for t in targets:
if not t:
err('cannot build the empty target ("").\n')
retcode[0] = 204
break
assert(state.is_flushed())
if t in seen:
continue
seen[t] = 1
if not jwack.has_token():
state.commit()
jwack.ensure_token_or_cheat(t, cheat)
if retcode[0] and not vars.KEEP_GOING:
break
if not state.check_sane():
err('.redo directory disappeared; cannot continue.\n')
retcode[0] = 205
break
f = state.File(name=t)
lock = state.Lock(f.id)
if vars.UNLOCKED:
lock.owned = True
else:
lock.trylock()
if not lock.owned:
meta('locked', state.target_relpath(t))
locked.append((f.id,t,f.name))
else:
# We had to create f before we had a lock, because we need f.id
# to make the lock. But someone may have updated the state
# between then and now.
# FIXME: separate obtaining the fid from creating the File.
# FIXME: maybe integrate locking into the File object?
f.refresh()
BuildJob(t, f, lock, shouldbuildfunc, done).start()
state.commit()
assert(state.is_flushed())
lock = None
del lock
# Now we've built all the "easy" ones. Go back and just wait on the
# remaining ones one by one. There's no reason to do it any more
# efficiently, because if these targets were previously locked, that
# means someone else was building them; thus, we probably won't need to
# do anything. The only exception is if we're invoked as redo instead
# of redo-ifchange; then we have to redo it even if someone else already
# did. But that should be rare.
while locked or jwack.running():
state.commit()
jwack.wait_all()
assert jwack._mytokens == 0
jwack.ensure_token_or_cheat('self', cheat)
# at this point, we don't have any children holding any tokens, so
# it's okay to block below.
if retcode[0] and not vars.KEEP_GOING:
break
if locked:
if not state.check_sane():
err('.redo directory disappeared; cannot continue.\n')
retcode[0] = 205
break
fid,t,fname = locked.pop(0)
lock = state.Lock(fid)
backoff = 0.01
lock.trylock()
while not lock.owned:
# Don't spin with 100% CPU while we fight for the lock.
import random
time.sleep(random.random() * min(backoff, 1.0))
backoff *= 2
# after printing this line, redo-log will recurse into t,
# whether it's us building it, or someone else.
meta('waiting', state.target_relpath(t))
try:
lock.check()
except state.CyclicDependencyError:
err('cyclic dependency while building %s\n' % _nice(t))
retcode[0] = 208
return retcode[0]
# this sequence looks a little silly, but the idea is to
# give up our personal token while we wait for the lock to
# be released; but we should never run ensure_token() while
# holding a lock, or we could cause deadlocks.
jwack.release_mine()
lock.waitlock()
# now t is definitely free, so we get to decide whether
# to build it.
lock.unlock()
jwack.ensure_token_or_cheat(t, cheat)
lock.trylock()
assert(lock.owned)
meta('unlocked', state.target_relpath(t))
if state.File(name=t).is_failed():
err('%s: failed in another thread\n' % _nice(t))
retcode[0] = 2
lock.unlock()
else:
BuildJob(t, state.File(id=fid), lock,
shouldbuildfunc, done).start()
lock = None
state.commit()
return retcode[0]