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Guido van Rossuma3309961993-07-28 09:05:47 +00001#ifndef Py_CEVAL_H
2#define Py_CEVAL_H
3#ifdef __cplusplus
4extern "C" {
5#endif
6
Guido van Rossumf70e43a1991-02-19 12:39:46 +00007/***********************************************************
Guido van Rossum5799b521995-01-04 19:06:22 +00008Copyright 1991-1995 by Stichting Mathematisch Centrum, Amsterdam,
9The Netherlands.
Guido van Rossumf70e43a1991-02-19 12:39:46 +000010
11 All Rights Reserved
12
Guido van Rossumd266eb41996-10-25 14:44:06 +000013Permission to use, copy, modify, and distribute this software and its
14documentation for any purpose and without fee is hereby granted,
Guido van Rossumf70e43a1991-02-19 12:39:46 +000015provided that the above copyright notice appear in all copies and that
Guido van Rossumd266eb41996-10-25 14:44:06 +000016both that copyright notice and this permission notice appear in
Guido van Rossumf70e43a1991-02-19 12:39:46 +000017supporting documentation, and that the names of Stichting Mathematisch
Guido van Rossumd266eb41996-10-25 14:44:06 +000018Centrum or CWI or Corporation for National Research Initiatives or
19CNRI not be used in advertising or publicity pertaining to
20distribution of the software without specific, written prior
21permission.
Guido van Rossumf70e43a1991-02-19 12:39:46 +000022
Guido van Rossumd266eb41996-10-25 14:44:06 +000023While CWI is the initial source for this software, a modified version
24is made available by the Corporation for National Research Initiatives
25(CNRI) at the Internet address ftp://ftp.python.org.
26
27STICHTING MATHEMATISCH CENTRUM AND CNRI DISCLAIM ALL WARRANTIES WITH
28REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF
29MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH
30CENTRUM OR CNRI BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL
31DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
32PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
33TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
34PERFORMANCE OF THIS SOFTWARE.
Guido van Rossumf70e43a1991-02-19 12:39:46 +000035
36******************************************************************/
37
Guido van Rossumff4949e1992-08-05 19:58:53 +000038/* Interface to random parts in ceval.c */
Guido van Rossum3f5da241990-12-20 15:06:42 +000039
Guido van Rossumcaa63801995-01-12 11:45:45 +000040PyObject *PyEval_CallObject Py_PROTO((PyObject *, PyObject *));
Guido van Rossum884afd61995-07-18 14:21:06 +000041PyObject *PyEval_CallObjectWithKeywords
42 Py_PROTO((PyObject *, PyObject *, PyObject *));
Guido van Rossuma0490311991-07-27 21:33:03 +000043
Guido van Rossumcaa63801995-01-12 11:45:45 +000044PyObject *PyEval_GetBuiltins Py_PROTO((void));
45PyObject *PyEval_GetGlobals Py_PROTO((void));
46PyObject *PyEval_GetLocals Py_PROTO((void));
47PyObject *PyEval_GetOwner Py_PROTO((void));
48PyObject *PyEval_GetFrame Py_PROTO((void));
49int PyEval_GetRestricted Py_PROTO((void));
Guido van Rossum3f5da241990-12-20 15:06:42 +000050
Guido van Rossumcaa63801995-01-12 11:45:45 +000051void Py_FlushLine Py_PROTO((void));
Guido van Rossumff4949e1992-08-05 19:58:53 +000052
Guido van Rossumcaa63801995-01-12 11:45:45 +000053int Py_AddPendingCall Py_PROTO((int (*func) Py_PROTO((ANY *)), ANY *arg));
54int Py_MakePendingCalls Py_PROTO((void));
Guido van Rossum95664081994-09-14 13:23:36 +000055
Guido van Rossumff4949e1992-08-05 19:58:53 +000056
57/* Interface for threads.
58
59 A module that plans to do a blocking system call (or something else
60 that lasts a long time and doesn't touch Python data) can allow other
61 threads to run as follows:
62
63 ...preparations here...
Guido van Rossumcaa63801995-01-12 11:45:45 +000064 Py_BEGIN_ALLOW_THREADS
Guido van Rossumff4949e1992-08-05 19:58:53 +000065 ...blocking system call here...
Guido van Rossumcaa63801995-01-12 11:45:45 +000066 Py_END_ALLOW_THREADS
Guido van Rossum66cb3111994-12-30 15:33:50 +000067 ...interpret result here...
Guido van Rossumff4949e1992-08-05 19:58:53 +000068
Guido van Rossumcaa63801995-01-12 11:45:45 +000069 The Py_BEGIN_ALLOW_THREADS/Py_END_ALLOW_THREADS pair expands to a
70 {}-surrounded block.
Guido van Rossumff4949e1992-08-05 19:58:53 +000071 To leave the block in the middle (e.g., with return), you must insert
72 a line containing RET_SAVE before the return, e.g.
73
74 if (...premature_exit...) {
Guido van Rossumcaa63801995-01-12 11:45:45 +000075 Py_BLOCK_THREADS
76 PyErr_SetFromErrno(PyExc_IOError);
Guido van Rossumff4949e1992-08-05 19:58:53 +000077 return NULL;
78 }
79
80 An alternative is:
81
Guido van Rossumcaa63801995-01-12 11:45:45 +000082 Py_BLOCK_THREADS
Guido van Rossumff4949e1992-08-05 19:58:53 +000083 if (...premature_exit...) {
Guido van Rossumcaa63801995-01-12 11:45:45 +000084 PyErr_SetFromErrno(PyExc_IOError);
Guido van Rossumff4949e1992-08-05 19:58:53 +000085 return NULL;
86 }
Guido van Rossumcaa63801995-01-12 11:45:45 +000087 Py_UNBLOCK_THREADS
Guido van Rossumff4949e1992-08-05 19:58:53 +000088
89 For convenience, that the value of 'errno' is restored across
Guido van Rossumcaa63801995-01-12 11:45:45 +000090 Py_END_ALLOW_THREADS and RET_SAVE.
Guido van Rossumff4949e1992-08-05 19:58:53 +000091
Guido van Rossumcaa63801995-01-12 11:45:45 +000092 WARNING: NEVER NEST CALLS TO Py_BEGIN_ALLOW_THREADS AND
93 Py_END_ALLOW_THREADS!!!
Guido van Rossumff4949e1992-08-05 19:58:53 +000094
Guido van Rossumcaa63801995-01-12 11:45:45 +000095 The function PyEval_InitThreads() should be called only from
Guido van Rossumff4949e1992-08-05 19:58:53 +000096 initthread() in "threadmodule.c".
97
98 Note that not yet all candidates have been converted to use this
99 mechanism!
100*/
101
Guido van Rossumcaa63801995-01-12 11:45:45 +0000102extern void PyEval_InitThreads Py_PROTO((void));
103extern PyObject *PyEval_SaveThread Py_PROTO((void));
104extern void PyEval_RestoreThread Py_PROTO((PyObject *));
Guido van Rossumff4949e1992-08-05 19:58:53 +0000105
Guido van Rossumb6775db1994-08-01 11:34:53 +0000106#ifdef WITH_THREAD
Guido van Rossumff4949e1992-08-05 19:58:53 +0000107
Guido van Rossumcaa63801995-01-12 11:45:45 +0000108#define Py_BEGIN_ALLOW_THREADS { \
109 PyObject *_save; \
110 _save = PyEval_SaveThread();
111#define Py_BLOCK_THREADS PyEval_RestoreThread(_save);
112#define Py_UNBLOCK_THREADS _save = PyEval_SaveThread();
113#define Py_END_ALLOW_THREADS PyEval_RestoreThread(_save); \
Guido van Rossumff4949e1992-08-05 19:58:53 +0000114 }
115
Guido van Rossumb6775db1994-08-01 11:34:53 +0000116#else /* !WITH_THREAD */
Guido van Rossumff4949e1992-08-05 19:58:53 +0000117
Guido van Rossumcaa63801995-01-12 11:45:45 +0000118#define Py_BEGIN_ALLOW_THREADS {
119#define Py_BLOCK_THREADS
120#define Py_UNBLOCK_THREADS
121#define Py_END_ALLOW_THREADS }
Guido van Rossumff4949e1992-08-05 19:58:53 +0000122
Guido van Rossumb6775db1994-08-01 11:34:53 +0000123#endif /* !WITH_THREAD */
Guido van Rossuma3309961993-07-28 09:05:47 +0000124
125#ifdef __cplusplus
126}
127#endif
128#endif /* !Py_CEVAL_H */