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