mdw@git.distorted.org.uk Git - mLib-python/blob - atom-base.c

   1 /* -*-c-*-
   2  *
   3  * $Id$
   4  *
   5  * Atom stuff
   6  *
   7  * (c) 2005 Straylight/Edgeware
   8  */
   9
  10 /*----- Licensing notice --------------------------------------------------*
  11  *
  12  * This file is part of the Python interface to mLib.
  13  *
  14  * mLib/Python is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2 of the License, or
  17  * (at your option) any later version.
  18  *
  19  * mLib/Python is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with mLib/Python; if not, write to the Free Software Foundation,
  26  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  27  */
  28
  29 /*----- Header files ------------------------------------------------------*/
  30
  31 #include <Python.h>
  32
  33 #include <mLib/atom.h>
  34 #include <mLib/assoc.h>
  35 #include <mLib/dstr.h>
  36
  37 #include "atom.h"
  38 #include "grim.h"
  39
  40 /*----- Data structures ---------------------------------------------------*/
  41
  42 typedef struct entry {
  43   assoc_base _b;
  44   PyObject *a;
  45 } entry;
  46
  47 /*----- Static variables --------------------------------------------------*/
  48
  49 static assoc_table obarray;
  50
  51 /*----- Main code ---------------------------------------------------------*/
  52
  53 PyObject *atom_pywrap(atom *a)
  54 {
  55   entry *e;
  56   unsigned f = 0;
  57
  58   e = assoc_find(&obarray, a, sizeof(entry), &f);
  59   if (!f) {
  60     atom_pyobj *ao = PyObject_NEW(atom_pyobj, &atom_pytype);
  61     ao->a = a;
  62     e->a = (PyObject *)ao;
  63   }
  64   RETURN_OBJ(e->a);
  65 }
  66
  67 PyObject *atom_pyintern(PyObject *x)
  68 {
  69   atom *a;
  70   const void *p;
  71   int n;
  72
  73   if (ATOM_PYCHECK(x))
  74     RETURN_OBJ(x);
  75   if (x == Py_None)
  76     a = atom_gensym(ATOM_GLOBAL);
  77   else {
  78     if (PyObject_AsReadBuffer(x, &p, &n)) return (0);
  79     a = atom_nintern(ATOM_GLOBAL, p, n);
  80   }
  81   return (atom_pywrap(a));
  82 }
  83
  84 static void atom_pydealloc(PyObject *me)
  85   { fprintf(stderr, "ouch!  freeing atom\n"); abort();  }
  86
  87 static PyObject *atom_pynew(PyTypeObject *ty, PyObject *arg, PyObject *kw)
  88 {
  89   PyObject *name;
  90   static char *kwlist[] = { "name", 0 };
  91
  92   if (!PyArg_ParseTupleAndKeywords(arg, kw, "O:new", kwlist, &name))
  93     return (0);
  94   return (atom_pyintern(name));
  95 }
  96
  97 static PyObject *aget_name(PyObject *me, void *hunoz)
  98 {
  99   return (PyString_FromStringAndSize(ATOM_NAME(ATOM_A(me)),
 100                                      ATOM_LEN(ATOM_A(me))));
 101 }
 102
 103 static PyObject *aget_internedp(PyObject *me, void *hunoz)
 104 {
 105   PyObject *rc = (ATOM_A(me)->f & ATOMF_GENSYM) ? Py_False : Py_True;
 106   RETURN_OBJ(rc);
 107 }
 108
 109 static PyGetSetDef atom_pygetset[] = {
 110 #define GETSETNAME(op, name) a##op##_##name
 111   GET   (name,                  "A.name -> NAME")
 112   GET   (internedp,             "A.internedp -> BOOL")
 113 #undef GETSETNAME
 114   { 0 }
 115 };
 116
 117 static PyObject *atom_pyrichcompare(PyObject *x, PyObject *y, int op)
 118 {
 119   PyObject *rc = 0;
 120
 121   switch (op) {
 122     case Py_EQ: rc = (x == y) ? Py_True : Py_False; break;
 123     case Py_NE: rc = (x != y) ? Py_True : Py_False; break;
 124     default:
 125       PyErr_SetString(PyExc_TypeError, "atoms are unordered");
 126       return (0);
 127   }
 128   RETURN_OBJ(rc);
 129 }
 130
 131 static PyObject *atom_pyrepr(PyObject *me)
 132 {
 133   PyObject *s, *sr = 0;
 134   PyObject *rc = 0;
 135   char *p;
 136   int n;
 137   dstr d = DSTR_INIT;
 138
 139   if ((s = aget_name(me, 0)) == 0 ||
 140       (sr = PyObject_Repr(s)) == 0 ||
 141       PyString_AsStringAndSize(sr, &p, &n))
 142     goto done;
 143   dstr_puts(&d, "Atom(");
 144   dstr_putm(&d, p, n);
 145   dstr_puts(&d, ")");
 146   rc = PyString_FromStringAndSize(d.buf, d.len);
 147 done:
 148   Py_XDECREF(s);
 149   Py_XDECREF(sr);
 150   dstr_destroy(&d);
 151   return (rc);
 152 }
 153
 154 static long atom_pyhash(PyObject *me)
 155   { long h = ATOM_HASH(ATOM_A(me)); if (h == -1) h = -2; return (h); }
 156
 157 PyTypeObject atom_pytype = {
 158   PyObject_HEAD_INIT(0) 0,              /* Header */
 159   "mLib.Atom",                          /* @tp_name@ */
 160   sizeof(atom_pyobj),                   /* @tp_basicsize@ */
 161   0,                                    /* @tp_itemsize@ */
 162
 163   atom_pydealloc,                       /* @tp_dealloc@ */
 164   0,                                    /* @tp_print@ */
 165   0,                                    /* @tp_getattr@ */
 166   0,                                    /* @tp_setattr@ */
 167   0,                                    /* @tp_compare@ */
 168   atom_pyrepr,                          /* @tp_repr@ */
 169   0,                                    /* @tp_as_number@ */
 170   0,                                    /* @tp_as_sequence@ */
 171   0,                                    /* @tp_as_mapping@ */
 172   atom_pyhash,                          /* @tp_hash@ */
 173   0,                                    /* @tp_call@ */
 174   atom_pyrepr,                          /* @tp_str@ */
 175   0,                                    /* @tp_getattro@ */
 176   0,                                    /* @tp_setattro@ */
 177   0,                                    /* @tp_as_buffer@ */
 178   Py_TPFLAGS_DEFAULT,                   /* @tp_flags@ */
 179
 180   /* @tp_doc@ */
 181 "Atom.",
 182
 183   0,                                    /* @tp_traverse@ */
 184   0,                                    /* @tp_clear@ */
 185   atom_pyrichcompare,                   /* @tp_richcompare@ */
 186   0,                                    /* @tp_weaklistoffset@ */
 187   0,                                    /* @tp_iter@ */
 188   0,                                    /* @tp_iternexr@ */
 189   0,                                    /* @tp_methods@ */
 190   0,                                    /* @tp_members@ */
 191   atom_pygetset,                        /* @tp_getset@ */
 192   0,                                    /* @tp_base@ */
 193   0,                                    /* @tp_dict@ */
 194   0,                                    /* @tp_descr_get@ */
 195   0,                                    /* @tp_descr_set@ */
 196   0,                                    /* @tp_dictoffset@ */
 197   0,                                    /* @tp_init@ */
 198   PyType_GenericAlloc,                  /* @tp_alloc@ */
 199   atom_pynew,                           /* @tp_new@ */
 200   0,                                    /* @tp_free@ */
 201   0                                     /* @tp_is_gc@ */
 202 };
 203
 204 void atom_pysetup(void)
 205   { assoc_create(&obarray); PyType_Ready(&atom_pytype); }
 206
 207 /*----- That's all, folks -------------------------------------------------*/