cop.h

   1 /*    cop.h
   2  *
   3  *    Copyright (c) 1991-1999, 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     HV *        cop_stash;      /* package line was compiled in */
  14     GV *        cop_filegv;     /* file the following line # is from */
  15     U32         cop_seq;        /* parse sequence number */
  16     I32         cop_arybase;    /* array base this line was compiled with */
  17     line_t      cop_line;       /* line # of this command */
  18     SV *        cop_warnings;   /* lexical warnings bitmask */
  19 };
  20
  21 #define Nullcop Null(COP*)
  22
  23 /*
  24  * Here we have some enormously heavy (or at least ponderous) wizardry.
  25  */
  26
  27 /* subroutine context */
  28 struct block_sub {
  29     CV *        cv;
  30     GV *        gv;
  31     GV *        dfoutgv;
  32 #ifndef USE_THREADS
  33     AV *        savearray;
  34 #endif /* USE_THREADS */
  35     AV *        argarray;
  36     U16         olddepth;
  37     U8          hasargs;
  38     U8          lval;           /* XXX merge lval and hasargs? */
  39 };
  40
  41 #define PUSHSUB(cx)                                                     \
  42         cx->blk_sub.cv = cv;                                            \
  43         cx->blk_sub.olddepth = CvDEPTH(cv);                             \
  44         cx->blk_sub.hasargs = hasargs;                                  \
  45         cx->blk_sub.lval = PL_op->op_private &                          \
  46                               (OPpLVAL_INTRO|OPpENTERSUB_INARGS);
  47
  48 #define PUSHFORMAT(cx)                                                  \
  49         cx->blk_sub.cv = cv;                                            \
  50         cx->blk_sub.gv = gv;                                            \
  51         cx->blk_sub.hasargs = 0;                                        \
  52         cx->blk_sub.dfoutgv = PL_defoutgv;                              \
  53         (void)SvREFCNT_inc(cx->blk_sub.dfoutgv)
  54
  55 #ifdef USE_THREADS
  56 #define POPSAVEARRAY() NOOP
  57 #else
  58 #define POPSAVEARRAY()                                                  \
  59     STMT_START {                                                        \
  60         SvREFCNT_dec(GvAV(PL_defgv));                                   \
  61         GvAV(PL_defgv) = cx->blk_sub.savearray;                         \
  62     } STMT_END
  63 #endif /* USE_THREADS */
  64
  65 #define POPSUB(cx,sv)                                                   \
  66     STMT_START {                                                        \
  67         if (cx->blk_sub.hasargs) {                                      \
  68             POPSAVEARRAY();                                             \
  69             /* abandon @_ if it got reified */                          \
  70             if (AvREAL(cx->blk_sub.argarray)) {                         \
  71                 SSize_t fill = AvFILLp(cx->blk_sub.argarray);           \
  72                 SvREFCNT_dec(cx->blk_sub.argarray);                     \
  73                 cx->blk_sub.argarray = newAV();                         \
  74                 av_extend(cx->blk_sub.argarray, fill);                  \
  75                 AvFLAGS(cx->blk_sub.argarray) = AVf_REIFY;              \
  76                 PL_curpad[0] = (SV*)cx->blk_sub.argarray;               \
  77             }                                                           \
  78         }                                                               \
  79         sv = (SV*)cx->blk_sub.cv;                                       \
  80         if (sv && (CvDEPTH((CV*)sv) = cx->blk_sub.olddepth))            \
  81             sv = Nullsv;                                                \
  82     } STMT_END
  83
  84 #define LEAVESUB(sv)                                                    \
  85     STMT_START {                                                        \
  86         if (sv)                                                         \
  87             SvREFCNT_dec(sv);                                           \
  88     } STMT_END
  89
  90 #define POPFORMAT(cx)                                                   \
  91         setdefout(cx->blk_sub.dfoutgv);                                 \
  92         SvREFCNT_dec(cx->blk_sub.dfoutgv);
  93
  94 /* eval context */
  95 struct block_eval {
  96     I32         old_in_eval;
  97     I32         old_op_type;
  98     char *      old_name;
  99     OP *        old_eval_root;
 100     SV *        cur_text;
 101 };
 102
 103 #define PUSHEVAL(cx,n,fgv)                                              \
 104         cx->blk_eval.old_in_eval = PL_in_eval;                          \
 105         cx->blk_eval.old_op_type = PL_op->op_type;                      \
 106         cx->blk_eval.old_name = n;                                      \
 107         cx->blk_eval.old_eval_root = PL_eval_root;                      \
 108         cx->blk_eval.cur_text = PL_linestr;
 109
 110 #define POPEVAL(cx)                                                     \
 111         PL_in_eval = cx->blk_eval.old_in_eval;                          \
 112         optype = cx->blk_eval.old_op_type;                              \
 113         PL_eval_root = cx->blk_eval.old_eval_root;
 114
 115 /* loop context */
 116 struct block_loop {
 117     char *      label;
 118     I32         resetsp;
 119     OP *        redo_op;
 120     OP *        next_op;
 121     OP *        last_op;
 122     SV **       itervar;
 123     SV *        itersave;
 124     SV *        iterlval;
 125     AV *        iterary;
 126     IV          iterix;
 127     IV          itermax;
 128 };
 129
 130 #define PUSHLOOP(cx, ivar, s)                                           \
 131         cx->blk_loop.label = PL_curcop->cop_label;                      \
 132         cx->blk_loop.resetsp = s - PL_stack_base;                       \
 133         cx->blk_loop.redo_op = cLOOP->op_redoop;                        \
 134         cx->blk_loop.next_op = cLOOP->op_nextop;                        \
 135         cx->blk_loop.last_op = cLOOP->op_lastop;                        \
 136         if (cx->blk_loop.itervar = (ivar))                              \
 137             cx->blk_loop.itersave = SvREFCNT_inc(*cx->blk_loop.itervar);\
 138         cx->blk_loop.iterlval = Nullsv;                                 \
 139         cx->blk_loop.iterary = Nullav;                                  \
 140         cx->blk_loop.iterix = -1;
 141
 142 #define POPLOOP(cx)                                                     \
 143         SvREFCNT_dec(cx->blk_loop.iterlval);                            \
 144         if (cx->blk_loop.itervar) {                                     \
 145             sv_2mortal(*(cx->blk_loop.itervar));                        \
 146             *(cx->blk_loop.itervar) = cx->blk_loop.itersave;            \
 147         }                                                               \
 148         if (cx->blk_loop.iterary && cx->blk_loop.iterary != PL_curstack)\
 149             SvREFCNT_dec(cx->blk_loop.iterary);
 150
 151 /* context common to subroutines, evals and loops */
 152 struct block {
 153     I32         blku_oldsp;     /* stack pointer to copy stuff down to */
 154     COP *       blku_oldcop;    /* old curcop pointer */
 155     I32         blku_oldretsp;  /* return stack index */
 156     I32         blku_oldmarksp; /* mark stack index */
 157     I32         blku_oldscopesp;        /* scope stack index */
 158     PMOP *      blku_oldpm;     /* values of pattern match vars */
 159     U8          blku_gimme;     /* is this block running in list context? */
 160
 161     union {
 162         struct block_sub        blku_sub;
 163         struct block_eval       blku_eval;
 164         struct block_loop       blku_loop;
 165     } blk_u;
 166 };
 167 #define blk_oldsp       cx_u.cx_blk.blku_oldsp
 168 #define blk_oldcop      cx_u.cx_blk.blku_oldcop
 169 #define blk_oldretsp    cx_u.cx_blk.blku_oldretsp
 170 #define blk_oldmarksp   cx_u.cx_blk.blku_oldmarksp
 171 #define blk_oldscopesp  cx_u.cx_blk.blku_oldscopesp
 172 #define blk_oldpm       cx_u.cx_blk.blku_oldpm
 173 #define blk_gimme       cx_u.cx_blk.blku_gimme
 174 #define blk_sub         cx_u.cx_blk.blk_u.blku_sub
 175 #define blk_eval        cx_u.cx_blk.blk_u.blku_eval
 176 #define blk_loop        cx_u.cx_blk.blk_u.blku_loop
 177
 178 /* Enter a block. */
 179 #define PUSHBLOCK(cx,t,sp) CXINC, cx = &cxstack[cxstack_ix],            \
 180         cx->cx_type             = t,                                    \
 181         cx->blk_oldsp           = sp - PL_stack_base,                   \
 182         cx->blk_oldcop          = PL_curcop,                            \
 183         cx->blk_oldmarksp       = PL_markstack_ptr - PL_markstack,      \
 184         cx->blk_oldscopesp      = PL_scopestack_ix,                     \
 185         cx->blk_oldretsp        = PL_retstack_ix,                       \
 186         cx->blk_oldpm           = PL_curpm,                             \
 187         cx->blk_gimme           = gimme;                                \
 188         DEBUG_l( PerlIO_printf(Perl_debug_log, "Entering block %ld, type %s\n", \
 189                     (long)cxstack_ix, PL_block_type[CxTYPE(cx)]); )
 190
 191 /* Exit a block (RETURN and LAST). */
 192 #define POPBLOCK(cx,pm) cx = &cxstack[cxstack_ix--],                    \
 193         newsp            = PL_stack_base + cx->blk_oldsp,               \
 194         PL_curcop        = cx->blk_oldcop,                              \
 195         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
 196         PL_scopestack_ix = cx->blk_oldscopesp,                          \
 197         PL_retstack_ix   = cx->blk_oldretsp,                            \
 198         pm               = cx->blk_oldpm,                               \
 199         gimme            = cx->blk_gimme;                               \
 200         DEBUG_l( PerlIO_printf(Perl_debug_log, "Leaving block %ld, type %s\n",          \
 201                     (long)cxstack_ix+1,PL_block_type[CxTYPE(cx)]); )
 202
 203 /* Continue a block elsewhere (NEXT and REDO). */
 204 #define TOPBLOCK(cx) cx  = &cxstack[cxstack_ix],                        \
 205         PL_stack_sp      = PL_stack_base + cx->blk_oldsp,               \
 206         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
 207         PL_scopestack_ix = cx->blk_oldscopesp,                          \
 208         PL_retstack_ix   = cx->blk_oldretsp,                            \
 209         PL_curpm         = cx->blk_oldpm
 210
 211 /* substitution context */
 212 struct subst {
 213     I32         sbu_iters;
 214     I32         sbu_maxiters;
 215     I32         sbu_rflags;
 216     I32         sbu_oldsave;
 217     bool        sbu_once;
 218     bool        sbu_rxtainted;
 219     char *      sbu_orig;
 220     SV *        sbu_dstr;
 221     SV *        sbu_targ;
 222     char *      sbu_s;
 223     char *      sbu_m;
 224     char *      sbu_strend;
 225     void *      sbu_rxres;
 226     REGEXP *    sbu_rx;
 227 };
 228 #define sb_iters        cx_u.cx_subst.sbu_iters
 229 #define sb_maxiters     cx_u.cx_subst.sbu_maxiters
 230 #define sb_rflags       cx_u.cx_subst.sbu_rflags
 231 #define sb_oldsave      cx_u.cx_subst.sbu_oldsave
 232 #define sb_once         cx_u.cx_subst.sbu_once
 233 #define sb_rxtainted    cx_u.cx_subst.sbu_rxtainted
 234 #define sb_orig         cx_u.cx_subst.sbu_orig
 235 #define sb_dstr         cx_u.cx_subst.sbu_dstr
 236 #define sb_targ         cx_u.cx_subst.sbu_targ
 237 #define sb_s            cx_u.cx_subst.sbu_s
 238 #define sb_m            cx_u.cx_subst.sbu_m
 239 #define sb_strend       cx_u.cx_subst.sbu_strend
 240 #define sb_rxres        cx_u.cx_subst.sbu_rxres
 241 #define sb_rx           cx_u.cx_subst.sbu_rx
 242
 243 #define PUSHSUBST(cx) CXINC, cx = &cxstack[cxstack_ix],                 \
 244         cx->sb_iters            = iters,                                \
 245         cx->sb_maxiters         = maxiters,                             \
 246         cx->sb_rflags           = r_flags,                              \
 247         cx->sb_oldsave          = oldsave,                              \
 248         cx->sb_once             = once,                                 \
 249         cx->sb_rxtainted        = rxtainted,                            \
 250         cx->sb_orig             = orig,                                 \
 251         cx->sb_dstr             = dstr,                                 \
 252         cx->sb_targ             = targ,                                 \
 253         cx->sb_s                = s,                                    \
 254         cx->sb_m                = m,                                    \
 255         cx->sb_strend           = strend,                               \
 256         cx->sb_rxres            = Null(void*),                          \
 257         cx->sb_rx               = rx,                                   \
 258         cx->cx_type             = CXt_SUBST;                            \
 259         rxres_save(&cx->sb_rxres, rx)
 260
 261 #define POPSUBST(cx) cx = &cxstack[cxstack_ix--];                       \
 262         rxres_free(&cx->sb_rxres)
 263
 264 struct context {
 265     U32         cx_type;        /* what kind of context this is */
 266     union {
 267         struct block    cx_blk;
 268         struct subst    cx_subst;
 269     } cx_u;
 270 };
 271
 272 #define CXTYPEMASK      0xff
 273 #define CXt_NULL        0
 274 #define CXt_SUB         1
 275 #define CXt_EVAL        2
 276 #define CXt_LOOP        3
 277 #define CXt_SUBST       4
 278 #define CXt_BLOCK       5
 279
 280 /* private flags for CXt_EVAL */
 281 #define CXp_REAL        0x00000100      /* truly eval'', not a lookalike */
 282
 283 #define CxTYPE(c)       ((c)->cx_type & CXTYPEMASK)
 284 #define CxREALEVAL(c)   (((c)->cx_type & (CXt_EVAL|CXp_REAL)) == (CXt_EVAL|CXp_REAL))
 285
 286 #define CXINC (cxstack_ix < cxstack_max ? ++cxstack_ix : (cxstack_ix = cxinc()))
 287
 288 /* "gimme" values */
 289 #define G_SCALAR        0
 290 #define G_ARRAY         1
 291 #define G_VOID          128     /* skip this bit when adding flags below */
 292
 293 /* extra flags for Perl_call_* routines */
 294 #define G_DISCARD       2       /* Call FREETMPS. */
 295 #define G_EVAL          4       /* Assume eval {} around subroutine call. */
 296 #define G_NOARGS        8       /* Don't construct a @_ array. */
 297 #define G_KEEPERR      16       /* Append errors to $@, don't overwrite it */
 298 #define G_NODEBUG      32       /* Disable debugging at toplevel.  */
 299 #define G_NOCATCH      64       /* Don't do CATCH_SET() */
 300
 301 /* flag bits for PL_in_eval */
 302 #define EVAL_NULL       0       /* not in an eval */
 303 #define EVAL_INEVAL     1       /* some enclosing scope is an eval */
 304 #define EVAL_WARNONLY   2       /* used by yywarn() when calling yyerror() */
 305 #define EVAL_KEEPERR    4       /* set by Perl_call_sv if G_KEEPERR */
 306
 307 /* Support for switching (stack and block) contexts.
 308  * This ensures magic doesn't invalidate local stack and cx pointers.
 309  */
 310
 311 #define PERLSI_UNKNOWN          -1
 312 #define PERLSI_UNDEF            0
 313 #define PERLSI_MAIN             1
 314 #define PERLSI_MAGIC            2
 315 #define PERLSI_SORT             3
 316 #define PERLSI_SIGNAL           4
 317 #define PERLSI_OVERLOAD         5
 318 #define PERLSI_DESTROY          6
 319 #define PERLSI_WARNHOOK         7
 320 #define PERLSI_DIEHOOK          8
 321 #define PERLSI_REQUIRE          9
 322
 323 struct stackinfo {
 324     AV *                si_stack;       /* stack for current runlevel */
 325     PERL_CONTEXT *      si_cxstack;     /* context stack for runlevel */
 326     I32                 si_cxix;        /* current context index */
 327     I32                 si_cxmax;       /* maximum allocated index */
 328     I32                 si_type;        /* type of runlevel */
 329     struct stackinfo *  si_prev;
 330     struct stackinfo *  si_next;
 331     I32 *               si_markbase;    /* where markstack begins for us.
 332                                          * currently used only with DEBUGGING,
 333                                          * but not #ifdef-ed for bincompat */
 334 };
 335
 336 typedef struct stackinfo PERL_SI;
 337
 338 #define cxstack         (PL_curstackinfo->si_cxstack)
 339 #define cxstack_ix      (PL_curstackinfo->si_cxix)
 340 #define cxstack_max     (PL_curstackinfo->si_cxmax)
 341
 342 #ifdef DEBUGGING
 343 #  define       SET_MARKBASE PL_curstackinfo->si_markbase = PL_markstack_ptr
 344 #else
 345 #  define       SET_MARKBASE NOOP
 346 #endif
 347
 348 #define PUSHSTACKi(type) \
 349     STMT_START {                                                        \
 350         PERL_SI *next = PL_curstackinfo->si_next;                       \
 351         if (!next) {                                                    \
 352             next = new_stackinfo(32, 2048/sizeof(PERL_CONTEXT) - 1);    \
 353             next->si_prev = PL_curstackinfo;                            \
 354             PL_curstackinfo->si_next = next;                            \
 355         }                                                               \
 356         next->si_type = type;                                           \
 357         next->si_cxix = -1;                                             \
 358         AvFILLp(next->si_stack) = 0;                                    \
 359         SWITCHSTACK(PL_curstack,next->si_stack);                        \
 360         PL_curstackinfo = next;                                         \
 361         SET_MARKBASE;                                                   \
 362     } STMT_END
 363
 364 #define PUSHSTACK PUSHSTACKi(PERLSI_UNKNOWN)
 365
 366 /* POPSTACK works with PL_stack_sp, so it may need to be bracketed by
 367  * PUTBACK/SPAGAIN to flush/refresh any local SP that may be active */
 368 #define POPSTACK \
 369     STMT_START {                                                        \
 370         djSP;                                                           \
 371         PERL_SI *prev = PL_curstackinfo->si_prev;                       \
 372         if (!prev) {                                                    \
 373             PerlIO_printf(Perl_error_log, "panic: POPSTACK\n");         \
 374             my_exit(1);                                                 \
 375         }                                                               \
 376         SWITCHSTACK(PL_curstack,prev->si_stack);                        \
 377         /* don't free prev here, free them all at the END{} */          \
 378         PL_curstackinfo = prev;                                         \
 379     } STMT_END
 380
 381 #define POPSTACK_TO(s) \
 382     STMT_START {                                                        \
 383         while (PL_curstack != s) {                                      \
 384             dounwind(-1);                                               \
 385             POPSTACK;                                                   \
 386         }                                                               \
 387     } STMT_END