1 #include "Python.h" 2 #include "code.h" 3 #include "structmember.h" 4 5 #define NAME_CHARS \ 6 "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ_abcdefghijklmnopqrstuvwxyz" 7 8 /* all_name_chars(s): true iff all chars in s are valid NAME_CHARS */ 9 10 static int 11 all_name_chars(unsigned char *s) 12 { 13 static char ok_name_char[256]; 14 static unsigned char *name_chars = (unsigned char *)NAME_CHARS; 15 16 if (ok_name_char[*name_chars] == 0) { 17 unsigned char *p; 18 for (p = name_chars; *p; p++) 19 ok_name_char[*p] = 1; 20 } 21 while (*s) { 22 if (ok_name_char[*s++] == 0) 23 return 0; 24 } 25 return 1; 26 } 27 28 static void 29 intern_strings(PyObject *tuple) 30 { 31 Py_ssize_t i; 32 33 for (i = PyTuple_GET_SIZE(tuple); --i >= 0; ) { 34 PyObject *v = PyTuple_GET_ITEM(tuple, i); 35 if (v == NULL || !PyString_CheckExact(v)) { 36 Py_FatalError("non-string found in code slot"); 37 } 38 PyString_InternInPlace(&PyTuple_GET_ITEM(tuple, i)); 39 } 40 } 41 42 43 PyCodeObject * 44 PyCode_New(int argcount, int nlocals, int stacksize, int flags, 45 PyObject *code, PyObject *consts, PyObject *names, 46 PyObject *varnames, PyObject *freevars, PyObject *cellvars, 47 PyObject *filename, PyObject *name, int firstlineno, 48 PyObject *lnotab) 49 { 50 PyCodeObject *co; 51 Py_ssize_t i; 52 /* Check argument types */ 53 if (argcount < 0 || nlocals < 0 || 54 code == NULL || 55 consts == NULL || !PyTuple_Check(consts) || 56 names == NULL || !PyTuple_Check(names) || 57 varnames == NULL || !PyTuple_Check(varnames) || 58 freevars == NULL || !PyTuple_Check(freevars) || 59 cellvars == NULL || !PyTuple_Check(cellvars) || 60 name == NULL || !PyString_Check(name) || 61 filename == NULL || !PyString_Check(filename) || 62 lnotab == NULL || !PyString_Check(lnotab) || 63 !PyObject_CheckReadBuffer(code)) { 64 PyErr_BadInternalCall(); 65 return NULL; 66 } 67 intern_strings(names); 68 intern_strings(varnames); 69 intern_strings(freevars); 70 intern_strings(cellvars); 71 /* Intern selected string constants */ 72 for (i = PyTuple_Size(consts); --i >= 0; ) { 73 PyObject *v = PyTuple_GetItem(consts, i); 74 if (!PyString_Check(v)) 75 continue; 76 if (!all_name_chars((unsigned char *)PyString_AS_STRING(v))) 77 continue; 78 PyString_InternInPlace(&PyTuple_GET_ITEM(consts, i)); 79 } 80 co = PyObject_NEW(PyCodeObject, &PyCode_Type); 81 if (co != NULL) { 82 co->co_argcount = argcount; 83 co->co_nlocals = nlocals; 84 co->co_stacksize = stacksize; 85 co->co_flags = flags; 86 Py_INCREF(code); 87 co->co_code = code; 88 Py_INCREF(consts); 89 co->co_consts = consts; 90 Py_INCREF(names); 91 co->co_names = names; 92 Py_INCREF(varnames); 93 co->co_varnames = varnames; 94 Py_INCREF(freevars); 95 co->co_freevars = freevars; 96 Py_INCREF(cellvars); 97 co->co_cellvars = cellvars; 98 Py_INCREF(filename); 99 co->co_filename = filename; 100 Py_INCREF(name); 101 co->co_name = name; 102 co->co_firstlineno = firstlineno; 103 Py_INCREF(lnotab); 104 co->co_lnotab = lnotab; 105 co->co_zombieframe = NULL; 106 co->co_weakreflist = NULL; 107 } 108 return co; 109 } 110 111 PyCodeObject * 112 PyCode_NewEmpty(const char *filename, const char *funcname, int firstlineno) 113 { 114 static PyObject *emptystring = NULL; 115 static PyObject *nulltuple = NULL; 116 PyObject *filename_ob = NULL; 117 PyObject *funcname_ob = NULL; 118 PyCodeObject *result = NULL; 119 if (emptystring == NULL) { 120 emptystring = PyString_FromString(""); 121 if (emptystring == NULL) 122 goto failed; 123 } 124 if (nulltuple == NULL) { 125 nulltuple = PyTuple_New(0); 126 if (nulltuple == NULL) 127 goto failed; 128 } 129 funcname_ob = PyString_FromString(funcname); 130 if (funcname_ob == NULL) 131 goto failed; 132 filename_ob = PyString_FromString(filename); 133 if (filename_ob == NULL) 134 goto failed; 135 136 result = PyCode_New(0, /* argcount */ 137 0, /* nlocals */ 138 0, /* stacksize */ 139 0, /* flags */ 140 emptystring, /* code */ 141 nulltuple, /* consts */ 142 nulltuple, /* names */ 143 nulltuple, /* varnames */ 144 nulltuple, /* freevars */ 145 nulltuple, /* cellvars */ 146 filename_ob, /* filename */ 147 funcname_ob, /* name */ 148 firstlineno, /* firstlineno */ 149 emptystring /* lnotab */ 150 ); 151 152 failed: 153 Py_XDECREF(funcname_ob); 154 Py_XDECREF(filename_ob); 155 return result; 156 } 157 158 #define OFF(x) offsetof(PyCodeObject, x) 159 160 static PyMemberDef code_memberlist[] = { 161 {"co_argcount", T_INT, OFF(co_argcount), READONLY}, 162 {"co_nlocals", T_INT, OFF(co_nlocals), READONLY}, 163 {"co_stacksize",T_INT, OFF(co_stacksize), READONLY}, 164 {"co_flags", T_INT, OFF(co_flags), READONLY}, 165 {"co_code", T_OBJECT, OFF(co_code), READONLY}, 166 {"co_consts", T_OBJECT, OFF(co_consts), READONLY}, 167 {"co_names", T_OBJECT, OFF(co_names), READONLY}, 168 {"co_varnames", T_OBJECT, OFF(co_varnames), READONLY}, 169 {"co_freevars", T_OBJECT, OFF(co_freevars), READONLY}, 170 {"co_cellvars", T_OBJECT, OFF(co_cellvars), READONLY}, 171 {"co_filename", T_OBJECT, OFF(co_filename), READONLY}, 172 {"co_name", T_OBJECT, OFF(co_name), READONLY}, 173 {"co_firstlineno", T_INT, OFF(co_firstlineno), READONLY}, 174 {"co_lnotab", T_OBJECT, OFF(co_lnotab), READONLY}, 175 {NULL} /* Sentinel */ 176 }; 177 178 /* Helper for code_new: return a shallow copy of a tuple that is 179 guaranteed to contain exact strings, by converting string subclasses 180 to exact strings and complaining if a non-string is found. */ 181 static PyObject* 182 validate_and_copy_tuple(PyObject *tup) 183 { 184 PyObject *newtuple; 185 PyObject *item; 186 Py_ssize_t i, len; 187 188 len = PyTuple_GET_SIZE(tup); 189 newtuple = PyTuple_New(len); 190 if (newtuple == NULL) 191 return NULL; 192 193 for (i = 0; i < len; i++) { 194 item = PyTuple_GET_ITEM(tup, i); 195 if (PyString_CheckExact(item)) { 196 Py_INCREF(item); 197 } 198 else if (!PyString_Check(item)) { 199 PyErr_Format( 200 PyExc_TypeError, 201 "name tuples must contain only " 202 "strings, not '%.500s'", 203 item->ob_type->tp_name); 204 Py_DECREF(newtuple); 205 return NULL; 206 } 207 else { 208 item = PyString_FromStringAndSize( 209 PyString_AS_STRING(item), 210 PyString_GET_SIZE(item)); 211 if (item == NULL) { 212 Py_DECREF(newtuple); 213 return NULL; 214 } 215 } 216 PyTuple_SET_ITEM(newtuple, i, item); 217 } 218 219 return newtuple; 220 } 221 222 PyDoc_STRVAR(code_doc, 223 "code(argcount, nlocals, stacksize, flags, codestring, constants, names,\n\ 224 varnames, filename, name, firstlineno, lnotab[, freevars[, cellvars]])\n\ 225 \n\ 226 Create a code object. Not for the faint of heart."); 227 228 static PyObject * 229 code_new(PyTypeObject *type, PyObject *args, PyObject *kw) 230 { 231 int argcount; 232 int nlocals; 233 int stacksize; 234 int flags; 235 PyObject *co = NULL; 236 PyObject *code; 237 PyObject *consts; 238 PyObject *names, *ournames = NULL; 239 PyObject *varnames, *ourvarnames = NULL; 240 PyObject *freevars = NULL, *ourfreevars = NULL; 241 PyObject *cellvars = NULL, *ourcellvars = NULL; 242 PyObject *filename; 243 PyObject *name; 244 int firstlineno; 245 PyObject *lnotab; 246 247 if (!PyArg_ParseTuple(args, "iiiiSO!O!O!SSiS|O!O!:code", 248 &argcount, &nlocals, &stacksize, &flags, 249 &code, 250 &PyTuple_Type, &consts, 251 &PyTuple_Type, &names, 252 &PyTuple_Type, &varnames, 253 &filename, &name, 254 &firstlineno, &lnotab, 255 &PyTuple_Type, &freevars, 256 &PyTuple_Type, &cellvars)) 257 return NULL; 258 259 if (argcount < 0) { 260 PyErr_SetString( 261 PyExc_ValueError, 262 "code: argcount must not be negative"); 263 goto cleanup; 264 } 265 266 if (nlocals < 0) { 267 PyErr_SetString( 268 PyExc_ValueError, 269 "code: nlocals must not be negative"); 270 goto cleanup; 271 } 272 273 ournames = validate_and_copy_tuple(names); 274 if (ournames == NULL) 275 goto cleanup; 276 ourvarnames = validate_and_copy_tuple(varnames); 277 if (ourvarnames == NULL) 278 goto cleanup; 279 if (freevars) 280 ourfreevars = validate_and_copy_tuple(freevars); 281 else 282 ourfreevars = PyTuple_New(0); 283 if (ourfreevars == NULL) 284 goto cleanup; 285 if (cellvars) 286 ourcellvars = validate_and_copy_tuple(cellvars); 287 else 288 ourcellvars = PyTuple_New(0); 289 if (ourcellvars == NULL) 290 goto cleanup; 291 292 co = (PyObject *)PyCode_New(argcount, nlocals, stacksize, flags, 293 code, consts, ournames, ourvarnames, 294 ourfreevars, ourcellvars, filename, 295 name, firstlineno, lnotab); 296 cleanup: 297 Py_XDECREF(ournames); 298 Py_XDECREF(ourvarnames); 299 Py_XDECREF(ourfreevars); 300 Py_XDECREF(ourcellvars); 301 return co; 302 } 303 304 static void 305 code_dealloc(PyCodeObject *co) 306 { 307 Py_XDECREF(co->co_code); 308 Py_XDECREF(co->co_consts); 309 Py_XDECREF(co->co_names); 310 Py_XDECREF(co->co_varnames); 311 Py_XDECREF(co->co_freevars); 312 Py_XDECREF(co->co_cellvars); 313 Py_XDECREF(co->co_filename); 314 Py_XDECREF(co->co_name); 315 Py_XDECREF(co->co_lnotab); 316 if (co->co_zombieframe != NULL) 317 PyObject_GC_Del(co->co_zombieframe); 318 if (co->co_weakreflist != NULL) 319 PyObject_ClearWeakRefs((PyObject*)co); 320 PyObject_DEL(co); 321 } 322 323 static PyObject * 324 code_repr(PyCodeObject *co) 325 { 326 char buf[500]; 327 int lineno = -1; 328 char *filename = "???"; 329 char *name = "???"; 330 331 if (co->co_firstlineno != 0) 332 lineno = co->co_firstlineno; 333 if (co->co_filename && PyString_Check(co->co_filename)) 334 filename = PyString_AS_STRING(co->co_filename); 335 if (co->co_name && PyString_Check(co->co_name)) 336 name = PyString_AS_STRING(co->co_name); 337 PyOS_snprintf(buf, sizeof(buf), 338 "<code object %.100s at %p, file \"%.300s\", line %d>", 339 name, co, filename, lineno); 340 return PyString_FromString(buf); 341 } 342 343 static int 344 code_compare(PyCodeObject *co, PyCodeObject *cp) 345 { 346 int cmp; 347 cmp = PyObject_Compare(co->co_name, cp->co_name); 348 if (cmp) return cmp; 349 cmp = co->co_argcount - cp->co_argcount; 350 if (cmp) goto normalize; 351 cmp = co->co_nlocals - cp->co_nlocals; 352 if (cmp) goto normalize; 353 cmp = co->co_flags - cp->co_flags; 354 if (cmp) goto normalize; 355 cmp = co->co_firstlineno - cp->co_firstlineno; 356 if (cmp) goto normalize; 357 cmp = PyObject_Compare(co->co_code, cp->co_code); 358 if (cmp) return cmp; 359 cmp = PyObject_Compare(co->co_consts, cp->co_consts); 360 if (cmp) return cmp; 361 cmp = PyObject_Compare(co->co_names, cp->co_names); 362 if (cmp) return cmp; 363 cmp = PyObject_Compare(co->co_varnames, cp->co_varnames); 364 if (cmp) return cmp; 365 cmp = PyObject_Compare(co->co_freevars, cp->co_freevars); 366 if (cmp) return cmp; 367 cmp = PyObject_Compare(co->co_cellvars, cp->co_cellvars); 368 return cmp; 369 370 normalize: 371 if (cmp > 0) 372 return 1; 373 else if (cmp < 0) 374 return -1; 375 else 376 return 0; 377 } 378 379 static PyObject * 380 code_richcompare(PyObject *self, PyObject *other, int op) 381 { 382 PyCodeObject *co, *cp; 383 int eq; 384 PyObject *res; 385 386 if ((op != Py_EQ && op != Py_NE) || 387 !PyCode_Check(self) || 388 !PyCode_Check(other)) { 389 390 /* Py3K warning if types are not equal and comparison 391 isn't == or != */ 392 if (PyErr_WarnPy3k("code inequality comparisons not supported " 393 "in 3.x", 1) < 0) { 394 return NULL; 395 } 396 397 Py_INCREF(Py_NotImplemented); 398 return Py_NotImplemented; 399 } 400 401 co = (PyCodeObject *)self; 402 cp = (PyCodeObject *)other; 403 404 eq = PyObject_RichCompareBool(co->co_name, cp->co_name, Py_EQ); 405 if (eq <= 0) goto unequal; 406 eq = co->co_argcount == cp->co_argcount; 407 if (!eq) goto unequal; 408 eq = co->co_nlocals == cp->co_nlocals; 409 if (!eq) goto unequal; 410 eq = co->co_flags == cp->co_flags; 411 if (!eq) goto unequal; 412 eq = co->co_firstlineno == cp->co_firstlineno; 413 if (!eq) goto unequal; 414 eq = PyObject_RichCompareBool(co->co_code, cp->co_code, Py_EQ); 415 if (eq <= 0) goto unequal; 416 eq = PyObject_RichCompareBool(co->co_consts, cp->co_consts, Py_EQ); 417 if (eq <= 0) goto unequal; 418 eq = PyObject_RichCompareBool(co->co_names, cp->co_names, Py_EQ); 419 if (eq <= 0) goto unequal; 420 eq = PyObject_RichCompareBool(co->co_varnames, cp->co_varnames, Py_EQ); 421 if (eq <= 0) goto unequal; 422 eq = PyObject_RichCompareBool(co->co_freevars, cp->co_freevars, Py_EQ); 423 if (eq <= 0) goto unequal; 424 eq = PyObject_RichCompareBool(co->co_cellvars, cp->co_cellvars, Py_EQ); 425 if (eq <= 0) goto unequal; 426 427 if (op == Py_EQ) 428 res = Py_True; 429 else 430 res = Py_False; 431 goto done; 432 433 unequal: 434 if (eq < 0) 435 return NULL; 436 if (op == Py_NE) 437 res = Py_True; 438 else 439 res = Py_False; 440 441 done: 442 Py_INCREF(res); 443 return res; 444 } 445 446 static long 447 code_hash(PyCodeObject *co) 448 { 449 long h, h0, h1, h2, h3, h4, h5, h6; 450 h0 = PyObject_Hash(co->co_name); 451 if (h0 == -1) return -1; 452 h1 = PyObject_Hash(co->co_code); 453 if (h1 == -1) return -1; 454 h2 = PyObject_Hash(co->co_consts); 455 if (h2 == -1) return -1; 456 h3 = PyObject_Hash(co->co_names); 457 if (h3 == -1) return -1; 458 h4 = PyObject_Hash(co->co_varnames); 459 if (h4 == -1) return -1; 460 h5 = PyObject_Hash(co->co_freevars); 461 if (h5 == -1) return -1; 462 h6 = PyObject_Hash(co->co_cellvars); 463 if (h6 == -1) return -1; 464 h = h0 ^ h1 ^ h2 ^ h3 ^ h4 ^ h5 ^ h6 ^ 465 co->co_argcount ^ co->co_nlocals ^ co->co_flags; 466 if (h == -1) h = -2; 467 return h; 468 } 469 470 /* XXX code objects need to participate in GC? */ 471 472 PyTypeObject PyCode_Type = { 473 PyVarObject_HEAD_INIT(&PyType_Type, 0) 474 "code", 475 sizeof(PyCodeObject), 476 0, 477 (destructor)code_dealloc, /* tp_dealloc */ 478 0, /* tp_print */ 479 0, /* tp_getattr */ 480 0, /* tp_setattr */ 481 (cmpfunc)code_compare, /* tp_compare */ 482 (reprfunc)code_repr, /* tp_repr */ 483 0, /* tp_as_number */ 484 0, /* tp_as_sequence */ 485 0, /* tp_as_mapping */ 486 (hashfunc)code_hash, /* tp_hash */ 487 0, /* tp_call */ 488 0, /* tp_str */ 489 PyObject_GenericGetAttr, /* tp_getattro */ 490 0, /* tp_setattro */ 491 0, /* tp_as_buffer */ 492 Py_TPFLAGS_DEFAULT, /* tp_flags */ 493 code_doc, /* tp_doc */ 494 0, /* tp_traverse */ 495 0, /* tp_clear */ 496 code_richcompare, /* tp_richcompare */ 497 offsetof(PyCodeObject, co_weakreflist), /* tp_weaklistoffset */ 498 0, /* tp_iter */ 499 0, /* tp_iternext */ 500 0, /* tp_methods */ 501 code_memberlist, /* tp_members */ 502 0, /* tp_getset */ 503 0, /* tp_base */ 504 0, /* tp_dict */ 505 0, /* tp_descr_get */ 506 0, /* tp_descr_set */ 507 0, /* tp_dictoffset */ 508 0, /* tp_init */ 509 0, /* tp_alloc */ 510 code_new, /* tp_new */ 511 }; 512 513 /* Use co_lnotab to compute the line number from a bytecode index, addrq. See 514 lnotab_notes.txt for the details of the lnotab representation. 515 */ 516 517 int 518 PyCode_Addr2Line(PyCodeObject *co, int addrq) 519 { 520 int size = PyString_Size(co->co_lnotab) / 2; 521 unsigned char *p = (unsigned char*)PyString_AsString(co->co_lnotab); 522 int line = co->co_firstlineno; 523 int addr = 0; 524 while (--size >= 0) { 525 addr += *p++; 526 if (addr > addrq) 527 break; 528 line += *p++; 529 } 530 return line; 531 } 532 533 /* Update *bounds to describe the first and one-past-the-last instructions in 534 the same line as lasti. Return the number of that line. */ 535 int 536 _PyCode_CheckLineNumber(PyCodeObject* co, int lasti, PyAddrPair *bounds) 537 { 538 int size, addr, line; 539 unsigned char* p; 540 541 p = (unsigned char*)PyString_AS_STRING(co->co_lnotab); 542 size = PyString_GET_SIZE(co->co_lnotab) / 2; 543 544 addr = 0; 545 line = co->co_firstlineno; 546 assert(line > 0); 547 548 /* possible optimization: if f->f_lasti == instr_ub 549 (likely to be a common case) then we already know 550 instr_lb -- if we stored the matching value of p 551 somwhere we could skip the first while loop. */ 552 553 /* See lnotab_notes.txt for the description of 554 co_lnotab. A point to remember: increments to p 555 come in (addr, line) pairs. */ 556 557 bounds->ap_lower = 0; 558 while (size > 0) { 559 if (addr + *p > lasti) 560 break; 561 addr += *p++; 562 if (*p) 563 bounds->ap_lower = addr; 564 line += *p++; 565 --size; 566 } 567 568 if (size > 0) { 569 while (--size >= 0) { 570 addr += *p++; 571 if (*p++) 572 break; 573 } 574 bounds->ap_upper = addr; 575 } 576 else { 577 bounds->ap_upper = INT_MAX; 578 } 579 580 return line; 581 } 582