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 static PyTypeObject atom_pytype;
  43
  44 typedef struct entry {
  45   assoc_base _b;
  46   PyObject *a;
  47 } entry;
  48
  49 /*----- Static variables --------------------------------------------------*/
  50
  51 static assoc_table obarray;
  52
  53 /*----- Main code ---------------------------------------------------------*/
  54
  55 PyObject *atom_pywrap(atom *a)
  56 {
  57   entry *e;
  58   unsigned f = 0;
  59
  60   e = assoc_find(&obarray, a, sizeof(entry), &f);
  61   if (!f) {
  62     atom_pyobj *ao = PyObject_NEW(atom_pyobj, &atom_pytype);
  63     ao->a = a;
  64     e->a = (PyObject *)ao;
  65   }
  66   RETURN_OBJ(e->a);
  67 }
  68
  69 PyObject *atom_pyintern(PyObject *x)
  70 {
  71   atom *a;
  72   const void *p;
  73   int n;
  74
  75   if (ATOM_PYCHECK(x))
  76     RETURN_OBJ(x);
  77   if (x == Py_None)
  78     a = atom_gensym(ATOM_GLOBAL);
  79   else {
  80     if (PyObject_AsReadBuffer(x, &p, &n)) return (0);
  81     a = atom_nintern(ATOM_GLOBAL, p, n);
  82   }
  83   return (atom_pywrap(a));
  84 }
  85
  86 static void atom_pydealloc(PyObject *me)
  87   { fprintf(stderr, "ouch!  freeing atom\n"); abort();  }
  88
  89 static PyObject *atom_pynew(PyTypeObject *ty, PyObject *arg, PyObject *kw)
  90 {
  91   PyObject *name;
  92   static char *kwlist[] = { "name", 0 };
  93
  94   if (!PyArg_ParseTupleAndKeywords(arg, kw, "O:new", kwlist, &name))
  95     return (0);
  96   return (atom_pyintern(name));
  97 }
  98
  99 static PyObject *aget_name(PyObject *me, void *hunoz)
 100 {
 101   return (PyString_FromStringAndSize(ATOM_NAME(ATOM_A(me)),
 102                                      ATOM_LEN(ATOM_A(me))));
 103 }
 104
 105 static PyObject *aget_internedp(PyObject *me, void *hunoz)
 106 {
 107   PyObject *rc = (ATOM_A(me)->f & ATOMF_GENSYM) ? Py_False : Py_True;
 108   RETURN_OBJ(rc);
 109 }
 110
 111 static PyGetSetDef atom_pygetset[] = {
 112 #define GETSETNAME(op, name) a##op##_##name
 113   GET   (name,                  "A.name -> NAME")
 114   GET   (internedp,             "A.internedp -> BOOL")
 115 #undef GETSETNAME
 116   { 0 }
 117 };
 118
 119 static PyObject *atom_pyrichcompare(PyObject *x, PyObject *y, int op)
 120 {
 121   PyObject *rc = 0;
 122
 123   switch (op) {
 124     case Py_EQ: rc = (x == y) ? Py_True : Py_False; break;
 125     case Py_NE: rc = (x != y) ? Py_True : Py_False; break;
 126     default:
 127       PyErr_SetString(PyExc_TypeError, "atoms are unordered");
 128       return (0);
 129   }
 130   RETURN_OBJ(rc);
 131 }
 132
 133 static PyObject *atom_pyrepr(PyObject *me)
 134 {
 135   PyObject *s, *sr = 0;
 136   PyObject *rc = 0;
 137   char *p;
 138   int n;
 139   dstr d = DSTR_INIT;
 140
 141   if ((s = aget_name(me, 0)) == 0 ||
 142       (sr = PyObject_Repr(s)) == 0 ||
 143       PyString_AsStringAndSize(sr, &p, &n))
 144     goto done;
 145   dstr_puts(&d, "Atom(");
 146   dstr_putm(&d, p, n);
 147   dstr_puts(&d, ")");
 148   rc = PyString_FromStringAndSize(d.buf, d.len);
 149 done:
 150   Py_XDECREF(s);
 151   Py_XDECREF(sr);
 152   dstr_destroy(&d);
 153   return (rc);
 154 }
 155
 156 static long atom_pyhash(PyObject *me)
 157   { long h = ATOM_HASH(ATOM_A(me)); if (h == -1) h = -2; return (h); }
 158
 159 static PyTypeObject atom_pytype = {
 160   PyObject_HEAD_INIT(0) 0,              /* Header */
 161   "atom.Atom",                          /* @tp_name@ */
 162   sizeof(atom_pyobj),                   /* @tp_basicsize@ */
 163   0,                                    /* @tp_itemsize@ */
 164
 165   atom_pydealloc,                       /* @tp_dealloc@ */
 166   0,                                    /* @tp_print@ */
 167   0,                                    /* @tp_getattr@ */
 168   0,                                    /* @tp_setattr@ */
 169   0,                                    /* @tp_compare@ */
 170   atom_pyrepr,                          /* @tp_repr@ */
 171   0,                                    /* @tp_as_number@ */
 172   0,                                    /* @tp_as_sequence@ */
 173   0,                                    /* @tp_as_mapping@ */
 174   atom_pyhash,                          /* @tp_hash@ */
 175   0,                                    /* @tp_call@ */
 176   atom_pyrepr,                          /* @tp_str@ */
 177   0,                                    /* @tp_getattro@ */
 178   0,                                    /* @tp_setattro@ */
 179   0,                                    /* @tp_as_buffer@ */
 180   Py_TPFLAGS_DEFAULT,                   /* @tp_flags@ */
 181
 182   /* @tp_doc@ */
 183 "Atom.",
 184
 185   0,                                    /* @tp_traverse@ */
 186   0,                                    /* @tp_clear@ */
 187   atom_pyrichcompare,                   /* @tp_richcompare@ */
 188   0,                                    /* @tp_weaklistoffset@ */
 189   0,                                    /* @tp_iter@ */
 190   0,                                    /* @tp_iternexr@ */
 191   0,                                    /* @tp_methods@ */
 192   0,                                    /* @tp_members@ */
 193   atom_pygetset,                        /* @tp_getset@ */
 194   0,                                    /* @tp_base@ */
 195   0,                                    /* @tp_dict@ */
 196   0,                                    /* @tp_descr_get@ */
 197   0,                                    /* @tp_descr_set@ */
 198   0,                                    /* @tp_dictoffset@ */
 199   0,                                    /* @tp_init@ */
 200   PyType_GenericAlloc,                  /* @tp_alloc@ */
 201   atom_pynew,                           /* @tp_new@ */
 202   0,                                    /* @tp_free@ */
 203   0                                     /* @tp_is_gc@ */
 204 };
 205
 206 PyObject *atom_pystartup(void)
 207 {
 208   assoc_create(&obarray);
 209   PyType_Ready(&atom_pytype);
 210   return ((PyObject *)&atom_pytype);
 211 }
 212
 213 /*----- That's all, folks -------------------------------------------------*/