/* -*- indent-tabs-mode: nil; tab-width: 4; -*- */

/* Greenlet object interface */

#ifndef Py_GREENLETOBJECT_H
#define Py_GREENLETOBJECT_H

#include <Python.h>

#ifdef __cplusplus
extern "C" {
#endif

/* This is deprecated and undocumented. It does not change. */
#define GREENLET_VERSION "1.0.0"

typedef struct _greenlet {
    PyObject_HEAD
    char* stack_start;
    char* stack_stop;
    char* stack_copy;
    intptr_t stack_saved;
    struct _greenlet* stack_prev;
    struct _greenlet* parent;
    PyObject* run_info;
    struct _frame* top_frame;
    int recursion_depth;
    PyObject* weakreflist;
#if PY_VERSION_HEX >= 0x030700A3
    _PyErr_StackItem* exc_info;
    _PyErr_StackItem exc_state;
#else
    PyObject* exc_type;
    PyObject* exc_value;
    PyObject* exc_traceback;
#endif
    PyObject* dict;
#if PY_VERSION_HEX >= 0x030700A3
    PyObject* context;
#endif
} PyGreenlet;

#define PyGreenlet_Check(op) PyObject_TypeCheck(op, &PyGreenlet_Type)
#define PyGreenlet_MAIN(op) (((PyGreenlet*)(op))->stack_stop == (char*)-1)
#define PyGreenlet_STARTED(op) (((PyGreenlet*)(op))->stack_stop != NULL)
#define PyGreenlet_ACTIVE(op) (((PyGreenlet*)(op))->stack_start != NULL)
#define PyGreenlet_GET_PARENT(op) (((PyGreenlet*)(op))->parent)

/* C API functions */

/* Total number of symbols that are exported */
#define PyGreenlet_API_pointers 8

#define PyGreenlet_Type_NUM 0
#define PyExc_GreenletError_NUM 1
#define PyExc_GreenletExit_NUM 2

#define PyGreenlet_New_NUM 3
#define PyGreenlet_GetCurrent_NUM 4
#define PyGreenlet_Throw_NUM 5
#define PyGreenlet_Switch_NUM 6
#define PyGreenlet_SetParent_NUM 7

#ifndef GREENLET_MODULE
/* This section is used by modules that uses the greenlet C API */
static void** _PyGreenlet_API = NULL;

#    define PyGreenlet_Type \
        (*(PyTypeObject*)_PyGreenlet_API[PyGreenlet_Type_NUM])

#    define PyExc_GreenletError \
        ((PyObject*)_PyGreenlet_API[PyExc_GreenletError_NUM])

#    define PyExc_GreenletExit \
        ((PyObject*)_PyGreenlet_API[PyExc_GreenletExit_NUM])

/*
 * PyGreenlet_New(PyObject *args)
 *
 * greenlet.greenlet(run, parent=None)
 */
#    define PyGreenlet_New                                        \
        (*(PyGreenlet * (*)(PyObject * run, PyGreenlet * parent)) \
             _PyGreenlet_API[PyGreenlet_New_NUM])

/*
 * PyGreenlet_GetCurrent(void)
 *
 * greenlet.getcurrent()
 */
#    define PyGreenlet_GetCurrent \
        (*(PyGreenlet * (*)(void)) _PyGreenlet_API[PyGreenlet_GetCurrent_NUM])

/*
 * PyGreenlet_Throw(
 *         PyGreenlet *greenlet,
 *         PyObject *typ,
 *         PyObject *val,
 *         PyObject *tb)
 *
 * g.throw(...)
 */
#    define PyGreenlet_Throw                 \
        (*(PyObject * (*)(PyGreenlet * self, \
                          PyObject * typ,    \
                          PyObject * val,    \
                          PyObject * tb))    \
             _PyGreenlet_API[PyGreenlet_Throw_NUM])

/*
 * PyGreenlet_Switch(PyGreenlet *greenlet, PyObject *args)
 *
 * g.switch(*args, **kwargs)
 */
#    define PyGreenlet_Switch                                              \
        (*(PyObject *                                                      \
           (*)(PyGreenlet * greenlet, PyObject * args, PyObject * kwargs)) \
             _PyGreenlet_API[PyGreenlet_Switch_NUM])

/*
 * PyGreenlet_SetParent(PyObject *greenlet, PyObject *new_parent)
 *
 * g.parent = new_parent
 */
#    define PyGreenlet_SetParent                                 \
        (*(int (*)(PyGreenlet * greenlet, PyGreenlet * nparent)) \
             _PyGreenlet_API[PyGreenlet_SetParent_NUM])

/* Macro that imports greenlet and initializes C API */
/* NOTE: This has actually moved to ``greenlet._greenlet._C_API``, but we
   keep the older definition to be sure older code that might have a copy of
   the header still works. */
#    define PyGreenlet_Import()                                               \
        {                                                                     \
            _PyGreenlet_API = (void**)PyCapsule_Import("greenlet._C_API", 0); \
        }

#endif /* GREENLET_MODULE */

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