cpython/Include/internal/pycore_pythread.h

156 lines
5.2 KiB
C

#ifndef Py_INTERNAL_PYTHREAD_H
#define Py_INTERNAL_PYTHREAD_H
#ifdef __cplusplus
extern "C" {
#endif
#ifndef Py_BUILD_CORE
# error "this header requires Py_BUILD_CORE define"
#endif
#include "dynamic_annotations.h" // _Py_ANNOTATE_PURE_HAPPENS_BEFORE_MUTEX
// Get _POSIX_THREADS and _POSIX_SEMAPHORES macros if available
#if (defined(HAVE_UNISTD_H) && !defined(_POSIX_THREADS) \
&& !defined(_POSIX_SEMAPHORES))
# include <unistd.h> // _POSIX_THREADS, _POSIX_SEMAPHORES
#endif
#if (defined(HAVE_PTHREAD_H) && !defined(_POSIX_THREADS) \
&& !defined(_POSIX_SEMAPHORES))
// This means pthreads are not implemented in libc headers, hence the macro
// not present in <unistd.h>. But they still can be implemented as an
// external library (e.g. gnu pth in pthread emulation)
# include <pthread.h> // _POSIX_THREADS, _POSIX_SEMAPHORES
#endif
#if !defined(_POSIX_THREADS) && defined(__hpux) && defined(_SC_THREADS)
// Check if we're running on HP-UX and _SC_THREADS is defined. If so, then
// enough of the POSIX threads package is implemented to support Python
// threads.
//
// This is valid for HP-UX 11.23 running on an ia64 system. If needed, add
// a check of __ia64 to verify that we're running on an ia64 system instead
// of a pa-risc system.
# define _POSIX_THREADS
#endif
#if defined(_POSIX_THREADS) || defined(HAVE_PTHREAD_STUBS)
# define _USE_PTHREADS
#endif
#if defined(_USE_PTHREADS) && defined(HAVE_PTHREAD_CONDATTR_SETCLOCK) && defined(HAVE_CLOCK_GETTIME) && defined(CLOCK_MONOTONIC)
// monotonic is supported statically. It doesn't mean it works on runtime.
# define CONDATTR_MONOTONIC
#endif
#if defined(HAVE_PTHREAD_STUBS)
#include <stdbool.h> // bool
// pthread_key
struct py_stub_tls_entry {
bool in_use;
void *value;
};
#endif
struct _pythread_runtime_state {
int initialized;
#ifdef _USE_PTHREADS
// This matches when thread_pthread.h is used.
struct {
/* NULL when pthread_condattr_setclock(CLOCK_MONOTONIC) is not supported. */
pthread_condattr_t *ptr;
# ifdef CONDATTR_MONOTONIC
/* The value to which condattr_monotonic is set. */
pthread_condattr_t val;
# endif
} _condattr_monotonic;
#endif // USE_PTHREADS
#if defined(HAVE_PTHREAD_STUBS)
struct {
struct py_stub_tls_entry tls_entries[PTHREAD_KEYS_MAX];
} stubs;
#endif
};
#ifdef HAVE_FORK
/* Private function to reinitialize a lock at fork in the child process.
Reset the lock to the unlocked state.
Return 0 on success, return -1 on error. */
extern int _PyThread_at_fork_reinit(PyThread_type_lock *lock);
#endif /* HAVE_FORK */
// unset: -1 seconds, in nanoseconds
#define PyThread_UNSET_TIMEOUT ((_PyTime_t)(-1 * 1000 * 1000 * 1000))
// Exported for the _xxinterpchannels module.
PyAPI_FUNC(int) PyThread_ParseTimeoutArg(
PyObject *arg,
int blocking,
PY_TIMEOUT_T *timeout);
/* Helper to acquire an interruptible lock with a timeout. If the lock acquire
* is interrupted, signal handlers are run, and if they raise an exception,
* PY_LOCK_INTR is returned. Otherwise, PY_LOCK_ACQUIRED or PY_LOCK_FAILURE
* are returned, depending on whether the lock can be acquired within the
* timeout.
*/
// Exported for the _xxinterpchannels module.
PyAPI_FUNC(PyLockStatus) PyThread_acquire_lock_timed_with_retries(
PyThread_type_lock,
PY_TIMEOUT_T microseconds);
typedef unsigned long long PyThread_ident_t;
typedef Py_uintptr_t PyThread_handle_t;
#define PY_FORMAT_THREAD_IDENT_T "llu"
#define Py_PARSE_THREAD_IDENT_T "K"
PyAPI_FUNC(PyThread_ident_t) PyThread_get_thread_ident_ex(void);
/* Thread joining APIs.
*
* These APIs have a strict contract:
* - Either PyThread_join_thread or PyThread_detach_thread must be called
* exactly once with the given handle.
* - Calling neither PyThread_join_thread nor PyThread_detach_thread results
* in a resource leak until the end of the process.
* - Any other usage, such as calling both PyThread_join_thread and
* PyThread_detach_thread, or calling them more than once (including
* simultaneously), results in undefined behavior.
*/
PyAPI_FUNC(int) PyThread_start_joinable_thread(void (*func)(void *),
void *arg,
PyThread_ident_t* ident,
PyThread_handle_t* handle);
/*
* Join a thread started with `PyThread_start_joinable_thread`.
* This function cannot be interrupted. It returns 0 on success,
* a non-zero value on failure.
*/
PyAPI_FUNC(int) PyThread_join_thread(PyThread_handle_t);
/*
* Detach a thread started with `PyThread_start_joinable_thread`, such
* that its resources are relased as soon as it exits.
* This function cannot be interrupted. It returns 0 on success,
* a non-zero value on failure.
*/
PyAPI_FUNC(int) PyThread_detach_thread(PyThread_handle_t);
/*
* Obtain the new thread ident and handle in a forked child process.
*/
PyAPI_FUNC(void) PyThread_update_thread_after_fork(PyThread_ident_t* ident,
PyThread_handle_t* handle);
#ifdef __cplusplus
}
#endif
#endif /* !Py_INTERNAL_PYTHREAD_H */