1 #define PERL_NO_GET_CONTEXT 2 #include "EXTERN.h" 3 #include "perl.h" 4 #include "XSUB.h" 5 6 /* PL_maxo shouldn't differ from MAXO but leave room anyway (see BOOT:) */ 7 #define OP_MASK_BUF_SIZE (MAXO + 100) 8 9 /* XXX op_named_bits and opset_all are never freed */ 10 #define MY_CXT_KEY "Opcode::_guts" XS_VERSION 11 12 typedef struct { 13 HV * x_op_named_bits; /* cache shared for whole process */ 14 SV * x_opset_all; /* mask with all bits set */ 15 IV x_opset_len; /* length of opmasks in bytes */ 16 int x_opcode_debug; 17 } my_cxt_t; 18 19 START_MY_CXT 20 21 #define op_named_bits (MY_CXT.x_op_named_bits) 22 #define opset_all (MY_CXT.x_opset_all) 23 #define opset_len (MY_CXT.x_opset_len) 24 #define opcode_debug (MY_CXT.x_opcode_debug) 25 26 static SV *new_opset (pTHX_ SV *old_opset); 27 static int verify_opset (pTHX_ SV *opset, int fatal); 28 static void set_opset_bits (pTHX_ char *bitmap, SV *bitspec, int on, const char *opname); 29 static void put_op_bitspec (pTHX_ const char *optag, STRLEN len, SV *opset); 30 static SV *get_op_bitspec (pTHX_ const char *opname, STRLEN len, int fatal); 31 32 33 /* Initialise our private op_named_bits HV. 34 * It is first loaded with the name and number of each perl operator. 35 * Then the builtin tags :none and :all are added. 36 * Opcode.pm loads the standard optags from __DATA__ 37 * XXX leak-alert: data allocated here is never freed, call this 38 * at most once 39 */ 40 41 static void 42 op_names_init(pTHX) 43 { 44 int i; 45 STRLEN len; 46 char **op_names; 47 char *bitmap; 48 dMY_CXT; 49 50 op_named_bits = newHV(); 51 op_names = get_op_names(); 52 for(i=0; i < PL_maxo; ++i) { 53 SV * const sv = newSViv(i); 54 SvREADONLY_on(sv); 55 (void) hv_store(op_named_bits, op_names[i], strlen(op_names[i]), sv, 0); 56 } 57 58 put_op_bitspec(aTHX_ STR_WITH_LEN(":none"), sv_2mortal(new_opset(aTHX_ Nullsv))); 59 60 opset_all = new_opset(aTHX_ Nullsv); 61 bitmap = SvPV(opset_all, len); 62 memset(bitmap, 0xFF, len-1); /* deal with last byte specially, see below */ 63 /* Take care to set the right number of bits in the last byte */ 64 bitmap[len-1] = (PL_maxo & 0x07) ? ~(0xFF << (PL_maxo & 0x07)) : 0xFF; 65 put_op_bitspec(aTHX_ STR_WITH_LEN(":all"), opset_all); /* don't mortalise */ 66 } 67 68 69 /* Store a new tag definition. Always a mask. 70 * The tag must not already be defined. 71 * SV *mask is copied not referenced. 72 */ 73 74 static void 75 put_op_bitspec(pTHX_ const char *optag, STRLEN len, SV *mask) 76 { 77 SV **svp; 78 dMY_CXT; 79 80 verify_opset(aTHX_ mask,1); 81 svp = hv_fetch(op_named_bits, optag, len, 1); 82 if (SvOK(*svp)) 83 croak("Opcode tag \"%s\" already defined", optag); 84 sv_setsv(*svp, mask); 85 SvREADONLY_on(*svp); 86 } 87 88 89 90 /* Fetch a 'bits' entry for an opname or optag (IV/PV). 91 * Note that we return the actual entry for speed. 92 * Always sv_mortalcopy() if returning it to user code. 93 */ 94 95 static SV * 96 get_op_bitspec(pTHX_ const char *opname, STRLEN len, int fatal) 97 { 98 SV **svp; 99 dMY_CXT; 100 101 svp = hv_fetch(op_named_bits, opname, len, 0); 102 if (!svp || !SvOK(*svp)) { 103 if (!fatal) 104 return Nullsv; 105 if (*opname == ':') 106 croak("Unknown operator tag \"%s\"", opname); 107 if (*opname == '!') /* XXX here later, or elsewhere? */ 108 croak("Can't negate operators here (\"%s\")", opname); 109 if (isALPHA(*opname)) 110 croak("Unknown operator name \"%s\"", opname); 111 croak("Unknown operator prefix \"%s\"", opname); 112 } 113 return *svp; 114 } 115 116 117 118 static SV * 119 new_opset(pTHX_ SV *old_opset) 120 { 121 SV *opset; 122 dMY_CXT; 123 124 if (old_opset) { 125 verify_opset(aTHX_ old_opset,1); 126 opset = newSVsv(old_opset); 127 } 128 else { 129 opset = newSV(opset_len); 130 Zero(SvPVX_const(opset), opset_len + 1, char); 131 SvCUR_set(opset, opset_len); 132 (void)SvPOK_only(opset); 133 } 134 /* not mortalised here */ 135 return opset; 136 } 137 138 139 static int 140 verify_opset(pTHX_ SV *opset, int fatal) 141 { 142 const char *err = NULL; 143 dMY_CXT; 144 145 if (!SvOK(opset)) err = "undefined"; 146 else if (!SvPOK(opset)) err = "wrong type"; 147 else if (SvCUR(opset) != (STRLEN)opset_len) err = "wrong size"; 148 if (err && fatal) { 149 croak("Invalid opset: %s", err); 150 } 151 return !err; 152 } 153 154 155 static void 156 set_opset_bits(pTHX_ char *bitmap, SV *bitspec, int on, const char *opname) 157 { 158 dMY_CXT; 159 160 if (SvIOK(bitspec)) { 161 const int myopcode = SvIV(bitspec); 162 const int offset = myopcode >> 3; 163 const int bit = myopcode & 0x07; 164 if (myopcode >= PL_maxo || myopcode < 0) 165 croak("panic: opcode \"%s\" value %d is invalid", opname, myopcode); 166 if (opcode_debug >= 2) 167 warn("set_opset_bits bit %2d (off=%d, bit=%d) %s %s\n", 168 myopcode, offset, bit, opname, (on)?"on":"off"); 169 if (on) 170 bitmap[offset] |= 1 << bit; 171 else 172 bitmap[offset] &= ~(1 << bit); 173 } 174 else if (SvPOK(bitspec) && SvCUR(bitspec) == (STRLEN)opset_len) { 175 176 STRLEN len; 177 const char * const specbits = SvPV(bitspec, len); 178 if (opcode_debug >= 2) 179 warn("set_opset_bits opset %s %s\n", opname, (on)?"on":"off"); 180 if (on) 181 while(len-- > 0) bitmap[len] |= specbits[len]; 182 else 183 while(len-- > 0) bitmap[len] &= ~specbits[len]; 184 } 185 else 186 croak("panic: invalid bitspec for \"%s\" (type %u)", 187 opname, (unsigned)SvTYPE(bitspec)); 188 } 189 190 191 static void 192 opmask_add(pTHX_ SV *opset) /* THE ONLY FUNCTION TO EDIT PL_op_mask ITSELF */ 193 { 194 int i,j; 195 char *bitmask; 196 STRLEN len; 197 int myopcode = 0; 198 dMY_CXT; 199 200 verify_opset(aTHX_ opset,1); /* croaks on bad opset */ 201 202 if (!PL_op_mask) /* caller must ensure PL_op_mask exists */ 203 croak("Can't add to uninitialised PL_op_mask"); 204 205 /* OPCODES ALREADY MASKED ARE NEVER UNMASKED. See opmask_addlocal() */ 206 207 bitmask = SvPV(opset, len); 208 for (i=0; i < opset_len; i++) { 209 const U16 bits = bitmask[i]; 210 if (!bits) { /* optimise for sparse masks */ 211 myopcode += 8; 212 continue; 213 } 214 for (j=0; j < 8 && myopcode < PL_maxo; ) 215 PL_op_mask[myopcode++] |= bits & (1 << j++); 216 } 217 } 218 219 static void 220 opmask_addlocal(pTHX_ SV *opset, char *op_mask_buf) /* Localise PL_op_mask then opmask_add() */ 221 { 222 char *orig_op_mask = PL_op_mask; 223 dMY_CXT; 224 225 SAVEVPTR(PL_op_mask); 226 /* XXX casting to an ordinary function ptr from a member function ptr 227 * is disallowed by Borland 228 */ 229 if (opcode_debug >= 2) 230 SAVEDESTRUCTOR((void(*)(void*))Perl_warn,"PL_op_mask restored"); 231 PL_op_mask = &op_mask_buf[0]; 232 if (orig_op_mask) 233 Copy(orig_op_mask, PL_op_mask, PL_maxo, char); 234 else 235 Zero(PL_op_mask, PL_maxo, char); 236 opmask_add(aTHX_ opset); 237 } 238 239 240 241 MODULE = Opcode PACKAGE = Opcode 242 243 PROTOTYPES: ENABLE 244 245 BOOT: 246 { 247 MY_CXT_INIT; 248 assert(PL_maxo < OP_MASK_BUF_SIZE); 249 opset_len = (PL_maxo + 7) / 8; 250 if (opcode_debug >= 1) 251 warn("opset_len %ld\n", (long)opset_len); 252 op_names_init(aTHX); 253 } 254 255 void 256 _safe_pkg_prep(Package) 257 SV *Package 258 PPCODE: 259 HV *hv; 260 ENTER; 261 262 hv = gv_stashsv(Package, GV_ADDWARN); /* should exist already */ 263 264 if (strNE(HvNAME_get(hv),"main")) { 265 /* make it think it's in main:: */ 266 hv_name_set(hv, "main", 4, 0); 267 (void) hv_store(hv,"_",1,(SV *)PL_defgv,0); /* connect _ to global */ 268 SvREFCNT_inc((SV *)PL_defgv); /* want to keep _ around! */ 269 } 270 LEAVE; 271 272 273 274 275 276 void 277 _safe_call_sv(Package, mask, codesv) 278 SV * Package 279 SV * mask 280 SV * codesv 281 PPCODE: 282 char op_mask_buf[OP_MASK_BUF_SIZE]; 283 GV *gv; 284 HV *dummy_hv; 285 286 ENTER; 287 288 opmask_addlocal(aTHX_ mask, op_mask_buf); 289 290 save_aptr(&PL_endav); 291 PL_endav = (AV*)sv_2mortal((SV*)newAV()); /* ignore END blocks for now */ 292 293 save_hptr(&PL_defstash); /* save current default stash */ 294 /* the assignment to global defstash changes our sense of 'main' */ 295 PL_defstash = gv_stashsv(Package, GV_ADDWARN); /* should exist already */ 296 297 SAVEGENERICSV(PL_curstash); 298 PL_curstash = (HV *)SvREFCNT_inc_simple(PL_defstash); 299 300 /* defstash must itself contain a main:: so we'll add that now */ 301 /* take care with the ref counts (was cause of long standing bug) */ 302 /* XXX I'm still not sure if this is right, GV_ADDWARN should warn! */ 303 gv = gv_fetchpvs("main::", GV_ADDWARN, SVt_PVHV); 304 sv_free((SV*)GvHV(gv)); 305 GvHV(gv) = (HV*)SvREFCNT_inc(PL_defstash); 306 307 /* %INC must be clean for use/require in compartment */ 308 dummy_hv = save_hash(PL_incgv); 309 GvHV(PL_incgv) = (HV*)SvREFCNT_inc(GvHV(gv_HVadd(gv_fetchpvs("INC",GV_ADD,SVt_PVHV)))); 310 311 /* Invalidate ISA and method caches */ 312 ++PL_sub_generation; 313 hv_clear(PL_stashcache); 314 315 PUSHMARK(SP); 316 perl_call_sv(codesv, GIMME|G_EVAL|G_KEEPERR); /* use callers context */ 317 sv_free( (SV *) dummy_hv); /* get rid of what save_hash gave us*/ 318 SPAGAIN; /* for the PUTBACK added by xsubpp */ 319 LEAVE; 320 321 322 int 323 verify_opset(opset, fatal = 0) 324 SV *opset 325 int fatal 326 CODE: 327 RETVAL = verify_opset(aTHX_ opset,fatal); 328 OUTPUT: 329 RETVAL 330 331 void 332 invert_opset(opset) 333 SV *opset 334 CODE: 335 { 336 char *bitmap; 337 dMY_CXT; 338 STRLEN len = opset_len; 339 340 opset = sv_2mortal(new_opset(aTHX_ opset)); /* verify and clone opset */ 341 bitmap = SvPVX(opset); 342 while(len-- > 0) 343 bitmap[len] = ~bitmap[len]; 344 /* take care of extra bits beyond PL_maxo in last byte */ 345 if (PL_maxo & 07) 346 bitmap[opset_len-1] &= ~(0xFF << (PL_maxo & 0x07)); 347 } 348 ST(0) = opset; 349 350 351 void 352 opset_to_ops(opset, desc = 0) 353 SV *opset 354 int desc 355 PPCODE: 356 { 357 STRLEN len; 358 int i, j, myopcode; 359 const char * const bitmap = SvPV(opset, len); 360 char **names = (desc) ? get_op_descs() : get_op_names(); 361 dMY_CXT; 362 363 verify_opset(aTHX_ opset,1); 364 for (myopcode=0, i=0; i < opset_len; i++) { 365 const U16 bits = bitmap[i]; 366 for (j=0; j < 8 && myopcode < PL_maxo; j++, myopcode++) { 367 if ( bits & (1 << j) ) 368 XPUSHs(newSVpvn_flags(names[myopcode], strlen(names[myopcode]), 369 SVs_TEMP)); 370 } 371 } 372 } 373 374 375 void 376 opset(...) 377 CODE: 378 int i; 379 SV *bitspec; 380 STRLEN len, on; 381 382 SV * const opset = sv_2mortal(new_opset(aTHX_ Nullsv)); 383 char * const bitmap = SvPVX(opset); 384 for (i = 0; i < items; i++) { 385 const char *opname; 386 on = 1; 387 if (verify_opset(aTHX_ ST(i),0)) { 388 opname = "(opset)"; 389 bitspec = ST(i); 390 } 391 else { 392 opname = SvPV(ST(i), len); 393 if (*opname == '!') { on=0; ++opname;--len; } 394 bitspec = get_op_bitspec(aTHX_ opname, len, 1); 395 } 396 set_opset_bits(aTHX_ bitmap, bitspec, on, opname); 397 } 398 ST(0) = opset; 399 400 401 #define PERMITING (ix == 0 || ix == 1) 402 #define ONLY_THESE (ix == 0 || ix == 2) 403 404 void 405 permit_only(safe, ...) 406 SV *safe 407 ALIAS: 408 permit = 1 409 deny_only = 2 410 deny = 3 411 CODE: 412 int i; 413 SV *bitspec, *mask; 414 char *bitmap; 415 STRLEN len; 416 dMY_CXT; 417 418 if (!SvROK(safe) || !SvOBJECT(SvRV(safe)) || SvTYPE(SvRV(safe))!=SVt_PVHV) 419 croak("Not a Safe object"); 420 mask = *hv_fetch((HV*)SvRV(safe), "Mask",4, 1); 421 if (ONLY_THESE) /* *_only = new mask, else edit current */ 422 sv_setsv(mask, sv_2mortal(new_opset(aTHX_ PERMITING ? opset_all : Nullsv))); 423 else 424 verify_opset(aTHX_ mask,1); /* croaks */ 425 bitmap = SvPVX(mask); 426 for (i = 1; i < items; i++) { 427 const char *opname; 428 int on = PERMITING ? 0 : 1; /* deny = mask bit on */ 429 if (verify_opset(aTHX_ ST(i),0)) { /* it's a valid mask */ 430 opname = "(opset)"; 431 bitspec = ST(i); 432 } 433 else { /* it's an opname/optag */ 434 opname = SvPV(ST(i), len); 435 /* invert if op has ! prefix (only one allowed) */ 436 if (*opname == '!') { on = !on; ++opname; --len; } 437 bitspec = get_op_bitspec(aTHX_ opname, len, 1); /* croaks */ 438 } 439 set_opset_bits(aTHX_ bitmap, bitspec, on, opname); 440 } 441 ST(0) = &PL_sv_yes; 442 443 444 445 void 446 opdesc(...) 447 PPCODE: 448 int i; 449 STRLEN len; 450 SV **args; 451 char **op_desc = get_op_descs(); 452 dMY_CXT; 453 454 /* copy args to a scratch area since we may push output values onto */ 455 /* the stack faster than we read values off it if masks are used. */ 456 args = (SV**)SvPVX(newSVpvn_flags((char*)&ST(0), items*sizeof(SV*), SVs_TEMP)); 457 for (i = 0; i < items; i++) { 458 const char * const opname = SvPV(args[i], len); 459 SV *bitspec = get_op_bitspec(aTHX_ opname, len, 1); 460 if (SvIOK(bitspec)) { 461 const int myopcode = SvIV(bitspec); 462 if (myopcode < 0 || myopcode >= PL_maxo) 463 croak("panic: opcode %d (%s) out of range",myopcode,opname); 464 XPUSHs(newSVpvn_flags(op_desc[myopcode], strlen(op_desc[myopcode]), 465 SVs_TEMP)); 466 } 467 else if (SvPOK(bitspec) && SvCUR(bitspec) == (STRLEN)opset_len) { 468 int b, j; 469 const char * const bitmap = SvPV_nolen_const(bitspec); 470 int myopcode = 0; 471 for (b=0; b < opset_len; b++) { 472 const U16 bits = bitmap[b]; 473 for (j=0; j < 8 && myopcode < PL_maxo; j++, myopcode++) 474 if (bits & (1 << j)) 475 XPUSHs(newSVpvn_flags(op_desc[myopcode], 476 strlen(op_desc[myopcode]), 477 SVs_TEMP)); 478 } 479 } 480 else 481 croak("panic: invalid bitspec for \"%s\" (type %u)", 482 opname, (unsigned)SvTYPE(bitspec)); 483 } 484 485 486 void 487 define_optag(optagsv, mask) 488 SV *optagsv 489 SV *mask 490 CODE: 491 STRLEN len; 492 const char *optag = SvPV(optagsv, len); 493 494 put_op_bitspec(aTHX_ optag, len, mask); /* croaks */ 495 ST(0) = &PL_sv_yes; 496 497 498 void 499 empty_opset() 500 CODE: 501 ST(0) = sv_2mortal(new_opset(aTHX_ Nullsv)); 502 503 void 504 full_opset() 505 CODE: 506 dMY_CXT; 507 ST(0) = sv_2mortal(new_opset(aTHX_ opset_all)); 508 509 void 510 opmask_add(opset) 511 SV *opset 512 PREINIT: 513 if (!PL_op_mask) 514 Newxz(PL_op_mask, PL_maxo, char); 515 CODE: 516 opmask_add(aTHX_ opset); 517 518 void 519 opcodes() 520 PPCODE: 521 if (GIMME == G_ARRAY) { 522 croak("opcodes in list context not yet implemented"); /* XXX */ 523 } 524 else { 525 XPUSHs(sv_2mortal(newSViv(PL_maxo))); 526 } 527 528 void 529 opmask() 530 CODE: 531 ST(0) = sv_2mortal(new_opset(aTHX_ Nullsv)); 532 if (PL_op_mask) { 533 char * const bitmap = SvPVX(ST(0)); 534 int myopcode; 535 for(myopcode=0; myopcode < PL_maxo; ++myopcode) { 536 if (PL_op_mask[myopcode]) 537 bitmap[myopcode >> 3] |= 1 << (myopcode & 0x07); 538 } 539 } 540 541