cop.h

   1 /*    cop.h
   2  *
   3  *    Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
   4  *    2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 by Larry Wall and others
   5  *
   6  *    You may distribute under the terms of either the GNU General Public
   7  *    License or the Artistic License, as specified in the README file.
   8  *
   9  * Control ops (cops) are one of the two ops OP_NEXTSTATE and OP_DBSTATE,
  10  * that (loosely speaking) are statement separators.
  11  * They hold information important for lexical state and error reporting.
  12  * At run time, PL_curcop is set to point to the most recently executed cop,
  13  * and thus can be used to determine our current state.
  14  */
  15
  16 /* A jmpenv packages the state required to perform a proper non-local jump.
  17  * Note that there is a PL_start_env initialized when perl starts, and
  18  * PL_top_env points to this initially, so PL_top_env should always be
  19  * non-null.
  20  *
  21  * Existence of a non-null PL_top_env->je_prev implies it is valid to call
  22  * longjmp() at that runlevel (we make sure PL_start_env.je_prev is always
  23  * null to ensure this).
  24  *
  25  * je_mustcatch, when set at any runlevel to TRUE, means eval ops must
  26  * establish a local jmpenv to handle exception traps.  Care must be taken
  27  * to restore the previous value of je_mustcatch before exiting the
  28  * stack frame iff JMPENV_PUSH was not called in that stack frame.
  29  * GSAR 97-03-27
  30  */
  31
  32 struct jmpenv {
  33     struct jmpenv *     je_prev;
  34     Sigjmp_buf          je_buf;         /* uninit if je_prev is NULL */
  35     int                 je_ret;         /* last exception thrown */
  36     bool                je_mustcatch;   /* need to call longjmp()? */
  37     U16                 je_old_delaymagic; /* saved PL_delaymagic */
  38 };
  39
  40 typedef struct jmpenv JMPENV;
  41
  42 /*
  43  * How to build the first jmpenv.
  44  *
  45  * top_env needs to be non-zero. It points to an area
  46  * in which longjmp() stuff is stored, as C callstack
  47  * info there at least is thread specific this has to
  48  * be per-thread. Otherwise a 'die' in a thread gives
  49  * that thread the C stack of last thread to do an eval {}!
  50  */
  51
  52 #define JMPENV_BOOTSTRAP \
  53     STMT_START {                                \
  54         PERL_POISON_EXPR(PoisonNew(&PL_start_env, 1, JMPENV));\
  55         PL_top_env = &PL_start_env;             \
  56         PL_start_env.je_prev = NULL;            \
  57         PL_start_env.je_ret = -1;               \
  58         PL_start_env.je_mustcatch = TRUE;       \
  59         PL_start_env.je_old_delaymagic = 0;     \
  60     } STMT_END
  61
  62 /*
  63  *   PERL_FLEXIBLE_EXCEPTIONS
  64  *
  65  * All the flexible exceptions code has been removed.
  66  * See the following threads for details:
  67  *
  68  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/2004-07/msg00378.html
  69  *
  70  * Joshua's original patches (which weren't applied) and discussion:
  71  *
  72  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01396.html
  73  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01489.html
  74  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01491.html
  75  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01608.html
  76  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg02144.html
  77  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg02998.html
  78  *
  79  * Chip's reworked patch and discussion:
  80  *
  81  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1999-03/msg00520.html
  82  *
  83  * The flaw in these patches (which went unnoticed at the time) was
  84  * that they moved some code that could potentially die() out of the
  85  * region protected by the setjmp()s.  This caused exceptions within
  86  * END blocks and such to not be handled by the correct setjmp().
  87  *
  88  * The original patches that introduces flexible exceptions were:
  89  *
  90  * http://perl5.git.perl.org/perl.git/commit/312caa8e97f1c7ee342a9895c2f0e749625b4929
  91  * http://perl5.git.perl.org/perl.git/commit/14dd3ad8c9bf82cf09798a22cc89a9862dfd6d1a
  92  *
  93  */
  94
  95 #define dJMPENV         JMPENV cur_env
  96
  97 #define JMPENV_PUSH(v) \
  98     STMT_START {                                                        \
  99         DEBUG_l({                                                       \
 100             int i = 0; JMPENV *p = PL_top_env;                          \
 101             while (p) { i++; p = p->je_prev; }                          \
 102             Perl_deb(aTHX_ "JUMPENV_PUSH level=%d at %s:%d\n",          \
 103                          i,  __FILE__, __LINE__);})                     \
 104         cur_env.je_prev = PL_top_env;                                   \
 105         cur_env.je_ret = PerlProc_setjmp(cur_env.je_buf, SCOPE_SAVES_SIGNAL_MASK);              \
 106         PL_top_env = &cur_env;                                          \
 107         cur_env.je_mustcatch = FALSE;                                   \
 108         cur_env.je_old_delaymagic = PL_delaymagic;                      \
 109         (v) = cur_env.je_ret;                                           \
 110     } STMT_END
 111
 112 #define JMPENV_POP \
 113     STMT_START {                                                        \
 114         DEBUG_l({                                                       \
 115             int i = -1; JMPENV *p = PL_top_env;                         \
 116             while (p) { i++; p = p->je_prev; }                          \
 117             Perl_deb(aTHX_ "JUMPENV_POP level=%d at %s:%d\n",           \
 118                          i, __FILE__, __LINE__);})                      \
 119         assert(PL_top_env == &cur_env);                                 \
 120         PL_delaymagic = cur_env.je_old_delaymagic;                      \
 121         PL_top_env = cur_env.je_prev;                                   \
 122     } STMT_END
 123
 124 #define JMPENV_JUMP(v) \
 125     STMT_START {                                                \
 126         DEBUG_l({                                               \
 127             int i = -1; JMPENV *p = PL_top_env;                 \
 128             while (p) { i++; p = p->je_prev; }                  \
 129             Perl_deb(aTHX_ "JUMPENV_JUMP(%d) level=%d at %s:%d\n", \
 130                          (int)v, i, __FILE__, __LINE__);})      \
 131         if (PL_top_env->je_prev)                                \
 132             PerlProc_longjmp(PL_top_env->je_buf, (v));          \
 133         if ((v) == 2)                                           \
 134             PerlProc_exit(STATUS_EXIT);                         \
 135         PerlIO_printf(PerlIO_stderr(), "panic: top_env, v=%d\n", (int)v); \
 136         PerlProc_exit(1);                                       \
 137     } STMT_END
 138
 139 #define CATCH_GET               (PL_top_env->je_mustcatch)
 140 #define CATCH_SET(v) \
 141     STMT_START {                                                        \
 142         DEBUG_l(                                                        \
 143             Perl_deb(aTHX_                                              \
 144                 "JUMPLEVEL set catch %d => %d (for %p) at %s:%d\n",     \
 145                  PL_top_env->je_mustcatch, v, (void*)PL_top_env,        \
 146                  __FILE__, __LINE__);)                                  \
 147         PL_top_env->je_mustcatch = (v);                                 \
 148     } STMT_END
 149
 150 /*
 151 =head1 COP Hint Hashes
 152 */
 153
 154 typedef struct refcounted_he COPHH;
 155
 156 #define COPHH_KEY_UTF8 REFCOUNTED_HE_KEY_UTF8
 157
 158 /*
 159 =for apidoc Amx|SV *|cophh_fetch_pvn|const COPHH *cophh|const char *keypv|STRLEN keylen|U32 hash|U32 flags
 160
 161 Look up the entry in the cop hints hash C<cophh> with the key specified by
 162 C<keypv> and C<keylen>.  If C<flags> has the C<COPHH_KEY_UTF8> bit set,
 163 the key octets are interpreted as UTF-8, otherwise they are interpreted
 164 as Latin-1.  C<hash> is a precomputed hash of the key string, or zero if
 165 it has not been precomputed.  Returns a mortal scalar copy of the value
 166 associated with the key, or C<&PL_sv_placeholder> if there is no value
 167 associated with the key.
 168
 169 =cut
 170 */
 171
 172 #define cophh_fetch_pvn(cophh, keypv, keylen, hash, flags) \
 173     Perl_refcounted_he_fetch_pvn(aTHX_ cophh, keypv, keylen, hash, flags)
 174
 175 /*
 176 =for apidoc Amx|SV *|cophh_fetch_pvs|const COPHH *cophh|const char *key|U32 flags
 177
 178 Like L</cophh_fetch_pvn>, but takes a literal string instead of a
 179 string/length pair, and no precomputed hash.
 180
 181 =cut
 182 */
 183
 184 #define cophh_fetch_pvs(cophh, key, flags) \
 185     Perl_refcounted_he_fetch_pvn(aTHX_ cophh, STR_WITH_LEN(key), 0, flags)
 186
 187 /*
 188 =for apidoc Amx|SV *|cophh_fetch_pv|const COPHH *cophh|const char *key|U32 hash|U32 flags
 189
 190 Like L</cophh_fetch_pvn>, but takes a nul-terminated string instead of
 191 a string/length pair.
 192
 193 =cut
 194 */
 195
 196 #define cophh_fetch_pv(cophh, key, hash, flags) \
 197     Perl_refcounted_he_fetch_pv(aTHX_ cophh, key, hash, flags)
 198
 199 /*
 200 =for apidoc Amx|SV *|cophh_fetch_sv|const COPHH *cophh|SV *key|U32 hash|U32 flags
 201
 202 Like L</cophh_fetch_pvn>, but takes a Perl scalar instead of a
 203 string/length pair.
 204
 205 =cut
 206 */
 207
 208 #define cophh_fetch_sv(cophh, key, hash, flags) \
 209     Perl_refcounted_he_fetch_sv(aTHX_ cophh, key, hash, flags)
 210
 211 /*
 212 =for apidoc Amx|HV *|cophh_2hv|const COPHH *cophh|U32 flags
 213
 214 Generates and returns a standard Perl hash representing the full set of
 215 key/value pairs in the cop hints hash C<cophh>.  C<flags> is currently
 216 unused and must be zero.
 217
 218 =cut
 219 */
 220
 221 #define cophh_2hv(cophh, flags) \
 222     Perl_refcounted_he_chain_2hv(aTHX_ cophh, flags)
 223
 224 /*
 225 =for apidoc Amx|COPHH *|cophh_copy|COPHH *cophh
 226
 227 Make and return a complete copy of the cop hints hash C<cophh>.
 228
 229 =cut
 230 */
 231
 232 #define cophh_copy(cophh) Perl_refcounted_he_inc(aTHX_ cophh)
 233
 234 /*
 235 =for apidoc Amx|void|cophh_free|COPHH *cophh
 236
 237 Discard the cop hints hash C<cophh>, freeing all resources associated
 238 with it.
 239
 240 =cut
 241 */
 242
 243 #define cophh_free(cophh) Perl_refcounted_he_free(aTHX_ cophh)
 244
 245 /*
 246 =for apidoc Amx|COPHH *|cophh_new_empty
 247
 248 Generate and return a fresh cop hints hash containing no entries.
 249
 250 =cut
 251 */
 252
 253 #define cophh_new_empty() ((COPHH *)NULL)
 254
 255 /*
 256 =for apidoc Amx|COPHH *|cophh_store_pvn|COPHH *cophh|const char *keypv|STRLEN keylen|U32 hash|SV *value|U32 flags
 257
 258 Stores a value, associated with a key, in the cop hints hash C<cophh>,
 259 and returns the modified hash.  The returned hash pointer is in general
 260 not the same as the hash pointer that was passed in.  The input hash is
 261 consumed by the function, and the pointer to it must not be subsequently
 262 used.  Use L</cophh_copy> if you need both hashes.
 263
 264 The key is specified by C<keypv> and C<keylen>.  If C<flags> has the
 265 C<COPHH_KEY_UTF8> bit set, the key octets are interpreted as UTF-8,
 266 otherwise they are interpreted as Latin-1.  C<hash> is a precomputed
 267 hash of the key string, or zero if it has not been precomputed.
 268
 269 C<value> is the scalar value to store for this key.  C<value> is copied
 270 by this function, which thus does not take ownership of any reference
 271 to it, and later changes to the scalar will not be reflected in the
 272 value visible in the cop hints hash.  Complex types of scalar will not
 273 be stored with referential integrity, but will be coerced to strings.
 274
 275 =cut
 276 */
 277
 278 #define cophh_store_pvn(cophh, keypv, keylen, hash, value, flags) \
 279     Perl_refcounted_he_new_pvn(aTHX_ cophh, keypv, keylen, hash, value, flags)
 280
 281 /*
 282 =for apidoc Amx|COPHH *|cophh_store_pvs|const COPHH *cophh|const char *key|SV *value|U32 flags
 283
 284 Like L</cophh_store_pvn>, but takes a literal string instead of a
 285 string/length pair, and no precomputed hash.
 286
 287 =cut
 288 */
 289
 290 #define cophh_store_pvs(cophh, key, value, flags) \
 291     Perl_refcounted_he_new_pvn(aTHX_ cophh, STR_WITH_LEN(key), 0, value, flags)
 292
 293 /*
 294 =for apidoc Amx|COPHH *|cophh_store_pv|const COPHH *cophh|const char *key|U32 hash|SV *value|U32 flags
 295
 296 Like L</cophh_store_pvn>, but takes a nul-terminated string instead of
 297 a string/length pair.
 298
 299 =cut
 300 */
 301
 302 #define cophh_store_pv(cophh, key, hash, value, flags) \
 303     Perl_refcounted_he_new_pv(aTHX_ cophh, key, hash, value, flags)
 304
 305 /*
 306 =for apidoc Amx|COPHH *|cophh_store_sv|const COPHH *cophh|SV *key|U32 hash|SV *value|U32 flags
 307
 308 Like L</cophh_store_pvn>, but takes a Perl scalar instead of a
 309 string/length pair.
 310
 311 =cut
 312 */
 313
 314 #define cophh_store_sv(cophh, key, hash, value, flags) \
 315     Perl_refcounted_he_new_sv(aTHX_ cophh, key, hash, value, flags)
 316
 317 /*
 318 =for apidoc Amx|COPHH *|cophh_delete_pvn|COPHH *cophh|const char *keypv|STRLEN keylen|U32 hash|U32 flags
 319
 320 Delete a key and its associated value from the cop hints hash C<cophh>,
 321 and returns the modified hash.  The returned hash pointer is in general
 322 not the same as the hash pointer that was passed in.  The input hash is
 323 consumed by the function, and the pointer to it must not be subsequently
 324 used.  Use L</cophh_copy> if you need both hashes.
 325
 326 The key is specified by C<keypv> and C<keylen>.  If C<flags> has the
 327 C<COPHH_KEY_UTF8> bit set, the key octets are interpreted as UTF-8,
 328 otherwise they are interpreted as Latin-1.  C<hash> is a precomputed
 329 hash of the key string, or zero if it has not been precomputed.
 330
 331 =cut
 332 */
 333
 334 #define cophh_delete_pvn(cophh, keypv, keylen, hash, flags) \
 335     Perl_refcounted_he_new_pvn(aTHX_ cophh, keypv, keylen, hash, \
 336         (SV *)NULL, flags)
 337
 338 /*
 339 =for apidoc Amx|COPHH *|cophh_delete_pvs|const COPHH *cophh|const char *key|U32 flags
 340
 341 Like L</cophh_delete_pvn>, but takes a literal string instead of a
 342 string/length pair, and no precomputed hash.
 343
 344 =cut
 345 */
 346
 347 #define cophh_delete_pvs(cophh, key, flags) \
 348     Perl_refcounted_he_new_pvn(aTHX_ cophh, STR_WITH_LEN(key), 0, \
 349         (SV *)NULL, flags)
 350
 351 /*
 352 =for apidoc Amx|COPHH *|cophh_delete_pv|const COPHH *cophh|const char *key|U32 hash|U32 flags
 353
 354 Like L</cophh_delete_pvn>, but takes a nul-terminated string instead of
 355 a string/length pair.
 356
 357 =cut
 358 */
 359
 360 #define cophh_delete_pv(cophh, key, hash, flags) \
 361     Perl_refcounted_he_new_pv(aTHX_ cophh, key, hash, (SV *)NULL, flags)
 362
 363 /*
 364 =for apidoc Amx|COPHH *|cophh_delete_sv|const COPHH *cophh|SV *key|U32 hash|U32 flags
 365
 366 Like L</cophh_delete_pvn>, but takes a Perl scalar instead of a
 367 string/length pair.
 368
 369 =cut
 370 */
 371
 372 #define cophh_delete_sv(cophh, key, hash, flags) \
 373     Perl_refcounted_he_new_sv(aTHX_ cophh, key, hash, (SV *)NULL, flags)
 374
 375 #include "mydtrace.h"
 376
 377 struct cop {
 378     BASEOP
 379     /* On LP64 putting this here takes advantage of the fact that BASEOP isn't
 380        an exact multiple of 8 bytes to save structure padding.  */
 381     line_t      cop_line;       /* line # of this command */
 382     /* label for this construct is now stored in cop_hints_hash */
 383 #ifdef USE_ITHREADS
 384     PADOFFSET   cop_stashoff;   /* offset into PL_stashpad, for the
 385                                    package the line was compiled in */
 386     char *      cop_file;       /* file name the following line # is from */
 387 #else
 388     HV *        cop_stash;      /* package line was compiled in */
 389     GV *        cop_filegv;     /* file the following line # is from */
 390 #endif
 391     U32         cop_hints;      /* hints bits from pragmata */
 392     U32         cop_seq;        /* parse sequence number */
 393     /* Beware. mg.c and warnings.pl assume the type of this is STRLEN *:  */
 394     STRLEN *    cop_warnings;   /* lexical warnings bitmask */
 395     /* compile time state of %^H.  See the comment in op.c for how this is
 396        used to recreate a hash to return from caller.  */
 397     COPHH *     cop_hints_hash;
 398 };
 399
 400 #ifdef USE_ITHREADS
 401 #  define CopFILE(c)            ((c)->cop_file)
 402 #  define CopFILEGV(c)          (CopFILE(c) \
 403                                  ? gv_fetchfile(CopFILE(c)) : NULL)
 404
 405 #  ifdef NETWARE
 406 #    define CopFILE_set(c,pv)   ((c)->cop_file = savepv(pv))
 407 #    define CopFILE_setn(c,pv,l)  ((c)->cop_file = savepvn((pv),(l)))
 408 #  else
 409 #    define CopFILE_set(c,pv)   ((c)->cop_file = savesharedpv(pv))
 410 #    define CopFILE_setn(c,pv,l)  ((c)->cop_file = savesharedpvn((pv),(l)))
 411 #  endif
 412
 413 #  define CopFILESV(c)          (CopFILE(c) \
 414                                  ? GvSV(gv_fetchfile(CopFILE(c))) : NULL)
 415 #  define CopFILEAV(c)          (CopFILE(c) \
 416                                  ? GvAV(gv_fetchfile(CopFILE(c))) : NULL)
 417 #  define CopFILEAVx(c)         (assert_(CopFILE(c)) \
 418                                    GvAV(gv_fetchfile(CopFILE(c))))
 419
 420 #  define CopSTASH(c)           PL_stashpad[(c)->cop_stashoff]
 421 #  define CopSTASH_set(c,hv)    ((c)->cop_stashoff = (hv)               \
 422                                     ? alloccopstash(hv)                 \
 423                                     : 0)
 424 #  ifdef NETWARE
 425 #    define CopFILE_free(c) SAVECOPFILE_FREE(c)
 426 #  else
 427 #    define CopFILE_free(c)     (PerlMemShared_free(CopFILE(c)),(CopFILE(c) = NULL))
 428 #  endif
 429 #else
 430 #  define CopFILEGV(c)          ((c)->cop_filegv)
 431 #  define CopFILEGV_set(c,gv)   ((c)->cop_filegv = (GV*)SvREFCNT_inc(gv))
 432 #  define CopFILE_set(c,pv)     CopFILEGV_set((c), gv_fetchfile(pv))
 433 #  define CopFILE_setn(c,pv,l)  CopFILEGV_set((c), gv_fetchfile_flags((pv),(l),0))
 434 #  define CopFILESV(c)          (CopFILEGV(c) ? GvSV(CopFILEGV(c)) : NULL)
 435 #  define CopFILEAV(c)          (CopFILEGV(c) ? GvAV(CopFILEGV(c)) : NULL)
 436 #  ifdef DEBUGGING
 437 #    define CopFILEAVx(c)       (assert(CopFILEGV(c)), GvAV(CopFILEGV(c)))
 438 #  else
 439 #    define CopFILEAVx(c)       (GvAV(CopFILEGV(c)))
 440 # endif
 441 #  define CopFILE(c)            (CopFILEGV(c) \
 442                                     ? GvNAME(CopFILEGV(c))+2 : NULL)
 443 #  define CopSTASH(c)           ((c)->cop_stash)
 444 #  define CopSTASH_set(c,hv)    ((c)->cop_stash = (hv))
 445 #  define CopFILE_free(c)       (SvREFCNT_dec(CopFILEGV(c)),(CopFILEGV(c) = NULL))
 446
 447 #endif /* USE_ITHREADS */
 448
 449 #define CopSTASHPV(c)           (CopSTASH(c) ? HvNAME_get(CopSTASH(c)) : NULL)
 450    /* cop_stash is not refcounted */
 451 #define CopSTASHPV_set(c,pv)    CopSTASH_set((c), gv_stashpv(pv,GV_ADD))
 452 #define CopSTASH_eq(c,hv)       (CopSTASH(c) == (hv))
 453
 454 #define CopHINTHASH_get(c)      ((COPHH*)((c)->cop_hints_hash))
 455 #define CopHINTHASH_set(c,h)    ((c)->cop_hints_hash = (h))
 456
 457 /*
 458 =head1 COP Hint Reading
 459 */
 460
 461 /*
 462 =for apidoc Am|SV *|cop_hints_fetch_pvn|const COP *cop|const char *keypv|STRLEN keylen|U32 hash|U32 flags
 463
 464 Look up the hint entry in the cop C<cop> with the key specified by
 465 C<keypv> and C<keylen>.  If C<flags> has the C<COPHH_KEY_UTF8> bit set,
 466 the key octets are interpreted as UTF-8, otherwise they are interpreted
 467 as Latin-1.  C<hash> is a precomputed hash of the key string, or zero if
 468 it has not been precomputed.  Returns a mortal scalar copy of the value
 469 associated with the key, or C<&PL_sv_placeholder> if there is no value
 470 associated with the key.
 471
 472 =cut
 473 */
 474
 475 #define cop_hints_fetch_pvn(cop, keypv, keylen, hash, flags) \
 476     cophh_fetch_pvn(CopHINTHASH_get(cop), keypv, keylen, hash, flags)
 477
 478 /*
 479 =for apidoc Am|SV *|cop_hints_fetch_pvs|const COP *cop|const char *key|U32 flags
 480
 481 Like L</cop_hints_fetch_pvn>, but takes a literal string instead of a
 482 string/length pair, and no precomputed hash.
 483
 484 =cut
 485 */
 486
 487 #define cop_hints_fetch_pvs(cop, key, flags) \
 488     cophh_fetch_pvs(CopHINTHASH_get(cop), key, flags)
 489
 490 /*
 491 =for apidoc Am|SV *|cop_hints_fetch_pv|const COP *cop|const char *key|U32 hash|U32 flags
 492
 493 Like L</cop_hints_fetch_pvn>, but takes a nul-terminated string instead
 494 of a string/length pair.
 495
 496 =cut
 497 */
 498
 499 #define cop_hints_fetch_pv(cop, key, hash, flags) \
 500     cophh_fetch_pv(CopHINTHASH_get(cop), key, hash, flags)
 501
 502 /*
 503 =for apidoc Am|SV *|cop_hints_fetch_sv|const COP *cop|SV *key|U32 hash|U32 flags
 504
 505 Like L</cop_hints_fetch_pvn>, but takes a Perl scalar instead of a
 506 string/length pair.
 507
 508 =cut
 509 */
 510
 511 #define cop_hints_fetch_sv(cop, key, hash, flags) \
 512     cophh_fetch_sv(CopHINTHASH_get(cop), key, hash, flags)
 513
 514 /*
 515 =for apidoc Am|HV *|cop_hints_2hv|const COP *cop|U32 flags
 516
 517 Generates and returns a standard Perl hash representing the full set of
 518 hint entries in the cop C<cop>.  C<flags> is currently unused and must
 519 be zero.
 520
 521 =cut
 522 */
 523
 524 #define cop_hints_2hv(cop, flags) \
 525     cophh_2hv(CopHINTHASH_get(cop), flags)
 526
 527 #define CopLABEL(c)  Perl_cop_fetch_label(aTHX_ (c), NULL, NULL)
 528 #define CopLABEL_len(c,len)  Perl_cop_fetch_label(aTHX_ (c), len, NULL)
 529 #define CopLABEL_len_flags(c,len,flags)  Perl_cop_fetch_label(aTHX_ (c), len, flags)
 530 #define CopLABEL_alloc(pv)      ((pv)?savepv(pv):NULL)
 531
 532 #define CopSTASH_ne(c,hv)       (!CopSTASH_eq(c,hv))
 533 #define CopLINE(c)              ((c)->cop_line)
 534 #define CopLINE_inc(c)          (++CopLINE(c))
 535 #define CopLINE_dec(c)          (--CopLINE(c))
 536 #define CopLINE_set(c,l)        (CopLINE(c) = (l))
 537
 538 /* OutCopFILE() is CopFILE for output (caller, die, warn, etc.) */
 539 #define OutCopFILE(c) CopFILE(c)
 540
 541 #define CopHINTS_get(c)         ((c)->cop_hints + 0)
 542 #define CopHINTS_set(c, h)      STMT_START {                            \
 543                                     (c)->cop_hints = (h);               \
 544                                 } STMT_END
 545
 546 /*
 547  * Here we have some enormously heavy (or at least ponderous) wizardry.
 548  */
 549
 550 /* subroutine context */
 551 struct block_sub {
 552     OP *        retop;  /* op to execute on exit from sub */
 553     /* Above here is the same for sub, format and eval.  */
 554     CV *        cv;
 555     /* Above here is the same for sub and format.  */
 556     AV *        savearray;
 557     AV *        argarray;
 558     I32         olddepth;
 559     PAD         *oldcomppad;
 560 };
 561
 562
 563 /* format context */
 564 struct block_format {
 565     OP *        retop;  /* op to execute on exit from sub */
 566     /* Above here is the same for sub, format and eval.  */
 567     CV *        cv;
 568     /* Above here is the same for sub and format.  */
 569     GV *        gv;
 570     GV *        dfoutgv;
 571 };
 572
 573 /* base for the next two macros. Don't use directly.
 574  * Note that the refcnt of the cv is incremented twice;  The CX one is
 575  * decremented by LEAVESUB, the other by LEAVE. */
 576
 577 #define PUSHSUB_BASE(cx)                                                \
 578         ENTRY_PROBE(CvNAMED(cv)                                         \
 579                         ? HEK_KEY(CvNAME_HEK(cv))                       \
 580                         : GvENAME(CvGV(cv)),                            \
 581                 CopFILE((const COP *)CvSTART(cv)),                      \
 582                 CopLINE((const COP *)CvSTART(cv)),                      \
 583                 CopSTASHPV((const COP *)CvSTART(cv)));                  \
 584                                                                         \
 585         cx->blk_sub.cv = cv;                                            \
 586         cx->blk_sub.olddepth = CvDEPTH(cv);                             \
 587         cx->cx_type |= (hasargs) ? CXp_HASARGS : 0;                     \
 588         cx->blk_sub.retop = NULL;                                       \
 589         if (!CvDEPTH(cv)) {                                             \
 590             SvREFCNT_inc_simple_void_NN(cv);                            \
 591             SvREFCNT_inc_simple_void_NN(cv);                            \
 592             SAVEFREESV(cv);                                             \
 593         }
 594
 595 #define PUSHSUB_GET_LVALUE_MASK(func) \
 596         /* If the context is indeterminate, then only the lvalue */     \
 597         /* flags that the caller also has are applicable.        */     \
 598         (                                                               \
 599            (PL_op->op_flags & OPf_WANT)                                 \
 600                ? OPpENTERSUB_LVAL_MASK                                  \
 601                : !(PL_op->op_private & OPpENTERSUB_LVAL_MASK)           \
 602                    ? 0 : (U8)func(aTHX)                                 \
 603         )
 604
 605 #define PUSHSUB(cx)                                                     \
 606     {                                                                   \
 607         U8 phlags = PUSHSUB_GET_LVALUE_MASK(Perl_was_lvalue_sub);       \
 608         PUSHSUB_BASE(cx)                                                \
 609         cx->blk_u16 = PL_op->op_private &                               \
 610                           (phlags|OPpDEREF);                            \
 611     }
 612
 613 /* variant for use by OP_DBSTATE, where op_private holds hint bits */
 614 #define PUSHSUB_DB(cx)                                                  \
 615         PUSHSUB_BASE(cx)                                                \
 616         cx->blk_u16 = 0;
 617
 618
 619 #define PUSHFORMAT(cx, retop)                                           \
 620         cx->blk_format.cv = cv;                                         \
 621         cx->blk_format.gv = gv;                                         \
 622         cx->blk_format.retop = (retop);                                 \
 623         cx->blk_format.dfoutgv = PL_defoutgv;                           \
 624         cx->blk_u16 = 0;                                                \
 625         if (!CvDEPTH(cv)) SvREFCNT_inc_simple_void_NN(cv);              \
 626         CvDEPTH(cv)++;                                                  \
 627         SvREFCNT_inc_void(cx->blk_format.dfoutgv)
 628
 629 #define POP_SAVEARRAY()                                         \
 630     STMT_START {                                                        \
 631         SvREFCNT_dec(GvAV(PL_defgv));                                   \
 632         GvAV(PL_defgv) = cx->blk_sub.savearray;                         \
 633     } STMT_END
 634
 635 /* junk in @_ spells trouble when cloning CVs and in pp_caller(), so don't
 636  * leave any (a fast av_clear(ary), basically) */
 637 #define CLEAR_ARGARRAY(ary) \
 638     STMT_START {                                                        \
 639         AvMAX(ary) += AvARRAY(ary) - AvALLOC(ary);                      \
 640         AvARRAY(ary) = AvALLOC(ary);                                    \
 641         AvFILLp(ary) = -1;                                              \
 642     } STMT_END
 643
 644 #define POPSUB(cx,sv)                                                   \
 645     STMT_START {                                                        \
 646         const I32 olddepth = cx->blk_sub.olddepth;                      \
 647         if (!(cx->blk_u16 & CxPOPSUB_DONE)) {                           \
 648         cx->blk_u16 |= CxPOPSUB_DONE;                                   \
 649         RETURN_PROBE(CvNAMED(cx->blk_sub.cv)                            \
 650                         ? HEK_KEY(CvNAME_HEK(cx->blk_sub.cv))           \
 651                         : GvENAME(CvGV(cx->blk_sub.cv)),                \
 652                 CopFILE((COP*)CvSTART((const CV*)cx->blk_sub.cv)),      \
 653                 CopLINE((COP*)CvSTART((const CV*)cx->blk_sub.cv)),      \
 654                 CopSTASHPV((COP*)CvSTART((const CV*)cx->blk_sub.cv)));  \
 655                                                                         \
 656         if (CxHASARGS(cx)) {                                            \
 657             POP_SAVEARRAY();                                            \
 658             /* abandon @_ if it got reified */                          \
 659             if (AvREAL(cx->blk_sub.argarray)) {                         \
 660                 const SSize_t fill = AvFILLp(cx->blk_sub.argarray);     \
 661                 SvREFCNT_dec_NN(cx->blk_sub.argarray);                  \
 662                 cx->blk_sub.argarray = newAV();                         \
 663                 av_extend(cx->blk_sub.argarray, fill);                  \
 664                 AvREIFY_only(cx->blk_sub.argarray);                     \
 665                 CX_CURPAD_SV(cx->blk_sub, 0) = MUTABLE_SV(cx->blk_sub.argarray); \
 666             }                                                           \
 667             else {                                                      \
 668                 CLEAR_ARGARRAY(cx->blk_sub.argarray);                   \
 669             }                                                           \
 670         }                                                               \
 671         }                                                               \
 672         sv = MUTABLE_SV(cx->blk_sub.cv);                                \
 673         LEAVE_SCOPE(PL_scopestack[cx->blk_oldscopesp-1]);               \
 674         if (sv && (CvDEPTH((const CV*)sv) = olddepth))                  \
 675             sv = NULL;                                          \
 676     } STMT_END
 677
 678 #define LEAVESUB(sv)                                                    \
 679     STMT_START {                                                        \
 680         SvREFCNT_dec(sv);                                               \
 681     } STMT_END
 682
 683 #define POPFORMAT(cx)                                                   \
 684     STMT_START {                                                        \
 685         if (!(cx->blk_u16 & CxPOPSUB_DONE)) {                           \
 686         CV * const cv = cx->blk_format.cv;                              \
 687         GV * const dfuot = cx->blk_format.dfoutgv;                      \
 688         cx->blk_u16 |= CxPOPSUB_DONE;                                   \
 689         setdefout(dfuot);                                               \
 690         LEAVE_SCOPE(PL_scopestack[cx->blk_oldscopesp-1]);               \
 691         if (!--CvDEPTH(cv))                                             \
 692             SvREFCNT_dec_NN(cx->blk_format.cv);                         \
 693         SvREFCNT_dec_NN(dfuot);                                         \
 694         }                                                               \
 695     } STMT_END
 696
 697 /* eval context */
 698 struct block_eval {
 699     OP *        retop;  /* op to execute on exit from eval */
 700     /* Above here is the same for sub, format and eval.  */
 701     SV *        old_namesv;
 702     OP *        old_eval_root;
 703     SV *        cur_text;
 704     CV *        cv;
 705     JMPENV *    cur_top_env; /* value of PL_top_env when eval CX created */
 706 };
 707
 708 /* If we ever need more than 512 op types, change the shift from 7.
 709    blku_gimme is actually also only 2 bits, so could be merged with something.
 710 */
 711
 712 #define CxOLD_IN_EVAL(cx)       (((cx)->blk_u16) & 0x7F)
 713 #define CxOLD_OP_TYPE(cx)       (((cx)->blk_u16) >> 7)
 714
 715 #define PUSHEVAL(cx,n)                                                  \
 716     STMT_START {                                                        \
 717         assert(!(PL_in_eval & ~0x7F));                                  \
 718         assert(!(PL_op->op_type & ~0x1FF));                             \
 719         cx->blk_u16 = (PL_in_eval & 0x7F) | ((U16)PL_op->op_type << 7); \
 720         cx->blk_eval.old_namesv = (n ? newSVpv(n,0) : NULL);            \
 721         cx->blk_eval.old_eval_root = PL_eval_root;                      \
 722         cx->blk_eval.cur_text = PL_parser ? PL_parser->linestr : NULL;  \
 723         cx->blk_eval.cv = NULL; /* set by doeval(), as applicable */    \
 724         cx->blk_eval.retop = NULL;                                      \
 725         cx->blk_eval.cur_top_env = PL_top_env;                          \
 726     } STMT_END
 727
 728 #define POPEVAL(cx)                                                     \
 729     STMT_START {                                                        \
 730         PL_in_eval = CxOLD_IN_EVAL(cx);                                 \
 731         optype = CxOLD_OP_TYPE(cx);                                     \
 732         PL_eval_root = cx->blk_eval.old_eval_root;                      \
 733         if (cx->blk_eval.cur_text && SvSCREAM(cx->blk_eval.cur_text))   \
 734             SvREFCNT_dec_NN(cx->blk_eval.cur_text);                     \
 735         if (cx->blk_eval.old_namesv)                                    \
 736             sv_2mortal(cx->blk_eval.old_namesv);                        \
 737     } STMT_END
 738
 739 /* loop context */
 740 struct block_loop {
 741     I32         resetsp;
 742     LOOP *      my_op;  /* My op, that contains redo, next and last ops.  */
 743     union {     /* different ways of locating the iteration variable */
 744         SV      **svp;
 745         GV      *gv;
 746         PAD     *oldcomppad; /* only used in ITHREADS */
 747     } itervar_u;
 748     union {
 749         struct { /* valid if type is LOOP_FOR or LOOP_PLAIN (but {NULL,0})*/
 750             AV * ary; /* use the stack if this is NULL */
 751             IV ix;
 752         } ary;
 753         struct { /* valid if type is LOOP_LAZYIV */
 754             IV cur;
 755             IV end;
 756         } lazyiv;
 757         struct { /* valid if type if LOOP_LAZYSV */
 758             SV * cur;
 759             SV * end; /* maxiumum value (or minimum in reverse) */
 760         } lazysv;
 761     } state_u;
 762 };
 763
 764 #ifdef USE_ITHREADS
 765 #  define CxITERVAR_PADSV(c) \
 766         &CX_CURPAD_SV( (c)->blk_loop.itervar_u, (c)->blk_loop.my_op->op_targ)
 767 #else
 768 #  define CxITERVAR_PADSV(c) ((c)->blk_loop.itervar_u.svp)
 769 #endif
 770
 771 #define CxITERVAR(c)                                                    \
 772         ((c)->blk_loop.itervar_u.oldcomppad                             \
 773          ? (CxPADLOOP(c)                                                \
 774             ? CxITERVAR_PADSV(c)                                        \
 775             : isGV((c)->blk_loop.itervar_u.gv)                          \
 776                 ? &GvSV((c)->blk_loop.itervar_u.gv)                     \
 777                 : (SV **)&(c)->blk_loop.itervar_u.gv)                   \
 778          : (SV**)NULL)
 779
 780 #define CxLABEL(c)      (0 + CopLABEL((c)->blk_oldcop))
 781 #define CxLABEL_len(c,len)      (0 + CopLABEL_len((c)->blk_oldcop, len))
 782 #define CxLABEL_len_flags(c,len,flags)  (0 + CopLABEL_len_flags((c)->blk_oldcop, len, flags))
 783 #define CxHASARGS(c)    (((c)->cx_type & CXp_HASARGS) == CXp_HASARGS)
 784 #define CxLVAL(c)       (0 + ((c)->blk_u16 & 0xff))
 785 /* POPSUB has already been performed on this context frame */
 786 #define CxPOPSUB_DONE 0x100
 787
 788
 789 #define PUSHLOOP_PLAIN(cx, s)                                           \
 790         cx->blk_loop.resetsp = s - PL_stack_base;                       \
 791         cx->blk_loop.my_op = cLOOP;                                     \
 792         cx->blk_loop.state_u.ary.ary = NULL;                            \
 793         cx->blk_loop.state_u.ary.ix = 0;                                \
 794         cx->blk_loop.itervar_u.svp = NULL;
 795
 796 #define PUSHLOOP_FOR(cx, ivar, s)                                       \
 797         cx->blk_loop.resetsp = s - PL_stack_base;                       \
 798         cx->blk_loop.my_op = cLOOP;                                     \
 799         cx->blk_loop.state_u.ary.ary = NULL;                            \
 800         cx->blk_loop.state_u.ary.ix = 0;                                \
 801         cx->blk_loop.itervar_u.svp = (SV**)(ivar);
 802
 803 #define POPLOOP(cx)                                                     \
 804         if (CxTYPE(cx) == CXt_LOOP_LAZYSV) {                            \
 805             SvREFCNT_dec_NN(cx->blk_loop.state_u.lazysv.cur);           \
 806             SvREFCNT_dec_NN(cx->blk_loop.state_u.lazysv.end);           \
 807         }                                                               \
 808         if (CxTYPE(cx) == CXt_LOOP_FOR)                                 \
 809             SvREFCNT_dec(cx->blk_loop.state_u.ary.ary);
 810
 811 /* given/when context */
 812 struct block_givwhen {
 813         OP *leave_op;
 814 };
 815
 816 #define PUSHGIVEN(cx)                                                   \
 817         cx->blk_givwhen.leave_op = cLOGOP->op_other;
 818
 819 #define PUSHWHEN PUSHGIVEN
 820
 821 /* context common to subroutines, evals and loops */
 822 struct block {
 823     U8          blku_type;      /* what kind of context this is */
 824     U8          blku_gimme;     /* is this block running in list context? */
 825     U16         blku_u16;       /* used by block_sub and block_eval (so far) */
 826     I32         blku_oldsp;     /* stack pointer to copy stuff down to */
 827     COP *       blku_oldcop;    /* old curcop pointer */
 828     I32         blku_oldmarksp; /* mark stack index */
 829     I32         blku_oldscopesp;        /* scope stack index */
 830     PMOP *      blku_oldpm;     /* values of pattern match vars */
 831
 832     union {
 833         struct block_sub        blku_sub;
 834         struct block_format     blku_format;
 835         struct block_eval       blku_eval;
 836         struct block_loop       blku_loop;
 837         struct block_givwhen    blku_givwhen;
 838     } blk_u;
 839 };
 840 #define blk_oldsp       cx_u.cx_blk.blku_oldsp
 841 #define blk_oldcop      cx_u.cx_blk.blku_oldcop
 842 #define blk_oldmarksp   cx_u.cx_blk.blku_oldmarksp
 843 #define blk_oldscopesp  cx_u.cx_blk.blku_oldscopesp
 844 #define blk_oldpm       cx_u.cx_blk.blku_oldpm
 845 #define blk_gimme       cx_u.cx_blk.blku_gimme
 846 #define blk_u16         cx_u.cx_blk.blku_u16
 847 #define blk_sub         cx_u.cx_blk.blk_u.blku_sub
 848 #define blk_format      cx_u.cx_blk.blk_u.blku_format
 849 #define blk_eval        cx_u.cx_blk.blk_u.blku_eval
 850 #define blk_loop        cx_u.cx_blk.blk_u.blku_loop
 851 #define blk_givwhen     cx_u.cx_blk.blk_u.blku_givwhen
 852
 853 #define DEBUG_CX(action)                                                \
 854     DEBUG_l(                                                            \
 855         Perl_deb(aTHX_ "CX %ld %s %s (scope %ld,%ld) at %s:%d\n",       \
 856                     (long)cxstack_ix,                                   \
 857                     action,                                             \
 858                     PL_block_type[CxTYPE(&cxstack[cxstack_ix])],        \
 859                     (long)PL_scopestack_ix,                             \
 860                     (long)(cxstack[cxstack_ix].blk_oldscopesp),         \
 861                     __FILE__, __LINE__));
 862
 863 /* Enter a block. */
 864 #define PUSHBLOCK(cx,t,sp) CXINC, cx = &cxstack[cxstack_ix],            \
 865         cx->cx_type             = t,                                    \
 866         cx->blk_oldsp           = sp - PL_stack_base,                   \
 867         cx->blk_oldcop          = PL_curcop,                            \
 868         cx->blk_oldmarksp       = PL_markstack_ptr - PL_markstack,      \
 869         cx->blk_oldscopesp      = PL_scopestack_ix,                     \
 870         cx->blk_oldpm           = PL_curpm,                             \
 871         cx->blk_gimme           = (U8)gimme;                            \
 872         DEBUG_CX("PUSH");
 873
 874 /* Exit a block (RETURN and LAST). */
 875 #define POPBLOCK(cx,pm)                                                 \
 876         DEBUG_CX("POP");                                                \
 877         cx = &cxstack[cxstack_ix--],                                    \
 878         newsp            = PL_stack_base + cx->blk_oldsp,               \
 879         PL_curcop        = cx->blk_oldcop,                              \
 880         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
 881         PL_scopestack_ix = cx->blk_oldscopesp,                          \
 882         pm               = cx->blk_oldpm,                               \
 883         gimme            = cx->blk_gimme;
 884
 885 /* Continue a block elsewhere (NEXT and REDO). */
 886 #define TOPBLOCK(cx)                                                    \
 887         DEBUG_CX("TOP");                                                \
 888         cx  = &cxstack[cxstack_ix],                                     \
 889         PL_stack_sp      = PL_stack_base + cx->blk_oldsp,               \
 890         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
 891         PL_scopestack_ix = cx->blk_oldscopesp,                          \
 892         PL_curpm         = cx->blk_oldpm;
 893
 894 /* substitution context */
 895 struct subst {
 896     U8          sbu_type;       /* what kind of context this is */
 897     U8          sbu_rflags;
 898     U16         sbu_rxtainted;  /* matches struct block */
 899     I32         sbu_oldsave;
 900     SSize_t     sbu_iters;
 901     SSize_t     sbu_maxiters;
 902     char *      sbu_orig;
 903     SV *        sbu_dstr;
 904     SV *        sbu_targ;
 905     char *      sbu_s;
 906     char *      sbu_m;
 907     char *      sbu_strend;
 908     void *      sbu_rxres;
 909     REGEXP *    sbu_rx;
 910 };
 911 #define sb_iters        cx_u.cx_subst.sbu_iters
 912 #define sb_maxiters     cx_u.cx_subst.sbu_maxiters
 913 #define sb_rflags       cx_u.cx_subst.sbu_rflags
 914 #define sb_oldsave      cx_u.cx_subst.sbu_oldsave
 915 #define sb_rxtainted    cx_u.cx_subst.sbu_rxtainted
 916 #define sb_orig         cx_u.cx_subst.sbu_orig
 917 #define sb_dstr         cx_u.cx_subst.sbu_dstr
 918 #define sb_targ         cx_u.cx_subst.sbu_targ
 919 #define sb_s            cx_u.cx_subst.sbu_s
 920 #define sb_m            cx_u.cx_subst.sbu_m
 921 #define sb_strend       cx_u.cx_subst.sbu_strend
 922 #define sb_rxres        cx_u.cx_subst.sbu_rxres
 923 #define sb_rx           cx_u.cx_subst.sbu_rx
 924
 925 #ifdef PERL_CORE
 926 #  define PUSHSUBST(cx) CXINC, cx = &cxstack[cxstack_ix],               \
 927         cx->sb_iters            = iters,                                \
 928         cx->sb_maxiters         = maxiters,                             \
 929         cx->sb_rflags           = r_flags,                              \
 930         cx->sb_oldsave          = oldsave,                              \
 931         cx->sb_rxtainted        = rxtainted,                            \
 932         cx->sb_orig             = orig,                                 \
 933         cx->sb_dstr             = dstr,                                 \
 934         cx->sb_targ             = targ,                                 \
 935         cx->sb_s                = s,                                    \
 936         cx->sb_m                = m,                                    \
 937         cx->sb_strend           = strend,                               \
 938         cx->sb_rxres            = NULL,                                 \
 939         cx->sb_rx               = rx,                                   \
 940         cx->cx_type             = CXt_SUBST | (once ? CXp_ONCE : 0);    \
 941         rxres_save(&cx->sb_rxres, rx);                                  \
 942         (void)ReREFCNT_inc(rx)
 943
 944 #  define POPSUBST(cx) cx = &cxstack[cxstack_ix--];                     \
 945         rxres_free(&cx->sb_rxres);                                      \
 946         ReREFCNT_dec(cx->sb_rx)
 947 #endif
 948
 949 #define CxONCE(cx)              ((cx)->cx_type & CXp_ONCE)
 950
 951 struct context {
 952     union {
 953         struct block    cx_blk;
 954         struct subst    cx_subst;
 955     } cx_u;
 956 };
 957 #define cx_type cx_u.cx_subst.sbu_type
 958
 959 /* If you re-order these, there is also an array of uppercase names in perl.h
 960    and a static array of context names in pp_ctl.c  */
 961 #define CXTYPEMASK      0xf
 962 #define CXt_NULL        0
 963 #define CXt_WHEN        1
 964 #define CXt_BLOCK       2
 965 /* When micro-optimising :-) keep GIVEN next to the LOOPs, as these 5 share a
 966    jump table in pp_ctl.c
 967    The first 4 don't have a 'case' in at least one switch statement in pp_ctl.c
 968 */
 969 #define CXt_GIVEN       3
 970 /* This is first so that CXt_LOOP_FOR|CXt_LOOP_LAZYIV is CXt_LOOP_LAZYIV */
 971 #define CXt_LOOP_FOR    4
 972 #define CXt_LOOP_PLAIN  5
 973 #define CXt_LOOP_LAZYSV 6
 974 #define CXt_LOOP_LAZYIV 7
 975 #define CXt_SUB         8
 976 #define CXt_FORMAT      9
 977 #define CXt_EVAL       10
 978 #define CXt_SUBST      11
 979 /* SUBST doesn't feature in all switch statements.  */
 980
 981 /* private flags for CXt_SUB and CXt_NULL
 982    However, this is checked in many places which do not check the type, so
 983    this bit needs to be kept clear for most everything else. For reasons I
 984    haven't investigated, it can coexist with CXp_FOR_DEF */
 985 #define CXp_MULTICALL   0x10    /* part of a multicall (so don't
 986                                    tear down context on exit). */
 987
 988 /* private flags for CXt_SUB and CXt_FORMAT */
 989 #define CXp_HASARGS     0x20
 990 #define CXp_SUB_RE      0x40    /* code called within regex, i.e. (?{}) */
 991 #define CXp_SUB_RE_FAKE 0x80    /* fake sub CX for (?{}) in current scope */
 992
 993 /* private flags for CXt_EVAL */
 994 #define CXp_REAL        0x20    /* truly eval'', not a lookalike */
 995 #define CXp_TRYBLOCK    0x40    /* eval{}, not eval'' or similar */
 996
 997 /* private flags for CXt_LOOP */
 998 #define CXp_FOR_DEF     0x10    /* foreach using $_ */
 999 #define CXp_FOR_LVREF   0x20    /* foreach using \$var */
1000 #define CxPADLOOP(c)    ((c)->blk_loop.my_op->op_targ)
1001
1002 /* private flags for CXt_SUBST */
1003 #define CXp_ONCE        0x10    /* What was sbu_once in struct subst */
1004
1005 #define CxTYPE(c)       ((c)->cx_type & CXTYPEMASK)
1006 #define CxTYPE_is_LOOP(c)       (((c)->cx_type & 0xC) == 0x4)
1007 #define CxMULTICALL(c)  (((c)->cx_type & CXp_MULTICALL)                 \
1008                          == CXp_MULTICALL)
1009 #define CxREALEVAL(c)   (((c)->cx_type & (CXTYPEMASK|CXp_REAL))         \
1010                          == (CXt_EVAL|CXp_REAL))
1011 #define CxTRYBLOCK(c)   (((c)->cx_type & (CXTYPEMASK|CXp_TRYBLOCK))     \
1012                          == (CXt_EVAL|CXp_TRYBLOCK))
1013 #define CxFOREACH(c)    (CxTYPE_is_LOOP(c) && CxTYPE(c) != CXt_LOOP_PLAIN)
1014 #define CxFOREACHDEF(c) ((CxTYPE_is_LOOP(c) && CxTYPE(c) != CXt_LOOP_PLAIN) \
1015                          && ((c)->cx_type & CXp_FOR_DEF))
1016
1017 #define CXINC (cxstack_ix < cxstack_max ? ++cxstack_ix : (cxstack_ix = cxinc()))
1018
1019 /*
1020 =head1 "Gimme" Values
1021 */
1022
1023 /*
1024 =for apidoc AmU||G_SCALAR
1025 Used to indicate scalar context.  See C<L</GIMME_V>>, C<L</GIMME>>, and
1026 L<perlcall>.
1027
1028 =for apidoc AmU||G_ARRAY
1029 Used to indicate list context.  See C<L</GIMME_V>>, C<L</GIMME>> and
1030 L<perlcall>.
1031
1032 =for apidoc AmU||G_VOID
1033 Used to indicate void context.  See C<L</GIMME_V>> and L<perlcall>.
1034
1035 =for apidoc AmU||G_DISCARD
1036 Indicates that arguments returned from a callback should be discarded.  See
1037 L<perlcall>.
1038
1039 =for apidoc AmU||G_EVAL
1040
1041 Used to force a Perl C<eval> wrapper around a callback.  See
1042 L<perlcall>.
1043
1044 =for apidoc AmU||G_NOARGS
1045
1046 Indicates that no arguments are being sent to a callback.  See
1047 L<perlcall>.
1048
1049 =cut
1050 */
1051
1052 #define G_SCALAR        2
1053 #define G_ARRAY         3
1054 #define G_VOID          1
1055 #define G_WANT          3
1056
1057 /* extra flags for Perl_call_* routines */
1058 #define G_DISCARD       4       /* Call FREETMPS.
1059                                    Don't change this without consulting the
1060                                    hash actions codes defined in hv.h */
1061 #define G_EVAL          8       /* Assume eval {} around subroutine call. */
1062 #define G_NOARGS       16       /* Don't construct a @_ array. */
1063 #define G_KEEPERR      32       /* Warn for errors, don't overwrite $@ */
1064 #define G_NODEBUG      64       /* Disable debugging at toplevel.  */
1065 #define G_METHOD      128       /* Calling method. */
1066 #define G_FAKINGEVAL  256       /* Faking an eval context for call_sv or
1067                                    fold_constants. */
1068 #define G_UNDEF_FILL  512       /* Fill the stack with &PL_sv_undef
1069                                    A special case for UNSHIFT in
1070                                    Perl_magic_methcall().  */
1071 #define G_WRITING_TO_STDERR 1024 /* Perl_write_to_stderr() is calling
1072                                     Perl_magic_methcall().  */
1073 #define G_RE_REPARSING 0x800     /* compiling a run-time /(?{..})/ */
1074 #define G_METHOD_NAMED 4096     /* calling named method, eg without :: or ' */
1075
1076 /* flag bits for PL_in_eval */
1077 #define EVAL_NULL       0       /* not in an eval */
1078 #define EVAL_INEVAL     1       /* some enclosing scope is an eval */
1079 #define EVAL_WARNONLY   2       /* used by yywarn() when calling yyerror() */
1080 #define EVAL_KEEPERR    4       /* set by Perl_call_sv if G_KEEPERR */
1081 #define EVAL_INREQUIRE  8       /* The code is being required. */
1082 #define EVAL_RE_REPARSING 0x10  /* eval_sv() called with G_RE_REPARSING */
1083
1084 /* Support for switching (stack and block) contexts.
1085  * This ensures magic doesn't invalidate local stack and cx pointers.
1086  */
1087
1088 #define PERLSI_UNKNOWN          -1
1089 #define PERLSI_UNDEF            0
1090 #define PERLSI_MAIN             1
1091 #define PERLSI_MAGIC            2
1092 #define PERLSI_SORT             3
1093 #define PERLSI_SIGNAL           4
1094 #define PERLSI_OVERLOAD         5
1095 #define PERLSI_DESTROY          6
1096 #define PERLSI_WARNHOOK         7
1097 #define PERLSI_DIEHOOK          8
1098 #define PERLSI_REQUIRE          9
1099 #define PERLSI_MULTICALL       10
1100
1101 struct stackinfo {
1102     AV *                si_stack;       /* stack for current runlevel */
1103     PERL_CONTEXT *      si_cxstack;     /* context stack for runlevel */
1104     struct stackinfo *  si_prev;
1105     struct stackinfo *  si_next;
1106     I32                 si_cxix;        /* current context index */
1107     I32                 si_cxmax;       /* maximum allocated index */
1108     I32                 si_type;        /* type of runlevel */
1109     I32                 si_markoff;     /* offset where markstack begins for us.
1110                                          * currently used only with DEBUGGING,
1111                                          * but not #ifdef-ed for bincompat */
1112 };
1113
1114 typedef struct stackinfo PERL_SI;
1115
1116 #define cxstack         (PL_curstackinfo->si_cxstack)
1117 #define cxstack_ix      (PL_curstackinfo->si_cxix)
1118 #define cxstack_max     (PL_curstackinfo->si_cxmax)
1119
1120 #ifdef DEBUGGING
1121 #  define       SET_MARK_OFFSET \
1122     PL_curstackinfo->si_markoff = PL_markstack_ptr - PL_markstack
1123 #else
1124 #  define       SET_MARK_OFFSET NOOP
1125 #endif
1126
1127 #define PUSHSTACKi(type) \
1128     STMT_START {                                                        \
1129         PERL_SI *next = PL_curstackinfo->si_next;                       \
1130         DEBUG_l({                                                       \
1131             int i = 0; PERL_SI *p = PL_curstackinfo;                    \
1132             while (p) { i++; p = p->si_prev; }                          \
1133             Perl_deb(aTHX_ "push STACKINFO %d at %s:%d\n",              \
1134                          i, __FILE__, __LINE__);})                      \
1135         if (!next) {                                                    \
1136             next = new_stackinfo(32, 2048/sizeof(PERL_CONTEXT) - 1);    \
1137             next->si_prev = PL_curstackinfo;                            \
1138             PL_curstackinfo->si_next = next;                            \
1139         }                                                               \
1140         next->si_type = type;                                           \
1141         next->si_cxix = -1;                                             \
1142         AvFILLp(next->si_stack) = 0;                                    \
1143         SWITCHSTACK(PL_curstack,next->si_stack);                        \
1144         PL_curstackinfo = next;                                         \
1145         SET_MARK_OFFSET;                                                \
1146     } STMT_END
1147
1148 #define PUSHSTACK PUSHSTACKi(PERLSI_UNKNOWN)
1149
1150 /* POPSTACK works with PL_stack_sp, so it may need to be bracketed by
1151  * PUTBACK/SPAGAIN to flush/refresh any local SP that may be active */
1152 #define POPSTACK \
1153     STMT_START {                                                        \
1154         dSP;                                                            \
1155         PERL_SI * const prev = PL_curstackinfo->si_prev;                \
1156         DEBUG_l({                                                       \
1157             int i = -1; PERL_SI *p = PL_curstackinfo;                   \
1158             while (p) { i++; p = p->si_prev; }                          \
1159             Perl_deb(aTHX_ "pop  STACKINFO %d at %s:%d\n",              \
1160                          i, __FILE__, __LINE__);})                      \
1161         if (!prev) {                                                    \
1162             Perl_croak_popstack();                                      \
1163         }                                                               \
1164         SWITCHSTACK(PL_curstack,prev->si_stack);                        \
1165         /* don't free prev here, free them all at the END{} */          \
1166         PL_curstackinfo = prev;                                         \
1167     } STMT_END
1168
1169 #define POPSTACK_TO(s) \
1170     STMT_START {                                                        \
1171         while (PL_curstack != s) {                                      \
1172             dounwind(-1);                                               \
1173             POPSTACK;                                                   \
1174         }                                                               \
1175     } STMT_END
1176
1177 #define IN_PERL_COMPILETIME     (PL_curcop == &PL_compiling)
1178 #define IN_PERL_RUNTIME         (PL_curcop != &PL_compiling)
1179
1180 /*
1181 =head1 Multicall Functions
1182
1183 =for apidoc Ams||dMULTICALL
1184 Declare local variables for a multicall.  See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1185
1186 =for apidoc Ams||PUSH_MULTICALL
1187 Opening bracket for a lightweight callback.
1188 See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1189
1190 =for apidoc Ams||MULTICALL
1191 Make a lightweight callback.  See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1192
1193 =for apidoc Ams||POP_MULTICALL
1194 Closing bracket for a lightweight callback.
1195 See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1196
1197 =cut
1198 */
1199
1200 #define dMULTICALL \
1201     SV **newsp;                 /* set by POPBLOCK */                   \
1202     PERL_CONTEXT *cx;                                                   \
1203     CV *multicall_cv;                                                   \
1204     OP *multicall_cop;                                                  \
1205     bool multicall_oldcatch;                                            \
1206     U8 hasargs = 0              /* used by PUSHSUB */
1207
1208 #define PUSH_MULTICALL(the_cv) \
1209     PUSH_MULTICALL_FLAGS(the_cv, 0)
1210
1211 /* Like PUSH_MULTICALL, but allows you to specify extra flags
1212  * for the CX stack entry (this isn't part of the public API) */
1213
1214 #define PUSH_MULTICALL_FLAGS(the_cv, flags) \
1215     STMT_START {                                                        \
1216         CV * const _nOnclAshIngNamE_ = the_cv;                          \
1217         CV * const cv = _nOnclAshIngNamE_;                              \
1218         PADLIST * const padlist = CvPADLIST(cv);                        \
1219         ENTER;                                                          \
1220         multicall_oldcatch = CATCH_GET;                                 \
1221         SAVETMPS; SAVEVPTR(PL_op);                                      \
1222         CATCH_SET(TRUE);                                                \
1223         PUSHSTACKi(PERLSI_MULTICALL);                                   \
1224         PUSHBLOCK(cx, (CXt_SUB|CXp_MULTICALL|flags), PL_stack_sp);      \
1225         PUSHSUB(cx);                                                    \
1226         if (!(flags & CXp_SUB_RE_FAKE))                                 \
1227             CvDEPTH(cv)++;                                              \
1228         if (CvDEPTH(cv) >= 2) {                                         \
1229             PERL_STACK_OVERFLOW_CHECK();                                \
1230             Perl_pad_push(aTHX_ padlist, CvDEPTH(cv));                  \
1231         }                                                               \
1232         SAVECOMPPAD();                                                  \
1233         PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));                       \
1234         multicall_cv = cv;                                              \
1235         multicall_cop = CvSTART(cv);                                    \
1236     } STMT_END
1237
1238 #define MULTICALL \
1239     STMT_START {                                                        \
1240         PL_op = multicall_cop;                                          \
1241         CALLRUNOPS(aTHX);                                               \
1242     } STMT_END
1243
1244 #define POP_MULTICALL \
1245     STMT_START {                                                        \
1246         cx = &cxstack[cxstack_ix];                                      \
1247         if (! ((CvDEPTH(multicall_cv) = cx->blk_sub.olddepth)) ) {      \
1248                 LEAVESUB(multicall_cv);                                 \
1249         }                                                               \
1250         POPBLOCK(cx,PL_curpm);                                          \
1251         POPSTACK;                                                       \
1252         CATCH_SET(multicall_oldcatch);                                  \
1253         LEAVE;                                                          \
1254         SPAGAIN;                                                        \
1255     } STMT_END
1256
1257 /* Change the CV of an already-pushed MULTICALL CxSUB block.
1258  * (this isn't part of the public API) */
1259
1260 #define CHANGE_MULTICALL_FLAGS(the_cv, flags) \
1261     STMT_START {                                                        \
1262         CV * const _nOnclAshIngNamE_ = the_cv;                          \
1263         CV * const cv = _nOnclAshIngNamE_;                              \
1264         PADLIST * const padlist = CvPADLIST(cv);                        \
1265         cx = &cxstack[cxstack_ix];                                      \
1266         assert(cx->cx_type & CXp_MULTICALL);                            \
1267         if (! ((CvDEPTH(multicall_cv) = cx->blk_sub.olddepth)) ) {      \
1268                 LEAVESUB(multicall_cv);                                 \
1269         }                                                               \
1270         cx->cx_type = (CXt_SUB|CXp_MULTICALL|flags);                    \
1271         PUSHSUB(cx);                                                    \
1272         if (!(flags & CXp_SUB_RE_FAKE))                                 \
1273             CvDEPTH(cv)++;                                              \
1274         if (CvDEPTH(cv) >= 2) {                                         \
1275             PERL_STACK_OVERFLOW_CHECK();                                \
1276             Perl_pad_push(aTHX_ padlist, CvDEPTH(cv));                  \
1277         }                                                               \
1278         SAVECOMPPAD();                                                  \
1279         PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));                       \
1280         multicall_cv = cv;                                              \
1281         multicall_cop = CvSTART(cv);                                    \
1282     } STMT_END
1283 /*
1284  * ex: set ts=8 sts=4 sw=4 et:
1285  */