Mercurial > repos > yating-l > jbrowsearchivecreator
comparison test/include/python2.7/object.h @ 3:7d1a9a91b989 draft
planemo upload for repository https://github.com/Yating-L/jbrowse-archive-creator.git commit d583ac16a6c6942730ea536eb59cc37941816030-dirty
| author | yating-l |
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| date | Thu, 18 May 2017 18:37:28 -0400 |
| parents | |
| children |
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| 2:3e2160197902 | 3:7d1a9a91b989 |
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| 1 #ifndef Py_OBJECT_H | |
| 2 #define Py_OBJECT_H | |
| 3 #ifdef __cplusplus | |
| 4 extern "C" { | |
| 5 #endif | |
| 6 | |
| 7 | |
| 8 /* Object and type object interface */ | |
| 9 | |
| 10 /* | |
| 11 Objects are structures allocated on the heap. Special rules apply to | |
| 12 the use of objects to ensure they are properly garbage-collected. | |
| 13 Objects are never allocated statically or on the stack; they must be | |
| 14 accessed through special macros and functions only. (Type objects are | |
| 15 exceptions to the first rule; the standard types are represented by | |
| 16 statically initialized type objects, although work on type/class unification | |
| 17 for Python 2.2 made it possible to have heap-allocated type objects too). | |
| 18 | |
| 19 An object has a 'reference count' that is increased or decreased when a | |
| 20 pointer to the object is copied or deleted; when the reference count | |
| 21 reaches zero there are no references to the object left and it can be | |
| 22 removed from the heap. | |
| 23 | |
| 24 An object has a 'type' that determines what it represents and what kind | |
| 25 of data it contains. An object's type is fixed when it is created. | |
| 26 Types themselves are represented as objects; an object contains a | |
| 27 pointer to the corresponding type object. The type itself has a type | |
| 28 pointer pointing to the object representing the type 'type', which | |
| 29 contains a pointer to itself!). | |
| 30 | |
| 31 Objects do not float around in memory; once allocated an object keeps | |
| 32 the same size and address. Objects that must hold variable-size data | |
| 33 can contain pointers to variable-size parts of the object. Not all | |
| 34 objects of the same type have the same size; but the size cannot change | |
| 35 after allocation. (These restrictions are made so a reference to an | |
| 36 object can be simply a pointer -- moving an object would require | |
| 37 updating all the pointers, and changing an object's size would require | |
| 38 moving it if there was another object right next to it.) | |
| 39 | |
| 40 Objects are always accessed through pointers of the type 'PyObject *'. | |
| 41 The type 'PyObject' is a structure that only contains the reference count | |
| 42 and the type pointer. The actual memory allocated for an object | |
| 43 contains other data that can only be accessed after casting the pointer | |
| 44 to a pointer to a longer structure type. This longer type must start | |
| 45 with the reference count and type fields; the macro PyObject_HEAD should be | |
| 46 used for this (to accommodate for future changes). The implementation | |
| 47 of a particular object type can cast the object pointer to the proper | |
| 48 type and back. | |
| 49 | |
| 50 A standard interface exists for objects that contain an array of items | |
| 51 whose size is determined when the object is allocated. | |
| 52 */ | |
| 53 | |
| 54 /* Py_DEBUG implies Py_TRACE_REFS. */ | |
| 55 #if defined(Py_DEBUG) && !defined(Py_TRACE_REFS) | |
| 56 #define Py_TRACE_REFS | |
| 57 #endif | |
| 58 | |
| 59 /* Py_TRACE_REFS implies Py_REF_DEBUG. */ | |
| 60 #if defined(Py_TRACE_REFS) && !defined(Py_REF_DEBUG) | |
| 61 #define Py_REF_DEBUG | |
| 62 #endif | |
| 63 | |
| 64 #ifdef Py_TRACE_REFS | |
| 65 /* Define pointers to support a doubly-linked list of all live heap objects. */ | |
| 66 #define _PyObject_HEAD_EXTRA \ | |
| 67 struct _object *_ob_next; \ | |
| 68 struct _object *_ob_prev; | |
| 69 | |
| 70 #define _PyObject_EXTRA_INIT 0, 0, | |
| 71 | |
| 72 #else | |
| 73 #define _PyObject_HEAD_EXTRA | |
| 74 #define _PyObject_EXTRA_INIT | |
| 75 #endif | |
| 76 | |
| 77 /* PyObject_HEAD defines the initial segment of every PyObject. */ | |
| 78 #define PyObject_HEAD \ | |
| 79 _PyObject_HEAD_EXTRA \ | |
| 80 Py_ssize_t ob_refcnt; \ | |
| 81 struct _typeobject *ob_type; | |
| 82 | |
| 83 #define PyObject_HEAD_INIT(type) \ | |
| 84 _PyObject_EXTRA_INIT \ | |
| 85 1, type, | |
| 86 | |
| 87 #define PyVarObject_HEAD_INIT(type, size) \ | |
| 88 PyObject_HEAD_INIT(type) size, | |
| 89 | |
| 90 /* PyObject_VAR_HEAD defines the initial segment of all variable-size | |
| 91 * container objects. These end with a declaration of an array with 1 | |
| 92 * element, but enough space is malloc'ed so that the array actually | |
| 93 * has room for ob_size elements. Note that ob_size is an element count, | |
| 94 * not necessarily a byte count. | |
| 95 */ | |
| 96 #define PyObject_VAR_HEAD \ | |
| 97 PyObject_HEAD \ | |
| 98 Py_ssize_t ob_size; /* Number of items in variable part */ | |
| 99 #define Py_INVALID_SIZE (Py_ssize_t)-1 | |
| 100 | |
| 101 /* Nothing is actually declared to be a PyObject, but every pointer to | |
| 102 * a Python object can be cast to a PyObject*. This is inheritance built | |
| 103 * by hand. Similarly every pointer to a variable-size Python object can, | |
| 104 * in addition, be cast to PyVarObject*. | |
| 105 */ | |
| 106 typedef struct _object { | |
| 107 PyObject_HEAD | |
| 108 } PyObject; | |
| 109 | |
| 110 typedef struct { | |
| 111 PyObject_VAR_HEAD | |
| 112 } PyVarObject; | |
| 113 | |
| 114 #define Py_REFCNT(ob) (((PyObject*)(ob))->ob_refcnt) | |
| 115 #define Py_TYPE(ob) (((PyObject*)(ob))->ob_type) | |
| 116 #define Py_SIZE(ob) (((PyVarObject*)(ob))->ob_size) | |
| 117 | |
| 118 /* | |
| 119 Type objects contain a string containing the type name (to help somewhat | |
| 120 in debugging), the allocation parameters (see PyObject_New() and | |
| 121 PyObject_NewVar()), | |
| 122 and methods for accessing objects of the type. Methods are optional, a | |
| 123 nil pointer meaning that particular kind of access is not available for | |
| 124 this type. The Py_DECREF() macro uses the tp_dealloc method without | |
| 125 checking for a nil pointer; it should always be implemented except if | |
| 126 the implementation can guarantee that the reference count will never | |
| 127 reach zero (e.g., for statically allocated type objects). | |
| 128 | |
| 129 NB: the methods for certain type groups are now contained in separate | |
| 130 method blocks. | |
| 131 */ | |
| 132 | |
| 133 typedef PyObject * (*unaryfunc)(PyObject *); | |
| 134 typedef PyObject * (*binaryfunc)(PyObject *, PyObject *); | |
| 135 typedef PyObject * (*ternaryfunc)(PyObject *, PyObject *, PyObject *); | |
| 136 typedef int (*inquiry)(PyObject *); | |
| 137 typedef Py_ssize_t (*lenfunc)(PyObject *); | |
| 138 typedef int (*coercion)(PyObject **, PyObject **); | |
| 139 typedef PyObject *(*intargfunc)(PyObject *, int) Py_DEPRECATED(2.5); | |
| 140 typedef PyObject *(*intintargfunc)(PyObject *, int, int) Py_DEPRECATED(2.5); | |
| 141 typedef PyObject *(*ssizeargfunc)(PyObject *, Py_ssize_t); | |
| 142 typedef PyObject *(*ssizessizeargfunc)(PyObject *, Py_ssize_t, Py_ssize_t); | |
| 143 typedef int(*intobjargproc)(PyObject *, int, PyObject *); | |
| 144 typedef int(*intintobjargproc)(PyObject *, int, int, PyObject *); | |
| 145 typedef int(*ssizeobjargproc)(PyObject *, Py_ssize_t, PyObject *); | |
| 146 typedef int(*ssizessizeobjargproc)(PyObject *, Py_ssize_t, Py_ssize_t, PyObject *); | |
| 147 typedef int(*objobjargproc)(PyObject *, PyObject *, PyObject *); | |
| 148 | |
| 149 | |
| 150 | |
| 151 /* int-based buffer interface */ | |
| 152 typedef int (*getreadbufferproc)(PyObject *, int, void **); | |
| 153 typedef int (*getwritebufferproc)(PyObject *, int, void **); | |
| 154 typedef int (*getsegcountproc)(PyObject *, int *); | |
| 155 typedef int (*getcharbufferproc)(PyObject *, int, char **); | |
| 156 /* ssize_t-based buffer interface */ | |
| 157 typedef Py_ssize_t (*readbufferproc)(PyObject *, Py_ssize_t, void **); | |
| 158 typedef Py_ssize_t (*writebufferproc)(PyObject *, Py_ssize_t, void **); | |
| 159 typedef Py_ssize_t (*segcountproc)(PyObject *, Py_ssize_t *); | |
| 160 typedef Py_ssize_t (*charbufferproc)(PyObject *, Py_ssize_t, char **); | |
| 161 | |
| 162 | |
| 163 /* Py3k buffer interface */ | |
| 164 typedef struct bufferinfo { | |
| 165 void *buf; | |
| 166 PyObject *obj; /* owned reference */ | |
| 167 Py_ssize_t len; | |
| 168 Py_ssize_t itemsize; /* This is Py_ssize_t so it can be | |
| 169 pointed to by strides in simple case.*/ | |
| 170 int readonly; | |
| 171 int ndim; | |
| 172 char *format; | |
| 173 Py_ssize_t *shape; | |
| 174 Py_ssize_t *strides; | |
| 175 Py_ssize_t *suboffsets; | |
| 176 Py_ssize_t smalltable[2]; /* static store for shape and strides of | |
| 177 mono-dimensional buffers. */ | |
| 178 void *internal; | |
| 179 } Py_buffer; | |
| 180 | |
| 181 typedef int (*getbufferproc)(PyObject *, Py_buffer *, int); | |
| 182 typedef void (*releasebufferproc)(PyObject *, Py_buffer *); | |
| 183 | |
| 184 /* Flags for getting buffers */ | |
| 185 #define PyBUF_SIMPLE 0 | |
| 186 #define PyBUF_WRITABLE 0x0001 | |
| 187 /* we used to include an E, backwards compatible alias */ | |
| 188 #define PyBUF_WRITEABLE PyBUF_WRITABLE | |
| 189 #define PyBUF_FORMAT 0x0004 | |
| 190 #define PyBUF_ND 0x0008 | |
| 191 #define PyBUF_STRIDES (0x0010 | PyBUF_ND) | |
| 192 #define PyBUF_C_CONTIGUOUS (0x0020 | PyBUF_STRIDES) | |
| 193 #define PyBUF_F_CONTIGUOUS (0x0040 | PyBUF_STRIDES) | |
| 194 #define PyBUF_ANY_CONTIGUOUS (0x0080 | PyBUF_STRIDES) | |
| 195 #define PyBUF_INDIRECT (0x0100 | PyBUF_STRIDES) | |
| 196 | |
| 197 #define PyBUF_CONTIG (PyBUF_ND | PyBUF_WRITABLE) | |
| 198 #define PyBUF_CONTIG_RO (PyBUF_ND) | |
| 199 | |
| 200 #define PyBUF_STRIDED (PyBUF_STRIDES | PyBUF_WRITABLE) | |
| 201 #define PyBUF_STRIDED_RO (PyBUF_STRIDES) | |
| 202 | |
| 203 #define PyBUF_RECORDS (PyBUF_STRIDES | PyBUF_WRITABLE | PyBUF_FORMAT) | |
| 204 #define PyBUF_RECORDS_RO (PyBUF_STRIDES | PyBUF_FORMAT) | |
| 205 | |
| 206 #define PyBUF_FULL (PyBUF_INDIRECT | PyBUF_WRITABLE | PyBUF_FORMAT) | |
| 207 #define PyBUF_FULL_RO (PyBUF_INDIRECT | PyBUF_FORMAT) | |
| 208 | |
| 209 | |
| 210 #define PyBUF_READ 0x100 | |
| 211 #define PyBUF_WRITE 0x200 | |
| 212 #define PyBUF_SHADOW 0x400 | |
| 213 /* end Py3k buffer interface */ | |
| 214 | |
| 215 typedef int (*objobjproc)(PyObject *, PyObject *); | |
| 216 typedef int (*visitproc)(PyObject *, void *); | |
| 217 typedef int (*traverseproc)(PyObject *, visitproc, void *); | |
| 218 | |
| 219 typedef struct { | |
| 220 /* For numbers without flag bit Py_TPFLAGS_CHECKTYPES set, all | |
| 221 arguments are guaranteed to be of the object's type (modulo | |
| 222 coercion hacks -- i.e. if the type's coercion function | |
| 223 returns other types, then these are allowed as well). Numbers that | |
| 224 have the Py_TPFLAGS_CHECKTYPES flag bit set should check *both* | |
| 225 arguments for proper type and implement the necessary conversions | |
| 226 in the slot functions themselves. */ | |
| 227 | |
| 228 binaryfunc nb_add; | |
| 229 binaryfunc nb_subtract; | |
| 230 binaryfunc nb_multiply; | |
| 231 binaryfunc nb_divide; | |
| 232 binaryfunc nb_remainder; | |
| 233 binaryfunc nb_divmod; | |
| 234 ternaryfunc nb_power; | |
| 235 unaryfunc nb_negative; | |
| 236 unaryfunc nb_positive; | |
| 237 unaryfunc nb_absolute; | |
| 238 inquiry nb_nonzero; | |
| 239 unaryfunc nb_invert; | |
| 240 binaryfunc nb_lshift; | |
| 241 binaryfunc nb_rshift; | |
| 242 binaryfunc nb_and; | |
| 243 binaryfunc nb_xor; | |
| 244 binaryfunc nb_or; | |
| 245 coercion nb_coerce; | |
| 246 unaryfunc nb_int; | |
| 247 unaryfunc nb_long; | |
| 248 unaryfunc nb_float; | |
| 249 unaryfunc nb_oct; | |
| 250 unaryfunc nb_hex; | |
| 251 /* Added in release 2.0 */ | |
| 252 binaryfunc nb_inplace_add; | |
| 253 binaryfunc nb_inplace_subtract; | |
| 254 binaryfunc nb_inplace_multiply; | |
| 255 binaryfunc nb_inplace_divide; | |
| 256 binaryfunc nb_inplace_remainder; | |
| 257 ternaryfunc nb_inplace_power; | |
| 258 binaryfunc nb_inplace_lshift; | |
| 259 binaryfunc nb_inplace_rshift; | |
| 260 binaryfunc nb_inplace_and; | |
| 261 binaryfunc nb_inplace_xor; | |
| 262 binaryfunc nb_inplace_or; | |
| 263 | |
| 264 /* Added in release 2.2 */ | |
| 265 /* The following require the Py_TPFLAGS_HAVE_CLASS flag */ | |
| 266 binaryfunc nb_floor_divide; | |
| 267 binaryfunc nb_true_divide; | |
| 268 binaryfunc nb_inplace_floor_divide; | |
| 269 binaryfunc nb_inplace_true_divide; | |
| 270 | |
| 271 /* Added in release 2.5 */ | |
| 272 unaryfunc nb_index; | |
| 273 } PyNumberMethods; | |
| 274 | |
| 275 typedef struct { | |
| 276 lenfunc sq_length; | |
| 277 binaryfunc sq_concat; | |
| 278 ssizeargfunc sq_repeat; | |
| 279 ssizeargfunc sq_item; | |
| 280 ssizessizeargfunc sq_slice; | |
| 281 ssizeobjargproc sq_ass_item; | |
| 282 ssizessizeobjargproc sq_ass_slice; | |
| 283 objobjproc sq_contains; | |
| 284 /* Added in release 2.0 */ | |
| 285 binaryfunc sq_inplace_concat; | |
| 286 ssizeargfunc sq_inplace_repeat; | |
| 287 } PySequenceMethods; | |
| 288 | |
| 289 typedef struct { | |
| 290 lenfunc mp_length; | |
| 291 binaryfunc mp_subscript; | |
| 292 objobjargproc mp_ass_subscript; | |
| 293 } PyMappingMethods; | |
| 294 | |
| 295 typedef struct { | |
| 296 readbufferproc bf_getreadbuffer; | |
| 297 writebufferproc bf_getwritebuffer; | |
| 298 segcountproc bf_getsegcount; | |
| 299 charbufferproc bf_getcharbuffer; | |
| 300 getbufferproc bf_getbuffer; | |
| 301 releasebufferproc bf_releasebuffer; | |
| 302 } PyBufferProcs; | |
| 303 | |
| 304 | |
| 305 typedef void (*freefunc)(void *); | |
| 306 typedef void (*destructor)(PyObject *); | |
| 307 typedef int (*printfunc)(PyObject *, FILE *, int); | |
| 308 typedef PyObject *(*getattrfunc)(PyObject *, char *); | |
| 309 typedef PyObject *(*getattrofunc)(PyObject *, PyObject *); | |
| 310 typedef int (*setattrfunc)(PyObject *, char *, PyObject *); | |
| 311 typedef int (*setattrofunc)(PyObject *, PyObject *, PyObject *); | |
| 312 typedef int (*cmpfunc)(PyObject *, PyObject *); | |
| 313 typedef PyObject *(*reprfunc)(PyObject *); | |
| 314 typedef long (*hashfunc)(PyObject *); | |
| 315 typedef PyObject *(*richcmpfunc) (PyObject *, PyObject *, int); | |
| 316 typedef PyObject *(*getiterfunc) (PyObject *); | |
| 317 typedef PyObject *(*iternextfunc) (PyObject *); | |
| 318 typedef PyObject *(*descrgetfunc) (PyObject *, PyObject *, PyObject *); | |
| 319 typedef int (*descrsetfunc) (PyObject *, PyObject *, PyObject *); | |
| 320 typedef int (*initproc)(PyObject *, PyObject *, PyObject *); | |
| 321 typedef PyObject *(*newfunc)(struct _typeobject *, PyObject *, PyObject *); | |
| 322 typedef PyObject *(*allocfunc)(struct _typeobject *, Py_ssize_t); | |
| 323 | |
| 324 typedef struct _typeobject { | |
| 325 PyObject_VAR_HEAD | |
| 326 const char *tp_name; /* For printing, in format "<module>.<name>" */ | |
| 327 Py_ssize_t tp_basicsize, tp_itemsize; /* For allocation */ | |
| 328 | |
| 329 /* Methods to implement standard operations */ | |
| 330 | |
| 331 destructor tp_dealloc; | |
| 332 printfunc tp_print; | |
| 333 getattrfunc tp_getattr; | |
| 334 setattrfunc tp_setattr; | |
| 335 cmpfunc tp_compare; | |
| 336 reprfunc tp_repr; | |
| 337 | |
| 338 /* Method suites for standard classes */ | |
| 339 | |
| 340 PyNumberMethods *tp_as_number; | |
| 341 PySequenceMethods *tp_as_sequence; | |
| 342 PyMappingMethods *tp_as_mapping; | |
| 343 | |
| 344 /* More standard operations (here for binary compatibility) */ | |
| 345 | |
| 346 hashfunc tp_hash; | |
| 347 ternaryfunc tp_call; | |
| 348 reprfunc tp_str; | |
| 349 getattrofunc tp_getattro; | |
| 350 setattrofunc tp_setattro; | |
| 351 | |
| 352 /* Functions to access object as input/output buffer */ | |
| 353 PyBufferProcs *tp_as_buffer; | |
| 354 | |
| 355 /* Flags to define presence of optional/expanded features */ | |
| 356 long tp_flags; | |
| 357 | |
| 358 const char *tp_doc; /* Documentation string */ | |
| 359 | |
| 360 /* Assigned meaning in release 2.0 */ | |
| 361 /* call function for all accessible objects */ | |
| 362 traverseproc tp_traverse; | |
| 363 | |
| 364 /* delete references to contained objects */ | |
| 365 inquiry tp_clear; | |
| 366 | |
| 367 /* Assigned meaning in release 2.1 */ | |
| 368 /* rich comparisons */ | |
| 369 richcmpfunc tp_richcompare; | |
| 370 | |
| 371 /* weak reference enabler */ | |
| 372 Py_ssize_t tp_weaklistoffset; | |
| 373 | |
| 374 /* Added in release 2.2 */ | |
| 375 /* Iterators */ | |
| 376 getiterfunc tp_iter; | |
| 377 iternextfunc tp_iternext; | |
| 378 | |
| 379 /* Attribute descriptor and subclassing stuff */ | |
| 380 struct PyMethodDef *tp_methods; | |
| 381 struct PyMemberDef *tp_members; | |
| 382 struct PyGetSetDef *tp_getset; | |
| 383 struct _typeobject *tp_base; | |
| 384 PyObject *tp_dict; | |
| 385 descrgetfunc tp_descr_get; | |
| 386 descrsetfunc tp_descr_set; | |
| 387 Py_ssize_t tp_dictoffset; | |
| 388 initproc tp_init; | |
| 389 allocfunc tp_alloc; | |
| 390 newfunc tp_new; | |
| 391 freefunc tp_free; /* Low-level free-memory routine */ | |
| 392 inquiry tp_is_gc; /* For PyObject_IS_GC */ | |
| 393 PyObject *tp_bases; | |
| 394 PyObject *tp_mro; /* method resolution order */ | |
| 395 PyObject *tp_cache; | |
| 396 PyObject *tp_subclasses; | |
| 397 PyObject *tp_weaklist; | |
| 398 destructor tp_del; | |
| 399 | |
| 400 /* Type attribute cache version tag. Added in version 2.6 */ | |
| 401 unsigned int tp_version_tag; | |
| 402 | |
| 403 #ifdef COUNT_ALLOCS | |
| 404 /* these must be last and never explicitly initialized */ | |
| 405 Py_ssize_t tp_allocs; | |
| 406 Py_ssize_t tp_frees; | |
| 407 Py_ssize_t tp_maxalloc; | |
| 408 struct _typeobject *tp_prev; | |
| 409 struct _typeobject *tp_next; | |
| 410 #endif | |
| 411 } PyTypeObject; | |
| 412 | |
| 413 | |
| 414 /* The *real* layout of a type object when allocated on the heap */ | |
| 415 typedef struct _heaptypeobject { | |
| 416 /* Note: there's a dependency on the order of these members | |
| 417 in slotptr() in typeobject.c . */ | |
| 418 PyTypeObject ht_type; | |
| 419 PyNumberMethods as_number; | |
| 420 PyMappingMethods as_mapping; | |
| 421 PySequenceMethods as_sequence; /* as_sequence comes after as_mapping, | |
| 422 so that the mapping wins when both | |
| 423 the mapping and the sequence define | |
| 424 a given operator (e.g. __getitem__). | |
| 425 see add_operators() in typeobject.c . */ | |
| 426 PyBufferProcs as_buffer; | |
| 427 PyObject *ht_name, *ht_slots; | |
| 428 /* here are optional user slots, followed by the members. */ | |
| 429 } PyHeapTypeObject; | |
| 430 | |
| 431 /* access macro to the members which are floating "behind" the object */ | |
| 432 #define PyHeapType_GET_MEMBERS(etype) \ | |
| 433 ((PyMemberDef *)(((char *)etype) + Py_TYPE(etype)->tp_basicsize)) | |
| 434 | |
| 435 | |
| 436 /* Generic type check */ | |
| 437 PyAPI_FUNC(int) PyType_IsSubtype(PyTypeObject *, PyTypeObject *); | |
| 438 #define PyObject_TypeCheck(ob, tp) \ | |
| 439 (Py_TYPE(ob) == (tp) || PyType_IsSubtype(Py_TYPE(ob), (tp))) | |
| 440 | |
| 441 PyAPI_DATA(PyTypeObject) PyType_Type; /* built-in 'type' */ | |
| 442 PyAPI_DATA(PyTypeObject) PyBaseObject_Type; /* built-in 'object' */ | |
| 443 PyAPI_DATA(PyTypeObject) PySuper_Type; /* built-in 'super' */ | |
| 444 | |
| 445 #define PyType_Check(op) \ | |
| 446 PyType_FastSubclass(Py_TYPE(op), Py_TPFLAGS_TYPE_SUBCLASS) | |
| 447 #define PyType_CheckExact(op) (Py_TYPE(op) == &PyType_Type) | |
| 448 | |
| 449 PyAPI_FUNC(int) PyType_Ready(PyTypeObject *); | |
| 450 PyAPI_FUNC(PyObject *) PyType_GenericAlloc(PyTypeObject *, Py_ssize_t); | |
| 451 PyAPI_FUNC(PyObject *) PyType_GenericNew(PyTypeObject *, | |
| 452 PyObject *, PyObject *); | |
| 453 PyAPI_FUNC(PyObject *) _PyType_Lookup(PyTypeObject *, PyObject *); | |
| 454 PyAPI_FUNC(PyObject *) _PyObject_LookupSpecial(PyObject *, char *, PyObject **); | |
| 455 PyAPI_FUNC(unsigned int) PyType_ClearCache(void); | |
| 456 PyAPI_FUNC(void) PyType_Modified(PyTypeObject *); | |
| 457 | |
| 458 /* Generic operations on objects */ | |
| 459 PyAPI_FUNC(int) PyObject_Print(PyObject *, FILE *, int); | |
| 460 PyAPI_FUNC(void) _PyObject_Dump(PyObject *); | |
| 461 PyAPI_FUNC(PyObject *) PyObject_Repr(PyObject *); | |
| 462 PyAPI_FUNC(PyObject *) _PyObject_Str(PyObject *); | |
| 463 PyAPI_FUNC(PyObject *) PyObject_Str(PyObject *); | |
| 464 #define PyObject_Bytes PyObject_Str | |
| 465 #ifdef Py_USING_UNICODE | |
| 466 PyAPI_FUNC(PyObject *) PyObject_Unicode(PyObject *); | |
| 467 #endif | |
| 468 PyAPI_FUNC(int) PyObject_Compare(PyObject *, PyObject *); | |
| 469 PyAPI_FUNC(PyObject *) PyObject_RichCompare(PyObject *, PyObject *, int); | |
| 470 PyAPI_FUNC(int) PyObject_RichCompareBool(PyObject *, PyObject *, int); | |
| 471 PyAPI_FUNC(PyObject *) PyObject_GetAttrString(PyObject *, const char *); | |
| 472 PyAPI_FUNC(int) PyObject_SetAttrString(PyObject *, const char *, PyObject *); | |
| 473 PyAPI_FUNC(int) PyObject_HasAttrString(PyObject *, const char *); | |
| 474 PyAPI_FUNC(PyObject *) PyObject_GetAttr(PyObject *, PyObject *); | |
| 475 PyAPI_FUNC(int) PyObject_SetAttr(PyObject *, PyObject *, PyObject *); | |
| 476 PyAPI_FUNC(int) PyObject_HasAttr(PyObject *, PyObject *); | |
| 477 PyAPI_FUNC(PyObject **) _PyObject_GetDictPtr(PyObject *); | |
| 478 PyAPI_FUNC(PyObject *) PyObject_SelfIter(PyObject *); | |
| 479 PyAPI_FUNC(PyObject *) _PyObject_NextNotImplemented(PyObject *); | |
| 480 PyAPI_FUNC(PyObject *) PyObject_GenericGetAttr(PyObject *, PyObject *); | |
| 481 PyAPI_FUNC(int) PyObject_GenericSetAttr(PyObject *, | |
| 482 PyObject *, PyObject *); | |
| 483 PyAPI_FUNC(long) PyObject_Hash(PyObject *); | |
| 484 PyAPI_FUNC(long) PyObject_HashNotImplemented(PyObject *); | |
| 485 PyAPI_FUNC(int) PyObject_IsTrue(PyObject *); | |
| 486 PyAPI_FUNC(int) PyObject_Not(PyObject *); | |
| 487 PyAPI_FUNC(int) PyCallable_Check(PyObject *); | |
| 488 PyAPI_FUNC(int) PyNumber_Coerce(PyObject **, PyObject **); | |
| 489 PyAPI_FUNC(int) PyNumber_CoerceEx(PyObject **, PyObject **); | |
| 490 | |
| 491 PyAPI_FUNC(void) PyObject_ClearWeakRefs(PyObject *); | |
| 492 | |
| 493 /* A slot function whose address we need to compare */ | |
| 494 extern int _PyObject_SlotCompare(PyObject *, PyObject *); | |
| 495 /* Same as PyObject_Generic{Get,Set}Attr, but passing the attributes | |
| 496 dict as the last parameter. */ | |
| 497 PyAPI_FUNC(PyObject *) | |
| 498 _PyObject_GenericGetAttrWithDict(PyObject *, PyObject *, PyObject *); | |
| 499 PyAPI_FUNC(int) | |
| 500 _PyObject_GenericSetAttrWithDict(PyObject *, PyObject *, | |
| 501 PyObject *, PyObject *); | |
| 502 | |
| 503 | |
| 504 /* PyObject_Dir(obj) acts like Python __builtin__.dir(obj), returning a | |
| 505 list of strings. PyObject_Dir(NULL) is like __builtin__.dir(), | |
| 506 returning the names of the current locals. In this case, if there are | |
| 507 no current locals, NULL is returned, and PyErr_Occurred() is false. | |
| 508 */ | |
| 509 PyAPI_FUNC(PyObject *) PyObject_Dir(PyObject *); | |
| 510 | |
| 511 | |
| 512 /* Helpers for printing recursive container types */ | |
| 513 PyAPI_FUNC(int) Py_ReprEnter(PyObject *); | |
| 514 PyAPI_FUNC(void) Py_ReprLeave(PyObject *); | |
| 515 | |
| 516 /* Helpers for hash functions */ | |
| 517 PyAPI_FUNC(long) _Py_HashDouble(double); | |
| 518 PyAPI_FUNC(long) _Py_HashPointer(void*); | |
| 519 | |
| 520 typedef struct { | |
| 521 long prefix; | |
| 522 long suffix; | |
| 523 } _Py_HashSecret_t; | |
| 524 PyAPI_DATA(_Py_HashSecret_t) _Py_HashSecret; | |
| 525 | |
| 526 #ifdef Py_DEBUG | |
| 527 PyAPI_DATA(int) _Py_HashSecret_Initialized; | |
| 528 #endif | |
| 529 | |
| 530 /* Helper for passing objects to printf and the like. | |
| 531 Leaks refcounts. Don't use it! | |
| 532 */ | |
| 533 #define PyObject_REPR(obj) PyString_AS_STRING(PyObject_Repr(obj)) | |
| 534 | |
| 535 /* Flag bits for printing: */ | |
| 536 #define Py_PRINT_RAW 1 /* No string quotes etc. */ | |
| 537 | |
| 538 /* | |
| 539 `Type flags (tp_flags) | |
| 540 | |
| 541 These flags are used to extend the type structure in a backwards-compatible | |
| 542 fashion. Extensions can use the flags to indicate (and test) when a given | |
| 543 type structure contains a new feature. The Python core will use these when | |
| 544 introducing new functionality between major revisions (to avoid mid-version | |
| 545 changes in the PYTHON_API_VERSION). | |
| 546 | |
| 547 Arbitration of the flag bit positions will need to be coordinated among | |
| 548 all extension writers who publically release their extensions (this will | |
| 549 be fewer than you might expect!).. | |
| 550 | |
| 551 Python 1.5.2 introduced the bf_getcharbuffer slot into PyBufferProcs. | |
| 552 | |
| 553 Type definitions should use Py_TPFLAGS_DEFAULT for their tp_flags value. | |
| 554 | |
| 555 Code can use PyType_HasFeature(type_ob, flag_value) to test whether the | |
| 556 given type object has a specified feature. | |
| 557 | |
| 558 NOTE: when building the core, Py_TPFLAGS_DEFAULT includes | |
| 559 Py_TPFLAGS_HAVE_VERSION_TAG; outside the core, it doesn't. This is so | |
| 560 that extensions that modify tp_dict of their own types directly don't | |
| 561 break, since this was allowed in 2.5. In 3.0 they will have to | |
| 562 manually remove this flag though! | |
| 563 */ | |
| 564 | |
| 565 /* PyBufferProcs contains bf_getcharbuffer */ | |
| 566 #define Py_TPFLAGS_HAVE_GETCHARBUFFER (1L<<0) | |
| 567 | |
| 568 /* PySequenceMethods contains sq_contains */ | |
| 569 #define Py_TPFLAGS_HAVE_SEQUENCE_IN (1L<<1) | |
| 570 | |
| 571 /* This is here for backwards compatibility. Extensions that use the old GC | |
| 572 * API will still compile but the objects will not be tracked by the GC. */ | |
| 573 #define Py_TPFLAGS_GC 0 /* used to be (1L<<2) */ | |
| 574 | |
| 575 /* PySequenceMethods and PyNumberMethods contain in-place operators */ | |
| 576 #define Py_TPFLAGS_HAVE_INPLACEOPS (1L<<3) | |
| 577 | |
| 578 /* PyNumberMethods do their own coercion */ | |
| 579 #define Py_TPFLAGS_CHECKTYPES (1L<<4) | |
| 580 | |
| 581 /* tp_richcompare is defined */ | |
| 582 #define Py_TPFLAGS_HAVE_RICHCOMPARE (1L<<5) | |
| 583 | |
| 584 /* Objects which are weakly referencable if their tp_weaklistoffset is >0 */ | |
| 585 #define Py_TPFLAGS_HAVE_WEAKREFS (1L<<6) | |
| 586 | |
| 587 /* tp_iter is defined */ | |
| 588 #define Py_TPFLAGS_HAVE_ITER (1L<<7) | |
| 589 | |
| 590 /* New members introduced by Python 2.2 exist */ | |
| 591 #define Py_TPFLAGS_HAVE_CLASS (1L<<8) | |
| 592 | |
| 593 /* Set if the type object is dynamically allocated */ | |
| 594 #define Py_TPFLAGS_HEAPTYPE (1L<<9) | |
| 595 | |
| 596 /* Set if the type allows subclassing */ | |
| 597 #define Py_TPFLAGS_BASETYPE (1L<<10) | |
| 598 | |
| 599 /* Set if the type is 'ready' -- fully initialized */ | |
| 600 #define Py_TPFLAGS_READY (1L<<12) | |
| 601 | |
| 602 /* Set while the type is being 'readied', to prevent recursive ready calls */ | |
| 603 #define Py_TPFLAGS_READYING (1L<<13) | |
| 604 | |
| 605 /* Objects support garbage collection (see objimp.h) */ | |
| 606 #define Py_TPFLAGS_HAVE_GC (1L<<14) | |
| 607 | |
| 608 /* These two bits are preserved for Stackless Python, next after this is 17 */ | |
| 609 #ifdef STACKLESS | |
| 610 #define Py_TPFLAGS_HAVE_STACKLESS_EXTENSION (3L<<15) | |
| 611 #else | |
| 612 #define Py_TPFLAGS_HAVE_STACKLESS_EXTENSION 0 | |
| 613 #endif | |
| 614 | |
| 615 /* Objects support nb_index in PyNumberMethods */ | |
| 616 #define Py_TPFLAGS_HAVE_INDEX (1L<<17) | |
| 617 | |
| 618 /* Objects support type attribute cache */ | |
| 619 #define Py_TPFLAGS_HAVE_VERSION_TAG (1L<<18) | |
| 620 #define Py_TPFLAGS_VALID_VERSION_TAG (1L<<19) | |
| 621 | |
| 622 /* Type is abstract and cannot be instantiated */ | |
| 623 #define Py_TPFLAGS_IS_ABSTRACT (1L<<20) | |
| 624 | |
| 625 /* Has the new buffer protocol */ | |
| 626 #define Py_TPFLAGS_HAVE_NEWBUFFER (1L<<21) | |
| 627 | |
| 628 /* These flags are used to determine if a type is a subclass. */ | |
| 629 #define Py_TPFLAGS_INT_SUBCLASS (1L<<23) | |
| 630 #define Py_TPFLAGS_LONG_SUBCLASS (1L<<24) | |
| 631 #define Py_TPFLAGS_LIST_SUBCLASS (1L<<25) | |
| 632 #define Py_TPFLAGS_TUPLE_SUBCLASS (1L<<26) | |
| 633 #define Py_TPFLAGS_STRING_SUBCLASS (1L<<27) | |
| 634 #define Py_TPFLAGS_UNICODE_SUBCLASS (1L<<28) | |
| 635 #define Py_TPFLAGS_DICT_SUBCLASS (1L<<29) | |
| 636 #define Py_TPFLAGS_BASE_EXC_SUBCLASS (1L<<30) | |
| 637 #define Py_TPFLAGS_TYPE_SUBCLASS (1L<<31) | |
| 638 | |
| 639 #define Py_TPFLAGS_DEFAULT_EXTERNAL ( \ | |
| 640 Py_TPFLAGS_HAVE_GETCHARBUFFER | \ | |
| 641 Py_TPFLAGS_HAVE_SEQUENCE_IN | \ | |
| 642 Py_TPFLAGS_HAVE_INPLACEOPS | \ | |
| 643 Py_TPFLAGS_HAVE_RICHCOMPARE | \ | |
| 644 Py_TPFLAGS_HAVE_WEAKREFS | \ | |
| 645 Py_TPFLAGS_HAVE_ITER | \ | |
| 646 Py_TPFLAGS_HAVE_CLASS | \ | |
| 647 Py_TPFLAGS_HAVE_STACKLESS_EXTENSION | \ | |
| 648 Py_TPFLAGS_HAVE_INDEX | \ | |
| 649 0) | |
| 650 #define Py_TPFLAGS_DEFAULT_CORE (Py_TPFLAGS_DEFAULT_EXTERNAL | \ | |
| 651 Py_TPFLAGS_HAVE_VERSION_TAG) | |
| 652 | |
| 653 #ifdef Py_BUILD_CORE | |
| 654 #define Py_TPFLAGS_DEFAULT Py_TPFLAGS_DEFAULT_CORE | |
| 655 #else | |
| 656 #define Py_TPFLAGS_DEFAULT Py_TPFLAGS_DEFAULT_EXTERNAL | |
| 657 #endif | |
| 658 | |
| 659 #define PyType_HasFeature(t,f) (((t)->tp_flags & (f)) != 0) | |
| 660 #define PyType_FastSubclass(t,f) PyType_HasFeature(t,f) | |
| 661 | |
| 662 | |
| 663 /* | |
| 664 The macros Py_INCREF(op) and Py_DECREF(op) are used to increment or decrement | |
| 665 reference counts. Py_DECREF calls the object's deallocator function when | |
| 666 the refcount falls to 0; for | |
| 667 objects that don't contain references to other objects or heap memory | |
| 668 this can be the standard function free(). Both macros can be used | |
| 669 wherever a void expression is allowed. The argument must not be a | |
| 670 NULL pointer. If it may be NULL, use Py_XINCREF/Py_XDECREF instead. | |
| 671 The macro _Py_NewReference(op) initialize reference counts to 1, and | |
| 672 in special builds (Py_REF_DEBUG, Py_TRACE_REFS) performs additional | |
| 673 bookkeeping appropriate to the special build. | |
| 674 | |
| 675 We assume that the reference count field can never overflow; this can | |
| 676 be proven when the size of the field is the same as the pointer size, so | |
| 677 we ignore the possibility. Provided a C int is at least 32 bits (which | |
| 678 is implicitly assumed in many parts of this code), that's enough for | |
| 679 about 2**31 references to an object. | |
| 680 | |
| 681 XXX The following became out of date in Python 2.2, but I'm not sure | |
| 682 XXX what the full truth is now. Certainly, heap-allocated type objects | |
| 683 XXX can and should be deallocated. | |
| 684 Type objects should never be deallocated; the type pointer in an object | |
| 685 is not considered to be a reference to the type object, to save | |
| 686 complications in the deallocation function. (This is actually a | |
| 687 decision that's up to the implementer of each new type so if you want, | |
| 688 you can count such references to the type object.) | |
| 689 | |
| 690 *** WARNING*** The Py_DECREF macro must have a side-effect-free argument | |
| 691 since it may evaluate its argument multiple times. (The alternative | |
| 692 would be to mace it a proper function or assign it to a global temporary | |
| 693 variable first, both of which are slower; and in a multi-threaded | |
| 694 environment the global variable trick is not safe.) | |
| 695 */ | |
| 696 | |
| 697 /* First define a pile of simple helper macros, one set per special | |
| 698 * build symbol. These either expand to the obvious things, or to | |
| 699 * nothing at all when the special mode isn't in effect. The main | |
| 700 * macros can later be defined just once then, yet expand to different | |
| 701 * things depending on which special build options are and aren't in effect. | |
| 702 * Trust me <wink>: while painful, this is 20x easier to understand than, | |
| 703 * e.g, defining _Py_NewReference five different times in a maze of nested | |
| 704 * #ifdefs (we used to do that -- it was impenetrable). | |
| 705 */ | |
| 706 #ifdef Py_REF_DEBUG | |
| 707 PyAPI_DATA(Py_ssize_t) _Py_RefTotal; | |
| 708 PyAPI_FUNC(void) _Py_NegativeRefcount(const char *fname, | |
| 709 int lineno, PyObject *op); | |
| 710 PyAPI_FUNC(PyObject *) _PyDict_Dummy(void); | |
| 711 PyAPI_FUNC(PyObject *) _PySet_Dummy(void); | |
| 712 PyAPI_FUNC(Py_ssize_t) _Py_GetRefTotal(void); | |
| 713 #define _Py_INC_REFTOTAL _Py_RefTotal++ | |
| 714 #define _Py_DEC_REFTOTAL _Py_RefTotal-- | |
| 715 #define _Py_REF_DEBUG_COMMA , | |
| 716 #define _Py_CHECK_REFCNT(OP) \ | |
| 717 { if (((PyObject*)OP)->ob_refcnt < 0) \ | |
| 718 _Py_NegativeRefcount(__FILE__, __LINE__, \ | |
| 719 (PyObject *)(OP)); \ | |
| 720 } | |
| 721 #else | |
| 722 #define _Py_INC_REFTOTAL | |
| 723 #define _Py_DEC_REFTOTAL | |
| 724 #define _Py_REF_DEBUG_COMMA | |
| 725 #define _Py_CHECK_REFCNT(OP) /* a semicolon */; | |
| 726 #endif /* Py_REF_DEBUG */ | |
| 727 | |
| 728 #ifdef COUNT_ALLOCS | |
| 729 PyAPI_FUNC(void) inc_count(PyTypeObject *); | |
| 730 PyAPI_FUNC(void) dec_count(PyTypeObject *); | |
| 731 #define _Py_INC_TPALLOCS(OP) inc_count(Py_TYPE(OP)) | |
| 732 #define _Py_INC_TPFREES(OP) dec_count(Py_TYPE(OP)) | |
| 733 #define _Py_DEC_TPFREES(OP) Py_TYPE(OP)->tp_frees-- | |
| 734 #define _Py_COUNT_ALLOCS_COMMA , | |
| 735 #else | |
| 736 #define _Py_INC_TPALLOCS(OP) | |
| 737 #define _Py_INC_TPFREES(OP) | |
| 738 #define _Py_DEC_TPFREES(OP) | |
| 739 #define _Py_COUNT_ALLOCS_COMMA | |
| 740 #endif /* COUNT_ALLOCS */ | |
| 741 | |
| 742 #ifdef Py_TRACE_REFS | |
| 743 /* Py_TRACE_REFS is such major surgery that we call external routines. */ | |
| 744 PyAPI_FUNC(void) _Py_NewReference(PyObject *); | |
| 745 PyAPI_FUNC(void) _Py_ForgetReference(PyObject *); | |
| 746 PyAPI_FUNC(void) _Py_Dealloc(PyObject *); | |
| 747 PyAPI_FUNC(void) _Py_PrintReferences(FILE *); | |
| 748 PyAPI_FUNC(void) _Py_PrintReferenceAddresses(FILE *); | |
| 749 PyAPI_FUNC(void) _Py_AddToAllObjects(PyObject *, int force); | |
| 750 | |
| 751 #else | |
| 752 /* Without Py_TRACE_REFS, there's little enough to do that we expand code | |
| 753 * inline. | |
| 754 */ | |
| 755 #define _Py_NewReference(op) ( \ | |
| 756 _Py_INC_TPALLOCS(op) _Py_COUNT_ALLOCS_COMMA \ | |
| 757 _Py_INC_REFTOTAL _Py_REF_DEBUG_COMMA \ | |
| 758 Py_REFCNT(op) = 1) | |
| 759 | |
| 760 #define _Py_ForgetReference(op) _Py_INC_TPFREES(op) | |
| 761 | |
| 762 #define _Py_Dealloc(op) ( \ | |
| 763 _Py_INC_TPFREES(op) _Py_COUNT_ALLOCS_COMMA \ | |
| 764 (*Py_TYPE(op)->tp_dealloc)((PyObject *)(op))) | |
| 765 #endif /* !Py_TRACE_REFS */ | |
| 766 | |
| 767 #define Py_INCREF(op) ( \ | |
| 768 _Py_INC_REFTOTAL _Py_REF_DEBUG_COMMA \ | |
| 769 ((PyObject*)(op))->ob_refcnt++) | |
| 770 | |
| 771 #define Py_DECREF(op) \ | |
| 772 do { \ | |
| 773 if (_Py_DEC_REFTOTAL _Py_REF_DEBUG_COMMA \ | |
| 774 --((PyObject*)(op))->ob_refcnt != 0) \ | |
| 775 _Py_CHECK_REFCNT(op) \ | |
| 776 else \ | |
| 777 _Py_Dealloc((PyObject *)(op)); \ | |
| 778 } while (0) | |
| 779 | |
| 780 /* Safely decref `op` and set `op` to NULL, especially useful in tp_clear | |
| 781 * and tp_dealloc implementatons. | |
| 782 * | |
| 783 * Note that "the obvious" code can be deadly: | |
| 784 * | |
| 785 * Py_XDECREF(op); | |
| 786 * op = NULL; | |
| 787 * | |
| 788 * Typically, `op` is something like self->containee, and `self` is done | |
| 789 * using its `containee` member. In the code sequence above, suppose | |
| 790 * `containee` is non-NULL with a refcount of 1. Its refcount falls to | |
| 791 * 0 on the first line, which can trigger an arbitrary amount of code, | |
| 792 * possibly including finalizers (like __del__ methods or weakref callbacks) | |
| 793 * coded in Python, which in turn can release the GIL and allow other threads | |
| 794 * to run, etc. Such code may even invoke methods of `self` again, or cause | |
| 795 * cyclic gc to trigger, but-- oops! --self->containee still points to the | |
| 796 * object being torn down, and it may be in an insane state while being torn | |
| 797 * down. This has in fact been a rich historic source of miserable (rare & | |
| 798 * hard-to-diagnose) segfaulting (and other) bugs. | |
| 799 * | |
| 800 * The safe way is: | |
| 801 * | |
| 802 * Py_CLEAR(op); | |
| 803 * | |
| 804 * That arranges to set `op` to NULL _before_ decref'ing, so that any code | |
| 805 * triggered as a side-effect of `op` getting torn down no longer believes | |
| 806 * `op` points to a valid object. | |
| 807 * | |
| 808 * There are cases where it's safe to use the naive code, but they're brittle. | |
| 809 * For example, if `op` points to a Python integer, you know that destroying | |
| 810 * one of those can't cause problems -- but in part that relies on that | |
| 811 * Python integers aren't currently weakly referencable. Best practice is | |
| 812 * to use Py_CLEAR() even if you can't think of a reason for why you need to. | |
| 813 */ | |
| 814 #define Py_CLEAR(op) \ | |
| 815 do { \ | |
| 816 if (op) { \ | |
| 817 PyObject *_py_tmp = (PyObject *)(op); \ | |
| 818 (op) = NULL; \ | |
| 819 Py_DECREF(_py_tmp); \ | |
| 820 } \ | |
| 821 } while (0) | |
| 822 | |
| 823 /* Macros to use in case the object pointer may be NULL: */ | |
| 824 #define Py_XINCREF(op) do { if ((op) == NULL) ; else Py_INCREF(op); } while (0) | |
| 825 #define Py_XDECREF(op) do { if ((op) == NULL) ; else Py_DECREF(op); } while (0) | |
| 826 | |
| 827 /* Safely decref `op` and set `op` to `op2`. | |
| 828 * | |
| 829 * As in case of Py_CLEAR "the obvious" code can be deadly: | |
| 830 * | |
| 831 * Py_DECREF(op); | |
| 832 * op = op2; | |
| 833 * | |
| 834 * The safe way is: | |
| 835 * | |
| 836 * Py_SETREF(op, op2); | |
| 837 * | |
| 838 * That arranges to set `op` to `op2` _before_ decref'ing, so that any code | |
| 839 * triggered as a side-effect of `op` getting torn down no longer believes | |
| 840 * `op` points to a valid object. | |
| 841 * | |
| 842 * Py_XSETREF is a variant of Py_SETREF that uses Py_XDECREF instead of | |
| 843 * Py_DECREF. | |
| 844 */ | |
| 845 | |
| 846 #define Py_SETREF(op, op2) \ | |
| 847 do { \ | |
| 848 PyObject *_py_tmp = (PyObject *)(op); \ | |
| 849 (op) = (op2); \ | |
| 850 Py_DECREF(_py_tmp); \ | |
| 851 } while (0) | |
| 852 | |
| 853 #define Py_XSETREF(op, op2) \ | |
| 854 do { \ | |
| 855 PyObject *_py_tmp = (PyObject *)(op); \ | |
| 856 (op) = (op2); \ | |
| 857 Py_XDECREF(_py_tmp); \ | |
| 858 } while (0) | |
| 859 | |
| 860 /* | |
| 861 These are provided as conveniences to Python runtime embedders, so that | |
| 862 they can have object code that is not dependent on Python compilation flags. | |
| 863 */ | |
| 864 PyAPI_FUNC(void) Py_IncRef(PyObject *); | |
| 865 PyAPI_FUNC(void) Py_DecRef(PyObject *); | |
| 866 | |
| 867 /* | |
| 868 _Py_NoneStruct is an object of undefined type which can be used in contexts | |
| 869 where NULL (nil) is not suitable (since NULL often means 'error'). | |
| 870 | |
| 871 Don't forget to apply Py_INCREF() when returning this value!!! | |
| 872 */ | |
| 873 PyAPI_DATA(PyObject) _Py_NoneStruct; /* Don't use this directly */ | |
| 874 #define Py_None (&_Py_NoneStruct) | |
| 875 | |
| 876 /* Macro for returning Py_None from a function */ | |
| 877 #define Py_RETURN_NONE return Py_INCREF(Py_None), Py_None | |
| 878 | |
| 879 /* | |
| 880 Py_NotImplemented is a singleton used to signal that an operation is | |
| 881 not implemented for a given type combination. | |
| 882 */ | |
| 883 PyAPI_DATA(PyObject) _Py_NotImplementedStruct; /* Don't use this directly */ | |
| 884 #define Py_NotImplemented (&_Py_NotImplementedStruct) | |
| 885 | |
| 886 /* Rich comparison opcodes */ | |
| 887 #define Py_LT 0 | |
| 888 #define Py_LE 1 | |
| 889 #define Py_EQ 2 | |
| 890 #define Py_NE 3 | |
| 891 #define Py_GT 4 | |
| 892 #define Py_GE 5 | |
| 893 | |
| 894 /* Maps Py_LT to Py_GT, ..., Py_GE to Py_LE. | |
| 895 * Defined in object.c. | |
| 896 */ | |
| 897 PyAPI_DATA(int) _Py_SwappedOp[]; | |
| 898 | |
| 899 /* | |
| 900 Define staticforward and statichere for source compatibility with old | |
| 901 C extensions. | |
| 902 | |
| 903 The staticforward define was needed to support certain broken C | |
| 904 compilers (notably SCO ODT 3.0, perhaps early AIX as well) botched the | |
| 905 static keyword when it was used with a forward declaration of a static | |
| 906 initialized structure. Standard C allows the forward declaration with | |
| 907 static, and we've decided to stop catering to broken C compilers. | |
| 908 (In fact, we expect that the compilers are all fixed eight years later.) | |
| 909 */ | |
| 910 | |
| 911 #define staticforward static | |
| 912 #define statichere static | |
| 913 | |
| 914 | |
| 915 /* | |
| 916 More conventions | |
| 917 ================ | |
| 918 | |
| 919 Argument Checking | |
| 920 ----------------- | |
| 921 | |
| 922 Functions that take objects as arguments normally don't check for nil | |
| 923 arguments, but they do check the type of the argument, and return an | |
| 924 error if the function doesn't apply to the type. | |
| 925 | |
| 926 Failure Modes | |
| 927 ------------- | |
| 928 | |
| 929 Functions may fail for a variety of reasons, including running out of | |
| 930 memory. This is communicated to the caller in two ways: an error string | |
| 931 is set (see errors.h), and the function result differs: functions that | |
| 932 normally return a pointer return NULL for failure, functions returning | |
| 933 an integer return -1 (which could be a legal return value too!), and | |
| 934 other functions return 0 for success and -1 for failure. | |
| 935 Callers should always check for errors before using the result. If | |
| 936 an error was set, the caller must either explicitly clear it, or pass | |
| 937 the error on to its caller. | |
| 938 | |
| 939 Reference Counts | |
| 940 ---------------- | |
| 941 | |
| 942 It takes a while to get used to the proper usage of reference counts. | |
| 943 | |
| 944 Functions that create an object set the reference count to 1; such new | |
| 945 objects must be stored somewhere or destroyed again with Py_DECREF(). | |
| 946 Some functions that 'store' objects, such as PyTuple_SetItem() and | |
| 947 PyList_SetItem(), | |
| 948 don't increment the reference count of the object, since the most | |
| 949 frequent use is to store a fresh object. Functions that 'retrieve' | |
| 950 objects, such as PyTuple_GetItem() and PyDict_GetItemString(), also | |
| 951 don't increment | |
| 952 the reference count, since most frequently the object is only looked at | |
| 953 quickly. Thus, to retrieve an object and store it again, the caller | |
| 954 must call Py_INCREF() explicitly. | |
| 955 | |
| 956 NOTE: functions that 'consume' a reference count, like | |
| 957 PyList_SetItem(), consume the reference even if the object wasn't | |
| 958 successfully stored, to simplify error handling. | |
| 959 | |
| 960 It seems attractive to make other functions that take an object as | |
| 961 argument consume a reference count; however, this may quickly get | |
| 962 confusing (even the current practice is already confusing). Consider | |
| 963 it carefully, it may save lots of calls to Py_INCREF() and Py_DECREF() at | |
| 964 times. | |
| 965 */ | |
| 966 | |
| 967 | |
| 968 /* Trashcan mechanism, thanks to Christian Tismer. | |
| 969 | |
| 970 When deallocating a container object, it's possible to trigger an unbounded | |
| 971 chain of deallocations, as each Py_DECREF in turn drops the refcount on "the | |
| 972 next" object in the chain to 0. This can easily lead to stack faults, and | |
| 973 especially in threads (which typically have less stack space to work with). | |
| 974 | |
| 975 A container object that participates in cyclic gc can avoid this by | |
| 976 bracketing the body of its tp_dealloc function with a pair of macros: | |
| 977 | |
| 978 static void | |
| 979 mytype_dealloc(mytype *p) | |
| 980 { | |
| 981 ... declarations go here ... | |
| 982 | |
| 983 PyObject_GC_UnTrack(p); // must untrack first | |
| 984 Py_TRASHCAN_SAFE_BEGIN(p) | |
| 985 ... The body of the deallocator goes here, including all calls ... | |
| 986 ... to Py_DECREF on contained objects. ... | |
| 987 Py_TRASHCAN_SAFE_END(p) | |
| 988 } | |
| 989 | |
| 990 CAUTION: Never return from the middle of the body! If the body needs to | |
| 991 "get out early", put a label immediately before the Py_TRASHCAN_SAFE_END | |
| 992 call, and goto it. Else the call-depth counter (see below) will stay | |
| 993 above 0 forever, and the trashcan will never get emptied. | |
| 994 | |
| 995 How it works: The BEGIN macro increments a call-depth counter. So long | |
| 996 as this counter is small, the body of the deallocator is run directly without | |
| 997 further ado. But if the counter gets large, it instead adds p to a list of | |
| 998 objects to be deallocated later, skips the body of the deallocator, and | |
| 999 resumes execution after the END macro. The tp_dealloc routine then returns | |
| 1000 without deallocating anything (and so unbounded call-stack depth is avoided). | |
| 1001 | |
| 1002 When the call stack finishes unwinding again, code generated by the END macro | |
| 1003 notices this, and calls another routine to deallocate all the objects that | |
| 1004 may have been added to the list of deferred deallocations. In effect, a | |
| 1005 chain of N deallocations is broken into N / PyTrash_UNWIND_LEVEL pieces, | |
| 1006 with the call stack never exceeding a depth of PyTrash_UNWIND_LEVEL. | |
| 1007 */ | |
| 1008 | |
| 1009 /* This is the old private API, invoked by the macros before 2.7.4. | |
| 1010 Kept for binary compatibility of extensions. */ | |
| 1011 PyAPI_FUNC(void) _PyTrash_deposit_object(PyObject*); | |
| 1012 PyAPI_FUNC(void) _PyTrash_destroy_chain(void); | |
| 1013 PyAPI_DATA(int) _PyTrash_delete_nesting; | |
| 1014 PyAPI_DATA(PyObject *) _PyTrash_delete_later; | |
| 1015 | |
| 1016 /* The new thread-safe private API, invoked by the macros below. */ | |
| 1017 PyAPI_FUNC(void) _PyTrash_thread_deposit_object(PyObject*); | |
| 1018 PyAPI_FUNC(void) _PyTrash_thread_destroy_chain(void); | |
| 1019 | |
| 1020 #define PyTrash_UNWIND_LEVEL 50 | |
| 1021 | |
| 1022 /* Note the workaround for when the thread state is NULL (issue #17703) */ | |
| 1023 #define Py_TRASHCAN_SAFE_BEGIN(op) \ | |
| 1024 do { \ | |
| 1025 PyThreadState *_tstate = PyThreadState_GET(); \ | |
| 1026 if (!_tstate || \ | |
| 1027 _tstate->trash_delete_nesting < PyTrash_UNWIND_LEVEL) { \ | |
| 1028 if (_tstate) \ | |
| 1029 ++_tstate->trash_delete_nesting; | |
| 1030 /* The body of the deallocator is here. */ | |
| 1031 #define Py_TRASHCAN_SAFE_END(op) \ | |
| 1032 if (_tstate) { \ | |
| 1033 --_tstate->trash_delete_nesting; \ | |
| 1034 if (_tstate->trash_delete_later \ | |
| 1035 && _tstate->trash_delete_nesting <= 0) \ | |
| 1036 _PyTrash_thread_destroy_chain(); \ | |
| 1037 } \ | |
| 1038 } \ | |
| 1039 else \ | |
| 1040 _PyTrash_thread_deposit_object((PyObject*)op); \ | |
| 1041 } while (0); | |
| 1042 | |
| 1043 #ifdef __cplusplus | |
| 1044 } | |
| 1045 #endif | |
| 1046 #endif /* !Py_OBJECT_H */ |
