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

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