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 #undef ENTERn
  65 #if defined(ENTER_with_name) && !I_HAS_PERL(5, 11, 4)
  66 # define ENTERn(N) ENTER_with_name(N)
  67 #else
  68 # define ENTERn(N) ENTER
  69 #endif
  70
  71 #undef LEAVEn
  72 #if defined(LEAVE_with_name) && !I_HAS_PERL(5, 11, 4)
  73 # define LEAVEn(N) LEAVE_with_name(N)
  74 #else
  75 # define LEAVEn(N) LEAVE
  76 #endif
  77
  78 #if I_HAS_PERL(5, 10, 0) || defined(PL_parser)
  79 # ifndef PL_lex_inwhat
  80 #  define PL_lex_inwhat PL_parser->lex_inwhat
  81 # endif
  82 # ifndef PL_linestr
  83 #  define PL_linestr PL_parser->linestr
  84 # endif
  85 # ifndef PL_bufptr
  86 #  define PL_bufptr PL_parser->bufptr
  87 # endif
  88 # ifndef PL_oldbufptr
  89 #  define PL_oldbufptr PL_parser->oldbufptr
  90 # endif
  91 #else
  92 # ifndef PL_lex_inwhat
  93 #  define PL_lex_inwhat PL_Ilex_inwhat
  94 # endif
  95 # ifndef PL_linestr
  96 #  define PL_linestr PL_Ilinestr
  97 # endif
  98 # ifndef PL_bufptr
  99 #  define PL_bufptr PL_Ibufptr
 100 # endif
 101 # ifndef PL_oldbufptr
 102 #  define PL_oldbufptr PL_Ioldbufptr
 103 # endif
 104 #endif
 105
 106 #ifndef I_WORKAROUND_REQUIRE_PROPAGATION
 107 # define I_WORKAROUND_REQUIRE_PROPAGATION !I_HAS_PERL(5, 10, 1)
 108 #endif
 109
 110 /* ... Thread safety and multiplicity ...................................... */
 111
 112 /* Safe unless stated otherwise in Makefile.PL */
 113 #ifndef I_FORKSAFE
 114 # define I_FORKSAFE 1
 115 #endif
 116
 117 #ifndef I_MULTIPLICITY
 118 # if defined(MULTIPLICITY) || defined(PERL_IMPLICIT_CONTEXT)
 119 #  define I_MULTIPLICITY 1
 120 # else
 121 #  define I_MULTIPLICITY 0
 122 # endif
 123 #endif
 124 #if I_MULTIPLICITY && !defined(tTHX)
 125 # define tTHX PerlInterpreter*
 126 #endif
 127
 128 #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))
 129 # define I_THREADSAFE 1
 130 # ifndef MY_CXT_CLONE
 131 #  define MY_CXT_CLONE \
 132     dMY_CXT_SV;                                                      \
 133     my_cxt_t *my_cxtp = (my_cxt_t*)SvPVX(newSV(sizeof(my_cxt_t)-1)); \
 134     Copy(INT2PTR(my_cxt_t*, SvUV(my_cxt_sv)), my_cxtp, 1, my_cxt_t); \
 135     sv_setuv(my_cxt_sv, PTR2UV(my_cxtp))
 136 # endif
 137 #else
 138 # define I_THREADSAFE 0
 139 # undef  dMY_CXT
 140 # define dMY_CXT      dNOOP
 141 # undef  MY_CXT
 142 # define MY_CXT       indirect_globaldata
 143 # undef  START_MY_CXT
 144 # define START_MY_CXT STATIC my_cxt_t MY_CXT;
 145 # undef  MY_CXT_INIT
 146 # define MY_CXT_INIT  NOOP
 147 # undef  MY_CXT_CLONE
 148 # define MY_CXT_CLONE NOOP
 149 #endif
 150
 151 /* --- Helpers ------------------------------------------------------------- */
 152
 153 /* ... Thread-safe hints ................................................... */
 154
 155 #if I_WORKAROUND_REQUIRE_PROPAGATION
 156
 157 typedef struct {
 158  SV *code;
 159  IV  require_tag;
 160 } indirect_hint_t;
 161
 162 #define I_HINT_STRUCT 1
 163
 164 #define I_HINT_CODE(H) ((H)->code)
 165
 166 #define I_HINT_FREE(H) {   \
 167  indirect_hint_t *h = (H); \
 168  SvREFCNT_dec(h->code);    \
 169  PerlMemShared_free(h);    \
 170 }
 171
 172 #else  /*  I_WORKAROUND_REQUIRE_PROPAGATION */
 173
 174 typedef SV indirect_hint_t;
 175
 176 #define I_HINT_STRUCT 0
 177
 178 #define I_HINT_CODE(H) (H)
 179
 180 #define I_HINT_FREE(H) SvREFCNT_dec(H);
 181
 182 #endif /* !I_WORKAROUND_REQUIRE_PROPAGATION */
 183
 184 #if I_THREADSAFE
 185
 186 #define PTABLE_NAME        ptable_hints
 187 #define PTABLE_VAL_FREE(V) I_HINT_FREE(V)
 188
 189 #define pPTBL  pTHX
 190 #define pPTBL_ pTHX_
 191 #define aPTBL  aTHX
 192 #define aPTBL_ aTHX_
 193
 194 #include "ptable.h"
 195
 196 #define ptable_hints_store(T, K, V) ptable_hints_store(aTHX_ (T), (K), (V))
 197 #define ptable_hints_free(T)        ptable_hints_free(aTHX_ (T))
 198
 199 #endif /* I_THREADSAFE */
 200
 201 /* Define the op->str ptable here because we need to be able to clean it during
 202  * thread cleanup. */
 203
 204 typedef struct {
 205  const char *pos;
 206  char       *buf;
 207  STRLEN      len, size;
 208  line_t      line;
 209 } indirect_op_info_t;
 210
 211 #define PTABLE_NAME        ptable
 212 #define PTABLE_VAL_FREE(V) if (V) { Safefree(((indirect_op_info_t *) (V))->buf); Safefree(V); }
 213
 214 #define pPTBL  pTHX
 215 #define pPTBL_ pTHX_
 216 #define aPTBL  aTHX
 217 #define aPTBL_ aTHX_
 218
 219 #include "ptable.h"
 220
 221 #define ptable_store(T, K, V) ptable_store(aTHX_ (T), (K), (V))
 222 #define ptable_clear(T)       ptable_clear(aTHX_ (T))
 223 #define ptable_free(T)        ptable_free(aTHX_ (T))
 224
 225 #define MY_CXT_KEY __PACKAGE__ "::_guts" XS_VERSION
 226
 227 typedef struct {
 228 #if I_THREADSAFE
 229  ptable     *tbl; /* It really is a ptable_hints */
 230  tTHX        owner;
 231 #endif
 232  ptable     *map;
 233  const char *linestr;
 234 } my_cxt_t;
 235
 236 START_MY_CXT
 237
 238 #if I_THREADSAFE
 239
 240 STATIC SV *indirect_clone(pTHX_ SV *sv, tTHX owner) {
 241 #define indirect_clone(S, O) indirect_clone(aTHX_ (S), (O))
 242  CLONE_PARAMS  param;
 243  AV           *stashes = NULL;
 244  SV           *dupsv;
 245
 246  if (SvTYPE(sv) == SVt_PVHV && HvNAME_get(sv))
 247   stashes = newAV();
 248
 249  param.stashes    = stashes;
 250  param.flags      = 0;
 251  param.proto_perl = owner;
 252
 253  dupsv = sv_dup(sv, &param);
 254
 255  if (stashes) {
 256   av_undef(stashes);
 257   SvREFCNT_dec(stashes);
 258  }
 259
 260  return SvREFCNT_inc(dupsv);
 261 }
 262
 263 STATIC void indirect_ptable_clone(pTHX_ ptable_ent *ent, void *ud_) {
 264  my_cxt_t        *ud = ud_;
 265  indirect_hint_t *h1 = ent->val;
 266  indirect_hint_t *h2;
 267
 268  if (ud->owner == aTHX)
 269   return;
 270
 271 #if I_HINT_STRUCT
 272
 273  h2       = PerlMemShared_malloc(sizeof *h2);
 274  h2->code = indirect_clone(h1->code, ud->owner);
 275  SvREFCNT_inc(h2->code);
 276 #if I_WORKAROUND_REQUIRE_PROPAGATION
 277  h2->require_tag = PTR2IV(indirect_clone(INT2PTR(SV *, h1->require_tag),
 278                                          ud->owner));
 279 #endif
 280
 281 #else  /*  I_HINT_STRUCT */
 282
 283  h2 = indirect_clone(h1, ud->owner);
 284  SvREFCNT_inc(h2);
 285
 286 #endif /* !I_HINT_STRUCT */
 287
 288  ptable_hints_store(ud->tbl, ent->key, h2);
 289 }
 290
 291 STATIC void indirect_thread_cleanup(pTHX_ void *);
 292
 293 STATIC void indirect_thread_cleanup(pTHX_ void *ud) {
 294  int *level = ud;
 295
 296  if (*level) {
 297   *level = 0;
 298   LEAVE;
 299   SAVEDESTRUCTOR_X(indirect_thread_cleanup, level);
 300   ENTER;
 301  } else {
 302   dMY_CXT;
 303   PerlMemShared_free(level);
 304   ptable_free(MY_CXT.map);
 305   ptable_hints_free(MY_CXT.tbl);
 306  }
 307 }
 308
 309 #endif /* I_THREADSAFE */
 310
 311 #if I_WORKAROUND_REQUIRE_PROPAGATION
 312 STATIC IV indirect_require_tag(pTHX) {
 313 #define indirect_require_tag() indirect_require_tag(aTHX)
 314  const CV *cv, *outside;
 315
 316  cv = PL_compcv;
 317
 318  if (!cv) {
 319   /* If for some reason the pragma is operational at run-time, try to discover
 320    * the current cv in use. */
 321   const PERL_SI *si;
 322
 323   for (si = PL_curstackinfo; si; si = si->si_prev) {
 324    I32 cxix;
 325
 326    for (cxix = si->si_cxix; cxix >= 0; --cxix) {
 327     const PERL_CONTEXT *cx = si->si_cxstack + cxix;
 328
 329     switch (CxTYPE(cx)) {
 330      case CXt_SUB:
 331      case CXt_FORMAT:
 332       /* The propagation workaround is only needed up to 5.10.0 and at that
 333        * time format and sub contexts were still identical. And even later the
 334        * cv members offsets should have been kept the same. */
 335       cv = cx->blk_sub.cv;
 336       goto get_enclosing_cv;
 337      case CXt_EVAL:
 338       cv = cx->blk_eval.cv;
 339       goto get_enclosing_cv;
 340      default:
 341       break;
 342     }
 343    }
 344   }
 345
 346   cv = PL_main_cv;
 347  }
 348
 349 get_enclosing_cv:
 350  for (outside = CvOUTSIDE(cv); outside; outside = CvOUTSIDE(cv))
 351   cv = outside;
 352
 353  return PTR2IV(cv);
 354 }
 355 #endif /* I_WORKAROUND_REQUIRE_PROPAGATION */
 356
 357 STATIC SV *indirect_tag(pTHX_ SV *value) {
 358 #define indirect_tag(V) indirect_tag(aTHX_ (V))
 359  indirect_hint_t *h;
 360  SV *code = NULL;
 361  dMY_CXT;
 362
 363  if (SvROK(value)) {
 364   value = SvRV(value);
 365   if (SvTYPE(value) >= SVt_PVCV) {
 366    code = value;
 367    SvREFCNT_inc_simple_NN(code);
 368   }
 369  }
 370
 371 #if I_HINT_STRUCT
 372  h = PerlMemShared_malloc(sizeof *h);
 373  h->code        = code;
 374 # if I_WORKAROUND_REQUIRE_PROPAGATION
 375  h->require_tag = indirect_require_tag();
 376 # endif /* I_WORKAROUND_REQUIRE_PROPAGATION */
 377 #else  /*  I_HINT_STRUCT */
 378  h = code;
 379 #endif /* !I_HINT_STRUCT */
 380
 381 #if I_THREADSAFE
 382  /* We only need for the key to be an unique tag for looking up the value later.
 383   * Allocated memory provides convenient unique identifiers, so that's why we
 384   * use the hint as the key itself. */
 385  ptable_hints_store(MY_CXT.tbl, h, h);
 386 #endif /* I_THREADSAFE */
 387
 388  return newSViv(PTR2IV(h));
 389 }
 390
 391 STATIC SV *indirect_detag(pTHX_ const SV *hint) {
 392 #define indirect_detag(H) indirect_detag(aTHX_ (H))
 393  indirect_hint_t *h;
 394  dMY_CXT;
 395
 396  if (!(hint && SvIOK(hint)))
 397   return NULL;
 398
 399  h = INT2PTR(indirect_hint_t *, SvIVX(hint));
 400 #if I_THREADSAFE
 401  h = ptable_fetch(MY_CXT.tbl, h);
 402 #endif /* I_THREADSAFE */
 403
 404 #if I_WORKAROUND_REQUIRE_PROPAGATION
 405  if (indirect_require_tag() != h->require_tag)
 406   return NULL;
 407 #endif /* I_WORKAROUND_REQUIRE_PROPAGATION */
 408
 409  return I_HINT_CODE(h);
 410 }
 411
 412 STATIC U32 indirect_hash = 0;
 413
 414 STATIC SV *indirect_hint(pTHX) {
 415 #define indirect_hint() indirect_hint(aTHX)
 416  SV *hint;
 417
 418  if (IN_PERL_RUNTIME)
 419   return NULL;
 420
 421 #if I_HAS_PERL(5, 9, 5)
 422  hint = Perl_refcounted_he_fetch(aTHX_ PL_curcop->cop_hints_hash,
 423                                        NULL,
 424                                        __PACKAGE__, __PACKAGE_LEN__,
 425                                        0,
 426                                        indirect_hash);
 427 #else
 428  {
 429   SV **val = hv_fetch(GvHV(PL_hintgv), __PACKAGE__, __PACKAGE_LEN__,
 430                                                                  indirect_hash);
 431   if (!val)
 432    return 0;
 433   hint = *val;
 434  }
 435 #endif
 436  return indirect_detag(hint);
 437 }
 438
 439 /* ... op -> source position ............................................... */
 440
 441 STATIC void indirect_map_store(pTHX_ const OP *o, const char *src, SV *sv, line_t line) {
 442 #define indirect_map_store(O, S, N, L) indirect_map_store(aTHX_ (O), (S), (N), (L))
 443  indirect_op_info_t *oi;
 444  const char *s;
 445  STRLEN len;
 446  dMY_CXT;
 447
 448  /* When lex_inwhat is set, we're in a quotelike environment (qq, qr, but not q)
 449   * In this case the linestr has temporarly changed, but the old buffer should
 450   * still be alive somewhere. */
 451
 452  if (!PL_lex_inwhat) {
 453   const char *pl_linestr = SvPVX_const(PL_linestr);
 454   if (MY_CXT.linestr != pl_linestr) {
 455    ptable_clear(MY_CXT.map);
 456    MY_CXT.linestr = pl_linestr;
 457   }
 458  }
 459
 460  if (!(oi = ptable_fetch(MY_CXT.map, o))) {
 461   Newx(oi, 1, indirect_op_info_t);
 462   ptable_store(MY_CXT.map, o, oi);
 463   oi->buf  = NULL;
 464   oi->size = 0;
 465  }
 466
 467  if (sv) {
 468   s = SvPV_const(sv, len);
 469  } else {
 470   s   = "{";
 471   len = 1;
 472  }
 473
 474  if (len > oi->size) {
 475   Safefree(oi->buf);
 476   Newx(oi->buf, len, char);
 477   oi->size = len;
 478  }
 479  Copy(s, oi->buf, len, char);
 480
 481  oi->len  = len;
 482  oi->pos  = src;
 483  oi->line = line;
 484 }
 485
 486 STATIC const indirect_op_info_t *indirect_map_fetch(pTHX_ const OP *o) {
 487 #define indirect_map_fetch(O) indirect_map_fetch(aTHX_ (O))
 488  const indirect_op_info_t *val;
 489  dMY_CXT;
 490
 491  if (MY_CXT.linestr != SvPVX_const(PL_linestr))
 492   return NULL;
 493
 494  return ptable_fetch(MY_CXT.map, o);
 495 }
 496
 497 STATIC void indirect_map_delete(pTHX_ const OP *o) {
 498 #define indirect_map_delete(O) indirect_map_delete(aTHX_ (O))
 499  dMY_CXT;
 500
 501  ptable_store(MY_CXT.map, o, NULL);
 502 }
 503
 504 /* --- Check functions ----------------------------------------------------- */
 505
 506 STATIC const char *indirect_find(pTHX_ SV *sv, const char *s) {
 507 #define indirect_find(N, S) indirect_find(aTHX_ (N), (S))
 508  STRLEN len;
 509  const char *p = NULL, *r = SvPV_const(sv, len);
 510
 511  if (len >= 1 && *r == '$') {
 512   ++r;
 513   --len;
 514   s = strchr(s, '$');
 515   if (!s)
 516    return NULL;
 517  }
 518
 519  p = strstr(s, r);
 520  while (p) {
 521   p += len;
 522   if (!isALNUM(*p))
 523    break;
 524   p = strstr(p + 1, r);
 525  }
 526
 527  return p;
 528 }
 529
 530 /* ... ck_const ............................................................ */
 531
 532 STATIC OP *(*indirect_old_ck_const)(pTHX_ OP *) = 0;
 533
 534 STATIC OP *indirect_ck_const(pTHX_ OP *o) {
 535  o = CALL_FPTR(indirect_old_ck_const)(aTHX_ o);
 536
 537  if (indirect_hint()) {
 538   SV *sv = cSVOPo_sv;
 539   if (SvPOK(sv) && (SvTYPE(sv) >= SVt_PV)) {
 540    const char *s = indirect_find(sv, PL_oldbufptr);
 541    indirect_map_store(o, s, sv, CopLINE(&PL_compiling));
 542    return o;
 543   }
 544  }
 545
 546  indirect_map_delete(o);
 547  return o;
 548 }
 549
 550 /* ... ck_rv2sv ............................................................ */
 551
 552 STATIC OP *(*indirect_old_ck_rv2sv)(pTHX_ OP *) = 0;
 553
 554 STATIC OP *indirect_ck_rv2sv(pTHX_ OP *o) {
 555  if (indirect_hint()) {
 556   OP *op = cUNOPo->op_first;
 557   SV *sv;
 558   const char *name = NULL, *s;
 559   STRLEN len;
 560   OPCODE type = (OPCODE) op->op_type;
 561
 562   switch (type) {
 563    case OP_GV:
 564    case OP_GVSV: {
 565     GV *gv = cGVOPx_gv(op);
 566     name = GvNAME(gv);
 567     len  = GvNAMELEN(gv);
 568     break;
 569    }
 570    default:
 571     if ((PL_opargs[type] & OA_CLASS_MASK) == OA_SVOP) {
 572      SV *nsv = cSVOPx_sv(op);
 573      if (SvPOK(nsv) && (SvTYPE(nsv) >= SVt_PV))
 574       name = SvPV_const(nsv, len);
 575     }
 576   }
 577   if (!name)
 578    goto done;
 579
 580   sv = sv_2mortal(newSVpvn("$", 1));
 581   sv_catpvn_nomg(sv, name, len);
 582   s = indirect_find(sv, PL_oldbufptr);
 583   if (!s) { /* If it failed, retry without the current stash */
 584    const char *stash = HvNAME_get(PL_curstash);
 585    STRLEN stashlen = HvNAMELEN_get(PL_curstash);
 586
 587    if ((len < stashlen + 2) || strnNE(name, stash, stashlen)
 588        || name[stashlen] != ':' || name[stashlen+1] != ':') {
 589     /* Failed again ? Try to remove main */
 590     stash = "main";
 591     stashlen = 4;
 592     if ((len < stashlen + 2) || strnNE(name, stash, stashlen)
 593         || name[stashlen] != ':' || name[stashlen+1] != ':')
 594      goto done;
 595    }
 596
 597    sv_setpvn(sv, "$", 1);
 598    stashlen += 2;
 599    sv_catpvn_nomg(sv, name + stashlen, len - stashlen);
 600    s = indirect_find(sv, PL_oldbufptr);
 601    if (!s)
 602     goto done;
 603   }
 604
 605   o = CALL_FPTR(indirect_old_ck_rv2sv)(aTHX_ o);
 606   indirect_map_store(o, s, sv, CopLINE(&PL_compiling));
 607   return o;
 608  }
 609
 610 done:
 611  o = CALL_FPTR(indirect_old_ck_rv2sv)(aTHX_ o);
 612
 613  indirect_map_delete(o);
 614  return o;
 615 }
 616
 617 /* ... ck_padany ........................................................... */
 618
 619 STATIC OP *(*indirect_old_ck_padany)(pTHX_ OP *) = 0;
 620
 621 STATIC OP *indirect_ck_padany(pTHX_ OP *o) {
 622  o = CALL_FPTR(indirect_old_ck_padany)(aTHX_ o);
 623
 624  if (indirect_hint()) {
 625   SV *sv;
 626   const char *s = PL_oldbufptr, *t = PL_bufptr - 1;
 627
 628   while (s < t && isSPACE(*s)) ++s;
 629   if (*s == '$' && ++s <= t) {
 630    while (s < t && isSPACE(*s)) ++s;
 631    while (s < t && isSPACE(*t)) --t;
 632    sv = sv_2mortal(newSVpvn("$", 1));
 633    sv_catpvn_nomg(sv, s, t - s + 1);
 634    indirect_map_store(o, s, sv, CopLINE(&PL_compiling));
 635    return o;
 636   }
 637  }
 638
 639  indirect_map_delete(o);
 640  return o;
 641 }
 642
 643 /* ... ck_scope ............................................................ */
 644
 645 STATIC OP *(*indirect_old_ck_scope)  (pTHX_ OP *) = 0;
 646 STATIC OP *(*indirect_old_ck_lineseq)(pTHX_ OP *) = 0;
 647
 648 STATIC OP *indirect_ck_scope(pTHX_ OP *o) {
 649  OP *(*old_ck)(pTHX_ OP *) = 0;
 650
 651  switch (o->op_type) {
 652   case OP_SCOPE:   old_ck = indirect_old_ck_scope;   break;
 653   case OP_LINESEQ: old_ck = indirect_old_ck_lineseq; break;
 654  }
 655  o = CALL_FPTR(old_ck)(aTHX_ o);
 656
 657  if (indirect_hint()) {
 658   indirect_map_store(o, PL_oldbufptr, NULL, CopLINE(&PL_compiling));
 659   return o;
 660  }
 661
 662  indirect_map_delete(o);
 663  return o;
 664 }
 665
 666 /* We don't need to clean the map entries for leave ops because they can only
 667  * be created by mutating from a lineseq. */
 668
 669 /* ... ck_method ........................................................... */
 670
 671 STATIC OP *(*indirect_old_ck_method)(pTHX_ OP *) = 0;
 672
 673 STATIC OP *indirect_ck_method(pTHX_ OP *o) {
 674  if (indirect_hint()) {
 675   OP *op = cUNOPo->op_first;
 676   const indirect_op_info_t *oi = indirect_map_fetch(op);
 677   const char *s = NULL;
 678   line_t line;
 679   SV *sv;
 680
 681   if (oi && (s = oi->pos)) {
 682    sv   = sv_2mortal(newSVpvn(oi->buf, oi->len));
 683    line = oi->line; /* Keep the old line so that we really point to the first */
 684   } else {
 685    sv = cSVOPx_sv(op);
 686    if (!SvPOK(sv) || (SvTYPE(sv) < SVt_PV))
 687     goto done;
 688    sv   = sv_mortalcopy(sv);
 689    s    = indirect_find(sv, PL_oldbufptr);
 690    line = CopLINE(&PL_compiling);
 691   }
 692
 693   o = CALL_FPTR(indirect_old_ck_method)(aTHX_ o);
 694   /* o may now be a method_named */
 695
 696   indirect_map_store(o, s, sv, line);
 697   return o;
 698  }
 699
 700 done:
 701  o = CALL_FPTR(indirect_old_ck_method)(aTHX_ o);
 702
 703  indirect_map_delete(o);
 704  return o;
 705 }
 706
 707 /* ... ck_entersub ......................................................... */
 708
 709 STATIC int indirect_is_indirect(const indirect_op_info_t *moi, const indirect_op_info_t *ooi) {
 710  if (moi->pos > ooi->pos)
 711   return 0;
 712
 713  if (moi->pos == ooi->pos)
 714   return moi->len == ooi->len && !memcmp(moi->buf, ooi->buf, moi->len);
 715
 716  return 1;
 717 }
 718
 719 STATIC OP *(*indirect_old_ck_entersub)(pTHX_ OP *) = 0;
 720
 721 STATIC OP *indirect_ck_entersub(pTHX_ OP *o) {
 722  SV *code = indirect_hint();
 723
 724  o = CALL_FPTR(indirect_old_ck_entersub)(aTHX_ o);
 725
 726  if (code) {
 727   const indirect_op_info_t *moi, *ooi;
 728   OP     *mop, *oop;
 729   LISTOP *lop;
 730
 731   oop = o;
 732   do {
 733    lop = (LISTOP *) oop;
 734    if (!(lop->op_flags & OPf_KIDS))
 735     goto done;
 736    oop = lop->op_first;
 737   } while (oop->op_type != OP_PUSHMARK);
 738   oop = oop->op_sibling;
 739   mop = lop->op_last;
 740
 741   if (!oop)
 742    goto done;
 743
 744   switch (oop->op_type) {
 745    case OP_CONST:
 746    case OP_RV2SV:
 747    case OP_PADSV:
 748    case OP_SCOPE:
 749    case OP_LEAVE:
 750     break;
 751    default:
 752     goto done;
 753   }
 754
 755   if (mop->op_type == OP_METHOD)
 756    mop = cUNOPx(mop)->op_first;
 757   else if (mop->op_type != OP_METHOD_NAMED)
 758    goto done;
 759
 760   moi = indirect_map_fetch(mop);
 761   if (!(moi && moi->pos))
 762    goto done;
 763
 764   ooi = indirect_map_fetch(oop);
 765   if (!(ooi && ooi->pos))
 766    goto done;
 767
 768   if (indirect_is_indirect(moi, ooi)) {
 769    SV *file;
 770    dSP;
 771
 772    ENTER;
 773    SAVETMPS;
 774
 775 #ifdef USE_ITHREADS
 776    file = sv_2mortal(newSVpv(CopFILE(&PL_compiling), 0));
 777 #else
 778    file = sv_mortalcopy(CopFILESV(&PL_compiling));
 779 #endif
 780
 781    PUSHMARK(SP);
 782    EXTEND(SP, 4);
 783    mPUSHp(ooi->buf, ooi->len);
 784    mPUSHp(moi->buf, moi->len);
 785    PUSHs(file);
 786    mPUSHu(moi->line);
 787    PUTBACK;
 788
 789    call_sv(code, G_VOID);
 790
 791    PUTBACK;
 792
 793    FREETMPS;
 794    LEAVE;
 795   }
 796  }
 797
 798 done:
 799  return o;
 800 }
 801
 802 STATIC U32 indirect_initialized = 0;
 803
 804 STATIC void indirect_teardown(pTHX_ void *root) {
 805  dMY_CXT;
 806
 807  if (!indirect_initialized)
 808   return;
 809
 810 #if I_MULTIPLICITY
 811  if (aTHX != root)
 812   return;
 813 #endif
 814
 815  ptable_free(MY_CXT.map);
 816 #if I_THREADSAFE
 817  ptable_hints_free(MY_CXT.tbl);
 818 #endif
 819
 820  PL_check[OP_CONST]       = MEMBER_TO_FPTR(indirect_old_ck_const);
 821  indirect_old_ck_const    = 0;
 822  PL_check[OP_RV2SV]       = MEMBER_TO_FPTR(indirect_old_ck_rv2sv);
 823  indirect_old_ck_rv2sv    = 0;
 824  PL_check[OP_PADANY]      = MEMBER_TO_FPTR(indirect_old_ck_padany);
 825  indirect_old_ck_padany   = 0;
 826  PL_check[OP_SCOPE]       = MEMBER_TO_FPTR(indirect_old_ck_scope);
 827  indirect_old_ck_scope    = 0;
 828  PL_check[OP_LINESEQ]     = MEMBER_TO_FPTR(indirect_old_ck_lineseq);
 829  indirect_old_ck_lineseq  = 0;
 830
 831  PL_check[OP_METHOD]      = MEMBER_TO_FPTR(indirect_old_ck_method);
 832  indirect_old_ck_method   = 0;
 833  PL_check[OP_ENTERSUB]    = MEMBER_TO_FPTR(indirect_old_ck_entersub);
 834  indirect_old_ck_entersub = 0;
 835
 836  indirect_initialized = 0;
 837 }
 838
 839 STATIC void indirect_setup(pTHX) {
 840 #define indirect_setup() indirect_setup(aTHX)
 841  if (indirect_initialized)
 842   return;
 843
 844  MY_CXT_INIT;
 845 #if I_THREADSAFE
 846  MY_CXT.tbl     = ptable_new();
 847  MY_CXT.owner   = aTHX;
 848 #endif
 849  MY_CXT.map     = ptable_new();
 850  MY_CXT.linestr = NULL;
 851
 852  indirect_old_ck_const    = PL_check[OP_CONST];
 853  PL_check[OP_CONST]       = MEMBER_TO_FPTR(indirect_ck_const);
 854  indirect_old_ck_rv2sv    = PL_check[OP_RV2SV];
 855  PL_check[OP_RV2SV]       = MEMBER_TO_FPTR(indirect_ck_rv2sv);
 856  indirect_old_ck_padany   = PL_check[OP_PADANY];
 857  PL_check[OP_PADANY]      = MEMBER_TO_FPTR(indirect_ck_padany);
 858  indirect_old_ck_scope    = PL_check[OP_SCOPE];
 859  PL_check[OP_SCOPE]       = MEMBER_TO_FPTR(indirect_ck_scope);
 860  indirect_old_ck_lineseq  = PL_check[OP_LINESEQ];
 861  PL_check[OP_LINESEQ]     = MEMBER_TO_FPTR(indirect_ck_scope);
 862
 863  indirect_old_ck_method   = PL_check[OP_METHOD];
 864  PL_check[OP_METHOD]      = MEMBER_TO_FPTR(indirect_ck_method);
 865  indirect_old_ck_entersub = PL_check[OP_ENTERSUB];
 866  PL_check[OP_ENTERSUB]    = MEMBER_TO_FPTR(indirect_ck_entersub);
 867
 868 #if I_MULTIPLICITY
 869  call_atexit(indirect_teardown, aTHX);
 870 #else
 871  call_atexit(indirect_teardown, NULL);
 872 #endif
 873
 874  indirect_initialized = 1;
 875 }
 876
 877 STATIC U32 indirect_booted = 0;
 878
 879 /* --- XS ------------------------------------------------------------------ */
 880
 881 MODULE = indirect      PACKAGE = indirect
 882
 883 PROTOTYPES: ENABLE
 884
 885 BOOT:
 886 {
 887  if (!indirect_booted++) {
 888   HV *stash;
 889
 890   PERL_HASH(indirect_hash, __PACKAGE__, __PACKAGE_LEN__);
 891
 892   stash = gv_stashpvn(__PACKAGE__, __PACKAGE_LEN__, 1);
 893   newCONSTSUB(stash, "I_THREADSAFE", newSVuv(I_THREADSAFE));
 894   newCONSTSUB(stash, "I_FORKSAFE",   newSVuv(I_FORKSAFE));
 895  }
 896
 897  indirect_setup();
 898 }
 899
 900 #if I_THREADSAFE
 901
 902 void
 903 CLONE(...)
 904 PROTOTYPE: DISABLE
 905 PREINIT:
 906  ptable *t;
 907  int    *level;
 908 CODE:
 909  {
 910   my_cxt_t ud;
 911   dMY_CXT;
 912   ud.tbl   = t = ptable_new();
 913   ud.owner = MY_CXT.owner;
 914   ptable_walk(MY_CXT.tbl, indirect_ptable_clone, &ud);
 915  }
 916  {
 917   MY_CXT_CLONE;
 918   MY_CXT.map     = ptable_new();
 919   MY_CXT.linestr = NULL;
 920   MY_CXT.tbl     = t;
 921   MY_CXT.owner   = aTHX;
 922  }
 923  {
 924   level = PerlMemShared_malloc(sizeof *level);
 925   *level = 1;
 926   LEAVEn("sub");
 927   SAVEDESTRUCTOR_X(indirect_thread_cleanup, level);
 928   ENTERn("sub");
 929  }
 930
 931 #endif
 932
 933 SV *
 934 _tag(SV *value)
 935 PROTOTYPE: $
 936 CODE:
 937  RETVAL = indirect_tag(value);
 938 OUTPUT:
 939  RETVAL