> diff -r 8089902215a5 Doc/library/_thread.rst
> --- a/Doc/library/_thread.rst Fri Jan 08 18:54:23 2010 +0100
> +++ b/Doc/library/_thread.rst Fri Jan 08 20:33:54 2010 +0100
> @@ -103,18 +103,29 @@ It defines the following constant and fu
> Availability: Windows, systems with POSIX threads.
>
>
> +.. data:: TIMEOUT_MAX
Above here, it says, "It defines the following constant and
functions:", which should be updated to "constants" now that there are
2.
> +
> + The maximum value allowed for the *timeout* parameter of
> + :meth:`Lock.acquire`. Specifiying a timeout greater than this value will
> + raise an :exc:`OverflowError`.
Do we want to document what this value is likely to be? Or guarantee
that it's at least 2000?
I believe we can support arbitrary values here, subject to floating
point rounding errors, by calling lock-with-timeout in a loop. I'm not
sure whether that's a good idea, but it fits better with python's
arbitrary-precision ints.
> +
> +
> Lock objects have the following methods:
>
>
> -.. method:: lock.acquire([waitflag])
> +.. method:: lock.acquire(waitflag=1, timeout=-1)
>
> Without the optional argument, this method acquires the lock
> unconditionally, if
Since there are now 2 optional arguments, this needs to be updated.
> necessary waiting until it is released by another thread (only one
> thread at a
> time can acquire a lock --- that's their reason for existence).
> If the integer
> *waitflag* argument is present, the action depends on its value:
> if it is zero,
> the lock is only acquired if it can be acquired immediately without waiting,
> - while if it is nonzero, the lock is acquired unconditionally as before. The
> - return value is ``True`` if the lock is acquired successfully,
> ``False`` if not.
> + while if it is nonzero, the lock is acquired unconditionally as before.
> + If the floating-point *timeout* argument is present and positive, it
> + specifies the maximum wait time in seconds before returning.
You might mention that "lock.acquire(timeout=0)" is equivalent to
"lock.acquire(waitflag=0)", and that a missing or negative timeout
causes an unbounded wait.
> +
> + The return value is ``True`` if the lock is acquired successfully,
> + ``False`` if not.
>
>
> .. method:: lock.release()
> diff -r 8089902215a5 Doc/library/threading.rst
> --- a/Doc/library/threading.rst Fri Jan 08 18:54:23 2010 +0100
> +++ b/Doc/library/threading.rst Fri Jan 08 20:33:54 2010 +0100
> @@ -155,6 +155,16 @@ This module defines the following functi
> Availability: Windows, systems with POSIX threads.
>
>
> +This module also defines the following constant:
> +
> +.. data:: TIMEOUT_MAX
> +
> + The maximum value allowed for the *timeout* parameter of blocking functions
> + (:meth:`Lock.acquire`, :meth:`RLock.acquire`, :meth:`Condition.wait`, etc.).
> + Specifiying a timeout greater than this value will raise an
> + :exc:`OverflowError`.
> +
> +
> Detailed interfaces for the objects are documented below.
>
> The design of this module is loosely based on Java's threading model. However,
> @@ -349,7 +359,7 @@ and may vary across implementations.
> All methods are executed atomically.
>
>
> -.. method:: Lock.acquire(blocking=True)
> +.. method:: Lock.acquire(blocking=True, timeout=-1)
>
> Acquire a lock, blocking or non-blocking.
>
> @@ -363,6 +373,13 @@ All methods are executed atomically.
> without an argument would block, return false immediately; otherwise, do the
> same thing as when called without arguments, and return true.
>
> + When invoked with the floating-point *timeout* argument set to a positive
> + value, block for at most the number of seconds specified by *timeout*
> + and as long as the lock cannot be acquired.
s/and as long as the lock cannot be acquired./and return False if the
lock couldn't be acquired by then./ ? Also consider an equivalent
comment about timeout<=0 as I suggested for _thread.
> +
> + The return value is ``True`` if the lock is acquired successfully,
> + ``False`` if not.
> +
>
> .. method:: Lock.release()
>
> @@ -396,7 +413,7 @@ pair) resets the lock to unlocked and al
> :meth:`acquire` to proceed.
>
>
> -.. method:: RLock.acquire(blocking=True)
> +.. method:: RLock.acquire(blocking=True, timeout=-1)
>
> Acquire a lock, blocking or non-blocking.
>
> @@ -415,6 +432,11 @@ pair) resets the lock to unlocked and al
> without an argument would block, return false immediately; otherwise, do the
> same thing as when called without arguments, and return true.
>
> + When invoked with the floating-point *timeout* argument set to a positive
> + value, block for at most the number of seconds specified by *timeout*
> + and as long as the lock cannot be acquired. Return true if the lock has
> + been acquired, false if the timeout has elapsed.
``True`` and ``False``? And same comment as for Lock.acquire.
> +
>
> .. method:: RLock.release()
>
> diff -r 8089902215a5 Include/pythread.h
> --- a/Include/pythread.h Fri Jan 08 18:54:23 2010 +0100
> +++ b/Include/pythread.h Fri Jan 08 20:33:54 2010 +0100
> @@ -23,6 +23,30 @@ PyAPI_FUNC(void) PyThread_free_lock(PyTh
> PyAPI_FUNC(int) PyThread_acquire_lock(PyThread_type_lock, int);
> #define WAIT_LOCK 1
> #define NOWAIT_LOCK 0
> +
> +#if defined(HAVE_LONG_LONG)
> +#define PY_TIMEOUT_T PY_LONG_LONG
> +#define PY_TIMEOUT_MAX PY_LLONG_MAX
I think this deserves a comment that it's not the same as
_thread.TIMEOUT_MAX and why.
> +#else
> +#define PY_TIMEOUT_T long
> +#define PY_TIMEOUT_MAX LONG_MAX
> +#endif
> +
> +/* In the NT API, the timeout is a DWORD and is expressed in milliseconds */
> +#if defined (NT_THREADS) && (0xFFFFFFFFLL * 1000 < PY_TIMEOUT_MAX)
> +#undef PY_TIMEOUT_MAX
> +#define PY_TIMEOUT_MAX (0xFFFFFFFFLL * 1000)
> +#endif
> +
> +/* If microseconds == 0, the call is non-blocking: it returns immediately
> + even when the lock can't be acquired.
> + If microseconds > 0, the call waits up to the specified duration.
> + If microseconds < 0, the call waits until success (or abnormal failure)
> +
> + microseconds must be less than PY_TIMEOUT_MAX. Behaviour otherwise is
> + undefined. */
> +PyAPI_FUNC(int) PyThread_acquire_lock_timed(PyThread_type_lock,
> + PY_TIMEOUT_T microseconds);
> PyAPI_FUNC(void) PyThread_release_lock(PyThread_type_lock);
>
> PyAPI_FUNC(size_t) PyThread_get_stacksize(void);
> diff -r 8089902215a5 Lib/_dummy_thread.py
> --- a/Lib/_dummy_thread.py Fri Jan 08 18:54:23 2010 +0100
> +++ b/Lib/_dummy_thread.py Fri Jan 08 20:33:54 2010 +0100
> @@ -17,6 +17,10 @@ __all__ = ['error', 'start_new_thread',
> 'interrupt_main', 'LockType']
>
> import traceback as _traceback
> +import time
> +
> +# A dummy value
> +TIMEOUT_MAX = 2**31
This should probably be the same as the typical value for _thread.TIMEOUT_MAX.
> class error(Exception):
> """Dummy implementation of _thread.error."""
> @@ -92,7 +96,7 @@ class LockType(object):
> def __init__(self):
> self.locked_status = False
>
> - def acquire(self, waitflag=None):
> + def acquire(self, waitflag=None, timeout=-1):
> """Dummy implementation of acquire().
>
> For blocking calls, self.locked_status is automatically set to
> @@ -111,6 +115,8 @@ class LockType(object):
> self.locked_status = True
> return True
> else:
> + if timeout > 0:
> + time.sleep(timeout)
> return False
>
> __enter__ = acquire
> diff -r 8089902215a5 Lib/multiprocessing/pool.py
> --- a/Lib/multiprocessing/pool.py Fri Jan 08 18:54:23 2010 +0100
> +++ b/Lib/multiprocessing/pool.py Fri Jan 08 20:33:54 2010 +0100
> @@ -379,10 +379,10 @@ class Pool(object):
> p.terminate()
>
> debug('joining task handler')
> - task_handler.join(1e100)
> + task_handler.join()
Why is this change here? (Mostly curiosity)
>
> debug('joining result handler')
> - result_handler.join(1e100)
> + task_handler.join()
>
> if pool and hasattr(pool[0], 'terminate'):
> debug('joining pool workers')
> diff -r 8089902215a5 Lib/test/lock_tests.py
> --- a/Lib/test/lock_tests.py Fri Jan 08 18:54:23 2010 +0100
> +++ b/Lib/test/lock_tests.py Fri Jan 08 20:33:54 2010 +0100
> @@ -4,7 +4,7 @@ Various tests for synchronization primit
>
> import sys
> import time
> -from _thread import start_new_thread, get_ident
> +from _thread import start_new_thread, get_ident, TIMEOUT_MAX
> import threading
> import unittest
>
> @@ -62,6 +62,14 @@ class BaseTestCase(unittest.TestCase):
> support.threading_cleanup(*self._threads)
> support.reap_children()
>
> + def assertTimeout(self, actual, expected):
> + # The waiting and/or time.time() can be imprecise, which
> + # is why comparing to the expected value would sometimes fail
> + # (especially under Windows).
> + self.assertGreaterEqual(actual, expected * 0.6)
> + # Test nothing insane happened
> + self.assertLess(actual, expected * 10.0)
> +
>
> class BaseLockTests(BaseTestCase):
> """
> @@ -143,6 +151,31 @@ class BaseLockTests(BaseTestCase):
> Bunch(f, 15).wait_for_finished()
> self.assertEqual(n, len(threading.enumerate()))
>
> + def test_timeout(self):
> + lock = self.locktype()
> + # Can't set timeout if not blocking
Please add this to the documentation.
> + self.assertRaises(ValueError, lock.acquire, 0, 1)
> + # Invalid timeout values
> + self.assertRaises(ValueError, lock.acquire, timeout=-100)
> + self.assertRaises(OverflowError, lock.acquire, timeout=1e100)
> + self.assertRaises(OverflowError, lock.acquire, timeout=TIMEOUT_MAX + 1)
> + # TIMEOUT_MAX is ok
> + lock.acquire(timeout=TIMEOUT_MAX)
> + lock.release()
> + t1 = time.time()
> + self.assertTrue(lock.acquire(timeout=5))
> + t2 = time.time()
> + self.assertLess(t2 - t1, 5)
This is just a sanity-check that a successful acquire finishes in a
sane amount of time, right? Please comment that.
> + results = []
> + def f():
> + t1 = time.time()
> + results.append(lock.acquire(timeout=0.5))
> + t2 = time.time()
> + results.append(t2 - t1)
> + Bunch(f, 1).wait_for_finished()
> + self.assertFalse(results[0])
> + self.assertTimeout(results[1], 0.5)
> +
>
> class LockTests(BaseLockTests):
> """
> @@ -178,7 +211,7 @@ class LockTests(BaseLockTests):
> b.wait_for_finished()
> lock.acquire()
> lock.release()
> -
> +
>
> class RLockTests(BaseLockTests):
> """
> @@ -284,14 +317,14 @@ class EventTests(BaseTestCase):
> def f():
> results1.append(evt.wait(0.0))
> t1 = time.time()
> - r = evt.wait(0.2)
> + r = evt.wait(0.5)
> t2 = time.time()
> results2.append((r, t2 - t1))
> Bunch(f, N).wait_for_finished()
> self.assertEqual(results1, [False] * N)
> for r, dt in results2:
> self.assertFalse(r)
> - self.assertTrue(dt >= 0.2, dt)
> + self.assertTimeout(dt, 0.5)
> # The event is set
> results1 = []
> results2 = []
> @@ -397,14 +430,14 @@ class ConditionTests(BaseTestCase):
> def f():
> cond.acquire()
> t1 = time.time()
> - cond.wait(0.2)
> + cond.wait(0.5)
> t2 = time.time()
> cond.release()
> results.append(t2 - t1)
> Bunch(f, N).wait_for_finished()
> self.assertEqual(len(results), 5)
> for dt in results:
> - self.assertTrue(dt >= 0.2, dt)
> + self.assertTimeout(dt, 0.5)
>
>
> class BaseSemaphoreTests(BaseTestCase):
> diff -r 8089902215a5 Lib/threading.py
> --- a/Lib/threading.py Fri Jan 08 18:54:23 2010 +0100
> +++ b/Lib/threading.py Fri Jan 08 20:33:54 2010 +0100
> @@ -31,6 +31,7 @@ try:
> _CRLock = _thread.RLock
> except AttributeError:
> _CRLock = None
> +TIMEOUT_MAX = _thread.TIMEOUT_MAX
> del _thread
>
>
> @@ -107,14 +108,14 @@ class _RLock(_Verbose):
> return "<%s owner=%r count=%d>" % (
> self.__class__.__name__, owner, self._count)
>
> - def acquire(self, blocking=True):
> + def acquire(self, blocking=True, timeout=-1):
> me = _get_ident()
> if self._owner == me:
> self._count = self._count + 1
> if __debug__:
> self._note("%s.acquire(%s): recursive success", self, blocking)
> return 1
> - rc = self._block.acquire(blocking)
> + rc = self._block.acquire(blocking, timeout)
> if rc:
> self._owner = me
> self._count = 1
> @@ -234,22 +235,10 @@ class _Condition(_Verbose):
> if __debug__:
> self._note("%s.wait(): got it", self)
> else:
> - # Balancing act: We can't afford a pure busy loop, so we
> - # have to sleep; but if we sleep the whole timeout time,
> - # we'll be unresponsive. The scheme here sleeps very
> - # little at first, longer as time goes on, but never longer
> - # than 20 times per second (or the timeout time remaining).
> - endtime = _time() + timeout
> - delay = 0.0005 # 500 us -> initial delay of 1 ms
> - while True:
> - gotit = waiter.acquire(0)
> - if gotit:
> - break
> - remaining = endtime - _time()
> - if remaining <= 0:
> - break
> - delay = min(delay * 2, remaining, .05)
> - _sleep(delay)
> + if timeout > 0:
> + gotit = waiter.acquire(True, timeout)
> + else:
> + gotit = waiter.acquire(False)
> if not gotit:
> if __debug__:
> self._note("%s.wait(%s): timed out", self, timeout)
> diff -r 8089902215a5 Modules/_threadmodule.c
> --- a/Modules/_threadmodule.c Fri Jan 08 18:54:23 2010 +0100
> +++ b/Modules/_threadmodule.c Fri Jan 08 20:33:54 2010 +0100
> @@ -39,18 +39,47 @@ lock_dealloc(lockobject *self)
> }
>
> static PyObject *
> -lock_PyThread_acquire_lock(lockobject *self, PyObject *args)
> +lock_PyThread_acquire_lock(lockobject *self, PyObject *args, PyObject *kwds)
> {
> - int i = 1;
> + char *kwlist[] = {"blocking", "timeout", NULL};
> + int blocking = 1;
> + double timeout = -1;
> + PY_TIMEOUT_T microseconds;
> + int r;
>
> - if (!PyArg_ParseTuple(args, "|i:acquire", &i))
> + if (!PyArg_ParseTupleAndKeywords(args, kwds, "|id:acquire", kwlist,
> + &blocking, &timeout))
> return NULL;
>
> + if (!blocking && timeout != -1) {
> + PyErr_SetString(PyExc_ValueError, "can't specify a timeout "
> + "for a non-blocking call");
> + return NULL;
> + }
> + if (timeout < 0 && timeout != -1) {
> + PyErr_SetString(PyExc_ValueError, "timeout value must be "
> + "strictly positive");
> + return NULL;
> + }
> + if (!blocking)
> + microseconds = 0;
> + else if (timeout == -1)
> + microseconds = -1;
> + else {
> + timeout *= 1e6;
> + if (timeout > PY_TIMEOUT_MAX) {
I believe it's possible for this comparison to return false, but for
the conversion to PY_TIMEOUT_T to still overflow:
$ cat test.c
#include <stdio.h>
#include <limits.h>
int main() {
double d_ll_max = (double)LONG_LONG_MAX;
if (d_ll_max > LONG_LONG_MAX)
printf("Bigger\n");
if (d_ll_max == LONG_LONG_MAX)
printf("Equal\n");
printf("%lld %lf %lld\n", LONG_LONG_MAX, d_ll_max, (long long)d_ll_max);
return 0;
}
$ ./test
Equal
9223372036854775807 9223372036854775808.000000 -9223372036854775808
Unfortunately, that overflowing cast back to long long is undefined
behavior, and I don't know how to check for that overflow before it
happens.
> + PyErr_SetString(PyExc_OverflowError,
> + "timeout value is too large");
> + return NULL;
> + }
> + microseconds = (PY_TIMEOUT_T) timeout;
> + }
> +
> Py_BEGIN_ALLOW_THREADS
> - i = PyThread_acquire_lock(self->lock_lock, i);
> + r = PyThread_acquire_lock_timed(self->lock_lock, microseconds);
> Py_END_ALLOW_THREADS
>
> - return PyBool_FromLong((long)i);
> + return PyBool_FromLong(r);
> }
>
> PyDoc_STRVAR(acquire_doc,
> @@ -105,9 +134,9 @@ Return whether the lock is in the locked
>
> static PyMethodDef lock_methods[] = {
> {"acquire_lock", (PyCFunction)lock_PyThread_acquire_lock,
> - METH_VARARGS, acquire_doc},
> + METH_VARARGS | METH_KEYWORDS, acquire_doc},
> {"acquire", (PyCFunction)lock_PyThread_acquire_lock,
> - METH_VARARGS, acquire_doc},
> + METH_VARARGS | METH_KEYWORDS, acquire_doc},
> {"release_lock", (PyCFunction)lock_PyThread_release_lock,
> METH_NOARGS, release_doc},
> {"release", (PyCFunction)lock_PyThread_release_lock,
> @@ -117,7 +146,7 @@ static PyMethodDef lock_methods[] = {
> {"locked", (PyCFunction)lock_locked_lock,
> METH_NOARGS, locked_doc},
> {"__enter__", (PyCFunction)lock_PyThread_acquire_lock,
> - METH_VARARGS, acquire_doc},
> + METH_VARARGS | METH_KEYWORDS, acquire_doc},
> {"__exit__", (PyCFunction)lock_PyThread_release_lock,
> METH_VARARGS, release_doc},
> {NULL, NULL} /* sentinel */
> @@ -182,15 +211,41 @@ rlock_dealloc(rlockobject *self)
> static PyObject *
> rlock_acquire(rlockobject *self, PyObject *args, PyObject *kwds)
> {
> - char *kwlist[] = {"blocking", NULL};
> + char *kwlist[] = {"blocking", "timeout", NULL};
> int blocking = 1;
> + double timeout = -1;
> + PY_TIMEOUT_T microseconds;
> long tid;
> int r = 1;
>
> - if (!PyArg_ParseTupleAndKeywords(args, kwds, "|i:acquire", kwlist,
> - &blocking))
> + if (!PyArg_ParseTupleAndKeywords(args, kwds, "|id:acquire", kwlist,
> + &blocking, &timeout))
> return NULL;
>
> + if (!blocking && timeout != -1) {
> + PyErr_SetString(PyExc_ValueError, "can't specify a timeout "
> + "for a non-blocking call");
> + return NULL;
> + }
> + if (timeout < 0 && timeout != -1) {
> + PyErr_SetString(PyExc_ValueError, "timeout value must be "
> + "strictly positive");
> + return NULL;
> + }
> + if (!blocking)
> + microseconds = 0;
> + else if (timeout == -1)
> + microseconds = -1;
> + else {
> + timeout *= 1e6;
> + if (timeout > PY_TIMEOUT_MAX) {
> + PyErr_SetString(PyExc_OverflowError,
> + "timeout value is too large");
> + return NULL;
> + }
> + microseconds = (PY_TIMEOUT_T) timeout;
> + }
> +
> tid = PyThread_get_thread_ident();
> if (self->rlock_count > 0 && tid == self->rlock_owner) {
> unsigned long count = self->rlock_count + 1;
> @@ -205,11 +260,11 @@ rlock_acquire(rlockobject *self, PyObjec
>
> if (self->rlock_count > 0 ||
> !PyThread_acquire_lock(self->rlock_lock, 0)) {
> - if (!blocking) {
> + if (microseconds == 0) {
> Py_RETURN_FALSE;
> }
> Py_BEGIN_ALLOW_THREADS
> - r = PyThread_acquire_lock(self->rlock_lock, blocking);
> + r = PyThread_acquire_lock_timed(self->rlock_lock, microseconds);
> Py_END_ALLOW_THREADS
> }
> if (r) {
> @@ -1012,7 +1067,7 @@ static struct PyModuleDef threadmodule =
> PyMODINIT_FUNC
> PyInit__thread(void)
> {
> - PyObject *m, *d;
> + PyObject *m, *d, *timeout_max;
>
> /* Initialize types: */
> if (PyType_Ready(&localtype) < 0)
> @@ -1027,6 +1082,12 @@ PyInit__thread(void)
> if (m == NULL)
> return NULL;
>
> + timeout_max = PyFloat_FromDouble(PY_TIMEOUT_MAX / 1000000.);
> + if (!timeout_max)
> + return NULL;
> + if (PyModule_AddObject(m, "TIMEOUT_MAX", timeout_max) < 0)
> + return NULL;
> +
> /* Add a symbolic constant */
> d = PyModule_GetDict(m);
> ThreadError = PyErr_NewException("_thread.error", NULL, NULL);
> diff -r 8089902215a5 Python/thread_nt.h
> --- a/Python/thread_nt.h Fri Jan 08 18:54:23 2010 +0100
> +++ b/Python/thread_nt.h Fri Jan 08 20:33:54 2010 +0100
> @@ -34,13 +34,13 @@ DeleteNonRecursiveMutex(PNRMUTEX mutex)
> }
>
> DWORD
> -EnterNonRecursiveMutex(PNRMUTEX mutex, BOOL wait)
> +EnterNonRecursiveMutex(PNRMUTEX mutex, DWORD milliseconds)
> {
> /* Assume that the thread waits successfully */
> DWORD ret ;
>
> /* InterlockedIncrement(&mutex->owned) == 0 means that no thread
> currently owns the mutex */
> - if (!wait)
> + if (!milliseconds)
Use ==0 now that this in a real integer?
> {
> if (InterlockedCompareExchange(&mutex->owned, 0, -1) != -1)
> return WAIT_TIMEOUT ;
> @@ -49,7 +49,7 @@ EnterNonRecursiveMutex(PNRMUTEX mutex, B
> else
> ret = InterlockedIncrement(&mutex->owned) ?
> /* Some thread owns the mutex, let's wait... */
> - WaitForSingleObject(mutex->hevent, INFINITE) : WAIT_OBJECT_0 ;
> + WaitForSingleObject(mutex->hevent, milliseconds) : WAIT_OBJECT_0 ;
>
> mutex->thread_id = GetCurrentThreadId() ; /* We own it */
> return ret ;
> @@ -249,17 +249,34 @@ PyThread_free_lock(PyThread_type_lock aL
> * if the lock has already been acquired by this thread!
> */
> int
> +PyThread_acquire_lock_timed(PyThread_type_lock aLock, PY_TIMEOUT_T
> microseconds)
> +{
> + int success ;
> + PY_TIMEOUT_T milliseconds;
> +
> + if (microseconds >= 0) {
> + milliseconds = (microseconds + 999) / 1000;
Can (microseconds+999) overflow?
> + if ((DWORD) milliseconds != milliseconds)
> + Py_FatalError("Timeout too large for a DWORD, "
> + "please check PY_TIMEOUT_MAX");
> + }
> + else
> + milliseconds = INFINITE;
> +
> + dprintf(("%ld: PyThread_acquire_lock_timed(%p, %lld) called\n",
> + PyThread_get_thread_ident(), aLock, microseconds));
> +
> + success = aLock && EnterNonRecursiveMutex((PNRMUTEX) aLock, (DWORD)
> milliseconds) == WAIT_OBJECT_0 ;
> +
> + dprintf(("%ld: PyThread_acquire_lock(%p, %lld) -> %d\n",
> + PyThread_get_thread_ident(), aLock, microseconds, success));
> +
> + return success;
> +}
> +int
> PyThread_acquire_lock(PyThread_type_lock aLock, int waitflag)
> {
> - int success ;
> -
> - dprintf(("%ld: PyThread_acquire_lock(%p, %d) called\n",
> PyThread_get_thread_ident(),aLock, waitflag));
> -
> - success = aLock && EnterNonRecursiveMutex((PNRMUTEX) aLock,
> (waitflag ? INFINITE : 0)) == WAIT_OBJECT_0 ;
> -
> - dprintf(("%ld: PyThread_acquire_lock(%p, %d) -> %d\n",
> PyThread_get_thread_ident(),aLock, waitflag, success));
> -
> - return success;
> + return PyThread_acquire_lock_timed(aLock, waitflag ? -1 : 0);
> }
>
> void
> diff -r 8089902215a5 Python/thread_pthread.h
> --- a/Python/thread_pthread.h Fri Jan 08 18:54:23 2010 +0100
> +++ b/Python/thread_pthread.h Fri Jan 08 20:33:54 2010 +0100
> @@ -83,6 +83,14 @@
> #endif
>
>
> +/* We assume all modern POSIX systems have gettimeofday() */
Famous last words. ;) (Not saying you should change anything)
> +#ifdef GETTIMEOFDAY_NO_TZ
> +#define GETTIMEOFDAY(ptv) gettimeofday(ptv)
> +#else
> +#define GETTIMEOFDAY(ptv) gettimeofday(ptv, (struct timezone *)NULL)
> +#endif
> +
> +
> /* A pthread mutex isn't sufficient to model the Python lock type
> * because, according to Draft 5 of the docs (P1003.4a/D5), both of the
> * following are undefined:
> @@ -335,34 +343,61 @@ fix_status(int status)
> return (status == -1) ? errno : status;
> }
>
> -int
> -PyThread_acquire_lock(PyThread_type_lock lock, int waitflag)
> +int
> +PyThread_acquire_lock_timed(PyThread_type_lock lock, PY_TIMEOUT_T microseconds)
> {
> int success;
> sem_t *thelock = (sem_t *)lock;
> int status, error = 0;
> + struct timeval tv;
> + struct timespec ts;
>
> - dprintf(("PyThread_acquire_lock(%p, %d) called\n", lock, waitflag));
> + dprintf(("PyThread_acquire_lock_timed(%p, %lld) called\n",
> + lock, microseconds));
>
> + if (microseconds > 0) {
> + GETTIMEOFDAY(&tv);
> + tv.tv_usec += microseconds % 1000000;
> + tv.tv_sec += microseconds / 1000000;
> + tv.tv_sec += tv.tv_usec / 1000000;
> + tv.tv_usec %= 1000000;
> + ts.tv_sec = tv.tv_sec;
> + ts.tv_nsec = tv.tv_usec * 1000;
> + }
> do {
> - if (waitflag)
> + if (microseconds > 0)
> + status = fix_status(sem_timedwait(thelock, &ts));
> + else if (microseconds == 0)
> + status = fix_status(sem_trywait(thelock));
> + else
> status = fix_status(sem_wait(thelock));
> - else
> - status = fix_status(sem_trywait(thelock));
> } while (status == EINTR); /* Retry if interrupted by a signal */
>
> - if (waitflag) {
> + if (microseconds > 0) {
> + if (status != ETIMEDOUT)
> + CHECK_STATUS("sem_timedwait");
> + }
> + else if (microseconds == 0) {
> + if (status != EAGAIN)
> + CHECK_STATUS("sem_trywait");
> + }
> + else {
> CHECK_STATUS("sem_wait");
> - } else if (status != EAGAIN) {
> - CHECK_STATUS("sem_trywait");
> }
>
> success = (status == 0) ? 1 : 0;
>
> - dprintf(("PyThread_acquire_lock(%p, %d) -> %d\n", lock, waitflag, success));
> + dprintf(("PyThread_acquire_lock_timed(%p, %lld) -> %d\n",
> + lock, microseconds, success));
> return success;
> }
>
> +int
> +PyThread_acquire_lock(PyThread_type_lock lock, int waitflag)
> +{
> + return PyThread_acquire_lock_timed(lock, waitflag ? -1 : 0);
> +}
> +
> void
> PyThread_release_lock(PyThread_type_lock lock)
> {
> @@ -430,40 +465,70 @@ PyThread_free_lock(PyThread_type_lock lo
> free((void *)thelock);
> }
>
> -int
> -PyThread_acquire_lock(PyThread_type_lock lock, int waitflag)
> +int
> +PyThread_acquire_lock_timed(PyThread_type_lock lock, PY_TIMEOUT_T microseconds)
> {
> int success;
> pthread_lock *thelock = (pthread_lock *)lock;
> int status, error = 0;
>
> - dprintf(("PyThread_acquire_lock(%p, %d) called\n", lock, waitflag));
> + dprintf(("PyThread_acquire_lock_timed(%p, %lld) called\n",
> + lock, microseconds));
>
> status = pthread_mutex_lock( &thelock->mut );
> CHECK_STATUS("pthread_mutex_lock[1]");
> success = thelock->locked == 0;
>
> - if ( !success && waitflag ) {
> + if (!success && microseconds != 0) {
> + struct timeval tv;
> + struct timespec ts;
> + if (microseconds > 0) {
> + GETTIMEOFDAY(&tv);
> + tv.tv_usec += microseconds % 1000000;
> + tv.tv_sec += microseconds / 1000000;
> + tv.tv_sec += tv.tv_usec / 1000000;
> + tv.tv_usec %= 1000000;
> + ts.tv_sec = tv.tv_sec;
> + ts.tv_nsec = tv.tv_usec * 1000;
Pull this into a helper function so it's not duplicated between the
sem and mutex implementations?
> + }
> /* continue trying until we get the lock */
>
> /* mut must be locked by me -- part of the condition
> * protocol */
> - while ( thelock->locked ) {
> - status = pthread_cond_wait(&thelock->lock_released,
> - &thelock->mut);
> - CHECK_STATUS("pthread_cond_wait");
> + while (thelock->locked) {
> + if (microseconds > 0) {
> + status = pthread_cond_timedwait(
> + &thelock->lock_released,
> + &thelock->mut, &ts);
> + if (status == ETIMEDOUT)
> + break;
> + CHECK_STATUS("pthread_cond_timed_wait");
> + }
> + else {
> + status = pthread_cond_wait(
> + &thelock->lock_released,
> + &thelock->mut);
> + CHECK_STATUS("pthread_cond_wait");
> + }
> }
> - success = 1;
> + success = (status == 0);
> }
> if (success) thelock->locked = 1;
> status = pthread_mutex_unlock( &thelock->mut );
> CHECK_STATUS("pthread_mutex_unlock[1]");
>
> if (error) success = 0;
> - dprintf(("PyThread_acquire_lock(%p, %d) -> %d\n", lock, waitflag, success));
> + dprintf(("PyThread_acquire_lock_timed(%p, %lld) -> %d\n",
> + lock, microseconds, success));
> return success;
> }
>
> +int
> +PyThread_acquire_lock(PyThread_type_lock lock, int waitflag)
> +{
> + return PyThread_acquire_lock_timed(lock, waitflag ? -1 : 0);
> +}
> +
> void
> PyThread_release_lock(PyThread_type_lock lock)
> {
> |
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