1 #ifndef Py_CEVAL_H
2 #define Py_CEVAL_H
3 #ifdef __cplusplus
4 extern "C" {
5 #endif
6 
7 
8 /* Interface to random parts in ceval.c */
9 
10 PyAPI_FUNC(PyObject *) PyEval_CallObjectWithKeywords(
11     PyObject *func, PyObject *args, PyObject *kwargs);
12 
13 /* Inline this */
14 #define PyEval_CallObject(func,arg) \
15     PyEval_CallObjectWithKeywords(func, arg, (PyObject *)NULL)
16 
17 PyAPI_FUNC(PyObject *) PyEval_CallFunction(PyObject *obj,
18                                            const char *format, ...);
19 PyAPI_FUNC(PyObject *) PyEval_CallMethod(PyObject *obj,
20                                          const char *methodname,
21                                          const char *format, ...);
22 
23 #ifndef Py_LIMITED_API
24 PyAPI_FUNC(void) PyEval_SetProfile(Py_tracefunc, PyObject *);
25 PyAPI_FUNC(void) PyEval_SetTrace(Py_tracefunc, PyObject *);
26 PyAPI_FUNC(void) _PyEval_SetCoroutineWrapper(PyObject *);
27 PyAPI_FUNC(PyObject *) _PyEval_GetCoroutineWrapper(void);
28 PyAPI_FUNC(void) _PyEval_SetAsyncGenFirstiter(PyObject *);
29 PyAPI_FUNC(PyObject *) _PyEval_GetAsyncGenFirstiter(void);
30 PyAPI_FUNC(void) _PyEval_SetAsyncGenFinalizer(PyObject *);
31 PyAPI_FUNC(PyObject *) _PyEval_GetAsyncGenFinalizer(void);
32 #endif
33 
34 struct _frame; /* Avoid including frameobject.h */
35 
36 PyAPI_FUNC(PyObject *) PyEval_GetBuiltins(void);
37 PyAPI_FUNC(PyObject *) PyEval_GetGlobals(void);
38 PyAPI_FUNC(PyObject *) PyEval_GetLocals(void);
39 PyAPI_FUNC(struct _frame *) PyEval_GetFrame(void);
40 
41 /* Look at the current frame's (if any) code's co_flags, and turn on
42    the corresponding compiler flags in cf->cf_flags.  Return 1 if any
43    flag was set, else return 0. */
44 #ifndef Py_LIMITED_API
45 PyAPI_FUNC(int) PyEval_MergeCompilerFlags(PyCompilerFlags *cf);
46 #endif
47 
48 PyAPI_FUNC(int) Py_AddPendingCall(int (*func)(void *), void *arg);
49 PyAPI_FUNC(int) Py_MakePendingCalls(void);
50 
51 /* Protection against deeply nested recursive calls
52 
53    In Python 3.0, this protection has two levels:
54    * normal anti-recursion protection is triggered when the recursion level
55      exceeds the current recursion limit. It raises a RecursionError, and sets
56      the "overflowed" flag in the thread state structure. This flag
57      temporarily *disables* the normal protection; this allows cleanup code
58      to potentially outgrow the recursion limit while processing the
59      RecursionError.
60    * "last chance" anti-recursion protection is triggered when the recursion
61      level exceeds "current recursion limit + 50". By construction, this
62      protection can only be triggered when the "overflowed" flag is set. It
63      means the cleanup code has itself gone into an infinite loop, or the
64      RecursionError has been mistakingly ignored. When this protection is
65      triggered, the interpreter aborts with a Fatal Error.
66 
67    In addition, the "overflowed" flag is automatically reset when the
68    recursion level drops below "current recursion limit - 50". This heuristic
69    is meant to ensure that the normal anti-recursion protection doesn't get
70    disabled too long.
71 
72    Please note: this scheme has its own limitations. See:
73    http://mail.python.org/pipermail/python-dev/2008-August/082106.html
74    for some observations.
75 */
76 PyAPI_FUNC(void) Py_SetRecursionLimit(int);
77 PyAPI_FUNC(int) Py_GetRecursionLimit(void);
78 
79 #define Py_EnterRecursiveCall(where)  \
80             (_Py_MakeRecCheck(PyThreadState_GET()->recursion_depth) &&  \
81              _Py_CheckRecursiveCall(where))
82 #define Py_LeaveRecursiveCall()                         \
83     do{ if(_Py_MakeEndRecCheck(PyThreadState_GET()->recursion_depth))  \
84       PyThreadState_GET()->overflowed = 0;  \
85     } while(0)
86 PyAPI_FUNC(int) _Py_CheckRecursiveCall(const char *where);
87 PyAPI_DATA(int) _Py_CheckRecursionLimit;
88 
89 #ifdef USE_STACKCHECK
90 /* With USE_STACKCHECK, we artificially decrement the recursion limit in order
91    to trigger regular stack checks in _Py_CheckRecursiveCall(), except if
92    the "overflowed" flag is set, in which case we need the true value
93    of _Py_CheckRecursionLimit for _Py_MakeEndRecCheck() to function properly.
94 */
95 #  define _Py_MakeRecCheck(x)  \
96     (++(x) > (_Py_CheckRecursionLimit += PyThreadState_GET()->overflowed - 1))
97 #else
98 #  define _Py_MakeRecCheck(x)  (++(x) > _Py_CheckRecursionLimit)
99 #endif
100 
101 /* Compute the "lower-water mark" for a recursion limit. When
102  * Py_LeaveRecursiveCall() is called with a recursion depth below this mark,
103  * the overflowed flag is reset to 0. */
104 #define _Py_RecursionLimitLowerWaterMark(limit) \
105     (((limit) > 200) \
106         ? ((limit) - 50) \
107         : (3 * ((limit) >> 2)))
108 
109 #define _Py_MakeEndRecCheck(x) \
110     (--(x) < _Py_RecursionLimitLowerWaterMark(_Py_CheckRecursionLimit))
111 
112 #define Py_ALLOW_RECURSION \
113   do { unsigned char _old = PyThreadState_GET()->recursion_critical;\
114     PyThreadState_GET()->recursion_critical = 1;
115 
116 #define Py_END_ALLOW_RECURSION \
117     PyThreadState_GET()->recursion_critical = _old; \
118   } while(0);
119 
120 PyAPI_FUNC(const char *) PyEval_GetFuncName(PyObject *);
121 PyAPI_FUNC(const char *) PyEval_GetFuncDesc(PyObject *);
122 
123 PyAPI_FUNC(PyObject *) PyEval_GetCallStats(PyObject *);
124 PyAPI_FUNC(PyObject *) PyEval_EvalFrame(struct _frame *);
125 PyAPI_FUNC(PyObject *) PyEval_EvalFrameEx(struct _frame *f, int exc);
126 #ifndef Py_LIMITED_API
127 PyAPI_FUNC(PyObject *) _PyEval_EvalFrameDefault(struct _frame *f, int exc);
128 #endif
129 
130 /* Interface for threads.
131 
132    A module that plans to do a blocking system call (or something else
133    that lasts a long time and doesn't touch Python data) can allow other
134    threads to run as follows:
135 
136     ...preparations here...
137     Py_BEGIN_ALLOW_THREADS
138     ...blocking system call here...
139     Py_END_ALLOW_THREADS
140     ...interpret result here...
141 
142    The Py_BEGIN_ALLOW_THREADS/Py_END_ALLOW_THREADS pair expands to a
143    {}-surrounded block.
144    To leave the block in the middle (e.g., with return), you must insert
145    a line containing Py_BLOCK_THREADS before the return, e.g.
146 
147     if (...premature_exit...) {
148         Py_BLOCK_THREADS
149         PyErr_SetFromErrno(PyExc_IOError);
150         return NULL;
151     }
152 
153    An alternative is:
154 
155     Py_BLOCK_THREADS
156     if (...premature_exit...) {
157         PyErr_SetFromErrno(PyExc_IOError);
158         return NULL;
159     }
160     Py_UNBLOCK_THREADS
161 
162    For convenience, that the value of 'errno' is restored across
163    Py_END_ALLOW_THREADS and Py_BLOCK_THREADS.
164 
165    WARNING: NEVER NEST CALLS TO Py_BEGIN_ALLOW_THREADS AND
166    Py_END_ALLOW_THREADS!!!
167 
168    The function PyEval_InitThreads() should be called only from
169    init_thread() in "_threadmodule.c".
170 
171    Note that not yet all candidates have been converted to use this
172    mechanism!
173 */
174 
175 PyAPI_FUNC(PyThreadState *) PyEval_SaveThread(void);
176 PyAPI_FUNC(void) PyEval_RestoreThread(PyThreadState *);
177 
178 #ifdef WITH_THREAD
179 
180 PyAPI_FUNC(int)  PyEval_ThreadsInitialized(void);
181 PyAPI_FUNC(void) PyEval_InitThreads(void);
182 #ifndef Py_LIMITED_API
183 PyAPI_FUNC(void) _PyEval_FiniThreads(void);
184 #endif /* !Py_LIMITED_API */
185 PyAPI_FUNC(void) PyEval_AcquireLock(void);
186 PyAPI_FUNC(void) PyEval_ReleaseLock(void);
187 PyAPI_FUNC(void) PyEval_AcquireThread(PyThreadState *tstate);
188 PyAPI_FUNC(void) PyEval_ReleaseThread(PyThreadState *tstate);
189 PyAPI_FUNC(void) PyEval_ReInitThreads(void);
190 
191 #ifndef Py_LIMITED_API
192 PyAPI_FUNC(void) _PyEval_SetSwitchInterval(unsigned long microseconds);
193 PyAPI_FUNC(unsigned long) _PyEval_GetSwitchInterval(void);
194 #endif
195 
196 #ifndef Py_LIMITED_API
197 PyAPI_FUNC(Py_ssize_t) _PyEval_RequestCodeExtraIndex(freefunc);
198 #endif
199 
200 #define Py_BEGIN_ALLOW_THREADS { \
201                         PyThreadState *_save; \
202                         _save = PyEval_SaveThread();
203 #define Py_BLOCK_THREADS        PyEval_RestoreThread(_save);
204 #define Py_UNBLOCK_THREADS      _save = PyEval_SaveThread();
205 #define Py_END_ALLOW_THREADS    PyEval_RestoreThread(_save); \
206                  }
207 
208 #else /* !WITH_THREAD */
209 
210 #define Py_BEGIN_ALLOW_THREADS {
211 #define Py_BLOCK_THREADS
212 #define Py_UNBLOCK_THREADS
213 #define Py_END_ALLOW_THREADS }
214 
215 #endif /* !WITH_THREAD */
216 
217 #ifndef Py_LIMITED_API
218 PyAPI_FUNC(int) _PyEval_SliceIndex(PyObject *, Py_ssize_t *);
219 PyAPI_FUNC(void) _PyEval_SignalAsyncExc(void);
220 #endif
221 
222 /* Masks and values used by FORMAT_VALUE opcode. */
223 #define FVC_MASK      0x3
224 #define FVC_NONE      0x0
225 #define FVC_STR       0x1
226 #define FVC_REPR      0x2
227 #define FVC_ASCII     0x3
228 #define FVS_MASK      0x4
229 #define FVS_HAVE_SPEC 0x4
230 
231 #ifdef __cplusplus
232 }
233 #endif
234 #endif /* !Py_CEVAL_H */
235