cpython/Include/ceval.h

#ifndef Py_CEVAL_H
#define Py_CEVAL_H
#ifdef __cplusplus
extern "C" {
#endif


/* Interface to random parts in ceval.c */

PyAPI_FUNC(PyObject *) PyEval_CallObjectWithKeywords(
	PyObject *, PyObject *, PyObject *);

/* DLL-level Backwards compatibility: */
#undef PyEval_CallObject
PyAPI_FUNC(PyObject *) PyEval_CallObject(PyObject *, PyObject *);

/* Inline this */
#define PyEval_CallObject(func,arg) \
        PyEval_CallObjectWithKeywords(func, arg, (PyObject *)NULL)

PyAPI_FUNC(PyObject *) PyEval_CallFunction(PyObject *obj,
                                           const char *format, ...);
PyAPI_FUNC(PyObject *) PyEval_CallMethod(PyObject *obj,
                                         const char *methodname,
                                         const char *format, ...);

PyAPI_FUNC(void) PyEval_SetProfile(Py_tracefunc, PyObject *);
PyAPI_FUNC(void) PyEval_SetTrace(Py_tracefunc, PyObject *);

struct _frame; /* Avoid including frameobject.h */

PyAPI_FUNC(PyObject *) PyEval_GetBuiltins(void);
PyAPI_FUNC(PyObject *) PyEval_GetGlobals(void);
PyAPI_FUNC(PyObject *) PyEval_GetLocals(void);
PyAPI_FUNC(struct _frame *) PyEval_GetFrame(void);

/* Look at the current frame's (if any) code's co_flags, and turn on
   the corresponding compiler flags in cf->cf_flags.  Return 1 if any
   flag was set, else return 0. */
PyAPI_FUNC(int) PyEval_MergeCompilerFlags(PyCompilerFlags *cf);

PyAPI_FUNC(int) Py_AddPendingCall(int (*func)(void *), void *arg);
PyAPI_FUNC(int) Py_MakePendingCalls(void);

/* Protection against deeply nested recursive calls */
PyAPI_FUNC(void) Py_SetRecursionLimit(int);
PyAPI_FUNC(int) Py_GetRecursionLimit(void);

#define Py_EnterRecursiveCall(where)                                    \
	    (_Py_MakeRecCheck(PyThreadState_GET()->recursion_depth) &&  \
	     _Py_CheckRecursiveCall(where))
#define Py_LeaveRecursiveCall()				\
    do{ if((--PyThreadState_GET()->recursion_depth) <   \
	   _Py_CheckRecursionLimit - 50)                \
	  PyThreadState_GET()->overflowed = 0;          \
    } while(0)
PyAPI_FUNC(int) _Py_CheckRecursiveCall(char *where);
PyAPI_DATA(int) _Py_CheckRecursionLimit;
#ifdef USE_STACKCHECK
#  define _Py_MakeRecCheck(x)  (++(x) > --_Py_CheckRecursionLimit)
#else
#  define _Py_MakeRecCheck(x)  (++(x) > _Py_CheckRecursionLimit)
#endif

#define Py_ALLOW_RECURSION \
  do { unsigned char _old = PyThreadState_GET()->recursion_critical;\
    PyThreadState_GET()->recursion_critical = 1;

#define Py_END_ALLOW_RECURSION \
    PyThreadState_GET()->recursion_critical = _old; \
  } while(0);

PyAPI_FUNC(const char *) PyEval_GetFuncName(PyObject *);
PyAPI_FUNC(const char *) PyEval_GetFuncDesc(PyObject *);

PyAPI_FUNC(PyObject *) PyEval_GetCallStats(PyObject *);
PyAPI_FUNC(PyObject *) PyEval_EvalFrame(struct _frame *);
PyAPI_FUNC(PyObject *) PyEval_EvalFrameEx(struct _frame *f, int exc);

/* this used to be handled on a per-thread basis - now just two globals */
PyAPI_DATA(volatile int) _Py_Ticker;
PyAPI_DATA(int) _Py_CheckInterval;

/* Interface for threads.

   A module that plans to do a blocking system call (or something else
   that lasts a long time and doesn't touch Python data) can allow other
   threads to run as follows:

	...preparations here...
	Py_BEGIN_ALLOW_THREADS
	...blocking system call here...
	Py_END_ALLOW_THREADS
	...interpret result here...

   The Py_BEGIN_ALLOW_THREADS/Py_END_ALLOW_THREADS pair expands to a
   {}-surrounded block.
   To leave the block in the middle (e.g., with return), you must insert
   a line containing Py_BLOCK_THREADS before the return, e.g.

	if (...premature_exit...) {
		Py_BLOCK_THREADS
		PyErr_SetFromErrno(PyExc_IOError);
		return NULL;
	}

   An alternative is:

	Py_BLOCK_THREADS
	if (...premature_exit...) {
		PyErr_SetFromErrno(PyExc_IOError);
		return NULL;
	}
	Py_UNBLOCK_THREADS

   For convenience, that the value of 'errno' is restored across
   Py_END_ALLOW_THREADS and Py_BLOCK_THREADS.

   WARNING: NEVER NEST CALLS TO Py_BEGIN_ALLOW_THREADS AND
   Py_END_ALLOW_THREADS!!!

   The function PyEval_InitThreads() should be called only from
   initthread() in "threadmodule.c".

   Note that not yet all candidates have been converted to use this
   mechanism!
*/

PyAPI_FUNC(PyThreadState *) PyEval_SaveThread(void);
PyAPI_FUNC(void) PyEval_RestoreThread(PyThreadState *);

#ifdef WITH_THREAD

PyAPI_FUNC(int)  PyEval_ThreadsInitialized(void);
PyAPI_FUNC(void) PyEval_InitThreads(void);
PyAPI_FUNC(void) PyEval_AcquireLock(void);
PyAPI_FUNC(void) PyEval_ReleaseLock(void);
PyAPI_FUNC(void) PyEval_AcquireThread(PyThreadState *tstate);
PyAPI_FUNC(void) PyEval_ReleaseThread(PyThreadState *tstate);
PyAPI_FUNC(void) PyEval_ReInitThreads(void);

#define Py_BEGIN_ALLOW_THREADS { \
			PyThreadState *_save; \
			_save = PyEval_SaveThread();
#define Py_BLOCK_THREADS	PyEval_RestoreThread(_save);
#define Py_UNBLOCK_THREADS	_save = PyEval_SaveThread();
#define Py_END_ALLOW_THREADS	PyEval_RestoreThread(_save); \
		 }

#else /* !WITH_THREAD */

#define Py_BEGIN_ALLOW_THREADS {
#define Py_BLOCK_THREADS
#define Py_UNBLOCK_THREADS
#define Py_END_ALLOW_THREADS }

#endif /* !WITH_THREAD */

PyAPI_FUNC(int) _PyEval_SliceIndex(PyObject *, Py_ssize_t *);


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