chiark - git - mdw - catacomb-python/blob - bytestring.c

   1 /* -*-c-*-
   2  *
   3  * Byte strings
   4  *
   5  * (c) 2004 Straylight/Edgeware
   6  */
   7
   8 /*----- Licensing notice --------------------------------------------------*
   9  *
  10  * This file is part of the Python interface to Catacomb.
  11  *
  12  * Catacomb/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  * Catacomb/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 Catacomb/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 "catacomb-python.h"
  30
  31 /*----- Main code ---------------------------------------------------------*/
  32
  33 PyTypeObject *bytestring_pytype;
  34
  35 static PyObject *dowrap(PyTypeObject *ty, const void *p, size_t n)
  36 {
  37   PyStringObject *x = (PyStringObject *)ty->tp_alloc(ty, n);
  38   if (p) memcpy(x->ob_sval, p, n);
  39   x->ob_sval[n] = 0;
  40 #if defined(CACHE_HASH) || PY_VERSION_HEX >= 0x02030000
  41   x->ob_shash = -1;
  42 #endif
  43   x->ob_sstate = SSTATE_NOT_INTERNED;
  44   return ((PyObject *)x);
  45 }
  46
  47 PyObject *bytestring_pywrap(const void *p, size_t n)
  48   { return (dowrap(bytestring_pytype, p, n)); }
  49
  50 PyObject *bytestring_pywrapbuf(buf *b)
  51   { return (dowrap(bytestring_pytype, BCUR(b), BLEFT(b))); }
  52
  53 static PyObject *bytestring_pynew(PyTypeObject *ty,
  54                                   PyObject *arg, PyObject *kw)
  55 {
  56   const char *p;
  57   Py_ssize_t n;
  58   static const char *const kwlist[] = { "data", 0 };
  59   if (!PyArg_ParseTupleAndKeywords(arg, kw, "s#:new", KWLIST, &p, &n))
  60     return (0);
  61   return (dowrap(ty, p, n));
  62 }
  63
  64 static PyObject *meth_ctstreq(PyObject *me, PyObject *arg)
  65 {
  66   char *p, *q;
  67   Py_ssize_t psz, qsz;
  68   if (!PyArg_ParseTuple(arg, "s#s#:ctstreq", &p, &psz, &q, &qsz))
  69     goto end;
  70   if (psz == qsz && ct_memeq(p, q, psz)) RETURN_TRUE;
  71   else RETURN_FALSE;
  72 end:
  73   return (0);
  74 }
  75
  76 static PyObject *meth__ByteString_zero(PyObject *me, PyObject *arg)
  77 {
  78   size_t sz;
  79   PyObject *rc = 0;
  80   if (!PyArg_ParseTuple(arg, "OO&:zero", &me, convszt, &sz)) goto end;
  81   rc = bytestring_pywrap(0, sz);
  82   memset(PyString_AS_STRING(rc), 0, sz);
  83 end:
  84   return (rc);
  85 }
  86
  87 static PyObject *bytestring_pyrichcompare(PyObject *me,
  88                                           PyObject *you, int op)
  89 {
  90   int b;
  91   void *mystr, *yourstr;
  92   Py_ssize_t mylen, yourlen, minlen;
  93
  94   if (!PyString_Check(me) || !PyString_Check(you)) RETURN_NOTIMPL;
  95   mystr = PyString_AS_STRING(me); mylen = PyString_GET_SIZE(me);
  96   yourstr = PyString_AS_STRING(you); yourlen = PyString_GET_SIZE(you);
  97
  98   switch (op) {
  99     case Py_EQ:
 100       b = mylen == yourlen && ct_memeq(mystr, yourstr, mylen);
 101       break;
 102     case Py_NE:
 103       b = mylen != yourlen || !ct_memeq(mystr, yourstr, mylen);
 104       break;
 105     default:
 106       minlen = mylen < yourlen ? mylen : yourlen;
 107       b = memcmp(mystr, yourstr, minlen);
 108       if (!b) b = mylen < yourlen ? -1 : mylen > yourlen ? +1 : 0;
 109       switch (op) {
 110         case Py_LT: b = b <  0; break;
 111         case Py_LE: b = b <= 0; break;
 112         case Py_GE: b = b >= 0; break;
 113         case Py_GT: b = b >  0; break;
 114         default: abort();
 115       }
 116   }
 117   if (b) RETURN_TRUE;
 118   else RETURN_FALSE;
 119 }
 120
 121 #define BINOP(name, op)                                                 \
 122   static PyObject *bytestring_py##name(PyObject *x, PyObject *y) {      \
 123     const void *xv, *yv;                                                \
 124     const unsigned char *xp, *yp;                                       \
 125     unsigned char *zp;                                                  \
 126     Py_ssize_t xsz, ysz;                                                \
 127     int i;                                                              \
 128     PyObject *rc = 0;                                                   \
 129     if (PyObject_AsReadBuffer(x, &xv, &xsz) ||                          \
 130         PyObject_AsReadBuffer(y, &yv, &ysz))                            \
 131       goto end;                                                         \
 132     if (xsz != ysz) VALERR("length mismatch");                          \
 133     rc = bytestring_pywrap(0, xsz);                                     \
 134     xp = xv; yp = yv; zp = (unsigned char *)PyString_AS_STRING(rc);     \
 135     for (i = xsz; i > 0; i--) *zp++ = *xp++ op *yp++;                   \
 136   end:                                                                  \
 137     return (rc);                                                        \
 138   }
 139 BINOP(and, &)
 140 BINOP(or, |)
 141 BINOP(xor, ^)
 142
 143 #define UNOP(name, op)                                                  \
 144   static PyObject *bytestring_py##name(PyObject *x) {                   \
 145     const void *xv;                                                     \
 146     const unsigned char *xp;                                            \
 147     unsigned char *zp;                                                  \
 148     Py_ssize_t xsz;                                                     \
 149     int i;                                                              \
 150     PyObject *rc = 0;                                                   \
 151     if (PyObject_AsReadBuffer(x, &xv, &xsz)) goto end;                  \
 152     rc = bytestring_pywrap(0, xsz);                                     \
 153     xp = xv; zp = (unsigned char *)PyString_AS_STRING(rc);              \
 154     for (i = xsz; i > 0; i--) *zp++ = op *xp++;                         \
 155   end:                                                                  \
 156     return (rc);                                                        \
 157   }
 158 UNOP(not, ~)
 159
 160 static PyNumberMethods bytestring_pynumber = {
 161   0,                                    /* @nb_add@ */
 162   0,                                    /* @nb_subtract@ */
 163   0,                                    /* @nb_multiply@ */
 164   0,                                    /* @nb_divide@ */
 165   0,                                    /* @nb_remainder@ */
 166   0,                                    /* @nb_divmod@ */
 167   0,                                    /* @nb_power@ */
 168   0,                                    /* @nb_negative@ */
 169   0,                                    /* @nb_positive@ */
 170   0,                                    /* @nb_absolute@ */
 171   0,                                    /* @nb_nonzero@ */
 172   bytestring_pynot,                     /* @nb_invert@ */
 173   0,                                    /* @nb_lshift@ */
 174   0,                                    /* @nb_rshift@ */
 175   bytestring_pyand,                     /* @nb_and@ */
 176   bytestring_pyxor,                     /* @nb_xor@ */
 177   bytestring_pyor,                      /* @nb_or@ */
 178   0,                                    /* @nb_coerce@ */
 179   0,                                    /* @nb_int@ */
 180   0,                                    /* @nb_long@ */
 181   0,                                    /* @nb_float@ */
 182   0,                                    /* @nb_oct@ */
 183   0,                                    /* @nb_hex@ */
 184 };
 185
 186 static PyBufferProcs bytestring_pybuffer;
 187
 188 static PyTypeObject bytestring_pytype_skel = {
 189   PyObject_HEAD_INIT(0) 0,              /* Header */
 190   "ByteString",                         /* @tp_name@ */
 191   0,                                    /* @tp_basicsize@ */
 192   0,                                    /* @tp_itemsize@ */
 193
 194   0,                                    /* @tp_dealloc@ */
 195   0,                                    /* @tp_print@ */
 196   0,                                    /* @tp_getattr@ */
 197   0,                                    /* @tp_setattr@ */
 198   0,                                    /* @tp_compare@ */
 199   0,                                    /* @tp_repr@ */
 200   &bytestring_pynumber,                 /* @tp_as_number@ */
 201   0,                                    /* @tp_as_sequence@ */
 202   0,                                    /* @tp_as_mapping@ */
 203   0,                                    /* @tp_hash@ */
 204   0,                                    /* @tp_call@ */
 205   0,                                    /* @tp_str@ */
 206   0,                                    /* @tp_getattro@ */
 207   0,                                    /* @tp_setattro@ */
 208   &bytestring_pybuffer,                 /* @tp_as_buffer@ */
 209   Py_TPFLAGS_DEFAULT |                  /* @tp_flags@ */
 210     Py_TPFLAGS_CHECKTYPES |
 211     Py_TPFLAGS_BASETYPE,
 212
 213   /* @tp_doc@ */
 214 "ByteString(STR): byte string class.",
 215
 216   0,                                    /* @tp_traverse@ */
 217   0,                                    /* @tp_clear@ */
 218   bytestring_pyrichcompare,             /* @tp_richcompare@ */
 219   0,                                    /* @tp_weaklistoffset@ */
 220   0,                                    /* @tp_iter@ */
 221   0,                                    /* @tp_iternext@ */
 222   0,                                    /* @tp_methods@ */
 223   0,                                    /* @tp_members@ */
 224   0,                                    /* @tp_getset@ */
 225   0,                                    /* @tp_base@ */
 226   0,                                    /* @tp_dict@ */
 227   0,                                    /* @tp_descr_get@ */
 228   0,                                    /* @tp_descr_set@ */
 229   0,                                    /* @tp_dictoffset@ */
 230   0,                                    /* @tp_init@ */
 231   PyType_GenericAlloc,                  /* @tp_alloc@ */
 232   bytestring_pynew,                     /* @tp_new@ */
 233   0,                                    /* @tp_free@ */
 234   0                                     /* @tp_is_gc@ */
 235 };
 236
 237 /*----- Initialization ----------------------------------------------------*/
 238
 239 static PyMethodDef methods[] = {
 240 #define METHNAME(func) meth_##func
 241   METH  (ctstreq,               "ctstreq(S, T) -> BOOL")
 242   METH  (_ByteString_zero,      "zero(N) -> 0000...00")
 243 #undef METHNAME
 244   { 0 }
 245 };
 246
 247 #define string_pytype &PyString_Type
 248 void bytestring_pyinit(void)
 249 {
 250   INITTYPE(bytestring, string);
 251   addmethods(methods);
 252 }
 253
 254 void bytestring_pyinsert(PyObject *mod)
 255 {
 256   INSERT("ByteString", bytestring_pytype);
 257 }
 258
 259 /*----- That's all, folks -------------------------------------------------*/