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_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 *hint;
 388
 389  if (IN_PERL_RUNTIME)
 390   return NULL;
 391
 392 #if I_HAS_PERL(5, 9, 5)
 393  hint = Perl_refcounted_he_fetch(aTHX_ PL_curcop->cop_hints_hash,
 394                                        NULL,
 395                                        __PACKAGE__, __PACKAGE_LEN__,
 396                                        0,
 397                                        indirect_hash);
 398 #else
 399  {
 400   SV **val = hv_fetch(GvHV(PL_hintgv), __PACKAGE__, __PACKAGE_LEN__,
 401                                                                  indirect_hash);
 402   if (!val)
 403    return 0;
 404   hint = *val;
 405  }
 406 #endif
 407  return indirect_detag(hint);
 408 }
 409
 410 /* ... op -> source position ............................................... */
 411
 412 STATIC void indirect_map_store(pTHX_ const OP *o, STRLEN pos, SV *sv, line_t line) {
 413 #define indirect_map_store(O, P, N, L) indirect_map_store(aTHX_ (O), (P), (N), (L))
 414  indirect_op_info_t *oi;
 415  const char *s;
 416  STRLEN len;
 417  dMY_CXT;
 418
 419  if (!(oi = ptable_fetch(MY_CXT.map, o))) {
 420   Newx(oi, 1, indirect_op_info_t);
 421   ptable_store(MY_CXT.map, o, oi);
 422   oi->buf  = NULL;
 423   oi->size = 0;
 424  }
 425
 426  if (sv) {
 427   s = SvPV_const(sv, len);
 428  } else {
 429   s   = "{";
 430   len = 1;
 431  }
 432
 433  if (len > oi->size) {
 434   Safefree(oi->buf);
 435   Newx(oi->buf, len, char);
 436   oi->size = len;
 437  }
 438  Copy(s, oi->buf, len, char);
 439
 440  oi->len  = len;
 441  oi->pos  = pos;
 442  oi->line = line;
 443 }
 444
 445 STATIC const indirect_op_info_t *indirect_map_fetch(pTHX_ const OP *o) {
 446 #define indirect_map_fetch(O) indirect_map_fetch(aTHX_ (O))
 447  dMY_CXT;
 448
 449  return ptable_fetch(MY_CXT.map, o);
 450 }
 451
 452 STATIC void indirect_map_delete(pTHX_ const OP *o) {
 453 #define indirect_map_delete(O) indirect_map_delete(aTHX_ (O))
 454  dMY_CXT;
 455
 456  ptable_store(MY_CXT.map, o, NULL);
 457 }
 458
 459 /* --- Check functions ----------------------------------------------------- */
 460
 461 STATIC int indirect_find(pTHX_ SV *sv, const char *s, STRLEN *pos) {
 462 #define indirect_find(N, S, P) indirect_find(aTHX_ (N), (S), (P))
 463  STRLEN len;
 464  const char *p = NULL, *r = SvPV_const(sv, len);
 465
 466  if (len >= 1 && *r == '$') {
 467   ++r;
 468   --len;
 469   s = strchr(s, '$');
 470   if (!s)
 471    return 0;
 472  }
 473
 474  p = strstr(s, r);
 475  while (p) {
 476   p += len;
 477   if (!isALNUM(*p))
 478    break;
 479   p = strstr(p + 1, r);
 480  }
 481  if (!p)
 482   return 0;
 483
 484  *pos = p - SvPVX_const(PL_linestr);
 485
 486  return 1;
 487 }
 488
 489 /* ... ck_const ............................................................ */
 490
 491 STATIC OP *(*indirect_old_ck_const)(pTHX_ OP *) = 0;
 492
 493 STATIC OP *indirect_ck_const(pTHX_ OP *o) {
 494  o = CALL_FPTR(indirect_old_ck_const)(aTHX_ o);
 495
 496  if (indirect_hint()) {
 497   SV *sv = cSVOPo_sv;
 498
 499   if (SvPOK(sv) && (SvTYPE(sv) >= SVt_PV)) {
 500    STRLEN pos;
 501
 502    if (indirect_find(sv, PL_oldbufptr, &pos)) {
 503     indirect_map_store(o, pos, sv, CopLINE(&PL_compiling));
 504     return o;
 505    }
 506   }
 507  }
 508
 509  indirect_map_delete(o);
 510  return o;
 511 }
 512
 513 /* ... ck_rv2sv ............................................................ */
 514
 515 STATIC OP *(*indirect_old_ck_rv2sv)(pTHX_ OP *) = 0;
 516
 517 STATIC OP *indirect_ck_rv2sv(pTHX_ OP *o) {
 518  if (indirect_hint()) {
 519   OP *op = cUNOPo->op_first;
 520   SV *sv;
 521   const char *name = NULL;
 522   STRLEN pos, len;
 523   OPCODE type = (OPCODE) op->op_type;
 524
 525   switch (type) {
 526    case OP_GV:
 527    case OP_GVSV: {
 528     GV *gv = cGVOPx_gv(op);
 529     name = GvNAME(gv);
 530     len  = GvNAMELEN(gv);
 531     break;
 532    }
 533    default:
 534     if ((PL_opargs[type] & OA_CLASS_MASK) == OA_SVOP) {
 535      SV *nsv = cSVOPx_sv(op);
 536      if (SvPOK(nsv) && (SvTYPE(nsv) >= SVt_PV))
 537       name = SvPV_const(nsv, len);
 538     }
 539   }
 540   if (!name)
 541    goto done;
 542
 543   sv = sv_2mortal(newSVpvn("$", 1));
 544   sv_catpvn_nomg(sv, name, len);
 545   if (!indirect_find(sv, PL_oldbufptr, &pos)) {
 546    /* If it failed, retry without the current stash */
 547    const char *stash = HvNAME_get(PL_curstash);
 548    STRLEN stashlen = HvNAMELEN_get(PL_curstash);
 549
 550    if ((len < stashlen + 2) || strnNE(name, stash, stashlen)
 551        || name[stashlen] != ':' || name[stashlen+1] != ':') {
 552     /* Failed again ? Try to remove main */
 553     stash = "main";
 554     stashlen = 4;
 555     if ((len < stashlen + 2) || strnNE(name, stash, stashlen)
 556         || name[stashlen] != ':' || name[stashlen+1] != ':')
 557      goto done;
 558    }
 559
 560    sv_setpvn(sv, "$", 1);
 561    stashlen += 2;
 562    sv_catpvn_nomg(sv, name + stashlen, len - stashlen);
 563    if (!indirect_find(sv, PL_oldbufptr, &pos))
 564     goto done;
 565   }
 566
 567   o = CALL_FPTR(indirect_old_ck_rv2sv)(aTHX_ o);
 568
 569   indirect_map_store(o, pos, sv, CopLINE(&PL_compiling));
 570   return o;
 571  }
 572
 573 done:
 574  o = CALL_FPTR(indirect_old_ck_rv2sv)(aTHX_ o);
 575
 576  indirect_map_delete(o);
 577  return o;
 578 }
 579
 580 /* ... ck_padany ........................................................... */
 581
 582 STATIC OP *(*indirect_old_ck_padany)(pTHX_ OP *) = 0;
 583
 584 STATIC OP *indirect_ck_padany(pTHX_ OP *o) {
 585  o = CALL_FPTR(indirect_old_ck_padany)(aTHX_ o);
 586
 587  if (indirect_hint()) {
 588   SV *sv;
 589   const char *s = PL_oldbufptr, *t = PL_bufptr - 1;
 590
 591   while (s < t && isSPACE(*s)) ++s;
 592   if (*s == '$' && ++s <= t) {
 593    while (s < t && isSPACE(*s)) ++s;
 594    while (s < t && isSPACE(*t)) --t;
 595    sv = sv_2mortal(newSVpvn("$", 1));
 596    sv_catpvn_nomg(sv, s, t - s + 1);
 597    indirect_map_store(o, s - SvPVX_const(PL_linestr),
 598                          sv, CopLINE(&PL_compiling));
 599    return o;
 600   }
 601  }
 602
 603  indirect_map_delete(o);
 604  return o;
 605 }
 606
 607 /* ... ck_scope ............................................................ */
 608
 609 STATIC OP *(*indirect_old_ck_scope)  (pTHX_ OP *) = 0;
 610 STATIC OP *(*indirect_old_ck_lineseq)(pTHX_ OP *) = 0;
 611
 612 STATIC OP *indirect_ck_scope(pTHX_ OP *o) {
 613  OP *(*old_ck)(pTHX_ OP *) = 0;
 614
 615  switch (o->op_type) {
 616   case OP_SCOPE:   old_ck = indirect_old_ck_scope;   break;
 617   case OP_LINESEQ: old_ck = indirect_old_ck_lineseq; break;
 618  }
 619  o = CALL_FPTR(old_ck)(aTHX_ o);
 620
 621  if (indirect_hint()) {
 622   indirect_map_store(o, PL_oldbufptr - SvPVX_const(PL_linestr),
 623                         NULL, CopLINE(&PL_compiling));
 624   return o;
 625  }
 626
 627  indirect_map_delete(o);
 628  return o;
 629 }
 630
 631 /* We don't need to clean the map entries for leave ops because they can only
 632  * be created by mutating from a lineseq. */
 633
 634 /* ... ck_method ........................................................... */
 635
 636 STATIC OP *(*indirect_old_ck_method)(pTHX_ OP *) = 0;
 637
 638 STATIC OP *indirect_ck_method(pTHX_ OP *o) {
 639  if (indirect_hint()) {
 640   OP *op = cUNOPo->op_first;
 641
 642   /* Indirect method call is only possible when the method is a bareword, so
 643    * don't trip up on $obj->$meth. */
 644   if (op && op->op_type == OP_CONST) {
 645    const indirect_op_info_t *oi = indirect_map_fetch(op);
 646    STRLEN pos;
 647    line_t line;
 648    SV *sv;
 649
 650    if (oi) {
 651     sv   = sv_2mortal(newSVpvn(oi->buf, oi->len));
 652     pos  = oi->pos;
 653     /* Keep the old line so that we really point to the first line of the
 654      * expression. */
 655     line = oi->line;
 656    } else {
 657     sv = cSVOPx_sv(op);
 658     if (!SvPOK(sv) || (SvTYPE(sv) < SVt_PV))
 659      goto done;
 660     sv = sv_mortalcopy(sv);
 661
 662     if (!indirect_find(sv, PL_oldbufptr, &pos))
 663      goto done;
 664     line = CopLINE(&PL_compiling);
 665    }
 666
 667    o = CALL_FPTR(indirect_old_ck_method)(aTHX_ o);
 668    /* o may now be a method_named */
 669
 670    indirect_map_store(o, pos, sv, line);
 671    return o;
 672   }
 673  }
 674
 675 done:
 676  o = CALL_FPTR(indirect_old_ck_method)(aTHX_ o);
 677
 678  indirect_map_delete(o);
 679  return o;
 680 }
 681
 682 /* ... ck_method_named ..................................................... */
 683
 684 /* "use foo/no foo" compiles its call to import/unimport directly to a
 685  * method_named op. */
 686
 687 STATIC OP *(*indirect_old_ck_method_named)(pTHX_ OP *) = 0;
 688
 689 STATIC OP *indirect_ck_method_named(pTHX_ OP *o) {
 690  if (indirect_hint()) {
 691   STRLEN pos;
 692   line_t line;
 693   SV *sv;
 694
 695   sv = cSVOPo_sv;
 696   if (!SvPOK(sv) || (SvTYPE(sv) < SVt_PV))
 697    goto done;
 698   sv = sv_mortalcopy(sv);
 699
 700   if (!indirect_find(sv, PL_oldbufptr, &pos))
 701    goto done;
 702   line = CopLINE(&PL_compiling);
 703
 704   o = CALL_FPTR(indirect_old_ck_method_named)(aTHX_ o);
 705
 706   indirect_map_store(o, pos, sv, line);
 707   return o;
 708  }
 709
 710 done:
 711  o = CALL_FPTR(indirect_old_ck_method_named)(aTHX_ o);
 712
 713  indirect_map_delete(o);
 714  return o;
 715 }
 716
 717 /* ... ck_entersub ......................................................... */
 718
 719 STATIC int indirect_is_indirect(const indirect_op_info_t *moi, const indirect_op_info_t *ooi) {
 720  if (moi->pos > ooi->pos)
 721   return 0;
 722
 723  if (moi->pos == ooi->pos)
 724   return moi->len == ooi->len && !memcmp(moi->buf, ooi->buf, moi->len);
 725
 726  return 1;
 727 }
 728
 729 STATIC OP *(*indirect_old_ck_entersub)(pTHX_ OP *) = 0;
 730
 731 STATIC OP *indirect_ck_entersub(pTHX_ OP *o) {
 732  SV *code = indirect_hint();
 733
 734  o = CALL_FPTR(indirect_old_ck_entersub)(aTHX_ o);
 735
 736  if (code) {
 737   const indirect_op_info_t *moi, *ooi;
 738   OP     *mop, *oop;
 739   LISTOP *lop;
 740
 741   oop = o;
 742   do {
 743    lop = (LISTOP *) oop;
 744    if (!(lop->op_flags & OPf_KIDS))
 745     goto done;
 746    oop = lop->op_first;
 747   } while (oop->op_type != OP_PUSHMARK);
 748   oop = oop->op_sibling;
 749   mop = lop->op_last;
 750
 751   if (!oop)
 752    goto done;
 753
 754   switch (oop->op_type) {
 755    case OP_CONST:
 756    case OP_RV2SV:
 757    case OP_PADSV:
 758    case OP_SCOPE:
 759    case OP_LEAVE:
 760     break;
 761    default:
 762     goto done;
 763   }
 764
 765   if (mop->op_type == OP_METHOD)
 766    mop = cUNOPx(mop)->op_first;
 767   else if (mop->op_type != OP_METHOD_NAMED)
 768    goto done;
 769
 770   moi = indirect_map_fetch(mop);
 771   if (!moi)
 772    goto done;
 773
 774   ooi = indirect_map_fetch(oop);
 775   if (!ooi)
 776    goto done;
 777
 778   if (indirect_is_indirect(moi, ooi)) {
 779    SV *file;
 780    dSP;
 781
 782    ENTER;
 783    SAVETMPS;
 784
 785 #ifdef USE_ITHREADS
 786    file = sv_2mortal(newSVpv(CopFILE(&PL_compiling), 0));
 787 #else
 788    file = sv_mortalcopy(CopFILESV(&PL_compiling));
 789 #endif
 790
 791    PUSHMARK(SP);
 792    EXTEND(SP, 4);
 793    mPUSHp(ooi->buf, ooi->len);
 794    mPUSHp(moi->buf, moi->len);
 795    PUSHs(file);
 796    mPUSHu(moi->line);
 797    PUTBACK;
 798
 799    call_sv(code, G_VOID);
 800
 801    PUTBACK;
 802
 803    FREETMPS;
 804    LEAVE;
 805   }
 806  }
 807
 808 done:
 809  return o;
 810 }
 811
 812 STATIC U32 indirect_initialized = 0;
 813
 814 STATIC void indirect_teardown(pTHX_ void *root) {
 815  dMY_CXT;
 816
 817  if (!indirect_initialized)
 818   return;
 819
 820 #if I_MULTIPLICITY
 821  if (aTHX != root)
 822   return;
 823 #endif
 824
 825  ptable_free(MY_CXT.map);
 826 #if I_THREADSAFE
 827  ptable_hints_free(MY_CXT.tbl);
 828 #endif
 829
 830  PL_check[OP_CONST]           = MEMBER_TO_FPTR(indirect_old_ck_const);
 831  indirect_old_ck_const        = 0;
 832  PL_check[OP_RV2SV]           = MEMBER_TO_FPTR(indirect_old_ck_rv2sv);
 833  indirect_old_ck_rv2sv        = 0;
 834  PL_check[OP_PADANY]          = MEMBER_TO_FPTR(indirect_old_ck_padany);
 835  indirect_old_ck_padany       = 0;
 836  PL_check[OP_SCOPE]           = MEMBER_TO_FPTR(indirect_old_ck_scope);
 837  indirect_old_ck_scope        = 0;
 838  PL_check[OP_LINESEQ]         = MEMBER_TO_FPTR(indirect_old_ck_lineseq);
 839  indirect_old_ck_lineseq      = 0;
 840
 841  PL_check[OP_METHOD]          = MEMBER_TO_FPTR(indirect_old_ck_method);
 842  indirect_old_ck_method       = 0;
 843  PL_check[OP_METHOD_NAMED]    = MEMBER_TO_FPTR(indirect_old_ck_method_named);
 844  indirect_old_ck_method_named = 0;
 845  PL_check[OP_ENTERSUB]        = MEMBER_TO_FPTR(indirect_old_ck_entersub);
 846  indirect_old_ck_entersub     = 0;
 847
 848  indirect_initialized = 0;
 849 }
 850
 851 STATIC void indirect_setup(pTHX) {
 852 #define indirect_setup() indirect_setup(aTHX)
 853  if (indirect_initialized)
 854   return;
 855
 856  {
 857   MY_CXT_INIT;
 858 #if I_THREADSAFE
 859   MY_CXT.tbl   = ptable_new();
 860   MY_CXT.owner = aTHX;
 861 #endif
 862   MY_CXT.map   = ptable_new();
 863  }
 864
 865  indirect_old_ck_const        = PL_check[OP_CONST];
 866  PL_check[OP_CONST]           = MEMBER_TO_FPTR(indirect_ck_const);
 867  indirect_old_ck_rv2sv        = PL_check[OP_RV2SV];
 868  PL_check[OP_RV2SV]           = MEMBER_TO_FPTR(indirect_ck_rv2sv);
 869  indirect_old_ck_padany       = PL_check[OP_PADANY];
 870  PL_check[OP_PADANY]          = MEMBER_TO_FPTR(indirect_ck_padany);
 871  indirect_old_ck_scope        = PL_check[OP_SCOPE];
 872  PL_check[OP_SCOPE]           = MEMBER_TO_FPTR(indirect_ck_scope);
 873  indirect_old_ck_lineseq      = PL_check[OP_LINESEQ];
 874  PL_check[OP_LINESEQ]         = MEMBER_TO_FPTR(indirect_ck_scope);
 875
 876  indirect_old_ck_method       = PL_check[OP_METHOD];
 877  PL_check[OP_METHOD]          = MEMBER_TO_FPTR(indirect_ck_method);
 878  indirect_old_ck_method_named = PL_check[OP_METHOD_NAMED];
 879  PL_check[OP_METHOD_NAMED]    = MEMBER_TO_FPTR(indirect_ck_method_named);
 880  indirect_old_ck_entersub     = PL_check[OP_ENTERSUB];
 881  PL_check[OP_ENTERSUB]        = MEMBER_TO_FPTR(indirect_ck_entersub);
 882
 883 #if I_MULTIPLICITY
 884  call_atexit(indirect_teardown, aTHX);
 885 #else
 886  call_atexit(indirect_teardown, NULL);
 887 #endif
 888
 889  indirect_initialized = 1;
 890 }
 891
 892 STATIC U32 indirect_booted = 0;
 893
 894 /* --- XS ------------------------------------------------------------------ */
 895
 896 MODULE = indirect      PACKAGE = indirect
 897
 898 PROTOTYPES: ENABLE
 899
 900 BOOT:
 901 {
 902  if (!indirect_booted++) {
 903   HV *stash;
 904
 905   PERL_HASH(indirect_hash, __PACKAGE__, __PACKAGE_LEN__);
 906
 907   stash = gv_stashpvn(__PACKAGE__, __PACKAGE_LEN__, 1);
 908   newCONSTSUB(stash, "I_THREADSAFE", newSVuv(I_THREADSAFE));
 909   newCONSTSUB(stash, "I_FORKSAFE",   newSVuv(I_FORKSAFE));
 910  }
 911
 912  indirect_setup();
 913 }
 914
 915 #if I_THREADSAFE
 916
 917 void
 918 CLONE(...)
 919 PROTOTYPE: DISABLE
 920 PREINIT:
 921  ptable *t;
 922 PPCODE:
 923  {
 924   my_cxt_t ud;
 925   dMY_CXT;
 926   ud.tbl   = t = ptable_new();
 927   ud.owner = MY_CXT.owner;
 928   ptable_walk(MY_CXT.tbl, indirect_ptable_clone, &ud);
 929  }
 930  {
 931   MY_CXT_CLONE;
 932   MY_CXT.map   = ptable_new();
 933   MY_CXT.tbl   = t;
 934   MY_CXT.owner = aTHX;
 935  }
 936  reap(3, indirect_thread_cleanup, NULL);
 937  XSRETURN(0);
 938
 939 #endif
 940
 941 SV *
 942 _tag(SV *value)
 943 PROTOTYPE: $
 944 CODE:
 945  RETVAL = indirect_tag(value);
 946 OUTPUT:
 947  RETVAL