cpython/Include/pystate.h

293 lines
9.8 KiB
C

/* Thread and interpreter state structures and their interfaces */
#ifndef Py_PYSTATE_H
#define Py_PYSTATE_H
#ifdef __cplusplus
extern "C" {
#endif
/* State shared between threads */
struct _ts; /* Forward */
struct _is; /* Forward */
#ifdef Py_LIMITED_API
typedef struct _is PyInterpreterState;
#else
typedef struct _is {
struct _is *next;
struct _ts *tstate_head;
PyObject *modules;
PyObject *modules_by_index;
PyObject *sysdict;
PyObject *builtins;
PyObject *importlib;
PyObject *codec_search_path;
PyObject *codec_search_cache;
PyObject *codec_error_registry;
int codecs_initialized;
int fscodec_initialized;
#ifdef HAVE_DLOPEN
int dlopenflags;
#endif
#ifdef WITH_TSC
int tscdump;
#endif
PyObject *builtins_copy;
PyObject *import_func;
} PyInterpreterState;
#endif
/* State unique per thread */
struct _frame; /* Avoid including frameobject.h */
#ifndef Py_LIMITED_API
/* Py_tracefunc return -1 when raising an exception, or 0 for success. */
typedef int (*Py_tracefunc)(PyObject *, struct _frame *, int, PyObject *);
/* The following values are used for 'what' for tracefunc functions: */
#define PyTrace_CALL 0
#define PyTrace_EXCEPTION 1
#define PyTrace_LINE 2
#define PyTrace_RETURN 3
#define PyTrace_C_CALL 4
#define PyTrace_C_EXCEPTION 5
#define PyTrace_C_RETURN 6
#endif
#ifdef Py_LIMITED_API
typedef struct _ts PyThreadState;
#else
typedef struct _ts {
/* See Python/ceval.c for comments explaining most fields */
struct _ts *prev;
struct _ts *next;
PyInterpreterState *interp;
struct _frame *frame;
int recursion_depth;
char overflowed; /* The stack has overflowed. Allow 50 more calls
to handle the runtime error. */
char recursion_critical; /* The current calls must not cause
a stack overflow. */
/* 'tracing' keeps track of the execution depth when tracing/profiling.
This is to prevent the actual trace/profile code from being recorded in
the trace/profile. */
int tracing;
int use_tracing;
Py_tracefunc c_profilefunc;
Py_tracefunc c_tracefunc;
PyObject *c_profileobj;
PyObject *c_traceobj;
PyObject *curexc_type;
PyObject *curexc_value;
PyObject *curexc_traceback;
PyObject *exc_type;
PyObject *exc_value;
PyObject *exc_traceback;
PyObject *dict; /* Stores per-thread state */
int gilstate_counter;
PyObject *async_exc; /* Asynchronous exception to raise */
long thread_id; /* Thread id where this tstate was created */
int trash_delete_nesting;
PyObject *trash_delete_later;
/* Called when a thread state is deleted normally, but not when it
* is destroyed after fork().
* Pain: to prevent rare but fatal shutdown errors (issue 18808),
* Thread.join() must wait for the join'ed thread's tstate to be unlinked
* from the tstate chain. That happens at the end of a thread's life,
* in pystate.c.
* The obvious way doesn't quite work: create a lock which the tstate
* unlinking code releases, and have Thread.join() wait to acquire that
* lock. The problem is that we _are_ at the end of the thread's life:
* if the thread holds the last reference to the lock, decref'ing the
* lock will delete the lock, and that may trigger arbitrary Python code
* if there's a weakref, with a callback, to the lock. But by this time
* _PyThreadState_Current is already NULL, so only the simplest of C code
* can be allowed to run (in particular it must not be possible to
* release the GIL).
* So instead of holding the lock directly, the tstate holds a weakref to
* the lock: that's the value of on_delete_data below. Decref'ing a
* weakref is harmless.
* on_delete points to _threadmodule.c's static release_sentinel() function.
* After the tstate is unlinked, release_sentinel is called with the
* weakref-to-lock (on_delete_data) argument, and release_sentinel releases
* the indirectly held lock.
*/
void (*on_delete)(void *);
void *on_delete_data;
PyObject *coroutine_wrapper;
int in_coroutine_wrapper;
/* XXX signal handlers should also be here */
} PyThreadState;
#endif
PyAPI_FUNC(PyInterpreterState *) PyInterpreterState_New(void);
PyAPI_FUNC(void) PyInterpreterState_Clear(PyInterpreterState *);
PyAPI_FUNC(void) PyInterpreterState_Delete(PyInterpreterState *);
PyAPI_FUNC(int) _PyState_AddModule(PyObject*, struct PyModuleDef*);
#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x03030000
/* New in 3.3 */
PyAPI_FUNC(int) PyState_AddModule(PyObject*, struct PyModuleDef*);
PyAPI_FUNC(int) PyState_RemoveModule(struct PyModuleDef*);
#endif
PyAPI_FUNC(PyObject*) PyState_FindModule(struct PyModuleDef*);
#ifndef Py_LIMITED_API
PyAPI_FUNC(void) _PyState_ClearModules(void);
#endif
PyAPI_FUNC(PyThreadState *) PyThreadState_New(PyInterpreterState *);
PyAPI_FUNC(PyThreadState *) _PyThreadState_Prealloc(PyInterpreterState *);
PyAPI_FUNC(void) _PyThreadState_Init(PyThreadState *);
PyAPI_FUNC(void) PyThreadState_Clear(PyThreadState *);
PyAPI_FUNC(void) PyThreadState_Delete(PyThreadState *);
PyAPI_FUNC(void) _PyThreadState_DeleteExcept(PyThreadState *tstate);
#ifdef WITH_THREAD
PyAPI_FUNC(void) PyThreadState_DeleteCurrent(void);
PyAPI_FUNC(void) _PyGILState_Reinit(void);
#endif
/* Return the current thread state. The global interpreter lock must be held.
* When the current thread state is NULL, this issues a fatal error (so that
* the caller needn't check for NULL). */
PyAPI_FUNC(PyThreadState *) PyThreadState_Get(void);
/* Similar to PyThreadState_Get(), but don't issue a fatal error
* if it is NULL. */
PyAPI_FUNC(PyThreadState *) _PyThreadState_UncheckedGet(void);
PyAPI_FUNC(PyThreadState *) PyThreadState_Swap(PyThreadState *);
PyAPI_FUNC(PyObject *) PyThreadState_GetDict(void);
PyAPI_FUNC(int) PyThreadState_SetAsyncExc(long, PyObject *);
/* Variable and macro for in-line access to current thread state */
/* Assuming the current thread holds the GIL, this is the
PyThreadState for the current thread. */
#ifdef Py_BUILD_CORE
PyAPI_DATA(_Py_atomic_address) _PyThreadState_Current;
# define PyThreadState_GET() \
((PyThreadState*)_Py_atomic_load_relaxed(&_PyThreadState_Current))
#else
# define PyThreadState_GET() PyThreadState_Get()
#endif
typedef
enum {PyGILState_LOCKED, PyGILState_UNLOCKED}
PyGILState_STATE;
#ifdef WITH_THREAD
/* Ensure that the current thread is ready to call the Python
C API, regardless of the current state of Python, or of its
thread lock. This may be called as many times as desired
by a thread so long as each call is matched with a call to
PyGILState_Release(). In general, other thread-state APIs may
be used between _Ensure() and _Release() calls, so long as the
thread-state is restored to its previous state before the Release().
For example, normal use of the Py_BEGIN_ALLOW_THREADS/
Py_END_ALLOW_THREADS macros are acceptable.
The return value is an opaque "handle" to the thread state when
PyGILState_Ensure() was called, and must be passed to
PyGILState_Release() to ensure Python is left in the same state. Even
though recursive calls are allowed, these handles can *not* be shared -
each unique call to PyGILState_Ensure must save the handle for its
call to PyGILState_Release.
When the function returns, the current thread will hold the GIL.
Failure is a fatal error.
*/
PyAPI_FUNC(PyGILState_STATE) PyGILState_Ensure(void);
/* Release any resources previously acquired. After this call, Python's
state will be the same as it was prior to the corresponding
PyGILState_Ensure() call (but generally this state will be unknown to
the caller, hence the use of the GILState API.)
Every call to PyGILState_Ensure must be matched by a call to
PyGILState_Release on the same thread.
*/
PyAPI_FUNC(void) PyGILState_Release(PyGILState_STATE);
/* Helper/diagnostic function - get the current thread state for
this thread. May return NULL if no GILState API has been used
on the current thread. Note that the main thread always has such a
thread-state, even if no auto-thread-state call has been made
on the main thread.
*/
PyAPI_FUNC(PyThreadState *) PyGILState_GetThisThreadState(void);
#ifndef Py_LIMITED_API
/* Issue #26558: Flag to disable PyGILState_Check().
If set to non-zero, PyGILState_Check() always return 1. */
PyAPI_DATA(int) _PyGILState_check_enabled;
/* Helper/diagnostic function - return 1 if the current thread
currently holds the GIL, 0 otherwise.
The function returns 1 if _PyGILState_check_enabled is non-zero. */
PyAPI_FUNC(int) PyGILState_Check(void);
/* Unsafe function to get the single PyInterpreterState used by this process'
GILState implementation.
Return NULL before _PyGILState_Init() is called and after _PyGILState_Fini()
is called. */
PyAPI_FUNC(PyInterpreterState *) _PyGILState_GetInterpreterStateUnsafe(void);
#endif
#endif /* #ifdef WITH_THREAD */
/* The implementation of sys._current_frames() Returns a dict mapping
thread id to that thread's current frame.
*/
#ifndef Py_LIMITED_API
PyAPI_FUNC(PyObject *) _PyThread_CurrentFrames(void);
#endif
/* Routines for advanced debuggers, requested by David Beazley.
Don't use unless you know what you are doing! */
#ifndef Py_LIMITED_API
PyAPI_FUNC(PyInterpreterState *) PyInterpreterState_Head(void);
PyAPI_FUNC(PyInterpreterState *) PyInterpreterState_Next(PyInterpreterState *);
PyAPI_FUNC(PyThreadState *) PyInterpreterState_ThreadHead(PyInterpreterState *);
PyAPI_FUNC(PyThreadState *) PyThreadState_Next(PyThreadState *);
typedef struct _frame *(*PyThreadFrameGetter)(PyThreadState *self_);
#endif
/* hook for PyEval_GetFrame(), requested for Psyco */
#ifndef Py_LIMITED_API
PyAPI_DATA(PyThreadFrameGetter) _PyThreadState_GetFrame;
#endif
#ifdef __cplusplus
}
#endif
#endif /* !Py_PYSTATE_H */