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, 10, 1)
  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_delete(T, K)   ptable_delete(aTHX_ (T), (K))
 204 #define ptable_clear(T)       ptable_clear(aTHX_ (T))
 205 #define ptable_free(T)        ptable_free(aTHX_ (T))
 206
 207 #define MY_CXT_KEY __PACKAGE__ "::_guts" XS_VERSION
 208
 209 typedef struct {
 210 #if I_THREADSAFE
 211  ptable *tbl; /* It really is a ptable_hints */
 212  tTHX    owner;
 213 #endif
 214  ptable *map;
 215 } my_cxt_t;
 216
 217 START_MY_CXT
 218
 219 #if I_THREADSAFE
 220
 221 STATIC SV *indirect_clone(pTHX_ SV *sv, tTHX owner) {
 222 #define indirect_clone(S, O) indirect_clone(aTHX_ (S), (O))
 223  CLONE_PARAMS  param;
 224  AV           *stashes = NULL;
 225  SV           *dupsv;
 226
 227  if (SvTYPE(sv) == SVt_PVHV && HvNAME_get(sv))
 228   stashes = newAV();
 229
 230  param.stashes    = stashes;
 231  param.flags      = 0;
 232  param.proto_perl = owner;
 233
 234  dupsv = sv_dup(sv, &param);
 235
 236  if (stashes) {
 237   av_undef(stashes);
 238   SvREFCNT_dec(stashes);
 239  }
 240
 241  return SvREFCNT_inc(dupsv);
 242 }
 243
 244 STATIC void indirect_ptable_clone(pTHX_ ptable_ent *ent, void *ud_) {
 245  my_cxt_t        *ud = ud_;
 246  indirect_hint_t *h1 = ent->val;
 247  indirect_hint_t *h2;
 248
 249  if (ud->owner == aTHX)
 250   return;
 251
 252 #if I_HINT_STRUCT
 253
 254  h2       = PerlMemShared_malloc(sizeof *h2);
 255  h2->code = indirect_clone(h1->code, ud->owner);
 256  SvREFCNT_inc(h2->code);
 257 #if I_WORKAROUND_REQUIRE_PROPAGATION
 258  h2->require_tag = PTR2IV(indirect_clone(INT2PTR(SV *, h1->require_tag),
 259                                          ud->owner));
 260 #endif
 261
 262 #else  /*  I_HINT_STRUCT */
 263
 264  h2 = indirect_clone(h1, ud->owner);
 265  SvREFCNT_inc(h2);
 266
 267 #endif /* !I_HINT_STRUCT */
 268
 269  ptable_hints_store(ud->tbl, ent->key, h2);
 270 }
 271
 272 #include "reap.h"
 273
 274 STATIC void indirect_thread_cleanup(pTHX_ void *ud) {
 275  dMY_CXT;
 276
 277  ptable_free(MY_CXT.map);
 278  ptable_hints_free(MY_CXT.tbl);
 279 }
 280
 281 #endif /* I_THREADSAFE */
 282
 283 #if I_WORKAROUND_REQUIRE_PROPAGATION
 284 STATIC IV indirect_require_tag(pTHX) {
 285 #define indirect_require_tag() indirect_require_tag(aTHX)
 286  const CV *cv, *outside;
 287
 288  cv = PL_compcv;
 289
 290  if (!cv) {
 291   /* If for some reason the pragma is operational at run-time, try to discover
 292    * the current cv in use. */
 293   const PERL_SI *si;
 294
 295   for (si = PL_curstackinfo; si; si = si->si_prev) {
 296    I32 cxix;
 297
 298    for (cxix = si->si_cxix; cxix >= 0; --cxix) {
 299     const PERL_CONTEXT *cx = si->si_cxstack + cxix;
 300
 301     switch (CxTYPE(cx)) {
 302      case CXt_SUB:
 303      case CXt_FORMAT:
 304       /* The propagation workaround is only needed up to 5.10.0 and at that
 305        * time format and sub contexts were still identical. And even later the
 306        * cv members offsets should have been kept the same. */
 307       cv = cx->blk_sub.cv;
 308       goto get_enclosing_cv;
 309      case CXt_EVAL:
 310       cv = cx->blk_eval.cv;
 311       goto get_enclosing_cv;
 312      default:
 313       break;
 314     }
 315    }
 316   }
 317
 318   cv = PL_main_cv;
 319  }
 320
 321 get_enclosing_cv:
 322  for (outside = CvOUTSIDE(cv); outside; outside = CvOUTSIDE(cv))
 323   cv = outside;
 324
 325  return PTR2IV(cv);
 326 }
 327 #endif /* I_WORKAROUND_REQUIRE_PROPAGATION */
 328
 329 STATIC SV *indirect_tag(pTHX_ SV *value) {
 330 #define indirect_tag(V) indirect_tag(aTHX_ (V))
 331  indirect_hint_t *h;
 332  SV *code = NULL;
 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  {
 354   dMY_CXT;
 355   /* We only need for the key to be an unique tag for looking up the value later
 356    * Allocated memory provides convenient unique identifiers, so that's why we
 357    * use the hint as the key itself. */
 358   ptable_hints_store(MY_CXT.tbl, h, h);
 359  }
 360 #endif /* I_THREADSAFE */
 361
 362  return newSViv(PTR2IV(h));
 363 }
 364
 365 STATIC SV *indirect_detag(pTHX_ const SV *hint) {
 366 #define indirect_detag(H) indirect_detag(aTHX_ (H))
 367  indirect_hint_t *h;
 368
 369  if (!(hint && SvIOK(hint)))
 370   return NULL;
 371
 372  h = INT2PTR(indirect_hint_t *, SvIVX(hint));
 373 #if I_THREADSAFE
 374  {
 375   dMY_CXT;
 376   h = ptable_fetch(MY_CXT.tbl, h);
 377  }
 378 #endif /* I_THREADSAFE */
 379
 380 #if I_WORKAROUND_REQUIRE_PROPAGATION
 381  if (indirect_require_tag() != h->require_tag)
 382   return NULL;
 383 #endif /* I_WORKAROUND_REQUIRE_PROPAGATION */
 384
 385  return I_HINT_CODE(h);
 386 }
 387
 388 STATIC U32 indirect_hash = 0;
 389
 390 STATIC SV *indirect_hint(pTHX) {
 391 #define indirect_hint() indirect_hint(aTHX)
 392  SV *hint;
 393
 394  if (IN_PERL_RUNTIME)
 395   return NULL;
 396
 397 #ifdef cop_hints_fetch_pvn
 398  hint = cop_hints_fetch_pvn(PL_curcop, __PACKAGE__, __PACKAGE_LEN__,
 399                                                               indirect_hash, 0);
 400 #elif I_HAS_PERL(5, 9, 5)
 401  hint = Perl_refcounted_he_fetch(aTHX_ PL_curcop->cop_hints_hash,
 402                                        NULL,
 403                                        __PACKAGE__, __PACKAGE_LEN__,
 404                                        0,
 405                                        indirect_hash);
 406 #else
 407  {
 408   SV **val = hv_fetch(GvHV(PL_hintgv), __PACKAGE__, __PACKAGE_LEN__, 0);
 409   if (!val)
 410    return 0;
 411   hint = *val;
 412  }
 413 #endif
 414
 415  return indirect_detag(hint);
 416 }
 417
 418 /* ... op -> source position ............................................... */
 419
 420 STATIC void indirect_map_store(pTHX_ const OP *o, STRLEN pos, SV *sv, line_t line) {
 421 #define indirect_map_store(O, P, N, L) indirect_map_store(aTHX_ (O), (P), (N), (L))
 422  indirect_op_info_t *oi;
 423  const char *s;
 424  STRLEN len;
 425  dMY_CXT;
 426
 427  if (!(oi = ptable_fetch(MY_CXT.map, o))) {
 428   Newx(oi, 1, indirect_op_info_t);
 429   ptable_store(MY_CXT.map, o, oi);
 430   oi->buf  = NULL;
 431   oi->size = 0;
 432  }
 433
 434  if (sv) {
 435   s = SvPV_const(sv, len);
 436  } else {
 437   s   = "{";
 438   len = 1;
 439  }
 440
 441  if (len > oi->size) {
 442   Safefree(oi->buf);
 443   Newx(oi->buf, len, char);
 444   oi->size = len;
 445  }
 446  Copy(s, oi->buf, len, char);
 447
 448  oi->len  = len;
 449  oi->pos  = pos;
 450  oi->line = line;
 451 }
 452
 453 STATIC const indirect_op_info_t *indirect_map_fetch(pTHX_ const OP *o) {
 454 #define indirect_map_fetch(O) indirect_map_fetch(aTHX_ (O))
 455  dMY_CXT;
 456
 457  return ptable_fetch(MY_CXT.map, o);
 458 }
 459
 460 STATIC void indirect_map_delete(pTHX_ const OP *o) {
 461 #define indirect_map_delete(O) indirect_map_delete(aTHX_ (O))
 462  dMY_CXT;
 463
 464  ptable_delete(MY_CXT.map, o);
 465 }
 466
 467 /* --- Check functions ----------------------------------------------------- */
 468
 469 STATIC int indirect_find(pTHX_ SV *sv, const char *s, STRLEN *pos) {
 470 #define indirect_find(N, S, P) indirect_find(aTHX_ (N), (S), (P))
 471  STRLEN len;
 472  const char *p, *r = SvPV_const(sv, len);
 473
 474  if (len >= 1 && *r == '$') {
 475   ++r;
 476   --len;
 477   s = strchr(s, '$');
 478   if (!s)
 479    return 0;
 480  }
 481
 482  p = s;
 483  while (1) {
 484   p = strstr(p, r);
 485   if (!p)
 486    return 0;
 487   if (!isALNUM(p[len]))
 488    break;
 489   /* p points to a word that has r as prefix, skip the rest of the word */
 490   p += len + 1;
 491   while (isALNUM(*p))
 492    ++p;
 493  }
 494
 495  *pos = p - SvPVX_const(PL_linestr);
 496
 497  return 1;
 498 }
 499
 500 /* ... ck_const ............................................................ */
 501
 502 STATIC OP *(*indirect_old_ck_const)(pTHX_ OP *) = 0;
 503
 504 STATIC OP *indirect_ck_const(pTHX_ OP *o) {
 505  o = indirect_old_ck_const(aTHX_ o);
 506
 507  if (indirect_hint()) {
 508   SV *sv = cSVOPo_sv;
 509
 510   if (SvPOK(sv) && (SvTYPE(sv) >= SVt_PV)) {
 511    STRLEN pos;
 512
 513    if (indirect_find(sv, PL_oldbufptr, &pos)) {
 514     indirect_map_store(o, pos, sv, CopLINE(&PL_compiling));
 515     return o;
 516    }
 517   }
 518  }
 519
 520  indirect_map_delete(o);
 521  return o;
 522 }
 523
 524 /* ... ck_rv2sv ............................................................ */
 525
 526 STATIC OP *(*indirect_old_ck_rv2sv)(pTHX_ OP *) = 0;
 527
 528 STATIC OP *indirect_ck_rv2sv(pTHX_ OP *o) {
 529  if (indirect_hint()) {
 530   OP *op = cUNOPo->op_first;
 531   SV *sv;
 532   const char *name = NULL;
 533   STRLEN pos, len;
 534   OPCODE type = (OPCODE) op->op_type;
 535
 536   switch (type) {
 537    case OP_GV:
 538    case OP_GVSV: {
 539     GV *gv = cGVOPx_gv(op);
 540     name = GvNAME(gv);
 541     len  = GvNAMELEN(gv);
 542     break;
 543    }
 544    default:
 545     if ((PL_opargs[type] & OA_CLASS_MASK) == OA_SVOP) {
 546      SV *nsv = cSVOPx_sv(op);
 547      if (SvPOK(nsv) && (SvTYPE(nsv) >= SVt_PV))
 548       name = SvPV_const(nsv, len);
 549     }
 550   }
 551   if (!name)
 552    goto done;
 553
 554   sv = sv_2mortal(newSVpvn("$", 1));
 555   sv_catpvn_nomg(sv, name, len);
 556   if (!indirect_find(sv, PL_oldbufptr, &pos)) {
 557    /* If it failed, retry without the current stash */
 558    const char *stash = HvNAME_get(PL_curstash);
 559    STRLEN stashlen = HvNAMELEN_get(PL_curstash);
 560
 561    if ((len < stashlen + 2) || strnNE(name, stash, stashlen)
 562        || name[stashlen] != ':' || name[stashlen+1] != ':') {
 563     /* Failed again ? Try to remove main */
 564     stash = "main";
 565     stashlen = 4;
 566     if ((len < stashlen + 2) || strnNE(name, stash, stashlen)
 567         || name[stashlen] != ':' || name[stashlen+1] != ':')
 568      goto done;
 569    }
 570
 571    sv_setpvn(sv, "$", 1);
 572    stashlen += 2;
 573    sv_catpvn_nomg(sv, name + stashlen, len - stashlen);
 574    if (!indirect_find(sv, PL_oldbufptr, &pos))
 575     goto done;
 576   }
 577
 578   o = indirect_old_ck_rv2sv(aTHX_ o);
 579
 580   indirect_map_store(o, pos, sv, CopLINE(&PL_compiling));
 581   return o;
 582  }
 583
 584 done:
 585  o = indirect_old_ck_rv2sv(aTHX_ o);
 586
 587  indirect_map_delete(o);
 588  return o;
 589 }
 590
 591 /* ... ck_padany ........................................................... */
 592
 593 STATIC OP *(*indirect_old_ck_padany)(pTHX_ OP *) = 0;
 594
 595 STATIC OP *indirect_ck_padany(pTHX_ OP *o) {
 596  o = indirect_old_ck_padany(aTHX_ o);
 597
 598  if (indirect_hint()) {
 599   SV *sv;
 600   const char *s = PL_oldbufptr, *t = PL_bufptr - 1;
 601
 602   while (s < t && isSPACE(*s)) ++s;
 603   if (*s == '$' && ++s <= t) {
 604    while (s < t && isSPACE(*s)) ++s;
 605    while (s < t && isSPACE(*t)) --t;
 606    sv = sv_2mortal(newSVpvn("$", 1));
 607    sv_catpvn_nomg(sv, s, t - s + 1);
 608    indirect_map_store(o, s - SvPVX_const(PL_linestr),
 609                          sv, CopLINE(&PL_compiling));
 610    return o;
 611   }
 612  }
 613
 614  indirect_map_delete(o);
 615  return o;
 616 }
 617
 618 /* ... ck_scope ............................................................ */
 619
 620 STATIC OP *(*indirect_old_ck_scope)  (pTHX_ OP *) = 0;
 621 STATIC OP *(*indirect_old_ck_lineseq)(pTHX_ OP *) = 0;
 622
 623 STATIC OP *indirect_ck_scope(pTHX_ OP *o) {
 624  OP *(*old_ck)(pTHX_ OP *) = 0;
 625
 626  switch (o->op_type) {
 627   case OP_SCOPE:   old_ck = indirect_old_ck_scope;   break;
 628   case OP_LINESEQ: old_ck = indirect_old_ck_lineseq; break;
 629  }
 630  o = old_ck(aTHX_ o);
 631
 632  if (indirect_hint()) {
 633   indirect_map_store(o, PL_oldbufptr - SvPVX_const(PL_linestr),
 634                         NULL, CopLINE(&PL_compiling));
 635   return o;
 636  }
 637
 638  indirect_map_delete(o);
 639  return o;
 640 }
 641
 642 /* We don't need to clean the map entries for leave ops because they can only
 643  * be created by mutating from a lineseq. */
 644
 645 /* ... ck_method ........................................................... */
 646
 647 STATIC OP *(*indirect_old_ck_method)(pTHX_ OP *) = 0;
 648
 649 STATIC OP *indirect_ck_method(pTHX_ OP *o) {
 650  if (indirect_hint()) {
 651   OP *op = cUNOPo->op_first;
 652
 653   /* Indirect method call is only possible when the method is a bareword, so
 654    * don't trip up on $obj->$meth. */
 655   if (op && op->op_type == OP_CONST) {
 656    const indirect_op_info_t *oi = indirect_map_fetch(op);
 657    STRLEN pos;
 658    line_t line;
 659    SV *sv;
 660
 661    if (!oi)
 662     goto done;
 663
 664    sv   = sv_2mortal(newSVpvn(oi->buf, oi->len));
 665    pos  = oi->pos;
 666    /* Keep the old line so that we really point to the first line of the
 667     * expression. */
 668    line = oi->line;
 669
 670    o = indirect_old_ck_method(aTHX_ o);
 671    /* o may now be a method_named */
 672
 673    indirect_map_store(o, pos, sv, line);
 674    return o;
 675   }
 676  }
 677
 678 done:
 679  o = indirect_old_ck_method(aTHX_ o);
 680
 681  indirect_map_delete(o);
 682  return o;
 683 }
 684
 685 /* ... ck_method_named ..................................................... */
 686
 687 /* "use foo/no foo" compiles its call to import/unimport directly to a
 688  * method_named op. */
 689
 690 STATIC OP *(*indirect_old_ck_method_named)(pTHX_ OP *) = 0;
 691
 692 STATIC OP *indirect_ck_method_named(pTHX_ OP *o) {
 693  if (indirect_hint()) {
 694   STRLEN pos;
 695   line_t line;
 696   SV *sv;
 697
 698   sv = cSVOPo_sv;
 699   if (!SvPOK(sv) || (SvTYPE(sv) < SVt_PV))
 700    goto done;
 701   sv = sv_mortalcopy(sv);
 702
 703   if (!indirect_find(sv, PL_oldbufptr, &pos))
 704    goto done;
 705   line = CopLINE(&PL_compiling);
 706
 707   o = indirect_old_ck_method_named(aTHX_ o);
 708
 709   indirect_map_store(o, pos, sv, line);
 710   return o;
 711  }
 712
 713 done:
 714  o = indirect_old_ck_method_named(aTHX_ o);
 715
 716  indirect_map_delete(o);
 717  return o;
 718 }
 719
 720 /* ... ck_entersub ......................................................... */
 721
 722 STATIC OP *(*indirect_old_ck_entersub)(pTHX_ OP *) = 0;
 723
 724 STATIC OP *indirect_ck_entersub(pTHX_ OP *o) {
 725  SV *code = indirect_hint();
 726
 727  o = indirect_old_ck_entersub(aTHX_ o);
 728
 729  if (code) {
 730   const indirect_op_info_t *moi, *ooi;
 731   OP     *mop, *oop;
 732   LISTOP *lop;
 733
 734   oop = o;
 735   do {
 736    lop = (LISTOP *) oop;
 737    if (!(lop->op_flags & OPf_KIDS))
 738     goto done;
 739    oop = lop->op_first;
 740   } while (oop->op_type != OP_PUSHMARK);
 741   oop = oop->op_sibling;
 742   mop = lop->op_last;
 743
 744   if (!oop)
 745    goto done;
 746
 747   switch (oop->op_type) {
 748    case OP_CONST:
 749    case OP_RV2SV:
 750    case OP_PADSV:
 751    case OP_SCOPE:
 752    case OP_LEAVE:
 753     break;
 754    default:
 755     goto done;
 756   }
 757
 758   if (mop->op_type == OP_METHOD)
 759    mop = cUNOPx(mop)->op_first;
 760   else if (mop->op_type != OP_METHOD_NAMED)
 761    goto done;
 762
 763   moi = indirect_map_fetch(mop);
 764   if (!moi)
 765    goto done;
 766
 767   ooi = indirect_map_fetch(oop);
 768   if (!ooi)
 769    goto done;
 770
 771   /* When positions are identical, the method and the object must have the
 772    * same name. But it also means that it is an indirect call, as "foo->foo"
 773    * results in different positions. */
 774   if (moi->pos <= ooi->pos) {
 775    SV *file;
 776    dSP;
 777
 778    ENTER;
 779    SAVETMPS;
 780
 781 #ifdef USE_ITHREADS
 782    file = sv_2mortal(newSVpv(CopFILE(&PL_compiling), 0));
 783 #else
 784    file = sv_mortalcopy(CopFILESV(&PL_compiling));
 785 #endif
 786
 787    PUSHMARK(SP);
 788    EXTEND(SP, 4);
 789    mPUSHp(ooi->buf, ooi->len);
 790    mPUSHp(moi->buf, moi->len);
 791    PUSHs(file);
 792    mPUSHu(moi->line);
 793    PUTBACK;
 794
 795    call_sv(code, G_VOID);
 796
 797    PUTBACK;
 798
 799    FREETMPS;
 800    LEAVE;
 801   }
 802  }
 803
 804 done:
 805  return o;
 806 }
 807
 808 STATIC U32 indirect_initialized = 0;
 809
 810 STATIC void indirect_teardown(pTHX_ void *root) {
 811  if (!indirect_initialized)
 812   return;
 813
 814 #if I_MULTIPLICITY
 815  if (aTHX != root)
 816   return;
 817 #endif
 818
 819  {
 820   dMY_CXT;
 821   ptable_free(MY_CXT.map);
 822 #if I_THREADSAFE
 823   ptable_hints_free(MY_CXT.tbl);
 824 #endif
 825  }
 826
 827  PL_check[OP_CONST]           = MEMBER_TO_FPTR(indirect_old_ck_const);
 828  indirect_old_ck_const        = 0;
 829  PL_check[OP_RV2SV]           = MEMBER_TO_FPTR(indirect_old_ck_rv2sv);
 830  indirect_old_ck_rv2sv        = 0;
 831  PL_check[OP_PADANY]          = MEMBER_TO_FPTR(indirect_old_ck_padany);
 832  indirect_old_ck_padany       = 0;
 833  PL_check[OP_SCOPE]           = MEMBER_TO_FPTR(indirect_old_ck_scope);
 834  indirect_old_ck_scope        = 0;
 835  PL_check[OP_LINESEQ]         = MEMBER_TO_FPTR(indirect_old_ck_lineseq);
 836  indirect_old_ck_lineseq      = 0;
 837
 838  PL_check[OP_METHOD]          = MEMBER_TO_FPTR(indirect_old_ck_method);
 839  indirect_old_ck_method       = 0;
 840  PL_check[OP_METHOD_NAMED]    = MEMBER_TO_FPTR(indirect_old_ck_method_named);
 841  indirect_old_ck_method_named = 0;
 842  PL_check[OP_ENTERSUB]        = MEMBER_TO_FPTR(indirect_old_ck_entersub);
 843  indirect_old_ck_entersub     = 0;
 844
 845  indirect_initialized = 0;
 846 }
 847
 848 STATIC void indirect_setup(pTHX) {
 849 #define indirect_setup() indirect_setup(aTHX)
 850  if (indirect_initialized)
 851   return;
 852
 853  {
 854   MY_CXT_INIT;
 855 #if I_THREADSAFE
 856   MY_CXT.tbl   = ptable_new();
 857   MY_CXT.owner = aTHX;
 858 #endif
 859   MY_CXT.map   = ptable_new();
 860  }
 861
 862  indirect_old_ck_const        = PL_check[OP_CONST];
 863  PL_check[OP_CONST]           = MEMBER_TO_FPTR(indirect_ck_const);
 864  indirect_old_ck_rv2sv        = PL_check[OP_RV2SV];
 865  PL_check[OP_RV2SV]           = MEMBER_TO_FPTR(indirect_ck_rv2sv);
 866  indirect_old_ck_padany       = PL_check[OP_PADANY];
 867  PL_check[OP_PADANY]          = MEMBER_TO_FPTR(indirect_ck_padany);
 868  indirect_old_ck_scope        = PL_check[OP_SCOPE];
 869  PL_check[OP_SCOPE]           = MEMBER_TO_FPTR(indirect_ck_scope);
 870  indirect_old_ck_lineseq      = PL_check[OP_LINESEQ];
 871  PL_check[OP_LINESEQ]         = MEMBER_TO_FPTR(indirect_ck_scope);
 872
 873  indirect_old_ck_method       = PL_check[OP_METHOD];
 874  PL_check[OP_METHOD]          = MEMBER_TO_FPTR(indirect_ck_method);
 875  indirect_old_ck_method_named = PL_check[OP_METHOD_NAMED];
 876  PL_check[OP_METHOD_NAMED]    = MEMBER_TO_FPTR(indirect_ck_method_named);
 877  indirect_old_ck_entersub     = PL_check[OP_ENTERSUB];
 878  PL_check[OP_ENTERSUB]        = MEMBER_TO_FPTR(indirect_ck_entersub);
 879
 880 #if I_MULTIPLICITY
 881  call_atexit(indirect_teardown, aTHX);
 882 #else
 883  call_atexit(indirect_teardown, NULL);
 884 #endif
 885
 886  indirect_initialized = 1;
 887 }
 888
 889 STATIC U32 indirect_booted = 0;
 890
 891 /* --- XS ------------------------------------------------------------------ */
 892
 893 MODULE = indirect      PACKAGE = indirect
 894
 895 PROTOTYPES: ENABLE
 896
 897 BOOT:
 898 {
 899  if (!indirect_booted++) {
 900   HV *stash;
 901
 902   PERL_HASH(indirect_hash, __PACKAGE__, __PACKAGE_LEN__);
 903
 904   stash = gv_stashpvn(__PACKAGE__, __PACKAGE_LEN__, 1);
 905   newCONSTSUB(stash, "I_THREADSAFE", newSVuv(I_THREADSAFE));
 906   newCONSTSUB(stash, "I_FORKSAFE",   newSVuv(I_FORKSAFE));
 907  }
 908
 909  indirect_setup();
 910 }
 911
 912 #if I_THREADSAFE
 913
 914 void
 915 CLONE(...)
 916 PROTOTYPE: DISABLE
 917 PREINIT:
 918  ptable *t;
 919 PPCODE:
 920  {
 921   my_cxt_t ud;
 922   dMY_CXT;
 923   ud.tbl   = t = ptable_new();
 924   ud.owner = MY_CXT.owner;
 925   ptable_walk(MY_CXT.tbl, indirect_ptable_clone, &ud);
 926  }
 927  {
 928   MY_CXT_CLONE;
 929   MY_CXT.map   = ptable_new();
 930   MY_CXT.tbl   = t;
 931   MY_CXT.owner = aTHX;
 932  }
 933  reap(3, indirect_thread_cleanup, NULL);
 934  XSRETURN(0);
 935
 936 #endif
 937
 938 SV *
 939 _tag(SV *value)
 940 PROTOTYPE: $
 941 CODE:
 942  RETVAL = indirect_tag(value);
 943 OUTPUT:
 944  RETVAL