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 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 three ops OP_NEXTSTATE, OP_DBSTATE,
  10  * and OP_SETSTATE that (loosely speaking) are separate statements.
  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 start_env initialized when perl starts, and top_env
  18  * points to this initially, so top_env should always be non-null.
  19  *
  20  * Existence of a non-null top_env->je_prev implies it is valid to call
  21  * longjmp() at that runlevel (we make sure start_env.je_prev is always
  22  * null to ensure this).
  23  *
  24  * je_mustcatch, when set at any runlevel to TRUE, means eval ops must
  25  * establish a local jmpenv to handle exception traps.  Care must be taken
  26  * to restore the previous value of je_mustcatch before exiting the
  27  * stack frame iff JMPENV_PUSH was not called in that stack frame.
  28  * GSAR 97-03-27
  29  */
  30
  31 struct jmpenv {
  32     struct jmpenv *     je_prev;
  33     Sigjmp_buf          je_buf;         /* only for use if !je_throw */
  34     int                 je_ret;         /* last exception thrown */
  35     bool                je_mustcatch;   /* need to call longjmp()? */
  36 };
  37
  38 typedef struct jmpenv JMPENV;
  39
  40 #ifdef OP_IN_REGISTER
  41 #define OP_REG_TO_MEM   PL_opsave = op
  42 #define OP_MEM_TO_REG   op = PL_opsave
  43 #else
  44 #define OP_REG_TO_MEM   NOOP
  45 #define OP_MEM_TO_REG   NOOP
  46 #endif
  47
  48 /*
  49  * How to build the first jmpenv.
  50  *
  51  * top_env needs to be non-zero. It points to an area
  52  * in which longjmp() stuff is stored, as C callstack
  53  * info there at least is thread specific this has to
  54  * be per-thread. Otherwise a 'die' in a thread gives
  55  * that thread the C stack of last thread to do an eval {}!
  56  */
  57
  58 #define JMPENV_BOOTSTRAP \
  59     STMT_START {                                \
  60         Zero(&PL_start_env, 1, JMPENV);         \
  61         PL_start_env.je_ret = -1;               \
  62         PL_start_env.je_mustcatch = TRUE;       \
  63         PL_top_env = &PL_start_env;             \
  64     } STMT_END
  65
  66 /*
  67  *   PERL_FLEXIBLE_EXCEPTIONS
  68  *
  69  * All the flexible exceptions code has been removed.
  70  * See the following threads for details:
  71  *
  72  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/2004-07/msg00378.html
  73  *
  74  * Joshua's original patches (which weren't applied) and discussion:
  75  *
  76  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01396.html
  77  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01489.html
  78  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01491.html
  79  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01608.html
  80  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg02144.html
  81  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg02998.html
  82  *
  83  * Chip's reworked patch and discussion:
  84  *
  85  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1999-03/msg00520.html
  86  *
  87  * The flaw in these patches (which went unnoticed at the time) was
  88  * that they moved some code that could potentially die() out of the
  89  * region protected by the setjmp()s.  This caused exceptions within
  90  * END blocks and such to not be handled by the correct setjmp().
  91  *
  92  * The original patches that introduces flexible exceptions were:
  93  *
  94  *   http://public.activestate.com/cgi-bin/perlbrowse?patch=3386
  95  *   http://public.activestate.com/cgi-bin/perlbrowse?patch=5162
  96  */
  97
  98 #define dJMPENV         JMPENV cur_env
  99
 100 #define JMPENV_PUSH(v) \
 101     STMT_START {                                                        \
 102         DEBUG_l(Perl_deb(aTHX_ "Setting up jumplevel %p, was %p at %s:%d\n",    \
 103                          (void*)&cur_env, (void*)PL_top_env,                    \
 104                          __FILE__, __LINE__));                                  \
 105         cur_env.je_prev = PL_top_env;                                   \
 106         OP_REG_TO_MEM;                                                  \
 107         cur_env.je_ret = PerlProc_setjmp(cur_env.je_buf, SCOPE_SAVES_SIGNAL_MASK);              \
 108         OP_MEM_TO_REG;                                                  \
 109         PL_top_env = &cur_env;                                          \
 110         cur_env.je_mustcatch = FALSE;                                   \
 111         (v) = cur_env.je_ret;                                           \
 112     } STMT_END
 113
 114 #define JMPENV_POP \
 115     STMT_START {                                                        \
 116         DEBUG_l(Perl_deb(aTHX_ "popping jumplevel was %p, now %p at %s:%d\n",   \
 117                          (void*)PL_top_env, (void*)cur_env.je_prev,             \
 118                          __FILE__, __LINE__));                                  \
 119         assert(PL_top_env == &cur_env);                                 \
 120         PL_top_env = cur_env.je_prev;                                   \
 121     } STMT_END
 122
 123 #define JMPENV_JUMP(v) \
 124     STMT_START {                                                \
 125         OP_REG_TO_MEM;                                          \
 126         if (PL_top_env->je_prev)                                \
 127             PerlProc_longjmp(PL_top_env->je_buf, (v));          \
 128         if ((v) == 2)                                           \
 129             PerlProc_exit(STATUS_EXIT);                         \
 130         PerlIO_printf(PerlIO_stderr(), "panic: top_env\n");     \
 131         PerlProc_exit(1);                                       \
 132     } STMT_END
 133
 134 #define CATCH_GET               (PL_top_env->je_mustcatch)
 135 #define CATCH_SET(v)            (PL_top_env->je_mustcatch = (v))
 136
 137
 138 #include "mydtrace.h"
 139
 140 struct cop {
 141     BASEOP
 142     /* On LP64 putting this here takes advantage of the fact that BASEOP isn't
 143        an exact multiple of 8 bytes to save structure padding.  */
 144     line_t      cop_line;       /* line # of this command */
 145     /* label for this construct is now stored in cop_hints_hash */
 146 #ifdef USE_ITHREADS
 147     char *      cop_stashpv;    /* package line was compiled in */
 148     char *      cop_file;       /* file name the following line # is from */
 149 #else
 150     HV *        cop_stash;      /* package line was compiled in */
 151     GV *        cop_filegv;     /* file the following line # is from */
 152 #endif
 153     U32         cop_hints;      /* hints bits from pragmata */
 154     U32         cop_seq;        /* parse sequence number */
 155     /* Beware. mg.c and warnings.pl assume the type of this is STRLEN *:  */
 156     STRLEN *    cop_warnings;   /* lexical warnings bitmask */
 157     /* compile time state of %^H.  See the comment in op.c for how this is
 158        used to recreate a hash to return from caller.  */
 159     struct refcounted_he * cop_hints_hash;
 160 };
 161
 162 #ifdef USE_ITHREADS
 163 #  define CopFILE(c)            ((c)->cop_file)
 164 #  define CopFILEGV(c)          (CopFILE(c) \
 165                                  ? gv_fetchfile(CopFILE(c)) : NULL)
 166
 167 #  ifdef NETWARE
 168 #    define CopFILE_set(c,pv)   ((c)->cop_file = savepv(pv))
 169 #    define CopFILE_setn(c,pv,l)  ((c)->cop_file = savepv((pv),(l)))
 170 #  else
 171 #    define CopFILE_set(c,pv)   ((c)->cop_file = savesharedpv(pv))
 172 #    define CopFILE_setn(c,pv,l)  ((c)->cop_file = savesharedpvn((pv),(l)))
 173 #  endif
 174
 175 #  define CopFILESV(c)          (CopFILE(c) \
 176                                  ? GvSV(gv_fetchfile(CopFILE(c))) : NULL)
 177 #  define CopFILEAV(c)          (CopFILE(c) \
 178                                  ? GvAV(gv_fetchfile(CopFILE(c))) : NULL)
 179 #  ifdef DEBUGGING
 180 #    define CopFILEAVx(c)       (assert(CopFILE(c)), \
 181                                    GvAV(gv_fetchfile(CopFILE(c))))
 182 #  else
 183 #    define CopFILEAVx(c)       (GvAV(gv_fetchfile(CopFILE(c))))
 184 #  endif
 185 #  define CopSTASHPV(c)         ((c)->cop_stashpv)
 186
 187 #  ifdef NETWARE
 188 #    define CopSTASHPV_set(c,pv)        ((c)->cop_stashpv = ((pv) ? savepv(pv) : NULL))
 189 #  else
 190 #    define CopSTASHPV_set(c,pv)        ((c)->cop_stashpv = savesharedpv(pv))
 191 #  endif
 192
 193 #  define CopSTASH(c)           (CopSTASHPV(c) \
 194                                  ? gv_stashpv(CopSTASHPV(c),GV_ADD) : NULL)
 195 #  define CopSTASH_set(c,hv)    CopSTASHPV_set(c, (hv) ? HvNAME_get(hv) : NULL)
 196 #  define CopSTASH_eq(c,hv)     ((hv) && stashpv_hvname_match(c,hv))
 197 #  ifdef NETWARE
 198 #    define CopSTASH_free(c) SAVECOPSTASH_FREE(c)
 199 #    define CopFILE_free(c) SAVECOPFILE_FREE(c)
 200 #  else
 201 #    define CopSTASH_free(c)    PerlMemShared_free(CopSTASHPV(c))
 202 #    define CopFILE_free(c)     (PerlMemShared_free(CopFILE(c)),(CopFILE(c) = NULL))
 203 #  endif
 204 #else
 205 #  define CopFILEGV(c)          ((c)->cop_filegv)
 206 #  define CopFILEGV_set(c,gv)   ((c)->cop_filegv = (GV*)SvREFCNT_inc(gv))
 207 #  define CopFILE_set(c,pv)     CopFILEGV_set((c), gv_fetchfile(pv))
 208 #  define CopFILE_setn(c,pv,l)  CopFILEGV_set((c), gv_fetchfile_flags((pv),(l),0))
 209 #  define CopFILESV(c)          (CopFILEGV(c) ? GvSV(CopFILEGV(c)) : NULL)
 210 #  define CopFILEAV(c)          (CopFILEGV(c) ? GvAV(CopFILEGV(c)) : NULL)
 211 #  ifdef DEBUGGING
 212 #    define CopFILEAVx(c)       (assert(CopFILEGV(c)), GvAV(CopFILEGV(c)))
 213 #  else
 214 #    define CopFILEAVx(c)       (GvAV(CopFILEGV(c)))
 215 # endif
 216 #  define CopFILE(c)            (CopFILEGV(c) && GvSV(CopFILEGV(c)) \
 217                                     ? SvPVX(GvSV(CopFILEGV(c))) : NULL)
 218 #  define CopSTASH(c)           ((c)->cop_stash)
 219 #  define CopSTASH_set(c,hv)    ((c)->cop_stash = (hv))
 220 #  define CopSTASHPV(c)         (CopSTASH(c) ? HvNAME_get(CopSTASH(c)) : NULL)
 221    /* cop_stash is not refcounted */
 222 #  define CopSTASHPV_set(c,pv)  CopSTASH_set((c), gv_stashpv(pv,GV_ADD))
 223 #  define CopSTASH_eq(c,hv)     (CopSTASH(c) == (hv))
 224 #  define CopSTASH_free(c)
 225 #  define CopFILE_free(c)       (SvREFCNT_dec(CopFILEGV(c)),(CopFILEGV(c) = NULL))
 226
 227 #endif /* USE_ITHREADS */
 228 #define CopLABEL(c)  Perl_fetch_cop_label(aTHX_ (c)->cop_hints_hash, NULL, NULL)
 229 #define CopLABEL_alloc(pv)      ((pv)?savepv(pv):NULL)
 230
 231 #define CopSTASH_ne(c,hv)       (!CopSTASH_eq(c,hv))
 232 #define CopLINE(c)              ((c)->cop_line)
 233 #define CopLINE_inc(c)          (++CopLINE(c))
 234 #define CopLINE_dec(c)          (--CopLINE(c))
 235 #define CopLINE_set(c,l)        (CopLINE(c) = (l))
 236
 237 /* OutCopFILE() is CopFILE for output (caller, die, warn, etc.) */
 238 #define OutCopFILE(c) CopFILE(c)
 239
 240 /* If $[ is non-zero, it's stored in cop_hints under the key "$[", and
 241    HINT_ARYBASE is set to indicate this.
 242    Setting it is ineficient due to the need to create 2 mortal SVs, but as
 243    using $[ is highly discouraged, no sane Perl code will be using it.  */
 244 #define CopARYBASE_get(c)       \
 245         ((CopHINTS_get(c) & HINT_ARYBASE)                               \
 246          ? SvIV(Perl_refcounted_he_fetch(aTHX_ (c)->cop_hints_hash, 0,  \
 247                                          "$[", 2, 0, 0))                \
 248          : 0)
 249 #define CopARYBASE_set(c, b) STMT_START { \
 250         if (b || ((c)->cop_hints & HINT_ARYBASE)) {                     \
 251             (c)->cop_hints |= HINT_ARYBASE;                             \
 252             if ((c) == &PL_compiling) {                                 \
 253                 SV *val = newSViv(b);                                   \
 254                 (void)hv_stores(GvHV(PL_hintgv), "$[", val);            \
 255                 mg_set(val);                                            \
 256                 PL_hints |= HINT_ARYBASE;                               \
 257             } else {                                                    \
 258                 (c)->cop_hints_hash                                     \
 259                    = Perl_refcounted_he_new(aTHX_ (c)->cop_hints_hash,  \
 260                                         newSVpvs_flags("$[", SVs_TEMP), \
 261                                         sv_2mortal(newSViv(b)));        \
 262             }                                                           \
 263         }                                                               \
 264     } STMT_END
 265
 266 /* FIXME NATIVE_HINTS if this is changed from op_private (see perl.h)  */
 267 #define CopHINTS_get(c)         ((c)->cop_hints + 0)
 268 #define CopHINTS_set(c, h)      STMT_START {                            \
 269                                     (c)->cop_hints = (h);               \
 270                                 } STMT_END
 271
 272 /*
 273  * Here we have some enormously heavy (or at least ponderous) wizardry.
 274  */
 275
 276 /* subroutine context */
 277 struct block_sub {
 278     OP *        retop;  /* op to execute on exit from sub */
 279     /* Above here is the same for sub, format and eval.  */
 280     CV *        cv;
 281     /* Above here is the same for sub and format.  */
 282     AV *        savearray;
 283     AV *        argarray;
 284     I32         olddepth;
 285     PAD         *oldcomppad;
 286 };
 287
 288
 289 /* format context */
 290 struct block_format {
 291     OP *        retop;  /* op to execute on exit from sub */
 292     /* Above here is the same for sub, format and eval.  */
 293     CV *        cv;
 294     /* Above here is the same for sub and format.  */
 295     GV *        gv;
 296     GV *        dfoutgv;
 297 };
 298
 299 /* base for the next two macros. Don't use directly.
 300  * Note that the refcnt of the cv is incremented twice;  The CX one is
 301  * decremented by LEAVESUB, the other by LEAVE. */
 302
 303 #define PUSHSUB_BASE(cx)                                                \
 304         ENTRY_PROBE(GvENAME(CvGV(cv)),                                  \
 305                 CopFILE((const COP *)CvSTART(cv)),                      \
 306                 CopLINE((const COP *)CvSTART(cv)));                     \
 307                                                                         \
 308         cx->blk_sub.cv = cv;                                            \
 309         cx->blk_sub.olddepth = CvDEPTH(cv);                             \
 310         cx->cx_type |= (hasargs) ? CXp_HASARGS : 0;                     \
 311         cx->blk_sub.retop = NULL;                                       \
 312         if (!CvDEPTH(cv)) {                                             \
 313             SvREFCNT_inc_simple_void_NN(cv);                            \
 314             SvREFCNT_inc_simple_void_NN(cv);                            \
 315             SAVEFREESV(cv);                                             \
 316         }
 317
 318
 319 #define PUSHSUB(cx)                                                     \
 320         PUSHSUB_BASE(cx)                                                \
 321         cx->blk_u16 = PL_op->op_private &                               \
 322                               (OPpLVAL_INTRO|OPpENTERSUB_INARGS);
 323
 324 /* variant for use by OP_DBSTATE, where op_private holds hint bits */
 325 #define PUSHSUB_DB(cx)                                                  \
 326         PUSHSUB_BASE(cx)                                                \
 327         cx->blk_u16 = 0;
 328
 329
 330 #define PUSHFORMAT(cx, retop)                                           \
 331         cx->blk_format.cv = cv;                                         \
 332         cx->blk_format.gv = gv;                                         \
 333         cx->blk_format.retop = (retop);                                 \
 334         cx->blk_format.dfoutgv = PL_defoutgv;                           \
 335         SvREFCNT_inc_void(cx->blk_format.dfoutgv)
 336
 337 #define POP_SAVEARRAY()                                         \
 338     STMT_START {                                                        \
 339         SvREFCNT_dec(GvAV(PL_defgv));                                   \
 340         GvAV(PL_defgv) = cx->blk_sub.savearray;                         \
 341     } STMT_END
 342
 343 /* junk in @_ spells trouble when cloning CVs and in pp_caller(), so don't
 344  * leave any (a fast av_clear(ary), basically) */
 345 #define CLEAR_ARGARRAY(ary) \
 346     STMT_START {                                                        \
 347         AvMAX(ary) += AvARRAY(ary) - AvALLOC(ary);                      \
 348         AvARRAY(ary) = AvALLOC(ary);                                    \
 349         AvFILLp(ary) = -1;                                              \
 350     } STMT_END
 351
 352 #define POPSUB(cx,sv)                                                   \
 353     STMT_START {                                                        \
 354         RETURN_PROBE(GvENAME(CvGV((const CV*)cx->blk_sub.cv)),          \
 355                 CopFILE((COP*)CvSTART((const CV*)cx->blk_sub.cv)),      \
 356                 CopLINE((COP*)CvSTART((const CV*)cx->blk_sub.cv)));     \
 357                                                                         \
 358         if (CxHASARGS(cx)) {                                            \
 359             POP_SAVEARRAY();                                            \
 360             /* abandon @_ if it got reified */                          \
 361             if (AvREAL(cx->blk_sub.argarray)) {                         \
 362                 const SSize_t fill = AvFILLp(cx->blk_sub.argarray);     \
 363                 SvREFCNT_dec(cx->blk_sub.argarray);                     \
 364                 cx->blk_sub.argarray = newAV();                         \
 365                 av_extend(cx->blk_sub.argarray, fill);                  \
 366                 AvREIFY_only(cx->blk_sub.argarray);                     \
 367                 CX_CURPAD_SV(cx->blk_sub, 0) = MUTABLE_SV(cx->blk_sub.argarray); \
 368             }                                                           \
 369             else {                                                      \
 370                 CLEAR_ARGARRAY(cx->blk_sub.argarray);                   \
 371             }                                                           \
 372         }                                                               \
 373         sv = MUTABLE_SV(cx->blk_sub.cv);                                \
 374         if (sv && (CvDEPTH((const CV*)sv) = cx->blk_sub.olddepth))      \
 375             sv = NULL;                                          \
 376     } STMT_END
 377
 378 #define LEAVESUB(sv)                                                    \
 379     STMT_START {                                                        \
 380         if (sv)                                                         \
 381             SvREFCNT_dec(sv);                                           \
 382     } STMT_END
 383
 384 #define POPFORMAT(cx)                                                   \
 385         setdefout(cx->blk_format.dfoutgv);                              \
 386         SvREFCNT_dec(cx->blk_format.dfoutgv);
 387
 388 /* eval context */
 389 struct block_eval {
 390     OP *        retop;  /* op to execute on exit from eval */
 391     /* Above here is the same for sub, format and eval.  */
 392     SV *        old_namesv;
 393     OP *        old_eval_root;
 394     SV *        cur_text;
 395     CV *        cv;
 396     JMPENV *    cur_top_env; /* value of PL_top_env when eval CX created */
 397 };
 398
 399 /* If we ever need more than 512 op types, change the shift from 7.
 400    blku_gimme is actually also only 2 bits, so could be merged with something.
 401 */
 402
 403 #define CxOLD_IN_EVAL(cx)       (((cx)->blk_u16) & 0x7F)
 404 #define CxOLD_OP_TYPE(cx)       (((cx)->blk_u16) >> 7)
 405
 406 #define PUSHEVAL(cx,n)                                                  \
 407     STMT_START {                                                        \
 408         assert(!(PL_in_eval & ~0x7F));                                  \
 409         assert(!(PL_op->op_type & ~0x1FF));                             \
 410         cx->blk_u16 = (PL_in_eval & 0x7F) | ((U16)PL_op->op_type << 7); \
 411         cx->blk_eval.old_namesv = (n ? newSVpv(n,0) : NULL);            \
 412         cx->blk_eval.old_eval_root = PL_eval_root;                      \
 413         cx->blk_eval.cur_text = PL_parser ? PL_parser->linestr : NULL;  \
 414         cx->blk_eval.cv = NULL; /* set by doeval(), as applicable */    \
 415         cx->blk_eval.retop = NULL;                                      \
 416         cx->blk_eval.cur_top_env = PL_top_env;                          \
 417     } STMT_END
 418
 419 #define POPEVAL(cx)                                                     \
 420     STMT_START {                                                        \
 421         PL_in_eval = CxOLD_IN_EVAL(cx);                                 \
 422         optype = CxOLD_OP_TYPE(cx);                                     \
 423         PL_eval_root = cx->blk_eval.old_eval_root;                      \
 424         if (cx->blk_eval.old_namesv)                                    \
 425             sv_2mortal(cx->blk_eval.old_namesv);                        \
 426     } STMT_END
 427
 428 /* loop context */
 429 struct block_loop {
 430     I32         resetsp;
 431     LOOP *      my_op;  /* My op, that contains redo, next and last ops.  */
 432     /* (except for non_ithreads we need to modify next_op in pp_ctl.c, hence
 433         why next_op is conditionally defined below.)  */
 434 #ifdef USE_ITHREADS
 435     PAD         *oldcomppad; /* Also used for the GV, if targoffset is 0 */
 436     /* This is also accesible via cx->blk_loop.my_op->op_targ */
 437     PADOFFSET   targoffset;
 438 #else
 439     OP *        next_op;
 440     SV **       itervar;
 441 #endif
 442     union {
 443         struct { /* valid if type is LOOP_FOR or LOOP_PLAIN (but {NULL,0})*/
 444             AV * ary; /* use the stack if this is NULL */
 445             IV ix;
 446         } ary;
 447         struct { /* valid if type is LOOP_LAZYIV */
 448             IV cur;
 449             IV end;
 450         } lazyiv;
 451         struct { /* valid if type if LOOP_LAZYSV */
 452             SV * cur;
 453             SV * end; /* maxiumum value (or minimum in reverse) */
 454         } lazysv;
 455     } state_u;
 456 };
 457
 458 #ifdef USE_ITHREADS
 459 #  define CxITERVAR(c)                                                  \
 460         ((c)->blk_loop.oldcomppad                                       \
 461          ? (CxPADLOOP(c)                                                \
 462             ? &CX_CURPAD_SV( (c)->blk_loop, (c)->blk_loop.targoffset )  \
 463             : &GvSV((GV*)(c)->blk_loop.oldcomppad))                     \
 464          : (SV**)NULL)
 465 #  define CX_ITERDATA_SET(cx,idata,o)                                   \
 466         if ((cx->blk_loop.targoffset = (o)))                            \
 467             CX_CURPAD_SAVE(cx->blk_loop);                               \
 468         else                                                            \
 469             cx->blk_loop.oldcomppad = (idata);
 470 #else
 471 #  define CxITERVAR(c)          ((c)->blk_loop.itervar)
 472 #  define CX_ITERDATA_SET(cx,ivar,o)                                    \
 473         cx->blk_loop.itervar = (SV**)(ivar);
 474 #endif
 475 #define CxLABEL(c)      (0 + CopLABEL((c)->blk_oldcop))
 476 #define CxHASARGS(c)    (((c)->cx_type & CXp_HASARGS) == CXp_HASARGS)
 477 #define CxLVAL(c)       (0 + (c)->blk_u16)
 478
 479 #ifdef USE_ITHREADS
 480 #  define PUSHLOOP_OP_NEXT              /* No need to do anything.  */
 481 #  define CX_LOOP_NEXTOP_GET(cx)        ((cx)->blk_loop.my_op->op_nextop + 0)
 482 #else
 483 #  define PUSHLOOP_OP_NEXT              cx->blk_loop.next_op = cLOOP->op_nextop
 484 #  define CX_LOOP_NEXTOP_GET(cx)        ((cx)->blk_loop.next_op + 0)
 485 #endif
 486
 487 #define PUSHLOOP_PLAIN(cx, s)                                           \
 488         cx->blk_loop.resetsp = s - PL_stack_base;                       \
 489         cx->blk_loop.my_op = cLOOP;                                     \
 490         PUSHLOOP_OP_NEXT;                                               \
 491         cx->blk_loop.state_u.ary.ary = NULL;                            \
 492         cx->blk_loop.state_u.ary.ix = 0;                                \
 493         CX_ITERDATA_SET(cx, NULL, 0);
 494
 495 #define PUSHLOOP_FOR(cx, dat, s, offset)                                \
 496         cx->blk_loop.resetsp = s - PL_stack_base;                       \
 497         cx->blk_loop.my_op = cLOOP;                                     \
 498         PUSHLOOP_OP_NEXT;                                               \
 499         cx->blk_loop.state_u.ary.ary = NULL;                            \
 500         cx->blk_loop.state_u.ary.ix = 0;                                \
 501         CX_ITERDATA_SET(cx, dat, offset);
 502
 503 #define POPLOOP(cx)                                                     \
 504         if (CxTYPE(cx) == CXt_LOOP_LAZYSV) {                            \
 505             SvREFCNT_dec(cx->blk_loop.state_u.lazysv.cur);              \
 506             SvREFCNT_dec(cx->blk_loop.state_u.lazysv.end);              \
 507         }                                                               \
 508         if (CxTYPE(cx) == CXt_LOOP_FOR)                                 \
 509             SvREFCNT_dec(cx->blk_loop.state_u.ary.ary);
 510
 511 /* given/when context */
 512 struct block_givwhen {
 513         OP *leave_op;
 514 };
 515
 516 #define PUSHGIVEN(cx)                                                   \
 517         cx->blk_givwhen.leave_op = cLOGOP->op_other;
 518
 519 #define PUSHWHEN PUSHGIVEN
 520
 521 /* context common to subroutines, evals and loops */
 522 struct block {
 523     U8          blku_type;      /* what kind of context this is */
 524     U8          blku_gimme;     /* is this block running in list context? */
 525     U16         blku_u16;       /* used by block_sub and block_eval (so far) */
 526     I32         blku_oldsp;     /* stack pointer to copy stuff down to */
 527     COP *       blku_oldcop;    /* old curcop pointer */
 528     I32         blku_oldmarksp; /* mark stack index */
 529     I32         blku_oldscopesp;        /* scope stack index */
 530     PMOP *      blku_oldpm;     /* values of pattern match vars */
 531
 532     union {
 533         struct block_sub        blku_sub;
 534         struct block_format     blku_format;
 535         struct block_eval       blku_eval;
 536         struct block_loop       blku_loop;
 537         struct block_givwhen    blku_givwhen;
 538     } blk_u;
 539 };
 540 #define blk_oldsp       cx_u.cx_blk.blku_oldsp
 541 #define blk_oldcop      cx_u.cx_blk.blku_oldcop
 542 #define blk_oldmarksp   cx_u.cx_blk.blku_oldmarksp
 543 #define blk_oldscopesp  cx_u.cx_blk.blku_oldscopesp
 544 #define blk_oldpm       cx_u.cx_blk.blku_oldpm
 545 #define blk_gimme       cx_u.cx_blk.blku_gimme
 546 #define blk_u16         cx_u.cx_blk.blku_u16
 547 #define blk_sub         cx_u.cx_blk.blk_u.blku_sub
 548 #define blk_format      cx_u.cx_blk.blk_u.blku_format
 549 #define blk_eval        cx_u.cx_blk.blk_u.blku_eval
 550 #define blk_loop        cx_u.cx_blk.blk_u.blku_loop
 551 #define blk_givwhen     cx_u.cx_blk.blk_u.blku_givwhen
 552
 553 /* Enter a block. */
 554 #define PUSHBLOCK(cx,t,sp) CXINC, cx = &cxstack[cxstack_ix],            \
 555         cx->cx_type             = t,                                    \
 556         cx->blk_oldsp           = sp - PL_stack_base,                   \
 557         cx->blk_oldcop          = PL_curcop,                            \
 558         cx->blk_oldmarksp       = PL_markstack_ptr - PL_markstack,      \
 559         cx->blk_oldscopesp      = PL_scopestack_ix,                     \
 560         cx->blk_oldpm           = PL_curpm,                             \
 561         cx->blk_gimme           = (U8)gimme;                            \
 562         DEBUG_l( PerlIO_printf(Perl_debug_log, "Entering block %ld, type %s\n", \
 563                     (long)cxstack_ix, PL_block_type[CxTYPE(cx)]); )
 564
 565 /* Exit a block (RETURN and LAST). */
 566 #define POPBLOCK(cx,pm) cx = &cxstack[cxstack_ix--],                    \
 567         newsp            = PL_stack_base + cx->blk_oldsp,               \
 568         PL_curcop        = cx->blk_oldcop,                              \
 569         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
 570         PL_scopestack_ix = cx->blk_oldscopesp,                          \
 571         pm               = cx->blk_oldpm,                               \
 572         gimme            = cx->blk_gimme;                               \
 573         DEBUG_SCOPE("POPBLOCK");                                        \
 574         DEBUG_l( PerlIO_printf(Perl_debug_log, "Leaving block %ld, type %s\n",          \
 575                     (long)cxstack_ix+1,PL_block_type[CxTYPE(cx)]); )
 576
 577 /* Continue a block elsewhere (NEXT and REDO). */
 578 #define TOPBLOCK(cx) cx  = &cxstack[cxstack_ix],                        \
 579         PL_stack_sp      = PL_stack_base + cx->blk_oldsp,               \
 580         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
 581         PL_scopestack_ix = cx->blk_oldscopesp,                          \
 582         PL_curpm         = cx->blk_oldpm;                               \
 583         DEBUG_SCOPE("TOPBLOCK");
 584
 585 /* substitution context */
 586 struct subst {
 587     U8          sbu_type;       /* what kind of context this is */
 588     U8          sbu_rflags;
 589     U16         sbu_rxtainted;  /* matches struct block */
 590     I32         sbu_iters;
 591     I32         sbu_maxiters;
 592     I32         sbu_oldsave;
 593     char *      sbu_orig;
 594     SV *        sbu_dstr;
 595     SV *        sbu_targ;
 596     char *      sbu_s;
 597     char *      sbu_m;
 598     char *      sbu_strend;
 599     void *      sbu_rxres;
 600     REGEXP *    sbu_rx;
 601 };
 602 #define sb_iters        cx_u.cx_subst.sbu_iters
 603 #define sb_maxiters     cx_u.cx_subst.sbu_maxiters
 604 #define sb_rflags       cx_u.cx_subst.sbu_rflags
 605 #define sb_oldsave      cx_u.cx_subst.sbu_oldsave
 606 #define sb_once         cx_u.cx_subst.sbu_once
 607 #define sb_rxtainted    cx_u.cx_subst.sbu_rxtainted
 608 #define sb_orig         cx_u.cx_subst.sbu_orig
 609 #define sb_dstr         cx_u.cx_subst.sbu_dstr
 610 #define sb_targ         cx_u.cx_subst.sbu_targ
 611 #define sb_s            cx_u.cx_subst.sbu_s
 612 #define sb_m            cx_u.cx_subst.sbu_m
 613 #define sb_strend       cx_u.cx_subst.sbu_strend
 614 #define sb_rxres        cx_u.cx_subst.sbu_rxres
 615 #define sb_rx           cx_u.cx_subst.sbu_rx
 616
 617 #ifdef PERL_CORE
 618 #  define PUSHSUBST(cx) CXINC, cx = &cxstack[cxstack_ix],               \
 619         cx->sb_iters            = iters,                                \
 620         cx->sb_maxiters         = maxiters,                             \
 621         cx->sb_rflags           = r_flags,                              \
 622         cx->sb_oldsave          = oldsave,                              \
 623         cx->sb_rxtainted        = rxtainted,                            \
 624         cx->sb_orig             = orig,                                 \
 625         cx->sb_dstr             = dstr,                                 \
 626         cx->sb_targ             = targ,                                 \
 627         cx->sb_s                = s,                                    \
 628         cx->sb_m                = m,                                    \
 629         cx->sb_strend           = strend,                               \
 630         cx->sb_rxres            = NULL,                                 \
 631         cx->sb_rx               = rx,                                   \
 632         cx->cx_type             = CXt_SUBST | (once ? CXp_ONCE : 0);    \
 633         rxres_save(&cx->sb_rxres, rx);                                  \
 634         (void)ReREFCNT_inc(rx)
 635
 636 #  define POPSUBST(cx) cx = &cxstack[cxstack_ix--];                     \
 637         rxres_free(&cx->sb_rxres);                                      \
 638         ReREFCNT_dec(cx->sb_rx)
 639 #endif
 640
 641 #define CxONCE(cx)              ((cx)->cx_type & CXp_ONCE)
 642
 643 struct context {
 644     union {
 645         struct block    cx_blk;
 646         struct subst    cx_subst;
 647     } cx_u;
 648 };
 649 #define cx_type cx_u.cx_subst.sbu_type
 650
 651 /* If you re-order these, there is also an array of uppercase names in perl.h
 652    and a static array of context names in pp_ctl.c  */
 653 #define CXTYPEMASK      0xf
 654 #define CXt_NULL        0
 655 #define CXt_WHEN        1
 656 #define CXt_BLOCK       2
 657 /* When micro-optimising :-) keep GIVEN next to the LOOPs, as these 5 share a
 658    jump table in pp_ctl.c
 659    The first 4 don't have a 'case' in at least one switch statement in pp_ctl.c
 660 */
 661 #define CXt_GIVEN       3
 662 /* This is first so that CXt_LOOP_FOR|CXt_LOOP_LAZYIV is CXt_LOOP_LAZYIV */
 663 #define CXt_LOOP_FOR    4
 664 #define CXt_LOOP_PLAIN  5
 665 #define CXt_LOOP_LAZYSV 6
 666 #define CXt_LOOP_LAZYIV 7
 667 #define CXt_SUB         8
 668 #define CXt_FORMAT      9
 669 #define CXt_EVAL       10
 670 #define CXt_SUBST      11
 671 /* SUBST doesn't feature in all switch statements.  */
 672
 673 /* private flags for CXt_SUB and CXt_NULL
 674    However, this is checked in many places which do not check the type, so
 675    this bit needs to be kept clear for most everything else. For reasons I
 676    haven't investigated, it can coexist with CXp_FOR_DEF */
 677 #define CXp_MULTICALL   0x10    /* part of a multicall (so don't
 678                                    tear down context on exit). */
 679
 680 /* private flags for CXt_SUB and CXt_FORMAT */
 681 #define CXp_HASARGS     0x20
 682
 683 /* private flags for CXt_EVAL */
 684 #define CXp_REAL        0x20    /* truly eval'', not a lookalike */
 685 #define CXp_TRYBLOCK    0x40    /* eval{}, not eval'' or similar */
 686
 687 /* private flags for CXt_LOOP */
 688 #define CXp_FOR_DEF     0x10    /* foreach using $_ */
 689 #ifdef USE_ITHREADS
 690 #  define CxPADLOOP(c)  ((c)->blk_loop.targoffset)
 691 #endif
 692
 693 /* private flags for CXt_SUBST */
 694 #define CXp_ONCE        0x10    /* What was sbu_once in struct subst */
 695
 696 #define CxTYPE(c)       ((c)->cx_type & CXTYPEMASK)
 697 #define CxTYPE_is_LOOP(c)       (((c)->cx_type & 0xC) == 0x4)
 698 #define CxMULTICALL(c)  (((c)->cx_type & CXp_MULTICALL)                 \
 699                          == CXp_MULTICALL)
 700 #define CxREALEVAL(c)   (((c)->cx_type & (CXTYPEMASK|CXp_REAL))         \
 701                          == (CXt_EVAL|CXp_REAL))
 702 #define CxTRYBLOCK(c)   (((c)->cx_type & (CXTYPEMASK|CXp_TRYBLOCK))     \
 703                          == (CXt_EVAL|CXp_TRYBLOCK))
 704 #define CxFOREACH(c)    (CxTYPE_is_LOOP(c) && CxTYPE(c) != CXt_LOOP_PLAIN)
 705 #define CxFOREACHDEF(c) ((CxTYPE_is_LOOP(c) && CxTYPE(c) != CXt_LOOP_PLAIN) \
 706                          && ((c)->cx_type & CXp_FOR_DEF))
 707
 708 #define CXINC (cxstack_ix < cxstack_max ? ++cxstack_ix : (cxstack_ix = cxinc()))
 709
 710 /*
 711 =head1 "Gimme" Values
 712 */
 713
 714 /*
 715 =for apidoc AmU||G_SCALAR
 716 Used to indicate scalar context.  See C<GIMME_V>, C<GIMME>, and
 717 L<perlcall>.
 718
 719 =for apidoc AmU||G_ARRAY
 720 Used to indicate list context.  See C<GIMME_V>, C<GIMME> and
 721 L<perlcall>.
 722
 723 =for apidoc AmU||G_VOID
 724 Used to indicate void context.  See C<GIMME_V> and L<perlcall>.
 725
 726 =for apidoc AmU||G_DISCARD
 727 Indicates that arguments returned from a callback should be discarded.  See
 728 L<perlcall>.
 729
 730 =for apidoc AmU||G_EVAL
 731
 732 Used to force a Perl C<eval> wrapper around a callback.  See
 733 L<perlcall>.
 734
 735 =for apidoc AmU||G_NOARGS
 736
 737 Indicates that no arguments are being sent to a callback.  See
 738 L<perlcall>.
 739
 740 =cut
 741 */
 742
 743 #define G_SCALAR        2
 744 #define G_ARRAY         3
 745 #define G_VOID          1
 746 #define G_WANT          3
 747
 748 /* extra flags for Perl_call_* routines */
 749 #define G_DISCARD       4       /* Call FREETMPS.
 750                                    Don't change this without consulting the
 751                                    hash actions codes defined in hv.h */
 752 #define G_EVAL          8       /* Assume eval {} around subroutine call. */
 753 #define G_NOARGS       16       /* Don't construct a @_ array. */
 754 #define G_KEEPERR      32       /* Append errors to $@, don't overwrite it */
 755 #define G_NODEBUG      64       /* Disable debugging at toplevel.  */
 756 #define G_METHOD      128       /* Calling method. */
 757 #define G_FAKINGEVAL  256       /* Faking an eval context for call_sv or
 758                                    fold_constants. */
 759
 760 /* flag bits for PL_in_eval */
 761 #define EVAL_NULL       0       /* not in an eval */
 762 #define EVAL_INEVAL     1       /* some enclosing scope is an eval */
 763 #define EVAL_WARNONLY   2       /* used by yywarn() when calling yyerror() */
 764 #define EVAL_KEEPERR    4       /* set by Perl_call_sv if G_KEEPERR */
 765 #define EVAL_INREQUIRE  8       /* The code is being required. */
 766
 767 /* Support for switching (stack and block) contexts.
 768  * This ensures magic doesn't invalidate local stack and cx pointers.
 769  */
 770
 771 #define PERLSI_UNKNOWN          -1
 772 #define PERLSI_UNDEF            0
 773 #define PERLSI_MAIN             1
 774 #define PERLSI_MAGIC            2
 775 #define PERLSI_SORT             3
 776 #define PERLSI_SIGNAL           4
 777 #define PERLSI_OVERLOAD         5
 778 #define PERLSI_DESTROY          6
 779 #define PERLSI_WARNHOOK         7
 780 #define PERLSI_DIEHOOK          8
 781 #define PERLSI_REQUIRE          9
 782
 783 struct stackinfo {
 784     AV *                si_stack;       /* stack for current runlevel */
 785     PERL_CONTEXT *      si_cxstack;     /* context stack for runlevel */
 786     struct stackinfo *  si_prev;
 787     struct stackinfo *  si_next;
 788     I32                 si_cxix;        /* current context index */
 789     I32                 si_cxmax;       /* maximum allocated index */
 790     I32                 si_type;        /* type of runlevel */
 791     I32                 si_markoff;     /* offset where markstack begins for us.
 792                                          * currently used only with DEBUGGING,
 793                                          * but not #ifdef-ed for bincompat */
 794 };
 795
 796 typedef struct stackinfo PERL_SI;
 797
 798 #define cxstack         (PL_curstackinfo->si_cxstack)
 799 #define cxstack_ix      (PL_curstackinfo->si_cxix)
 800 #define cxstack_max     (PL_curstackinfo->si_cxmax)
 801
 802 #ifdef DEBUGGING
 803 #  define       SET_MARK_OFFSET \
 804     PL_curstackinfo->si_markoff = PL_markstack_ptr - PL_markstack
 805 #else
 806 #  define       SET_MARK_OFFSET NOOP
 807 #endif
 808
 809 #define PUSHSTACKi(type) \
 810     STMT_START {                                                        \
 811         PERL_SI *next = PL_curstackinfo->si_next;                       \
 812         if (!next) {                                                    \
 813             next = new_stackinfo(32, 2048/sizeof(PERL_CONTEXT) - 1);    \
 814             next->si_prev = PL_curstackinfo;                            \
 815             PL_curstackinfo->si_next = next;                            \
 816         }                                                               \
 817         next->si_type = type;                                           \
 818         next->si_cxix = -1;                                             \
 819         AvFILLp(next->si_stack) = 0;                                    \
 820         SWITCHSTACK(PL_curstack,next->si_stack);                        \
 821         PL_curstackinfo = next;                                         \
 822         SET_MARK_OFFSET;                                                \
 823     } STMT_END
 824
 825 #define PUSHSTACK PUSHSTACKi(PERLSI_UNKNOWN)
 826
 827 /* POPSTACK works with PL_stack_sp, so it may need to be bracketed by
 828  * PUTBACK/SPAGAIN to flush/refresh any local SP that may be active */
 829 #define POPSTACK \
 830     STMT_START {                                                        \
 831         dSP;                                                            \
 832         PERL_SI * const prev = PL_curstackinfo->si_prev;                \
 833         if (!prev) {                                                    \
 834             PerlIO_printf(Perl_error_log, "panic: POPSTACK\n");         \
 835             my_exit(1);                                                 \
 836         }                                                               \
 837         SWITCHSTACK(PL_curstack,prev->si_stack);                        \
 838         /* don't free prev here, free them all at the END{} */          \
 839         PL_curstackinfo = prev;                                         \
 840     } STMT_END
 841
 842 #define POPSTACK_TO(s) \
 843     STMT_START {                                                        \
 844         while (PL_curstack != s) {                                      \
 845             dounwind(-1);                                               \
 846             POPSTACK;                                                   \
 847         }                                                               \
 848     } STMT_END
 849
 850 #define IN_PERL_COMPILETIME     (PL_curcop == &PL_compiling)
 851 #define IN_PERL_RUNTIME         (PL_curcop != &PL_compiling)
 852
 853 /*
 854 =head1 Multicall Functions
 855
 856 =for apidoc Ams||dMULTICALL
 857 Declare local variables for a multicall. See L<perlcall/Lightweight Callbacks>.
 858
 859 =for apidoc Ams||PUSH_MULTICALL
 860 Opening bracket for a lightweight callback.
 861 See L<perlcall/Lightweight Callbacks>.
 862
 863 =for apidoc Ams||MULTICALL
 864 Make a lightweight callback. See L<perlcall/Lightweight Callbacks>.
 865
 866 =for apidoc Ams||POP_MULTICALL
 867 Closing bracket for a lightweight callback.
 868 See L<perlcall/Lightweight Callbacks>.
 869
 870 =cut
 871 */
 872
 873 #define dMULTICALL \
 874     SV **newsp;                 /* set by POPBLOCK */                   \
 875     PERL_CONTEXT *cx;                                                   \
 876     CV *multicall_cv;                                                   \
 877     OP *multicall_cop;                                                  \
 878     bool multicall_oldcatch;                                            \
 879     U8 hasargs = 0              /* used by PUSHSUB */
 880
 881 #define PUSH_MULTICALL(the_cv) \
 882     STMT_START {                                                        \
 883         CV * const _nOnclAshIngNamE_ = the_cv;                          \
 884         CV * const cv = _nOnclAshIngNamE_;                              \
 885         AV * const padlist = CvPADLIST(cv);                             \
 886         ENTER;                                                          \
 887         multicall_oldcatch = CATCH_GET;                                 \
 888         SAVETMPS; SAVEVPTR(PL_op);                                      \
 889         CATCH_SET(TRUE);                                                \
 890         PUSHSTACKi(PERLSI_SORT);                                        \
 891         PUSHBLOCK(cx, CXt_SUB|CXp_MULTICALL, PL_stack_sp);              \
 892         PUSHSUB(cx);                                                    \
 893         if (++CvDEPTH(cv) >= 2) {                                       \
 894             PERL_STACK_OVERFLOW_CHECK();                                \
 895             Perl_pad_push(aTHX_ padlist, CvDEPTH(cv));                  \
 896         }                                                               \
 897         SAVECOMPPAD();                                                  \
 898         PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));                       \
 899         multicall_cv = cv;                                              \
 900         multicall_cop = CvSTART(cv);                                    \
 901     } STMT_END
 902
 903 #define MULTICALL \
 904     STMT_START {                                                        \
 905         PL_op = multicall_cop;                                          \
 906         CALLRUNOPS(aTHX);                                               \
 907     } STMT_END
 908
 909 #define POP_MULTICALL \
 910     STMT_START {                                                        \
 911         LEAVESUB(multicall_cv);                                         \
 912         CvDEPTH(multicall_cv)--;                                        \
 913         POPBLOCK(cx,PL_curpm);                                          \
 914         POPSTACK;                                                       \
 915         CATCH_SET(multicall_oldcatch);                                  \
 916         LEAVE;                                                          \
 917         SPAGAIN;                                                        \
 918     } STMT_END
 919
 920 /*
 921  * Local variables:
 922  * c-indentation-style: bsd
 923  * c-basic-offset: 4
 924  * indent-tabs-mode: t
 925  * End:
 926  *
 927  * ex: set ts=8 sts=4 sw=4 noet:
 928  */