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 OpSIBLING
  67 # ifdef OP_SIBLING
  68 #  define OpSIBLING(O) OP_SIBLING(O)
  69 # else
  70 #  define OpSIBLING(O) ((O)->op_sibling)
  71 # endif
  72 #endif
  73
  74 #define I_HAS_PERL(R, V, S) (PERL_REVISION > (R) || (PERL_REVISION == (R) && (PERL_VERSION > (V) || (PERL_VERSION == (V) && (PERL_SUBVERSION >= (S))))))
  75
  76 #if I_HAS_PERL(5, 10, 0) || defined(PL_parser)
  77 # ifndef PL_linestr
  78 #  define PL_linestr PL_parser->linestr
  79 # endif
  80 # ifndef PL_bufptr
  81 #  define PL_bufptr PL_parser->bufptr
  82 # endif
  83 # ifndef PL_oldbufptr
  84 #  define PL_oldbufptr PL_parser->oldbufptr
  85 # endif
  86 # ifndef PL_lex_inwhat
  87 #  define PL_lex_inwhat PL_parser->lex_inwhat
  88 # endif
  89 #else
  90 # ifndef PL_linestr
  91 #  define PL_linestr PL_Ilinestr
  92 # endif
  93 # ifndef PL_bufptr
  94 #  define PL_bufptr PL_Ibufptr
  95 # endif
  96 # ifndef PL_oldbufptr
  97 #  define PL_oldbufptr PL_Ioldbufptr
  98 # endif
  99 # ifndef PL_lex_inwhat
 100 #  define PL_lex_inwhat PL_Ilex_inwhat
 101 # endif
 102 #endif
 103
 104 #ifndef I_WORKAROUND_REQUIRE_PROPAGATION
 105 # define I_WORKAROUND_REQUIRE_PROPAGATION !I_HAS_PERL(5, 10, 1)
 106 #endif
 107
 108 /* ... Thread safety and multiplicity ...................................... */
 109
 110 /* Safe unless stated otherwise in Makefile.PL */
 111 #ifndef I_FORKSAFE
 112 # define I_FORKSAFE 1
 113 #endif
 114
 115 #ifndef I_MULTIPLICITY
 116 # if defined(MULTIPLICITY)
 117 #  define I_MULTIPLICITY 1
 118 # else
 119 #  define I_MULTIPLICITY 0
 120 # endif
 121 #endif
 122 #if I_MULTIPLICITY
 123 # ifndef PERL_IMPLICIT_CONTEXT
 124 #  error MULTIPLICITY builds must set PERL_IMPLICIT_CONTEXT
 125 # endif
 126 #endif
 127 #if I_MULTIPLICITY && !defined(tTHX)
 128 # define tTHX PerlInterpreter*
 129 #endif
 130
 131 #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))
 132 # define I_THREADSAFE 1
 133 # ifndef MY_CXT_CLONE
 134 #  define MY_CXT_CLONE \
 135     dMY_CXT_SV;                                                      \
 136     my_cxt_t *my_cxtp = (my_cxt_t*)SvPVX(newSV(sizeof(my_cxt_t)-1)); \
 137     Copy(INT2PTR(my_cxt_t*, SvUV(my_cxt_sv)), my_cxtp, 1, my_cxt_t); \
 138     sv_setuv(my_cxt_sv, PTR2UV(my_cxtp))
 139 # endif
 140 #else
 141 # define I_THREADSAFE 0
 142 # undef  dMY_CXT
 143 # define dMY_CXT      dNOOP
 144 # undef  MY_CXT
 145 # define MY_CXT       indirect_globaldata
 146 # undef  START_MY_CXT
 147 # define START_MY_CXT static my_cxt_t MY_CXT;
 148 # undef  MY_CXT_INIT
 149 # define MY_CXT_INIT  NOOP
 150 # undef  MY_CXT_CLONE
 151 # define MY_CXT_CLONE NOOP
 152 #endif
 153
 154 #if defined(OP_CHECK_MUTEX_LOCK) && defined(OP_CHECK_MUTEX_UNLOCK)
 155 # define I_CHECK_MUTEX_LOCK   OP_CHECK_MUTEX_LOCK
 156 # define I_CHECK_MUTEX_UNLOCK OP_CHECK_MUTEX_UNLOCK
 157 #else
 158 # define I_CHECK_MUTEX_LOCK   OP_REFCNT_LOCK
 159 # define I_CHECK_MUTEX_UNLOCK OP_REFCNT_UNLOCK
 160 #endif
 161
 162 typedef OP *(*indirect_ck_t)(pTHX_ OP *);
 163
 164 #ifdef wrap_op_checker
 165
 166 # define indirect_ck_replace(T, NC, OCP) wrap_op_checker((T), (NC), (OCP))
 167
 168 #else
 169
 170 static void indirect_ck_replace(pTHX_ OPCODE type, indirect_ck_t new_ck, indirect_ck_t *old_ck_p) {
 171 #define indirect_ck_replace(T, NC, OCP) indirect_ck_replace(aTHX_ (T), (NC), (OCP))
 172  I_CHECK_MUTEX_LOCK;
 173  if (!*old_ck_p) {
 174   *old_ck_p      = PL_check[type];
 175   PL_check[type] = new_ck;
 176  }
 177  I_CHECK_MUTEX_UNLOCK;
 178 }
 179
 180 #endif
 181
 182 static void indirect_ck_restore(pTHX_ OPCODE type, indirect_ck_t *old_ck_p) {
 183 #define indirect_ck_restore(T, OCP) indirect_ck_restore(aTHX_ (T), (OCP))
 184  I_CHECK_MUTEX_LOCK;
 185  if (*old_ck_p) {
 186   PL_check[type] = *old_ck_p;
 187   *old_ck_p      = 0;
 188  }
 189  I_CHECK_MUTEX_UNLOCK;
 190 }
 191
 192 /* --- Helpers ------------------------------------------------------------- */
 193
 194 /* ... Thread-safe hints ................................................... */
 195
 196 #if I_WORKAROUND_REQUIRE_PROPAGATION
 197
 198 typedef struct {
 199  SV *code;
 200  IV  require_tag;
 201 } indirect_hint_t;
 202
 203 #define I_HINT_STRUCT 1
 204
 205 #define I_HINT_CODE(H) ((H)->code)
 206
 207 #define I_HINT_FREE(H) {   \
 208  indirect_hint_t *h = (H); \
 209  SvREFCNT_dec(h->code);    \
 210  PerlMemShared_free(h);    \
 211 }
 212
 213 #else  /*  I_WORKAROUND_REQUIRE_PROPAGATION */
 214
 215 typedef SV indirect_hint_t;
 216
 217 #define I_HINT_STRUCT 0
 218
 219 #define I_HINT_CODE(H) (H)
 220
 221 #define I_HINT_FREE(H) SvREFCNT_dec(H);
 222
 223 #endif /* !I_WORKAROUND_REQUIRE_PROPAGATION */
 224
 225 #if I_THREADSAFE
 226
 227 #define PTABLE_NAME        ptable_hints
 228 #define PTABLE_VAL_FREE(V) I_HINT_FREE(V)
 229
 230 #define pPTBL  pTHX
 231 #define pPTBL_ pTHX_
 232 #define aPTBL  aTHX
 233 #define aPTBL_ aTHX_
 234
 235 #include "ptable.h"
 236
 237 #define ptable_hints_store(T, K, V) ptable_hints_store(aTHX_ (T), (K), (V))
 238 #define ptable_hints_free(T)        ptable_hints_free(aTHX_ (T))
 239
 240 #endif /* I_THREADSAFE */
 241
 242 /* Define the op->str ptable here because we need to be able to clean it during
 243  * thread cleanup. */
 244
 245 typedef struct {
 246  char   *buf;
 247  STRLEN  pos;
 248  STRLEN  size;
 249  STRLEN  len;
 250  line_t  line;
 251 } indirect_op_info_t;
 252
 253 #define PTABLE_NAME        ptable
 254 #define PTABLE_VAL_FREE(V) if (V) { Safefree(((indirect_op_info_t *) (V))->buf); Safefree(V); }
 255
 256 #define pPTBL  pTHX
 257 #define pPTBL_ pTHX_
 258 #define aPTBL  aTHX
 259 #define aPTBL_ aTHX_
 260
 261 #include "ptable.h"
 262
 263 #define ptable_store(T, K, V) ptable_store(aTHX_ (T), (K), (V))
 264 #define ptable_delete(T, K)   ptable_delete(aTHX_ (T), (K))
 265 #define ptable_clear(T)       ptable_clear(aTHX_ (T))
 266 #define ptable_free(T)        ptable_free(aTHX_ (T))
 267
 268 #define MY_CXT_KEY __PACKAGE__ "::_guts" XS_VERSION
 269
 270 typedef struct {
 271 #if I_THREADSAFE
 272  ptable *tbl; /* It really is a ptable_hints */
 273  tTHX    owner;
 274 #endif
 275  ptable *map;
 276  SV     *global_code;
 277 } my_cxt_t;
 278
 279 START_MY_CXT
 280
 281 #if I_THREADSAFE
 282
 283 typedef struct {
 284  ptable *tbl;
 285 #if I_HAS_PERL(5, 13, 2)
 286  CLONE_PARAMS *params;
 287 #else
 288  CLONE_PARAMS params;
 289 #endif
 290 } indirect_ptable_clone_ud;
 291
 292 #if I_HAS_PERL(5, 13, 2)
 293 # define indirect_ptable_clone_ud_init(U, T, O) \
 294    (U).tbl    = (T); \
 295    (U).params = Perl_clone_params_new((O), aTHX)
 296 # define indirect_ptable_clone_ud_deinit(U) Perl_clone_params_del((U).params)
 297 # define indirect_dup_inc(S, U)             SvREFCNT_inc(sv_dup((S), (U)->params))
 298 #else
 299 # define indirect_ptable_clone_ud_init(U, T, O) \
 300    (U).tbl               = (T);     \
 301    (U).params.stashes    = newAV(); \
 302    (U).params.flags      = 0;       \
 303    (U).params.proto_perl = (O)
 304 # define indirect_ptable_clone_ud_deinit(U) SvREFCNT_dec((U).params.stashes)
 305 # define indirect_dup_inc(S, U)             SvREFCNT_inc(sv_dup((S), &((U)->params)))
 306 #endif
 307
 308 static void indirect_ptable_clone(pTHX_ ptable_ent *ent, void *ud_) {
 309  indirect_ptable_clone_ud *ud = ud_;
 310  indirect_hint_t          *h1 = ent->val;
 311  indirect_hint_t          *h2;
 312
 313 #if I_HINT_STRUCT
 314
 315  h2              = PerlMemShared_malloc(sizeof *h2);
 316  h2->code        = indirect_dup_inc(h1->code, ud);
 317 #if I_WORKAROUND_REQUIRE_PROPAGATION
 318  h2->require_tag = PTR2IV(indirect_dup_inc(INT2PTR(SV *, h1->require_tag), ud));
 319 #endif
 320
 321 #else  /*  I_HINT_STRUCT */
 322
 323  h2 = indirect_dup_inc(h1, ud);
 324
 325 #endif /* !I_HINT_STRUCT */
 326
 327  ptable_hints_store(ud->tbl, ent->key, h2);
 328 }
 329
 330 static void indirect_thread_cleanup(pTHX_ void *ud) {
 331  dMY_CXT;
 332
 333  SvREFCNT_dec(MY_CXT.global_code);
 334  MY_CXT.global_code = NULL;
 335  ptable_free(MY_CXT.map);
 336  MY_CXT.map = NULL;
 337  ptable_hints_free(MY_CXT.tbl);
 338  MY_CXT.tbl = NULL;
 339 }
 340
 341 static int indirect_endav_free(pTHX_ SV *sv, MAGIC *mg) {
 342  SAVEDESTRUCTOR_X(indirect_thread_cleanup, NULL);
 343
 344  return 0;
 345 }
 346
 347 static MGVTBL indirect_endav_vtbl = {
 348  0,
 349  0,
 350  0,
 351  0,
 352  indirect_endav_free
 353 #if MGf_COPY
 354  , 0
 355 #endif
 356 #if MGf_DUP
 357  , 0
 358 #endif
 359 #if MGf_LOCAL
 360  , 0
 361 #endif
 362 };
 363
 364 #endif /* I_THREADSAFE */
 365
 366 #if I_WORKAROUND_REQUIRE_PROPAGATION
 367 static IV indirect_require_tag(pTHX) {
 368 #define indirect_require_tag() indirect_require_tag(aTHX)
 369  const CV *cv, *outside;
 370
 371  cv = PL_compcv;
 372
 373  if (!cv) {
 374   /* If for some reason the pragma is operational at run-time, try to discover
 375    * the current cv in use. */
 376   const PERL_SI *si;
 377
 378   for (si = PL_curstackinfo; si; si = si->si_prev) {
 379    I32 cxix;
 380
 381    for (cxix = si->si_cxix; cxix >= 0; --cxix) {
 382     const PERL_CONTEXT *cx = si->si_cxstack + cxix;
 383
 384     switch (CxTYPE(cx)) {
 385      case CXt_SUB:
 386      case CXt_FORMAT:
 387       /* The propagation workaround is only needed up to 5.10.0 and at that
 388        * time format and sub contexts were still identical. And even later the
 389        * cv members offsets should have been kept the same. */
 390       cv = cx->blk_sub.cv;
 391       goto get_enclosing_cv;
 392      case CXt_EVAL:
 393       cv = cx->blk_eval.cv;
 394       goto get_enclosing_cv;
 395      default:
 396       break;
 397     }
 398    }
 399   }
 400
 401   cv = PL_main_cv;
 402  }
 403
 404 get_enclosing_cv:
 405  for (outside = CvOUTSIDE(cv); outside; outside = CvOUTSIDE(cv))
 406   cv = outside;
 407
 408  return PTR2IV(cv);
 409 }
 410 #endif /* I_WORKAROUND_REQUIRE_PROPAGATION */
 411
 412 static SV *indirect_tag(pTHX_ SV *value) {
 413 #define indirect_tag(V) indirect_tag(aTHX_ (V))
 414  indirect_hint_t *h;
 415  SV              *code = NULL;
 416 #if I_THREADSAFE
 417  dMY_CXT;
 418
 419  if (!MY_CXT.tbl)
 420   return newSViv(0);
 421 #endif /* I_THREADSAFE */
 422
 423  if (SvROK(value)) {
 424   value = SvRV(value);
 425   if (SvTYPE(value) >= SVt_PVCV) {
 426    code = value;
 427    SvREFCNT_inc_simple_void_NN(code);
 428   }
 429  }
 430
 431 #if I_HINT_STRUCT
 432  h = PerlMemShared_malloc(sizeof *h);
 433  h->code        = code;
 434 # if I_WORKAROUND_REQUIRE_PROPAGATION
 435  h->require_tag = indirect_require_tag();
 436 # endif /* I_WORKAROUND_REQUIRE_PROPAGATION */
 437 #else  /*  I_HINT_STRUCT */
 438  h = code;
 439 #endif /* !I_HINT_STRUCT */
 440
 441 #if I_THREADSAFE
 442  /* We only need for the key to be an unique tag for looking up the value later
 443   * Allocated memory provides convenient unique identifiers, so that's why we
 444   * use the hint as the key itself. */
 445  ptable_hints_store(MY_CXT.tbl, h, h);
 446 #endif /* I_THREADSAFE */
 447
 448  return newSViv(PTR2IV(h));
 449 }
 450
 451 static SV *indirect_detag(pTHX_ const SV *hint) {
 452 #define indirect_detag(H) indirect_detag(aTHX_ (H))
 453  indirect_hint_t *h;
 454 #if I_THREADSAFE || I_WORKAROUND_REQUIRE_PROPAGATION
 455  dMY_CXT;
 456 #endif
 457
 458 #if I_THREADSAFE
 459  if (!MY_CXT.tbl)
 460   return NULL;
 461 #endif /* I_THREADSAFE */
 462
 463  h = INT2PTR(indirect_hint_t *, SvIVX(hint));
 464 #if I_THREADSAFE
 465  h = ptable_fetch(MY_CXT.tbl, h);
 466 #endif /* I_THREADSAFE */
 467
 468 #if I_WORKAROUND_REQUIRE_PROPAGATION
 469  if (indirect_require_tag() != h->require_tag)
 470   return MY_CXT.global_code;
 471 #endif /* I_WORKAROUND_REQUIRE_PROPAGATION */
 472
 473  return I_HINT_CODE(h);
 474 }
 475
 476 static VOL U32 indirect_hash = 0;
 477
 478 static SV *indirect_hint(pTHX) {
 479 #define indirect_hint() indirect_hint(aTHX)
 480  SV *hint = NULL;
 481
 482  if (IN_PERL_RUNTIME)
 483   return NULL;
 484
 485 #if I_HAS_PERL(5, 10, 0) || defined(PL_parser)
 486  if (!PL_parser)
 487   return NULL;
 488 #endif
 489
 490 #ifdef cop_hints_fetch_pvn
 491  hint = cop_hints_fetch_pvn(PL_curcop, __PACKAGE__, __PACKAGE_LEN__,
 492                                                               indirect_hash, 0);
 493 #elif I_HAS_PERL(5, 9, 5)
 494  hint = Perl_refcounted_he_fetch(aTHX_ PL_curcop->cop_hints_hash,
 495                                        NULL,
 496                                        __PACKAGE__, __PACKAGE_LEN__,
 497                                        0,
 498                                        indirect_hash);
 499 #else
 500  {
 501   SV **val = hv_fetch(GvHV(PL_hintgv), __PACKAGE__, __PACKAGE_LEN__, 0);
 502   if (val)
 503    hint = *val;
 504  }
 505 #endif
 506
 507  if (hint && SvIOK(hint))
 508   return indirect_detag(hint);
 509  else {
 510   dMY_CXT;
 511   return MY_CXT.global_code;
 512  }
 513 }
 514
 515 /* ... op -> source position ............................................... */
 516
 517 static void indirect_map_store(pTHX_ const OP *o, STRLEN pos, SV *sv, line_t line) {
 518 #define indirect_map_store(O, P, N, L) indirect_map_store(aTHX_ (O), (P), (N), (L))
 519  indirect_op_info_t *oi;
 520  const char *s;
 521  STRLEN len;
 522  dMY_CXT;
 523
 524  /* No need to check for MY_CXT.map != NULL because this code path is always
 525   * guarded by indirect_hint(). */
 526
 527  if (!(oi = ptable_fetch(MY_CXT.map, o))) {
 528   Newx(oi, 1, indirect_op_info_t);
 529   ptable_store(MY_CXT.map, o, oi);
 530   oi->buf  = NULL;
 531   oi->size = 0;
 532  }
 533
 534  if (sv) {
 535   s = SvPV_const(sv, len);
 536  } else {
 537   s   = "{";
 538   len = 1;
 539  }
 540
 541  if (len > oi->size) {
 542   Safefree(oi->buf);
 543   Newx(oi->buf, len, char);
 544   oi->size = len;
 545  }
 546  Copy(s, oi->buf, len, char);
 547
 548  oi->len  = len;
 549  oi->pos  = pos;
 550  oi->line = line;
 551 }
 552
 553 static const indirect_op_info_t *indirect_map_fetch(pTHX_ const OP *o) {
 554 #define indirect_map_fetch(O) indirect_map_fetch(aTHX_ (O))
 555  dMY_CXT;
 556
 557  /* No need to check for MY_CXT.map != NULL because this code path is always
 558   * guarded by indirect_hint(). */
 559
 560  return ptable_fetch(MY_CXT.map, o);
 561 }
 562
 563 static void indirect_map_delete(pTHX_ const OP *o) {
 564 #define indirect_map_delete(O) indirect_map_delete(aTHX_ (O))
 565  dMY_CXT;
 566
 567  if (MY_CXT.map)
 568   ptable_delete(MY_CXT.map, o);
 569 }
 570
 571 /* --- Check functions ----------------------------------------------------- */
 572
 573 static int indirect_find(pTHX_ SV *name_sv, const char *line_bufptr, STRLEN *name_pos) {
 574 #define indirect_find(NSV, LBP, NP) indirect_find(aTHX_ (NSV), (LBP), (NP))
 575  STRLEN      name_len, line_len;
 576  const char *name, *name_end;
 577  const char *line, *line_end;
 578  const char *p;
 579
 580  line     = SvPV_const(PL_linestr, line_len);
 581  line_end = line + line_len;
 582
 583  name = SvPV_const(name_sv, name_len);
 584  if (name_len >= 1 && *name == '$') {
 585   ++name;
 586   --name_len;
 587   while (line_bufptr < line_end && *line_bufptr != '$')
 588    ++line_bufptr;
 589   if (line_bufptr >= line_end)
 590    return 0;
 591  }
 592  name_end = name + name_len;
 593
 594  p = line_bufptr;
 595  while (1) {
 596   p = ninstr(p, line_end, name, name_end);
 597   if (!p)
 598    return 0;
 599   if (!isALNUM(p[name_len]))
 600    break;
 601   /* p points to a word that has name as prefix, skip the rest of the word */
 602   p += name_len + 1;
 603   while (isALNUM(*p))
 604    ++p;
 605  }
 606
 607  *name_pos = p - line;
 608
 609  return 1;
 610 }
 611
 612 /* ... ck_const ............................................................ */
 613
 614 static OP *(*indirect_old_ck_const)(pTHX_ OP *) = 0;
 615
 616 static OP *indirect_ck_const(pTHX_ OP *o) {
 617  o = indirect_old_ck_const(aTHX_ o);
 618
 619  if (indirect_hint()) {
 620   SV *sv = cSVOPo_sv;
 621
 622   if (SvPOK(sv) && (SvTYPE(sv) >= SVt_PV)) {
 623    STRLEN pos;
 624
 625    if (indirect_find(sv, PL_oldbufptr, &pos)) {
 626     STRLEN len;
 627
 628     /* If the constant is equal to the current package name, try to look for
 629      * a "__PACKAGE__" coming before what we got. We only need to check this
 630      * when we already had a match because __PACKAGE__ can only appear in
 631      * direct method calls ("new __PACKAGE__" is a syntax error). */
 632     len = SvCUR(sv);
 633     if (PL_curstash
 634         && len == (STRLEN) HvNAMELEN_get(PL_curstash)
 635         && memcmp(SvPVX(sv), HvNAME_get(PL_curstash), len) == 0) {
 636      STRLEN pos_pkg;
 637      SV    *pkg = sv_newmortal();
 638      sv_setpvn(pkg, "__PACKAGE__", sizeof("__PACKAGE__")-1);
 639
 640      if (indirect_find(pkg, PL_oldbufptr, &pos_pkg) && pos_pkg < pos) {
 641       sv  = pkg;
 642       pos = pos_pkg;
 643      }
 644     }
 645
 646     indirect_map_store(o, pos, sv, CopLINE(&PL_compiling));
 647     return o;
 648    }
 649   }
 650  }
 651
 652  indirect_map_delete(o);
 653  return o;
 654 }
 655
 656 /* ... ck_rv2sv ............................................................ */
 657
 658 static OP *(*indirect_old_ck_rv2sv)(pTHX_ OP *) = 0;
 659
 660 static OP *indirect_ck_rv2sv(pTHX_ OP *o) {
 661  if (indirect_hint()) {
 662   OP *op = cUNOPo->op_first;
 663   SV *sv;
 664   const char *name = NULL;
 665   STRLEN pos, len;
 666   OPCODE type = (OPCODE) op->op_type;
 667
 668   switch (type) {
 669    case OP_GV:
 670    case OP_GVSV: {
 671     GV *gv = cGVOPx_gv(op);
 672     name = GvNAME(gv);
 673     len  = GvNAMELEN(gv);
 674     break;
 675    }
 676    default:
 677     if ((PL_opargs[type] & OA_CLASS_MASK) == OA_SVOP) {
 678      SV *nsv = cSVOPx_sv(op);
 679      if (SvPOK(nsv) && (SvTYPE(nsv) >= SVt_PV))
 680       name = SvPV_const(nsv, len);
 681     }
 682   }
 683   if (!name)
 684    goto done;
 685
 686   sv = sv_2mortal(newSVpvn("$", 1));
 687   sv_catpvn_nomg(sv, name, len);
 688   if (!indirect_find(sv, PL_oldbufptr, &pos)) {
 689    /* If it failed, retry without the current stash */
 690    const char *stash = HvNAME_get(PL_curstash);
 691    STRLEN stashlen = HvNAMELEN_get(PL_curstash);
 692
 693    if ((len < stashlen + 2) || strnNE(name, stash, stashlen)
 694        || name[stashlen] != ':' || name[stashlen+1] != ':') {
 695     /* Failed again ? Try to remove main */
 696     stash = "main";
 697     stashlen = 4;
 698     if ((len < stashlen + 2) || strnNE(name, stash, stashlen)
 699         || name[stashlen] != ':' || name[stashlen+1] != ':')
 700      goto done;
 701    }
 702
 703    sv_setpvn(sv, "$", 1);
 704    stashlen += 2;
 705    sv_catpvn_nomg(sv, name + stashlen, len - stashlen);
 706    if (!indirect_find(sv, PL_oldbufptr, &pos))
 707     goto done;
 708   }
 709
 710   o = indirect_old_ck_rv2sv(aTHX_ o);
 711
 712   indirect_map_store(o, pos, sv, CopLINE(&PL_compiling));
 713   return o;
 714  }
 715
 716 done:
 717  o = indirect_old_ck_rv2sv(aTHX_ o);
 718
 719  indirect_map_delete(o);
 720  return o;
 721 }
 722
 723 /* ... ck_padany ........................................................... */
 724
 725 static OP *(*indirect_old_ck_padany)(pTHX_ OP *) = 0;
 726
 727 static OP *indirect_ck_padany(pTHX_ OP *o) {
 728  o = indirect_old_ck_padany(aTHX_ o);
 729
 730  if (indirect_hint()) {
 731   SV *sv;
 732   const char *s = PL_oldbufptr, *t = PL_bufptr - 1;
 733
 734   while (s < t && isSPACE(*s)) ++s;
 735   if (*s == '$' && ++s <= t) {
 736    while (s < t && isSPACE(*s)) ++s;
 737    while (s < t && isSPACE(*t)) --t;
 738    sv = sv_2mortal(newSVpvn("$", 1));
 739    sv_catpvn_nomg(sv, s, t - s + 1);
 740    indirect_map_store(o, s - SvPVX_const(PL_linestr),
 741                          sv, CopLINE(&PL_compiling));
 742    return o;
 743   }
 744  }
 745
 746  indirect_map_delete(o);
 747  return o;
 748 }
 749
 750 /* ... ck_scope ............................................................ */
 751
 752 static OP *(*indirect_old_ck_scope)  (pTHX_ OP *) = 0;
 753 static OP *(*indirect_old_ck_lineseq)(pTHX_ OP *) = 0;
 754
 755 static OP *indirect_ck_scope(pTHX_ OP *o) {
 756  OP *(*old_ck)(pTHX_ OP *) = 0;
 757
 758  switch (o->op_type) {
 759   case OP_SCOPE:   old_ck = indirect_old_ck_scope;   break;
 760   case OP_LINESEQ: old_ck = indirect_old_ck_lineseq; break;
 761  }
 762  o = old_ck(aTHX_ o);
 763
 764  if (indirect_hint()) {
 765   indirect_map_store(o, PL_oldbufptr - SvPVX_const(PL_linestr),
 766                         NULL, CopLINE(&PL_compiling));
 767   return o;
 768  }
 769
 770  indirect_map_delete(o);
 771  return o;
 772 }
 773
 774 /* We don't need to clean the map entries for leave ops because they can only
 775  * be created by mutating from a lineseq. */
 776
 777 /* ... ck_method ........................................................... */
 778
 779 static OP *(*indirect_old_ck_method)(pTHX_ OP *) = 0;
 780
 781 static OP *indirect_ck_method(pTHX_ OP *o) {
 782  if (indirect_hint()) {
 783   OP *op = cUNOPo->op_first;
 784
 785   /* Indirect method call is only possible when the method is a bareword, so
 786    * don't trip up on $obj->$meth. */
 787   if (op && op->op_type == OP_CONST) {
 788    const indirect_op_info_t *oi = indirect_map_fetch(op);
 789    STRLEN pos;
 790    line_t line;
 791    SV *sv;
 792
 793    if (!oi)
 794     goto done;
 795
 796    sv   = sv_2mortal(newSVpvn(oi->buf, oi->len));
 797    pos  = oi->pos;
 798    /* Keep the old line so that we really point to the first line of the
 799     * expression. */
 800    line = oi->line;
 801
 802    o = indirect_old_ck_method(aTHX_ o);
 803    /* o may now be a method_named */
 804
 805    indirect_map_store(o, pos, sv, line);
 806    return o;
 807   }
 808  }
 809
 810 done:
 811  o = indirect_old_ck_method(aTHX_ o);
 812
 813  indirect_map_delete(o);
 814  return o;
 815 }
 816
 817 /* ... ck_method_named ..................................................... */
 818
 819 /* "use foo/no foo" compiles its call to import/unimport directly to a
 820  * method_named op. */
 821
 822 static OP *(*indirect_old_ck_method_named)(pTHX_ OP *) = 0;
 823
 824 static OP *indirect_ck_method_named(pTHX_ OP *o) {
 825  if (indirect_hint()) {
 826   STRLEN pos;
 827   line_t line;
 828   SV *sv;
 829
 830   sv = cSVOPo_sv;
 831   if (!SvPOK(sv) || (SvTYPE(sv) < SVt_PV))
 832    goto done;
 833   sv = sv_mortalcopy(sv);
 834
 835   if (!indirect_find(sv, PL_oldbufptr, &pos))
 836    goto done;
 837   line = CopLINE(&PL_compiling);
 838
 839   o = indirect_old_ck_method_named(aTHX_ o);
 840
 841   indirect_map_store(o, pos, sv, line);
 842   return o;
 843  }
 844
 845 done:
 846  o = indirect_old_ck_method_named(aTHX_ o);
 847
 848  indirect_map_delete(o);
 849  return o;
 850 }
 851
 852 /* ... ck_entersub ......................................................... */
 853
 854 static OP *(*indirect_old_ck_entersub)(pTHX_ OP *) = 0;
 855
 856 static OP *indirect_ck_entersub(pTHX_ OP *o) {
 857  SV *code = indirect_hint();
 858
 859  o = indirect_old_ck_entersub(aTHX_ o);
 860
 861  if (code) {
 862   const indirect_op_info_t *moi, *ooi;
 863   OP     *mop, *oop;
 864   LISTOP *lop;
 865
 866   oop = o;
 867   do {
 868    lop = (LISTOP *) oop;
 869    if (!(lop->op_flags & OPf_KIDS))
 870     goto done;
 871    oop = lop->op_first;
 872   } while (oop->op_type != OP_PUSHMARK);
 873   oop = OpSIBLING(oop);
 874   mop = lop->op_last;
 875
 876   if (!oop)
 877    goto done;
 878
 879   switch (oop->op_type) {
 880    case OP_CONST:
 881    case OP_RV2SV:
 882    case OP_PADSV:
 883    case OP_SCOPE:
 884    case OP_LEAVE:
 885     break;
 886    default:
 887     goto done;
 888   }
 889
 890   if (mop->op_type == OP_METHOD)
 891    mop = cUNOPx(mop)->op_first;
 892   else if (mop->op_type != OP_METHOD_NAMED)
 893    goto done;
 894
 895   moi = indirect_map_fetch(mop);
 896   if (!moi)
 897    goto done;
 898
 899   ooi = indirect_map_fetch(oop);
 900   if (!ooi)
 901    goto done;
 902
 903   /* When positions are identical, the method and the object must have the
 904    * same name. But it also means that it is an indirect call, as "foo->foo"
 905    * results in different positions. */
 906   if (   moi->line < ooi->line
 907       || (moi->line == ooi->line && moi->pos <= ooi->pos)) {
 908    SV *file;
 909    dSP;
 910
 911    ENTER;
 912    SAVETMPS;
 913
 914 #ifdef USE_ITHREADS
 915    file = sv_2mortal(newSVpv(CopFILE(&PL_compiling), 0));
 916 #else
 917    file = sv_mortalcopy(CopFILESV(&PL_compiling));
 918 #endif
 919
 920    PUSHMARK(SP);
 921    EXTEND(SP, 4);
 922    mPUSHp(ooi->buf, ooi->len);
 923    mPUSHp(moi->buf, moi->len);
 924    PUSHs(file);
 925    mPUSHu(moi->line);
 926    PUTBACK;
 927
 928    call_sv(code, G_VOID);
 929
 930    PUTBACK;
 931
 932    FREETMPS;
 933    LEAVE;
 934   }
 935  }
 936
 937 done:
 938  return o;
 939 }
 940
 941 /* --- Global setup/teardown ------------------------------------------------ */
 942
 943 static VOL U32 indirect_initialized = 0;
 944
 945 static void indirect_global_teardown(pTHX_ void *root) {
 946  if (!indirect_initialized)
 947   return;
 948
 949 #if I_MULTIPLICITY
 950  if (aTHX != root)
 951   return;
 952 #endif
 953
 954  indirect_ck_restore(OP_CONST,   &indirect_old_ck_const);
 955  indirect_ck_restore(OP_RV2SV,   &indirect_old_ck_rv2sv);
 956  indirect_ck_restore(OP_PADANY,  &indirect_old_ck_padany);
 957  indirect_ck_restore(OP_SCOPE,   &indirect_old_ck_scope);
 958  indirect_ck_restore(OP_LINESEQ, &indirect_old_ck_lineseq);
 959
 960  indirect_ck_restore(OP_METHOD,       &indirect_old_ck_method);
 961  indirect_ck_restore(OP_METHOD_NAMED, &indirect_old_ck_method_named);
 962  indirect_ck_restore(OP_ENTERSUB,     &indirect_old_ck_entersub);
 963
 964  indirect_initialized = 0;
 965
 966  return;
 967 }
 968
 969 static void indirect_global_setup(pTHX) {
 970 #define indirect_global_setup() indirect_global_setup(aTHX)
 971  HV *stash;
 972
 973  if (indirect_initialized)
 974   return;
 975
 976  PERL_HASH(indirect_hash, __PACKAGE__, __PACKAGE_LEN__);
 977
 978  stash = gv_stashpvn(__PACKAGE__, __PACKAGE_LEN__, 1);
 979  newCONSTSUB(stash, "I_THREADSAFE", newSVuv(I_THREADSAFE));
 980  newCONSTSUB(stash, "I_FORKSAFE",   newSVuv(I_FORKSAFE));
 981
 982  indirect_ck_replace(OP_CONST,   indirect_ck_const,  &indirect_old_ck_const);
 983  indirect_ck_replace(OP_RV2SV,   indirect_ck_rv2sv,  &indirect_old_ck_rv2sv);
 984  indirect_ck_replace(OP_PADANY,  indirect_ck_padany, &indirect_old_ck_padany);
 985  indirect_ck_replace(OP_SCOPE,   indirect_ck_scope,  &indirect_old_ck_scope);
 986  indirect_ck_replace(OP_LINESEQ, indirect_ck_scope,  &indirect_old_ck_lineseq);
 987
 988  indirect_ck_replace(OP_METHOD,       indirect_ck_method,
 989                                       &indirect_old_ck_method);
 990  indirect_ck_replace(OP_METHOD_NAMED, indirect_ck_method_named,
 991                                       &indirect_old_ck_method_named);
 992  indirect_ck_replace(OP_ENTERSUB,     indirect_ck_entersub,
 993                                       &indirect_old_ck_entersub);
 994
 995 #if I_MULTIPLICITY
 996  call_atexit(indirect_global_teardown, aTHX);
 997 #else
 998  call_atexit(indirect_global_teardown, NULL);
 999 #endif
1000
1001  indirect_initialized = 1;
1002
1003  return;
1004 }
1005
1006 /* --- Interpreter setup/teardown ------------------------------------------ */
1007
1008 static void indirect_local_teardown(pTHX_ void *param) {
1009  dMY_CXT;
1010
1011  ptable_free(MY_CXT.map);
1012  MY_CXT.map = NULL;
1013
1014 #if I_THREADSAFE
1015  ptable_hints_free(MY_CXT.tbl);
1016  MY_CXT.tbl = NULL;
1017 #endif
1018
1019  return;
1020 }
1021
1022 static void indirect_local_setup(pTHX) {
1023 #define indirect_local_setup() indirect_local_setup(aTHX)
1024  MY_CXT_INIT;
1025
1026 #if I_THREADSAFE
1027  MY_CXT.tbl         = ptable_new();
1028  MY_CXT.owner       = aTHX;
1029 #endif
1030
1031  MY_CXT.map         = ptable_new();
1032  MY_CXT.global_code = NULL;
1033
1034  call_atexit(indirect_local_teardown, NULL);
1035
1036  return;
1037 }
1038
1039 /* --- XS ------------------------------------------------------------------ */
1040
1041 MODULE = indirect      PACKAGE = indirect
1042
1043 PROTOTYPES: ENABLE
1044
1045 BOOT:
1046 {
1047  indirect_global_setup();
1048  indirect_local_setup();
1049 }
1050
1051 #if I_THREADSAFE
1052
1053 void
1054 CLONE(...)
1055 PROTOTYPE: DISABLE
1056 PREINIT:
1057  ptable *t;
1058  SV     *global_code_dup;
1059  GV     *gv;
1060 PPCODE:
1061  {
1062   indirect_ptable_clone_ud ud;
1063   dMY_CXT;
1064   t = ptable_new();
1065   indirect_ptable_clone_ud_init(ud, t, MY_CXT.owner);
1066   ptable_walk(MY_CXT.tbl, indirect_ptable_clone, &ud);
1067   global_code_dup = indirect_dup_inc(MY_CXT.global_code, &ud);
1068   indirect_ptable_clone_ud_deinit(ud);
1069  }
1070  {
1071   MY_CXT_CLONE;
1072   MY_CXT.map         = ptable_new();
1073   MY_CXT.tbl         = t;
1074   MY_CXT.owner       = aTHX;
1075   MY_CXT.global_code = global_code_dup;
1076  }
1077  gv = gv_fetchpv(__PACKAGE__ "::_THREAD_CLEANUP", 0, SVt_PVCV);
1078  if (gv) {
1079   CV *cv = GvCV(gv);
1080   if (!PL_endav)
1081    PL_endav = newAV();
1082   SvREFCNT_inc(cv);
1083   if (!av_store(PL_endav, av_len(PL_endav) + 1, (SV *) cv))
1084    SvREFCNT_dec(cv);
1085   sv_magicext((SV *) PL_endav, NULL, PERL_MAGIC_ext, &indirect_endav_vtbl, NULL, 0);
1086  }
1087  XSRETURN(0);
1088
1089 void
1090 _THREAD_CLEANUP(...)
1091 PROTOTYPE: DISABLE
1092 PPCODE:
1093  indirect_thread_cleanup(aTHX_ NULL);
1094  XSRETURN(0);
1095
1096 #endif
1097
1098 SV *
1099 _tag(SV *value)
1100 PROTOTYPE: $
1101 CODE:
1102  RETVAL = indirect_tag(value);
1103 OUTPUT:
1104  RETVAL
1105
1106 void
1107 _global(SV *code)
1108 PROTOTYPE: $
1109 PPCODE:
1110  if (!SvOK(code))
1111   code = NULL;
1112  else if (SvROK(code))
1113   code = SvRV(code);
1114  {
1115   dMY_CXT;
1116   SvREFCNT_dec(MY_CXT.global_code);
1117   MY_CXT.global_code = SvREFCNT_inc(code);
1118  }
1119  XSRETURN(0);