jpayne@69: #ifndef Py_CPYTHON_PYSTATE_H
jpayne@69: #  error "this header file must not be included directly"
jpayne@69: #endif
jpayne@69: 
jpayne@69: #ifdef __cplusplus
jpayne@69: extern "C" {
jpayne@69: #endif
jpayne@69: 
jpayne@69: #include "cpython/initconfig.h"
jpayne@69: 
jpayne@69: PyAPI_FUNC(int) _PyInterpreterState_RequiresIDRef(PyInterpreterState *);
jpayne@69: PyAPI_FUNC(void) _PyInterpreterState_RequireIDRef(PyInterpreterState *, int);
jpayne@69: 
jpayne@69: PyAPI_FUNC(PyObject *) _PyInterpreterState_GetMainModule(PyInterpreterState *);
jpayne@69: 
jpayne@69: /* State unique per thread */
jpayne@69: 
jpayne@69: /* Py_tracefunc return -1 when raising an exception, or 0 for success. */
jpayne@69: typedef int (*Py_tracefunc)(PyObject *, struct _frame *, int, PyObject *);
jpayne@69: 
jpayne@69: /* The following values are used for 'what' for tracefunc functions
jpayne@69:  *
jpayne@69:  * To add a new kind of trace event, also update "trace_init" in
jpayne@69:  * Python/sysmodule.c to define the Python level event name
jpayne@69:  */
jpayne@69: #define PyTrace_CALL 0
jpayne@69: #define PyTrace_EXCEPTION 1
jpayne@69: #define PyTrace_LINE 2
jpayne@69: #define PyTrace_RETURN 3
jpayne@69: #define PyTrace_C_CALL 4
jpayne@69: #define PyTrace_C_EXCEPTION 5
jpayne@69: #define PyTrace_C_RETURN 6
jpayne@69: #define PyTrace_OPCODE 7
jpayne@69: 
jpayne@69: 
jpayne@69: typedef struct _err_stackitem {
jpayne@69:     /* This struct represents an entry on the exception stack, which is a
jpayne@69:      * per-coroutine state. (Coroutine in the computer science sense,
jpayne@69:      * including the thread and generators).
jpayne@69:      * This ensures that the exception state is not impacted by "yields"
jpayne@69:      * from an except handler.
jpayne@69:      */
jpayne@69:     PyObject *exc_type, *exc_value, *exc_traceback;
jpayne@69: 
jpayne@69:     struct _err_stackitem *previous_item;
jpayne@69: 
jpayne@69: } _PyErr_StackItem;
jpayne@69: 
jpayne@69: 
jpayne@69: // The PyThreadState typedef is in Include/pystate.h.
jpayne@69: struct _ts {
jpayne@69:     /* See Python/ceval.c for comments explaining most fields */
jpayne@69: 
jpayne@69:     struct _ts *prev;
jpayne@69:     struct _ts *next;
jpayne@69:     PyInterpreterState *interp;
jpayne@69: 
jpayne@69:     struct _frame *frame;
jpayne@69:     int recursion_depth;
jpayne@69:     char overflowed; /* The stack has overflowed. Allow 50 more calls
jpayne@69:                         to handle the runtime error. */
jpayne@69:     char recursion_critical; /* The current calls must not cause
jpayne@69:                                 a stack overflow. */
jpayne@69:     int stackcheck_counter;
jpayne@69: 
jpayne@69:     /* 'tracing' keeps track of the execution depth when tracing/profiling.
jpayne@69:        This is to prevent the actual trace/profile code from being recorded in
jpayne@69:        the trace/profile. */
jpayne@69:     int tracing;
jpayne@69:     int use_tracing;
jpayne@69: 
jpayne@69:     Py_tracefunc c_profilefunc;
jpayne@69:     Py_tracefunc c_tracefunc;
jpayne@69:     PyObject *c_profileobj;
jpayne@69:     PyObject *c_traceobj;
jpayne@69: 
jpayne@69:     /* The exception currently being raised */
jpayne@69:     PyObject *curexc_type;
jpayne@69:     PyObject *curexc_value;
jpayne@69:     PyObject *curexc_traceback;
jpayne@69: 
jpayne@69:     /* The exception currently being handled, if no coroutines/generators
jpayne@69:      * are present. Always last element on the stack referred to be exc_info.
jpayne@69:      */
jpayne@69:     _PyErr_StackItem exc_state;
jpayne@69: 
jpayne@69:     /* Pointer to the top of the stack of the exceptions currently
jpayne@69:      * being handled */
jpayne@69:     _PyErr_StackItem *exc_info;
jpayne@69: 
jpayne@69:     PyObject *dict;  /* Stores per-thread state */
jpayne@69: 
jpayne@69:     int gilstate_counter;
jpayne@69: 
jpayne@69:     PyObject *async_exc; /* Asynchronous exception to raise */
jpayne@69:     unsigned long thread_id; /* Thread id where this tstate was created */
jpayne@69: 
jpayne@69:     int trash_delete_nesting;
jpayne@69:     PyObject *trash_delete_later;
jpayne@69: 
jpayne@69:     /* Called when a thread state is deleted normally, but not when it
jpayne@69:      * is destroyed after fork().
jpayne@69:      * Pain:  to prevent rare but fatal shutdown errors (issue 18808),
jpayne@69:      * Thread.join() must wait for the join'ed thread's tstate to be unlinked
jpayne@69:      * from the tstate chain.  That happens at the end of a thread's life,
jpayne@69:      * in pystate.c.
jpayne@69:      * The obvious way doesn't quite work:  create a lock which the tstate
jpayne@69:      * unlinking code releases, and have Thread.join() wait to acquire that
jpayne@69:      * lock.  The problem is that we _are_ at the end of the thread's life:
jpayne@69:      * if the thread holds the last reference to the lock, decref'ing the
jpayne@69:      * lock will delete the lock, and that may trigger arbitrary Python code
jpayne@69:      * if there's a weakref, with a callback, to the lock.  But by this time
jpayne@69:      * _PyRuntime.gilstate.tstate_current is already NULL, so only the simplest
jpayne@69:      * of C code can be allowed to run (in particular it must not be possible to
jpayne@69:      * release the GIL).
jpayne@69:      * So instead of holding the lock directly, the tstate holds a weakref to
jpayne@69:      * the lock:  that's the value of on_delete_data below.  Decref'ing a
jpayne@69:      * weakref is harmless.
jpayne@69:      * on_delete points to _threadmodule.c's static release_sentinel() function.
jpayne@69:      * After the tstate is unlinked, release_sentinel is called with the
jpayne@69:      * weakref-to-lock (on_delete_data) argument, and release_sentinel releases
jpayne@69:      * the indirectly held lock.
jpayne@69:      */
jpayne@69:     void (*on_delete)(void *);
jpayne@69:     void *on_delete_data;
jpayne@69: 
jpayne@69:     int coroutine_origin_tracking_depth;
jpayne@69: 
jpayne@69:     PyObject *async_gen_firstiter;
jpayne@69:     PyObject *async_gen_finalizer;
jpayne@69: 
jpayne@69:     PyObject *context;
jpayne@69:     uint64_t context_ver;
jpayne@69: 
jpayne@69:     /* Unique thread state id. */
jpayne@69:     uint64_t id;
jpayne@69: 
jpayne@69:     /* XXX signal handlers should also be here */
jpayne@69: 
jpayne@69: };
jpayne@69: 
jpayne@69: /* Get the current interpreter state.
jpayne@69: 
jpayne@69:    Issue a fatal error if there no current Python thread state or no current
jpayne@69:    interpreter. It cannot return NULL.
jpayne@69: 
jpayne@69:    The caller must hold the GIL.*/
jpayne@69: PyAPI_FUNC(PyInterpreterState *) _PyInterpreterState_Get(void);
jpayne@69: 
jpayne@69: PyAPI_FUNC(int) _PyState_AddModule(PyObject*, struct PyModuleDef*);
jpayne@69: PyAPI_FUNC(void) _PyState_ClearModules(void);
jpayne@69: PyAPI_FUNC(PyThreadState *) _PyThreadState_Prealloc(PyInterpreterState *);
jpayne@69: 
jpayne@69: /* Similar to PyThreadState_Get(), but don't issue a fatal error
jpayne@69:  * if it is NULL. */
jpayne@69: PyAPI_FUNC(PyThreadState *) _PyThreadState_UncheckedGet(void);
jpayne@69: 
jpayne@69: /* PyGILState */
jpayne@69: 
jpayne@69: /* Helper/diagnostic function - return 1 if the current thread
jpayne@69:    currently holds the GIL, 0 otherwise.
jpayne@69: 
jpayne@69:    The function returns 1 if _PyGILState_check_enabled is non-zero. */
jpayne@69: PyAPI_FUNC(int) PyGILState_Check(void);
jpayne@69: 
jpayne@69: /* Get the single PyInterpreterState used by this process' GILState
jpayne@69:    implementation.
jpayne@69: 
jpayne@69:    This function doesn't check for error. Return NULL before _PyGILState_Init()
jpayne@69:    is called and after _PyGILState_Fini() is called.
jpayne@69: 
jpayne@69:    See also _PyInterpreterState_Get() and _PyInterpreterState_GET_UNSAFE(). */
jpayne@69: PyAPI_FUNC(PyInterpreterState *) _PyGILState_GetInterpreterStateUnsafe(void);
jpayne@69: 
jpayne@69: /* The implementation of sys._current_frames()  Returns a dict mapping
jpayne@69:    thread id to that thread's current frame.
jpayne@69: */
jpayne@69: PyAPI_FUNC(PyObject *) _PyThread_CurrentFrames(void);
jpayne@69: 
jpayne@69: /* Routines for advanced debuggers, requested by David Beazley.
jpayne@69:    Don't use unless you know what you are doing! */
jpayne@69: PyAPI_FUNC(PyInterpreterState *) PyInterpreterState_Main(void);
jpayne@69: PyAPI_FUNC(PyInterpreterState *) PyInterpreterState_Head(void);
jpayne@69: PyAPI_FUNC(PyInterpreterState *) PyInterpreterState_Next(PyInterpreterState *);
jpayne@69: PyAPI_FUNC(PyThreadState *) PyInterpreterState_ThreadHead(PyInterpreterState *);
jpayne@69: PyAPI_FUNC(PyThreadState *) PyThreadState_Next(PyThreadState *);
jpayne@69: 
jpayne@69: typedef struct _frame *(*PyThreadFrameGetter)(PyThreadState *self_);
jpayne@69: 
jpayne@69: /* cross-interpreter data */
jpayne@69: 
jpayne@69: struct _xid;
jpayne@69: 
jpayne@69: // _PyCrossInterpreterData is similar to Py_buffer as an effectively
jpayne@69: // opaque struct that holds data outside the object machinery.  This
jpayne@69: // is necessary to pass safely between interpreters in the same process.
jpayne@69: typedef struct _xid {
jpayne@69:     // data is the cross-interpreter-safe derivation of a Python object
jpayne@69:     // (see _PyObject_GetCrossInterpreterData).  It will be NULL if the
jpayne@69:     // new_object func (below) encodes the data.
jpayne@69:     void *data;
jpayne@69:     // obj is the Python object from which the data was derived.  This
jpayne@69:     // is non-NULL only if the data remains bound to the object in some
jpayne@69:     // way, such that the object must be "released" (via a decref) when
jpayne@69:     // the data is released.  In that case the code that sets the field,
jpayne@69:     // likely a registered "crossinterpdatafunc", is responsible for
jpayne@69:     // ensuring it owns the reference (i.e. incref).
jpayne@69:     PyObject *obj;
jpayne@69:     // interp is the ID of the owning interpreter of the original
jpayne@69:     // object.  It corresponds to the active interpreter when
jpayne@69:     // _PyObject_GetCrossInterpreterData() was called.  This should only
jpayne@69:     // be set by the cross-interpreter machinery.
jpayne@69:     //
jpayne@69:     // We use the ID rather than the PyInterpreterState to avoid issues
jpayne@69:     // with deleted interpreters.  Note that IDs are never re-used, so
jpayne@69:     // each one will always correspond to a specific interpreter
jpayne@69:     // (whether still alive or not).
jpayne@69:     int64_t interp;
jpayne@69:     // new_object is a function that returns a new object in the current
jpayne@69:     // interpreter given the data.  The resulting object (a new
jpayne@69:     // reference) will be equivalent to the original object.  This field
jpayne@69:     // is required.
jpayne@69:     PyObject *(*new_object)(struct _xid *);
jpayne@69:     // free is called when the data is released.  If it is NULL then
jpayne@69:     // nothing will be done to free the data.  For some types this is
jpayne@69:     // okay (e.g. bytes) and for those types this field should be set
jpayne@69:     // to NULL.  However, for most the data was allocated just for
jpayne@69:     // cross-interpreter use, so it must be freed when
jpayne@69:     // _PyCrossInterpreterData_Release is called or the memory will
jpayne@69:     // leak.  In that case, at the very least this field should be set
jpayne@69:     // to PyMem_RawFree (the default if not explicitly set to NULL).
jpayne@69:     // The call will happen with the original interpreter activated.
jpayne@69:     void (*free)(void *);
jpayne@69: } _PyCrossInterpreterData;
jpayne@69: 
jpayne@69: PyAPI_FUNC(int) _PyObject_GetCrossInterpreterData(PyObject *, _PyCrossInterpreterData *);
jpayne@69: PyAPI_FUNC(PyObject *) _PyCrossInterpreterData_NewObject(_PyCrossInterpreterData *);
jpayne@69: PyAPI_FUNC(void) _PyCrossInterpreterData_Release(_PyCrossInterpreterData *);
jpayne@69: 
jpayne@69: PyAPI_FUNC(int) _PyObject_CheckCrossInterpreterData(PyObject *);
jpayne@69: 
jpayne@69: /* cross-interpreter data registry */
jpayne@69: 
jpayne@69: typedef int (*crossinterpdatafunc)(PyObject *, struct _xid *);
jpayne@69: 
jpayne@69: PyAPI_FUNC(int) _PyCrossInterpreterData_RegisterClass(PyTypeObject *, crossinterpdatafunc);
jpayne@69: PyAPI_FUNC(crossinterpdatafunc) _PyCrossInterpreterData_Lookup(PyObject *);
jpayne@69: 
jpayne@69: #ifdef __cplusplus
jpayne@69: }
jpayne@69: #endif