indirect.xs

   1 /* This file is part of the indirect Perl module.
   2  * See http://search.cpan.org/dist/indirect/ */
   3
   4 #define PERL_NO_GET_CONTEXT
   5 #include "EXTERN.h"
   6 #include "perl.h"
   7 #include "XSUB.h"
   8
   9 #define __PACKAGE__     "indirect"
  10 #define __PACKAGE_LEN__ (sizeof(__PACKAGE__)-1)
  11
  12 /* --- Compatibility wrappers ---------------------------------------------- */
  13
  14 #ifndef NOOP
  15 # define NOOP
  16 #endif
  17
  18 #ifndef dNOOP
  19 # define dNOOP
  20 #endif
  21
  22 #ifndef Newx
  23 # define Newx(v, n, c) New(0, v, n, c)
  24 #endif
  25
  26 #ifndef SvPV_const
  27 # define SvPV_const SvPV
  28 #endif
  29
  30 #ifndef SvPV_nolen_const
  31 # define SvPV_nolen_const SvPV_nolen
  32 #endif
  33
  34 #ifndef SvPVX_const
  35 # define SvPVX_const SvPVX
  36 #endif
  37
  38 #ifndef SvREFCNT_inc_simple_NN
  39 # define SvREFCNT_inc_simple_NN SvREFCNT_inc
  40 #endif
  41
  42 #ifndef sv_catpvn_nomg
  43 # define sv_catpvn_nomg sv_catpvn
  44 #endif
  45
  46 #ifndef mPUSHp
  47 # define mPUSHp(P, L) PUSHs(sv_2mortal(newSVpvn((P), (L))))
  48 #endif
  49
  50 #ifndef mPUSHu
  51 # define mPUSHu(U) PUSHs(sv_2mortal(newSVuv(U)))
  52 #endif
  53
  54 #ifndef HvNAME_get
  55 # define HvNAME_get(H) HvNAME(H)
  56 #endif
  57
  58 #ifndef HvNAMELEN_get
  59 # define HvNAMELEN_get(H) strlen(HvNAME_get(H))
  60 #endif
  61
  62 #define I_HAS_PERL(R, V, S) (PERL_REVISION > (R) || (PERL_REVISION == (R) && (PERL_VERSION > (V) || (PERL_VERSION == (V) && (PERL_SUBVERSION >= (S))))))
  63
  64 #if I_HAS_PERL(5, 10, 0) || defined(PL_parser)
  65 # ifndef PL_linestr
  66 #  define PL_linestr PL_parser->linestr
  67 # endif
  68 # ifndef PL_bufptr
  69 #  define PL_bufptr PL_parser->bufptr
  70 # endif
  71 # ifndef PL_oldbufptr
  72 #  define PL_oldbufptr PL_parser->oldbufptr
  73 # endif
  74 #else
  75 # ifndef PL_linestr
  76 #  define PL_linestr PL_Ilinestr
  77 # endif
  78 # ifndef PL_bufptr
  79 #  define PL_bufptr PL_Ibufptr
  80 # endif
  81 # ifndef PL_oldbufptr
  82 #  define PL_oldbufptr PL_Ioldbufptr
  83 # endif
  84 #endif
  85
  86 #ifndef I_WORKAROUND_REQUIRE_PROPAGATION
  87 # define I_WORKAROUND_REQUIRE_PROPAGATION !I_HAS_PERL(5, 12, 0)
  88 #endif
  89
  90 /* ... Thread safety and multiplicity ...................................... */
  91
  92 /* Safe unless stated otherwise in Makefile.PL */
  93 #ifndef I_FORKSAFE
  94 # define I_FORKSAFE 1
  95 #endif
  96
  97 #ifndef I_MULTIPLICITY
  98 # if defined(MULTIPLICITY) || defined(PERL_IMPLICIT_CONTEXT)
  99 #  define I_MULTIPLICITY 1
 100 # else
 101 #  define I_MULTIPLICITY 0
 102 # endif
 103 #endif
 104 #if I_MULTIPLICITY && !defined(tTHX)
 105 # define tTHX PerlInterpreter*
 106 #endif
 107
 108 #if I_MULTIPLICITY && defined(USE_ITHREADS) && defined(dMY_CXT) && defined(MY_CXT) && defined(START_MY_CXT) && defined(MY_CXT_INIT) && (defined(MY_CXT_CLONE) || defined(dMY_CXT_SV))
 109 # define I_THREADSAFE 1
 110 # ifndef MY_CXT_CLONE
 111 #  define MY_CXT_CLONE \
 112     dMY_CXT_SV;                                                      \
 113     my_cxt_t *my_cxtp = (my_cxt_t*)SvPVX(newSV(sizeof(my_cxt_t)-1)); \
 114     Copy(INT2PTR(my_cxt_t*, SvUV(my_cxt_sv)), my_cxtp, 1, my_cxt_t); \
 115     sv_setuv(my_cxt_sv, PTR2UV(my_cxtp))
 116 # endif
 117 #else
 118 # define I_THREADSAFE 0
 119 # undef  dMY_CXT
 120 # define dMY_CXT      dNOOP
 121 # undef  MY_CXT
 122 # define MY_CXT       indirect_globaldata
 123 # undef  START_MY_CXT
 124 # define START_MY_CXT STATIC my_cxt_t MY_CXT;
 125 # undef  MY_CXT_INIT
 126 # define MY_CXT_INIT  NOOP
 127 # undef  MY_CXT_CLONE
 128 # define MY_CXT_CLONE NOOP
 129 #endif
 130
 131 /* --- Helpers ------------------------------------------------------------- */
 132
 133 /* ... Thread-safe hints ................................................... */
 134
 135 #if I_WORKAROUND_REQUIRE_PROPAGATION
 136
 137 typedef struct {
 138  SV *code;
 139  IV  require_tag;
 140 } indirect_hint_t;
 141
 142 #define I_HINT_STRUCT 1
 143
 144 #define I_HINT_CODE(H) ((H)->code)
 145
 146 #define I_HINT_FREE(H) {   \
 147  indirect_hint_t *h = (H); \
 148  SvREFCNT_dec(h->code);    \
 149  PerlMemShared_free(h);    \
 150 }
 151
 152 #else  /*  I_WORKAROUND_REQUIRE_PROPAGATION */
 153
 154 typedef SV indirect_hint_t;
 155
 156 #define I_HINT_STRUCT 0
 157
 158 #define I_HINT_CODE(H) (H)
 159
 160 #define I_HINT_FREE(H) SvREFCNT_dec(H);
 161
 162 #endif /* !I_WORKAROUND_REQUIRE_PROPAGATION */
 163
 164 #if I_THREADSAFE
 165
 166 #define PTABLE_NAME        ptable_hints
 167 #define PTABLE_VAL_FREE(V) I_HINT_FREE(V)
 168
 169 #define pPTBL  pTHX
 170 #define pPTBL_ pTHX_
 171 #define aPTBL  aTHX
 172 #define aPTBL_ aTHX_
 173
 174 #include "ptable.h"
 175
 176 #define ptable_hints_store(T, K, V) ptable_hints_store(aTHX_ (T), (K), (V))
 177 #define ptable_hints_free(T)        ptable_hints_free(aTHX_ (T))
 178
 179 #endif /* I_THREADSAFE */
 180
 181 /* Define the op->str ptable here because we need to be able to clean it during
 182  * thread cleanup. */
 183
 184 typedef struct {
 185  STRLEN  pos;
 186  STRLEN  size;
 187  STRLEN  len;
 188  char   *buf;
 189  line_t  line;
 190 } indirect_op_info_t;
 191
 192 #define PTABLE_NAME        ptable
 193 #define PTABLE_VAL_FREE(V) if (V) { Safefree(((indirect_op_info_t *) (V))->buf); Safefree(V); }
 194
 195 #define pPTBL  pTHX
 196 #define pPTBL_ pTHX_
 197 #define aPTBL  aTHX
 198 #define aPTBL_ aTHX_
 199
 200 #include "ptable.h"
 201
 202 #define ptable_store(T, K, V) ptable_store(aTHX_ (T), (K), (V))
 203 #define ptable_clear(T)       ptable_clear(aTHX_ (T))
 204 #define ptable_free(T)        ptable_free(aTHX_ (T))
 205
 206 #define MY_CXT_KEY __PACKAGE__ "::_guts" XS_VERSION
 207
 208 typedef struct {
 209 #if I_THREADSAFE
 210  ptable *tbl; /* It really is a ptable_hints */
 211  tTHX    owner;
 212 #endif
 213  ptable *map;
 214 } my_cxt_t;
 215
 216 START_MY_CXT
 217
 218 #if I_THREADSAFE
 219
 220 STATIC SV *indirect_clone(pTHX_ SV *sv, tTHX owner) {
 221 #define indirect_clone(S, O) indirect_clone(aTHX_ (S), (O))
 222  CLONE_PARAMS  param;
 223  AV           *stashes = NULL;
 224  SV           *dupsv;
 225
 226  if (SvTYPE(sv) == SVt_PVHV && HvNAME_get(sv))
 227   stashes = newAV();
 228
 229  param.stashes    = stashes;
 230  param.flags      = 0;
 231  param.proto_perl = owner;
 232
 233  dupsv = sv_dup(sv, &param);
 234
 235  if (stashes) {
 236   av_undef(stashes);
 237   SvREFCNT_dec(stashes);
 238  }
 239
 240  return SvREFCNT_inc(dupsv);
 241 }
 242
 243 STATIC void indirect_ptable_clone(pTHX_ ptable_ent *ent, void *ud_) {
 244  my_cxt_t        *ud = ud_;
 245  indirect_hint_t *h1 = ent->val;
 246  indirect_hint_t *h2;
 247
 248  if (ud->owner == aTHX)
 249   return;
 250
 251 #if I_HINT_STRUCT
 252
 253  h2       = PerlMemShared_malloc(sizeof *h2);
 254  h2->code = indirect_clone(h1->code, ud->owner);
 255  SvREFCNT_inc(h2->code);
 256 #if I_WORKAROUND_REQUIRE_PROPAGATION
 257  h2->require_tag = PTR2IV(indirect_clone(INT2PTR(SV *, h1->require_tag),
 258                                          ud->owner));
 259 #endif
 260
 261 #else  /*  I_HINT_STRUCT */
 262
 263  h2 = indirect_clone(h1, ud->owner);
 264  SvREFCNT_inc(h2);
 265
 266 #endif /* !I_HINT_STRUCT */
 267
 268  ptable_hints_store(ud->tbl, ent->key, h2);
 269 }
 270
 271 #include "reap.h"
 272
 273 STATIC void indirect_thread_cleanup(pTHX_ void *ud) {
 274  dMY_CXT;
 275
 276  ptable_free(MY_CXT.map);
 277  ptable_hints_free(MY_CXT.tbl);
 278 }
 279
 280 #endif /* I_THREADSAFE */
 281
 282 #if I_WORKAROUND_REQUIRE_PROPAGATION
 283 STATIC IV indirect_require_tag(pTHX) {
 284 #define indirect_require_tag() indirect_require_tag(aTHX)
 285  const CV *cv, *outside;
 286
 287  cv = PL_compcv;
 288
 289  if (!cv) {
 290   /* If for some reason the pragma is operational at run-time, try to discover
 291    * the current cv in use. */
 292   const PERL_SI *si;
 293
 294   for (si = PL_curstackinfo; si; si = si->si_prev) {
 295    I32 cxix;
 296
 297    for (cxix = si->si_cxix; cxix >= 0; --cxix) {
 298     const PERL_CONTEXT *cx = si->si_cxstack + cxix;
 299
 300     switch (CxTYPE(cx)) {
 301      case CXt_SUB:
 302      case CXt_FORMAT:
 303       /* The propagation workaround is only needed up to 5.10.0 and at that
 304        * time format and sub contexts were still identical. And even later the
 305        * cv members offsets should have been kept the same. */
 306       cv = cx->blk_sub.cv;
 307       goto get_enclosing_cv;
 308      case CXt_EVAL:
 309       cv = cx->blk_eval.cv;
 310       goto get_enclosing_cv;
 311      default:
 312       break;
 313     }
 314    }
 315   }
 316
 317   cv = PL_main_cv;
 318  }
 319
 320 get_enclosing_cv:
 321  for (outside = CvOUTSIDE(cv); outside; outside = CvOUTSIDE(cv))
 322   cv = outside;
 323
 324  return PTR2IV(cv);
 325 }
 326 #endif /* I_WORKAROUND_REQUIRE_PROPAGATION */
 327
 328 STATIC SV *indirect_tag(pTHX_ SV *value) {
 329 #define indirect_tag(V) indirect_tag(aTHX_ (V))
 330  indirect_hint_t *h;
 331  SV *code = NULL;
 332  dMY_CXT;
 333
 334  if (SvROK(value)) {
 335   value = SvRV(value);
 336   if (SvTYPE(value) >= SVt_PVCV) {
 337    code = value;
 338    SvREFCNT_inc_simple_NN(code);
 339   }
 340  }
 341
 342 #if I_HINT_STRUCT
 343  h = PerlMemShared_malloc(sizeof *h);
 344  h->code        = code;
 345 # if I_WORKAROUND_REQUIRE_PROPAGATION
 346  h->require_tag = indirect_require_tag();
 347 # endif /* I_WORKAROUND_REQUIRE_PROPAGATION */
 348 #else  /*  I_HINT_STRUCT */
 349  h = code;
 350 #endif /* !I_HINT_STRUCT */
 351
 352 #if I_THREADSAFE
 353  /* We only need for the key to be an unique tag for looking up the value later.
 354   * Allocated memory provides convenient unique identifiers, so that's why we
 355   * use the hint as the key itself. */
 356  ptable_hints_store(MY_CXT.tbl, h, h);
 357 #endif /* I_THREADSAFE */
 358
 359  return newSViv(PTR2IV(h));
 360 }
 361
 362 STATIC SV *indirect_detag(pTHX_ const SV *hint) {
 363 #define indirect_detag(H) indirect_detag(aTHX_ (H))
 364  indirect_hint_t *h;
 365  dMY_CXT;
 366
 367  if (!(hint && SvIOK(hint)))
 368   return NULL;
 369
 370  h = INT2PTR(indirect_hint_t *, SvIVX(hint));
 371 #if I_THREADSAFE
 372  h = ptable_fetch(MY_CXT.tbl, h);
 373 #endif /* I_THREADSAFE */
 374
 375 #if I_WORKAROUND_REQUIRE_PROPAGATION
 376  if (indirect_require_tag() != h->require_tag)
 377   return NULL;
 378 #endif /* I_WORKAROUND_REQUIRE_PROPAGATION */
 379
 380  return I_HINT_CODE(h);
 381 }
 382
 383 STATIC U32 indirect_hash = 0;
 384
 385 STATIC SV *indirect_hint(pTHX) {
 386 #define indirect_hint() indirect_hint(aTHX)
 387  SV **val;
 388
 389  if (IN_PERL_RUNTIME)
 390   return NULL;
 391
 392  val = hv_fetch(GvHV(PL_hintgv), __PACKAGE__, __PACKAGE_LEN__, indirect_hash);
 393  if (!val)
 394   return NULL;
 395
 396  return indirect_detag(*val);
 397 }
 398
 399 /* ... op -> source position ............................................... */
 400
 401 STATIC void indirect_map_store(pTHX_ const OP *o, STRLEN pos, SV *sv, line_t line) {
 402 #define indirect_map_store(O, P, N, L) indirect_map_store(aTHX_ (O), (P), (N), (L))
 403  indirect_op_info_t *oi;
 404  const char *s;
 405  STRLEN len;
 406  dMY_CXT;
 407
 408  if (!(oi = ptable_fetch(MY_CXT.map, o))) {
 409   Newx(oi, 1, indirect_op_info_t);
 410   ptable_store(MY_CXT.map, o, oi);
 411   oi->buf  = NULL;
 412   oi->size = 0;
 413  }
 414
 415  if (sv) {
 416   s = SvPV_const(sv, len);
 417  } else {
 418   s   = "{";
 419   len = 1;
 420  }
 421
 422  if (len > oi->size) {
 423   Safefree(oi->buf);
 424   Newx(oi->buf, len, char);
 425   oi->size = len;
 426  }
 427  Copy(s, oi->buf, len, char);
 428
 429  oi->len  = len;
 430  oi->pos  = pos;
 431  oi->line = line;
 432 }
 433
 434 STATIC const indirect_op_info_t *indirect_map_fetch(pTHX_ const OP *o) {
 435 #define indirect_map_fetch(O) indirect_map_fetch(aTHX_ (O))
 436  dMY_CXT;
 437
 438  return ptable_fetch(MY_CXT.map, o);
 439 }
 440
 441 STATIC void indirect_map_delete(pTHX_ const OP *o) {
 442 #define indirect_map_delete(O) indirect_map_delete(aTHX_ (O))
 443  dMY_CXT;
 444
 445  ptable_store(MY_CXT.map, o, NULL);
 446 }
 447
 448 /* --- Check functions ----------------------------------------------------- */
 449
 450 STATIC int indirect_find(pTHX_ SV *sv, const char *s, STRLEN *pos) {
 451 #define indirect_find(N, S, P) indirect_find(aTHX_ (N), (S), (P))
 452  STRLEN len;
 453  const char *p = NULL, *r = SvPV_const(sv, len);
 454
 455  if (len >= 1 && *r == '$') {
 456   ++r;
 457   --len;
 458   s = strchr(s, '$');
 459   if (!s)
 460    return 0;
 461  }
 462
 463  p = strstr(s, r);
 464  while (p) {
 465   p += len;
 466   if (!isALNUM(*p))
 467    break;
 468   p = strstr(p + 1, r);
 469  }
 470  if (!p)
 471   return 0;
 472
 473  *pos = p - SvPVX_const(PL_linestr);
 474
 475  return 1;
 476 }
 477
 478 /* ... ck_const ............................................................ */
 479
 480 STATIC OP *(*indirect_old_ck_const)(pTHX_ OP *) = 0;
 481
 482 STATIC OP *indirect_ck_const(pTHX_ OP *o) {
 483  o = CALL_FPTR(indirect_old_ck_const)(aTHX_ o);
 484
 485  if (indirect_hint()) {
 486   SV *sv = cSVOPo_sv;
 487
 488   if (SvPOK(sv) && (SvTYPE(sv) >= SVt_PV)) {
 489    STRLEN pos;
 490
 491    if (indirect_find(sv, PL_oldbufptr, &pos)) {
 492     indirect_map_store(o, pos, sv, CopLINE(&PL_compiling));
 493     return o;
 494    }
 495   }
 496  }
 497
 498  indirect_map_delete(o);
 499  return o;
 500 }
 501
 502 /* ... ck_rv2sv ............................................................ */
 503
 504 STATIC OP *(*indirect_old_ck_rv2sv)(pTHX_ OP *) = 0;
 505
 506 STATIC OP *indirect_ck_rv2sv(pTHX_ OP *o) {
 507  if (indirect_hint()) {
 508   OP *op = cUNOPo->op_first;
 509   SV *sv;
 510   const char *name = NULL;
 511   STRLEN pos, len;
 512   OPCODE type = (OPCODE) op->op_type;
 513
 514   switch (type) {
 515    case OP_GV:
 516    case OP_GVSV: {
 517     GV *gv = cGVOPx_gv(op);
 518     name = GvNAME(gv);
 519     len  = GvNAMELEN(gv);
 520     break;
 521    }
 522    default:
 523     if ((PL_opargs[type] & OA_CLASS_MASK) == OA_SVOP) {
 524      SV *nsv = cSVOPx_sv(op);
 525      if (SvPOK(nsv) && (SvTYPE(nsv) >= SVt_PV))
 526       name = SvPV_const(nsv, len);
 527     }
 528   }
 529   if (!name)
 530    goto done;
 531
 532   sv = sv_2mortal(newSVpvn("$", 1));
 533   sv_catpvn_nomg(sv, name, len);
 534   if (!indirect_find(sv, PL_oldbufptr, &pos)) {
 535    /* If it failed, retry without the current stash */
 536    const char *stash = HvNAME_get(PL_curstash);
 537    STRLEN stashlen = HvNAMELEN_get(PL_curstash);
 538
 539    if ((len < stashlen + 2) || strnNE(name, stash, stashlen)
 540        || name[stashlen] != ':' || name[stashlen+1] != ':') {
 541     /* Failed again ? Try to remove main */
 542     stash = "main";
 543     stashlen = 4;
 544     if ((len < stashlen + 2) || strnNE(name, stash, stashlen)
 545         || name[stashlen] != ':' || name[stashlen+1] != ':')
 546      goto done;
 547    }
 548
 549    sv_setpvn(sv, "$", 1);
 550    stashlen += 2;
 551    sv_catpvn_nomg(sv, name + stashlen, len - stashlen);
 552    if (!indirect_find(sv, PL_oldbufptr, &pos))
 553     goto done;
 554   }
 555
 556   o = CALL_FPTR(indirect_old_ck_rv2sv)(aTHX_ o);
 557
 558   indirect_map_store(o, pos, sv, CopLINE(&PL_compiling));
 559   return o;
 560  }
 561
 562 done:
 563  o = CALL_FPTR(indirect_old_ck_rv2sv)(aTHX_ o);
 564
 565  indirect_map_delete(o);
 566  return o;
 567 }
 568
 569 /* ... ck_padany ........................................................... */
 570
 571 STATIC OP *(*indirect_old_ck_padany)(pTHX_ OP *) = 0;
 572
 573 STATIC OP *indirect_ck_padany(pTHX_ OP *o) {
 574  o = CALL_FPTR(indirect_old_ck_padany)(aTHX_ o);
 575
 576  if (indirect_hint()) {
 577   SV *sv;
 578   const char *s = PL_oldbufptr, *t = PL_bufptr - 1;
 579
 580   while (s < t && isSPACE(*s)) ++s;
 581   if (*s == '$' && ++s <= t) {
 582    while (s < t && isSPACE(*s)) ++s;
 583    while (s < t && isSPACE(*t)) --t;
 584    sv = sv_2mortal(newSVpvn("$", 1));
 585    sv_catpvn_nomg(sv, s, t - s + 1);
 586    indirect_map_store(o, s - SvPVX_const(PL_linestr),
 587                          sv, CopLINE(&PL_compiling));
 588    return o;
 589   }
 590  }
 591
 592  indirect_map_delete(o);
 593  return o;
 594 }
 595
 596 /* ... ck_scope ............................................................ */
 597
 598 STATIC OP *(*indirect_old_ck_scope)  (pTHX_ OP *) = 0;
 599 STATIC OP *(*indirect_old_ck_lineseq)(pTHX_ OP *) = 0;
 600
 601 STATIC OP *indirect_ck_scope(pTHX_ OP *o) {
 602  OP *(*old_ck)(pTHX_ OP *) = 0;
 603
 604  switch (o->op_type) {
 605   case OP_SCOPE:   old_ck = indirect_old_ck_scope;   break;
 606   case OP_LINESEQ: old_ck = indirect_old_ck_lineseq; break;
 607  }
 608  o = CALL_FPTR(old_ck)(aTHX_ o);
 609
 610  if (indirect_hint()) {
 611   indirect_map_store(o, PL_oldbufptr - SvPVX_const(PL_linestr),
 612                         NULL, CopLINE(&PL_compiling));
 613   return o;
 614  }
 615
 616  indirect_map_delete(o);
 617  return o;
 618 }
 619
 620 /* We don't need to clean the map entries for leave ops because they can only
 621  * be created by mutating from a lineseq. */
 622
 623 /* ... ck_method ........................................................... */
 624
 625 STATIC OP *(*indirect_old_ck_method)(pTHX_ OP *) = 0;
 626
 627 STATIC OP *indirect_ck_method(pTHX_ OP *o) {
 628  if (indirect_hint()) {
 629   OP *op = cUNOPo->op_first;
 630
 631   /* Indirect method call is only possible when the method is a bareword, so
 632    * don't trip up on $obj->$meth. */
 633   if (op && op->op_type == OP_CONST) {
 634    const indirect_op_info_t *oi = indirect_map_fetch(op);
 635    STRLEN pos;
 636    line_t line;
 637    SV *sv;
 638
 639    if (!oi)
 640     goto done;
 641
 642    sv   = sv_2mortal(newSVpvn(oi->buf, oi->len));
 643    pos  = oi->pos;
 644    /* Keep the old line so that we really point to the first line of the
 645     * expression. */
 646    line = oi->line;
 647
 648    o = CALL_FPTR(indirect_old_ck_method)(aTHX_ o);
 649    /* o may now be a method_named */
 650
 651    indirect_map_store(o, pos, sv, line);
 652    return o;
 653   }
 654  }
 655
 656 done:
 657  o = CALL_FPTR(indirect_old_ck_method)(aTHX_ o);
 658
 659  indirect_map_delete(o);
 660  return o;
 661 }
 662
 663 /* ... ck_method_named ..................................................... */
 664
 665 /* "use foo/no foo" compiles its call to import/unimport directly to a
 666  * method_named op. */
 667
 668 STATIC OP *(*indirect_old_ck_method_named)(pTHX_ OP *) = 0;
 669
 670 STATIC OP *indirect_ck_method_named(pTHX_ OP *o) {
 671  if (indirect_hint()) {
 672   STRLEN pos;
 673   line_t line;
 674   SV *sv;
 675
 676   sv = cSVOPo_sv;
 677   if (!SvPOK(sv) || (SvTYPE(sv) < SVt_PV))
 678    goto done;
 679   sv = sv_mortalcopy(sv);
 680
 681   if (!indirect_find(sv, PL_oldbufptr, &pos))
 682    goto done;
 683   line = CopLINE(&PL_compiling);
 684
 685   o = CALL_FPTR(indirect_old_ck_method_named)(aTHX_ o);
 686
 687   indirect_map_store(o, pos, sv, line);
 688   return o;
 689  }
 690
 691 done:
 692  o = CALL_FPTR(indirect_old_ck_method_named)(aTHX_ o);
 693
 694  indirect_map_delete(o);
 695  return o;
 696 }
 697
 698 /* ... ck_entersub ......................................................... */
 699
 700 STATIC int indirect_is_indirect(const indirect_op_info_t *moi, const indirect_op_info_t *ooi) {
 701  if (moi->pos > ooi->pos)
 702   return 0;
 703
 704  if (moi->pos == ooi->pos)
 705   return moi->len == ooi->len && !memcmp(moi->buf, ooi->buf, moi->len);
 706
 707  return 1;
 708 }
 709
 710 STATIC OP *(*indirect_old_ck_entersub)(pTHX_ OP *) = 0;
 711
 712 STATIC OP *indirect_ck_entersub(pTHX_ OP *o) {
 713  SV *code = indirect_hint();
 714
 715  o = CALL_FPTR(indirect_old_ck_entersub)(aTHX_ o);
 716
 717  if (code) {
 718   const indirect_op_info_t *moi, *ooi;
 719   OP     *mop, *oop;
 720   LISTOP *lop;
 721
 722   oop = o;
 723   do {
 724    lop = (LISTOP *) oop;
 725    if (!(lop->op_flags & OPf_KIDS))
 726     goto done;
 727    oop = lop->op_first;
 728   } while (oop->op_type != OP_PUSHMARK);
 729   oop = oop->op_sibling;
 730   mop = lop->op_last;
 731
 732   if (!oop)
 733    goto done;
 734
 735   switch (oop->op_type) {
 736    case OP_CONST:
 737    case OP_RV2SV:
 738    case OP_PADSV:
 739    case OP_SCOPE:
 740    case OP_LEAVE:
 741     break;
 742    default:
 743     goto done;
 744   }
 745
 746   if (mop->op_type == OP_METHOD)
 747    mop = cUNOPx(mop)->op_first;
 748   else if (mop->op_type != OP_METHOD_NAMED)
 749    goto done;
 750
 751   moi = indirect_map_fetch(mop);
 752   if (!moi)
 753    goto done;
 754
 755   ooi = indirect_map_fetch(oop);
 756   if (!ooi)
 757    goto done;
 758
 759   if (indirect_is_indirect(moi, ooi)) {
 760    SV *file;
 761    dSP;
 762
 763    ENTER;
 764    SAVETMPS;
 765
 766 #ifdef USE_ITHREADS
 767    file = sv_2mortal(newSVpv(CopFILE(&PL_compiling), 0));
 768 #else
 769    file = sv_mortalcopy(CopFILESV(&PL_compiling));
 770 #endif
 771
 772    PUSHMARK(SP);
 773    EXTEND(SP, 4);
 774    mPUSHp(ooi->buf, ooi->len);
 775    mPUSHp(moi->buf, moi->len);
 776    PUSHs(file);
 777    mPUSHu(moi->line);
 778    PUTBACK;
 779
 780    call_sv(code, G_VOID);
 781
 782    PUTBACK;
 783
 784    FREETMPS;
 785    LEAVE;
 786   }
 787  }
 788
 789 done:
 790  return o;
 791 }
 792
 793 STATIC U32 indirect_initialized = 0;
 794
 795 STATIC void indirect_teardown(pTHX_ void *root) {
 796  dMY_CXT;
 797
 798  if (!indirect_initialized)
 799   return;
 800
 801 #if I_MULTIPLICITY
 802  if (aTHX != root)
 803   return;
 804 #endif
 805
 806  ptable_free(MY_CXT.map);
 807 #if I_THREADSAFE
 808  ptable_hints_free(MY_CXT.tbl);
 809 #endif
 810
 811  PL_check[OP_CONST]           = MEMBER_TO_FPTR(indirect_old_ck_const);
 812  indirect_old_ck_const        = 0;
 813  PL_check[OP_RV2SV]           = MEMBER_TO_FPTR(indirect_old_ck_rv2sv);
 814  indirect_old_ck_rv2sv        = 0;
 815  PL_check[OP_PADANY]          = MEMBER_TO_FPTR(indirect_old_ck_padany);
 816  indirect_old_ck_padany       = 0;
 817  PL_check[OP_SCOPE]           = MEMBER_TO_FPTR(indirect_old_ck_scope);
 818  indirect_old_ck_scope        = 0;
 819  PL_check[OP_LINESEQ]         = MEMBER_TO_FPTR(indirect_old_ck_lineseq);
 820  indirect_old_ck_lineseq      = 0;
 821
 822  PL_check[OP_METHOD]          = MEMBER_TO_FPTR(indirect_old_ck_method);
 823  indirect_old_ck_method       = 0;
 824  PL_check[OP_METHOD_NAMED]    = MEMBER_TO_FPTR(indirect_old_ck_method_named);
 825  indirect_old_ck_method_named = 0;
 826  PL_check[OP_ENTERSUB]        = MEMBER_TO_FPTR(indirect_old_ck_entersub);
 827  indirect_old_ck_entersub     = 0;
 828
 829  indirect_initialized = 0;
 830 }
 831
 832 STATIC void indirect_setup(pTHX) {
 833 #define indirect_setup() indirect_setup(aTHX)
 834  if (indirect_initialized)
 835   return;
 836
 837  {
 838   MY_CXT_INIT;
 839 #if I_THREADSAFE
 840   MY_CXT.tbl   = ptable_new();
 841   MY_CXT.owner = aTHX;
 842 #endif
 843   MY_CXT.map   = ptable_new();
 844  }
 845
 846  indirect_old_ck_const        = PL_check[OP_CONST];
 847  PL_check[OP_CONST]           = MEMBER_TO_FPTR(indirect_ck_const);
 848  indirect_old_ck_rv2sv        = PL_check[OP_RV2SV];
 849  PL_check[OP_RV2SV]           = MEMBER_TO_FPTR(indirect_ck_rv2sv);
 850  indirect_old_ck_padany       = PL_check[OP_PADANY];
 851  PL_check[OP_PADANY]          = MEMBER_TO_FPTR(indirect_ck_padany);
 852  indirect_old_ck_scope        = PL_check[OP_SCOPE];
 853  PL_check[OP_SCOPE]           = MEMBER_TO_FPTR(indirect_ck_scope);
 854  indirect_old_ck_lineseq      = PL_check[OP_LINESEQ];
 855  PL_check[OP_LINESEQ]         = MEMBER_TO_FPTR(indirect_ck_scope);
 856
 857  indirect_old_ck_method       = PL_check[OP_METHOD];
 858  PL_check[OP_METHOD]          = MEMBER_TO_FPTR(indirect_ck_method);
 859  indirect_old_ck_method_named = PL_check[OP_METHOD_NAMED];
 860  PL_check[OP_METHOD_NAMED]    = MEMBER_TO_FPTR(indirect_ck_method_named);
 861  indirect_old_ck_entersub     = PL_check[OP_ENTERSUB];
 862  PL_check[OP_ENTERSUB]        = MEMBER_TO_FPTR(indirect_ck_entersub);
 863
 864 #if I_MULTIPLICITY
 865  call_atexit(indirect_teardown, aTHX);
 866 #else
 867  call_atexit(indirect_teardown, NULL);
 868 #endif
 869
 870  indirect_initialized = 1;
 871 }
 872
 873 STATIC U32 indirect_booted = 0;
 874
 875 /* --- XS ------------------------------------------------------------------ */
 876
 877 MODULE = indirect      PACKAGE = indirect
 878
 879 PROTOTYPES: ENABLE
 880
 881 BOOT:
 882 {
 883  if (!indirect_booted++) {
 884   HV *stash;
 885
 886   PERL_HASH(indirect_hash, __PACKAGE__, __PACKAGE_LEN__);
 887
 888   stash = gv_stashpvn(__PACKAGE__, __PACKAGE_LEN__, 1);
 889   newCONSTSUB(stash, "I_THREADSAFE", newSVuv(I_THREADSAFE));
 890   newCONSTSUB(stash, "I_FORKSAFE",   newSVuv(I_FORKSAFE));
 891  }
 892
 893  indirect_setup();
 894 }
 895
 896 #if I_THREADSAFE
 897
 898 void
 899 CLONE(...)
 900 PROTOTYPE: DISABLE
 901 PREINIT:
 902  ptable *t;
 903 PPCODE:
 904  {
 905   my_cxt_t ud;
 906   dMY_CXT;
 907   ud.tbl   = t = ptable_new();
 908   ud.owner = MY_CXT.owner;
 909   ptable_walk(MY_CXT.tbl, indirect_ptable_clone, &ud);
 910  }
 911  {
 912   MY_CXT_CLONE;
 913   MY_CXT.map   = ptable_new();
 914   MY_CXT.tbl   = t;
 915   MY_CXT.owner = aTHX;
 916  }
 917  reap(3, indirect_thread_cleanup, NULL);
 918  XSRETURN(0);
 919
 920 #endif
 921
 922 SV *
 923 _tag(SV *value)
 924 PROTOTYPE: $
 925 CODE:
 926  RETVAL = indirect_tag(value);
 927 OUTPUT:
 928  RETVAL