pyke/, ...: Extract utilities into a sort-of reusable library.
[pyke] / pyke.h
1 /* -*-c-*-
2 *
3 * Pyke: the Python Kit for Extensions
4 *
5 * (c) 2019 Straylight/Edgeware
6 */
7
8 /*----- Licensing notice --------------------------------------------------*
9 *
10 * This file is part of Pyke: the Python Kit for Extensions.
11 *
12 * Pyke is free software: you can redistribute it and/or modify it under
13 * the terms of the GNU General Public License as published by the Free
14 * Software Foundation; either version 2 of the License, or (at your
15 * option) any later version.
16 *
17 * Pyke is distributed in the hope that it will be useful, but WITHOUT
18 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
19 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
20 * for more details.
21 *
22 * You should have received a copy of the GNU General Public License
23 * along with Pyke. If not, write to the Free Software Foundation, Inc.,
24 * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
25 */
26
27 #ifndef PYKE_H
28 #define PYKE_H
29
30 #ifdef __cplusplus
31 extern "C" {
32 #endif
33
34 /*----- Header files ------------------------------------------------------*/
35
36 #define PY_SSIZE_T_CLEAN
37
38 #include <Python.h>
39 #include <structmember.h>
40
41 /*----- Other preliminaries -----------------------------------------------*/
42
43 #define NOTHING
44 #define COMMA ,
45
46 /*----- Symbol visibility -------------------------------------------------*
47 *
48 * This library is very messy regarding symbol namespace. Keep this mess
49 * within our shared-object.
50 */
51
52 #define GOBBLE_SEMI extern int notexist
53 #if defined(__GNUC__) && defined(__ELF__)
54 # define PRIVATE_SYMBOLS _Pragma("GCC visibility push(hidden)") GOBBLE_SEMI
55 # define PUBLIC_SYMBOLS _Pragma("GCC visibility pop") GOBBLE_SEMI
56 # define EXPORT __attribute__((__visibility__("default")))
57 #else
58 # define PRIVATE_SYMBOLS GOBBLE_SEMI
59 # define PUBLIC_SYMBOLS GOBBLE_SEMI
60 # define EXPORT
61 #endif
62
63 PRIVATE_SYMBOLS;
64
65 /*----- Utilities for returning values and exceptions ---------------------*/
66
67 /* Returning values. */
68 #define RETURN_OBJ(obj) do { Py_INCREF(obj); return (obj); } while (0)
69 #define RETURN_NONE RETURN_OBJ(Py_None)
70 #define RETURN_NOTIMPL RETURN_OBJ(Py_NotImplemented)
71 #define RETURN_TRUE RETURN_OBJ(Py_True)
72 #define RETURN_FALSE RETURN_OBJ(Py_False)
73 #define RETURN_ME RETURN_OBJ(me)
74
75 /* Returning exceptions. (Note that `KeyError' is `MAPERR' here, because
76 * Catacomb has its own kind of `KeyError'.)
77 */
78 #define EXCERR(exc, str) do { \
79 PyErr_SetString(exc, str); \
80 goto end; \
81 } while (0)
82 #define VALERR(str) EXCERR(PyExc_ValueError, str)
83 #define OVFERR(str) EXCERR(PyExc_OverflowError, str)
84 #define TYERR(str) EXCERR(PyExc_TypeError, str)
85 #define IXERR(str) EXCERR(PyExc_IndexError, str)
86 #define ZDIVERR(str) EXCERR(PyExc_ZeroDivisionError, str)
87 #define SYSERR(str) EXCERR(PyExc_SystemError, str)
88 #define NIERR(str) EXCERR(PyExc_NotImplementedError, str)
89 #define INDEXERR(idx) do { \
90 PyErr_SetObject(PyExc_KeyError, idx); \
91 goto end; \
92 } while (0)
93 #define OSERR(name) do { \
94 PyErr_SetFromErrnoWithFilename(PyExc_OSError, name); \
95 goto end; \
96 } while (0)
97
98 /* Saving and restoring exceptions. */
99 struct excinfo { PyObject *ty, *val, *tb; };
100 #define EXCINFO_INIT { 0, 0, 0 }
101 #define INIT_EXCINFO(exc) do { \
102 struct excinfo *_exc = (exc); _exc->ty = _exc->val = _exc->tb = 0; \
103 } while (0)
104 #define RELEASE_EXCINFO(exc) do { \
105 struct excinfo *_exc = (exc); \
106 Py_XDECREF(_exc->ty); _exc->ty = 0; \
107 Py_XDECREF(_exc->val); _exc->val = 0; \
108 Py_XDECREF(_exc->tb); _exc->tb = 0; \
109 } while (0)
110 #define STASH_EXCINFO(exc) do { \
111 struct excinfo *_exc = (exc); \
112 PyErr_Fetch(&_exc->ty, &_exc->val, &_exc->tb); \
113 PyErr_NormalizeException(&_exc->ty, &_exc->val, &_exc->tb); \
114 } while (0)
115 #define RESTORE_EXCINFO(exc) do { \
116 struct excinfo *_exc = (exc); \
117 PyErr_Restore(_exc->ty, _exc->val, _exc->tb); \
118 _exc->ty = _exc->val = _exc->tb = 0; \
119 } while (0)
120 extern void report_lost_exception(struct excinfo *, const char *, ...);
121 extern void report_lost_exception_v(struct excinfo *, const char *, va_list);
122 extern void stash_exception(struct excinfo *, const char *, ...);
123 extern void restore_exception(struct excinfo *, const char *, ...);
124
125 /*----- Conversions -------------------------------------------------------*/
126
127 /* Define an input conversion (`O&') function: check that the object has
128 * Python type TY, and extract a C pointer to CTY by calling EXT on the
129 * object (which may well be a macro).
130 */
131 #define CONVFUNC(ty, cty, ext) \
132 int conv##ty(PyObject *o, void *p) \
133 { \
134 if (!PyObject_TypeCheck(o, ty##_pytype)) \
135 TYERR("wanted a " #ty); \
136 *(cty *)p = ext(o); \
137 return (1); \
138 end: \
139 return (0); \
140 }
141
142 /* Input conversion functions for standard kinds of objects, with overflow
143 * checking where applicable.
144 */
145 extern int convulong(PyObject *, void *); /* unsigned long */
146 extern int convuint(PyObject *, void *); /* unsigned int */
147 extern int convszt(PyObject *, void *); /* size_t */
148 extern int convbool(PyObject *, void *); /* bool */
149
150 /* Output conversions. */
151 extern PyObject *getbool(int); /* bool */
152 extern PyObject *getulong(unsigned long); /* any kind of unsigned integer */
153
154 /*----- Miscellaneous utilities -------------------------------------------*/
155
156 #define FREEOBJ(obj) \
157 (((PyObject *)(obj))->ob_type->tp_free((PyObject *)(obj)))
158 /* Actually free OBJ, e.g., in a deallocation function. */
159
160 extern PyObject *abstract_pynew(PyTypeObject *, PyObject *, PyObject *);
161 /* A `tp_new' function which refuses to make the object. */
162
163 #define KWLIST (/*unconst*/ char **)kwlist
164 /* Strip `const' qualifiers from the keyword list `kwlist'. Useful when
165 * calling `PyArg_ParseTupleAndKeywords', which isn't `const'-correct.
166 */
167
168 /*----- Type definitions --------------------------------------------------*
169 *
170 * Pyke types are defined in a rather unusual way.
171 *
172 * The main code defines a `type skeleton' of type `PyTypeObject',
173 * conventionally named `TY_pytype_skel'. Unlike typical Python type
174 * definitions in extensions, this can (and should) be read-only. Also,
175 * there's no point in setting the `tp_base' pointer here, because the actual
176 * runtime base type object won't, in general, be known at compile time.
177 * Instead, the type skeletons are converted into Python `heap types' by the
178 * `INITTYPE' macro. The main difference is that Python code can add
179 * attributes to heap types, and we make extensive use of this ability.
180 */
181
182 extern void *newtype(PyTypeObject */*meta*/,
183 const PyTypeObject */*skel*/, const char */*name*/);
184 /* Make and return a new Python type object, of type META (typically
185 * `PyType_Type', but may be a subclass), filled in from the skeleton SKEL
186 * (null to inherit everything), and named NAME. The caller can mess with
187 * the type object further at this time: call `typeready' when it's set up
188 * properly.
189 */
190
191 extern void typeready(PyTypeObject *);
192 /* The type object is now ready to be used. */
193
194 extern PyTypeObject *inittype(PyTypeObject */*skel*/,
195 PyTypeObject */*meta*/);
196 /* All-in-one function to construct a working type from a type skeleton
197 * SKEL, with metaclass META. The caller is expected to have filled in the
198 * direct superclass in SKEL->tp_base.
199 */
200
201 /* Alias for built-in types, to fit in with Pyke naming conventions. */
202 #define root_pytype 0
203 #define type_pytype &PyType_Type
204
205 #define INITTYPE_META(ty, base, meta) do { \
206 ty##_pytype_skel.tp_base = base##_pytype; \
207 ty##_pytype = inittype(&ty##_pytype_skel, meta##_pytype); \
208 } while (0)
209 #define INITTYPE(ty, base) INITTYPE_META(ty, base, type)
210 /* Macros to initialize a type from its skeleton. */
211
212 /* Convenience wrappers for filling in `PyMethodDef' tables, following
213 * Pyke naming convention. Define `METHNAME' locally as
214 *
215 * #define METHNAME(name) foometh_##func
216 *
217 * around the method table.
218 */
219 #define METH(func, doc) \
220 { #func, METHNAME(func), METH_VARARGS, doc },
221 #define KWMETH(func, doc) \
222 { #func, (PyCFunction)METHNAME(func), \
223 METH_VARARGS | METH_KEYWORDS, doc },
224
225 /* Convenience wrappers for filling in `PyGetSetDef' tables, following Pyke
226 * naming convention. Define `GETSETNAME' locally as
227 *
228 * #define GETSETNAME(op, name) foo##op##_##func
229 *
230 * around the get/set table.
231 */
232 #define GET(func, doc) \
233 { #func, GETSETNAME(get, func), 0, doc },
234 #define GETSET(func, doc) \
235 { #func, GETSETNAME(get, func), GETSETNAME(set, func), doc },
236
237 /* Convenience wrapper for filling in `PyMemberDef' tables. Define
238 * `MEMBERSTRUCT' locally as
239 *
240 * #define MEMBERSTRUCT foo_pyobj
241 *
242 * around the member table.
243 */
244 #define MEMBER(name, ty, f, doc) \
245 { #name, ty, offsetof(MEMBERSTRUCT, name), f, doc },
246
247 /*----- Populating modules ------------------------------------------------*/
248
249 extern PyObject *modname;
250 /* The overall module name. Set this with `PyString_FromString'. */
251
252 extern PyObject *home_module;
253 /* The overall module object. */
254
255 extern PyObject *mkexc(PyObject */*mod*/, PyObject */*base*/,
256 const char */*name*/, PyMethodDef */*methods*/);
257 /* Make and return an exception class called NAME, which will end up in
258 * module MOD (though it is not added at this time). The new class is a
259 * subclass of BASE. Attach the METHODS to it.
260 */
261
262 #define INSERT(name, ob) do { \
263 PyObject *_o = (PyObject *)(ob); \
264 Py_INCREF(_o); \
265 PyModule_AddObject(mod, name, _o); \
266 } while (0)
267 /* Insert a Python object OB into the module `mod' under the given NAME. */
268
269 /* Numeric constants. */
270 struct nameval { const char *name; unsigned f; unsigned long value; };
271 #define CF_SIGNED 1u
272 extern void setconstants(PyObject *, const struct nameval *);
273
274 #define INSEXC(name, var, base, meth) \
275 INSERT(name, var = mkexc(mod, base, name, meth))
276 /* Insert an exception class into the module `mod'; other arguments are as
277 * for `mkexc'.
278 */
279
280 /*----- Submodules --------------------------------------------------------*
281 *
282 * It's useful to split the Python module up into multiple source files, and
283 * have each one contribute its definitions into the main module.
284 *
285 * Define a list-macro `MODULES' in the master header file naming the
286 * submodules to be processed, and run
287 *
288 * MODULES(DECLARE_MODINIT)
289 *
290 * to declare the interface functions.
291 *
292 * Each submodule FOO defines two functions: `FOO_pyinit' initializes types
293 * (see `INITTYPE' above) and accumulates methods (`addmethods' below), while
294 * `FOO_pyinsert' populates the module with additional definitions
295 * (especially types, though also constants).
296 *
297 * The top-level module initialization should call `INIT_MODULES' before
298 * creating the Python module, and `INSERT_MODULES' afterwards to make
299 * everything work.
300 */
301
302 extern void addmethods(const PyMethodDef *);
303 extern PyMethodDef *donemethods(void);
304 /* Accumulate method-table fragments, and return the combined table of all
305 * of the fragments.
306 */
307
308 #define DECLARE_MODINIT(m) \
309 extern void m##_pyinit(void); \
310 extern void m##_pyinsert(PyObject *);
311 /* Declare submodule interface functions. */
312
313 #define DOMODINIT(m) m##_pyinit();
314 #define DOMODINSERT(m) m##_pyinsert(mod);
315 #define INIT_MODULES do { MODULES(DOMODINIT) } while (0)
316 #define INSERT_MODULES do { MODULES(DOMODINSERT) } while (0)
317 /* Top-level dispatch to the various submodules. */
318
319 /*----- Generic mapping support -------------------------------------------*/
320
321 /* Mapping methods. */
322 #define GMAP_METH(func, doc) { #func, gmapmeth_##func, METH_VARARGS, doc },
323 #define GMAP_KWMETH(func, doc) \
324 { #func, (PyCFunction)gmapmeth_##func, METH_VARARGS|METH_KEYWORDS, doc },
325 #define GMAP_METHDECL(func, doc) \
326 extern PyObject *gmapmeth_##func(PyObject *, PyObject *);
327 #define GMAP_KWMETHDECL(func, doc) \
328 extern PyObject *gmapmeth_##func(PyObject *, PyObject *, PyObject *);
329
330 #define GMAP_DOROMETHODS(METH, KWMETH) \
331 METH (has_key, "D.has_key(KEY) -> BOOL") \
332 METH (keys, "D.keys() -> LIST") \
333 METH (values, "D.values() -> LIST") \
334 METH (items, "D.items() -> LIST") \
335 METH (iterkeys, "D.iterkeys() -> ITER") \
336 METH (itervalues, "D.itervalues() -> ITER") \
337 METH (iteritems, "D.iteritems() -> ITER") \
338 KWMETH(get, "D.get(KEY, [default = None]) -> VALUE")
339
340 #define GMAP_DOMETHODS(METH, KWMETH) \
341 GMAP_DOROMETHODS(METH, KWMETH) \
342 METH (clear, "D.clear()") \
343 KWMETH(setdefault, "D.setdefault(K, [default = None]) -> VALUE") \
344 KWMETH(pop, "D.pop(KEY, [default = <error>]) -> VALUE") \
345 METH (popitem, "D.popitem() -> (KEY, VALUE)") \
346 METH (update, "D.update(MAP)")
347
348 GMAP_DOMETHODS(GMAP_METHDECL, GMAP_KWMETHDECL)
349 #define GMAP_ROMETHODS GMAP_DOROMETHODS(GMAP_METH, GMAP_KWMETH)
350 #define GMAP_METHODS GMAP_DOMETHODS(GMAP_METH, GMAP_KWMETH)
351
352 /* Mapping protocol implementation. */
353 extern Py_ssize_t gmap_pysize(PyObject *); /* for `mp_length' */
354 extern PySequenceMethods gmap_pysequence; /* for `tp_as_sequence' */
355 extern PyMethodDef gmap_pymethods[]; /* all the standard methods */
356
357 /*----- That's all, folks -------------------------------------------------*/
358
359 #ifdef __cplusplus
360 }
361 #endif
362
363 #endif