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_void_NN
  39 # ifdef SvREFCNT_inc_simple_NN
  40 #  define SvREFCNT_inc_simple_void_NN SvREFCNT_inc_simple_NN
  41 # else
  42 #  define SvREFCNT_inc_simple_void_NN SvREFCNT_inc
  43 # endif
  44 #endif
  45
  46 #ifndef sv_catpvn_nomg
  47 # define sv_catpvn_nomg sv_catpvn
  48 #endif
  49
  50 #ifndef mPUSHp
  51 # define mPUSHp(P, L) PUSHs(sv_2mortal(newSVpvn((P), (L))))
  52 #endif
  53
  54 #ifndef mPUSHu
  55 # define mPUSHu(U) PUSHs(sv_2mortal(newSVuv(U)))
  56 #endif
  57
  58 #ifndef HvNAME_get
  59 # define HvNAME_get(H) HvNAME(H)
  60 #endif
  61
  62 #ifndef HvNAMELEN_get
  63 # define HvNAMELEN_get(H) strlen(HvNAME_get(H))
  64 #endif
  65
  66 #define I_HAS_PERL(R, V, S) (PERL_REVISION > (R) || (PERL_REVISION == (R) && (PERL_VERSION > (V) || (PERL_VERSION == (V) && (PERL_SUBVERSION >= (S))))))
  67
  68 #if I_HAS_PERL(5, 10, 0) || defined(PL_parser)
  69 # ifndef PL_linestr
  70 #  define PL_linestr PL_parser->linestr
  71 # endif
  72 # ifndef PL_bufptr
  73 #  define PL_bufptr PL_parser->bufptr
  74 # endif
  75 # ifndef PL_oldbufptr
  76 #  define PL_oldbufptr PL_parser->oldbufptr
  77 # endif
  78 # ifndef PL_lex_inwhat
  79 #  define PL_lex_inwhat PL_parser->lex_inwhat
  80 # endif
  81 #else
  82 # ifndef PL_linestr
  83 #  define PL_linestr PL_Ilinestr
  84 # endif
  85 # ifndef PL_bufptr
  86 #  define PL_bufptr PL_Ibufptr
  87 # endif
  88 # ifndef PL_oldbufptr
  89 #  define PL_oldbufptr PL_Ioldbufptr
  90 # endif
  91 # ifndef PL_lex_inwhat
  92 #  define PL_lex_inwhat PL_Ilex_inwhat
  93 # endif
  94 #endif
  95
  96 #ifndef I_WORKAROUND_REQUIRE_PROPAGATION
  97 # define I_WORKAROUND_REQUIRE_PROPAGATION !I_HAS_PERL(5, 10, 1)
  98 #endif
  99
 100 /* ... Thread safety and multiplicity ...................................... */
 101
 102 /* Safe unless stated otherwise in Makefile.PL */
 103 #ifndef I_FORKSAFE
 104 # define I_FORKSAFE 1
 105 #endif
 106
 107 #ifndef I_MULTIPLICITY
 108 # if defined(MULTIPLICITY) || defined(PERL_IMPLICIT_CONTEXT)
 109 #  define I_MULTIPLICITY 1
 110 # else
 111 #  define I_MULTIPLICITY 0
 112 # endif
 113 #endif
 114 #if I_MULTIPLICITY && !defined(tTHX)
 115 # define tTHX PerlInterpreter*
 116 #endif
 117
 118 #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))
 119 # define I_THREADSAFE 1
 120 # ifndef MY_CXT_CLONE
 121 #  define MY_CXT_CLONE \
 122     dMY_CXT_SV;                                                      \
 123     my_cxt_t *my_cxtp = (my_cxt_t*)SvPVX(newSV(sizeof(my_cxt_t)-1)); \
 124     Copy(INT2PTR(my_cxt_t*, SvUV(my_cxt_sv)), my_cxtp, 1, my_cxt_t); \
 125     sv_setuv(my_cxt_sv, PTR2UV(my_cxtp))
 126 # endif
 127 #else
 128 # define I_THREADSAFE 0
 129 # undef  dMY_CXT
 130 # define dMY_CXT      dNOOP
 131 # undef  MY_CXT
 132 # define MY_CXT       indirect_globaldata
 133 # undef  START_MY_CXT
 134 # define START_MY_CXT STATIC my_cxt_t MY_CXT;
 135 # undef  MY_CXT_INIT
 136 # define MY_CXT_INIT  NOOP
 137 # undef  MY_CXT_CLONE
 138 # define MY_CXT_CLONE NOOP
 139 #endif
 140
 141 #if defined(OP_CHECK_MUTEX_LOCK) && defined(OP_CHECK_MUTEX_UNLOCK)
 142 # define I_CHECK_MUTEX_LOCK   OP_CHECK_MUTEX_LOCK
 143 # define I_CHECK_MUTEX_UNLOCK OP_CHECK_MUTEX_UNLOCK
 144 #else
 145 # define I_CHECK_MUTEX_LOCK   OP_REFCNT_LOCK
 146 # define I_CHECK_MUTEX_UNLOCK OP_REFCNT_UNLOCK
 147 #endif
 148
 149 typedef OP *(*indirect_ck_t)(pTHX_ OP *);
 150
 151 #ifdef wrap_op_checker
 152
 153 # define indirect_ck_replace(T, NC, OCP) wrap_op_checker((T), (NC), (OCP))
 154
 155 #else
 156
 157 STATIC void indirect_ck_replace(pTHX_ OPCODE type, indirect_ck_t new_ck, indirect_ck_t *old_ck_p) {
 158 #define indirect_ck_replace(T, NC, OCP) indirect_ck_replace(aTHX_ (T), (NC), (OCP))
 159  I_CHECK_MUTEX_LOCK;
 160  if (!*old_ck_p) {
 161   *old_ck_p      = PL_check[type];
 162   PL_check[type] = new_ck;
 163  }
 164  I_CHECK_MUTEX_UNLOCK;
 165 }
 166
 167 #endif
 168
 169 STATIC void indirect_ck_restore(pTHX_ OPCODE type, indirect_ck_t *old_ck_p) {
 170 #define indirect_ck_restore(T, OCP) indirect_ck_restore(aTHX_ (T), (OCP))
 171  I_CHECK_MUTEX_LOCK;
 172  if (*old_ck_p) {
 173   PL_check[type] = *old_ck_p;
 174   *old_ck_p      = 0;
 175  }
 176  I_CHECK_MUTEX_UNLOCK;
 177 }
 178
 179 /* --- Helpers ------------------------------------------------------------- */
 180
 181 /* ... Thread-safe hints ................................................... */
 182
 183 #if I_WORKAROUND_REQUIRE_PROPAGATION
 184
 185 typedef struct {
 186  SV *code;
 187  IV  require_tag;
 188 } indirect_hint_t;
 189
 190 #define I_HINT_STRUCT 1
 191
 192 #define I_HINT_CODE(H) ((H)->code)
 193
 194 #define I_HINT_FREE(H) {   \
 195  indirect_hint_t *h = (H); \
 196  SvREFCNT_dec(h->code);    \
 197  PerlMemShared_free(h);    \
 198 }
 199
 200 #else  /*  I_WORKAROUND_REQUIRE_PROPAGATION */
 201
 202 typedef SV indirect_hint_t;
 203
 204 #define I_HINT_STRUCT 0
 205
 206 #define I_HINT_CODE(H) (H)
 207
 208 #define I_HINT_FREE(H) SvREFCNT_dec(H);
 209
 210 #endif /* !I_WORKAROUND_REQUIRE_PROPAGATION */
 211
 212 #if I_THREADSAFE
 213
 214 #define PTABLE_NAME        ptable_hints
 215 #define PTABLE_VAL_FREE(V) I_HINT_FREE(V)
 216
 217 #define pPTBL  pTHX
 218 #define pPTBL_ pTHX_
 219 #define aPTBL  aTHX
 220 #define aPTBL_ aTHX_
 221
 222 #include "ptable.h"
 223
 224 #define ptable_hints_store(T, K, V) ptable_hints_store(aTHX_ (T), (K), (V))
 225 #define ptable_hints_free(T)        ptable_hints_free(aTHX_ (T))
 226
 227 #endif /* I_THREADSAFE */
 228
 229 /* Define the op->str ptable here because we need to be able to clean it during
 230  * thread cleanup. */
 231
 232 typedef struct {
 233  char   *buf;
 234  STRLEN  pos;
 235  STRLEN  size;
 236  STRLEN  len;
 237  line_t  line;
 238 } indirect_op_info_t;
 239
 240 #define PTABLE_NAME        ptable
 241 #define PTABLE_VAL_FREE(V) if (V) { Safefree(((indirect_op_info_t *) (V))->buf); Safefree(V); }
 242
 243 #define pPTBL  pTHX
 244 #define pPTBL_ pTHX_
 245 #define aPTBL  aTHX
 246 #define aPTBL_ aTHX_
 247
 248 #include "ptable.h"
 249
 250 #define ptable_store(T, K, V) ptable_store(aTHX_ (T), (K), (V))
 251 #define ptable_delete(T, K)   ptable_delete(aTHX_ (T), (K))
 252 #define ptable_clear(T)       ptable_clear(aTHX_ (T))
 253 #define ptable_free(T)        ptable_free(aTHX_ (T))
 254
 255 #define MY_CXT_KEY __PACKAGE__ "::_guts" XS_VERSION
 256
 257 typedef struct {
 258 #if I_THREADSAFE
 259  ptable *tbl; /* It really is a ptable_hints */
 260  tTHX    owner;
 261 #endif
 262  ptable *map;
 263  SV     *global_code;
 264 } my_cxt_t;
 265
 266 START_MY_CXT
 267
 268 #if I_THREADSAFE
 269
 270 STATIC SV *indirect_clone(pTHX_ SV *sv, tTHX owner) {
 271 #define indirect_clone(S, O) indirect_clone(aTHX_ (S), (O))
 272  CLONE_PARAMS  param;
 273  AV           *stashes = NULL;
 274  SV           *dupsv;
 275
 276  if (!sv)
 277   return NULL;
 278
 279  if (SvTYPE(sv) == SVt_PVHV && HvNAME_get(sv))
 280   stashes = newAV();
 281
 282  param.stashes    = stashes;
 283  param.flags      = 0;
 284  param.proto_perl = owner;
 285
 286  dupsv = sv_dup(sv, &param);
 287
 288  if (stashes) {
 289   av_undef(stashes);
 290   SvREFCNT_dec(stashes);
 291  }
 292
 293  return SvREFCNT_inc(dupsv);
 294 }
 295
 296 STATIC void indirect_ptable_clone(pTHX_ ptable_ent *ent, void *ud_) {
 297  my_cxt_t        *ud = ud_;
 298  indirect_hint_t *h1 = ent->val;
 299  indirect_hint_t *h2;
 300
 301  if (ud->owner == aTHX)
 302   return;
 303
 304 #if I_HINT_STRUCT
 305
 306  h2       = PerlMemShared_malloc(sizeof *h2);
 307  h2->code = indirect_clone(h1->code, ud->owner);
 308 #if I_WORKAROUND_REQUIRE_PROPAGATION
 309  h2->require_tag = PTR2IV(indirect_clone(INT2PTR(SV *, h1->require_tag),
 310                                          ud->owner));
 311 #endif
 312
 313 #else  /*  I_HINT_STRUCT */
 314
 315  h2 = indirect_clone(h1, ud->owner);
 316
 317 #endif /* !I_HINT_STRUCT */
 318
 319  ptable_hints_store(ud->tbl, ent->key, h2);
 320 }
 321
 322 #include "reap.h"
 323
 324 STATIC void indirect_thread_cleanup(pTHX_ void *ud) {
 325  dMY_CXT;
 326
 327  SvREFCNT_dec(MY_CXT.global_code);
 328  ptable_free(MY_CXT.map);
 329  ptable_hints_free(MY_CXT.tbl);
 330 }
 331
 332 #endif /* I_THREADSAFE */
 333
 334 #if I_WORKAROUND_REQUIRE_PROPAGATION
 335 STATIC IV indirect_require_tag(pTHX) {
 336 #define indirect_require_tag() indirect_require_tag(aTHX)
 337  const CV *cv, *outside;
 338
 339  cv = PL_compcv;
 340
 341  if (!cv) {
 342   /* If for some reason the pragma is operational at run-time, try to discover
 343    * the current cv in use. */
 344   const PERL_SI *si;
 345
 346   for (si = PL_curstackinfo; si; si = si->si_prev) {
 347    I32 cxix;
 348
 349    for (cxix = si->si_cxix; cxix >= 0; --cxix) {
 350     const PERL_CONTEXT *cx = si->si_cxstack + cxix;
 351
 352     switch (CxTYPE(cx)) {
 353      case CXt_SUB:
 354      case CXt_FORMAT:
 355       /* The propagation workaround is only needed up to 5.10.0 and at that
 356        * time format and sub contexts were still identical. And even later the
 357        * cv members offsets should have been kept the same. */
 358       cv = cx->blk_sub.cv;
 359       goto get_enclosing_cv;
 360      case CXt_EVAL:
 361       cv = cx->blk_eval.cv;
 362       goto get_enclosing_cv;
 363      default:
 364       break;
 365     }
 366    }
 367   }
 368
 369   cv = PL_main_cv;
 370  }
 371
 372 get_enclosing_cv:
 373  for (outside = CvOUTSIDE(cv); outside; outside = CvOUTSIDE(cv))
 374   cv = outside;
 375
 376  return PTR2IV(cv);
 377 }
 378 #endif /* I_WORKAROUND_REQUIRE_PROPAGATION */
 379
 380 STATIC SV *indirect_tag(pTHX_ SV *value) {
 381 #define indirect_tag(V) indirect_tag(aTHX_ (V))
 382  indirect_hint_t *h;
 383  SV *code = NULL;
 384
 385  if (SvROK(value)) {
 386   value = SvRV(value);
 387   if (SvTYPE(value) >= SVt_PVCV) {
 388    code = value;
 389    SvREFCNT_inc_simple_void_NN(code);
 390   }
 391  }
 392
 393 #if I_HINT_STRUCT
 394  h = PerlMemShared_malloc(sizeof *h);
 395  h->code        = code;
 396 # if I_WORKAROUND_REQUIRE_PROPAGATION
 397  h->require_tag = indirect_require_tag();
 398 # endif /* I_WORKAROUND_REQUIRE_PROPAGATION */
 399 #else  /*  I_HINT_STRUCT */
 400  h = code;
 401 #endif /* !I_HINT_STRUCT */
 402
 403 #if I_THREADSAFE
 404  {
 405   dMY_CXT;
 406   /* We only need for the key to be an unique tag for looking up the value later
 407    * Allocated memory provides convenient unique identifiers, so that's why we
 408    * use the hint as the key itself. */
 409   ptable_hints_store(MY_CXT.tbl, h, h);
 410  }
 411 #endif /* I_THREADSAFE */
 412
 413  return newSViv(PTR2IV(h));
 414 }
 415
 416 STATIC SV *indirect_detag(pTHX_ const SV *hint) {
 417 #define indirect_detag(H) indirect_detag(aTHX_ (H))
 418  indirect_hint_t *h;
 419 #if I_THREADSAFE || I_WORKAROUND_REQUIRE_PROPAGATION
 420  dMY_CXT;
 421 #endif
 422
 423  h = INT2PTR(indirect_hint_t *, SvIVX(hint));
 424 #if I_THREADSAFE
 425  h = ptable_fetch(MY_CXT.tbl, h);
 426 #endif /* I_THREADSAFE */
 427
 428 #if I_WORKAROUND_REQUIRE_PROPAGATION
 429  if (indirect_require_tag() != h->require_tag)
 430   return MY_CXT.global_code;
 431 #endif /* I_WORKAROUND_REQUIRE_PROPAGATION */
 432
 433  return I_HINT_CODE(h);
 434 }
 435
 436 STATIC U32 indirect_hash = 0;
 437
 438 STATIC SV *indirect_hint(pTHX) {
 439 #define indirect_hint() indirect_hint(aTHX)
 440  SV *hint = NULL;
 441
 442  if (IN_PERL_RUNTIME)
 443   return NULL;
 444
 445 #if I_HAS_PERL(5, 10, 0) || defined(PL_parser)
 446  if (!PL_parser)
 447   return NULL;
 448 #endif
 449
 450 #ifdef cop_hints_fetch_pvn
 451  hint = cop_hints_fetch_pvn(PL_curcop, __PACKAGE__, __PACKAGE_LEN__,
 452                                                               indirect_hash, 0);
 453 #elif I_HAS_PERL(5, 9, 5)
 454  hint = Perl_refcounted_he_fetch(aTHX_ PL_curcop->cop_hints_hash,
 455                                        NULL,
 456                                        __PACKAGE__, __PACKAGE_LEN__,
 457                                        0,
 458                                        indirect_hash);
 459 #else
 460  {
 461   SV **val = hv_fetch(GvHV(PL_hintgv), __PACKAGE__, __PACKAGE_LEN__, 0);
 462   if (val)
 463    hint = *val;
 464  }
 465 #endif
 466
 467  if (hint && SvIOK(hint))
 468   return indirect_detag(hint);
 469  else {
 470   dMY_CXT;
 471   return MY_CXT.global_code;
 472  }
 473 }
 474
 475 /* ... op -> source position ............................................... */
 476
 477 STATIC void indirect_map_store(pTHX_ const OP *o, STRLEN pos, SV *sv, line_t line) {
 478 #define indirect_map_store(O, P, N, L) indirect_map_store(aTHX_ (O), (P), (N), (L))
 479  indirect_op_info_t *oi;
 480  const char *s;
 481  STRLEN len;
 482  dMY_CXT;
 483
 484  if (!(oi = ptable_fetch(MY_CXT.map, o))) {
 485   Newx(oi, 1, indirect_op_info_t);
 486   ptable_store(MY_CXT.map, o, oi);
 487   oi->buf  = NULL;
 488   oi->size = 0;
 489  }
 490
 491  if (sv) {
 492   s = SvPV_const(sv, len);
 493  } else {
 494   s   = "{";
 495   len = 1;
 496  }
 497
 498  if (len > oi->size) {
 499   Safefree(oi->buf);
 500   Newx(oi->buf, len, char);
 501   oi->size = len;
 502  }
 503  Copy(s, oi->buf, len, char);
 504
 505  oi->len  = len;
 506  oi->pos  = pos;
 507  oi->line = line;
 508 }
 509
 510 STATIC const indirect_op_info_t *indirect_map_fetch(pTHX_ const OP *o) {
 511 #define indirect_map_fetch(O) indirect_map_fetch(aTHX_ (O))
 512  dMY_CXT;
 513
 514  return ptable_fetch(MY_CXT.map, o);
 515 }
 516
 517 STATIC void indirect_map_delete(pTHX_ const OP *o) {
 518 #define indirect_map_delete(O) indirect_map_delete(aTHX_ (O))
 519  dMY_CXT;
 520
 521  ptable_delete(MY_CXT.map, o);
 522 }
 523
 524 /* --- Check functions ----------------------------------------------------- */
 525
 526 STATIC int indirect_find(pTHX_ SV *name_sv, const char *line_bufptr, STRLEN *name_pos) {
 527 #define indirect_find(NSV, LBP, NP) indirect_find(aTHX_ (NSV), (LBP), (NP))
 528  STRLEN      name_len, line_len;
 529  const char *name, *name_end;
 530  const char *line, *line_end;
 531  const char *p;
 532
 533  line     = SvPV_const(PL_linestr, line_len);
 534  line_end = line + line_len;
 535
 536  name = SvPV_const(name_sv, name_len);
 537  if (name_len >= 1 && *name == '$') {
 538   ++name;
 539   --name_len;
 540   while (line_bufptr < line_end && *line_bufptr != '$')
 541    ++line_bufptr;
 542   if (line_bufptr >= line_end)
 543    return 0;
 544  }
 545  name_end = name + name_len;
 546
 547  p = line_bufptr;
 548  while (1) {
 549   p = ninstr(p, line_end, name, name_end);
 550   if (!p)
 551    return 0;
 552   if (!isALNUM(p[name_len]))
 553    break;
 554   /* p points to a word that has name as prefix, skip the rest of the word */
 555   p += name_len + 1;
 556   while (isALNUM(*p))
 557    ++p;
 558  }
 559
 560  *name_pos = p - line;
 561
 562  return 1;
 563 }
 564
 565 /* ... ck_const ............................................................ */
 566
 567 STATIC OP *(*indirect_old_ck_const)(pTHX_ OP *) = 0;
 568
 569 STATIC OP *indirect_ck_const(pTHX_ OP *o) {
 570  o = indirect_old_ck_const(aTHX_ o);
 571
 572  if (indirect_hint()) {
 573   SV *sv = cSVOPo_sv;
 574
 575   if (SvPOK(sv) && (SvTYPE(sv) >= SVt_PV)) {
 576    STRLEN pos;
 577
 578    if (indirect_find(sv, PL_oldbufptr, &pos)) {
 579     indirect_map_store(o, pos, sv, CopLINE(&PL_compiling));
 580     return o;
 581    }
 582   }
 583  }
 584
 585  indirect_map_delete(o);
 586  return o;
 587 }
 588
 589 /* ... ck_rv2sv ............................................................ */
 590
 591 STATIC OP *(*indirect_old_ck_rv2sv)(pTHX_ OP *) = 0;
 592
 593 STATIC OP *indirect_ck_rv2sv(pTHX_ OP *o) {
 594  if (indirect_hint()) {
 595   OP *op = cUNOPo->op_first;
 596   SV *sv;
 597   const char *name = NULL;
 598   STRLEN pos, len;
 599   OPCODE type = (OPCODE) op->op_type;
 600
 601   switch (type) {
 602    case OP_GV:
 603    case OP_GVSV: {
 604     GV *gv = cGVOPx_gv(op);
 605     name = GvNAME(gv);
 606     len  = GvNAMELEN(gv);
 607     break;
 608    }
 609    default:
 610     if ((PL_opargs[type] & OA_CLASS_MASK) == OA_SVOP) {
 611      SV *nsv = cSVOPx_sv(op);
 612      if (SvPOK(nsv) && (SvTYPE(nsv) >= SVt_PV))
 613       name = SvPV_const(nsv, len);
 614     }
 615   }
 616   if (!name)
 617    goto done;
 618
 619   sv = sv_2mortal(newSVpvn("$", 1));
 620   sv_catpvn_nomg(sv, name, len);
 621   if (!indirect_find(sv, PL_oldbufptr, &pos)) {
 622    /* If it failed, retry without the current stash */
 623    const char *stash = HvNAME_get(PL_curstash);
 624    STRLEN stashlen = HvNAMELEN_get(PL_curstash);
 625
 626    if ((len < stashlen + 2) || strnNE(name, stash, stashlen)
 627        || name[stashlen] != ':' || name[stashlen+1] != ':') {
 628     /* Failed again ? Try to remove main */
 629     stash = "main";
 630     stashlen = 4;
 631     if ((len < stashlen + 2) || strnNE(name, stash, stashlen)
 632         || name[stashlen] != ':' || name[stashlen+1] != ':')
 633      goto done;
 634    }
 635
 636    sv_setpvn(sv, "$", 1);
 637    stashlen += 2;
 638    sv_catpvn_nomg(sv, name + stashlen, len - stashlen);
 639    if (!indirect_find(sv, PL_oldbufptr, &pos))
 640     goto done;
 641   }
 642
 643   o = indirect_old_ck_rv2sv(aTHX_ o);
 644
 645   indirect_map_store(o, pos, sv, CopLINE(&PL_compiling));
 646   return o;
 647  }
 648
 649 done:
 650  o = indirect_old_ck_rv2sv(aTHX_ o);
 651
 652  indirect_map_delete(o);
 653  return o;
 654 }
 655
 656 /* ... ck_padany ........................................................... */
 657
 658 STATIC OP *(*indirect_old_ck_padany)(pTHX_ OP *) = 0;
 659
 660 STATIC OP *indirect_ck_padany(pTHX_ OP *o) {
 661  o = indirect_old_ck_padany(aTHX_ o);
 662
 663  if (indirect_hint()) {
 664   SV *sv;
 665   const char *s = PL_oldbufptr, *t = PL_bufptr - 1;
 666
 667   while (s < t && isSPACE(*s)) ++s;
 668   if (*s == '$' && ++s <= t) {
 669    while (s < t && isSPACE(*s)) ++s;
 670    while (s < t && isSPACE(*t)) --t;
 671    sv = sv_2mortal(newSVpvn("$", 1));
 672    sv_catpvn_nomg(sv, s, t - s + 1);
 673    indirect_map_store(o, s - SvPVX_const(PL_linestr),
 674                          sv, CopLINE(&PL_compiling));
 675    return o;
 676   }
 677  }
 678
 679  indirect_map_delete(o);
 680  return o;
 681 }
 682
 683 /* ... ck_scope ............................................................ */
 684
 685 STATIC OP *(*indirect_old_ck_scope)  (pTHX_ OP *) = 0;
 686 STATIC OP *(*indirect_old_ck_lineseq)(pTHX_ OP *) = 0;
 687
 688 STATIC OP *indirect_ck_scope(pTHX_ OP *o) {
 689  OP *(*old_ck)(pTHX_ OP *) = 0;
 690
 691  switch (o->op_type) {
 692   case OP_SCOPE:   old_ck = indirect_old_ck_scope;   break;
 693   case OP_LINESEQ: old_ck = indirect_old_ck_lineseq; break;
 694  }
 695  o = old_ck(aTHX_ o);
 696
 697  if (indirect_hint()) {
 698   indirect_map_store(o, PL_oldbufptr - SvPVX_const(PL_linestr),
 699                         NULL, CopLINE(&PL_compiling));
 700   return o;
 701  }
 702
 703  indirect_map_delete(o);
 704  return o;
 705 }
 706
 707 /* We don't need to clean the map entries for leave ops because they can only
 708  * be created by mutating from a lineseq. */
 709
 710 /* ... ck_method ........................................................... */
 711
 712 STATIC OP *(*indirect_old_ck_method)(pTHX_ OP *) = 0;
 713
 714 STATIC OP *indirect_ck_method(pTHX_ OP *o) {
 715  if (indirect_hint()) {
 716   OP *op = cUNOPo->op_first;
 717
 718   /* Indirect method call is only possible when the method is a bareword, so
 719    * don't trip up on $obj->$meth. */
 720   if (op && op->op_type == OP_CONST) {
 721    const indirect_op_info_t *oi = indirect_map_fetch(op);
 722    STRLEN pos;
 723    line_t line;
 724    SV *sv;
 725
 726    if (!oi)
 727     goto done;
 728
 729    sv   = sv_2mortal(newSVpvn(oi->buf, oi->len));
 730    pos  = oi->pos;
 731    /* Keep the old line so that we really point to the first line of the
 732     * expression. */
 733    line = oi->line;
 734
 735    o = indirect_old_ck_method(aTHX_ o);
 736    /* o may now be a method_named */
 737
 738    indirect_map_store(o, pos, sv, line);
 739    return o;
 740   }
 741  }
 742
 743 done:
 744  o = indirect_old_ck_method(aTHX_ o);
 745
 746  indirect_map_delete(o);
 747  return o;
 748 }
 749
 750 /* ... ck_method_named ..................................................... */
 751
 752 /* "use foo/no foo" compiles its call to import/unimport directly to a
 753  * method_named op. */
 754
 755 STATIC OP *(*indirect_old_ck_method_named)(pTHX_ OP *) = 0;
 756
 757 STATIC OP *indirect_ck_method_named(pTHX_ OP *o) {
 758  if (indirect_hint()) {
 759   STRLEN pos;
 760   line_t line;
 761   SV *sv;
 762
 763   sv = cSVOPo_sv;
 764   if (!SvPOK(sv) || (SvTYPE(sv) < SVt_PV))
 765    goto done;
 766   sv = sv_mortalcopy(sv);
 767
 768   if (!indirect_find(sv, PL_oldbufptr, &pos))
 769    goto done;
 770   line = CopLINE(&PL_compiling);
 771
 772   o = indirect_old_ck_method_named(aTHX_ o);
 773
 774   indirect_map_store(o, pos, sv, line);
 775   return o;
 776  }
 777
 778 done:
 779  o = indirect_old_ck_method_named(aTHX_ o);
 780
 781  indirect_map_delete(o);
 782  return o;
 783 }
 784
 785 /* ... ck_entersub ......................................................... */
 786
 787 STATIC OP *(*indirect_old_ck_entersub)(pTHX_ OP *) = 0;
 788
 789 STATIC OP *indirect_ck_entersub(pTHX_ OP *o) {
 790  SV *code = indirect_hint();
 791
 792  o = indirect_old_ck_entersub(aTHX_ o);
 793
 794  if (code) {
 795   const indirect_op_info_t *moi, *ooi;
 796   OP     *mop, *oop;
 797   LISTOP *lop;
 798
 799   oop = o;
 800   do {
 801    lop = (LISTOP *) oop;
 802    if (!(lop->op_flags & OPf_KIDS))
 803     goto done;
 804    oop = lop->op_first;
 805   } while (oop->op_type != OP_PUSHMARK);
 806   oop = oop->op_sibling;
 807   mop = lop->op_last;
 808
 809   if (!oop)
 810    goto done;
 811
 812   switch (oop->op_type) {
 813    case OP_CONST:
 814    case OP_RV2SV:
 815    case OP_PADSV:
 816    case OP_SCOPE:
 817    case OP_LEAVE:
 818     break;
 819    default:
 820     goto done;
 821   }
 822
 823   if (mop->op_type == OP_METHOD)
 824    mop = cUNOPx(mop)->op_first;
 825   else if (mop->op_type != OP_METHOD_NAMED)
 826    goto done;
 827
 828   moi = indirect_map_fetch(mop);
 829   if (!moi)
 830    goto done;
 831
 832   ooi = indirect_map_fetch(oop);
 833   if (!ooi)
 834    goto done;
 835
 836   /* When positions are identical, the method and the object must have the
 837    * same name. But it also means that it is an indirect call, as "foo->foo"
 838    * results in different positions. */
 839   if (   moi->line < ooi->line
 840       || (moi->line == ooi->line && moi->pos <= ooi->pos)) {
 841    SV *file;
 842    dSP;
 843
 844    ENTER;
 845    SAVETMPS;
 846
 847 #ifdef USE_ITHREADS
 848    file = sv_2mortal(newSVpv(CopFILE(&PL_compiling), 0));
 849 #else
 850    file = sv_mortalcopy(CopFILESV(&PL_compiling));
 851 #endif
 852
 853    PUSHMARK(SP);
 854    EXTEND(SP, 4);
 855    mPUSHp(ooi->buf, ooi->len);
 856    mPUSHp(moi->buf, moi->len);
 857    PUSHs(file);
 858    mPUSHu(moi->line);
 859    PUTBACK;
 860
 861    call_sv(code, G_VOID);
 862
 863    PUTBACK;
 864
 865    FREETMPS;
 866    LEAVE;
 867   }
 868  }
 869
 870 done:
 871  return o;
 872 }
 873
 874 STATIC U32 indirect_initialized = 0;
 875
 876 STATIC void indirect_teardown(pTHX_ void *root) {
 877  if (!indirect_initialized)
 878   return;
 879
 880 #if I_MULTIPLICITY
 881  if (aTHX != root)
 882   return;
 883 #endif
 884
 885  {
 886   dMY_CXT;
 887   ptable_free(MY_CXT.map);
 888 #if I_THREADSAFE
 889   ptable_hints_free(MY_CXT.tbl);
 890 #endif
 891  }
 892
 893  indirect_ck_restore(OP_CONST,   &indirect_old_ck_const);
 894  indirect_ck_restore(OP_RV2SV,   &indirect_old_ck_rv2sv);
 895  indirect_ck_restore(OP_PADANY,  &indirect_old_ck_padany);
 896  indirect_ck_restore(OP_SCOPE,   &indirect_old_ck_scope);
 897  indirect_ck_restore(OP_LINESEQ, &indirect_old_ck_lineseq);
 898
 899  indirect_ck_restore(OP_METHOD,       &indirect_old_ck_method);
 900  indirect_ck_restore(OP_METHOD_NAMED, &indirect_old_ck_method_named);
 901  indirect_ck_restore(OP_ENTERSUB,     &indirect_old_ck_entersub);
 902
 903  indirect_initialized = 0;
 904 }
 905
 906 STATIC void indirect_setup(pTHX) {
 907 #define indirect_setup() indirect_setup(aTHX)
 908  if (indirect_initialized)
 909   return;
 910
 911  {
 912   MY_CXT_INIT;
 913 #if I_THREADSAFE
 914   MY_CXT.tbl         = ptable_new();
 915   MY_CXT.owner       = aTHX;
 916 #endif
 917   MY_CXT.map         = ptable_new();
 918   MY_CXT.global_code = NULL;
 919  }
 920
 921  indirect_ck_replace(OP_CONST,   indirect_ck_const,  &indirect_old_ck_const);
 922  indirect_ck_replace(OP_RV2SV,   indirect_ck_rv2sv,  &indirect_old_ck_rv2sv);
 923  indirect_ck_replace(OP_PADANY,  indirect_ck_padany, &indirect_old_ck_padany);
 924  indirect_ck_replace(OP_SCOPE,   indirect_ck_scope,  &indirect_old_ck_scope);
 925  indirect_ck_replace(OP_LINESEQ, indirect_ck_scope,  &indirect_old_ck_lineseq);
 926
 927  indirect_ck_replace(OP_METHOD,       indirect_ck_method,
 928                                       &indirect_old_ck_method);
 929  indirect_ck_replace(OP_METHOD_NAMED, indirect_ck_method_named,
 930                                       &indirect_old_ck_method_named);
 931  indirect_ck_replace(OP_ENTERSUB,     indirect_ck_entersub,
 932                                       &indirect_old_ck_entersub);
 933
 934 #if I_MULTIPLICITY
 935  call_atexit(indirect_teardown, aTHX);
 936 #else
 937  call_atexit(indirect_teardown, NULL);
 938 #endif
 939
 940  indirect_initialized = 1;
 941 }
 942
 943 STATIC U32 indirect_booted = 0;
 944
 945 /* --- XS ------------------------------------------------------------------ */
 946
 947 MODULE = indirect      PACKAGE = indirect
 948
 949 PROTOTYPES: ENABLE
 950
 951 BOOT:
 952 {
 953  if (!indirect_booted++) {
 954   HV *stash;
 955
 956   PERL_HASH(indirect_hash, __PACKAGE__, __PACKAGE_LEN__);
 957
 958   stash = gv_stashpvn(__PACKAGE__, __PACKAGE_LEN__, 1);
 959   newCONSTSUB(stash, "I_THREADSAFE", newSVuv(I_THREADSAFE));
 960   newCONSTSUB(stash, "I_FORKSAFE",   newSVuv(I_FORKSAFE));
 961  }
 962
 963  indirect_setup();
 964 }
 965
 966 #if I_THREADSAFE
 967
 968 void
 969 CLONE(...)
 970 PROTOTYPE: DISABLE
 971 PREINIT:
 972  ptable *t;
 973  SV     *global_code_dup;
 974 PPCODE:
 975  {
 976   my_cxt_t ud;
 977   dMY_CXT;
 978   ud.tbl   = t = ptable_new();
 979   ud.owner = MY_CXT.owner;
 980   ptable_walk(MY_CXT.tbl, indirect_ptable_clone, &ud);
 981   global_code_dup = indirect_clone(MY_CXT.global_code, MY_CXT.owner);
 982  }
 983  {
 984   MY_CXT_CLONE;
 985   MY_CXT.map         = ptable_new();
 986   MY_CXT.tbl         = t;
 987   MY_CXT.owner       = aTHX;
 988   MY_CXT.global_code = global_code_dup;
 989  }
 990  reap(3, indirect_thread_cleanup, NULL);
 991  XSRETURN(0);
 992
 993 #endif
 994
 995 SV *
 996 _tag(SV *value)
 997 PROTOTYPE: $
 998 CODE:
 999  RETVAL = indirect_tag(value);
1000 OUTPUT:
1001  RETVAL
1002
1003 void
1004 _global(SV *code)
1005 PROTOTYPE: $
1006 PPCODE:
1007  if (!SvOK(code))
1008   code = NULL;
1009  else if (SvROK(code))
1010   code = SvRV(code);
1011  {
1012   dMY_CXT;
1013   SvREFCNT_dec(MY_CXT.global_code);
1014   MY_CXT.global_code = SvREFCNT_inc(code);
1015  }
1016  XSRETURN(0);