Objects/funcobject.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 /* Function object implementation */
  33
  34 #include "Python.h"
  35 #include "compile.h"
  36 #include "structmember.h"
  37
  38 PyObject *
  39 PyFunction_New(code, globals)
  40         PyObject *code;
  41         PyObject *globals;
  42 {
  43         PyFunctionObject *op = PyObject_NEW(PyFunctionObject,
  44                                             &PyFunction_Type);
  45         if (op != NULL) {
  46                 PyObject *doc;
  47                 PyObject *consts;
  48                 Py_INCREF(code);
  49                 op->func_code = code;
  50                 Py_INCREF(globals);
  51                 op->func_globals = globals;
  52                 op->func_name = ((PyCodeObject *)code)->co_name;
  53                 Py_INCREF(op->func_name);
  54                 op->func_defaults = NULL; /* No default arguments */
  55                 consts = ((PyCodeObject *)code)->co_consts;
  56                 if (PyTuple_Size(consts) >= 1) {
  57                         doc = PyTuple_GetItem(consts, 0);
  58                         if (!PyString_Check(doc))
  59                                 doc = Py_None;
  60                 }
  61                 else
  62                         doc = Py_None;
  63                 Py_INCREF(doc);
  64                 op->func_doc = doc;
  65         }
  66         return (PyObject *)op;
  67 }
  68
  69 PyObject *
  70 PyFunction_GetCode(op)
  71         PyObject *op;
  72 {
  73         if (!PyFunction_Check(op)) {
  74                 PyErr_BadInternalCall();
  75                 return NULL;
  76         }
  77         return ((PyFunctionObject *) op) -> func_code;
  78 }
  79
  80 PyObject *
  81 PyFunction_GetGlobals(op)
  82         PyObject *op;
  83 {
  84         if (!PyFunction_Check(op)) {
  85                 PyErr_BadInternalCall();
  86                 return NULL;
  87         }
  88         return ((PyFunctionObject *) op) -> func_globals;
  89 }
  90
  91 PyObject *
  92 PyFunction_GetDefaults(op)
  93         PyObject *op;
  94 {
  95         if (!PyFunction_Check(op)) {
  96                 PyErr_BadInternalCall();
  97                 return NULL;
  98         }
  99         return ((PyFunctionObject *) op) -> func_defaults;
 100 }
 101
 102 int
 103 PyFunction_SetDefaults(op, defaults)
 104         PyObject *op;
 105         PyObject *defaults;
 106 {
 107         if (!PyFunction_Check(op)) {
 108                 PyErr_BadInternalCall();
 109                 return -1;
 110         }
 111         if (defaults == Py_None)
 112                 defaults = NULL;
 113         else if (PyTuple_Check(defaults)) {
 114                 Py_XINCREF(defaults);
 115         }
 116         else {
 117                 PyErr_SetString(PyExc_SystemError, "non-tuple default args");
 118                 return -1;
 119         }
 120         Py_XDECREF(((PyFunctionObject *) op) -> func_defaults);
 121         ((PyFunctionObject *) op) -> func_defaults = defaults;
 122         return 0;
 123 }
 124
 125 /* Methods */
 126
 127 #define OFF(x) offsetof(PyFunctionObject, x)
 128
 129 static struct memberlist func_memberlist[] = {
 130         {"func_code",   T_OBJECT,       OFF(func_code)},
 131         {"func_globals",T_OBJECT,       OFF(func_globals),      READONLY},
 132         {"func_name",   T_OBJECT,       OFF(func_name),         READONLY},
 133         {"__name__",    T_OBJECT,       OFF(func_name),         READONLY},
 134         {"func_defaults",T_OBJECT,      OFF(func_defaults)},
 135         {"func_doc",    T_OBJECT,       OFF(func_doc)},
 136         {"__doc__",     T_OBJECT,       OFF(func_doc)},
 137         {NULL}  /* Sentinel */
 138 };
 139
 140 static PyObject *
 141 func_getattr(op, name)
 142         PyFunctionObject *op;
 143         char *name;
 144 {
 145         if (name[0] != '_' && PyEval_GetRestricted()) {
 146                 PyErr_SetString(PyExc_RuntimeError,
 147                   "function attributes not accessible in restricted mode");
 148                 return NULL;
 149         }
 150         return PyMember_Get((char *)op, func_memberlist, name);
 151 }
 152
 153 static int
 154 func_setattr(op, name, value)
 155         PyFunctionObject *op;
 156         char *name;
 157         PyObject *value;
 158 {
 159         if (PyEval_GetRestricted()) {
 160                 PyErr_SetString(PyExc_RuntimeError,
 161                   "function attributes not settable in restricted mode");
 162                 return -1;
 163         }
 164         if (strcmp(name, "func_code") == 0) {
 165                 if (value == NULL || !PyCode_Check(value)) {
 166                         PyErr_SetString(
 167                                 PyExc_TypeError,
 168                                 "func_code must be set to a code object");
 169                         return -1;
 170                 }
 171         }
 172         else if (strcmp(name, "func_defaults") == 0) {
 173                 if (value != Py_None && !PyTuple_Check(value)) {
 174                         PyErr_SetString(
 175                                 PyExc_TypeError,
 176                                 "func_defaults must be set to a tuple object");
 177                         return -1;
 178                 }
 179                 if (value == Py_None)
 180                         value = NULL;
 181         }
 182         return PyMember_Set((char *)op, func_memberlist, name, value);
 183 }
 184
 185 static void
 186 func_dealloc(op)
 187         PyFunctionObject *op;
 188 {
 189         Py_DECREF(op->func_code);
 190         Py_DECREF(op->func_globals);
 191         Py_DECREF(op->func_name);
 192         Py_XDECREF(op->func_defaults);
 193         Py_XDECREF(op->func_doc);
 194         PyMem_DEL(op);
 195 }
 196
 197 static PyObject*
 198 func_repr(op)
 199         PyFunctionObject *op;
 200 {
 201         char buf[140];
 202         if (op->func_name == Py_None)
 203                 sprintf(buf, "<anonymous function at %lx>", (long)op);
 204         else
 205                 sprintf(buf, "<function %.100s at %lx>",
 206                         PyString_AsString(op->func_name),
 207                         (long)op);
 208         return PyString_FromString(buf);
 209 }
 210
 211 static int
 212 func_compare(f, g)
 213         PyFunctionObject *f, *g;
 214 {
 215         int c;
 216         if (f->func_globals != g->func_globals)
 217                 return (f->func_globals < g->func_globals) ? -1 : 1;
 218         if (f->func_defaults != g->func_defaults) {
 219                 if (f->func_defaults == NULL)
 220                         return -1;
 221                 if (g->func_defaults == NULL)
 222                         return 1;
 223                 c = PyObject_Compare(f->func_defaults, g->func_defaults);
 224                 if (c != 0)
 225                         return c;
 226         }
 227         return PyObject_Compare(f->func_code, g->func_code);
 228 }
 229
 230 static long
 231 func_hash(f)
 232         PyFunctionObject *f;
 233 {
 234         long h;
 235         h = PyObject_Hash(f->func_code);
 236         if (h == -1) return h;
 237         h = h ^ (long)f->func_globals;
 238         if (h == -1) h = -2;
 239         return h;
 240 }
 241
 242 PyTypeObject PyFunction_Type = {
 243         PyObject_HEAD_INIT(&PyType_Type)
 244         0,
 245         "function",
 246         sizeof(PyFunctionObject),
 247         0,
 248         (destructor)func_dealloc, /*tp_dealloc*/
 249         0,              /*tp_print*/
 250         (getattrfunc)func_getattr, /*tp_getattr*/
 251         (setattrfunc)func_setattr, /*tp_setattr*/
 252         (cmpfunc)func_compare, /*tp_compare*/
 253         (reprfunc)func_repr, /*tp_repr*/
 254         0,              /*tp_as_number*/
 255         0,              /*tp_as_sequence*/
 256         0,              /*tp_as_mapping*/
 257         (hashfunc)func_hash, /*tp_hash*/
 258 };