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Kaydet (Commit) 172c40b2 authored tarafından Tim Peters's avatar Tim Peters
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Whitespace normalization.

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Demo/threads/bug.py
Dosyayı görüntüle @ 172c40b2
# The following self-contained little program usually freezes with most
# threads reporting
#
#
# Unhandled exception in thread:
# Traceback (innermost last):
# File "importbug.py", line 6
# x = whrandom.randint(1,3)
# AttributeError: randint
#
#
# Here's the program; it doesn't use anything from the attached module:
import thread
......@@ -33,37 +33,37 @@ print 'done'
# Sticking an acquire/release pair around the 'import' statement makes the
# problem go away.
#
#
# I believe that what happens is:
#
#
# 1) The first thread to hit the import atomically reaches, and executes
# most of, get_module. In particular, it finds Lib/whrandom.pyc,
# installs its name in sys.modules, and executes
#
#
# v = eval_code(co, d, d, d, (object *)NULL);
#
#
# to initialize the module.
#
#
# 2) eval_code "ticker"-slices the 1st thread out, and gives another thread
# a chance. When this 2nd thread hits the same 'import', import_module
# finds 'whrandom' in sys.modules, so just proceeds.
#
#
# 3) But the 1st thread is still "in the middle" of executing whrandom.pyc.
# So the 2nd thread has a good chance of trying to look up 'randint'
# before the 1st thread has placed it in whrandom's dict.
#
#
# 4) The more threads there are, the more likely that at least one of them
# will do this before the 1st thread finishes the import work.
#
#
# If that's right, a perhaps not-too-bad workaround would be to introduce a
# static "you can't interrupt this thread" flag in ceval.c, check it before
# giving up interpreter_lock, and have IMPORT_NAME set it & restore (plain
# clearing would not work) it around its call to import_module. To its
# credit, there's something wonderfully perverse about fixing a race via an
# unprotected static <grin>.
#
#
# as-with-most-other-things-(pseudo-)parallel-programming's-more-fun-
# in-python-too!-ly y'rs - tim
#
#
# Tim Peters tim@ksr.com
# not speaking for Kendall Square Research Corp
Demo/threads/find.py
Dosyayı görüntüle @ 172c40b2
......@@ -32,121 +32,121 @@ import thread
class WorkQ:
# Invariants:
# - busy and work are only modified when mutex is locked
# - len(work) is the number of jobs ready to be taken
# - busy is the number of jobs being done
# - todo is locked iff there is no work and somebody is busy
def __init__(self):
self.mutex = thread.allocate()
self.todo = thread.allocate()
self.todo.acquire()
self.work = []
self.busy = 0
def addwork(self, func, args):
job = (func, args)
self.mutex.acquire()
self.work.append(job)
self.mutex.release()
if len(self.work) == 1:
self.todo.release()
def _getwork(self):
self.todo.acquire()
self.mutex.acquire()
if self.busy == 0 and len(self.work) == 0:
self.mutex.release()
self.todo.release()
return None
job = self.work[0]
del self.work[0]
self.busy = self.busy + 1
self.mutex.release()
if len(self.work) > 0:
self.todo.release()
return job
def _donework(self):
self.mutex.acquire()
self.busy = self.busy - 1
if self.busy == 0 and len(self.work) == 0:
self.todo.release()
self.mutex.release()
def _worker(self):
time.sleep(0.00001) # Let other threads run
while 1:
job = self._getwork()
if not job:
break
func, args = job
apply(func, args)
self._donework()
def run(self, nworkers):
if not self.work:
return # Nothing to do
for i in range(nworkers-1):
thread.start_new(self._worker, ())
self._worker()
self.todo.acquire()
# Invariants:
# - busy and work are only modified when mutex is locked
# - len(work) is the number of jobs ready to be taken
# - busy is the number of jobs being done
# - todo is locked iff there is no work and somebody is busy
def __init__(self):
self.mutex = thread.allocate()
self.todo = thread.allocate()
self.todo.acquire()
self.work = []
self.busy = 0
def addwork(self, func, args):
job = (func, args)
self.mutex.acquire()
self.work.append(job)
self.mutex.release()
if len(self.work) == 1:
self.todo.release()
def _getwork(self):
self.todo.acquire()
self.mutex.acquire()
if self.busy == 0 and len(self.work) == 0:
self.mutex.release()
self.todo.release()
return None
job = self.work[0]
del self.work[0]
self.busy = self.busy + 1
self.mutex.release()
if len(self.work) > 0:
self.todo.release()
return job
def _donework(self):
self.mutex.acquire()
self.busy = self.busy - 1
if self.busy == 0 and len(self.work) == 0:
self.todo.release()
self.mutex.release()
def _worker(self):
time.sleep(0.00001) # Let other threads run
while 1:
job = self._getwork()
if not job:
break
func, args = job
apply(func, args)
self._donework()
def run(self, nworkers):
if not self.work:
return # Nothing to do
for i in range(nworkers-1):
thread.start_new(self._worker, ())
self._worker()
self.todo.acquire()
# Main program
def main():
sys.argv.append("/tmp")
nworkers = 4
opts, args = getopt.getopt(sys.argv[1:], '-w:')
for opt, arg in opts:
if opt == '-w':
nworkers = string.atoi(arg)
if not args:
args = [os.curdir]
sys.argv.append("/tmp")
nworkers = 4
opts, args = getopt.getopt(sys.argv[1:], '-w:')
for opt, arg in opts:
if opt == '-w':
nworkers = string.atoi(arg)
if not args:
args = [os.curdir]
wq = WorkQ()
for dir in args:
wq.addwork(find, (dir, selector, wq))
wq = WorkQ()
for dir in args:
wq.addwork(find, (dir, selector, wq))
t1 = time.time()
wq.run(nworkers)
t2 = time.time()
t1 = time.time()
wq.run(nworkers)
t2 = time.time()
sys.stderr.write('Total time ' + `t2-t1` + ' sec.\n')
sys.stderr.write('Total time ' + `t2-t1` + ' sec.\n')
# The predicate -- defines what files we look for.
# Feel free to change this to suit your purpose
def selector(dir, name, fullname, stat):
# Look for group or world writable files
return (stat[ST_MODE] & 0022) != 0
# Look for group or world writable files
return (stat[ST_MODE] & 0022) != 0
# The find procedure -- calls wq.addwork() for subdirectories
def find(dir, pred, wq):
try:
names = os.listdir(dir)
except os.error, msg:
print `dir`, ':', msg
return
for name in names:
if name not in (os.curdir, os.pardir):
fullname = os.path.join(dir, name)
try:
stat = os.lstat(fullname)
except os.error, msg:
print `fullname`, ':', msg
continue
if pred(dir, name, fullname, stat):
print fullname
if S_ISDIR(stat[ST_MODE]):
if not os.path.ismount(fullname):
wq.addwork(find, (fullname, pred, wq))
try:
names = os.listdir(dir)
except os.error, msg:
print `dir`, ':', msg
return
for name in names:
if name not in (os.curdir, os.pardir):
fullname = os.path.join(dir, name)
try:
stat = os.lstat(fullname)
except os.error, msg:
print `fullname`, ':', msg
continue
if pred(dir, name, fullname, stat):
print fullname
if S_ISDIR(stat[ST_MODE]):
if not os.path.ismount(fullname):
wq.addwork(find, (fullname, pred, wq))
# Call the main program
......
Demo/threads/telnet.py
Dosyayı görüntüle @ 172c40b2
......@@ -21,94 +21,94 @@ BUFSIZE = 8*1024
# Telnet protocol characters
IAC = chr(255) # Interpret as command
IAC = chr(255) # Interpret as command
DONT = chr(254)
DO = chr(253)
WONT = chr(252)
WILL = chr(251)
def main():
if len(sys.argv) < 2:
sys.stderr.write('usage: telnet hostname [port]\n')
sys.exit(2)
host = sys.argv[1]
try:
hostaddr = gethostbyname(host)
except error:
sys.stderr.write(sys.argv[1] + ': bad host name\n')
sys.exit(2)
#
if len(sys.argv) > 2:
servname = sys.argv[2]
else:
servname = 'telnet'
#
if '0' <= servname[:1] <= '9':
port = eval(servname)
else:
try:
port = getservbyname(servname, 'tcp')
except error:
sys.stderr.write(servname + ': bad tcp service name\n')
sys.exit(2)
#
s = socket(AF_INET, SOCK_STREAM)
#
try:
s.connect((host, port))
except error, msg:
sys.stderr.write('connect failed: ' + `msg` + '\n')
sys.exit(1)
#
thread.start_new(child, (s,))
parent(s)
if len(sys.argv) < 2:
sys.stderr.write('usage: telnet hostname [port]\n')
sys.exit(2)
host = sys.argv[1]
try:
hostaddr = gethostbyname(host)
except error:
sys.stderr.write(sys.argv[1] + ': bad host name\n')
sys.exit(2)
#
if len(sys.argv) > 2:
servname = sys.argv[2]
else:
servname = 'telnet'
#
if '0' <= servname[:1] <= '9':
port = eval(servname)
else:
try:
port = getservbyname(servname, 'tcp')
except error:
sys.stderr.write(servname + ': bad tcp service name\n')
sys.exit(2)
#
s = socket(AF_INET, SOCK_STREAM)
#
try:
s.connect((host, port))
except error, msg:
sys.stderr.write('connect failed: ' + `msg` + '\n')
sys.exit(1)
#
thread.start_new(child, (s,))
parent(s)
def parent(s):
# read socket, write stdout
iac = 0 # Interpret next char as command
opt = '' # Interpret next char as option
while 1:
data, dummy = s.recvfrom(BUFSIZE)
if not data:
# EOF -- exit
sys.stderr.write( '(Closed by remote host)\n')
sys.exit(1)
cleandata = ''
for c in data:
if opt:
print ord(c)
## print '(replying: ' + `opt+c` + ')'
s.send(opt + c)
opt = ''
elif iac:
iac = 0
if c == IAC:
cleandata = cleandata + c
elif c in (DO, DONT):
if c == DO: print '(DO)',
else: print '(DONT)',
opt = IAC + WONT
elif c in (WILL, WONT):
if c == WILL: print '(WILL)',
else: print '(WONT)',
opt = IAC + DONT
else:
print '(command)', ord(c)
elif c == IAC:
iac = 1
print '(IAC)',
else:
cleandata = cleandata + c
sys.stdout.write(cleandata)
sys.stdout.flush()
## print 'Out:', `cleandata`
# read socket, write stdout
iac = 0 # Interpret next char as command
opt = '' # Interpret next char as option
while 1:
data, dummy = s.recvfrom(BUFSIZE)
if not data:
# EOF -- exit
sys.stderr.write( '(Closed by remote host)\n')
sys.exit(1)
cleandata = ''
for c in data:
if opt:
print ord(c)
## print '(replying: ' + `opt+c` + ')'
s.send(opt + c)
opt = ''
elif iac:
iac = 0
if c == IAC:
cleandata = cleandata + c
elif c in (DO, DONT):
if c == DO: print '(DO)',
else: print '(DONT)',
opt = IAC + WONT
elif c in (WILL, WONT):
if c == WILL: print '(WILL)',
else: print '(WONT)',
opt = IAC + DONT
else:
print '(command)', ord(c)
elif c == IAC:
iac = 1
print '(IAC)',
else:
cleandata = cleandata + c
sys.stdout.write(cleandata)
sys.stdout.flush()
## print 'Out:', `cleandata`
def child(s):
# read stdin, write socket
while 1:
line = sys.stdin.readline()
## print 'Got:', `line`
if not line: break
s.send(line)
# read stdin, write socket
while 1:
line = sys.stdin.readline()
## print 'Got:', `line`
if not line: break
s.send(line)
main()
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