static PyObject *
semlock_iszero(SemLockObject *self)
{
#ifdef HAVE_BROKEN_SEM_GETVALUE
if (sem_trywait(self->handle) < 0) {
if (errno == EAGAIN)
Py_RETURN_TRUE;
return mp_SetError(NULL, MP_STANDARD_ERROR);
} else {
if (sem_post(self->handle) < 0)
return mp_SetError(NULL, MP_STANDARD_ERROR);
Py_RETURN_FALSE;
}
#else
int sval;
if (SEM_GETVALUE(self->handle, &sval) < 0)
return mp_SetError(NULL, MP_STANDARD_ERROR);
return PyBool_FromLong((long)sval == 0);
#endif
}
static PyObject *
semlock_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
{
char buffer[256];
SEM_HANDLE handle = SEM_FAILED;
int kind, maxvalue, value;
PyObject *result;
static char *kwlist[] = {"kind", "value", "maxvalue", NULL};
int try = 0;
if (!PyArg_ParseTupleAndKeywords(args, kwds, "iii", kwlist,
&kind, &value, &maxvalue))
return NULL;
if (kind != RECURSIVE_MUTEX && kind != SEMAPHORE) {
PyErr_SetString(PyExc_ValueError, "unrecognized kind");
return NULL;
}
/* Create a semaphore with a unique name. The bytes returned by
* _PyOS_URandom() are treated as unsigned long to ensure that the filename
* is valid (no special characters). */
do {
unsigned long suffix;
_PyOS_URandom((char *)&suffix, sizeof(suffix));
PyOS_snprintf(buffer, sizeof(buffer), "/mp%ld-%lu", (long)getpid(),
suffix);
SEM_CLEAR_ERROR();
handle = SEM_CREATE(buffer, value, maxvalue);
} while ((handle == SEM_FAILED) && (errno == EEXIST) && (++try < 100));
/* On Windows we should fail if GetLastError()==ERROR_ALREADY_EXISTS */
if (handle == SEM_FAILED || SEM_GET_LAST_ERROR() != 0)
goto failure;
if (SEM_UNLINK(buffer) < 0)
goto failure;
result = newsemlockobject(type, handle, kind, maxvalue);
if (!result)
goto failure;
return result;
failure:
if (handle != SEM_FAILED)
SEM_CLOSE(handle);
mp_SetError(NULL, MP_STANDARD_ERROR);
return NULL;
}
static PyObject *
semlock_getvalue(SemLockObject *self)
{
#ifdef HAVE_BROKEN_SEM_GETVALUE
PyErr_SetNone(PyExc_NotImplementedError);
return NULL;
#else
int sval;
if (SEM_GETVALUE(self->handle, &sval) < 0)
return mp_SetError(NULL, MP_STANDARD_ERROR);
/* some posix implementations use negative numbers to indicate
the number of waiting threads */
if (sval < 0)
sval = 0;
return PyInt_FromLong((long)sval);
#endif
}
static PyObject *
semlock_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
{
char buffer[256];
SEM_HANDLE handle = SEM_FAILED;
int kind, maxvalue, value;
PyObject *result;
static char *kwlist[] = {"kind", "value", "maxvalue", NULL};
static int counter = 0;
if (!PyArg_ParseTupleAndKeywords(args, kwds, "iii", kwlist,
&kind, &value, &maxvalue))
return NULL;
if (kind != RECURSIVE_MUTEX && kind != SEMAPHORE) {
PyErr_SetString(PyExc_ValueError, "unrecognized kind");
return NULL;
}
PyOS_snprintf(buffer, sizeof(buffer), "/mp%ld-%d", (long)getpid(), counter++);
SEM_CLEAR_ERROR();
handle = SEM_CREATE(buffer, value, maxvalue);
/* On Windows we should fail if GetLastError()==ERROR_ALREADY_EXISTS */
if (handle == SEM_FAILED || SEM_GET_LAST_ERROR() != 0)
goto failure;
if (SEM_UNLINK(buffer) < 0)
goto failure;
result = newsemlockobject(type, handle, kind, maxvalue);
if (!result)
goto failure;
return result;
failure:
if (handle != SEM_FAILED)
SEM_CLOSE(handle);
mp_SetError(NULL, MP_STANDARD_ERROR);
return NULL;
}
