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/* Thread and interpreter state structures and their interfaces */
#ifndef Py_PYSTATE_H
#define Py_PYSTATE_H
#ifdef __cplusplus
extern "C" {
#include "pythread.h"
#include "coreconfig.h"
/* This limitation is for performance and simplicity. If needed it can be
removed (with effort). */
#define MAX_CO_EXTRA_USERS 255
/* State shared between threads */
struct _ts; /* Forward */
struct _is; /* Forward */
struct _frame; /* Forward declaration for PyFrameObject. */
typedef struct _is PyInterpreterState;
typedef PyObject* (*_PyFrameEvalFunction)(struct _frame *, int);
/* Placeholders while working on the new configuration API
* See PEP 432 for final anticipated contents
typedef struct {
int install_signal_handlers; /* Install signal handlers? -1 means unset */
PyObject *argv; /* sys.argv list, can be NULL */
PyObject *executable; /* sys.executable str */
PyObject *prefix; /* sys.prefix str */
PyObject *base_prefix; /* sys.base_prefix str, can be NULL */
PyObject *exec_prefix; /* sys.exec_prefix str */
PyObject *base_exec_prefix; /* sys.base_exec_prefix str, can be NULL */
PyObject *warnoptions; /* sys.warnoptions list, can be NULL */
PyObject *xoptions; /* sys._xoptions dict, can be NULL */
PyObject *module_search_path; /* sys.path list */
PyObject *pycache_prefix; /* sys.pycache_prefix str, can be NULL */
} _PyMainInterpreterConfig;
#define _PyMainInterpreterConfig_INIT \
(_PyMainInterpreterConfig){.install_signal_handlers = -1}
/* Note: _PyMainInterpreterConfig_INIT sets other fields to 0/NULL */
typedef struct _is {
struct _is *next;
struct _ts *tstate_head;
int64_t id;
int64_t id_refcount;
PyThread_type_lock id_mutex;
PyObject *modules;
PyObject *modules_by_index;
PyObject *sysdict;
PyObject *builtins;
PyObject *importlib;
/* Used in Python/sysmodule.c. */
int check_interval;
/* Used in Modules/_threadmodule.c. */
long num_threads;
/* Support for runtime thread stack size tuning.
A value of 0 means using the platform's default stack size
or the size specified by the THREAD_STACK_SIZE macro. */
/* Used in Python/thread.c. */
size_t pythread_stacksize;
PyObject *codec_search_path;
PyObject *codec_search_cache;
PyObject *codec_error_registry;
int codecs_initialized;
int fscodec_initialized;
_PyCoreConfig core_config;
_PyMainInterpreterConfig config;
int dlopenflags;
PyObject *builtins_copy;
PyObject *import_func;
/* Initialized to PyEval_EvalFrameDefault(). */
_PyFrameEvalFunction eval_frame;
Py_ssize_t co_extra_user_count;
freefunc co_extra_freefuncs[MAX_CO_EXTRA_USERS];
#ifdef HAVE_FORK
PyObject *before_forkers;
PyObject *after_forkers_parent;
PyObject *after_forkers_child;
/* AtExit module */
void (*pyexitfunc)(PyObject *);
PyObject *pyexitmodule;
uint64_t tstate_next_unique_id;
} PyInterpreterState;
#endif /* !Py_LIMITED_API */
/* State unique per thread */
#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
* To add a new kind of trace event, also update "trace_init" in
* Python/sysmodule.c to define the Python level event name
#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
#define PyTrace_OPCODE 7
#endif /* Py_LIMITED_API */
typedef struct _ts PyThreadState;
typedef struct _err_stackitem {
/* This struct represents an entry on the exception stack, which is a
* per-coroutine state. (Coroutine in the computer science sense,
* including the thread and generators).
* This ensures that the exception state is not impacted by "yields"
* from an except handler.
PyObject *exc_type, *exc_value, *exc_traceback;
struct _err_stackitem *previous_item;
} _PyErr_StackItem;
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. */
int stackcheck_counter;
/* '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;
/* The exception currently being raised */
PyObject *curexc_type;
PyObject *curexc_value;
PyObject *curexc_traceback;
/* The exception currently being handled, if no coroutines/generators
* are present. Always last element on the stack referred to be exc_info.
_PyErr_StackItem exc_state;
/* Pointer to the top of the stack of the exceptions currently
* being handled */
_PyErr_StackItem *exc_info;
PyObject *dict; /* Stores per-thread state */
int gilstate_counter;
PyObject *async_exc; /* Asynchronous exception to raise */
unsigned 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;
int coroutine_origin_tracking_depth;
PyObject *coroutine_wrapper;
int in_coroutine_wrapper;
PyObject *async_gen_firstiter;
PyObject *async_gen_finalizer;
PyObject *context;
uint64_t context_ver;
/* Unique thread state id. */
uint64_t id;
/* XXX signal handlers should also be here */
} PyThreadState;
#endif /* !Py_LIMITED_API */
PyAPI_FUNC(PyInterpreterState *) PyInterpreterState_New(void);
PyAPI_FUNC(void) PyInterpreterState_Clear(PyInterpreterState *);
PyAPI_FUNC(void) PyInterpreterState_Delete(PyInterpreterState *);
#if !defined(Py_LIMITED_API)
PyAPI_FUNC(PyInterpreterState *) _PyInterpreterState_Get(void);
#ifdef Py_BUILD_CORE
/* Macro which should only be used for performance critical code.
Need "#include "internal/pystate.h". See also _PyInterpreterState_Get()
and _PyGILState_GetInterpreterStateUnsafe(). */
# define _PyInterpreterState_GET_UNSAFE() (PyThreadState_GET()->interp)
#if !defined(Py_LIMITED_API) || Py_LIMITED_API+0 >= 0x03070000
/* New in 3.7 */
PyAPI_FUNC(int64_t) PyInterpreterState_GetID(PyInterpreterState *);
#ifndef Py_LIMITED_API
PyAPI_FUNC(int) _PyState_AddModule(PyObject*, struct PyModuleDef*);
#endif /* !Py_LIMITED_API */
#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*);
PyAPI_FUNC(PyObject*) PyState_FindModule(struct PyModuleDef*);
#ifndef Py_LIMITED_API
PyAPI_FUNC(void) _PyState_ClearModules(void);
PyAPI_FUNC(PyThreadState *) PyThreadState_New(PyInterpreterState *);
#ifndef Py_LIMITED_API
PyAPI_FUNC(PyThreadState *) _PyThreadState_Prealloc(PyInterpreterState *);
PyAPI_FUNC(void) _PyThreadState_Init(PyThreadState *);
#endif /* !Py_LIMITED_API */
PyAPI_FUNC(void) PyThreadState_Clear(PyThreadState *);
PyAPI_FUNC(void) PyThreadState_Delete(PyThreadState *);
#ifndef Py_LIMITED_API
PyAPI_FUNC(void) _PyThreadState_DeleteExcept(PyThreadState *tstate);
#endif /* !Py_LIMITED_API */
PyAPI_FUNC(void) PyThreadState_DeleteCurrent(void);
#ifndef Py_LIMITED_API
PyAPI_FUNC(void) _PyGILState_Reinit(void);
#endif /* !Py_LIMITED_API */
/* 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);
#ifndef Py_LIMITED_API
/* Similar to PyThreadState_Get(), but don't issue a fatal error
* if it is NULL. */
PyAPI_FUNC(PyThreadState *) _PyThreadState_UncheckedGet(void);
#endif /* !Py_LIMITED_API */
PyAPI_FUNC(PyThreadState *) PyThreadState_Swap(PyThreadState *);
PyAPI_FUNC(PyObject *) PyThreadState_GetDict(void);
PyAPI_FUNC(int) PyThreadState_SetAsyncExc(unsigned 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
# define _PyThreadState_Current _PyRuntime.gilstate.tstate_current
# define PyThreadState_GET() \
# define PyThreadState_GET() PyThreadState_Get()
/* 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
/* 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.
See also _PyInterpreterState_Get() and _PyInterpreterState_GET_UNSAFE(). */
PyAPI_FUNC(PyInterpreterState *) _PyGILState_GetInterpreterStateUnsafe(void);
#endif /* !Py_LIMITED_API */
/* 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);
/* 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_Main(void);
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_);
#ifdef __cplusplus
#endif /* !Py_PYSTATE_H */