mdw@git.distorted.org.uk Git - pyke/blob - 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 MAPERR(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 #ifndef CONVERT_CAREFULLY
 164 #  define CONVERT_CAREFULLY(newty, expty, obj)                          \
 165      (!sizeof(*(expty *)0 = (obj)) + (/*unconst*/ newty)(obj))
 166   /* Convert OBJ to the type NEWTY, having previously checked that it is
 167    * convertible to the expected type EXPTY.
 168    *
 169    * Because of the way we set up types, we can make many kinds of tables be
 170    * `const' which can't usually be so (because Python will want to fiddle
 171    * with their reference counts); and, besides, Python's internals are
 172    * generally quite bad at being `const'-correct about tables.  One frequent
 173    * application of this macro, then, is in removing `const' from a type
 174    * without sacrificing all type safety.  The other common use is in
 175    * checking that method function types match up with the signatures
 176    * expected in their method definitions.
 177    */
 178 #endif
 179
 180 #define KWLIST CONVERT_CAREFULLY(char **, const char *const *, kwlist)
 181   /* Strip `const' qualifiers from the keyword list `kwlist'.  Useful when
 182    * calling `PyArg_ParseTupleAndKeywords', which isn't `const'-correct.
 183    */
 184
 185 /*----- Type definitions --------------------------------------------------*
 186  *
 187  * Pyke types are defined in a rather unusual way.
 188  *
 189  * The main code defines a `type skeleton' of type `PyTypeObject',
 190  * conventionally named `TY_pytype_skel'.  Unlike typical Python type
 191  * definitions in extensions, this can (and should) be read-only.  Also,
 192  * there's no point in setting the `tp_base' pointer here, because the actual
 193  * runtime base type object won't, in general, be known at compile time.
 194  * Instead, the type skeletons are converted into Python `heap types' by the
 195  * `INITTYPE' macro.  The main difference is that Python code can add
 196  * attributes to heap types, and we make extensive use of this ability.
 197  */
 198
 199 extern void *newtype(PyTypeObject */*meta*/,
 200                      const PyTypeObject */*skel*/, const char */*name*/);
 201   /* Make and return a new Python type object, of type META (typically
 202    * `PyType_Type', but may be a subclass), filled in from the skeleton SKEL
 203    * (null to inherit everything), and named NAME.  The caller can mess with
 204    * the type object further at this time: call `typeready' when it's set up
 205    * properly.
 206    */
 207
 208 extern void typeready(PyTypeObject *);
 209   /* The type object is now ready to be used. */
 210
 211 extern PyTypeObject *inittype(const PyTypeObject */*skel*/,
 212                               PyTypeObject */*base*/,
 213                               PyTypeObject */*meta*/);
 214   /* All-in-one function to construct a working type from a type skeleton
 215    * SKEL, with known base type BASE (null for `object') and metaclass.
 216    */
 217
 218 /* Alias for built-in types, to fit in with Pyke naming conventions. */
 219 #define root_pytype 0
 220 #define type_pytype &PyType_Type
 221
 222 #define INITTYPE_META(ty, base, meta) do {                              \
 223   ty##_pytype = inittype(&ty##_pytype_skel, base##_pytype, meta##_pytype); \
 224 } while (0)
 225 #define INITTYPE(ty, base) INITTYPE_META(ty, base, type)
 226   /* Macros to initialize a type from its skeleton. */
 227
 228 /* Macros for filling in `PyMethodDef' tables, ensuring that functions have
 229  * the expected signatures.
 230  */
 231 #define STD_METHOD(decor, func, flags, doc)                             \
 232   { #func, decor(func), METH_VARARGS | flags, doc },
 233 #define KEYWORD_METHOD(decor, func, flags, doc)                         \
 234   { #func,                                                              \
 235     CONVERT_CAREFULLY(PyCFunction, PyCFunctionWithKeywords, decor(func)), \
 236     METH_VARARGS | METH_KEYWORDS | flags,                               \
 237     doc },
 238 #define NOARG_METHOD(decor, func, flags, doc)                           \
 239   { #func,                                                              \
 240     CONVERT_CAREFULLY(PyCFunction, PyNoArgsFunction, decor(func)),      \
 241     METH_NOARGS | flags,                                                \
 242     doc },
 243
 244 /* Convenience wrappers for filling in `PyMethodDef' tables, following
 245  * Pyke naming convention.  Define `METHNAME' locally as
 246  *
 247  *      #define METHNAME(name) foometh_##func
 248  *
 249  * around the method table.
 250  */
 251 #define METH(func, doc) STD_METHOD(METHNAME, func, 0, doc)
 252 #define KWMETH(func, doc) KEYWORD_METHOD(METHNAME, func, 0, doc)
 253 #define NAMETH(func, doc) NOARG_METHOD(METHNAME, func, 0, doc)
 254 #define CMTH(func, doc) STD_METHOD(METHNAME, func, METH_CLASS, doc)
 255 #define KWCMTH(func, doc) KEYWORD_METHOD(METHNAME, func, METH_CLASS, doc)
 256 #define NACMTH(func, doc) NOARG_METHOD(METHNAME, func, METH_CLASS, doc)
 257 #define SMTH(func, doc) STD_METHOD(METHNAME, func, METH_STATIC, doc)
 258 #define KWSMTH(func, doc) KEYWORD_METHOD(METHNAME, func, METH_STATIC, doc)
 259 #define NASMTH(func, doc) NOARG_METHOD(METHNAME, func, METH_STATIC, doc)
 260
 261 /* Convenience wrappers for filling in `PyGetSetDef' tables, following Pyke
 262  * naming convention.  Define `GETSETNAME' locally as
 263  *
 264  *      #define GETSETNAME(op, name) foo##op##_##func
 265  *
 266  * around the get/set table.
 267  */
 268 #define GET(func, doc)                                                  \
 269   { #func, GETSETNAME(get, func), 0, doc },
 270 #define GETSET(func, doc)                                               \
 271   { #func, GETSETNAME(get, func), GETSETNAME(set, func), doc },
 272
 273 /* Convenience wrappers for filling in `PyMemberDef' tables.  Define
 274  * `MEMBERSTRUCT' locally as
 275  *
 276  *      #define MEMBERSTRUCT foo_pyobj
 277  *
 278  * around the member table.
 279  */
 280 #define MEMRNM(name, ty, mem, f, doc)                                   \
 281   { #name, ty, offsetof(MEMBERSTRUCT, mem), f, doc },
 282 #define MEMBER(name, ty, f, doc) MEMRNM(name, ty, name, f, doc)
 283
 284 /* Wrappers for filling in pointers in a `PyTypeObject' structure, (a)
 285  * following Pyke naming convention, and (b) stripping `const' from the types
 286  * without losing type safety.
 287  */
 288 #define UNCONST_TYPE_SLOT(type, suffix, op, ty)                         \
 289   CONVERT_CAREFULLY(type *, const type *, op ty##_py##suffix)
 290 #define PYGETSET(ty) UNCONST_TYPE_SLOT(PyGetSetDef, getset, NOTHING, ty)
 291 #define PYMETHODS(ty) UNCONST_TYPE_SLOT(PyMethodDef, methods, NOTHING, ty)
 292 #define PYMEMBERS(ty) UNCONST_TYPE_SLOT(PyMemberDef, members, NOTHING, ty)
 293 #define PYNUMBER(ty) UNCONST_TYPE_SLOT(PyNumberMethods, number, &, ty)
 294 #define PYSEQUENCE(ty) UNCONST_TYPE_SLOT(PySequenceMethods, sequence, &, ty)
 295 #define PYMAPPING(ty) UNCONST_TYPE_SLOT(PyMappingMethods, mapping, &, ty)
 296 #define PYBUFFER(ty) UNCONST_TYPE_SLOT(PyBufferProcs, buffer, &, ty)
 297
 298 /*----- Populating modules ------------------------------------------------*/
 299
 300 extern PyObject *modname;
 301   /* The overall module name.  Set this with `PyString_FromString'. */
 302
 303 extern PyObject *home_module;
 304   /* The overall module object. */
 305
 306 extern PyObject *mkexc(PyObject */*mod*/, PyObject */*base*/,
 307                        const char */*name*/, const PyMethodDef */*methods*/);
 308   /* Make and return an exception class called NAME, which will end up in
 309    * module MOD (though it is not added at this time).  The new class is a
 310    * subclass of BASE.  Attach the METHODS to it.
 311    */
 312
 313 #define INSERT(name, ob) do {                                           \
 314   PyObject *_o = (PyObject *)(ob);                                      \
 315   Py_INCREF(_o);                                                        \
 316   PyModule_AddObject(mod, name, _o);                                    \
 317 } while (0)
 318   /* Insert a Python object OB into the module `mod' under the given NAME. */
 319
 320 /* Numeric constants. */
 321 struct nameval { const char *name; unsigned f; unsigned long value; };
 322 #define CF_SIGNED 1u
 323 extern void setconstants(PyObject *, const struct nameval *);
 324 #define CONST(x) { #x, (x) >= 0 ? 0 : CF_SIGNED, x }
 325 #define CONSTFLAG(f, x) { #x, f, x }
 326
 327 #define INSEXC(name, var, base, meth)                                   \
 328   INSERT(name, var = mkexc(mod, base, name, meth))
 329   /* Insert an exception class into the module `mod'; other arguments are as
 330    * for `mkexc'.
 331    */
 332
 333 /*----- Submodules --------------------------------------------------------*
 334  *
 335  * It's useful to split the Python module up into multiple source files, and
 336  * have each one contribute its definitions into the main module.
 337  *
 338  * Define a list-macro `MODULES' in the master header file naming the
 339  * submodules to be processed, and run
 340  *
 341  *      MODULES(DECLARE_MODINIT)
 342  *
 343  * to declare the interface functions.
 344  *
 345  * Each submodule FOO defines two functions: `FOO_pyinit' initializes types
 346  * (see `INITTYPE' above) and accumulates methods (`addmethods' below), while
 347  * `FOO_pyinsert' populates the module with additional definitions
 348  * (especially types, though also constants).
 349  *
 350  * The top-level module initialization should call `INIT_MODULES' before
 351  * creating the Python module, and `INSERT_MODULES' afterwards to make
 352  * everything work.
 353  */
 354
 355 extern void addmethods(const PyMethodDef *);
 356 extern PyMethodDef *donemethods(void);
 357   /* Accumulate method-table fragments, and return the combined table of all
 358    * of the fragments.
 359    */
 360
 361 #define DECLARE_MODINIT(m)                                              \
 362   extern void m##_pyinit(void);                                         \
 363   extern void m##_pyinsert(PyObject *);
 364   /* Declare submodule interface functions. */
 365
 366 #define DOMODINIT(m) m##_pyinit();
 367 #define DOMODINSERT(m) m##_pyinsert(mod);
 368 #define INIT_MODULES do { MODULES(DOMODINIT) } while (0)
 369 #define INSERT_MODULES do { MODULES(DOMODINSERT) } while (0)
 370   /* Top-level dispatch to the various submodules. */
 371
 372 /*----- Generic mapping support -------------------------------------------*/
 373
 374 /* Operations table.  ME is the mapping object throughout. */
 375 typedef struct gmap_ops {
 376   size_t isz;                           /* iterator size */
 377
 378   void *(*lookup)(PyObject *me, PyObject *key, unsigned *f);
 379     /* Lookup the KEY.  If it is found, return an entry pointer for it; if F
 380      * is not null, set *F nonzero.  Otherwise, if F is null, return a null
 381      * pointer (without setting a pending exception); if F is not null, then
 382      * set *F zero and return a fresh entry pointer.  Return null on a Python
 383      * exception (the caller will notice the difference.)
 384      */
 385
 386   void (*iter_init)(PyObject *me, void *i);
 387     /* Initialize an iterator at I. */
 388
 389   void *(*iter_next)(PyObject *me, void *i);
 390     /* Return an entry pointer for a different item, or null if all have been
 391      * visited.
 392      */
 393
 394   PyObject *(*entry_key)(PyObject *me, void *e);
 395     /* Return the key object for a mapping entry. */
 396
 397   PyObject *(*entry_value)(PyObject *me, void *e);
 398     /* Return the value object for a mapping entry. */
 399
 400   int (*set_entry)(PyObject *me, void *e, PyObject *val);
 401     /* Modify the entry by storing VAL in its place.  Return 0 on success,
 402      * or -1 on a Python error.
 403      */
 404
 405   int (*del_entry)(PyObject *me, void *e);
 406     /* Delete the entry.  (It may be necessary to delete a freshly allocated
 407      * entry, e.g., if `set_entry' failed.)  Return 0 on success, or -1 on a
 408      * Python error.
 409      */
 410 } gmap_ops;
 411
 412 /* The intrusion at the head of a mapping object. */
 413 #define GMAP_PYOBJ_HEAD                                                 \
 414   PyObject_HEAD                                                         \
 415   const gmap_ops *gmops;
 416
 417 typedef struct gmap_pyobj {
 418   GMAP_PYOBJ_HEAD
 419 } gmap_pyobj;
 420 #define GMAP_OPS(obj) (((gmap_pyobj *)(obj))->gmops)
 421   /* Discover the operations from a mapping object. */
 422
 423 /* Mapping methods. */
 424 #define GMAP_METMNAME(func) gmapmeth_##func
 425 #define GMAP_METH(func, doc) STD_METHOD(GMAP_METMNAME, func, 0, doc)
 426 #define GMAP_KWMETH(func, doc) KEYWORD_METHOD(GMAP_METMNAME, func, 0, doc)
 427 #define GMAP_NAMETH(func, doc) NOARG_METHOD(GMAP_METMNAME, func, 0, doc)
 428 #define GMAP_METHDECL(func, doc)                                        \
 429   extern PyObject *gmapmeth_##func(PyObject *, PyObject *);
 430 #define GMAP_KWMETHDECL(func, doc)                                      \
 431   extern PyObject *gmapmeth_##func(PyObject *, PyObject *, PyObject *);
 432 #define GMAP_NAMETHDECL(func, doc)                                      \
 433   extern PyObject *gmapmeth_##func(PyObject *);
 434
 435 #define GMAP_DOROMETHODS(METH, KWMETH, NAMETH)                          \
 436   METH  (has_key,       "D.has_key(KEY) -> BOOL")                       \
 437   NAMETH(keys,          "D.keys() -> LIST")                             \
 438   NAMETH(values,        "D.values() -> LIST")                           \
 439   NAMETH(items,         "D.items() -> LIST")                            \
 440   NAMETH(iterkeys,      "D.iterkeys() -> ITER")                         \
 441   NAMETH(itervalues,    "D.itervalues() -> ITER")                       \
 442   NAMETH(iteritems,     "D.iteritems() -> ITER")                        \
 443   KWMETH(get,           "D.get(KEY, [default = None]) -> VALUE")
 444
 445 #define GMAP_DOMETHODS(METH, KWMETH, NAMETH)                            \
 446   GMAP_DOROMETHODS(METH, KWMETH, NAMETH)                                \
 447   NAMETH(clear,         "D.clear()")                                    \
 448   KWMETH(setdefault,    "D.setdefault(K, [default = None]) -> VALUE")   \
 449   KWMETH(pop,           "D.pop(KEY, [default = <error>]) -> VALUE")     \
 450   NAMETH(popitem,       "D.popitem() -> (KEY, VALUE)")                  \
 451   KWMETH(update,        "D.update(MAP)")
 452
 453 GMAP_DOMETHODS(GMAP_METHDECL, GMAP_KWMETHDECL, GMAP_NAMETHDECL)
 454 #define GMAP_ROMETHODS GMAP_DOROMETHODS(GMAP_METH, GMAP_KWMETH, GMAP_NAMETH)
 455 #define GMAP_METHODS GMAP_DOMETHODS(GMAP_METH, GMAP_KWMETH, GMAP_NAMETH)
 456
 457 /* Mapping protocol implementation. */
 458 extern Py_ssize_t gmap_pysize(PyObject *); /* for `mp_length' */
 459 extern PyObject *gmap_pyiter(PyObject *); /* for `tp_iter' */
 460 extern PyObject *gmap_pylookup(PyObject *, PyObject *); /* for `mp_subscript' */
 461 extern int gmap_pystore(PyObject *, PyObject *, PyObject *); /* for `mp_ass_subscript' */
 462 extern int gmap_pyhaskey(PyObject *, PyObject *); /* for `sq_contains' */
 463 extern const PySequenceMethods gmap_pysequence; /* for `tp_as_sequence' */
 464 extern const PyMethodDef gmapro_pymethods[]; /* read-only methods */
 465 extern const PyMethodDef gmap_pymethods[]; /* all the standard methods */
 466
 467 /*----- That's all, folks -------------------------------------------------*/
 468
 469 #ifdef __cplusplus
 470   }
 471 #endif
 472
 473 #endif