cop.h

   1 /*    cop.h
   2  *
   3  *    Copyright (c) 1991-2002, Larry Wall
   4  *
   5  *    You may distribute under the terms of either the GNU General Public
   6  *    License or the Artistic License, as specified in the README file.
   7  *
   8  */
   9
  10 struct cop {
  11     BASEOP
  12     char *      cop_label;      /* label for this construct */
  13 #ifdef USE_ITHREADS
  14     char *      cop_stashpv;    /* package line was compiled in */
  15     char *      cop_file;       /* file name the following line # is from */
  16 #else
  17     HV *        cop_stash;      /* package line was compiled in */
  18     GV *        cop_filegv;     /* file the following line # is from */
  19 #endif
  20     U32         cop_seq;        /* parse sequence number */
  21     I32         cop_arybase;    /* array base this line was compiled with */
  22     line_t      cop_line;       /* line # of this command */
  23     SV *        cop_warnings;   /* lexical warnings bitmask */
  24     SV *        cop_io;         /* lexical IO defaults */
  25 };
  26
  27 #define Nullcop Null(COP*)
  28
  29 #ifdef USE_ITHREADS
  30 #  define CopFILE(c)            ((c)->cop_file)
  31 #  define CopFILEGV(c)          (CopFILE(c) \
  32                                  ? gv_fetchfile(CopFILE(c)) : Nullgv)
  33 #  define CopFILE_set(c,pv)     ((c)->cop_file = savesharedpv(pv))
  34 #  define CopFILESV(c)          (CopFILE(c) \
  35                                  ? GvSV(gv_fetchfile(CopFILE(c))) : Nullsv)
  36 #  define CopFILEAV(c)          (CopFILE(c) \
  37                                  ? GvAV(gv_fetchfile(CopFILE(c))) : Nullav)
  38 #  define CopSTASHPV(c)         ((c)->cop_stashpv)
  39 #  define CopSTASHPV_set(c,pv)  ((c)->cop_stashpv = savesharedpv(pv))
  40 #  define CopSTASH(c)           (CopSTASHPV(c) \
  41                                  ? gv_stashpv(CopSTASHPV(c),GV_ADD) : Nullhv)
  42 #  define CopSTASH_set(c,hv)    CopSTASHPV_set(c, (hv) ? HvNAME(hv) : Nullch)
  43 #  define CopSTASH_eq(c,hv)     ((hv)                                   \
  44                                  && (CopSTASHPV(c) == HvNAME(hv)        \
  45                                      || (CopSTASHPV(c) && HvNAME(hv)    \
  46                                          && strEQ(CopSTASHPV(c), HvNAME(hv)))))
  47 #  define CopSTASH_free(c)      PerlMemShared_free(CopSTASHPV(c))
  48 #  define CopFILE_free(c)       (PerlMemShared_free(CopFILE(c)),(CopFILE(c) = Nullch))
  49 #else
  50 #  define CopFILEGV(c)          ((c)->cop_filegv)
  51 #  define CopFILEGV_set(c,gv)   ((c)->cop_filegv = (GV*)SvREFCNT_inc(gv))
  52 #  define CopFILE_set(c,pv)     CopFILEGV_set((c), gv_fetchfile(pv))
  53 #  define CopFILESV(c)          (CopFILEGV(c) ? GvSV(CopFILEGV(c)) : Nullsv)
  54 #  define CopFILEAV(c)          (CopFILEGV(c) ? GvAV(CopFILEGV(c)) : Nullav)
  55 #  define CopFILE(c)            (CopFILESV(c) ? SvPVX(CopFILESV(c)) : Nullch)
  56 #  define CopSTASH(c)           ((c)->cop_stash)
  57 #  define CopSTASH_set(c,hv)    ((c)->cop_stash = (hv))
  58 #  define CopSTASHPV(c)         (CopSTASH(c) ? HvNAME(CopSTASH(c)) : Nullch)
  59    /* cop_stash is not refcounted */
  60 #  define CopSTASHPV_set(c,pv)  CopSTASH_set((c), gv_stashpv(pv,GV_ADD))
  61 #  define CopSTASH_eq(c,hv)     (CopSTASH(c) == (hv))
  62 #  define CopSTASH_free(c)
  63 #  define CopFILE_free(c)       (SvREFCNT_dec(CopFILEGV(c)),(CopFILEGV(c) = Nullgv))
  64
  65 #endif /* USE_ITHREADS */
  66
  67 #define CopSTASH_ne(c,hv)       (!CopSTASH_eq(c,hv))
  68 #define CopLINE(c)              ((c)->cop_line)
  69 #define CopLINE_inc(c)          (++CopLINE(c))
  70 #define CopLINE_dec(c)          (--CopLINE(c))
  71 #define CopLINE_set(c,l)        (CopLINE(c) = (l))
  72
  73 /* OutCopFILE() is CopFILE for output (caller, die, warn, etc.) */
  74 #ifdef MACOS_TRADITIONAL
  75 #  define OutCopFILE(c) MacPerl_MPWFileName(CopFILE(c))
  76 #else
  77 #  define OutCopFILE(c) CopFILE(c)
  78 #endif
  79
  80 /*
  81  * Here we have some enormously heavy (or at least ponderous) wizardry.
  82  */
  83
  84 /* subroutine context */
  85 struct block_sub {
  86     CV *        cv;
  87     GV *        gv;
  88     GV *        dfoutgv;
  89 #ifndef USE_5005THREADS
  90     AV *        savearray;
  91 #endif /* USE_5005THREADS */
  92     AV *        argarray;
  93     U16         olddepth;
  94     U8          hasargs;
  95     U8          lval;           /* XXX merge lval and hasargs? */
  96     SV **       oldcurpad;
  97 };
  98
  99 #define PUSHSUB(cx)                                                     \
 100         cx->blk_sub.cv = cv;                                            \
 101         cx->blk_sub.olddepth = CvDEPTH(cv);                             \
 102         cx->blk_sub.hasargs = hasargs;                                  \
 103         cx->blk_sub.lval = PL_op->op_private &                          \
 104                               (OPpLVAL_INTRO|OPpENTERSUB_INARGS);
 105
 106 #define PUSHFORMAT(cx)                                                  \
 107         cx->blk_sub.cv = cv;                                            \
 108         cx->blk_sub.gv = gv;                                            \
 109         cx->blk_sub.hasargs = 0;                                        \
 110         cx->blk_sub.dfoutgv = PL_defoutgv;                              \
 111         (void)SvREFCNT_inc(cx->blk_sub.dfoutgv)
 112
 113 #ifdef USE_5005THREADS
 114 #  define POP_SAVEARRAY() NOOP
 115 #else
 116 #  define POP_SAVEARRAY()                                               \
 117     STMT_START {                                                        \
 118         SvREFCNT_dec(GvAV(PL_defgv));                                   \
 119         GvAV(PL_defgv) = cx->blk_sub.savearray;                         \
 120     } STMT_END
 121 #endif /* USE_5005THREADS */
 122
 123 /* junk in @_ spells trouble when cloning CVs and in pp_caller(), so don't
 124  * leave any (a fast av_clear(ary), basically) */
 125 #define CLEAR_ARGARRAY(ary) \
 126     STMT_START {                                                        \
 127         AvMAX(ary) += AvARRAY(ary) - AvALLOC(ary);                      \
 128         SvPVX(ary) = (char*)AvALLOC(ary);                               \
 129         AvFILLp(ary) = -1;                                              \
 130     } STMT_END
 131
 132 #define POPSUB(cx,sv)                                                   \
 133     STMT_START {                                                        \
 134         if (cx->blk_sub.hasargs) {                                      \
 135             POP_SAVEARRAY();                                            \
 136             /* abandon @_ if it got reified */                          \
 137             if (AvREAL(cx->blk_sub.argarray)) {                         \
 138                 SSize_t fill = AvFILLp(cx->blk_sub.argarray);           \
 139                 SvREFCNT_dec(cx->blk_sub.argarray);                     \
 140                 cx->blk_sub.argarray = newAV();                         \
 141                 av_extend(cx->blk_sub.argarray, fill);                  \
 142                 AvFLAGS(cx->blk_sub.argarray) = AVf_REIFY;              \
 143                 cx->blk_sub.oldcurpad[0] = (SV*)cx->blk_sub.argarray;   \
 144             }                                                           \
 145             else {                                                      \
 146                 CLEAR_ARGARRAY(cx->blk_sub.argarray);                   \
 147             }                                                           \
 148         }                                                               \
 149         sv = (SV*)cx->blk_sub.cv;                                       \
 150         if (sv && (CvDEPTH((CV*)sv) = cx->blk_sub.olddepth))            \
 151             sv = Nullsv;                                                \
 152     } STMT_END
 153
 154 #define LEAVESUB(sv)                                                    \
 155     STMT_START {                                                        \
 156         if (sv)                                                         \
 157             SvREFCNT_dec(sv);                                           \
 158     } STMT_END
 159
 160 #define POPFORMAT(cx)                                                   \
 161         setdefout(cx->blk_sub.dfoutgv);                                 \
 162         SvREFCNT_dec(cx->blk_sub.dfoutgv);
 163
 164 /* eval context */
 165 struct block_eval {
 166     I32         old_in_eval;
 167     I32         old_op_type;
 168     SV *        old_namesv;
 169     OP *        old_eval_root;
 170     SV *        cur_text;
 171     CV *        cv;
 172 };
 173
 174 #define PUSHEVAL(cx,n,fgv)                                              \
 175     STMT_START {                                                        \
 176         cx->blk_eval.old_in_eval = PL_in_eval;                          \
 177         cx->blk_eval.old_op_type = PL_op->op_type;                      \
 178         cx->blk_eval.old_namesv = (n ? newSVpv(n,0) : Nullsv);          \
 179         cx->blk_eval.old_eval_root = PL_eval_root;                      \
 180         cx->blk_eval.cur_text = PL_linestr;                             \
 181         cx->blk_eval.cv = Nullcv; /* set by doeval(), as applicable */  \
 182     } STMT_END
 183
 184 #define POPEVAL(cx)                                                     \
 185     STMT_START {                                                        \
 186         PL_in_eval = cx->blk_eval.old_in_eval;                          \
 187         optype = cx->blk_eval.old_op_type;                              \
 188         PL_eval_root = cx->blk_eval.old_eval_root;                      \
 189         if (cx->blk_eval.old_namesv)                                    \
 190             sv_2mortal(cx->blk_eval.old_namesv);                        \
 191     } STMT_END
 192
 193 /* loop context */
 194 struct block_loop {
 195     char *      label;
 196     I32         resetsp;
 197     OP *        redo_op;
 198     OP *        next_op;
 199     OP *        last_op;
 200 #ifdef USE_ITHREADS
 201     void *      iterdata;
 202     SV **       oldcurpad;
 203 #else
 204     SV **       itervar;
 205 #endif
 206     SV *        itersave;
 207     SV *        iterlval;
 208     AV *        iterary;
 209     IV          iterix;
 210     IV          itermax;
 211 };
 212
 213 #ifdef USE_ITHREADS
 214 #  define CxITERVAR(c)                                                  \
 215         ((c)->blk_loop.iterdata                                         \
 216          ? (CxPADLOOP(cx)                                               \
 217             ? &((c)->blk_loop.oldcurpad)[INT2PTR(PADOFFSET, (c)->blk_loop.iterdata)] \
 218             : &GvSV((GV*)(c)->blk_loop.iterdata))                       \
 219          : (SV**)NULL)
 220 #  define CX_ITERDATA_SET(cx,idata)                                     \
 221         cx->blk_loop.oldcurpad = PL_curpad;                             \
 222         if ((cx->blk_loop.iterdata = (idata)))                          \
 223             cx->blk_loop.itersave = SvREFCNT_inc(*CxITERVAR(cx));
 224 #else
 225 #  define CxITERVAR(c)          ((c)->blk_loop.itervar)
 226 #  define CX_ITERDATA_SET(cx,ivar)                                      \
 227         if ((cx->blk_loop.itervar = (SV**)(ivar)))                      \
 228             cx->blk_loop.itersave = SvREFCNT_inc(*CxITERVAR(cx));
 229 #endif
 230
 231 #define PUSHLOOP(cx, dat, s)                                            \
 232         cx->blk_loop.label = PL_curcop->cop_label;                      \
 233         cx->blk_loop.resetsp = s - PL_stack_base;                       \
 234         cx->blk_loop.redo_op = cLOOP->op_redoop;                        \
 235         cx->blk_loop.next_op = cLOOP->op_nextop;                        \
 236         cx->blk_loop.last_op = cLOOP->op_lastop;                        \
 237         cx->blk_loop.iterlval = Nullsv;                                 \
 238         cx->blk_loop.iterary = Nullav;                                  \
 239         cx->blk_loop.iterix = -1;                                       \
 240         CX_ITERDATA_SET(cx,dat);
 241
 242 #define POPLOOP(cx)                                                     \
 243         SvREFCNT_dec(cx->blk_loop.iterlval);                            \
 244         if (CxITERVAR(cx)) {                                            \
 245             SV **s_v_p = CxITERVAR(cx);                                 \
 246             sv_2mortal(*s_v_p);                                         \
 247             *s_v_p = cx->blk_loop.itersave;                             \
 248         }                                                               \
 249         if (cx->blk_loop.iterary && cx->blk_loop.iterary != PL_curstack)\
 250             SvREFCNT_dec(cx->blk_loop.iterary);
 251
 252 /* context common to subroutines, evals and loops */
 253 struct block {
 254     I32         blku_oldsp;     /* stack pointer to copy stuff down to */
 255     COP *       blku_oldcop;    /* old curcop pointer */
 256     I32         blku_oldretsp;  /* return stack index */
 257     I32         blku_oldmarksp; /* mark stack index */
 258     I32         blku_oldscopesp;        /* scope stack index */
 259     PMOP *      blku_oldpm;     /* values of pattern match vars */
 260     U8          blku_gimme;     /* is this block running in list context? */
 261
 262     union {
 263         struct block_sub        blku_sub;
 264         struct block_eval       blku_eval;
 265         struct block_loop       blku_loop;
 266     } blk_u;
 267 };
 268 #define blk_oldsp       cx_u.cx_blk.blku_oldsp
 269 #define blk_oldcop      cx_u.cx_blk.blku_oldcop
 270 #define blk_oldretsp    cx_u.cx_blk.blku_oldretsp
 271 #define blk_oldmarksp   cx_u.cx_blk.blku_oldmarksp
 272 #define blk_oldscopesp  cx_u.cx_blk.blku_oldscopesp
 273 #define blk_oldpm       cx_u.cx_blk.blku_oldpm
 274 #define blk_gimme       cx_u.cx_blk.blku_gimme
 275 #define blk_sub         cx_u.cx_blk.blk_u.blku_sub
 276 #define blk_eval        cx_u.cx_blk.blk_u.blku_eval
 277 #define blk_loop        cx_u.cx_blk.blk_u.blku_loop
 278
 279 /* Enter a block. */
 280 #define PUSHBLOCK(cx,t,sp) CXINC, cx = &cxstack[cxstack_ix],            \
 281         cx->cx_type             = t,                                    \
 282         cx->blk_oldsp           = sp - PL_stack_base,                   \
 283         cx->blk_oldcop          = PL_curcop,                            \
 284         cx->blk_oldmarksp       = PL_markstack_ptr - PL_markstack,      \
 285         cx->blk_oldscopesp      = PL_scopestack_ix,                     \
 286         cx->blk_oldretsp        = PL_retstack_ix,                       \
 287         cx->blk_oldpm           = PL_curpm,                             \
 288         cx->blk_gimme           = gimme;                                \
 289         DEBUG_l( PerlIO_printf(Perl_debug_log, "Entering block %ld, type %s\n", \
 290                     (long)cxstack_ix, PL_block_type[CxTYPE(cx)]); )
 291
 292 /* Exit a block (RETURN and LAST). */
 293 #define POPBLOCK(cx,pm) cx = &cxstack[cxstack_ix--],                    \
 294         newsp            = PL_stack_base + cx->blk_oldsp,               \
 295         PL_curcop        = cx->blk_oldcop,                              \
 296         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
 297         PL_scopestack_ix = cx->blk_oldscopesp,                          \
 298         PL_retstack_ix   = cx->blk_oldretsp,                            \
 299         pm               = cx->blk_oldpm,                               \
 300         gimme            = cx->blk_gimme;                               \
 301         DEBUG_l( PerlIO_printf(Perl_debug_log, "Leaving block %ld, type %s\n",          \
 302                     (long)cxstack_ix+1,PL_block_type[CxTYPE(cx)]); )
 303
 304 /* Continue a block elsewhere (NEXT and REDO). */
 305 #define TOPBLOCK(cx) cx  = &cxstack[cxstack_ix],                        \
 306         PL_stack_sp      = PL_stack_base + cx->blk_oldsp,               \
 307         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
 308         PL_scopestack_ix = cx->blk_oldscopesp,                          \
 309         PL_retstack_ix   = cx->blk_oldretsp,                            \
 310         PL_curpm         = cx->blk_oldpm
 311
 312 /* substitution context */
 313 struct subst {
 314     I32         sbu_iters;
 315     I32         sbu_maxiters;
 316     I32         sbu_rflags;
 317     I32         sbu_oldsave;
 318     bool        sbu_once;
 319     bool        sbu_rxtainted;
 320     char *      sbu_orig;
 321     SV *        sbu_dstr;
 322     SV *        sbu_targ;
 323     char *      sbu_s;
 324     char *      sbu_m;
 325     char *      sbu_strend;
 326     void *      sbu_rxres;
 327     REGEXP *    sbu_rx;
 328 };
 329 #define sb_iters        cx_u.cx_subst.sbu_iters
 330 #define sb_maxiters     cx_u.cx_subst.sbu_maxiters
 331 #define sb_rflags       cx_u.cx_subst.sbu_rflags
 332 #define sb_oldsave      cx_u.cx_subst.sbu_oldsave
 333 #define sb_once         cx_u.cx_subst.sbu_once
 334 #define sb_rxtainted    cx_u.cx_subst.sbu_rxtainted
 335 #define sb_orig         cx_u.cx_subst.sbu_orig
 336 #define sb_dstr         cx_u.cx_subst.sbu_dstr
 337 #define sb_targ         cx_u.cx_subst.sbu_targ
 338 #define sb_s            cx_u.cx_subst.sbu_s
 339 #define sb_m            cx_u.cx_subst.sbu_m
 340 #define sb_strend       cx_u.cx_subst.sbu_strend
 341 #define sb_rxres        cx_u.cx_subst.sbu_rxres
 342 #define sb_rx           cx_u.cx_subst.sbu_rx
 343
 344 #define PUSHSUBST(cx) CXINC, cx = &cxstack[cxstack_ix],                 \
 345         cx->sb_iters            = iters,                                \
 346         cx->sb_maxiters         = maxiters,                             \
 347         cx->sb_rflags           = r_flags,                              \
 348         cx->sb_oldsave          = oldsave,                              \
 349         cx->sb_once             = once,                                 \
 350         cx->sb_rxtainted        = rxtainted,                            \
 351         cx->sb_orig             = orig,                                 \
 352         cx->sb_dstr             = dstr,                                 \
 353         cx->sb_targ             = targ,                                 \
 354         cx->sb_s                = s,                                    \
 355         cx->sb_m                = m,                                    \
 356         cx->sb_strend           = strend,                               \
 357         cx->sb_rxres            = Null(void*),                          \
 358         cx->sb_rx               = rx,                                   \
 359         cx->cx_type             = CXt_SUBST;                            \
 360         rxres_save(&cx->sb_rxres, rx)
 361
 362 #define POPSUBST(cx) cx = &cxstack[cxstack_ix--];                       \
 363         rxres_free(&cx->sb_rxres)
 364
 365 struct context {
 366     U32         cx_type;        /* what kind of context this is */
 367     union {
 368         struct block    cx_blk;
 369         struct subst    cx_subst;
 370     } cx_u;
 371 };
 372
 373 #define CXTYPEMASK      0xff
 374 #define CXt_NULL        0
 375 #define CXt_SUB         1
 376 #define CXt_EVAL        2
 377 #define CXt_LOOP        3
 378 #define CXt_SUBST       4
 379 #define CXt_BLOCK       5
 380 #define CXt_FORMAT      6
 381
 382 /* private flags for CXt_EVAL */
 383 #define CXp_REAL        0x00000100      /* truly eval'', not a lookalike */
 384 #define CXp_TRYBLOCK    0x00000200      /* eval{}, not eval'' or similar */
 385
 386 #ifdef USE_ITHREADS
 387 /* private flags for CXt_LOOP */
 388 #  define CXp_PADVAR    0x00000100      /* itervar lives on pad, iterdata
 389                                            has pad offset; if not set,
 390                                            iterdata holds GV* */
 391 #  define CxPADLOOP(c)  (((c)->cx_type & (CXt_LOOP|CXp_PADVAR))         \
 392                          == (CXt_LOOP|CXp_PADVAR))
 393 #endif
 394
 395 #define CxTYPE(c)       ((c)->cx_type & CXTYPEMASK)
 396 #define CxREALEVAL(c)   (((c)->cx_type & (CXt_EVAL|CXp_REAL))           \
 397                          == (CXt_EVAL|CXp_REAL))
 398 #define CxTRYBLOCK(c)   (((c)->cx_type & (CXt_EVAL|CXp_TRYBLOCK))       \
 399                          == (CXt_EVAL|CXp_TRYBLOCK))
 400
 401 #define CXINC (cxstack_ix < cxstack_max ? ++cxstack_ix : (cxstack_ix = cxinc()))
 402
 403 /*
 404 =head1 "Gimme" Values
 405 */
 406
 407 /*
 408 =for apidoc AmU||G_SCALAR
 409 Used to indicate scalar context.  See C<GIMME_V>, C<GIMME>, and
 410 L<perlcall>.
 411
 412 =for apidoc AmU||G_ARRAY
 413 Used to indicate list context.  See C<GIMME_V>, C<GIMME> and
 414 L<perlcall>.
 415
 416 =for apidoc AmU||G_VOID
 417 Used to indicate void context.  See C<GIMME_V> and L<perlcall>.
 418
 419 =for apidoc AmU||G_DISCARD
 420 Indicates that arguments returned from a callback should be discarded.  See
 421 L<perlcall>.
 422
 423 =for apidoc AmU||G_EVAL
 424
 425 Used to force a Perl C<eval> wrapper around a callback.  See
 426 L<perlcall>.
 427
 428 =for apidoc AmU||G_NOARGS
 429
 430 Indicates that no arguments are being sent to a callback.  See
 431 L<perlcall>.
 432
 433 =cut
 434 */
 435
 436 #define G_SCALAR        0
 437 #define G_ARRAY         1
 438 #define G_VOID          128     /* skip this bit when adding flags below */
 439
 440 /* extra flags for Perl_call_* routines */
 441 #define G_DISCARD       2       /* Call FREETMPS. */
 442 #define G_EVAL          4       /* Assume eval {} around subroutine call. */
 443 #define G_NOARGS        8       /* Don't construct a @_ array. */
 444 #define G_KEEPERR      16       /* Append errors to $@, don't overwrite it */
 445 #define G_NODEBUG      32       /* Disable debugging at toplevel.  */
 446 #define G_METHOD       64       /* Calling method. */
 447
 448 /* flag bits for PL_in_eval */
 449 #define EVAL_NULL       0       /* not in an eval */
 450 #define EVAL_INEVAL     1       /* some enclosing scope is an eval */
 451 #define EVAL_WARNONLY   2       /* used by yywarn() when calling yyerror() */
 452 #define EVAL_KEEPERR    4       /* set by Perl_call_sv if G_KEEPERR */
 453 #define EVAL_INREQUIRE  8       /* The code is being required. */
 454
 455 /* Support for switching (stack and block) contexts.
 456  * This ensures magic doesn't invalidate local stack and cx pointers.
 457  */
 458
 459 #define PERLSI_UNKNOWN          -1
 460 #define PERLSI_UNDEF            0
 461 #define PERLSI_MAIN             1
 462 #define PERLSI_MAGIC            2
 463 #define PERLSI_SORT             3
 464 #define PERLSI_SIGNAL           4
 465 #define PERLSI_OVERLOAD         5
 466 #define PERLSI_DESTROY          6
 467 #define PERLSI_WARNHOOK         7
 468 #define PERLSI_DIEHOOK          8
 469 #define PERLSI_REQUIRE          9
 470
 471 struct stackinfo {
 472     AV *                si_stack;       /* stack for current runlevel */
 473     PERL_CONTEXT *      si_cxstack;     /* context stack for runlevel */
 474     I32                 si_cxix;        /* current context index */
 475     I32                 si_cxmax;       /* maximum allocated index */
 476     I32                 si_type;        /* type of runlevel */
 477     struct stackinfo *  si_prev;
 478     struct stackinfo *  si_next;
 479     I32                 si_markoff;     /* offset where markstack begins for us.
 480                                          * currently used only with DEBUGGING,
 481                                          * but not #ifdef-ed for bincompat */
 482 };
 483
 484 typedef struct stackinfo PERL_SI;
 485
 486 #define cxstack         (PL_curstackinfo->si_cxstack)
 487 #define cxstack_ix      (PL_curstackinfo->si_cxix)
 488 #define cxstack_max     (PL_curstackinfo->si_cxmax)
 489
 490 #ifdef DEBUGGING
 491 #  define       SET_MARK_OFFSET \
 492     PL_curstackinfo->si_markoff = PL_markstack_ptr - PL_markstack
 493 #else
 494 #  define       SET_MARK_OFFSET NOOP
 495 #endif
 496
 497 #define PUSHSTACKi(type) \
 498     STMT_START {                                                        \
 499         PERL_SI *next = PL_curstackinfo->si_next;                       \
 500         if (!next) {                                                    \
 501             next = new_stackinfo(32, 2048/sizeof(PERL_CONTEXT) - 1);    \
 502             next->si_prev = PL_curstackinfo;                            \
 503             PL_curstackinfo->si_next = next;                            \
 504         }                                                               \
 505         next->si_type = type;                                           \
 506         next->si_cxix = -1;                                             \
 507         AvFILLp(next->si_stack) = 0;                                    \
 508         SWITCHSTACK(PL_curstack,next->si_stack);                        \
 509         PL_curstackinfo = next;                                         \
 510         SET_MARK_OFFSET;                                                \
 511     } STMT_END
 512
 513 #define PUSHSTACK PUSHSTACKi(PERLSI_UNKNOWN)
 514
 515 /* POPSTACK works with PL_stack_sp, so it may need to be bracketed by
 516  * PUTBACK/SPAGAIN to flush/refresh any local SP that may be active */
 517 #define POPSTACK \
 518     STMT_START {                                                        \
 519         dSP;                                                            \
 520         PERL_SI *prev = PL_curstackinfo->si_prev;                       \
 521         if (!prev) {                                                    \
 522             PerlIO_printf(Perl_error_log, "panic: POPSTACK\n");         \
 523             my_exit(1);                                                 \
 524         }                                                               \
 525         SWITCHSTACK(PL_curstack,prev->si_stack);                        \
 526         /* don't free prev here, free them all at the END{} */          \
 527         PL_curstackinfo = prev;                                         \
 528     } STMT_END
 529
 530 #define POPSTACK_TO(s) \
 531     STMT_START {                                                        \
 532         while (PL_curstack != s) {                                      \
 533             dounwind(-1);                                               \
 534             POPSTACK;                                                   \
 535         }                                                               \
 536     } STMT_END