diff options
Diffstat (limited to 'Include/pythread.h')
| -rw-r--r-- | Include/pythread.h | 50 |
1 files changed, 50 insertions, 0 deletions
diff --git a/Include/pythread.h b/Include/pythread.h index dfd6157..9806c61 100644 --- a/Include/pythread.h +++ b/Include/pythread.h @@ -9,6 +9,14 @@ typedef void *PyThread_type_sema; extern "C" { #endif +/* Return status codes for Python lock acquisition. Chosen for maximum + * backwards compatibility, ie failure -> 0, success -> 1. */ +typedef enum PyLockStatus { + PY_LOCK_FAILURE = 0, + PY_LOCK_ACQUIRED = 1, + PY_LOCK_INTR +} PyLockStatus; + PyAPI_FUNC(void) PyThread_init_thread(void); PyAPI_FUNC(long) PyThread_start_new_thread(void (*)(void *), void *); PyAPI_FUNC(void) PyThread_exit_thread(void); @@ -19,6 +27,48 @@ PyAPI_FUNC(void) PyThread_free_lock(PyThread_type_lock); PyAPI_FUNC(int) PyThread_acquire_lock(PyThread_type_lock, int); #define WAIT_LOCK 1 #define NOWAIT_LOCK 0 + +/* PY_TIMEOUT_T is the integral type used to specify timeouts when waiting + on a lock (see PyThread_acquire_lock_timed() below). + PY_TIMEOUT_MAX is the highest usable value (in microseconds) of that + type, and depends on the system threading API. + + NOTE: this isn't the same value as `_thread.TIMEOUT_MAX`. The _thread + module exposes a higher-level API, with timeouts expressed in seconds + and floating-point numbers allowed. +*/ +#if defined(HAVE_LONG_LONG) +#define PY_TIMEOUT_T PY_LONG_LONG +#define PY_TIMEOUT_MAX PY_LLONG_MAX +#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) +#if (Py_LL(0xFFFFFFFF) * 1000 < PY_TIMEOUT_MAX) +#undef PY_TIMEOUT_MAX +#define PY_TIMEOUT_MAX (Py_LL(0xFFFFFFFF) * 1000) +#endif +#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. + + If intr_flag is true and the acquire is interrupted by a signal, then the + call will return PY_LOCK_INTR. The caller may reattempt to acquire the + lock. +*/ +PyAPI_FUNC(PyLockStatus) PyThread_acquire_lock_timed(PyThread_type_lock, + PY_TIMEOUT_T microseconds, + int intr_flag); + PyAPI_FUNC(void) PyThread_release_lock(PyThread_type_lock); PyAPI_FUNC(size_t) PyThread_get_stacksize(void); |