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 /*----- Python version compatibility hacks --------------------------------*/
  66
  67 /* The handy `Py_TYPE' and `Py_SIZE' macros turned up in 2.6.  Define them if
  68  * they're not already here.
  69  */
  70 #ifndef Py_TYPE
  71 #  define Py_TYPE(obj) (((PyObject *)(obj))->ob_type)
  72 #endif
  73 #ifndef Py_SIZE
  74 #  define Py_SIZE(obj) (((PyVarObject *)(obj))->ob_size)
  75 #endif
  76
  77 /*----- Utilities for returning values and exceptions ---------------------*/
  78
  79 /* Returning values. */
  80 #define RETURN_OBJ(obj) do { Py_INCREF(obj); return (obj); } while (0)
  81 #define RETURN_NONE RETURN_OBJ(Py_None)
  82 #define RETURN_NOTIMPL RETURN_OBJ(Py_NotImplemented)
  83 #define RETURN_TRUE RETURN_OBJ(Py_True)
  84 #define RETURN_FALSE RETURN_OBJ(Py_False)
  85 #define RETURN_ME RETURN_OBJ(me)
  86
  87 /* Returning exceptions.  (Note that `KeyError' is `MAPERR' here, because
  88  * Catacomb has its own kind of `KeyError'.)
  89  */
  90 #define EXCERR(exc, str) do {                                           \
  91   PyErr_SetString(exc, str);                                            \
  92   goto end;                                                             \
  93 } while (0)
  94 #define VALERR(str) EXCERR(PyExc_ValueError, str)
  95 #define OVFERR(str) EXCERR(PyExc_OverflowError, str)
  96 #define TYERR(str) EXCERR(PyExc_TypeError, str)
  97 #define IXERR(str) EXCERR(PyExc_IndexError, str)
  98 #define ZDIVERR(str) EXCERR(PyExc_ZeroDivisionError, str)
  99 #define SYSERR(str) EXCERR(PyExc_SystemError, str)
 100 #define NIERR(str) EXCERR(PyExc_NotImplementedError, str)
 101 #define MAPERR(idx) do {                                                \
 102   PyErr_SetObject(PyExc_KeyError, idx);                                 \
 103   goto end;                                                             \
 104 } while (0)
 105 #define OSERR(name) do {                                                \
 106   PyErr_SetFromErrnoWithFilename(PyExc_OSError, name);                  \
 107   goto end;                                                             \
 108 } while (0)
 109
 110 /* Saving and restoring exceptions. */
 111 struct excinfo { PyObject *ty, *val, *tb; };
 112 #define EXCINFO_INIT { 0, 0, 0 }
 113 #define INIT_EXCINFO(exc) do {                                          \
 114   struct excinfo *_exc = (exc); _exc->ty = _exc->val = _exc->tb = 0;    \
 115 } while (0)
 116 #define RELEASE_EXCINFO(exc) do {                                       \
 117   struct excinfo *_exc = (exc);                                         \
 118   Py_XDECREF(_exc->ty);  _exc->ty  = 0;                                 \
 119   Py_XDECREF(_exc->val); _exc->val = 0;                                 \
 120   Py_XDECREF(_exc->tb);  _exc->tb  = 0;                                 \
 121 } while (0)
 122 #define STASH_EXCINFO(exc) do {                                         \
 123   struct excinfo *_exc = (exc);                                         \
 124   PyErr_Fetch(&_exc->ty, &_exc->val, &_exc->tb);                        \
 125   PyErr_NormalizeException(&_exc->ty, &_exc->val, &_exc->tb);           \
 126 } while (0)
 127 #define RESTORE_EXCINFO(exc) do {                                       \
 128   struct excinfo *_exc = (exc);                                         \
 129   PyErr_Restore(_exc->ty, _exc->val, _exc->tb);                         \
 130   _exc->ty = _exc->val = _exc->tb = 0;                                  \
 131 } while (0)
 132 extern void report_lost_exception(struct excinfo *, const char *, ...);
 133 extern void report_lost_exception_v(struct excinfo *, const char *, va_list);
 134 extern void stash_exception(struct excinfo *, const char *, ...);
 135 extern void restore_exception(struct excinfo *, const char *, ...);
 136
 137 /*----- Conversions -------------------------------------------------------*/
 138
 139 /* Define an input conversion (`O&') function: check that the object has
 140  * Python type TY, and extract a C pointer to CTY by calling EXT on the
 141  * object (which may well be a macro).
 142  */
 143 #define CONVFUNC(ty, cty, ext)                                          \
 144   int conv##ty(PyObject *o, void *p)                                    \
 145   {                                                                     \
 146     if (!PyObject_TypeCheck(o, ty##_pytype))                            \
 147       TYERR("wanted a " #ty);                                           \
 148     *(cty *)p = ext(o);                                                 \
 149     return (1);                                                         \
 150   end:                                                                  \
 151     return (0);                                                         \
 152   }
 153
 154 /* Input conversion functions for standard kinds of objects, with overflow
 155  * checking where applicable.
 156  */
 157 extern int convulong(PyObject *, void *); /* unsigned long */
 158 extern int convuint(PyObject *, void *); /* unsigned int */
 159 extern int convszt(PyObject *, void *); /* size_t */
 160 extern int convbool(PyObject *, void *); /* bool */
 161
 162 /* Output conversions. */
 163 extern PyObject *getbool(int);          /* bool */
 164 extern PyObject *getulong(unsigned long); /* any kind of unsigned integer */
 165
 166 /*----- Miscellaneous utilities -------------------------------------------*/
 167
 168 #define FREEOBJ(obj) (Py_TYPE(obj)->tp_free((PyObject *)(obj)))
 169   /* Actually free OBJ, e.g., in a deallocation function. */
 170
 171 extern PyObject *abstract_pynew(PyTypeObject *, PyObject *, PyObject *);
 172   /* A `tp_new' function which refuses to make the object. */
 173
 174 #ifndef CONVERT_CAREFULLY
 175 #  define CONVERT_CAREFULLY(newty, expty, obj)                          \
 176      (!sizeof(*(expty *)0 = (obj)) + (/*unconst*/ newty)(obj))
 177   /* Convert OBJ to the type NEWTY, having previously checked that it is
 178    * convertible to the expected type EXPTY.
 179    *
 180    * Because of the way we set up types, we can make many kinds of tables be
 181    * `const' which can't usually be so (because Python will want to fiddle
 182    * with their reference counts); and, besides, Python's internals are
 183    * generally quite bad at being `const'-correct about tables.  One frequent
 184    * application of this macro, then, is in removing `const' from a type
 185    * without sacrificing all type safety.  The other common use is in
 186    * checking that method function types match up with the signatures
 187    * expected in their method definitions.
 188    */
 189 #endif
 190
 191 #define KWLIST CONVERT_CAREFULLY(char **, const char *const *, kwlist)
 192   /* Strip `const' qualifiers from the keyword list `kwlist'.  Useful when
 193    * calling `PyArg_ParseTupleAndKeywords', which isn't `const'-correct.
 194    */
 195
 196 /*----- Type definitions --------------------------------------------------*
 197  *
 198  * Pyke types are defined in a rather unusual way.
 199  *
 200  * The main code defines a `type skeleton' of type `PyTypeObject',
 201  * conventionally named `TY_pytype_skel'.  Unlike typical Python type
 202  * definitions in extensions, this can (and should) be read-only.  Also,
 203  * there's no point in setting the `tp_base' pointer here, because the actual
 204  * runtime base type object won't, in general, be known at compile time.
 205  * Instead, the type skeletons are converted into Python `heap types' by the
 206  * `INITTYPE' macro.  The main difference is that Python code can add
 207  * attributes to heap types, and we make extensive use of this ability.
 208  */
 209
 210 extern void *newtype(PyTypeObject */*meta*/,
 211                      const PyTypeObject */*skel*/, const char */*name*/);
 212   /* Make and return a new Python type object, of type META (typically
 213    * `PyType_Type', but may be a subclass), filled in from the skeleton SKEL
 214    * (null to inherit everything), and named NAME.  The caller can mess with
 215    * the type object further at this time: call `typeready' when it's set up
 216    * properly.
 217    */
 218
 219 extern void typeready(PyTypeObject *);
 220   /* The type object is now ready to be used. */
 221
 222 extern PyTypeObject *inittype(const PyTypeObject */*skel*/,
 223                               PyTypeObject */*base*/,
 224                               PyTypeObject */*meta*/);
 225   /* All-in-one function to construct a working type from a type skeleton
 226    * SKEL, with known base type BASE (null for `object') and metaclass.
 227    */
 228
 229 /* Alias for built-in types, to fit in with Pyke naming conventions. */
 230 #define root_pytype 0
 231 #define type_pytype &PyType_Type
 232
 233 #define INITTYPE_META(ty, base, meta) do {                              \
 234   ty##_pytype = inittype(&ty##_pytype_skel, base##_pytype, meta##_pytype); \
 235 } while (0)
 236 #define INITTYPE(ty, base) INITTYPE_META(ty, base, type)
 237   /* Macros to initialize a type from its skeleton. */
 238
 239 /* Macros for filling in `PyMethodDef' tables, ensuring that functions have
 240  * the expected signatures.
 241  */
 242 #define STD_METHOD(decor, func, flags, doc)                             \
 243   { #func, decor(func), METH_VARARGS | flags, doc },
 244 #define KEYWORD_METHOD(decor, func, flags, doc)                         \
 245   { #func,                                                              \
 246     CONVERT_CAREFULLY(PyCFunction, PyCFunctionWithKeywords, decor(func)), \
 247     METH_VARARGS | METH_KEYWORDS | flags,                               \
 248     doc },
 249 #define NOARG_METHOD(decor, func, flags, doc)                           \
 250   { #func,                                                              \
 251     CONVERT_CAREFULLY(PyCFunction, PyNoArgsFunction, decor(func)),      \
 252     METH_NOARGS | flags,                                                \
 253     doc },
 254
 255 /* Convenience wrappers for filling in `PyMethodDef' tables, following
 256  * Pyke naming convention.  Define `METHNAME' locally as
 257  *
 258  *      #define METHNAME(name) foometh_##func
 259  *
 260  * around the method table.
 261  */
 262 #define METH(func, doc) STD_METHOD(METHNAME, func, 0, doc)
 263 #define KWMETH(func, doc) KEYWORD_METHOD(METHNAME, func, 0, doc)
 264 #define NAMETH(func, doc) NOARG_METHOD(METHNAME, func, 0, doc)
 265 #define CMTH(func, doc) STD_METHOD(METHNAME, func, METH_CLASS, doc)
 266 #define KWCMTH(func, doc) KEYWORD_METHOD(METHNAME, func, METH_CLASS, doc)
 267 #define NACMTH(func, doc) NOARG_METHOD(METHNAME, func, METH_CLASS, doc)
 268 #define SMTH(func, doc) STD_METHOD(METHNAME, func, METH_STATIC, doc)
 269 #define KWSMTH(func, doc) KEYWORD_METHOD(METHNAME, func, METH_STATIC, doc)
 270 #define NASMTH(func, doc) NOARG_METHOD(METHNAME, func, METH_STATIC, doc)
 271
 272 /* Convenience wrappers for filling in `PyGetSetDef' tables, following Pyke
 273  * naming convention.  Define `GETSETNAME' locally as
 274  *
 275  *      #define GETSETNAME(op, name) foo##op##_##func
 276  *
 277  * around the get/set table.
 278  */
 279 #define GET(func, doc)                                                  \
 280   { #func, GETSETNAME(get, func), 0, doc },
 281 #define GETSET(func, doc)                                               \
 282   { #func, GETSETNAME(get, func), GETSETNAME(set, func), doc },
 283
 284 /* Convenience wrappers for filling in `PyMemberDef' tables.  Define
 285  * `MEMBERSTRUCT' locally as
 286  *
 287  *      #define MEMBERSTRUCT foo_pyobj
 288  *
 289  * around the member table.
 290  */
 291 #define MEMRNM(name, ty, mem, f, doc)                                   \
 292   { #name, ty, offsetof(MEMBERSTRUCT, mem), f, doc },
 293 #define MEMBER(name, ty, f, doc) MEMRNM(name, ty, name, f, doc)
 294
 295 /* Wrappers for filling in pointers in a `PyTypeObject' structure, (a)
 296  * following Pyke naming convention, and (b) stripping `const' from the types
 297  * without losing type safety.
 298  */
 299 #define UNCONST_TYPE_SLOT(type, suffix, op, ty)                         \
 300   CONVERT_CAREFULLY(type *, const type *, op ty##_py##suffix)
 301 #define PYGETSET(ty) UNCONST_TYPE_SLOT(PyGetSetDef, getset, NOTHING, ty)
 302 #define PYMETHODS(ty) UNCONST_TYPE_SLOT(PyMethodDef, methods, NOTHING, ty)
 303 #define PYMEMBERS(ty) UNCONST_TYPE_SLOT(PyMemberDef, members, NOTHING, ty)
 304 #define PYNUMBER(ty) UNCONST_TYPE_SLOT(PyNumberMethods, number, &, ty)
 305 #define PYSEQUENCE(ty) UNCONST_TYPE_SLOT(PySequenceMethods, sequence, &, ty)
 306 #define PYMAPPING(ty) UNCONST_TYPE_SLOT(PyMappingMethods, mapping, &, ty)
 307 #define PYBUFFER(ty) UNCONST_TYPE_SLOT(PyBufferProcs, buffer, &, ty)
 308
 309 /*----- Populating modules ------------------------------------------------*/
 310
 311 extern PyObject *modname;
 312   /* The overall module name.  Set this with `PyString_FromString'. */
 313
 314 extern PyObject *home_module;
 315   /* The overall module object. */
 316
 317 extern PyObject *mkexc(PyObject */*mod*/, PyObject */*base*/,
 318                        const char */*name*/, const PyMethodDef */*methods*/);
 319   /* Make and return an exception class called NAME, which will end up in
 320    * module MOD (though it is not added at this time).  The new class is a
 321    * subclass of BASE.  Attach the METHODS to it.
 322    */
 323
 324 #define INSERT(name, ob) do {                                           \
 325   PyObject *_o = (PyObject *)(ob);                                      \
 326   Py_INCREF(_o);                                                        \
 327   PyModule_AddObject(mod, name, _o);                                    \
 328 } while (0)
 329   /* Insert a Python object OB into the module `mod' under the given NAME. */
 330
 331 /* Numeric constants. */
 332 struct nameval { const char *name; unsigned f; unsigned long value; };
 333 #define CF_SIGNED 1u
 334 extern void setconstants(PyObject *, const struct nameval *);
 335 #define CONST(x) { #x, (x) >= 0 ? 0 : CF_SIGNED, x }
 336 #define CONSTFLAG(f, x) { #x, f, x }
 337
 338 #define INSEXC(name, var, base, meth)                                   \
 339   INSERT(name, var = mkexc(mod, base, name, meth))
 340   /* Insert an exception class into the module `mod'; other arguments are as
 341    * for `mkexc'.
 342    */
 343
 344 /*----- Submodules --------------------------------------------------------*
 345  *
 346  * It's useful to split the Python module up into multiple source files, and
 347  * have each one contribute its definitions into the main module.
 348  *
 349  * Define a list-macro `MODULES' in the master header file naming the
 350  * submodules to be processed, and run
 351  *
 352  *      MODULES(DECLARE_MODINIT)
 353  *
 354  * to declare the interface functions.
 355  *
 356  * Each submodule FOO defines two functions: `FOO_pyinit' initializes types
 357  * (see `INITTYPE' above) and accumulates methods (`addmethods' below), while
 358  * `FOO_pyinsert' populates the module with additional definitions
 359  * (especially types, though also constants).
 360  *
 361  * The top-level module initialization should call `INIT_MODULES' before
 362  * creating the Python module, and `INSERT_MODULES' afterwards to make
 363  * everything work.
 364  */
 365
 366 extern void addmethods(const PyMethodDef *);
 367 extern PyMethodDef *donemethods(void);
 368   /* Accumulate method-table fragments, and return the combined table of all
 369    * of the fragments.
 370    */
 371
 372 #define DECLARE_MODINIT(m)                                              \
 373   extern void m##_pyinit(void);                                         \
 374   extern void m##_pyinsert(PyObject *);
 375   /* Declare submodule interface functions. */
 376
 377 #define DOMODINIT(m) m##_pyinit();
 378 #define DOMODINSERT(m) m##_pyinsert(mod);
 379 #define INIT_MODULES do { MODULES(DOMODINIT) } while (0)
 380 #define INSERT_MODULES do { MODULES(DOMODINSERT) } while (0)
 381   /* Top-level dispatch to the various submodules. */
 382
 383 /*----- Generic mapping support -------------------------------------------*/
 384
 385 /* Operations table.  ME is the mapping object throughout. */
 386 typedef struct gmap_ops {
 387   size_t isz;                           /* iterator size */
 388
 389   void *(*lookup)(PyObject *me, PyObject *key, unsigned *f);
 390     /* Lookup the KEY.  If it is found, return an entry pointer for it; if F
 391      * is not null, set *F nonzero.  Otherwise, if F is null, return a null
 392      * pointer (without setting a pending exception); if F is not null, then
 393      * set *F zero and return a fresh entry pointer.  Return null on a Python
 394      * exception (the caller will notice the difference.)
 395      */
 396
 397   void (*iter_init)(PyObject *me, void *i);
 398     /* Initialize an iterator at I. */
 399
 400   void *(*iter_next)(PyObject *me, void *i);
 401     /* Return an entry pointer for a different item, or null if all have been
 402      * visited.
 403      */
 404
 405   PyObject *(*entry_key)(PyObject *me, void *e);
 406     /* Return the key object for a mapping entry. */
 407
 408   PyObject *(*entry_value)(PyObject *me, void *e);
 409     /* Return the value object for a mapping entry. */
 410
 411   int (*set_entry)(PyObject *me, void *e, PyObject *val);
 412     /* Modify the entry by storing VAL in its place.  Return 0 on success,
 413      * or -1 on a Python error.
 414      */
 415
 416   int (*del_entry)(PyObject *me, void *e);
 417     /* Delete the entry.  (It may be necessary to delete a freshly allocated
 418      * entry, e.g., if `set_entry' failed.)  Return 0 on success, or -1 on a
 419      * Python error.
 420      */
 421 } gmap_ops;
 422
 423 /* The intrusion at the head of a mapping object. */
 424 #define GMAP_PYOBJ_HEAD                                                 \
 425   PyObject_HEAD                                                         \
 426   const gmap_ops *gmops;
 427
 428 typedef struct gmap_pyobj {
 429   GMAP_PYOBJ_HEAD
 430 } gmap_pyobj;
 431 #define GMAP_OPS(obj) (((gmap_pyobj *)(obj))->gmops)
 432   /* Discover the operations from a mapping object. */
 433
 434 /* Mapping methods. */
 435 #define GMAP_METMNAME(func) gmapmeth_##func
 436 #define GMAP_METH(func, doc) STD_METHOD(GMAP_METMNAME, func, 0, doc)
 437 #define GMAP_KWMETH(func, doc) KEYWORD_METHOD(GMAP_METMNAME, func, 0, doc)
 438 #define GMAP_NAMETH(func, doc) NOARG_METHOD(GMAP_METMNAME, func, 0, doc)
 439 #define GMAP_METHDECL(func, doc)                                        \
 440   extern PyObject *gmapmeth_##func(PyObject *, PyObject *);
 441 #define GMAP_KWMETHDECL(func, doc)                                      \
 442   extern PyObject *gmapmeth_##func(PyObject *, PyObject *, PyObject *);
 443 #define GMAP_NAMETHDECL(func, doc)                                      \
 444   extern PyObject *gmapmeth_##func(PyObject *);
 445
 446 #define GMAP_DOROMETHODS(METH, KWMETH, NAMETH)                          \
 447   METH  (has_key,       "D.has_key(KEY) -> BOOL")                       \
 448   NAMETH(keys,          "D.keys() -> LIST")                             \
 449   NAMETH(values,        "D.values() -> LIST")                           \
 450   NAMETH(items,         "D.items() -> LIST")                            \
 451   NAMETH(iterkeys,      "D.iterkeys() -> ITER")                         \
 452   NAMETH(itervalues,    "D.itervalues() -> ITER")                       \
 453   NAMETH(iteritems,     "D.iteritems() -> ITER")                        \
 454   KWMETH(get,           "D.get(KEY, [default = None]) -> VALUE")
 455
 456 #define GMAP_DOMETHODS(METH, KWMETH, NAMETH)                            \
 457   GMAP_DOROMETHODS(METH, KWMETH, NAMETH)                                \
 458   NAMETH(clear,         "D.clear()")                                    \
 459   KWMETH(setdefault,    "D.setdefault(K, [default = None]) -> VALUE")   \
 460   KWMETH(pop,           "D.pop(KEY, [default = <error>]) -> VALUE")     \
 461   NAMETH(popitem,       "D.popitem() -> (KEY, VALUE)")                  \
 462   KWMETH(update,        "D.update(MAP)")
 463
 464 GMAP_DOMETHODS(GMAP_METHDECL, GMAP_KWMETHDECL, GMAP_NAMETHDECL)
 465 #define GMAP_ROMETHODS GMAP_DOROMETHODS(GMAP_METH, GMAP_KWMETH, GMAP_NAMETH)
 466 #define GMAP_METHODS GMAP_DOMETHODS(GMAP_METH, GMAP_KWMETH, GMAP_NAMETH)
 467
 468 /* Mapping protocol implementation. */
 469 extern Py_ssize_t gmap_pysize(PyObject *); /* for `mp_length' */
 470 extern PyObject *gmap_pyiter(PyObject *); /* for `tp_iter' */
 471 extern PyObject *gmap_pylookup(PyObject *, PyObject *); /* for `mp_subscript' */
 472 extern int gmap_pystore(PyObject *, PyObject *, PyObject *); /* for `mp_ass_subscript' */
 473 extern int gmap_pyhaskey(PyObject *, PyObject *); /* for `sq_contains' */
 474 extern const PySequenceMethods gmap_pysequence; /* for `tp_as_sequence' */
 475 extern const PyMethodDef gmapro_pymethods[]; /* read-only methods */
 476 extern const PyMethodDef gmap_pymethods[]; /* all the standard methods */
 477
 478 /*----- That's all, folks -------------------------------------------------*/
 479
 480 #ifdef __cplusplus
 481   }
 482 #endif
 483
 484 #endif