cpython/Include/pythread.h

#ifndef Py_PYTHREAD_H
#define Py_PYTHREAD_H

PyThread_type_lock;

#ifdef __cplusplus
extern "C" {
#endif

/* Return status codes for Python lock acquisition.  Chosen for maximum
 * backwards compatibility, ie failure -> 0, success -> 1.  */
PyLockStatus;

PyAPI_FUNC(void) PyThread_init_thread(void);
PyAPI_FUNC(unsigned long) PyThread_start_new_thread(void (*)(void *), void *);
/* Terminates the current thread. Considered unsafe.
 *
 * WARNING: This function is only safe to call if all functions in the full call
 * stack are written to safely allow it.  Additionally, the behavior is
 * platform-dependent.  This function should be avoided, and is no longer called
 * by Python itself.  It is retained only for compatibility with existing C
 * extension code.
 *
 * With pthreads, calls `pthread_exit` causes some libcs (glibc?) to attempt to
 * unwind the stack and call C++ destructors; if a `noexcept` function is
 * reached, they may terminate the process. Others (macOS) do unwinding.
 *
 * On Windows, calls `_endthreadex` which kills the thread without calling C++
 * destructors.
 *
 * In either case there is a risk of invalid references remaining to data on the
 * thread stack.
 */
Py_DEPRECATED(3.14) PyAPI_FUNC(void) _Py_NO_RETURN PyThread_exit_thread(void);

PyAPI_FUNC(unsigned long) PyThread_get_thread_ident(void);

#if (defined(__APPLE__) || defined(__linux__) || defined(_WIN32) \
     || defined(__FreeBSD__) || defined(__FreeBSD_kernel__) \
     || defined(__OpenBSD__) || defined(__NetBSD__) \
     || defined(__DragonFly__) || defined(_AIX))
#define PY_HAVE_THREAD_NATIVE_ID
PyAPI_FUNC(unsigned long) PyThread_get_thread_native_id(void);
#endif

PyAPI_FUNC(PyThread_type_lock) PyThread_allocate_lock(void);
PyAPI_FUNC(void) PyThread_free_lock(PyThread_type_lock);
PyAPI_FUNC(int) PyThread_acquire_lock(PyThread_type_lock, int);
#define WAIT_LOCK …
#define NOWAIT_LOCK …

// PY_TIMEOUT_T is the integral type used to specify timeouts when waiting
// on a lock (see PyThread_acquire_lock_timed() below).
#define PY_TIMEOUT_T …


/* 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)

   If *microseconds* is greater than PY_TIMEOUT_MAX, clamp the timeout to
   PY_TIMEOUT_MAX microseconds.

   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);
PyAPI_FUNC(int) PyThread_set_stacksize(size_t);

#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x03030000
PyAPI_FUNC(PyObject*) PyThread_GetInfo(void);
#endif


/* Thread Local Storage (TLS) API
   TLS API is DEPRECATED.  Use Thread Specific Storage (TSS) API.

   The existing TLS API has used int to represent TLS keys across all
   platforms, but it is not POSIX-compliant.  Therefore, the new TSS API uses
   opaque data type to represent TSS keys to be compatible (see PEP 539).
*/
Py_DEPRECATED(3.7) PyAPI_FUNC(int) PyThread_create_key(void);
Py_DEPRECATED(3.7) PyAPI_FUNC(void) PyThread_delete_key(int key);
Py_DEPRECATED(3.7) PyAPI_FUNC(int) PyThread_set_key_value(int key,
                                                          void *value);
Py_DEPRECATED(3.7) PyAPI_FUNC(void *) PyThread_get_key_value(int key);
Py_DEPRECATED(3.7) PyAPI_FUNC(void) PyThread_delete_key_value(int key);

/* Cleanup after a fork */
Py_DEPRECATED(3.7) PyAPI_FUNC(void) PyThread_ReInitTLS(void);


#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x03070000
/* New in 3.7 */
/* Thread Specific Storage (TSS) API */

Py_tss_t;  /* opaque */

PyAPI_FUNC(Py_tss_t *) PyThread_tss_alloc(void);
PyAPI_FUNC(void) PyThread_tss_free(Py_tss_t *key);

/* The parameter key must not be NULL. */
PyAPI_FUNC(int) PyThread_tss_is_created(Py_tss_t *key);
PyAPI_FUNC(int) PyThread_tss_create(Py_tss_t *key);
PyAPI_FUNC(void) PyThread_tss_delete(Py_tss_t *key);
PyAPI_FUNC(int) PyThread_tss_set(Py_tss_t *key, void *value);
PyAPI_FUNC(void *) PyThread_tss_get(Py_tss_t *key);
#endif  /* New in 3.7 */

#ifndef Py_LIMITED_API
#define Py_CPYTHON_PYTHREAD_H
#  include "cpython/pythread.h"
#  undef Py_CPYTHON_PYTHREAD_H
#endif

#ifdef __cplusplus
}
#endif
#endif /* !Py_PYTHREAD_H */