1#ifndef Py_CEVAL_H
2#define Py_CEVAL_H
3#ifdef __cplusplus
4extern "C" {
5#endif
6
7
8/* Interface to random parts in ceval.c */
9
10PyAPI_FUNC(PyObject *) PyEval_CallObjectWithKeywords(
11 PyObject *, PyObject *, PyObject *);
12
13/* Inline this */
14#define PyEval_CallObject(func,arg) \
15 PyEval_CallObjectWithKeywords(func, arg, (PyObject *)NULL)
16
17PyAPI_FUNC(PyObject *) PyEval_CallFunction(PyObject *obj,
18 const char *format, ...);
19PyAPI_FUNC(PyObject *) PyEval_CallMethod(PyObject *obj,
20 const char *methodname,
21 const char *format, ...);
22
23#ifndef Py_LIMITED_API
24PyAPI_FUNC(void) PyEval_SetProfile(Py_tracefunc, PyObject *);
25PyAPI_FUNC(void) PyEval_SetTrace(Py_tracefunc, PyObject *);
26PyAPI_FUNC(void) _PyEval_SetCoroutineWrapper(PyObject *);
27PyAPI_FUNC(PyObject *) _PyEval_GetCoroutineWrapper(void);
28#endif
29
30struct _frame; /* Avoid including frameobject.h */
31
32PyAPI_FUNC(PyObject *) PyEval_GetBuiltins(void);
33PyAPI_FUNC(PyObject *) PyEval_GetGlobals(void);
34PyAPI_FUNC(PyObject *) PyEval_GetLocals(void);
35PyAPI_FUNC(struct _frame *) PyEval_GetFrame(void);
36
37/* Look at the current frame's (if any) code's co_flags, and turn on
38 the corresponding compiler flags in cf->cf_flags. Return 1 if any
39 flag was set, else return 0. */
40#ifndef Py_LIMITED_API
41PyAPI_FUNC(int) PyEval_MergeCompilerFlags(PyCompilerFlags *cf);
42#endif
43
44PyAPI_FUNC(int) Py_AddPendingCall(int (*func)(void *), void *arg);
45PyAPI_FUNC(int) Py_MakePendingCalls(void);
46
47/* Protection against deeply nested recursive calls
48
49 In Python 3.0, this protection has two levels:
50 * normal anti-recursion protection is triggered when the recursion level
51 exceeds the current recursion limit. It raises a RecursionError, and sets
52 the "overflowed" flag in the thread state structure. This flag
53 temporarily *disables* the normal protection; this allows cleanup code
54 to potentially outgrow the recursion limit while processing the
55 RecursionError.
56 * "last chance" anti-recursion protection is triggered when the recursion
57 level exceeds "current recursion limit + 50". By construction, this
58 protection can only be triggered when the "overflowed" flag is set. It
59 means the cleanup code has itself gone into an infinite loop, or the
60 RecursionError has been mistakingly ignored. When this protection is
61 triggered, the interpreter aborts with a Fatal Error.
62
63 In addition, the "overflowed" flag is automatically reset when the
64 recursion level drops below "current recursion limit - 50". This heuristic
65 is meant to ensure that the normal anti-recursion protection doesn't get
66 disabled too long.
67
68 Please note: this scheme has its own limitations. See:
69 http://mail.python.org/pipermail/python-dev/2008-August/082106.html
70 for some observations.
71*/
72PyAPI_FUNC(void) Py_SetRecursionLimit(int);
73PyAPI_FUNC(int) Py_GetRecursionLimit(void);
74
75#define Py_EnterRecursiveCall(where) \
76 (_Py_MakeRecCheck(PyThreadState_GET()->recursion_depth) && \
77 _Py_CheckRecursiveCall(where))
78#define Py_LeaveRecursiveCall() \
79 do{ if(_Py_MakeEndRecCheck(PyThreadState_GET()->recursion_depth)) \
80 PyThreadState_GET()->overflowed = 0; \
81 } while(0)
82PyAPI_FUNC(int) _Py_CheckRecursiveCall(const char *where);
83PyAPI_DATA(int) _Py_CheckRecursionLimit;
84
85#ifdef USE_STACKCHECK
86/* With USE_STACKCHECK, we artificially decrement the recursion limit in order
87 to trigger regular stack checks in _Py_CheckRecursiveCall(), except if
88 the "overflowed" flag is set, in which case we need the true value
89 of _Py_CheckRecursionLimit for _Py_MakeEndRecCheck() to function properly.
90*/
91# define _Py_MakeRecCheck(x) \
92 (++(x) > (_Py_CheckRecursionLimit += PyThreadState_GET()->overflowed - 1))
93#else
94# define _Py_MakeRecCheck(x) (++(x) > _Py_CheckRecursionLimit)
95#endif
96
97/* Compute the "lower-water mark" for a recursion limit. When
98 * Py_LeaveRecursiveCall() is called with a recursion depth below this mark,
99 * the overflowed flag is reset to 0. */
100#define _Py_RecursionLimitLowerWaterMark(limit) \
101 (((limit) > 200) \
102 ? ((limit) - 50) \
103 : (3 * ((limit) >> 2)))
104
105#define _Py_MakeEndRecCheck(x) \
106 (--(x) < _Py_RecursionLimitLowerWaterMark(_Py_CheckRecursionLimit))
107
108#define Py_ALLOW_RECURSION \
109 do { unsigned char _old = PyThreadState_GET()->recursion_critical;\
110 PyThreadState_GET()->recursion_critical = 1;
111
112#define Py_END_ALLOW_RECURSION \
113 PyThreadState_GET()->recursion_critical = _old; \
114 } while(0);
115
116PyAPI_FUNC(const char *) PyEval_GetFuncName(PyObject *);
117PyAPI_FUNC(const char *) PyEval_GetFuncDesc(PyObject *);
118
119PyAPI_FUNC(PyObject *) PyEval_GetCallStats(PyObject *);
120PyAPI_FUNC(PyObject *) PyEval_EvalFrame(struct _frame *);
121PyAPI_FUNC(PyObject *) PyEval_EvalFrameEx(struct _frame *f, int exc);
122
123/* Interface for threads.
124
125 A module that plans to do a blocking system call (or something else
126 that lasts a long time and doesn't touch Python data) can allow other
127 threads to run as follows:
128
129 ...preparations here...
130 Py_BEGIN_ALLOW_THREADS
131 ...blocking system call here...
132 Py_END_ALLOW_THREADS
133 ...interpret result here...
134
135 The Py_BEGIN_ALLOW_THREADS/Py_END_ALLOW_THREADS pair expands to a
136 {}-surrounded block.
137 To leave the block in the middle (e.g., with return), you must insert
138 a line containing Py_BLOCK_THREADS before the return, e.g.
139
140 if (...premature_exit...) {
141 Py_BLOCK_THREADS
142 PyErr_SetFromErrno(PyExc_IOError);
143 return NULL;
144 }
145
146 An alternative is:
147
148 Py_BLOCK_THREADS
149 if (...premature_exit...) {
150 PyErr_SetFromErrno(PyExc_IOError);
151 return NULL;
152 }
153 Py_UNBLOCK_THREADS
154
155 For convenience, that the value of 'errno' is restored across
156 Py_END_ALLOW_THREADS and Py_BLOCK_THREADS.
157
158 WARNING: NEVER NEST CALLS TO Py_BEGIN_ALLOW_THREADS AND
159 Py_END_ALLOW_THREADS!!!
160
161 The function PyEval_InitThreads() should be called only from
162 init_thread() in "_threadmodule.c".
163
164 Note that not yet all candidates have been converted to use this
165 mechanism!
166*/
167
168PyAPI_FUNC(PyThreadState *) PyEval_SaveThread(void);
169PyAPI_FUNC(void) PyEval_RestoreThread(PyThreadState *);
170
171#ifdef WITH_THREAD
172
173PyAPI_FUNC(int) PyEval_ThreadsInitialized(void);
174PyAPI_FUNC(void) PyEval_InitThreads(void);
175PyAPI_FUNC(void) _PyEval_FiniThreads(void);
176PyAPI_FUNC(void) PyEval_AcquireLock(void);
177PyAPI_FUNC(void) PyEval_ReleaseLock(void);
178PyAPI_FUNC(void) PyEval_AcquireThread(PyThreadState *tstate);
179PyAPI_FUNC(void) PyEval_ReleaseThread(PyThreadState *tstate);
180PyAPI_FUNC(void) PyEval_ReInitThreads(void);
181
182#ifndef Py_LIMITED_API
183PyAPI_FUNC(void) _PyEval_SetSwitchInterval(unsigned long microseconds);
184PyAPI_FUNC(unsigned long) _PyEval_GetSwitchInterval(void);
185#endif
186
187#define Py_BEGIN_ALLOW_THREADS { \
188 PyThreadState *_save; \
189 _save = PyEval_SaveThread();
190#define Py_BLOCK_THREADS PyEval_RestoreThread(_save);
191#define Py_UNBLOCK_THREADS _save = PyEval_SaveThread();
192#define Py_END_ALLOW_THREADS PyEval_RestoreThread(_save); \
193 }
194
195#else /* !WITH_THREAD */
196
197#define Py_BEGIN_ALLOW_THREADS {
198#define Py_BLOCK_THREADS
199#define Py_UNBLOCK_THREADS
200#define Py_END_ALLOW_THREADS }
201
202#endif /* !WITH_THREAD */
203
204#ifndef Py_LIMITED_API
205PyAPI_FUNC(int) _PyEval_SliceIndex(PyObject *, Py_ssize_t *);
206PyAPI_FUNC(void) _PyEval_SignalAsyncExc(void);
207#endif
208
209
210#ifdef __cplusplus
211}
212#endif
213#endif /* !Py_CEVAL_H */
214