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 I_THREADSAFE
 155 /* We must use preexistent global mutexes or we will never be able to destroy
 156  * them. */
 157 # if I_HAS_PERL(5, 9, 3)
 158 #  define I_LOADED_LOCK   MUTEX_LOCK(&PL_my_ctx_mutex)
 159 #  define I_LOADED_UNLOCK MUTEX_UNLOCK(&PL_my_ctx_mutex)
 160 # else
 161 #  define I_LOADED_LOCK   OP_REFCNT_LOCK
 162 #  define I_LOADED_UNLOCK OP_REFCNT_UNLOCK
 163 # endif
 164 #else
 165 # define I_LOADED_LOCK   NOOP
 166 # define I_LOADED_UNLOCK NOOP
 167 #endif
 168
 169 #if defined(OP_CHECK_MUTEX_LOCK) && defined(OP_CHECK_MUTEX_UNLOCK)
 170 # define I_CHECK_LOCK   OP_CHECK_MUTEX_LOCK
 171 # define I_CHECK_UNLOCK OP_CHECK_MUTEX_UNLOCK
 172 #elif I_HAS_PERL(5, 9, 3)
 173 # define I_CHECK_LOCK   OP_REFCNT_LOCK
 174 # define I_CHECK_UNLOCK OP_REFCNT_UNLOCK
 175 #else
 176 /* Before perl 5.9.3, indirect_ck_*() calls are already protected by the
 177  * I_LOADED mutex, which falls back to the OP_REFCNT mutex. Make sure we don't
 178  * lock it twice. */
 179 # define I_CHECK_LOCK   NOOP
 180 # define I_CHECK_UNLOCK NOOP
 181 #endif
 182
 183 typedef OP *(*indirect_ck_t)(pTHX_ OP *);
 184
 185 #ifdef wrap_op_checker
 186
 187 # define indirect_ck_replace(T, NC, OCP) wrap_op_checker((T), (NC), (OCP))
 188
 189 #else
 190
 191 static void indirect_ck_replace(pTHX_ OPCODE type, indirect_ck_t new_ck, indirect_ck_t *old_ck_p) {
 192 #define indirect_ck_replace(T, NC, OCP) indirect_ck_replace(aTHX_ (T), (NC), (OCP))
 193  I_CHECK_LOCK;
 194  if (!*old_ck_p) {
 195   *old_ck_p      = PL_check[type];
 196   PL_check[type] = new_ck;
 197  }
 198  I_CHECK_UNLOCK;
 199 }
 200
 201 #endif
 202
 203 static void indirect_ck_restore(pTHX_ OPCODE type, indirect_ck_t *old_ck_p) {
 204 #define indirect_ck_restore(T, OCP) indirect_ck_restore(aTHX_ (T), (OCP))
 205  I_CHECK_LOCK;
 206  if (*old_ck_p) {
 207   PL_check[type] = *old_ck_p;
 208   *old_ck_p      = 0;
 209  }
 210  I_CHECK_UNLOCK;
 211 }
 212
 213 /* --- Helpers ------------------------------------------------------------- */
 214
 215 /* ... Check if the module is loaded ....................................... */
 216
 217 static I32 indirect_loaded = 0;
 218
 219 #if I_THREADSAFE
 220
 221 #define PTABLE_NAME        ptable_loaded
 222 #define PTABLE_VAL_FREE(V) NOOP
 223
 224 #include "ptable.h"
 225
 226 #define ptable_loaded_store(T, K, V) ptable_loaded_store(aPTBLMS_ (T), (K), (V))
 227 #define ptable_loaded_delete(T, K)   ptable_loaded_delete(aPTBLMS_ (T), (K))
 228 #define ptable_loaded_free(T)        ptable_loaded_free(aPTBLMS_ (T))
 229
 230 static ptable *indirect_loaded_cxts = NULL;
 231
 232 static int indirect_is_loaded(pTHX_ void *cxt) {
 233 #define indirect_is_loaded(C) indirect_is_loaded(aTHX_ (C))
 234  int res = 0;
 235
 236  I_LOADED_LOCK;
 237  if (indirect_loaded_cxts && ptable_fetch(indirect_loaded_cxts, cxt))
 238   res = 1;
 239  I_LOADED_UNLOCK;
 240
 241  return res;
 242 }
 243
 244 static int indirect_set_loaded_locked(pTHX_ void *cxt) {
 245 #define indirect_set_loaded_locked(C) indirect_set_loaded_locked(aTHX_ (C))
 246  int global_setup = 0;
 247
 248  if (indirect_loaded <= 0) {
 249   assert(indirect_loaded == 0);
 250   assert(!indirect_loaded_cxts);
 251   indirect_loaded_cxts = ptable_new();
 252   global_setup         = 1;
 253  }
 254  ++indirect_loaded;
 255  assert(indirect_loaded_cxts);
 256  ptable_loaded_store(indirect_loaded_cxts, cxt, cxt);
 257
 258  return global_setup;
 259 }
 260
 261 static int indirect_clear_loaded_locked(pTHX_ void *cxt) {
 262 #define indirect_clear_loaded_locked(C) indirect_clear_loaded_locked(aTHX_ (C))
 263  int global_teardown = 0;
 264
 265  if (indirect_loaded > 1) {
 266   assert(indirect_loaded_cxts);
 267   ptable_loaded_delete(indirect_loaded_cxts, cxt);
 268   --indirect_loaded;
 269  } else if (indirect_loaded_cxts) {
 270   assert(indirect_loaded == 1);
 271   ptable_loaded_free(indirect_loaded_cxts);
 272   indirect_loaded_cxts = NULL;
 273   indirect_loaded      = 0;
 274   global_teardown      = 1;
 275  }
 276
 277  return global_teardown;
 278 }
 279
 280 #else
 281
 282 #define indirect_is_loaded(C)           (indirect_loaded > 0)
 283 #define indirect_set_loaded_locked(C)   ((indirect_loaded++ <= 0) ? 1 : 0)
 284 #define indirect_clear_loaded_locked(C) ((--indirect_loaded <= 0) ? 1 : 0)
 285
 286 #endif
 287
 288 /* ... Thread-safe hints ................................................... */
 289
 290 #if I_WORKAROUND_REQUIRE_PROPAGATION
 291
 292 typedef struct {
 293  SV *code;
 294  IV  require_tag;
 295 } indirect_hint_t;
 296
 297 #define I_HINT_STRUCT 1
 298
 299 #define I_HINT_CODE(H) ((H)->code)
 300
 301 #define I_HINT_FREE(H) {   \
 302  indirect_hint_t *h = (H); \
 303  SvREFCNT_dec(h->code);    \
 304  PerlMemShared_free(h);    \
 305 }
 306
 307 #else  /*  I_WORKAROUND_REQUIRE_PROPAGATION */
 308
 309 typedef SV indirect_hint_t;
 310
 311 #define I_HINT_STRUCT 0
 312
 313 #define I_HINT_CODE(H) (H)
 314
 315 #define I_HINT_FREE(H) SvREFCNT_dec(H);
 316
 317 #endif /* !I_WORKAROUND_REQUIRE_PROPAGATION */
 318
 319 #if I_THREADSAFE
 320
 321 #define PTABLE_NAME        ptable_hints
 322 #define PTABLE_VAL_FREE(V) I_HINT_FREE(V)
 323
 324 #define pPTBL  pTHX
 325 #define pPTBL_ pTHX_
 326 #define aPTBL  aTHX
 327 #define aPTBL_ aTHX_
 328
 329 #include "ptable.h"
 330
 331 #define ptable_hints_store(T, K, V) ptable_hints_store(aTHX_ (T), (K), (V))
 332 #define ptable_hints_free(T)        ptable_hints_free(aTHX_ (T))
 333
 334 #endif /* I_THREADSAFE */
 335
 336 /* Define the op->str ptable here because we need to be able to clean it during
 337  * thread cleanup. */
 338
 339 typedef struct {
 340  char   *buf;
 341  STRLEN  pos;
 342  STRLEN  size;
 343  STRLEN  len;
 344  line_t  line;
 345 } indirect_op_info_t;
 346
 347 #define PTABLE_NAME        ptable
 348 #define PTABLE_VAL_FREE(V) if (V) { Safefree(((indirect_op_info_t *) (V))->buf); Safefree(V); }
 349
 350 #define pPTBL  pTHX
 351 #define pPTBL_ pTHX_
 352 #define aPTBL  aTHX
 353 #define aPTBL_ aTHX_
 354
 355 #include "ptable.h"
 356
 357 #define ptable_store(T, K, V) ptable_store(aTHX_ (T), (K), (V))
 358 #define ptable_delete(T, K)   ptable_delete(aTHX_ (T), (K))
 359 #define ptable_clear(T)       ptable_clear(aTHX_ (T))
 360 #define ptable_free(T)        ptable_free(aTHX_ (T))
 361
 362 #define MY_CXT_KEY __PACKAGE__ "::_guts" XS_VERSION
 363
 364 typedef struct {
 365 #if I_THREADSAFE
 366  ptable *tbl; /* It really is a ptable_hints */
 367  tTHX    owner;
 368 #endif
 369  ptable *map;
 370  SV     *global_code;
 371 } my_cxt_t;
 372
 373 START_MY_CXT
 374
 375 #if I_THREADSAFE
 376
 377 typedef struct {
 378  ptable *tbl;
 379 #if I_HAS_PERL(5, 13, 2)
 380  CLONE_PARAMS *params;
 381 #else
 382  CLONE_PARAMS params;
 383 #endif
 384 } indirect_ptable_clone_ud;
 385
 386 #if I_HAS_PERL(5, 13, 2)
 387 # define indirect_ptable_clone_ud_init(U, T, O) \
 388    (U).tbl    = (T); \
 389    (U).params = Perl_clone_params_new((O), aTHX)
 390 # define indirect_ptable_clone_ud_deinit(U) Perl_clone_params_del((U).params)
 391 # define indirect_dup_inc(S, U)             SvREFCNT_inc(sv_dup((S), (U)->params))
 392 #else
 393 # define indirect_ptable_clone_ud_init(U, T, O) \
 394    (U).tbl               = (T);     \
 395    (U).params.stashes    = newAV(); \
 396    (U).params.flags      = 0;       \
 397    (U).params.proto_perl = (O)
 398 # define indirect_ptable_clone_ud_deinit(U) SvREFCNT_dec((U).params.stashes)
 399 # define indirect_dup_inc(S, U)             SvREFCNT_inc(sv_dup((S), &((U)->params)))
 400 #endif
 401
 402 static void indirect_ptable_clone(pTHX_ ptable_ent *ent, void *ud_) {
 403  indirect_ptable_clone_ud *ud = ud_;
 404  indirect_hint_t          *h1 = ent->val;
 405  indirect_hint_t          *h2;
 406
 407 #if I_HINT_STRUCT
 408
 409  h2              = PerlMemShared_malloc(sizeof *h2);
 410  h2->code        = indirect_dup_inc(h1->code, ud);
 411 #if I_WORKAROUND_REQUIRE_PROPAGATION
 412  h2->require_tag = PTR2IV(indirect_dup_inc(INT2PTR(SV *, h1->require_tag), ud));
 413 #endif
 414
 415 #else  /*  I_HINT_STRUCT */
 416
 417  h2 = indirect_dup_inc(h1, ud);
 418
 419 #endif /* !I_HINT_STRUCT */
 420
 421  ptable_hints_store(ud->tbl, ent->key, h2);
 422 }
 423
 424 static void indirect_thread_cleanup(pTHX_ void *ud) {
 425  int global_teardown;
 426  dMY_CXT;
 427
 428  global_teardown = indirect_clear_loaded_locked(&MY_CXT);
 429  assert(!global_teardown);
 430
 431  SvREFCNT_dec(MY_CXT.global_code);
 432  MY_CXT.global_code = NULL;
 433
 434  ptable_free(MY_CXT.map);
 435  MY_CXT.map = NULL;
 436
 437  ptable_hints_free(MY_CXT.tbl);
 438  MY_CXT.tbl = NULL;
 439 }
 440
 441 static int indirect_endav_free(pTHX_ SV *sv, MAGIC *mg) {
 442  SAVEDESTRUCTOR_X(indirect_thread_cleanup, NULL);
 443
 444  return 0;
 445 }
 446
 447 static MGVTBL indirect_endav_vtbl = {
 448  0,
 449  0,
 450  0,
 451  0,
 452  indirect_endav_free
 453 #if MGf_COPY
 454  , 0
 455 #endif
 456 #if MGf_DUP
 457  , 0
 458 #endif
 459 #if MGf_LOCAL
 460  , 0
 461 #endif
 462 };
 463
 464 #endif /* I_THREADSAFE */
 465
 466 #if I_WORKAROUND_REQUIRE_PROPAGATION
 467 static IV indirect_require_tag(pTHX) {
 468 #define indirect_require_tag() indirect_require_tag(aTHX)
 469  const CV *cv, *outside;
 470
 471  cv = PL_compcv;
 472
 473  if (!cv) {
 474   /* If for some reason the pragma is operational at run-time, try to discover
 475    * the current cv in use. */
 476   const PERL_SI *si;
 477
 478   for (si = PL_curstackinfo; si; si = si->si_prev) {
 479    I32 cxix;
 480
 481    for (cxix = si->si_cxix; cxix >= 0; --cxix) {
 482     const PERL_CONTEXT *cx = si->si_cxstack + cxix;
 483
 484     switch (CxTYPE(cx)) {
 485      case CXt_SUB:
 486      case CXt_FORMAT:
 487       /* The propagation workaround is only needed up to 5.10.0 and at that
 488        * time format and sub contexts were still identical. And even later the
 489        * cv members offsets should have been kept the same. */
 490       cv = cx->blk_sub.cv;
 491       goto get_enclosing_cv;
 492      case CXt_EVAL:
 493       cv = cx->blk_eval.cv;
 494       goto get_enclosing_cv;
 495      default:
 496       break;
 497     }
 498    }
 499   }
 500
 501   cv = PL_main_cv;
 502  }
 503
 504 get_enclosing_cv:
 505  for (outside = CvOUTSIDE(cv); outside; outside = CvOUTSIDE(cv))
 506   cv = outside;
 507
 508  return PTR2IV(cv);
 509 }
 510 #endif /* I_WORKAROUND_REQUIRE_PROPAGATION */
 511
 512 static SV *indirect_tag(pTHX_ SV *value) {
 513 #define indirect_tag(V) indirect_tag(aTHX_ (V))
 514  indirect_hint_t *h;
 515  SV              *code = NULL;
 516 #if I_THREADSAFE
 517  dMY_CXT;
 518
 519  if (!MY_CXT.tbl)
 520   return newSViv(0);
 521 #endif /* I_THREADSAFE */
 522
 523  if (SvROK(value)) {
 524   value = SvRV(value);
 525   if (SvTYPE(value) >= SVt_PVCV) {
 526    code = value;
 527    SvREFCNT_inc_simple_void_NN(code);
 528   }
 529  }
 530
 531 #if I_HINT_STRUCT
 532  h = PerlMemShared_malloc(sizeof *h);
 533  h->code        = code;
 534 # if I_WORKAROUND_REQUIRE_PROPAGATION
 535  h->require_tag = indirect_require_tag();
 536 # endif /* I_WORKAROUND_REQUIRE_PROPAGATION */
 537 #else  /*  I_HINT_STRUCT */
 538  h = code;
 539 #endif /* !I_HINT_STRUCT */
 540
 541 #if I_THREADSAFE
 542  /* We only need for the key to be an unique tag for looking up the value later
 543   * Allocated memory provides convenient unique identifiers, so that's why we
 544   * use the hint as the key itself. */
 545  ptable_hints_store(MY_CXT.tbl, h, h);
 546 #endif /* I_THREADSAFE */
 547
 548  return newSViv(PTR2IV(h));
 549 }
 550
 551 static SV *indirect_detag(pTHX_ const SV *hint) {
 552 #define indirect_detag(H) indirect_detag(aTHX_ (H))
 553  indirect_hint_t *h;
 554 #if I_THREADSAFE || I_WORKAROUND_REQUIRE_PROPAGATION
 555  dMY_CXT;
 556 #endif
 557
 558 #if I_THREADSAFE
 559  if (!MY_CXT.tbl)
 560   return NULL;
 561 #endif /* I_THREADSAFE */
 562
 563  h = INT2PTR(indirect_hint_t *, SvIVX(hint));
 564 #if I_THREADSAFE
 565  h = ptable_fetch(MY_CXT.tbl, h);
 566 #endif /* I_THREADSAFE */
 567
 568 #if I_WORKAROUND_REQUIRE_PROPAGATION
 569  if (indirect_require_tag() != h->require_tag)
 570   return MY_CXT.global_code;
 571 #endif /* I_WORKAROUND_REQUIRE_PROPAGATION */
 572
 573  return I_HINT_CODE(h);
 574 }
 575
 576 static VOL U32 indirect_hash = 0;
 577
 578 static SV *indirect_hint(pTHX) {
 579 #define indirect_hint() indirect_hint(aTHX)
 580  SV *hint = NULL;
 581
 582  if (IN_PERL_RUNTIME)
 583   return NULL;
 584
 585 #if I_HAS_PERL(5, 10, 0) || defined(PL_parser)
 586  if (!PL_parser)
 587   return NULL;
 588 #endif
 589
 590 #ifdef cop_hints_fetch_pvn
 591  hint = cop_hints_fetch_pvn(PL_curcop, __PACKAGE__, __PACKAGE_LEN__,
 592                                                               indirect_hash, 0);
 593 #elif I_HAS_PERL(5, 9, 5)
 594  hint = Perl_refcounted_he_fetch(aTHX_ PL_curcop->cop_hints_hash,
 595                                        NULL,
 596                                        __PACKAGE__, __PACKAGE_LEN__,
 597                                        0,
 598                                        indirect_hash);
 599 #else
 600  {
 601   SV **val = hv_fetch(GvHV(PL_hintgv), __PACKAGE__, __PACKAGE_LEN__, 0);
 602   if (val)
 603    hint = *val;
 604  }
 605 #endif
 606
 607  if (hint && SvIOK(hint)) {
 608   return indirect_detag(hint);
 609  } else {
 610   dMY_CXT;
 611   if (indirect_is_loaded(&MY_CXT))
 612    return MY_CXT.global_code;
 613   else
 614    return NULL;
 615  }
 616 }
 617
 618 /* ... op -> source position ............................................... */
 619
 620 static void indirect_map_store(pTHX_ const OP *o, STRLEN pos, SV *sv, line_t line) {
 621 #define indirect_map_store(O, P, N, L) indirect_map_store(aTHX_ (O), (P), (N), (L))
 622  indirect_op_info_t *oi;
 623  const char *s;
 624  STRLEN len;
 625  dMY_CXT;
 626
 627  /* No need to check for MY_CXT.map != NULL because this code path is always
 628   * guarded by indirect_hint(). */
 629
 630  if (!(oi = ptable_fetch(MY_CXT.map, o))) {
 631   Newx(oi, 1, indirect_op_info_t);
 632   ptable_store(MY_CXT.map, o, oi);
 633   oi->buf  = NULL;
 634   oi->size = 0;
 635  }
 636
 637  if (sv) {
 638   s = SvPV_const(sv, len);
 639  } else {
 640   s   = "{";
 641   len = 1;
 642  }
 643
 644  if (len > oi->size) {
 645   Safefree(oi->buf);
 646   Newx(oi->buf, len, char);
 647   oi->size = len;
 648  }
 649  Copy(s, oi->buf, len, char);
 650
 651  oi->len  = len;
 652  oi->pos  = pos;
 653  oi->line = line;
 654 }
 655
 656 static const indirect_op_info_t *indirect_map_fetch(pTHX_ const OP *o) {
 657 #define indirect_map_fetch(O) indirect_map_fetch(aTHX_ (O))
 658  dMY_CXT;
 659
 660  /* No need to check for MY_CXT.map != NULL because this code path is always
 661   * guarded by indirect_hint(). */
 662
 663  return ptable_fetch(MY_CXT.map, o);
 664 }
 665
 666 static void indirect_map_delete(pTHX_ const OP *o) {
 667 #define indirect_map_delete(O) indirect_map_delete(aTHX_ (O))
 668  dMY_CXT;
 669
 670  if (indirect_is_loaded(&MY_CXT) && MY_CXT.map)
 671   ptable_delete(MY_CXT.map, o);
 672 }
 673
 674 /* --- Check functions ----------------------------------------------------- */
 675
 676 static int indirect_find(pTHX_ SV *name_sv, const char *line_bufptr, STRLEN *name_pos) {
 677 #define indirect_find(NSV, LBP, NP) indirect_find(aTHX_ (NSV), (LBP), (NP))
 678  STRLEN      name_len, line_len;
 679  const char *name, *name_end;
 680  const char *line, *line_end;
 681  const char *p;
 682
 683  line     = SvPV_const(PL_linestr, line_len);
 684  line_end = line + line_len;
 685
 686  name = SvPV_const(name_sv, name_len);
 687  if (name_len >= 1 && *name == '$') {
 688   ++name;
 689   --name_len;
 690   while (line_bufptr < line_end && *line_bufptr != '$')
 691    ++line_bufptr;
 692   if (line_bufptr >= line_end)
 693    return 0;
 694  }
 695  name_end = name + name_len;
 696
 697  p = line_bufptr;
 698  while (1) {
 699   p = ninstr(p, line_end, name, name_end);
 700   if (!p)
 701    return 0;
 702   if (!isALNUM(p[name_len]))
 703    break;
 704   /* p points to a word that has name as prefix, skip the rest of the word */
 705   p += name_len + 1;
 706   while (isALNUM(*p))
 707    ++p;
 708  }
 709
 710  *name_pos = p - line;
 711
 712  return 1;
 713 }
 714
 715 /* ... ck_const ............................................................ */
 716
 717 static OP *(*indirect_old_ck_const)(pTHX_ OP *) = 0;
 718
 719 static OP *indirect_ck_const(pTHX_ OP *o) {
 720  o = indirect_old_ck_const(aTHX_ o);
 721
 722  if (indirect_hint()) {
 723   SV *sv = cSVOPo_sv;
 724
 725   if (SvPOK(sv) && (SvTYPE(sv) >= SVt_PV)) {
 726    STRLEN pos;
 727
 728    if (indirect_find(sv, PL_oldbufptr, &pos)) {
 729     STRLEN len;
 730
 731     /* If the constant is equal to the current package name, try to look for
 732      * a "__PACKAGE__" coming before what we got. We only need to check this
 733      * when we already had a match because __PACKAGE__ can only appear in
 734      * direct method calls ("new __PACKAGE__" is a syntax error). */
 735     len = SvCUR(sv);
 736     if (PL_curstash
 737         && len == (STRLEN) HvNAMELEN_get(PL_curstash)
 738         && memcmp(SvPVX(sv), HvNAME_get(PL_curstash), len) == 0) {
 739      STRLEN pos_pkg;
 740      SV    *pkg = sv_newmortal();
 741      sv_setpvn(pkg, "__PACKAGE__", sizeof("__PACKAGE__")-1);
 742
 743      if (indirect_find(pkg, PL_oldbufptr, &pos_pkg) && pos_pkg < pos) {
 744       sv  = pkg;
 745       pos = pos_pkg;
 746      }
 747     }
 748
 749     indirect_map_store(o, pos, sv, CopLINE(&PL_compiling));
 750     return o;
 751    }
 752   }
 753  }
 754
 755  indirect_map_delete(o);
 756  return o;
 757 }
 758
 759 /* ... ck_rv2sv ............................................................ */
 760
 761 static OP *(*indirect_old_ck_rv2sv)(pTHX_ OP *) = 0;
 762
 763 static OP *indirect_ck_rv2sv(pTHX_ OP *o) {
 764  if (indirect_hint()) {
 765   OP *op = cUNOPo->op_first;
 766   SV *sv;
 767   const char *name = NULL;
 768   STRLEN pos, len;
 769   OPCODE type = (OPCODE) op->op_type;
 770
 771   switch (type) {
 772    case OP_GV:
 773    case OP_GVSV: {
 774     GV *gv = cGVOPx_gv(op);
 775     name = GvNAME(gv);
 776     len  = GvNAMELEN(gv);
 777     break;
 778    }
 779    default:
 780     if ((PL_opargs[type] & OA_CLASS_MASK) == OA_SVOP) {
 781      SV *nsv = cSVOPx_sv(op);
 782      if (SvPOK(nsv) && (SvTYPE(nsv) >= SVt_PV))
 783       name = SvPV_const(nsv, len);
 784     }
 785   }
 786   if (!name)
 787    goto done;
 788
 789   sv = sv_2mortal(newSVpvn("$", 1));
 790   sv_catpvn_nomg(sv, name, len);
 791   if (!indirect_find(sv, PL_oldbufptr, &pos)) {
 792    /* If it failed, retry without the current stash */
 793    const char *stash = HvNAME_get(PL_curstash);
 794    STRLEN stashlen = HvNAMELEN_get(PL_curstash);
 795
 796    if ((len < stashlen + 2) || strnNE(name, stash, stashlen)
 797        || name[stashlen] != ':' || name[stashlen+1] != ':') {
 798     /* Failed again ? Try to remove main */
 799     stash = "main";
 800     stashlen = 4;
 801     if ((len < stashlen + 2) || strnNE(name, stash, stashlen)
 802         || name[stashlen] != ':' || name[stashlen+1] != ':')
 803      goto done;
 804    }
 805
 806    sv_setpvn(sv, "$", 1);
 807    stashlen += 2;
 808    sv_catpvn_nomg(sv, name + stashlen, len - stashlen);
 809    if (!indirect_find(sv, PL_oldbufptr, &pos))
 810     goto done;
 811   }
 812
 813   o = indirect_old_ck_rv2sv(aTHX_ o);
 814
 815   indirect_map_store(o, pos, sv, CopLINE(&PL_compiling));
 816   return o;
 817  }
 818
 819 done:
 820  o = indirect_old_ck_rv2sv(aTHX_ o);
 821
 822  indirect_map_delete(o);
 823  return o;
 824 }
 825
 826 /* ... ck_padany ........................................................... */
 827
 828 static OP *(*indirect_old_ck_padany)(pTHX_ OP *) = 0;
 829
 830 static OP *indirect_ck_padany(pTHX_ OP *o) {
 831  o = indirect_old_ck_padany(aTHX_ o);
 832
 833  if (indirect_hint()) {
 834   SV *sv;
 835   const char *s = PL_oldbufptr, *t = PL_bufptr - 1;
 836
 837   while (s < t && isSPACE(*s)) ++s;
 838   if (*s == '$' && ++s <= t) {
 839    while (s < t && isSPACE(*s)) ++s;
 840    while (s < t && isSPACE(*t)) --t;
 841    sv = sv_2mortal(newSVpvn("$", 1));
 842    sv_catpvn_nomg(sv, s, t - s + 1);
 843    indirect_map_store(o, s - SvPVX_const(PL_linestr),
 844                          sv, CopLINE(&PL_compiling));
 845    return o;
 846   }
 847  }
 848
 849  indirect_map_delete(o);
 850  return o;
 851 }
 852
 853 /* ... ck_scope ............................................................ */
 854
 855 static OP *(*indirect_old_ck_scope)  (pTHX_ OP *) = 0;
 856 static OP *(*indirect_old_ck_lineseq)(pTHX_ OP *) = 0;
 857
 858 static OP *indirect_ck_scope(pTHX_ OP *o) {
 859  OP *(*old_ck)(pTHX_ OP *) = 0;
 860
 861  switch (o->op_type) {
 862   case OP_SCOPE:   old_ck = indirect_old_ck_scope;   break;
 863   case OP_LINESEQ: old_ck = indirect_old_ck_lineseq; break;
 864  }
 865  o = old_ck(aTHX_ o);
 866
 867  if (indirect_hint()) {
 868   indirect_map_store(o, PL_oldbufptr - SvPVX_const(PL_linestr),
 869                         NULL, CopLINE(&PL_compiling));
 870   return o;
 871  }
 872
 873  indirect_map_delete(o);
 874  return o;
 875 }
 876
 877 /* We don't need to clean the map entries for leave ops because they can only
 878  * be created by mutating from a lineseq. */
 879
 880 /* ... ck_method ........................................................... */
 881
 882 static OP *(*indirect_old_ck_method)(pTHX_ OP *) = 0;
 883
 884 static OP *indirect_ck_method(pTHX_ OP *o) {
 885  if (indirect_hint()) {
 886   OP *op = cUNOPo->op_first;
 887
 888   /* Indirect method call is only possible when the method is a bareword, so
 889    * don't trip up on $obj->$meth. */
 890   if (op && op->op_type == OP_CONST) {
 891    const indirect_op_info_t *oi = indirect_map_fetch(op);
 892    STRLEN pos;
 893    line_t line;
 894    SV *sv;
 895
 896    if (!oi)
 897     goto done;
 898
 899    sv   = sv_2mortal(newSVpvn(oi->buf, oi->len));
 900    pos  = oi->pos;
 901    /* Keep the old line so that we really point to the first line of the
 902     * expression. */
 903    line = oi->line;
 904
 905    o = indirect_old_ck_method(aTHX_ o);
 906    /* o may now be a method_named */
 907
 908    indirect_map_store(o, pos, sv, line);
 909    return o;
 910   }
 911  }
 912
 913 done:
 914  o = indirect_old_ck_method(aTHX_ o);
 915
 916  indirect_map_delete(o);
 917  return o;
 918 }
 919
 920 /* ... ck_method_named ..................................................... */
 921
 922 /* "use foo/no foo" compiles its call to import/unimport directly to a
 923  * method_named op. */
 924
 925 static OP *(*indirect_old_ck_method_named)(pTHX_ OP *) = 0;
 926
 927 static OP *indirect_ck_method_named(pTHX_ OP *o) {
 928  if (indirect_hint()) {
 929   STRLEN pos;
 930   line_t line;
 931   SV *sv;
 932
 933   sv = cSVOPo_sv;
 934   if (!SvPOK(sv) || (SvTYPE(sv) < SVt_PV))
 935    goto done;
 936   sv = sv_mortalcopy(sv);
 937
 938   if (!indirect_find(sv, PL_oldbufptr, &pos))
 939    goto done;
 940   line = CopLINE(&PL_compiling);
 941
 942   o = indirect_old_ck_method_named(aTHX_ o);
 943
 944   indirect_map_store(o, pos, sv, line);
 945   return o;
 946  }
 947
 948 done:
 949  o = indirect_old_ck_method_named(aTHX_ o);
 950
 951  indirect_map_delete(o);
 952  return o;
 953 }
 954
 955 /* ... ck_entersub ......................................................... */
 956
 957 static OP *(*indirect_old_ck_entersub)(pTHX_ OP *) = 0;
 958
 959 static OP *indirect_ck_entersub(pTHX_ OP *o) {
 960  SV *code = indirect_hint();
 961
 962  o = indirect_old_ck_entersub(aTHX_ o);
 963
 964  if (code) {
 965   const indirect_op_info_t *moi, *ooi;
 966   OP     *mop, *oop;
 967   LISTOP *lop;
 968
 969   oop = o;
 970   do {
 971    lop = (LISTOP *) oop;
 972    if (!(lop->op_flags & OPf_KIDS))
 973     goto done;
 974    oop = lop->op_first;
 975   } while (oop->op_type != OP_PUSHMARK);
 976   oop = OpSIBLING(oop);
 977   mop = lop->op_last;
 978
 979   if (!oop)
 980    goto done;
 981
 982   switch (oop->op_type) {
 983    case OP_CONST:
 984    case OP_RV2SV:
 985    case OP_PADSV:
 986    case OP_SCOPE:
 987    case OP_LEAVE:
 988     break;
 989    default:
 990     goto done;
 991   }
 992
 993   if (mop->op_type == OP_METHOD)
 994    mop = cUNOPx(mop)->op_first;
 995   else if (mop->op_type != OP_METHOD_NAMED)
 996    goto done;
 997
 998   moi = indirect_map_fetch(mop);
 999   if (!moi)
1000    goto done;
1001
1002   ooi = indirect_map_fetch(oop);
1003   if (!ooi)
1004    goto done;
1005
1006   /* When positions are identical, the method and the object must have the
1007    * same name. But it also means that it is an indirect call, as "foo->foo"
1008    * results in different positions. */
1009   if (   moi->line < ooi->line
1010       || (moi->line == ooi->line && moi->pos <= ooi->pos)) {
1011    SV *file;
1012    dSP;
1013
1014    ENTER;
1015    SAVETMPS;
1016
1017 #ifdef USE_ITHREADS
1018    file = sv_2mortal(newSVpv(CopFILE(&PL_compiling), 0));
1019 #else
1020    file = sv_mortalcopy(CopFILESV(&PL_compiling));
1021 #endif
1022
1023    PUSHMARK(SP);
1024    EXTEND(SP, 4);
1025    mPUSHp(ooi->buf, ooi->len);
1026    mPUSHp(moi->buf, moi->len);
1027    PUSHs(file);
1028    mPUSHu(moi->line);
1029    PUTBACK;
1030
1031    call_sv(code, G_VOID);
1032
1033    PUTBACK;
1034
1035    FREETMPS;
1036    LEAVE;
1037   }
1038  }
1039
1040 done:
1041  return o;
1042 }
1043
1044 /* --- Module setup/teardown ----------------------------------------------- */
1045
1046 static void indirect_teardown(pTHX_ void *interp) {
1047  dMY_CXT;
1048
1049 #if I_MULTIPLICITY
1050  if (aTHX != interp)
1051   return;
1052 #endif
1053
1054  I_LOADED_LOCK;
1055
1056  if (indirect_clear_loaded_locked(&MY_CXT)) {
1057   indirect_ck_restore(OP_CONST,   &indirect_old_ck_const);
1058   indirect_ck_restore(OP_RV2SV,   &indirect_old_ck_rv2sv);
1059   indirect_ck_restore(OP_PADANY,  &indirect_old_ck_padany);
1060   indirect_ck_restore(OP_SCOPE,   &indirect_old_ck_scope);
1061   indirect_ck_restore(OP_LINESEQ, &indirect_old_ck_lineseq);
1062
1063   indirect_ck_restore(OP_METHOD,       &indirect_old_ck_method);
1064   indirect_ck_restore(OP_METHOD_NAMED, &indirect_old_ck_method_named);
1065   indirect_ck_restore(OP_ENTERSUB,     &indirect_old_ck_entersub);
1066  }
1067
1068  I_LOADED_UNLOCK;
1069
1070  SvREFCNT_dec(MY_CXT.global_code);
1071  MY_CXT.global_code = NULL;
1072
1073  ptable_free(MY_CXT.map);
1074  MY_CXT.map = NULL;
1075
1076 #if I_THREADSAFE
1077  ptable_hints_free(MY_CXT.tbl);
1078  MY_CXT.tbl = NULL;
1079 #endif
1080
1081  return;
1082 }
1083
1084 static void indirect_setup(pTHX) {
1085 #define indirect_setup() indirect_setup(aTHX)
1086  MY_CXT_INIT; /* Takes/release PL_my_ctx_mutex */
1087
1088  I_LOADED_LOCK;
1089
1090  if (indirect_set_loaded_locked(&MY_CXT)) {
1091   PERL_HASH(indirect_hash, __PACKAGE__, __PACKAGE_LEN__);
1092
1093   indirect_ck_replace(OP_CONST,   indirect_ck_const,  &indirect_old_ck_const);
1094   indirect_ck_replace(OP_RV2SV,   indirect_ck_rv2sv,  &indirect_old_ck_rv2sv);
1095   indirect_ck_replace(OP_PADANY,  indirect_ck_padany, &indirect_old_ck_padany);
1096   indirect_ck_replace(OP_SCOPE,   indirect_ck_scope,  &indirect_old_ck_scope);
1097   indirect_ck_replace(OP_LINESEQ, indirect_ck_scope,  &indirect_old_ck_lineseq);
1098
1099   indirect_ck_replace(OP_METHOD,       indirect_ck_method,
1100                                        &indirect_old_ck_method);
1101   indirect_ck_replace(OP_METHOD_NAMED, indirect_ck_method_named,
1102                                        &indirect_old_ck_method_named);
1103   indirect_ck_replace(OP_ENTERSUB,     indirect_ck_entersub,
1104                                        &indirect_old_ck_entersub);
1105  }
1106
1107  I_LOADED_UNLOCK;
1108
1109  {
1110   HV *stash;
1111
1112   stash = gv_stashpvn(__PACKAGE__, __PACKAGE_LEN__, 1);
1113   newCONSTSUB(stash, "I_THREADSAFE", newSVuv(I_THREADSAFE));
1114   newCONSTSUB(stash, "I_FORKSAFE",   newSVuv(I_FORKSAFE));
1115
1116 #if I_THREADSAFE
1117   MY_CXT.tbl         = ptable_new();
1118   MY_CXT.owner       = aTHX;
1119 #endif
1120
1121   MY_CXT.map         = ptable_new();
1122   MY_CXT.global_code = NULL;
1123  }
1124
1125 #if I_MULTIPLICITY
1126  call_atexit(indirect_teardown, aTHX);
1127 #else
1128  call_atexit(indirect_teardown, NULL);
1129 #endif
1130
1131  return;
1132 }
1133
1134 /* --- XS ------------------------------------------------------------------ */
1135
1136 MODULE = indirect      PACKAGE = indirect
1137
1138 PROTOTYPES: ENABLE
1139
1140 BOOT:
1141 {
1142  indirect_setup();
1143 }
1144
1145 #if I_THREADSAFE
1146
1147 void
1148 CLONE(...)
1149 PROTOTYPE: DISABLE
1150 PREINIT:
1151  ptable *t;
1152  SV     *global_code_dup;
1153  GV     *gv;
1154 PPCODE:
1155  {
1156   indirect_ptable_clone_ud ud;
1157   dMY_CXT;
1158   t = ptable_new();
1159   indirect_ptable_clone_ud_init(ud, t, MY_CXT.owner);
1160   ptable_walk(MY_CXT.tbl, indirect_ptable_clone, &ud);
1161   global_code_dup = indirect_dup_inc(MY_CXT.global_code, &ud);
1162   indirect_ptable_clone_ud_deinit(ud);
1163  }
1164  {
1165   MY_CXT_CLONE;
1166   MY_CXT.map         = ptable_new();
1167   MY_CXT.tbl         = t;
1168   MY_CXT.owner       = aTHX;
1169   MY_CXT.global_code = global_code_dup;
1170   {
1171    int global_setup;
1172    I_LOADED_LOCK;
1173    global_setup = indirect_set_loaded_locked(&MY_CXT);
1174    assert(!global_setup);
1175    I_LOADED_UNLOCK;
1176   }
1177  }
1178  gv = gv_fetchpv(__PACKAGE__ "::_THREAD_CLEANUP", 0, SVt_PVCV);
1179  if (gv) {
1180   CV *cv = GvCV(gv);
1181   if (!PL_endav)
1182    PL_endav = newAV();
1183   SvREFCNT_inc(cv);
1184   if (!av_store(PL_endav, av_len(PL_endav) + 1, (SV *) cv))
1185    SvREFCNT_dec(cv);
1186   sv_magicext((SV *) PL_endav, NULL, PERL_MAGIC_ext, &indirect_endav_vtbl, NULL, 0);
1187  }
1188  XSRETURN(0);
1189
1190 void
1191 _THREAD_CLEANUP(...)
1192 PROTOTYPE: DISABLE
1193 PPCODE:
1194  indirect_thread_cleanup(aTHX_ NULL);
1195  XSRETURN(0);
1196
1197 #endif
1198
1199 SV *
1200 _tag(SV *value)
1201 PROTOTYPE: $
1202 CODE:
1203  RETVAL = indirect_tag(value);
1204 OUTPUT:
1205  RETVAL
1206
1207 void
1208 _global(SV *code)
1209 PROTOTYPE: $
1210 PPCODE:
1211  if (!SvOK(code))
1212   code = NULL;
1213  else if (SvROK(code))
1214   code = SvRV(code);
1215  {
1216   dMY_CXT;
1217   SvREFCNT_dec(MY_CXT.global_code);
1218   MY_CXT.global_code = SvREFCNT_inc(code);
1219  }
1220  XSRETURN(0);