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 #ifdef DEBUGGING
 105 # define I_ASSERT(C) assert(C)
 106 #else
 107 # define I_ASSERT(C)
 108 #endif
 109
 110 #ifndef I_WORKAROUND_REQUIRE_PROPAGATION
 111 # define I_WORKAROUND_REQUIRE_PROPAGATION !I_HAS_PERL(5, 10, 1)
 112 #endif
 113
 114 /* ... Thread safety and multiplicity ...................................... */
 115
 116 /* Safe unless stated otherwise in Makefile.PL */
 117 #ifndef I_FORKSAFE
 118 # define I_FORKSAFE 1
 119 #endif
 120
 121 #ifndef I_MULTIPLICITY
 122 # if defined(MULTIPLICITY)
 123 #  define I_MULTIPLICITY 1
 124 # else
 125 #  define I_MULTIPLICITY 0
 126 # endif
 127 #endif
 128 #if I_MULTIPLICITY
 129 # ifndef PERL_IMPLICIT_CONTEXT
 130 #  error MULTIPLICITY builds must set PERL_IMPLICIT_CONTEXT
 131 # endif
 132 #endif
 133 #if I_MULTIPLICITY && !defined(tTHX)
 134 # define tTHX PerlInterpreter*
 135 #endif
 136
 137 #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))
 138 # define I_THREADSAFE 1
 139 # ifndef MY_CXT_CLONE
 140 #  define MY_CXT_CLONE \
 141     dMY_CXT_SV;                                                      \
 142     my_cxt_t *my_cxtp = (my_cxt_t*)SvPVX(newSV(sizeof(my_cxt_t)-1)); \
 143     Copy(INT2PTR(my_cxt_t*, SvUV(my_cxt_sv)), my_cxtp, 1, my_cxt_t); \
 144     sv_setuv(my_cxt_sv, PTR2UV(my_cxtp))
 145 # endif
 146 #else
 147 # define I_THREADSAFE 0
 148 # undef  dMY_CXT
 149 # define dMY_CXT      dNOOP
 150 # undef  MY_CXT
 151 # define MY_CXT       indirect_globaldata
 152 # undef  START_MY_CXT
 153 # define START_MY_CXT static my_cxt_t MY_CXT;
 154 # undef  MY_CXT_INIT
 155 # define MY_CXT_INIT  NOOP
 156 # undef  MY_CXT_CLONE
 157 # define MY_CXT_CLONE NOOP
 158 #endif
 159
 160 #if I_THREADSAFE
 161 /* We must use preexistent global mutexes or we will never be able to destroy
 162  * them. */
 163 # if I_HAS_PERL(5, 9, 3)
 164 #  define I_LOADED_LOCK   MUTEX_LOCK(&PL_my_ctx_mutex)
 165 #  define I_LOADED_UNLOCK MUTEX_UNLOCK(&PL_my_ctx_mutex)
 166 # else
 167 #  define I_LOADED_LOCK   OP_REFCNT_LOCK
 168 #  define I_LOADED_UNLOCK OP_REFCNT_UNLOCK
 169 # endif
 170 #else
 171 # define I_LOADED_LOCK   NOOP
 172 # define I_LOADED_UNLOCK NOOP
 173 #endif
 174
 175 #if defined(OP_CHECK_MUTEX_LOCK) && defined(OP_CHECK_MUTEX_UNLOCK)
 176 # define I_CHECK_LOCK   OP_CHECK_MUTEX_LOCK
 177 # define I_CHECK_UNLOCK OP_CHECK_MUTEX_UNLOCK
 178 #elif I_HAS_PERL(5, 9, 3)
 179 # define I_CHECK_LOCK   OP_REFCNT_LOCK
 180 # define I_CHECK_UNLOCK OP_REFCNT_UNLOCK
 181 #else
 182 /* Before perl 5.9.3, indirect_ck_*() calls are already protected by the
 183  * I_LOADED mutex, which falls back to the OP_REFCNT mutex. Make sure we don't
 184  * lock it twice. */
 185 # define I_CHECK_LOCK   NOOP
 186 # define I_CHECK_UNLOCK NOOP
 187 #endif
 188
 189 typedef OP *(*indirect_ck_t)(pTHX_ OP *);
 190
 191 #ifdef wrap_op_checker
 192
 193 # define indirect_ck_replace(T, NC, OCP) wrap_op_checker((T), (NC), (OCP))
 194
 195 #else
 196
 197 static void indirect_ck_replace(pTHX_ OPCODE type, indirect_ck_t new_ck, indirect_ck_t *old_ck_p) {
 198 #define indirect_ck_replace(T, NC, OCP) indirect_ck_replace(aTHX_ (T), (NC), (OCP))
 199  I_CHECK_LOCK;
 200  if (!*old_ck_p) {
 201   *old_ck_p      = PL_check[type];
 202   PL_check[type] = new_ck;
 203  }
 204  I_CHECK_UNLOCK;
 205 }
 206
 207 #endif
 208
 209 static void indirect_ck_restore(pTHX_ OPCODE type, indirect_ck_t *old_ck_p) {
 210 #define indirect_ck_restore(T, OCP) indirect_ck_restore(aTHX_ (T), (OCP))
 211  I_CHECK_LOCK;
 212  if (*old_ck_p) {
 213   PL_check[type] = *old_ck_p;
 214   *old_ck_p      = 0;
 215  }
 216  I_CHECK_UNLOCK;
 217 }
 218
 219 /* --- Helpers ------------------------------------------------------------- */
 220
 221 /* ... Check if the module is loaded ....................................... */
 222
 223 static I32 indirect_loaded = 0;
 224
 225 #if I_THREADSAFE
 226
 227 #define PTABLE_NAME        ptable_loaded
 228 #define PTABLE_NEED_DELETE 1
 229 #define PTABLE_NEED_WALK   0
 230
 231 #include "ptable.h"
 232
 233 #define ptable_loaded_store(T, K, V) ptable_loaded_store(aPTBLMS_ (T), (K), (V))
 234 #define ptable_loaded_delete(T, K)   ptable_loaded_delete(aPTBLMS_ (T), (K))
 235 #define ptable_loaded_free(T)        ptable_loaded_free(aPTBLMS_ (T))
 236
 237 static ptable *indirect_loaded_cxts = NULL;
 238
 239 static int indirect_is_loaded(pTHX_ void *cxt) {
 240 #define indirect_is_loaded(C) indirect_is_loaded(aTHX_ (C))
 241  int res = 0;
 242
 243  I_LOADED_LOCK;
 244  if (indirect_loaded_cxts && ptable_fetch(indirect_loaded_cxts, cxt))
 245   res = 1;
 246  I_LOADED_UNLOCK;
 247
 248  return res;
 249 }
 250
 251 static int indirect_set_loaded_locked(pTHX_ void *cxt) {
 252 #define indirect_set_loaded_locked(C) indirect_set_loaded_locked(aTHX_ (C))
 253  int global_setup = 0;
 254
 255  if (indirect_loaded <= 0) {
 256   I_ASSERT(indirect_loaded == 0);
 257   I_ASSERT(!indirect_loaded_cxts);
 258   indirect_loaded_cxts = ptable_new();
 259   global_setup         = 1;
 260  }
 261  ++indirect_loaded;
 262  I_ASSERT(indirect_loaded_cxts);
 263  ptable_loaded_store(indirect_loaded_cxts, cxt, cxt);
 264
 265  return global_setup;
 266 }
 267
 268 static int indirect_clear_loaded_locked(pTHX_ void *cxt) {
 269 #define indirect_clear_loaded_locked(C) indirect_clear_loaded_locked(aTHX_ (C))
 270  int global_teardown = 0;
 271
 272  if (indirect_loaded > 1) {
 273   I_ASSERT(indirect_loaded_cxts);
 274   ptable_loaded_delete(indirect_loaded_cxts, cxt);
 275   --indirect_loaded;
 276  } else if (indirect_loaded_cxts) {
 277   I_ASSERT(indirect_loaded == 1);
 278   ptable_loaded_free(indirect_loaded_cxts);
 279   indirect_loaded_cxts = NULL;
 280   indirect_loaded      = 0;
 281   global_teardown      = 1;
 282  }
 283
 284  return global_teardown;
 285 }
 286
 287 #else
 288
 289 #define indirect_is_loaded(C)           (indirect_loaded > 0)
 290 #define indirect_set_loaded_locked(C)   ((indirect_loaded++ <= 0) ? 1 : 0)
 291 #define indirect_clear_loaded_locked(C) ((--indirect_loaded <= 0) ? 1 : 0)
 292
 293 #endif
 294
 295 /* ... Thread-safe hints ................................................... */
 296
 297 #if I_WORKAROUND_REQUIRE_PROPAGATION
 298
 299 typedef struct {
 300  SV *code;
 301  IV  require_tag;
 302 } indirect_hint_t;
 303
 304 #define I_HINT_STRUCT 1
 305
 306 #define I_HINT_CODE(H) ((H)->code)
 307
 308 #define I_HINT_FREE(H) {   \
 309  indirect_hint_t *h = (H); \
 310  SvREFCNT_dec(h->code);    \
 311  PerlMemShared_free(h);    \
 312 }
 313
 314 #else  /*  I_WORKAROUND_REQUIRE_PROPAGATION */
 315
 316 typedef SV indirect_hint_t;
 317
 318 #define I_HINT_STRUCT 0
 319
 320 #define I_HINT_CODE(H) (H)
 321
 322 #define I_HINT_FREE(H) SvREFCNT_dec(H);
 323
 324 #endif /* !I_WORKAROUND_REQUIRE_PROPAGATION */
 325
 326 #if I_THREADSAFE
 327
 328 #define PTABLE_NAME        ptable_hints
 329 #define PTABLE_VAL_FREE(V) I_HINT_FREE(V)
 330 #define PTABLE_NEED_DELETE 0
 331 #define PTABLE_NEED_WALK   1
 332
 333 #define pPTBL  pTHX
 334 #define pPTBL_ pTHX_
 335 #define aPTBL  aTHX
 336 #define aPTBL_ aTHX_
 337
 338 #include "ptable.h"
 339
 340 #define ptable_hints_store(T, K, V) ptable_hints_store(aTHX_ (T), (K), (V))
 341 #define ptable_hints_free(T)        ptable_hints_free(aTHX_ (T))
 342
 343 #endif /* I_THREADSAFE */
 344
 345 /* Define the op->str ptable here because we need to be able to clean it during
 346  * thread cleanup. */
 347
 348 typedef struct {
 349  char   *buf;
 350  STRLEN  pos;
 351  STRLEN  size;
 352  STRLEN  len;
 353  line_t  line;
 354 } indirect_op_info_t;
 355
 356 #define PTABLE_NAME        ptable
 357 #define PTABLE_VAL_FREE(V) if (V) { Safefree(((indirect_op_info_t *) (V))->buf); Safefree(V); }
 358 #define PTABLE_NEED_DELETE 1
 359 #define PTABLE_NEED_WALK   0
 360
 361 #define pPTBL  pTHX
 362 #define pPTBL_ pTHX_
 363 #define aPTBL  aTHX
 364 #define aPTBL_ aTHX_
 365
 366 #include "ptable.h"
 367
 368 #define ptable_store(T, K, V) ptable_store(aTHX_ (T), (K), (V))
 369 #define ptable_delete(T, K)   ptable_delete(aTHX_ (T), (K))
 370 #define ptable_clear(T)       ptable_clear(aTHX_ (T))
 371 #define ptable_free(T)        ptable_free(aTHX_ (T))
 372
 373 #define MY_CXT_KEY __PACKAGE__ "::_guts" XS_VERSION
 374
 375 typedef struct {
 376 #if I_THREADSAFE
 377  ptable *tbl; /* It really is a ptable_hints */
 378  tTHX    owner;
 379 #endif
 380  ptable *map;
 381  SV     *global_code;
 382 } my_cxt_t;
 383
 384 START_MY_CXT
 385
 386 #if I_THREADSAFE
 387
 388 typedef struct {
 389  ptable *tbl;
 390 #if I_HAS_PERL(5, 13, 2)
 391  CLONE_PARAMS *params;
 392 #else
 393  CLONE_PARAMS params;
 394 #endif
 395 } indirect_ptable_clone_ud;
 396
 397 #if I_HAS_PERL(5, 13, 2)
 398 # define indirect_ptable_clone_ud_init(U, T, O) \
 399    (U).tbl    = (T); \
 400    (U).params = Perl_clone_params_new((O), aTHX)
 401 # define indirect_ptable_clone_ud_deinit(U) Perl_clone_params_del((U).params)
 402 # define indirect_dup_inc(S, U)             SvREFCNT_inc(sv_dup((S), (U)->params))
 403 #else
 404 # define indirect_ptable_clone_ud_init(U, T, O) \
 405    (U).tbl               = (T);     \
 406    (U).params.stashes    = newAV(); \
 407    (U).params.flags      = 0;       \
 408    (U).params.proto_perl = (O)
 409 # define indirect_ptable_clone_ud_deinit(U) SvREFCNT_dec((U).params.stashes)
 410 # define indirect_dup_inc(S, U)             SvREFCNT_inc(sv_dup((S), &((U)->params)))
 411 #endif
 412
 413 static void indirect_ptable_clone(pTHX_ ptable_ent *ent, void *ud_) {
 414  indirect_ptable_clone_ud *ud = ud_;
 415  indirect_hint_t          *h1 = ent->val;
 416  indirect_hint_t          *h2;
 417
 418 #if I_HINT_STRUCT
 419
 420  h2              = PerlMemShared_malloc(sizeof *h2);
 421  h2->code        = indirect_dup_inc(h1->code, ud);
 422 #if I_WORKAROUND_REQUIRE_PROPAGATION
 423  h2->require_tag = PTR2IV(indirect_dup_inc(INT2PTR(SV *, h1->require_tag), ud));
 424 #endif
 425
 426 #else  /*  I_HINT_STRUCT */
 427
 428  h2 = indirect_dup_inc(h1, ud);
 429
 430 #endif /* !I_HINT_STRUCT */
 431
 432  ptable_hints_store(ud->tbl, ent->key, h2);
 433 }
 434
 435 #endif /* I_THREADSAFE */
 436
 437 #if I_WORKAROUND_REQUIRE_PROPAGATION
 438
 439 static IV indirect_require_tag(pTHX) {
 440 #define indirect_require_tag() indirect_require_tag(aTHX)
 441  const CV *cv, *outside;
 442
 443  cv = PL_compcv;
 444
 445  if (!cv) {
 446   /* If for some reason the pragma is operational at run-time, try to discover
 447    * the current cv in use. */
 448   const PERL_SI *si;
 449
 450   for (si = PL_curstackinfo; si; si = si->si_prev) {
 451    I32 cxix;
 452
 453    for (cxix = si->si_cxix; cxix >= 0; --cxix) {
 454     const PERL_CONTEXT *cx = si->si_cxstack + cxix;
 455
 456     switch (CxTYPE(cx)) {
 457      case CXt_SUB:
 458      case CXt_FORMAT:
 459       /* The propagation workaround is only needed up to 5.10.0 and at that
 460        * time format and sub contexts were still identical. And even later the
 461        * cv members offsets should have been kept the same. */
 462       cv = cx->blk_sub.cv;
 463       goto get_enclosing_cv;
 464      case CXt_EVAL:
 465       cv = cx->blk_eval.cv;
 466       goto get_enclosing_cv;
 467      default:
 468       break;
 469     }
 470    }
 471   }
 472
 473   cv = PL_main_cv;
 474  }
 475
 476 get_enclosing_cv:
 477  for (outside = CvOUTSIDE(cv); outside; outside = CvOUTSIDE(cv))
 478   cv = outside;
 479
 480  return PTR2IV(cv);
 481 }
 482
 483 #endif /* I_WORKAROUND_REQUIRE_PROPAGATION */
 484
 485 static SV *indirect_tag(pTHX_ SV *value) {
 486 #define indirect_tag(V) indirect_tag(aTHX_ (V))
 487  indirect_hint_t *h;
 488  SV              *code = NULL;
 489 #if I_THREADSAFE
 490  dMY_CXT;
 491
 492  if (!MY_CXT.tbl)
 493   return newSViv(0);
 494 #endif /* I_THREADSAFE */
 495
 496  if (SvROK(value)) {
 497   value = SvRV(value);
 498   if (SvTYPE(value) >= SVt_PVCV) {
 499    code = value;
 500    SvREFCNT_inc_simple_void_NN(code);
 501   }
 502  }
 503
 504 #if I_HINT_STRUCT
 505  h = PerlMemShared_malloc(sizeof *h);
 506  h->code        = code;
 507 # if I_WORKAROUND_REQUIRE_PROPAGATION
 508  h->require_tag = indirect_require_tag();
 509 # endif /* I_WORKAROUND_REQUIRE_PROPAGATION */
 510 #else  /*  I_HINT_STRUCT */
 511  h = code;
 512 #endif /* !I_HINT_STRUCT */
 513
 514 #if I_THREADSAFE
 515  /* We only need for the key to be an unique tag for looking up the value later
 516   * Allocated memory provides convenient unique identifiers, so that's why we
 517   * use the hint as the key itself. */
 518  ptable_hints_store(MY_CXT.tbl, h, h);
 519 #endif /* I_THREADSAFE */
 520
 521  return newSViv(PTR2IV(h));
 522 }
 523
 524 static SV *indirect_detag(pTHX_ const SV *hint) {
 525 #define indirect_detag(H) indirect_detag(aTHX_ (H))
 526  indirect_hint_t *h;
 527 #if I_THREADSAFE || I_WORKAROUND_REQUIRE_PROPAGATION
 528  dMY_CXT;
 529 #endif
 530
 531 #if I_THREADSAFE
 532  if (!MY_CXT.tbl)
 533   return NULL;
 534 #endif /* I_THREADSAFE */
 535
 536  h = INT2PTR(indirect_hint_t *, SvIVX(hint));
 537 #if I_THREADSAFE
 538  h = ptable_fetch(MY_CXT.tbl, h);
 539 #endif /* I_THREADSAFE */
 540
 541 #if I_WORKAROUND_REQUIRE_PROPAGATION
 542  if (indirect_require_tag() != h->require_tag)
 543   return MY_CXT.global_code;
 544 #endif /* I_WORKAROUND_REQUIRE_PROPAGATION */
 545
 546  return I_HINT_CODE(h);
 547 }
 548
 549 static VOL U32 indirect_hash = 0;
 550
 551 static SV *indirect_hint(pTHX) {
 552 #define indirect_hint() indirect_hint(aTHX)
 553  SV *hint = NULL;
 554
 555  if (IN_PERL_RUNTIME)
 556   return NULL;
 557
 558 #if I_HAS_PERL(5, 10, 0) || defined(PL_parser)
 559  if (!PL_parser)
 560   return NULL;
 561 #endif
 562
 563 #ifdef cop_hints_fetch_pvn
 564  hint = cop_hints_fetch_pvn(PL_curcop, __PACKAGE__, __PACKAGE_LEN__,
 565                                                               indirect_hash, 0);
 566 #elif I_HAS_PERL(5, 9, 5)
 567  hint = Perl_refcounted_he_fetch(aTHX_ PL_curcop->cop_hints_hash,
 568                                        NULL,
 569                                        __PACKAGE__, __PACKAGE_LEN__,
 570                                        0,
 571                                        indirect_hash);
 572 #else
 573  {
 574   SV **val = hv_fetch(GvHV(PL_hintgv), __PACKAGE__, __PACKAGE_LEN__, 0);
 575   if (val)
 576    hint = *val;
 577  }
 578 #endif
 579
 580  if (hint && SvIOK(hint)) {
 581   return indirect_detag(hint);
 582  } else {
 583   dMY_CXT;
 584   if (indirect_is_loaded(&MY_CXT))
 585    return MY_CXT.global_code;
 586   else
 587    return NULL;
 588  }
 589 }
 590
 591 /* ... op -> source position ............................................... */
 592
 593 static void indirect_map_store(pTHX_ const OP *o, STRLEN pos, SV *sv, line_t line) {
 594 #define indirect_map_store(O, P, N, L) indirect_map_store(aTHX_ (O), (P), (N), (L))
 595  indirect_op_info_t *oi;
 596  const char *s;
 597  STRLEN len;
 598  dMY_CXT;
 599
 600  /* No need to check for MY_CXT.map != NULL because this code path is always
 601   * guarded by indirect_hint(). */
 602
 603  if (!(oi = ptable_fetch(MY_CXT.map, o))) {
 604   Newx(oi, 1, indirect_op_info_t);
 605   ptable_store(MY_CXT.map, o, oi);
 606   oi->buf  = NULL;
 607   oi->size = 0;
 608  }
 609
 610  if (sv) {
 611   s = SvPV_const(sv, len);
 612  } else {
 613   s   = "{";
 614   len = 1;
 615  }
 616
 617  if (len > oi->size) {
 618   Safefree(oi->buf);
 619   Newx(oi->buf, len, char);
 620   oi->size = len;
 621  }
 622  Copy(s, oi->buf, len, char);
 623
 624  oi->len  = len;
 625  oi->pos  = pos;
 626  oi->line = line;
 627 }
 628
 629 static const indirect_op_info_t *indirect_map_fetch(pTHX_ const OP *o) {
 630 #define indirect_map_fetch(O) indirect_map_fetch(aTHX_ (O))
 631  dMY_CXT;
 632
 633  /* No need to check for MY_CXT.map != NULL because this code path is always
 634   * guarded by indirect_hint(). */
 635
 636  return ptable_fetch(MY_CXT.map, o);
 637 }
 638
 639 static void indirect_map_delete(pTHX_ const OP *o) {
 640 #define indirect_map_delete(O) indirect_map_delete(aTHX_ (O))
 641  dMY_CXT;
 642
 643  if (indirect_is_loaded(&MY_CXT) && MY_CXT.map)
 644   ptable_delete(MY_CXT.map, o);
 645 }
 646
 647 /* --- Safe version of call_sv() ------------------------------------------- */
 648
 649 static I32 indirect_call_sv(pTHX_ SV *sv, I32 flags) {
 650 #define indirect_call_sv(S, F) indirect_call_sv(aTHX_ (S), (F))
 651  I32          ret, cxix;
 652  PERL_CONTEXT saved_cx;
 653  SV          *saved_errsv = NULL;
 654
 655  if (SvTRUE(ERRSV)) {
 656   if (IN_PERL_COMPILETIME && PL_errors)
 657    sv_catsv(PL_errors, ERRSV);
 658   else
 659    saved_errsv = newSVsv(ERRSV);
 660   SvCUR_set(ERRSV, 0);
 661  }
 662
 663  cxix     = (cxstack_ix < cxstack_max) ? (cxstack_ix + 1) : Perl_cxinc(aTHX);
 664  /* The last popped context will be reused by call_sv(), but our callers may
 665   * still need its previous value. Back it up so that it isn't clobbered. */
 666  saved_cx = cxstack[cxix];
 667
 668  ret = call_sv(sv, flags | G_EVAL);
 669
 670  cxstack[cxix] = saved_cx;
 671
 672  if (SvTRUE(ERRSV)) {
 673   /* Discard the old ERRSV, and reuse the variable to temporarily store the
 674    * new one. */
 675   if (saved_errsv)
 676    sv_setsv(saved_errsv, ERRSV);
 677   else
 678    saved_errsv = newSVsv(ERRSV);
 679   SvCUR_set(ERRSV, 0);
 680   /* Immediately flush all errors. */
 681   if (IN_PERL_COMPILETIME) {
 682 #if I_HAS_PERL(5, 10, 0) || defined(PL_parser)
 683    if (PL_parser)
 684     ++PL_parser->error_count;
 685 #elif defined(PL_error_count)
 686    ++PL_error_count;
 687 #else
 688    ++PL_Ierror_count;
 689 #endif
 690    if (PL_errors) {
 691     sv_setsv(ERRSV, PL_errors);
 692     SvCUR_set(PL_errors, 0);
 693    }
 694   }
 695   sv_catsv(ERRSV, saved_errsv);
 696   SvREFCNT_dec(saved_errsv);
 697   croak(NULL);
 698  } else if (saved_errsv) {
 699   /* If IN_PERL_COMPILETIME && PL_errors, then the old ERRSV has already been
 700    * added to PL_errors. Otherwise, just restore it to ERRSV, as if no eval
 701    * block has ever been executed. */
 702   sv_setsv(ERRSV, saved_errsv);
 703   SvREFCNT_dec(saved_errsv);
 704  }
 705
 706  return ret;
 707 }
 708
 709 /* --- Check functions ----------------------------------------------------- */
 710
 711 static int indirect_find(pTHX_ SV *name_sv, const char *line_bufptr, STRLEN *name_pos) {
 712 #define indirect_find(NSV, LBP, NP) indirect_find(aTHX_ (NSV), (LBP), (NP))
 713  STRLEN      name_len, line_len;
 714  const char *name, *name_end;
 715  const char *line, *line_end;
 716  const char *p;
 717
 718  line     = SvPV_const(PL_linestr, line_len);
 719  line_end = line + line_len;
 720
 721  name = SvPV_const(name_sv, name_len);
 722  if (name_len >= 1 && *name == '$') {
 723   ++name;
 724   --name_len;
 725   while (line_bufptr < line_end && *line_bufptr != '$')
 726    ++line_bufptr;
 727   if (line_bufptr >= line_end)
 728    return 0;
 729  }
 730  name_end = name + name_len;
 731
 732  p = line_bufptr;
 733  while (1) {
 734   p = ninstr(p, line_end, name, name_end);
 735   if (!p)
 736    return 0;
 737   if (!isALNUM(p[name_len]))
 738    break;
 739   /* p points to a word that has name as prefix, skip the rest of the word */
 740   p += name_len + 1;
 741   while (isALNUM(*p))
 742    ++p;
 743  }
 744
 745  *name_pos = p - line;
 746
 747  return 1;
 748 }
 749
 750 /* ... ck_const ............................................................ */
 751
 752 static OP *(*indirect_old_ck_const)(pTHX_ OP *) = 0;
 753
 754 static OP *indirect_ck_const(pTHX_ OP *o) {
 755  o = indirect_old_ck_const(aTHX_ o);
 756
 757  if (indirect_hint()) {
 758   SV *sv = cSVOPo_sv;
 759
 760   if (SvPOK(sv) && (SvTYPE(sv) >= SVt_PV)) {
 761    STRLEN pos;
 762
 763    if (indirect_find(sv, PL_oldbufptr, &pos)) {
 764     STRLEN len;
 765
 766     /* If the constant is equal to the current package name, try to look for
 767      * a "__PACKAGE__" coming before what we got. We only need to check this
 768      * when we already had a match because __PACKAGE__ can only appear in
 769      * direct method calls ("new __PACKAGE__" is a syntax error). */
 770     len = SvCUR(sv);
 771     if (PL_curstash
 772         && len == (STRLEN) HvNAMELEN_get(PL_curstash)
 773         && memcmp(SvPVX(sv), HvNAME_get(PL_curstash), len) == 0) {
 774      STRLEN pos_pkg;
 775      SV    *pkg = sv_newmortal();
 776      sv_setpvn(pkg, "__PACKAGE__", sizeof("__PACKAGE__")-1);
 777
 778      if (indirect_find(pkg, PL_oldbufptr, &pos_pkg) && pos_pkg < pos) {
 779       sv  = pkg;
 780       pos = pos_pkg;
 781      }
 782     }
 783
 784     indirect_map_store(o, pos, sv, CopLINE(&PL_compiling));
 785     return o;
 786    }
 787   }
 788  }
 789
 790  indirect_map_delete(o);
 791  return o;
 792 }
 793
 794 /* ... ck_rv2sv ............................................................ */
 795
 796 static OP *(*indirect_old_ck_rv2sv)(pTHX_ OP *) = 0;
 797
 798 static OP *indirect_ck_rv2sv(pTHX_ OP *o) {
 799  if (indirect_hint()) {
 800   OP *op = cUNOPo->op_first;
 801   SV *sv;
 802   const char *name = NULL;
 803   STRLEN pos, len;
 804   OPCODE type = (OPCODE) op->op_type;
 805
 806   switch (type) {
 807    case OP_GV:
 808    case OP_GVSV: {
 809     GV *gv = cGVOPx_gv(op);
 810     name = GvNAME(gv);
 811     len  = GvNAMELEN(gv);
 812     break;
 813    }
 814    default:
 815     if ((PL_opargs[type] & OA_CLASS_MASK) == OA_SVOP) {
 816      SV *nsv = cSVOPx_sv(op);
 817      if (SvPOK(nsv) && (SvTYPE(nsv) >= SVt_PV))
 818       name = SvPV_const(nsv, len);
 819     }
 820   }
 821   if (!name)
 822    goto done;
 823
 824   sv = sv_2mortal(newSVpvn("$", 1));
 825   sv_catpvn_nomg(sv, name, len);
 826   if (!indirect_find(sv, PL_oldbufptr, &pos)) {
 827    /* If it failed, retry without the current stash */
 828    const char *stash = HvNAME_get(PL_curstash);
 829    STRLEN stashlen = HvNAMELEN_get(PL_curstash);
 830
 831    if ((len < stashlen + 2) || strnNE(name, stash, stashlen)
 832        || name[stashlen] != ':' || name[stashlen+1] != ':') {
 833     /* Failed again ? Try to remove main */
 834     stash = "main";
 835     stashlen = 4;
 836     if ((len < stashlen + 2) || strnNE(name, stash, stashlen)
 837         || name[stashlen] != ':' || name[stashlen+1] != ':')
 838      goto done;
 839    }
 840
 841    sv_setpvn(sv, "$", 1);
 842    stashlen += 2;
 843    sv_catpvn_nomg(sv, name + stashlen, len - stashlen);
 844    if (!indirect_find(sv, PL_oldbufptr, &pos))
 845     goto done;
 846   }
 847
 848   o = indirect_old_ck_rv2sv(aTHX_ o);
 849
 850   indirect_map_store(o, pos, sv, CopLINE(&PL_compiling));
 851   return o;
 852  }
 853
 854 done:
 855  o = indirect_old_ck_rv2sv(aTHX_ o);
 856
 857  indirect_map_delete(o);
 858  return o;
 859 }
 860
 861 /* ... ck_padany ........................................................... */
 862
 863 static OP *(*indirect_old_ck_padany)(pTHX_ OP *) = 0;
 864
 865 static OP *indirect_ck_padany(pTHX_ OP *o) {
 866  o = indirect_old_ck_padany(aTHX_ o);
 867
 868  if (indirect_hint()) {
 869   SV *sv;
 870   const char *s = PL_oldbufptr, *t = PL_bufptr - 1;
 871
 872   while (s < t && isSPACE(*s)) ++s;
 873   if (*s == '$' && ++s <= t) {
 874    while (s < t && isSPACE(*s)) ++s;
 875    while (s < t && isSPACE(*t)) --t;
 876    sv = sv_2mortal(newSVpvn("$", 1));
 877    sv_catpvn_nomg(sv, s, t - s + 1);
 878    indirect_map_store(o, s - SvPVX_const(PL_linestr),
 879                          sv, CopLINE(&PL_compiling));
 880    return o;
 881   }
 882  }
 883
 884  indirect_map_delete(o);
 885  return o;
 886 }
 887
 888 /* ... ck_scope ............................................................ */
 889
 890 static OP *(*indirect_old_ck_scope)  (pTHX_ OP *) = 0;
 891 static OP *(*indirect_old_ck_lineseq)(pTHX_ OP *) = 0;
 892
 893 static OP *indirect_ck_scope(pTHX_ OP *o) {
 894  OP *(*old_ck)(pTHX_ OP *) = 0;
 895
 896  switch (o->op_type) {
 897   case OP_SCOPE:   old_ck = indirect_old_ck_scope;   break;
 898   case OP_LINESEQ: old_ck = indirect_old_ck_lineseq; break;
 899  }
 900  o = old_ck(aTHX_ o);
 901
 902  if (indirect_hint()) {
 903   indirect_map_store(o, PL_oldbufptr - SvPVX_const(PL_linestr),
 904                         NULL, CopLINE(&PL_compiling));
 905   return o;
 906  }
 907
 908  indirect_map_delete(o);
 909  return o;
 910 }
 911
 912 /* We don't need to clean the map entries for leave ops because they can only
 913  * be created by mutating from a lineseq. */
 914
 915 /* ... ck_method ........................................................... */
 916
 917 static OP *(*indirect_old_ck_method)(pTHX_ OP *) = 0;
 918
 919 static OP *indirect_ck_method(pTHX_ OP *o) {
 920  if (indirect_hint()) {
 921   OP *op = cUNOPo->op_first;
 922
 923   /* Indirect method call is only possible when the method is a bareword, so
 924    * don't trip up on $obj->$meth. */
 925   if (op && op->op_type == OP_CONST) {
 926    const indirect_op_info_t *oi = indirect_map_fetch(op);
 927    STRLEN pos;
 928    line_t line;
 929    SV *sv;
 930
 931    if (!oi)
 932     goto done;
 933
 934    sv   = sv_2mortal(newSVpvn(oi->buf, oi->len));
 935    pos  = oi->pos;
 936    /* Keep the old line so that we really point to the first line of the
 937     * expression. */
 938    line = oi->line;
 939
 940    o = indirect_old_ck_method(aTHX_ o);
 941    /* o may now be a method_named */
 942
 943    indirect_map_store(o, pos, sv, line);
 944    return o;
 945   }
 946  }
 947
 948 done:
 949  o = indirect_old_ck_method(aTHX_ o);
 950
 951  indirect_map_delete(o);
 952  return o;
 953 }
 954
 955 /* ... ck_method_named ..................................................... */
 956
 957 /* "use foo/no foo" compiles its call to import/unimport directly to a
 958  * method_named op. */
 959
 960 static OP *(*indirect_old_ck_method_named)(pTHX_ OP *) = 0;
 961
 962 static OP *indirect_ck_method_named(pTHX_ OP *o) {
 963  if (indirect_hint()) {
 964   STRLEN pos;
 965   line_t line;
 966   SV *sv;
 967
 968   sv = cSVOPo_sv;
 969   if (!SvPOK(sv) || (SvTYPE(sv) < SVt_PV))
 970    goto done;
 971   sv = sv_mortalcopy(sv);
 972
 973   if (!indirect_find(sv, PL_oldbufptr, &pos))
 974    goto done;
 975   line = CopLINE(&PL_compiling);
 976
 977   o = indirect_old_ck_method_named(aTHX_ o);
 978
 979   indirect_map_store(o, pos, sv, line);
 980   return o;
 981  }
 982
 983 done:
 984  o = indirect_old_ck_method_named(aTHX_ o);
 985
 986  indirect_map_delete(o);
 987  return o;
 988 }
 989
 990 /* ... ck_entersub ......................................................... */
 991
 992 static OP *(*indirect_old_ck_entersub)(pTHX_ OP *) = 0;
 993
 994 static OP *indirect_ck_entersub(pTHX_ OP *o) {
 995  SV *code = indirect_hint();
 996
 997  o = indirect_old_ck_entersub(aTHX_ o);
 998
 999  if (code) {
1000   const indirect_op_info_t *moi, *ooi;
1001   OP     *mop, *oop;
1002   LISTOP *lop;
1003
1004   oop = o;
1005   do {
1006    lop = (LISTOP *) oop;
1007    if (!(lop->op_flags & OPf_KIDS))
1008     goto done;
1009    oop = lop->op_first;
1010   } while (oop->op_type != OP_PUSHMARK);
1011   oop = OpSIBLING(oop);
1012   mop = lop->op_last;
1013
1014   if (!oop)
1015    goto done;
1016
1017   switch (oop->op_type) {
1018    case OP_CONST:
1019    case OP_RV2SV:
1020    case OP_PADSV:
1021    case OP_SCOPE:
1022    case OP_LEAVE:
1023     break;
1024    default:
1025     goto done;
1026   }
1027
1028   if (mop->op_type == OP_METHOD)
1029    mop = cUNOPx(mop)->op_first;
1030   else if (mop->op_type != OP_METHOD_NAMED)
1031    goto done;
1032
1033   moi = indirect_map_fetch(mop);
1034   if (!moi)
1035    goto done;
1036
1037   ooi = indirect_map_fetch(oop);
1038   if (!ooi)
1039    goto done;
1040
1041   /* When positions are identical, the method and the object must have the
1042    * same name. But it also means that it is an indirect call, as "foo->foo"
1043    * results in different positions. */
1044   if (   moi->line < ooi->line
1045       || (moi->line == ooi->line && moi->pos <= ooi->pos)) {
1046    SV *file;
1047    dSP;
1048
1049    ENTER;
1050    SAVETMPS;
1051
1052 #ifdef USE_ITHREADS
1053    file = sv_2mortal(newSVpv(CopFILE(&PL_compiling), 0));
1054 #else
1055    file = sv_mortalcopy(CopFILESV(&PL_compiling));
1056 #endif
1057
1058    PUSHMARK(SP);
1059    EXTEND(SP, 4);
1060    mPUSHp(ooi->buf, ooi->len);
1061    mPUSHp(moi->buf, moi->len);
1062    PUSHs(file);
1063    mPUSHu(moi->line);
1064    PUTBACK;
1065
1066    indirect_call_sv(code, G_VOID);
1067
1068    PUTBACK;
1069
1070    FREETMPS;
1071    LEAVE;
1072   }
1073  }
1074
1075 done:
1076  return o;
1077 }
1078
1079 /* --- Module setup/teardown ----------------------------------------------- */
1080
1081 static void indirect_teardown(pTHX_ void *interp) {
1082  dMY_CXT;
1083
1084  I_LOADED_LOCK;
1085
1086  if (indirect_clear_loaded_locked(&MY_CXT)) {
1087   indirect_ck_restore(OP_CONST,   &indirect_old_ck_const);
1088   indirect_ck_restore(OP_RV2SV,   &indirect_old_ck_rv2sv);
1089   indirect_ck_restore(OP_PADANY,  &indirect_old_ck_padany);
1090   indirect_ck_restore(OP_SCOPE,   &indirect_old_ck_scope);
1091   indirect_ck_restore(OP_LINESEQ, &indirect_old_ck_lineseq);
1092
1093   indirect_ck_restore(OP_METHOD,       &indirect_old_ck_method);
1094   indirect_ck_restore(OP_METHOD_NAMED, &indirect_old_ck_method_named);
1095   indirect_ck_restore(OP_ENTERSUB,     &indirect_old_ck_entersub);
1096  }
1097
1098  I_LOADED_UNLOCK;
1099
1100  SvREFCNT_dec(MY_CXT.global_code);
1101  MY_CXT.global_code = NULL;
1102
1103  ptable_free(MY_CXT.map);
1104  MY_CXT.map = NULL;
1105
1106 #if I_THREADSAFE
1107  ptable_hints_free(MY_CXT.tbl);
1108  MY_CXT.tbl = NULL;
1109 #endif
1110
1111  return;
1112 }
1113
1114 static void indirect_setup(pTHX) {
1115 #define indirect_setup() indirect_setup(aTHX)
1116  MY_CXT_INIT; /* Takes/release PL_my_ctx_mutex */
1117
1118  I_LOADED_LOCK;
1119
1120  if (indirect_set_loaded_locked(&MY_CXT)) {
1121   PERL_HASH(indirect_hash, __PACKAGE__, __PACKAGE_LEN__);
1122
1123   indirect_ck_replace(OP_CONST,   indirect_ck_const,  &indirect_old_ck_const);
1124   indirect_ck_replace(OP_RV2SV,   indirect_ck_rv2sv,  &indirect_old_ck_rv2sv);
1125   indirect_ck_replace(OP_PADANY,  indirect_ck_padany, &indirect_old_ck_padany);
1126   indirect_ck_replace(OP_SCOPE,   indirect_ck_scope,  &indirect_old_ck_scope);
1127   indirect_ck_replace(OP_LINESEQ, indirect_ck_scope,  &indirect_old_ck_lineseq);
1128
1129   indirect_ck_replace(OP_METHOD,       indirect_ck_method,
1130                                        &indirect_old_ck_method);
1131   indirect_ck_replace(OP_METHOD_NAMED, indirect_ck_method_named,
1132                                        &indirect_old_ck_method_named);
1133   indirect_ck_replace(OP_ENTERSUB,     indirect_ck_entersub,
1134                                        &indirect_old_ck_entersub);
1135  }
1136
1137  I_LOADED_UNLOCK;
1138
1139  {
1140   HV *stash;
1141
1142   stash = gv_stashpvn(__PACKAGE__, __PACKAGE_LEN__, 1);
1143   newCONSTSUB(stash, "I_THREADSAFE", newSVuv(I_THREADSAFE));
1144   newCONSTSUB(stash, "I_FORKSAFE",   newSVuv(I_FORKSAFE));
1145
1146 #if I_THREADSAFE
1147   MY_CXT.tbl         = ptable_new();
1148   MY_CXT.owner       = aTHX;
1149 #endif
1150
1151   MY_CXT.map         = ptable_new();
1152   MY_CXT.global_code = NULL;
1153  }
1154
1155  call_atexit(indirect_teardown, NULL);
1156
1157  return;
1158 }
1159
1160 /* --- XS ------------------------------------------------------------------ */
1161
1162 MODULE = indirect      PACKAGE = indirect
1163
1164 PROTOTYPES: ENABLE
1165
1166 BOOT:
1167 {
1168  indirect_setup();
1169 }
1170
1171 #if I_THREADSAFE
1172
1173 void
1174 CLONE(...)
1175 PROTOTYPE: DISABLE
1176 PREINIT:
1177  ptable *t;
1178  SV     *global_code_dup;
1179 PPCODE:
1180  {
1181   indirect_ptable_clone_ud ud;
1182   dMY_CXT;
1183   t = ptable_new();
1184   indirect_ptable_clone_ud_init(ud, t, MY_CXT.owner);
1185   ptable_walk(MY_CXT.tbl, indirect_ptable_clone, &ud);
1186   global_code_dup = indirect_dup_inc(MY_CXT.global_code, &ud);
1187   indirect_ptable_clone_ud_deinit(ud);
1188  }
1189  {
1190   MY_CXT_CLONE;
1191   MY_CXT.map         = ptable_new();
1192   MY_CXT.tbl         = t;
1193   MY_CXT.owner       = aTHX;
1194   MY_CXT.global_code = global_code_dup;
1195   {
1196    int global_setup;
1197    I_LOADED_LOCK;
1198    global_setup = indirect_set_loaded_locked(&MY_CXT);
1199    I_ASSERT(!global_setup);
1200    I_LOADED_UNLOCK;
1201   }
1202  }
1203  XSRETURN(0);
1204
1205 #endif /* I_THREADSAFE */
1206
1207 SV *
1208 _tag(SV *value)
1209 PROTOTYPE: $
1210 CODE:
1211  RETVAL = indirect_tag(value);
1212 OUTPUT:
1213  RETVAL
1214
1215 void
1216 _global(SV *code)
1217 PROTOTYPE: $
1218 PPCODE:
1219  if (!SvOK(code))
1220   code = NULL;
1221  else if (SvROK(code))
1222   code = SvRV(code);
1223  {
1224   dMY_CXT;
1225   SvREFCNT_dec(MY_CXT.global_code);
1226   MY_CXT.global_code = SvREFCNT_inc(code);
1227  }
1228  XSRETURN(0);