Objects/methodobject.c

   1 /***********************************************************
   2 Copyright 1991-1995 by Stichting Mathematisch Centrum, Amsterdam,
   3 The Netherlands.
   4
   5                         All Rights Reserved
   6
   7 Permission to use, copy, modify, and distribute this software and its
   8 documentation for any purpose and without fee is hereby granted,
   9 provided that the above copyright notice appear in all copies and that
  10 both that copyright notice and this permission notice appear in
  11 supporting documentation, and that the names of Stichting Mathematisch
  12 Centrum or CWI or Corporation for National Research Initiatives or
  13 CNRI not be used in advertising or publicity pertaining to
  14 distribution of the software without specific, written prior
  15 permission.
  16
  17 While CWI is the initial source for this software, a modified version
  18 is made available by the Corporation for National Research Initiatives
  19 (CNRI) at the Internet address ftp://ftp.python.org.
  20
  21 STICHTING MATHEMATISCH CENTRUM AND CNRI DISCLAIM ALL WARRANTIES WITH
  22 REGARD TO THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF
  23 MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH
  24 CENTRUM OR CNRI BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL
  25 DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
  26 PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
  27 TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
  28 PERFORMANCE OF THIS SOFTWARE.
  29
  30 ******************************************************************/
  31
  32 /* Method object implementation */
  33
  34 #include "Python.h"
  35
  36 #include "token.h"
  37
  38 static PyCFunctionObject *free_list = NULL;
  39
  40 PyObject *
  41 PyCFunction_New(ml, self)
  42         PyMethodDef *ml;
  43         PyObject *self;
  44 {
  45         PyCFunctionObject *op;
  46         op = free_list;
  47         if (op != NULL) {
  48                 free_list = (PyCFunctionObject *)(op->m_self);
  49                 op->ob_type = &PyCFunction_Type;
  50                 _Py_NewReference(op);
  51         }
  52         else {
  53                 op = PyObject_NEW(PyCFunctionObject, &PyCFunction_Type);
  54                 if (op == NULL)
  55                         return NULL;
  56         }
  57         op->m_ml = ml;
  58         Py_XINCREF(self);
  59         op->m_self = self;
  60         return (PyObject *)op;
  61 }
  62
  63 PyCFunction
  64 PyCFunction_GetFunction(op)
  65         PyObject *op;
  66 {
  67         if (!PyCFunction_Check(op)) {
  68                 PyErr_BadInternalCall();
  69                 return NULL;
  70         }
  71         return ((PyCFunctionObject *)op) -> m_ml -> ml_meth;
  72 }
  73
  74 PyObject *
  75 PyCFunction_GetSelf(op)
  76         PyObject *op;
  77 {
  78         if (!PyCFunction_Check(op)) {
  79                 PyErr_BadInternalCall();
  80                 return NULL;
  81         }
  82         return ((PyCFunctionObject *)op) -> m_self;
  83 }
  84
  85 int
  86 PyCFunction_GetFlags(op)
  87         PyObject *op;
  88 {
  89         if (!PyCFunction_Check(op)) {
  90                 PyErr_BadInternalCall();
  91                 return -1;
  92         }
  93         return ((PyCFunctionObject *)op) -> m_ml -> ml_flags;
  94 }
  95
  96 /* Methods (the standard built-in methods, that is) */
  97
  98 static void
  99 meth_dealloc(m)
 100         PyCFunctionObject *m;
 101 {
 102         Py_XDECREF(m->m_self);
 103         m->m_self = (PyObject *)free_list;
 104         free_list = m;
 105 }
 106
 107 static PyObject *
 108 meth_getattr(m, name)
 109         PyCFunctionObject *m;
 110         char *name;
 111 {
 112         if (strcmp(name, "__name__") == 0) {
 113                 return PyString_FromString(m->m_ml->ml_name);
 114         }
 115         if (strcmp(name, "__doc__") == 0) {
 116                 char *doc = m->m_ml->ml_doc;
 117                 if (doc != NULL)
 118                         return PyString_FromString(doc);
 119                 Py_INCREF(Py_None);
 120                 return Py_None;
 121         }
 122         if (strcmp(name, "__self__") == 0) {
 123                 PyObject *self;
 124                 if (PyEval_GetRestricted()) {
 125                         PyErr_SetString(PyExc_RuntimeError,
 126                          "method.__self__ not accessible in restricted mode");
 127                         return NULL;
 128                 }
 129                 self = m->m_self;
 130                 if (self == NULL)
 131                         self = Py_None;
 132                 Py_INCREF(self);
 133                 return self;
 134         }
 135         if (strcmp(name, "__members__") == 0) {
 136                 return Py_BuildValue("[sss]",
 137                                      "__doc__", "__name__", "__self__");
 138         }
 139         PyErr_SetString(PyExc_AttributeError, name);
 140         return NULL;
 141 }
 142
 143 static PyObject *
 144 meth_repr(m)
 145         PyCFunctionObject *m;
 146 {
 147         char buf[200];
 148         if (m->m_self == NULL)
 149                 sprintf(buf, "<built-in function %.80s>", m->m_ml->ml_name);
 150         else
 151                 sprintf(buf,
 152                         "<built-in method %.80s of %.80s object at %lx>",
 153                         m->m_ml->ml_name, m->m_self->ob_type->tp_name,
 154                         (long)m->m_self);
 155         return PyString_FromString(buf);
 156 }
 157
 158 static int
 159 meth_compare(a, b)
 160         PyCFunctionObject *a, *b;
 161 {
 162         if (a->m_self != b->m_self)
 163                 return (a->m_self < b->m_self) ? -1 : 1;
 164         if (a->m_ml->ml_meth == b->m_ml->ml_meth)
 165                 return 0;
 166         if (strcmp(a->m_ml->ml_name, b->m_ml->ml_name) < 0)
 167                 return -1;
 168         else
 169                 return 1;
 170 }
 171
 172 static long
 173 meth_hash(a)
 174         PyCFunctionObject *a;
 175 {
 176         long x;
 177         if (a->m_self == NULL)
 178                 x = 0;
 179         else {
 180                 x = PyObject_Hash(a->m_self);
 181                 if (x == -1)
 182                         return -1;
 183         }
 184         return x ^ (long) a->m_ml->ml_meth;
 185 }
 186
 187 PyTypeObject PyCFunction_Type = {
 188         PyObject_HEAD_INIT(&PyType_Type)
 189         0,
 190         "builtin_function_or_method",
 191         sizeof(PyCFunctionObject),
 192         0,
 193         (destructor)meth_dealloc, /*tp_dealloc*/
 194         0,              /*tp_print*/
 195         (getattrfunc)meth_getattr, /*tp_getattr*/
 196         0,              /*tp_setattr*/
 197         (cmpfunc)meth_compare, /*tp_compare*/
 198         (reprfunc)meth_repr, /*tp_repr*/
 199         0,              /*tp_as_number*/
 200         0,              /*tp_as_sequence*/
 201         0,              /*tp_as_mapping*/
 202         (hashfunc)meth_hash, /*tp_hash*/
 203 };
 204
 205 /* List all methods in a chain -- helper for findmethodinchain */
 206
 207 static PyObject *
 208 listmethodchain(chain)
 209         PyMethodChain *chain;
 210 {
 211         PyMethodChain *c;
 212         PyMethodDef *ml;
 213         int i, n;
 214         PyObject *v;
 215
 216         n = 0;
 217         for (c = chain; c != NULL; c = c->link) {
 218                 for (ml = c->methods; ml->ml_name != NULL; ml++)
 219                         n++;
 220         }
 221         v = PyList_New(n);
 222         if (v == NULL)
 223                 return NULL;
 224         i = 0;
 225         for (c = chain; c != NULL; c = c->link) {
 226                 for (ml = c->methods; ml->ml_name != NULL; ml++) {
 227                         PyList_SetItem(v, i, PyString_FromString(ml->ml_name));
 228                         i++;
 229                 }
 230         }
 231         if (PyErr_Occurred()) {
 232                 Py_DECREF(v);
 233                 return NULL;
 234         }
 235         PyList_Sort(v);
 236         return v;
 237 }
 238
 239 /* Find a method in a method chain */
 240
 241 PyObject *
 242 Py_FindMethodInChain(chain, self, name)
 243         PyMethodChain *chain;
 244         PyObject *self;
 245         char *name;
 246 {
 247         if (name[0] == '_' && name[1] == '_') {
 248                 if (strcmp(name, "__methods__") == 0)
 249                         return listmethodchain(chain);
 250                 if (strcmp(name, "__doc__") == 0) {
 251                         char *doc = self->ob_type->tp_doc;
 252                         if (doc != NULL)
 253                                 return PyString_FromString(doc);
 254                 }
 255         }
 256         while (chain != NULL) {
 257                 PyMethodDef *ml = chain->methods;
 258                 for (; ml->ml_name != NULL; ml++) {
 259                         if (name[0] == ml->ml_name[0] &&
 260                             strcmp(name+1, ml->ml_name+1) == 0)
 261                                 return PyCFunction_New(ml, self);
 262                 }
 263                 chain = chain->link;
 264         }
 265         PyErr_SetString(PyExc_AttributeError, name);
 266         return NULL;
 267 }
 268
 269 /* Find a method in a single method list */
 270
 271 PyObject *
 272 Py_FindMethod(methods, self, name)
 273         PyMethodDef *methods;
 274         PyObject *self;
 275         char *name;
 276 {
 277         PyMethodChain chain;
 278         chain.methods = methods;
 279         chain.link = NULL;
 280         return Py_FindMethodInChain(&chain, self, name);
 281 }
 282
 283 /* Clear out the free list */
 284
 285 void
 286 PyCFunction_Fini()
 287 {
 288         while (free_list) {
 289                 PyCFunctionObject *v = free_list;
 290                 free_list = (PyCFunctionObject *)(v->m_self);
 291                 PyMem_DEL(v);
 292         }
 293 }