cop.h

   1 /*    cop.h
   2  *
   3  *    Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
   4  *    2000, 2001, 2002, 2003, 2004, 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 struct cop {
  17     BASEOP
  18     char *      cop_label;      /* label for this construct */
  19 #ifdef USE_ITHREADS
  20     char *      cop_stashpv;    /* package line was compiled in */
  21     char *      cop_file;       /* file name the following line # is from */
  22 #else
  23     HV *        cop_stash;      /* package line was compiled in */
  24     GV *        cop_filegv;     /* file the following line # is from */
  25 #endif
  26     U32         cop_seq;        /* parse sequence number */
  27     I32         cop_arybase;    /* array base this line was compiled with */
  28     line_t      cop_line;       /* line # of this command */
  29     SV *        cop_warnings;   /* lexical warnings bitmask */
  30     SV *        cop_io;         /* lexical IO defaults */
  31 };
  32
  33 #define Nullcop Null(COP*)
  34
  35 #ifdef USE_ITHREADS
  36 #  define CopFILE(c)            ((c)->cop_file)
  37 #  define CopFILEGV(c)          (CopFILE(c) \
  38                                  ? gv_fetchfile(CopFILE(c)) : NULL)
  39
  40 #  ifdef NETWARE
  41 #    define CopFILE_set(c,pv)   ((c)->cop_file = savepv(pv))
  42 #  else
  43 #    define CopFILE_set(c,pv)   ((c)->cop_file = savesharedpv(pv))
  44 #  endif
  45
  46 #  define CopFILESV(c)          (CopFILE(c) \
  47                                  ? GvSV(gv_fetchfile(CopFILE(c))) : NULL)
  48 #  define CopFILEAV(c)          (CopFILE(c) \
  49                                  ? GvAV(gv_fetchfile(CopFILE(c))) : NULL)
  50 #  define CopSTASHPV(c)         ((c)->cop_stashpv)
  51
  52 #  ifdef NETWARE
  53 #    define CopSTASHPV_set(c,pv)        ((c)->cop_stashpv = ((pv) ? savepv(pv) : NULL))
  54 #  else
  55 #    define CopSTASHPV_set(c,pv)        ((c)->cop_stashpv = savesharedpv(pv))
  56 #  endif
  57
  58 #  define CopSTASH(c)           (CopSTASHPV(c) \
  59                                  ? gv_stashpv(CopSTASHPV(c),GV_ADD) : NULL)
  60 #  define CopSTASH_set(c,hv)    CopSTASHPV_set(c, (hv) ? HvNAME_get(hv) : NULL)
  61 #  define CopSTASH_eq(c,hv)     ((hv) && stashpv_hvname_match(c,hv))
  62 #  ifdef NETWARE
  63 #    define CopSTASH_free(c) SAVECOPSTASH_FREE(c)
  64 #    define CopFILE_free(c) SAVECOPFILE_FREE(c)
  65 #  else
  66 #    define CopSTASH_free(c)    PerlMemShared_free(CopSTASHPV(c))
  67 #    define CopFILE_free(c)     (PerlMemShared_free(CopFILE(c)),(CopFILE(c) = NULL))
  68 #  endif
  69 #else
  70 #  define CopFILEGV(c)          ((c)->cop_filegv)
  71 #  define CopFILEGV_set(c,gv)   ((c)->cop_filegv = (GV*)SvREFCNT_inc(gv))
  72 #  define CopFILE_set(c,pv)     CopFILEGV_set((c), gv_fetchfile(pv))
  73 #  define CopFILESV(c)          (CopFILEGV(c) ? GvSV(CopFILEGV(c)) : NULL)
  74 #  define CopFILEAV(c)          (CopFILEGV(c) ? GvAV(CopFILEGV(c)) : NULL)
  75 #  define CopFILE(c)            (CopFILESV(c) ? SvPVX(CopFILESV(c)) : NULL)
  76 #  define CopSTASH(c)           ((c)->cop_stash)
  77 #  define CopSTASH_set(c,hv)    ((c)->cop_stash = (hv))
  78 #  define CopSTASHPV(c)         (CopSTASH(c) ? HvNAME_get(CopSTASH(c)) : NULL)
  79    /* cop_stash is not refcounted */
  80 #  define CopSTASHPV_set(c,pv)  CopSTASH_set((c), gv_stashpv(pv,GV_ADD))
  81 #  define CopSTASH_eq(c,hv)     (CopSTASH(c) == (hv))
  82 #  define CopSTASH_free(c)
  83 #  define CopFILE_free(c)       (SvREFCNT_dec(CopFILEGV(c)),(CopFILEGV(c) = NULL))
  84
  85 #endif /* USE_ITHREADS */
  86
  87 #define CopSTASH_ne(c,hv)       (!CopSTASH_eq(c,hv))
  88 #define CopLINE(c)              ((c)->cop_line)
  89 #define CopLINE_inc(c)          (++CopLINE(c))
  90 #define CopLINE_dec(c)          (--CopLINE(c))
  91 #define CopLINE_set(c,l)        (CopLINE(c) = (l))
  92
  93 /* OutCopFILE() is CopFILE for output (caller, die, warn, etc.) */
  94 #ifdef MACOS_TRADITIONAL
  95 #  define OutCopFILE(c) MacPerl_MPWFileName(CopFILE(c))
  96 #else
  97 #  define OutCopFILE(c) CopFILE(c)
  98 #endif
  99
 100 /*
 101  * Here we have some enormously heavy (or at least ponderous) wizardry.
 102  */
 103
 104 /* subroutine context */
 105 struct block_sub {
 106     CV *        cv;
 107     GV *        gv;
 108     GV *        dfoutgv;
 109 #ifndef USE_5005THREADS
 110     AV *        savearray;
 111 #endif /* USE_5005THREADS */
 112     AV *        argarray;
 113     long        olddepth;
 114     U8          hasargs;
 115     U8          lval;           /* XXX merge lval and hasargs? */
 116     PAD         *oldcomppad;
 117 };
 118
 119 /* base for the next two macros. Don't use directly.
 120  * Note that the refcnt of the cv is incremented twice;  The CX one is
 121  * decremented by LEAVESUB, the other by LEAVE. */
 122
 123 #define PUSHSUB_BASE(cx)                                                \
 124         cx->blk_sub.cv = cv;                                            \
 125         cx->blk_sub.olddepth = CvDEPTH(cv);                             \
 126         cx->blk_sub.hasargs = hasargs;                                  \
 127         if (!CvDEPTH(cv)) {                                             \
 128             SvREFCNT_inc_void(cv);                                      \
 129             SvREFCNT_inc_void(cv);                                      \
 130             SAVEFREESV(cv);                                             \
 131         }
 132
 133
 134 #define PUSHSUB(cx)                                                     \
 135         PUSHSUB_BASE(cx)                                                \
 136         cx->blk_sub.lval = PL_op->op_private &                          \
 137                               (OPpLVAL_INTRO|OPpENTERSUB_INARGS);
 138
 139 /* variant for use by OP_DBSTATE, where op_private holds hint bits */
 140 #define PUSHSUB_DB(cx)                                                  \
 141         PUSHSUB_BASE(cx)                                                \
 142         cx->blk_sub.lval = 0;
 143
 144
 145 #define PUSHFORMAT(cx)                                                  \
 146         cx->blk_sub.cv = cv;                                            \
 147         cx->blk_sub.gv = gv;                                            \
 148         cx->blk_sub.hasargs = 0;                                        \
 149         cx->blk_sub.dfoutgv = PL_defoutgv;                              \
 150         SvREFCNT_inc_void(cx->blk_sub.dfoutgv)
 151
 152 #ifdef USE_5005THREADS
 153 #  define POP_SAVEARRAY() NOOP
 154 #else
 155 #  define POP_SAVEARRAY()                                               \
 156     STMT_START {                                                        \
 157         SvREFCNT_dec(GvAV(PL_defgv));                                   \
 158         GvAV(PL_defgv) = cx->blk_sub.savearray;                         \
 159     } STMT_END
 160 #endif /* USE_5005THREADS */
 161
 162 /* junk in @_ spells trouble when cloning CVs and in pp_caller(), so don't
 163  * leave any (a fast av_clear(ary), basically) */
 164 #define CLEAR_ARGARRAY(ary) \
 165     STMT_START {                                                        \
 166         AvMAX(ary) += AvARRAY(ary) - AvALLOC(ary);                      \
 167         SvPV_set(ary, (char*)AvALLOC(ary));                             \
 168         AvFILLp(ary) = -1;                                              \
 169     } STMT_END
 170
 171 #define POPSUB(cx,sv)                                                   \
 172     STMT_START {                                                        \
 173         if (cx->blk_sub.hasargs) {                                      \
 174             POP_SAVEARRAY();                                            \
 175             /* abandon @_ if it got reified */                          \
 176             if (AvREAL(cx->blk_sub.argarray)) {                         \
 177                 SSize_t fill = AvFILLp(cx->blk_sub.argarray);           \
 178                 SvREFCNT_dec(cx->blk_sub.argarray);                     \
 179                 cx->blk_sub.argarray = newAV();                         \
 180                 av_extend(cx->blk_sub.argarray, fill);                  \
 181                 AvFLAGS(cx->blk_sub.argarray) = AVf_REIFY;              \
 182                 CX_CURPAD_SV(cx->blk_sub, 0) = (SV*)cx->blk_sub.argarray;       \
 183             }                                                           \
 184             else {                                                      \
 185                 CLEAR_ARGARRAY(cx->blk_sub.argarray);                   \
 186             }                                                           \
 187         }                                                               \
 188         sv = (SV*)cx->blk_sub.cv;                                       \
 189         if (sv && (CvDEPTH((CV*)sv) = cx->blk_sub.olddepth))            \
 190             sv = NULL;                                          \
 191     } STMT_END
 192
 193 #define LEAVESUB(sv)                                                    \
 194     STMT_START {                                                        \
 195         if (sv)                                                         \
 196             SvREFCNT_dec(sv);                                           \
 197     } STMT_END
 198
 199 #define POPFORMAT(cx)                                                   \
 200         setdefout(cx->blk_sub.dfoutgv);                                 \
 201         SvREFCNT_dec(cx->blk_sub.dfoutgv);
 202
 203 /* eval context */
 204 struct block_eval {
 205     I32         old_in_eval;
 206     I32         old_op_type;
 207     SV *        old_namesv;
 208     OP *        old_eval_root;
 209     SV *        cur_text;
 210     CV *        cv;
 211 };
 212
 213 #define PUSHEVAL(cx,n,fgv)                                              \
 214     STMT_START {                                                        \
 215         cx->blk_eval.old_in_eval = PL_in_eval;                          \
 216         cx->blk_eval.old_op_type = PL_op->op_type;                      \
 217         cx->blk_eval.old_namesv = (n ? newSVpv(n,0) : NULL);            \
 218         cx->blk_eval.old_eval_root = PL_eval_root;                      \
 219         cx->blk_eval.cur_text = PL_linestr;                             \
 220         cx->blk_eval.cv = Nullcv; /* set by doeval(), as applicable */  \
 221     } STMT_END
 222
 223 #define POPEVAL(cx)                                                     \
 224     STMT_START {                                                        \
 225         PL_in_eval = cx->blk_eval.old_in_eval;                          \
 226         optype = cx->blk_eval.old_op_type;                              \
 227         PL_eval_root = cx->blk_eval.old_eval_root;                      \
 228         if (cx->blk_eval.old_namesv)                                    \
 229             sv_2mortal(cx->blk_eval.old_namesv);                        \
 230     } STMT_END
 231
 232 /* loop context */
 233 struct block_loop {
 234     char *      label;
 235     I32         resetsp;
 236     OP *        redo_op;
 237     OP *        next_op;
 238     OP *        last_op;
 239 #ifdef USE_ITHREADS
 240     void *      iterdata;
 241     PAD         *oldcomppad;
 242 #else
 243     SV **       itervar;
 244 #endif
 245     SV *        itersave;
 246     SV *        iterlval;
 247     AV *        iterary;
 248     IV          iterix;
 249     IV          itermax;
 250 };
 251
 252 #ifdef USE_ITHREADS
 253 #  define CxITERVAR(c)                                                  \
 254         ((c)->blk_loop.iterdata                                         \
 255          ? (CxPADLOOP(cx)                                               \
 256             ? &CX_CURPAD_SV( (c)->blk_loop,                             \
 257                     INT2PTR(PADOFFSET, (c)->blk_loop.iterdata))         \
 258             : &GvSV((GV*)(c)->blk_loop.iterdata))                       \
 259          : (SV**)NULL)
 260 #  define CX_ITERDATA_SET(cx,idata)                                     \
 261         CX_CURPAD_SAVE(cx->blk_loop);                                   \
 262         if ((cx->blk_loop.iterdata = (idata)))                          \
 263             cx->blk_loop.itersave = SvREFCNT_inc(*CxITERVAR(cx));       \
 264         else                                                            \
 265             cx->blk_loop.itersave = NULL;
 266 #else
 267 #  define CxITERVAR(c)          ((c)->blk_loop.itervar)
 268 #  define CX_ITERDATA_SET(cx,ivar)                                      \
 269         if ((cx->blk_loop.itervar = (SV**)(ivar)))                      \
 270             cx->blk_loop.itersave = SvREFCNT_inc(*CxITERVAR(cx));       \
 271         else                                                            \
 272             cx->blk_loop.itersave = NULL;
 273 #endif
 274
 275 #define PUSHLOOP(cx, dat, s)                                            \
 276         cx->blk_loop.label = PL_curcop->cop_label;                      \
 277         cx->blk_loop.resetsp = s - PL_stack_base;                       \
 278         cx->blk_loop.redo_op = cLOOP->op_redoop;                        \
 279         cx->blk_loop.next_op = cLOOP->op_nextop;                        \
 280         cx->blk_loop.last_op = cLOOP->op_lastop;                        \
 281         cx->blk_loop.iterlval = NULL;                                   \
 282         cx->blk_loop.iterary = NULL;                                    \
 283         cx->blk_loop.iterix = -1;                                       \
 284         CX_ITERDATA_SET(cx,dat);
 285
 286 #define POPLOOP(cx)                                                     \
 287         SvREFCNT_dec(cx->blk_loop.iterlval);                            \
 288         if (CxITERVAR(cx)) {                                            \
 289             SV **s_v_p = CxITERVAR(cx);                                 \
 290             sv_2mortal(*s_v_p);                                         \
 291             *s_v_p = cx->blk_loop.itersave;                             \
 292         }                                                               \
 293         if (cx->blk_loop.iterary && cx->blk_loop.iterary != PL_curstack)\
 294             SvREFCNT_dec(cx->blk_loop.iterary);
 295
 296 /* context common to subroutines, evals and loops */
 297 struct block {
 298     I32         blku_oldsp;     /* stack pointer to copy stuff down to */
 299     COP *       blku_oldcop;    /* old curcop pointer */
 300     I32         blku_oldretsp;  /* return stack index */
 301     I32         blku_oldmarksp; /* mark stack index */
 302     I32         blku_oldscopesp;        /* scope stack index */
 303     PMOP *      blku_oldpm;     /* values of pattern match vars */
 304     U8          blku_gimme;     /* is this block running in list context? */
 305
 306     union {
 307         struct block_sub        blku_sub;
 308         struct block_eval       blku_eval;
 309         struct block_loop       blku_loop;
 310     } blk_u;
 311 };
 312 #define blk_oldsp       cx_u.cx_blk.blku_oldsp
 313 #define blk_oldcop      cx_u.cx_blk.blku_oldcop
 314 #define blk_oldretsp    cx_u.cx_blk.blku_oldretsp
 315 #define blk_oldmarksp   cx_u.cx_blk.blku_oldmarksp
 316 #define blk_oldscopesp  cx_u.cx_blk.blku_oldscopesp
 317 #define blk_oldpm       cx_u.cx_blk.blku_oldpm
 318 #define blk_gimme       cx_u.cx_blk.blku_gimme
 319 #define blk_sub         cx_u.cx_blk.blk_u.blku_sub
 320 #define blk_eval        cx_u.cx_blk.blk_u.blku_eval
 321 #define blk_loop        cx_u.cx_blk.blk_u.blku_loop
 322
 323 /* Enter a block. */
 324 #define PUSHBLOCK(cx,t,sp) CXINC, cx = &cxstack[cxstack_ix],            \
 325         cx->cx_type             = t,                                    \
 326         cx->blk_oldsp           = sp - PL_stack_base,                   \
 327         cx->blk_oldcop          = PL_curcop,                            \
 328         cx->blk_oldmarksp       = PL_markstack_ptr - PL_markstack,      \
 329         cx->blk_oldscopesp      = PL_scopestack_ix,                     \
 330         cx->blk_oldretsp        = PL_retstack_ix,                       \
 331         cx->blk_oldpm           = PL_curpm,                             \
 332         cx->blk_gimme           = (U8)gimme;                            \
 333         DEBUG_l( PerlIO_printf(Perl_debug_log, "Entering block %ld, type %s\n", \
 334                     (long)cxstack_ix, PL_block_type[CxTYPE(cx)]); )
 335
 336 /* Exit a block (RETURN and LAST). */
 337 #define POPBLOCK(cx,pm) cx = &cxstack[cxstack_ix--],                    \
 338         newsp            = PL_stack_base + cx->blk_oldsp,               \
 339         PL_curcop        = cx->blk_oldcop,                              \
 340         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
 341         PL_scopestack_ix = cx->blk_oldscopesp,                          \
 342         PL_retstack_ix   = cx->blk_oldretsp,                            \
 343         pm               = cx->blk_oldpm,                               \
 344         gimme            = cx->blk_gimme;                               \
 345         DEBUG_SCOPE("POPBLOCK");                                        \
 346         DEBUG_l( PerlIO_printf(Perl_debug_log, "Leaving block %ld, type %s\n",          \
 347                     (long)cxstack_ix+1,PL_block_type[CxTYPE(cx)]); )
 348
 349 /* Continue a block elsewhere (NEXT and REDO). */
 350 #define TOPBLOCK(cx) cx  = &cxstack[cxstack_ix],                        \
 351         PL_stack_sp      = PL_stack_base + cx->blk_oldsp,               \
 352         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
 353         PL_scopestack_ix = cx->blk_oldscopesp,                          \
 354         PL_retstack_ix   = cx->blk_oldretsp,                            \
 355         PL_curpm         = cx->blk_oldpm;                               \
 356         DEBUG_SCOPE("TOPBLOCK");
 357
 358 /* substitution context */
 359 struct subst {
 360     I32         sbu_iters;
 361     I32         sbu_maxiters;
 362     I32         sbu_rflags;
 363     I32         sbu_oldsave;
 364     bool        sbu_once;
 365     bool        sbu_rxtainted;
 366     char *      sbu_orig;
 367     SV *        sbu_dstr;
 368     SV *        sbu_targ;
 369     char *      sbu_s;
 370     char *      sbu_m;
 371     char *      sbu_strend;
 372     void *      sbu_rxres;
 373     REGEXP *    sbu_rx;
 374 };
 375 #define sb_iters        cx_u.cx_subst.sbu_iters
 376 #define sb_maxiters     cx_u.cx_subst.sbu_maxiters
 377 #define sb_rflags       cx_u.cx_subst.sbu_rflags
 378 #define sb_oldsave      cx_u.cx_subst.sbu_oldsave
 379 #define sb_once         cx_u.cx_subst.sbu_once
 380 #define sb_rxtainted    cx_u.cx_subst.sbu_rxtainted
 381 #define sb_orig         cx_u.cx_subst.sbu_orig
 382 #define sb_dstr         cx_u.cx_subst.sbu_dstr
 383 #define sb_targ         cx_u.cx_subst.sbu_targ
 384 #define sb_s            cx_u.cx_subst.sbu_s
 385 #define sb_m            cx_u.cx_subst.sbu_m
 386 #define sb_strend       cx_u.cx_subst.sbu_strend
 387 #define sb_rxres        cx_u.cx_subst.sbu_rxres
 388 #define sb_rx           cx_u.cx_subst.sbu_rx
 389
 390 #define PUSHSUBST(cx) CXINC, cx = &cxstack[cxstack_ix],                 \
 391         cx->sb_iters            = iters,                                \
 392         cx->sb_maxiters         = maxiters,                             \
 393         cx->sb_rflags           = r_flags,                              \
 394         cx->sb_oldsave          = oldsave,                              \
 395         cx->sb_once             = once,                                 \
 396         cx->sb_rxtainted        = rxtainted,                            \
 397         cx->sb_orig             = orig,                                 \
 398         cx->sb_dstr             = dstr,                                 \
 399         cx->sb_targ             = targ,                                 \
 400         cx->sb_s                = s,                                    \
 401         cx->sb_m                = m,                                    \
 402         cx->sb_strend           = strend,                               \
 403         cx->sb_rxres            = NULL,                                 \
 404         cx->sb_rx               = rx,                                   \
 405         cx->cx_type             = CXt_SUBST;                            \
 406         rxres_save(&cx->sb_rxres, rx)
 407
 408 #define POPSUBST(cx) cx = &cxstack[cxstack_ix--];                       \
 409         rxres_free(&cx->sb_rxres)
 410
 411 struct context {
 412     U32         cx_type;        /* what kind of context this is */
 413     union {
 414         struct block    cx_blk;
 415         struct subst    cx_subst;
 416     } cx_u;
 417 };
 418
 419 #define CXTYPEMASK      0xff
 420 #define CXt_NULL        0
 421 #define CXt_SUB         1
 422 #define CXt_EVAL        2
 423 #define CXt_LOOP        3
 424 #define CXt_SUBST       4
 425 #define CXt_BLOCK       5
 426 #define CXt_FORMAT      6
 427
 428 /* private flags for CXt_SUB and CXt_NULL */
 429 #define CXp_MULTICALL   0x00000400      /* part of a multicall (so don't
 430                                            tear down context on exit). */
 431
 432 /* private flags for CXt_EVAL */
 433 #define CXp_REAL        0x00000100      /* truly eval'', not a lookalike */
 434 #define CXp_TRYBLOCK    0x00000200      /* eval{}, not eval'' or similar */
 435
 436 #ifdef USE_ITHREADS
 437 /* private flags for CXt_LOOP */
 438 #  define CXp_PADVAR    0x00000100      /* itervar lives on pad, iterdata
 439                                            has pad offset; if not set,
 440                                            iterdata holds GV* */
 441 #  define CxPADLOOP(c)  (((c)->cx_type & (CXt_LOOP|CXp_PADVAR))         \
 442                          == (CXt_LOOP|CXp_PADVAR))
 443 #endif
 444
 445 #define CxTYPE(c)       ((c)->cx_type & CXTYPEMASK)
 446 #define CxMULTICALL(c)  (((c)->cx_type & CXp_MULTICALL)                 \
 447                          == CXp_MULTICALL)
 448 #define CxREALEVAL(c)   (((c)->cx_type & (CXt_EVAL|CXp_REAL))           \
 449                          == (CXt_EVAL|CXp_REAL))
 450 #define CxTRYBLOCK(c)   (((c)->cx_type & (CXt_EVAL|CXp_TRYBLOCK))       \
 451                          == (CXt_EVAL|CXp_TRYBLOCK))
 452
 453 #define CXINC (cxstack_ix < cxstack_max ? ++cxstack_ix : (cxstack_ix = cxinc()))
 454
 455 /*
 456 =head1 "Gimme" Values
 457 */
 458
 459 /*
 460 =for apidoc AmU||G_SCALAR
 461 Used to indicate scalar context.  See C<GIMME_V>, C<GIMME>, and
 462 L<perlcall>.
 463
 464 =for apidoc AmU||G_ARRAY
 465 Used to indicate list context.  See C<GIMME_V>, C<GIMME> and
 466 L<perlcall>.
 467
 468 =for apidoc AmU||G_VOID
 469 Used to indicate void context.  See C<GIMME_V> and L<perlcall>.
 470
 471 =for apidoc AmU||G_DISCARD
 472 Indicates that arguments returned from a callback should be discarded.  See
 473 L<perlcall>.
 474
 475 =for apidoc AmU||G_EVAL
 476
 477 Used to force a Perl C<eval> wrapper around a callback.  See
 478 L<perlcall>.
 479
 480 =for apidoc AmU||G_NOARGS
 481
 482 Indicates that no arguments are being sent to a callback.  See
 483 L<perlcall>.
 484
 485 =cut
 486 */
 487
 488 #define G_SCALAR        0
 489 #define G_ARRAY         1
 490 #define G_VOID          128     /* skip this bit when adding flags below */
 491
 492 /* extra flags for Perl_call_* routines */
 493 #define G_DISCARD       2       /* Call FREETMPS. */
 494 #define G_EVAL          4       /* Assume eval {} around subroutine call. */
 495 #define G_NOARGS        8       /* Don't construct a @_ array. */
 496 #define G_KEEPERR      16       /* Append errors to $@, don't overwrite it */
 497 #define G_NODEBUG      32       /* Disable debugging at toplevel.  */
 498 #define G_METHOD       64       /* Calling method. */
 499
 500 /* flag bits for PL_in_eval */
 501 #define EVAL_NULL       0       /* not in an eval */
 502 #define EVAL_INEVAL     1       /* some enclosing scope is an eval */
 503 #define EVAL_WARNONLY   2       /* used by yywarn() when calling yyerror() */
 504 #define EVAL_KEEPERR    4       /* set by Perl_call_sv if G_KEEPERR */
 505 #define EVAL_INREQUIRE  8       /* The code is being required. */
 506
 507 /* Support for switching (stack and block) contexts.
 508  * This ensures magic doesn't invalidate local stack and cx pointers.
 509  */
 510
 511 #define PERLSI_UNKNOWN          -1
 512 #define PERLSI_UNDEF            0
 513 #define PERLSI_MAIN             1
 514 #define PERLSI_MAGIC            2
 515 #define PERLSI_SORT             3
 516 #define PERLSI_SIGNAL           4
 517 #define PERLSI_OVERLOAD         5
 518 #define PERLSI_DESTROY          6
 519 #define PERLSI_WARNHOOK         7
 520 #define PERLSI_DIEHOOK          8
 521 #define PERLSI_REQUIRE          9
 522
 523 struct stackinfo {
 524     AV *                si_stack;       /* stack for current runlevel */
 525     PERL_CONTEXT *      si_cxstack;     /* context stack for runlevel */
 526     I32                 si_cxix;        /* current context index */
 527     I32                 si_cxmax;       /* maximum allocated index */
 528     I32                 si_type;        /* type of runlevel */
 529     struct stackinfo *  si_prev;
 530     struct stackinfo *  si_next;
 531     I32                 si_markoff;     /* offset where markstack begins for us.
 532                                          * currently used only with DEBUGGING,
 533                                          * but not #ifdef-ed for bincompat */
 534 };
 535
 536 typedef struct stackinfo PERL_SI;
 537
 538 #define cxstack         (PL_curstackinfo->si_cxstack)
 539 #define cxstack_ix      (PL_curstackinfo->si_cxix)
 540 #define cxstack_max     (PL_curstackinfo->si_cxmax)
 541
 542 #ifdef DEBUGGING
 543 #  define       SET_MARK_OFFSET \
 544     PL_curstackinfo->si_markoff = PL_markstack_ptr - PL_markstack
 545 #else
 546 #  define       SET_MARK_OFFSET NOOP
 547 #endif
 548
 549 #define PUSHSTACKi(type) \
 550     STMT_START {                                                        \
 551         PERL_SI *next = PL_curstackinfo->si_next;                       \
 552         if (!next) {                                                    \
 553             next = new_stackinfo(32, 2048/sizeof(PERL_CONTEXT) - 1);    \
 554             next->si_prev = PL_curstackinfo;                            \
 555             PL_curstackinfo->si_next = next;                            \
 556         }                                                               \
 557         next->si_type = type;                                           \
 558         next->si_cxix = -1;                                             \
 559         AvFILLp(next->si_stack) = 0;                                    \
 560         SWITCHSTACK(PL_curstack,next->si_stack);                        \
 561         PL_curstackinfo = next;                                         \
 562         SET_MARK_OFFSET;                                                \
 563     } STMT_END
 564
 565 #define PUSHSTACK PUSHSTACKi(PERLSI_UNKNOWN)
 566
 567 /* POPSTACK works with PL_stack_sp, so it may need to be bracketed by
 568  * PUTBACK/SPAGAIN to flush/refresh any local SP that may be active */
 569 #define POPSTACK \
 570     STMT_START {                                                        \
 571         dSP;                                                            \
 572         PERL_SI * const prev = PL_curstackinfo->si_prev;                \
 573         if (!prev) {                                                    \
 574             PerlIO_printf(Perl_error_log, "panic: POPSTACK\n");         \
 575             my_exit(1);                                                 \
 576         }                                                               \
 577         SWITCHSTACK(PL_curstack,prev->si_stack);                        \
 578         /* don't free prev here, free them all at the END{} */          \
 579         PL_curstackinfo = prev;                                         \
 580     } STMT_END
 581
 582 #define POPSTACK_TO(s) \
 583     STMT_START {                                                        \
 584         while (PL_curstack != s) {                                      \
 585             dounwind(-1);                                               \
 586             POPSTACK;                                                   \
 587         }                                                               \
 588     } STMT_END
 589
 590 #define IN_PERL_COMPILETIME     (PL_curcop == &PL_compiling)
 591 #define IN_PERL_RUNTIME         (PL_curcop != &PL_compiling)
 592
 593 /*
 594 =head1 Multicall Functions
 595
 596 =for apidoc Ams||dMULTICALL
 597 Declare local variables for a multicall. See L<perlcall/Lightweight Callbacks>.
 598
 599 =for apidoc Ams||PUSH_MULTICALL
 600 Opening bracket for a lightweight callback.
 601 See L<perlcall/Lightweight Callbacks>.
 602
 603 =for apidoc Ams||MULTICALL
 604 Make a lightweight callback. See L<perlcall/Lightweight Callbacks>.
 605
 606 =for apidoc Ams||POP_MULTICALL
 607 Closing bracket for a lightweight callback.
 608 See L<perlcall/Lightweight Callbacks>.
 609
 610 =cut
 611 */
 612
 613 #define dMULTICALL \
 614     SV **newsp;                 /* set by POPBLOCK */                   \
 615     PERL_CONTEXT *cx;                                                   \
 616     CV *multicall_cv;                                                   \
 617     OP *multicall_cop;                                                  \
 618     bool multicall_oldcatch;                                            \
 619     U8 hasargs = 0              /* used by PUSHSUB */
 620
 621 #define PUSH_MULTICALL(the_cv) \
 622     STMT_START {                                                        \
 623         CV * const _nOnclAshIngNamE_ = the_cv;                          \
 624         CV * const cv = _nOnclAshIngNamE_;                              \
 625         AV * const padlist = CvPADLIST(cv);                             \
 626         ENTER;                                                          \
 627         multicall_oldcatch = CATCH_GET;                                 \
 628         SAVETMPS; SAVEVPTR(PL_op);                                      \
 629         CATCH_SET(TRUE);                                                \
 630         PUSHBLOCK(cx, CXt_SUB|CXp_MULTICALL, PL_stack_sp);              \
 631         PUSHSUB(cx);                                                    \
 632         if (++CvDEPTH(cv) >= 2) {                                       \
 633             PERL_STACK_OVERFLOW_CHECK();                                \
 634             Perl_pad_push(aTHX_ padlist, CvDEPTH(cv), 1);               \
 635         }                                                               \
 636         SAVECOMPPAD();                                                  \
 637         PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));                       \
 638         multicall_cv = cv;                                              \
 639         multicall_cop = CvSTART(cv);                                    \
 640     } STMT_END
 641
 642 #define MULTICALL \
 643     STMT_START {                                                        \
 644         PL_op = multicall_cop;                                          \
 645         CALLRUNOPS(aTHX);                                               \
 646     } STMT_END
 647
 648 #define POP_MULTICALL \
 649     STMT_START {                                                        \
 650         LEAVESUB(multicall_cv);                                         \
 651         CvDEPTH(multicall_cv)--;                                        \
 652         POPBLOCK(cx,PL_curpm);                                          \
 653         CATCH_SET(multicall_oldcatch);                                  \
 654         LEAVE;                                                          \
 655     } STMT_END