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 #ifndef OP_SIBLING
  67 # define OP_SIBLING(O) ((O)->op_sibling)
  68 #endif
  69
  70 #define I_HAS_PERL(R, V, S) (PERL_REVISION > (R) || (PERL_REVISION == (R) && (PERL_VERSION > (V) || (PERL_VERSION == (V) && (PERL_SUBVERSION >= (S))))))
  71
  72 #if I_HAS_PERL(5, 10, 0) || defined(PL_parser)
  73 # ifndef PL_linestr
  74 #  define PL_linestr PL_parser->linestr
  75 # endif
  76 # ifndef PL_bufptr
  77 #  define PL_bufptr PL_parser->bufptr
  78 # endif
  79 # ifndef PL_oldbufptr
  80 #  define PL_oldbufptr PL_parser->oldbufptr
  81 # endif
  82 # ifndef PL_lex_inwhat
  83 #  define PL_lex_inwhat PL_parser->lex_inwhat
  84 # endif
  85 #else
  86 # ifndef PL_linestr
  87 #  define PL_linestr PL_Ilinestr
  88 # endif
  89 # ifndef PL_bufptr
  90 #  define PL_bufptr PL_Ibufptr
  91 # endif
  92 # ifndef PL_oldbufptr
  93 #  define PL_oldbufptr PL_Ioldbufptr
  94 # endif
  95 # ifndef PL_lex_inwhat
  96 #  define PL_lex_inwhat PL_Ilex_inwhat
  97 # endif
  98 #endif
  99
 100 #ifndef I_WORKAROUND_REQUIRE_PROPAGATION
 101 # define I_WORKAROUND_REQUIRE_PROPAGATION !I_HAS_PERL(5, 10, 1)
 102 #endif
 103
 104 /* ... Thread safety and multiplicity ...................................... */
 105
 106 /* Safe unless stated otherwise in Makefile.PL */
 107 #ifndef I_FORKSAFE
 108 # define I_FORKSAFE 1
 109 #endif
 110
 111 #ifndef I_MULTIPLICITY
 112 # if defined(MULTIPLICITY) || defined(PERL_IMPLICIT_CONTEXT)
 113 #  define I_MULTIPLICITY 1
 114 # else
 115 #  define I_MULTIPLICITY 0
 116 # endif
 117 #endif
 118 #if I_MULTIPLICITY && !defined(tTHX)
 119 # define tTHX PerlInterpreter*
 120 #endif
 121
 122 #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))
 123 # define I_THREADSAFE 1
 124 # ifndef MY_CXT_CLONE
 125 #  define MY_CXT_CLONE \
 126     dMY_CXT_SV;                                                      \
 127     my_cxt_t *my_cxtp = (my_cxt_t*)SvPVX(newSV(sizeof(my_cxt_t)-1)); \
 128     Copy(INT2PTR(my_cxt_t*, SvUV(my_cxt_sv)), my_cxtp, 1, my_cxt_t); \
 129     sv_setuv(my_cxt_sv, PTR2UV(my_cxtp))
 130 # endif
 131 #else
 132 # define I_THREADSAFE 0
 133 # undef  dMY_CXT
 134 # define dMY_CXT      dNOOP
 135 # undef  MY_CXT
 136 # define MY_CXT       indirect_globaldata
 137 # undef  START_MY_CXT
 138 # define START_MY_CXT STATIC my_cxt_t MY_CXT;
 139 # undef  MY_CXT_INIT
 140 # define MY_CXT_INIT  NOOP
 141 # undef  MY_CXT_CLONE
 142 # define MY_CXT_CLONE NOOP
 143 #endif
 144
 145 #if defined(OP_CHECK_MUTEX_LOCK) && defined(OP_CHECK_MUTEX_UNLOCK)
 146 # define I_CHECK_MUTEX_LOCK   OP_CHECK_MUTEX_LOCK
 147 # define I_CHECK_MUTEX_UNLOCK OP_CHECK_MUTEX_UNLOCK
 148 #else
 149 # define I_CHECK_MUTEX_LOCK   OP_REFCNT_LOCK
 150 # define I_CHECK_MUTEX_UNLOCK OP_REFCNT_UNLOCK
 151 #endif
 152
 153 typedef OP *(*indirect_ck_t)(pTHX_ OP *);
 154
 155 #ifdef wrap_op_checker
 156
 157 # define indirect_ck_replace(T, NC, OCP) wrap_op_checker((T), (NC), (OCP))
 158
 159 #else
 160
 161 STATIC void indirect_ck_replace(pTHX_ OPCODE type, indirect_ck_t new_ck, indirect_ck_t *old_ck_p) {
 162 #define indirect_ck_replace(T, NC, OCP) indirect_ck_replace(aTHX_ (T), (NC), (OCP))
 163  I_CHECK_MUTEX_LOCK;
 164  if (!*old_ck_p) {
 165   *old_ck_p      = PL_check[type];
 166   PL_check[type] = new_ck;
 167  }
 168  I_CHECK_MUTEX_UNLOCK;
 169 }
 170
 171 #endif
 172
 173 STATIC void indirect_ck_restore(pTHX_ OPCODE type, indirect_ck_t *old_ck_p) {
 174 #define indirect_ck_restore(T, OCP) indirect_ck_restore(aTHX_ (T), (OCP))
 175  I_CHECK_MUTEX_LOCK;
 176  if (*old_ck_p) {
 177   PL_check[type] = *old_ck_p;
 178   *old_ck_p      = 0;
 179  }
 180  I_CHECK_MUTEX_UNLOCK;
 181 }
 182
 183 /* --- Helpers ------------------------------------------------------------- */
 184
 185 /* ... Thread-safe hints ................................................... */
 186
 187 #if I_WORKAROUND_REQUIRE_PROPAGATION
 188
 189 typedef struct {
 190  SV *code;
 191  IV  require_tag;
 192 } indirect_hint_t;
 193
 194 #define I_HINT_STRUCT 1
 195
 196 #define I_HINT_CODE(H) ((H)->code)
 197
 198 #define I_HINT_FREE(H) {   \
 199  indirect_hint_t *h = (H); \
 200  SvREFCNT_dec(h->code);    \
 201  PerlMemShared_free(h);    \
 202 }
 203
 204 #else  /*  I_WORKAROUND_REQUIRE_PROPAGATION */
 205
 206 typedef SV indirect_hint_t;
 207
 208 #define I_HINT_STRUCT 0
 209
 210 #define I_HINT_CODE(H) (H)
 211
 212 #define I_HINT_FREE(H) SvREFCNT_dec(H);
 213
 214 #endif /* !I_WORKAROUND_REQUIRE_PROPAGATION */
 215
 216 #if I_THREADSAFE
 217
 218 #define PTABLE_NAME        ptable_hints
 219 #define PTABLE_VAL_FREE(V) I_HINT_FREE(V)
 220
 221 #define pPTBL  pTHX
 222 #define pPTBL_ pTHX_
 223 #define aPTBL  aTHX
 224 #define aPTBL_ aTHX_
 225
 226 #include "ptable.h"
 227
 228 #define ptable_hints_store(T, K, V) ptable_hints_store(aTHX_ (T), (K), (V))
 229 #define ptable_hints_free(T)        ptable_hints_free(aTHX_ (T))
 230
 231 #endif /* I_THREADSAFE */
 232
 233 /* Define the op->str ptable here because we need to be able to clean it during
 234  * thread cleanup. */
 235
 236 typedef struct {
 237  char   *buf;
 238  STRLEN  pos;
 239  STRLEN  size;
 240  STRLEN  len;
 241  line_t  line;
 242 } indirect_op_info_t;
 243
 244 #define PTABLE_NAME        ptable
 245 #define PTABLE_VAL_FREE(V) if (V) { Safefree(((indirect_op_info_t *) (V))->buf); Safefree(V); }
 246
 247 #define pPTBL  pTHX
 248 #define pPTBL_ pTHX_
 249 #define aPTBL  aTHX
 250 #define aPTBL_ aTHX_
 251
 252 #include "ptable.h"
 253
 254 #define ptable_store(T, K, V) ptable_store(aTHX_ (T), (K), (V))
 255 #define ptable_delete(T, K)   ptable_delete(aTHX_ (T), (K))
 256 #define ptable_clear(T)       ptable_clear(aTHX_ (T))
 257 #define ptable_free(T)        ptable_free(aTHX_ (T))
 258
 259 #define MY_CXT_KEY __PACKAGE__ "::_guts" XS_VERSION
 260
 261 typedef struct {
 262 #if I_THREADSAFE
 263  ptable *tbl; /* It really is a ptable_hints */
 264  tTHX    owner;
 265 #endif
 266  ptable *map;
 267  SV     *global_code;
 268 } my_cxt_t;
 269
 270 START_MY_CXT
 271
 272 #if I_THREADSAFE
 273
 274 typedef struct {
 275  ptable *tbl;
 276 #if I_HAS_PERL(5, 13, 2)
 277  CLONE_PARAMS *params;
 278 #else
 279  CLONE_PARAMS params;
 280 #endif
 281 } indirect_ptable_clone_ud;
 282
 283 #if I_HAS_PERL(5, 13, 2)
 284 # define indirect_ptable_clone_ud_init(U, T, O) \
 285    (U).tbl    = (T); \
 286    (U).params = Perl_clone_params_new((O), aTHX)
 287 # define indirect_ptable_clone_ud_deinit(U) Perl_clone_params_del((U).params)
 288 # define indirect_dup_inc(S, U)             SvREFCNT_inc(sv_dup((S), (U)->params))
 289 #else
 290 # define indirect_ptable_clone_ud_init(U, T, O) \
 291    (U).tbl               = (T);     \
 292    (U).params.stashes    = newAV(); \
 293    (U).params.flags      = 0;       \
 294    (U).params.proto_perl = (O)
 295 # define indirect_ptable_clone_ud_deinit(U) SvREFCNT_dec((U).params.stashes)
 296 # define indirect_dup_inc(S, U)             SvREFCNT_inc(sv_dup((S), &((U)->params)))
 297 #endif
 298
 299 STATIC void indirect_ptable_clone(pTHX_ ptable_ent *ent, void *ud_) {
 300  indirect_ptable_clone_ud *ud = ud_;
 301  indirect_hint_t          *h1 = ent->val;
 302  indirect_hint_t          *h2;
 303
 304 #if I_HINT_STRUCT
 305
 306  h2              = PerlMemShared_malloc(sizeof *h2);
 307  h2->code        = indirect_dup_inc(h1->code, ud);
 308 #if I_WORKAROUND_REQUIRE_PROPAGATION
 309  h2->require_tag = PTR2IV(indirect_dup_inc(INT2PTR(SV *, h1->require_tag), ud));
 310 #endif
 311
 312 #else  /*  I_HINT_STRUCT */
 313
 314  h2 = indirect_dup_inc(h1, ud);
 315
 316 #endif /* !I_HINT_STRUCT */
 317
 318  ptable_hints_store(ud->tbl, ent->key, h2);
 319 }
 320
 321 STATIC void indirect_thread_cleanup(pTHX_ void *ud) {
 322  dMY_CXT;
 323
 324  SvREFCNT_dec(MY_CXT.global_code);
 325  MY_CXT.global_code = NULL;
 326  ptable_free(MY_CXT.map);
 327  MY_CXT.map = NULL;
 328  ptable_hints_free(MY_CXT.tbl);
 329  MY_CXT.tbl = NULL;
 330 }
 331
 332 STATIC int indirect_endav_free(pTHX_ SV *sv, MAGIC *mg) {
 333  SAVEDESTRUCTOR_X(indirect_thread_cleanup, NULL);
 334
 335  return 0;
 336 }
 337
 338 STATIC MGVTBL indirect_endav_vtbl = {
 339  0,
 340  0,
 341  0,
 342  0,
 343  indirect_endav_free
 344 #if MGf_COPY
 345  , 0
 346 #endif
 347 #if MGf_DUP
 348  , 0
 349 #endif
 350 #if MGf_LOCAL
 351  , 0
 352 #endif
 353 };
 354
 355 #endif /* I_THREADSAFE */
 356
 357 #if I_WORKAROUND_REQUIRE_PROPAGATION
 358 STATIC IV indirect_require_tag(pTHX) {
 359 #define indirect_require_tag() indirect_require_tag(aTHX)
 360  const CV *cv, *outside;
 361
 362  cv = PL_compcv;
 363
 364  if (!cv) {
 365   /* If for some reason the pragma is operational at run-time, try to discover
 366    * the current cv in use. */
 367   const PERL_SI *si;
 368
 369   for (si = PL_curstackinfo; si; si = si->si_prev) {
 370    I32 cxix;
 371
 372    for (cxix = si->si_cxix; cxix >= 0; --cxix) {
 373     const PERL_CONTEXT *cx = si->si_cxstack + cxix;
 374
 375     switch (CxTYPE(cx)) {
 376      case CXt_SUB:
 377      case CXt_FORMAT:
 378       /* The propagation workaround is only needed up to 5.10.0 and at that
 379        * time format and sub contexts were still identical. And even later the
 380        * cv members offsets should have been kept the same. */
 381       cv = cx->blk_sub.cv;
 382       goto get_enclosing_cv;
 383      case CXt_EVAL:
 384       cv = cx->blk_eval.cv;
 385       goto get_enclosing_cv;
 386      default:
 387       break;
 388     }
 389    }
 390   }
 391
 392   cv = PL_main_cv;
 393  }
 394
 395 get_enclosing_cv:
 396  for (outside = CvOUTSIDE(cv); outside; outside = CvOUTSIDE(cv))
 397   cv = outside;
 398
 399  return PTR2IV(cv);
 400 }
 401 #endif /* I_WORKAROUND_REQUIRE_PROPAGATION */
 402
 403 STATIC SV *indirect_tag(pTHX_ SV *value) {
 404 #define indirect_tag(V) indirect_tag(aTHX_ (V))
 405  indirect_hint_t *h;
 406  SV              *code = NULL;
 407 #if I_THREADSAFE
 408  dMY_CXT;
 409
 410  if (!MY_CXT.tbl)
 411   return newSViv(0);
 412 #endif /* I_THREADSAFE */
 413
 414  if (SvROK(value)) {
 415   value = SvRV(value);
 416   if (SvTYPE(value) >= SVt_PVCV) {
 417    code = value;
 418    SvREFCNT_inc_simple_void_NN(code);
 419   }
 420  }
 421
 422 #if I_HINT_STRUCT
 423  h = PerlMemShared_malloc(sizeof *h);
 424  h->code        = code;
 425 # if I_WORKAROUND_REQUIRE_PROPAGATION
 426  h->require_tag = indirect_require_tag();
 427 # endif /* I_WORKAROUND_REQUIRE_PROPAGATION */
 428 #else  /*  I_HINT_STRUCT */
 429  h = code;
 430 #endif /* !I_HINT_STRUCT */
 431
 432 #if I_THREADSAFE
 433  /* We only need for the key to be an unique tag for looking up the value later
 434   * Allocated memory provides convenient unique identifiers, so that's why we
 435   * use the hint as the key itself. */
 436  ptable_hints_store(MY_CXT.tbl, h, h);
 437 #endif /* I_THREADSAFE */
 438
 439  return newSViv(PTR2IV(h));
 440 }
 441
 442 STATIC SV *indirect_detag(pTHX_ const SV *hint) {
 443 #define indirect_detag(H) indirect_detag(aTHX_ (H))
 444  indirect_hint_t *h;
 445 #if I_THREADSAFE || I_WORKAROUND_REQUIRE_PROPAGATION
 446  dMY_CXT;
 447 #endif
 448
 449 #if I_THREADSAFE
 450  if (!MY_CXT.tbl)
 451   return NULL;
 452 #endif /* I_THREADSAFE */
 453
 454  h = INT2PTR(indirect_hint_t *, SvIVX(hint));
 455 #if I_THREADSAFE
 456  h = ptable_fetch(MY_CXT.tbl, h);
 457 #endif /* I_THREADSAFE */
 458
 459 #if I_WORKAROUND_REQUIRE_PROPAGATION
 460  if (indirect_require_tag() != h->require_tag)
 461   return MY_CXT.global_code;
 462 #endif /* I_WORKAROUND_REQUIRE_PROPAGATION */
 463
 464  return I_HINT_CODE(h);
 465 }
 466
 467 STATIC U32 indirect_hash = 0;
 468
 469 STATIC SV *indirect_hint(pTHX) {
 470 #define indirect_hint() indirect_hint(aTHX)
 471  SV *hint = NULL;
 472
 473  if (IN_PERL_RUNTIME)
 474   return NULL;
 475
 476 #if I_HAS_PERL(5, 10, 0) || defined(PL_parser)
 477  if (!PL_parser)
 478   return NULL;
 479 #endif
 480
 481 #ifdef cop_hints_fetch_pvn
 482  hint = cop_hints_fetch_pvn(PL_curcop, __PACKAGE__, __PACKAGE_LEN__,
 483                                                               indirect_hash, 0);
 484 #elif I_HAS_PERL(5, 9, 5)
 485  hint = Perl_refcounted_he_fetch(aTHX_ PL_curcop->cop_hints_hash,
 486                                        NULL,
 487                                        __PACKAGE__, __PACKAGE_LEN__,
 488                                        0,
 489                                        indirect_hash);
 490 #else
 491  {
 492   SV **val = hv_fetch(GvHV(PL_hintgv), __PACKAGE__, __PACKAGE_LEN__, 0);
 493   if (val)
 494    hint = *val;
 495  }
 496 #endif
 497
 498  if (hint && SvIOK(hint))
 499   return indirect_detag(hint);
 500  else {
 501   dMY_CXT;
 502   return MY_CXT.global_code;
 503  }
 504 }
 505
 506 /* ... op -> source position ............................................... */
 507
 508 STATIC void indirect_map_store(pTHX_ const OP *o, STRLEN pos, SV *sv, line_t line) {
 509 #define indirect_map_store(O, P, N, L) indirect_map_store(aTHX_ (O), (P), (N), (L))
 510  indirect_op_info_t *oi;
 511  const char *s;
 512  STRLEN len;
 513  dMY_CXT;
 514
 515  /* No need to check for MY_CXT.map != NULL because this code path is always
 516   * guarded by indirect_hint(). */
 517
 518  if (!(oi = ptable_fetch(MY_CXT.map, o))) {
 519   Newx(oi, 1, indirect_op_info_t);
 520   ptable_store(MY_CXT.map, o, oi);
 521   oi->buf  = NULL;
 522   oi->size = 0;
 523  }
 524
 525  if (sv) {
 526   s = SvPV_const(sv, len);
 527  } else {
 528   s   = "{";
 529   len = 1;
 530  }
 531
 532  if (len > oi->size) {
 533   Safefree(oi->buf);
 534   Newx(oi->buf, len, char);
 535   oi->size = len;
 536  }
 537  Copy(s, oi->buf, len, char);
 538
 539  oi->len  = len;
 540  oi->pos  = pos;
 541  oi->line = line;
 542 }
 543
 544 STATIC const indirect_op_info_t *indirect_map_fetch(pTHX_ const OP *o) {
 545 #define indirect_map_fetch(O) indirect_map_fetch(aTHX_ (O))
 546  dMY_CXT;
 547
 548  /* No need to check for MY_CXT.map != NULL because this code path is always
 549   * guarded by indirect_hint(). */
 550
 551  return ptable_fetch(MY_CXT.map, o);
 552 }
 553
 554 STATIC void indirect_map_delete(pTHX_ const OP *o) {
 555 #define indirect_map_delete(O) indirect_map_delete(aTHX_ (O))
 556  dMY_CXT;
 557
 558  if (MY_CXT.map)
 559   ptable_delete(MY_CXT.map, o);
 560 }
 561
 562 /* --- Check functions ----------------------------------------------------- */
 563
 564 STATIC int indirect_find(pTHX_ SV *name_sv, const char *line_bufptr, STRLEN *name_pos) {
 565 #define indirect_find(NSV, LBP, NP) indirect_find(aTHX_ (NSV), (LBP), (NP))
 566  STRLEN      name_len, line_len;
 567  const char *name, *name_end;
 568  const char *line, *line_end;
 569  const char *p;
 570
 571  line     = SvPV_const(PL_linestr, line_len);
 572  line_end = line + line_len;
 573
 574  name = SvPV_const(name_sv, name_len);
 575  if (name_len >= 1 && *name == '$') {
 576   ++name;
 577   --name_len;
 578   while (line_bufptr < line_end && *line_bufptr != '$')
 579    ++line_bufptr;
 580   if (line_bufptr >= line_end)
 581    return 0;
 582  }
 583  name_end = name + name_len;
 584
 585  p = line_bufptr;
 586  while (1) {
 587   p = ninstr(p, line_end, name, name_end);
 588   if (!p)
 589    return 0;
 590   if (!isALNUM(p[name_len]))
 591    break;
 592   /* p points to a word that has name as prefix, skip the rest of the word */
 593   p += name_len + 1;
 594   while (isALNUM(*p))
 595    ++p;
 596  }
 597
 598  *name_pos = p - line;
 599
 600  return 1;
 601 }
 602
 603 /* ... ck_const ............................................................ */
 604
 605 STATIC OP *(*indirect_old_ck_const)(pTHX_ OP *) = 0;
 606
 607 STATIC OP *indirect_ck_const(pTHX_ OP *o) {
 608  o = indirect_old_ck_const(aTHX_ o);
 609
 610  if (indirect_hint()) {
 611   SV *sv = cSVOPo_sv;
 612
 613   if (SvPOK(sv) && (SvTYPE(sv) >= SVt_PV)) {
 614    STRLEN pos;
 615
 616    if (indirect_find(sv, PL_oldbufptr, &pos)) {
 617     STRLEN len;
 618
 619     /* If the constant is equal to the current package name, try to look for
 620      * a "__PACKAGE__" coming before what we got. We only need to check this
 621      * when we already had a match because __PACKAGE__ can only appear in
 622      * direct method calls ("new __PACKAGE__" is a syntax error). */
 623     len = SvCUR(sv);
 624     if (PL_curstash
 625         && len == (STRLEN) HvNAMELEN_get(PL_curstash)
 626         && memcmp(SvPVX(sv), HvNAME_get(PL_curstash), len) == 0) {
 627      STRLEN pos_pkg;
 628      SV    *pkg = sv_newmortal();
 629      sv_setpvn(pkg, "__PACKAGE__", sizeof("__PACKAGE__")-1);
 630
 631      if (indirect_find(pkg, PL_oldbufptr, &pos_pkg) && pos_pkg < pos) {
 632       sv  = pkg;
 633       pos = pos_pkg;
 634      }
 635     }
 636
 637     indirect_map_store(o, pos, sv, CopLINE(&PL_compiling));
 638     return o;
 639    }
 640   }
 641  }
 642
 643  indirect_map_delete(o);
 644  return o;
 645 }
 646
 647 /* ... ck_rv2sv ............................................................ */
 648
 649 STATIC OP *(*indirect_old_ck_rv2sv)(pTHX_ OP *) = 0;
 650
 651 STATIC OP *indirect_ck_rv2sv(pTHX_ OP *o) {
 652  if (indirect_hint()) {
 653   OP *op = cUNOPo->op_first;
 654   SV *sv;
 655   const char *name = NULL;
 656   STRLEN pos, len;
 657   OPCODE type = (OPCODE) op->op_type;
 658
 659   switch (type) {
 660    case OP_GV:
 661    case OP_GVSV: {
 662     GV *gv = cGVOPx_gv(op);
 663     name = GvNAME(gv);
 664     len  = GvNAMELEN(gv);
 665     break;
 666    }
 667    default:
 668     if ((PL_opargs[type] & OA_CLASS_MASK) == OA_SVOP) {
 669      SV *nsv = cSVOPx_sv(op);
 670      if (SvPOK(nsv) && (SvTYPE(nsv) >= SVt_PV))
 671       name = SvPV_const(nsv, len);
 672     }
 673   }
 674   if (!name)
 675    goto done;
 676
 677   sv = sv_2mortal(newSVpvn("$", 1));
 678   sv_catpvn_nomg(sv, name, len);
 679   if (!indirect_find(sv, PL_oldbufptr, &pos)) {
 680    /* If it failed, retry without the current stash */
 681    const char *stash = HvNAME_get(PL_curstash);
 682    STRLEN stashlen = HvNAMELEN_get(PL_curstash);
 683
 684    if ((len < stashlen + 2) || strnNE(name, stash, stashlen)
 685        || name[stashlen] != ':' || name[stashlen+1] != ':') {
 686     /* Failed again ? Try to remove main */
 687     stash = "main";
 688     stashlen = 4;
 689     if ((len < stashlen + 2) || strnNE(name, stash, stashlen)
 690         || name[stashlen] != ':' || name[stashlen+1] != ':')
 691      goto done;
 692    }
 693
 694    sv_setpvn(sv, "$", 1);
 695    stashlen += 2;
 696    sv_catpvn_nomg(sv, name + stashlen, len - stashlen);
 697    if (!indirect_find(sv, PL_oldbufptr, &pos))
 698     goto done;
 699   }
 700
 701   o = indirect_old_ck_rv2sv(aTHX_ o);
 702
 703   indirect_map_store(o, pos, sv, CopLINE(&PL_compiling));
 704   return o;
 705  }
 706
 707 done:
 708  o = indirect_old_ck_rv2sv(aTHX_ o);
 709
 710  indirect_map_delete(o);
 711  return o;
 712 }
 713
 714 /* ... ck_padany ........................................................... */
 715
 716 STATIC OP *(*indirect_old_ck_padany)(pTHX_ OP *) = 0;
 717
 718 STATIC OP *indirect_ck_padany(pTHX_ OP *o) {
 719  o = indirect_old_ck_padany(aTHX_ o);
 720
 721  if (indirect_hint()) {
 722   SV *sv;
 723   const char *s = PL_oldbufptr, *t = PL_bufptr - 1;
 724
 725   while (s < t && isSPACE(*s)) ++s;
 726   if (*s == '$' && ++s <= t) {
 727    while (s < t && isSPACE(*s)) ++s;
 728    while (s < t && isSPACE(*t)) --t;
 729    sv = sv_2mortal(newSVpvn("$", 1));
 730    sv_catpvn_nomg(sv, s, t - s + 1);
 731    indirect_map_store(o, s - SvPVX_const(PL_linestr),
 732                          sv, CopLINE(&PL_compiling));
 733    return o;
 734   }
 735  }
 736
 737  indirect_map_delete(o);
 738  return o;
 739 }
 740
 741 /* ... ck_scope ............................................................ */
 742
 743 STATIC OP *(*indirect_old_ck_scope)  (pTHX_ OP *) = 0;
 744 STATIC OP *(*indirect_old_ck_lineseq)(pTHX_ OP *) = 0;
 745
 746 STATIC OP *indirect_ck_scope(pTHX_ OP *o) {
 747  OP *(*old_ck)(pTHX_ OP *) = 0;
 748
 749  switch (o->op_type) {
 750   case OP_SCOPE:   old_ck = indirect_old_ck_scope;   break;
 751   case OP_LINESEQ: old_ck = indirect_old_ck_lineseq; break;
 752  }
 753  o = old_ck(aTHX_ o);
 754
 755  if (indirect_hint()) {
 756   indirect_map_store(o, PL_oldbufptr - SvPVX_const(PL_linestr),
 757                         NULL, CopLINE(&PL_compiling));
 758   return o;
 759  }
 760
 761  indirect_map_delete(o);
 762  return o;
 763 }
 764
 765 /* We don't need to clean the map entries for leave ops because they can only
 766  * be created by mutating from a lineseq. */
 767
 768 /* ... ck_method ........................................................... */
 769
 770 STATIC OP *(*indirect_old_ck_method)(pTHX_ OP *) = 0;
 771
 772 STATIC OP *indirect_ck_method(pTHX_ OP *o) {
 773  if (indirect_hint()) {
 774   OP *op = cUNOPo->op_first;
 775
 776   /* Indirect method call is only possible when the method is a bareword, so
 777    * don't trip up on $obj->$meth. */
 778   if (op && op->op_type == OP_CONST) {
 779    const indirect_op_info_t *oi = indirect_map_fetch(op);
 780    STRLEN pos;
 781    line_t line;
 782    SV *sv;
 783
 784    if (!oi)
 785     goto done;
 786
 787    sv   = sv_2mortal(newSVpvn(oi->buf, oi->len));
 788    pos  = oi->pos;
 789    /* Keep the old line so that we really point to the first line of the
 790     * expression. */
 791    line = oi->line;
 792
 793    o = indirect_old_ck_method(aTHX_ o);
 794    /* o may now be a method_named */
 795
 796    indirect_map_store(o, pos, sv, line);
 797    return o;
 798   }
 799  }
 800
 801 done:
 802  o = indirect_old_ck_method(aTHX_ o);
 803
 804  indirect_map_delete(o);
 805  return o;
 806 }
 807
 808 /* ... ck_method_named ..................................................... */
 809
 810 /* "use foo/no foo" compiles its call to import/unimport directly to a
 811  * method_named op. */
 812
 813 STATIC OP *(*indirect_old_ck_method_named)(pTHX_ OP *) = 0;
 814
 815 STATIC OP *indirect_ck_method_named(pTHX_ OP *o) {
 816  if (indirect_hint()) {
 817   STRLEN pos;
 818   line_t line;
 819   SV *sv;
 820
 821   sv = cSVOPo_sv;
 822   if (!SvPOK(sv) || (SvTYPE(sv) < SVt_PV))
 823    goto done;
 824   sv = sv_mortalcopy(sv);
 825
 826   if (!indirect_find(sv, PL_oldbufptr, &pos))
 827    goto done;
 828   line = CopLINE(&PL_compiling);
 829
 830   o = indirect_old_ck_method_named(aTHX_ o);
 831
 832   indirect_map_store(o, pos, sv, line);
 833   return o;
 834  }
 835
 836 done:
 837  o = indirect_old_ck_method_named(aTHX_ o);
 838
 839  indirect_map_delete(o);
 840  return o;
 841 }
 842
 843 /* ... ck_entersub ......................................................... */
 844
 845 STATIC OP *(*indirect_old_ck_entersub)(pTHX_ OP *) = 0;
 846
 847 STATIC OP *indirect_ck_entersub(pTHX_ OP *o) {
 848  SV *code = indirect_hint();
 849
 850  o = indirect_old_ck_entersub(aTHX_ o);
 851
 852  if (code) {
 853   const indirect_op_info_t *moi, *ooi;
 854   OP     *mop, *oop;
 855   LISTOP *lop;
 856
 857   oop = o;
 858   do {
 859    lop = (LISTOP *) oop;
 860    if (!(lop->op_flags & OPf_KIDS))
 861     goto done;
 862    oop = lop->op_first;
 863   } while (oop->op_type != OP_PUSHMARK);
 864   oop = OP_SIBLING(oop);
 865   mop = lop->op_last;
 866
 867   if (!oop)
 868    goto done;
 869
 870   switch (oop->op_type) {
 871    case OP_CONST:
 872    case OP_RV2SV:
 873    case OP_PADSV:
 874    case OP_SCOPE:
 875    case OP_LEAVE:
 876     break;
 877    default:
 878     goto done;
 879   }
 880
 881   if (mop->op_type == OP_METHOD)
 882    mop = cUNOPx(mop)->op_first;
 883   else if (mop->op_type != OP_METHOD_NAMED)
 884    goto done;
 885
 886   moi = indirect_map_fetch(mop);
 887   if (!moi)
 888    goto done;
 889
 890   ooi = indirect_map_fetch(oop);
 891   if (!ooi)
 892    goto done;
 893
 894   /* When positions are identical, the method and the object must have the
 895    * same name. But it also means that it is an indirect call, as "foo->foo"
 896    * results in different positions. */
 897   if (   moi->line < ooi->line
 898       || (moi->line == ooi->line && moi->pos <= ooi->pos)) {
 899    SV *file;
 900    dSP;
 901
 902    ENTER;
 903    SAVETMPS;
 904
 905 #ifdef USE_ITHREADS
 906    file = sv_2mortal(newSVpv(CopFILE(&PL_compiling), 0));
 907 #else
 908    file = sv_mortalcopy(CopFILESV(&PL_compiling));
 909 #endif
 910
 911    PUSHMARK(SP);
 912    EXTEND(SP, 4);
 913    mPUSHp(ooi->buf, ooi->len);
 914    mPUSHp(moi->buf, moi->len);
 915    PUSHs(file);
 916    mPUSHu(moi->line);
 917    PUTBACK;
 918
 919    call_sv(code, G_VOID);
 920
 921    PUTBACK;
 922
 923    FREETMPS;
 924    LEAVE;
 925   }
 926  }
 927
 928 done:
 929  return o;
 930 }
 931
 932 STATIC U32 indirect_initialized = 0;
 933
 934 STATIC void indirect_teardown(pTHX_ void *root) {
 935  if (!indirect_initialized)
 936   return;
 937
 938 #if I_MULTIPLICITY
 939  if (aTHX != root)
 940   return;
 941 #endif
 942
 943  {
 944   dMY_CXT;
 945   ptable_free(MY_CXT.map);
 946   MY_CXT.map = NULL;
 947 #if I_THREADSAFE
 948   ptable_hints_free(MY_CXT.tbl);
 949   MY_CXT.tbl = NULL;
 950 #endif
 951  }
 952
 953  indirect_ck_restore(OP_CONST,   &indirect_old_ck_const);
 954  indirect_ck_restore(OP_RV2SV,   &indirect_old_ck_rv2sv);
 955  indirect_ck_restore(OP_PADANY,  &indirect_old_ck_padany);
 956  indirect_ck_restore(OP_SCOPE,   &indirect_old_ck_scope);
 957  indirect_ck_restore(OP_LINESEQ, &indirect_old_ck_lineseq);
 958
 959  indirect_ck_restore(OP_METHOD,       &indirect_old_ck_method);
 960  indirect_ck_restore(OP_METHOD_NAMED, &indirect_old_ck_method_named);
 961  indirect_ck_restore(OP_ENTERSUB,     &indirect_old_ck_entersub);
 962
 963  indirect_initialized = 0;
 964 }
 965
 966 STATIC void indirect_setup(pTHX) {
 967 #define indirect_setup() indirect_setup(aTHX)
 968  if (indirect_initialized)
 969   return;
 970
 971  {
 972   MY_CXT_INIT;
 973 #if I_THREADSAFE
 974   MY_CXT.tbl         = ptable_new();
 975   MY_CXT.owner       = aTHX;
 976 #endif
 977   MY_CXT.map         = ptable_new();
 978   MY_CXT.global_code = NULL;
 979  }
 980
 981  indirect_ck_replace(OP_CONST,   indirect_ck_const,  &indirect_old_ck_const);
 982  indirect_ck_replace(OP_RV2SV,   indirect_ck_rv2sv,  &indirect_old_ck_rv2sv);
 983  indirect_ck_replace(OP_PADANY,  indirect_ck_padany, &indirect_old_ck_padany);
 984  indirect_ck_replace(OP_SCOPE,   indirect_ck_scope,  &indirect_old_ck_scope);
 985  indirect_ck_replace(OP_LINESEQ, indirect_ck_scope,  &indirect_old_ck_lineseq);
 986
 987  indirect_ck_replace(OP_METHOD,       indirect_ck_method,
 988                                       &indirect_old_ck_method);
 989  indirect_ck_replace(OP_METHOD_NAMED, indirect_ck_method_named,
 990                                       &indirect_old_ck_method_named);
 991  indirect_ck_replace(OP_ENTERSUB,     indirect_ck_entersub,
 992                                       &indirect_old_ck_entersub);
 993
 994 #if I_MULTIPLICITY
 995  call_atexit(indirect_teardown, aTHX);
 996 #else
 997  call_atexit(indirect_teardown, NULL);
 998 #endif
 999
1000  indirect_initialized = 1;
1001 }
1002
1003 STATIC U32 indirect_booted = 0;
1004
1005 /* --- XS ------------------------------------------------------------------ */
1006
1007 MODULE = indirect      PACKAGE = indirect
1008
1009 PROTOTYPES: ENABLE
1010
1011 BOOT:
1012 {
1013  if (!indirect_booted++) {
1014   HV *stash;
1015
1016   PERL_HASH(indirect_hash, __PACKAGE__, __PACKAGE_LEN__);
1017
1018   stash = gv_stashpvn(__PACKAGE__, __PACKAGE_LEN__, 1);
1019   newCONSTSUB(stash, "I_THREADSAFE", newSVuv(I_THREADSAFE));
1020   newCONSTSUB(stash, "I_FORKSAFE",   newSVuv(I_FORKSAFE));
1021  }
1022
1023  indirect_setup();
1024 }
1025
1026 #if I_THREADSAFE
1027
1028 void
1029 CLONE(...)
1030 PROTOTYPE: DISABLE
1031 PREINIT:
1032  ptable *t;
1033  SV     *global_code_dup;
1034  GV     *gv;
1035 PPCODE:
1036  {
1037   indirect_ptable_clone_ud ud;
1038   dMY_CXT;
1039   t = ptable_new();
1040   indirect_ptable_clone_ud_init(ud, t, MY_CXT.owner);
1041   ptable_walk(MY_CXT.tbl, indirect_ptable_clone, &ud);
1042   global_code_dup = indirect_dup_inc(MY_CXT.global_code, &ud);
1043   indirect_ptable_clone_ud_deinit(ud);
1044  }
1045  {
1046   MY_CXT_CLONE;
1047   MY_CXT.map         = ptable_new();
1048   MY_CXT.tbl         = t;
1049   MY_CXT.owner       = aTHX;
1050   MY_CXT.global_code = global_code_dup;
1051  }
1052  gv = gv_fetchpv(__PACKAGE__ "::_THREAD_CLEANUP", 0, SVt_PVCV);
1053  if (gv) {
1054   CV *cv = GvCV(gv);
1055   if (!PL_endav)
1056    PL_endav = newAV();
1057   SvREFCNT_inc(cv);
1058   if (!av_store(PL_endav, av_len(PL_endav) + 1, (SV *) cv))
1059    SvREFCNT_dec(cv);
1060   sv_magicext((SV *) PL_endav, NULL, PERL_MAGIC_ext, &indirect_endav_vtbl, NULL, 0);
1061  }
1062  XSRETURN(0);
1063
1064 void
1065 _THREAD_CLEANUP(...)
1066 PROTOTYPE: DISABLE
1067 PPCODE:
1068  indirect_thread_cleanup(aTHX_ NULL);
1069  XSRETURN(0);
1070
1071 #endif
1072
1073 SV *
1074 _tag(SV *value)
1075 PROTOTYPE: $
1076 CODE:
1077  RETVAL = indirect_tag(value);
1078 OUTPUT:
1079  RETVAL
1080
1081 void
1082 _global(SV *code)
1083 PROTOTYPE: $
1084 PPCODE:
1085  if (!SvOK(code))
1086   code = NULL;
1087  else if (SvROK(code))
1088   code = SvRV(code);
1089  {
1090   dMY_CXT;
1091   SvREFCNT_dec(MY_CXT.global_code);
1092   MY_CXT.global_code = SvREFCNT_inc(code);
1093  }
1094  XSRETURN(0);