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 #define POPSUB(cx)                                                      \
  56         { struct block_sub cxsub;                                       \
  57           POPSUB1(cx);                                                  \
  58           POPSUB2(); }
  59
  60 #define POPSUB1(cx)                                                     \
  61         cxsub = cx->blk_sub;    /* because DESTROY may clobber *cx */
  62
  63 #ifdef USE_THREADS
  64 #define POPSAVEARRAY() NOOP
  65 #else
  66 #define POPSAVEARRAY()                                                  \
  67     STMT_START {                                                        \
  68         SvREFCNT_dec(GvAV(PL_defgv));                                   \
  69         GvAV(PL_defgv) = cxsub.savearray;                                       \
  70     } STMT_END
  71 #endif /* USE_THREADS */
  72
  73 #define POPSUB2()                                                       \
  74         if (cxsub.hasargs) {                                            \
  75             POPSAVEARRAY();                                             \
  76             /* destroy arg array */                                     \
  77             av_clear(cxsub.argarray);                                   \
  78             AvREAL_off(cxsub.argarray);                                 \
  79             AvREIFY_on(cxsub.argarray);                                 \
  80         }                                                               \
  81         if (cxsub.cv) {                                                 \
  82             if (!(CvDEPTH(cxsub.cv) = cxsub.olddepth))                  \
  83                 SvREFCNT_dec(cxsub.cv);                                 \
  84         }
  85
  86 #define POPFORMAT(cx)                                                   \
  87         setdefout(cx->blk_sub.dfoutgv);                                 \
  88         SvREFCNT_dec(cx->blk_sub.dfoutgv);
  89
  90 /* eval context */
  91 struct block_eval {
  92     I32         old_in_eval;
  93     I32         old_op_type;
  94     char *      old_name;
  95     OP *        old_eval_root;
  96     SV *        cur_text;
  97 };
  98
  99 #define PUSHEVAL(cx,n,fgv)                                              \
 100         cx->blk_eval.old_in_eval = PL_in_eval;                          \
 101         cx->blk_eval.old_op_type = PL_op->op_type;                              \
 102         cx->blk_eval.old_name = n;                                      \
 103         cx->blk_eval.old_eval_root = PL_eval_root;                              \
 104         cx->blk_eval.cur_text = PL_linestr;
 105
 106 #define POPEVAL(cx)                                                     \
 107         PL_in_eval = cx->blk_eval.old_in_eval;                          \
 108         optype = cx->blk_eval.old_op_type;                              \
 109         PL_eval_root = cx->blk_eval.old_eval_root;
 110
 111 /* loop context */
 112 struct block_loop {
 113     char *      label;
 114     I32         resetsp;
 115     OP *        redo_op;
 116     OP *        next_op;
 117     OP *        last_op;
 118     SV **       itervar;
 119     SV *        itersave;
 120     SV *        iterlval;
 121     AV *        iterary;
 122     IV          iterix;
 123     IV          itermax;
 124 };
 125
 126 #define PUSHLOOP(cx, ivar, s)                                           \
 127         cx->blk_loop.label = PL_curcop->cop_label;                              \
 128         cx->blk_loop.resetsp = s - PL_stack_base;                               \
 129         cx->blk_loop.redo_op = cLOOP->op_redoop;                        \
 130         cx->blk_loop.next_op = cLOOP->op_nextop;                        \
 131         cx->blk_loop.last_op = cLOOP->op_lastop;                        \
 132         if (cx->blk_loop.itervar = (ivar))                              \
 133             cx->blk_loop.itersave = SvREFCNT_inc(*cx->blk_loop.itervar);\
 134         cx->blk_loop.iterlval = Nullsv;                                 \
 135         cx->blk_loop.iterary = Nullav;                                  \
 136         cx->blk_loop.iterix = -1;
 137
 138 #define POPLOOP(cx)                                                     \
 139         { struct block_loop cxloop;                                     \
 140           POPLOOP1(cx);                                                 \
 141           POPLOOP2(); }
 142
 143 #define POPLOOP1(cx)                                                    \
 144         cxloop = cx->blk_loop;  /* because DESTROY may clobber *cx */   \
 145         newsp = PL_stack_base + cxloop.resetsp;
 146
 147 #define POPLOOP2()                                                      \
 148         SvREFCNT_dec(cxloop.iterlval);                                  \
 149         if (cxloop.itervar) {                                           \
 150             sv_2mortal(*cxloop.itervar);                                \
 151             *cxloop.itervar = cxloop.itersave;                          \
 152         }                                                               \
 153         if (cxloop.iterary && cxloop.iterary != PL_curstack)            \
 154             SvREFCNT_dec(cxloop.iterary);
 155
 156 /* context common to subroutines, evals and loops */
 157 struct block {
 158     I32         blku_oldsp;     /* stack pointer to copy stuff down to */
 159     COP *       blku_oldcop;    /* old curcop pointer */
 160     I32         blku_oldretsp;  /* return stack index */
 161     I32         blku_oldmarksp; /* mark stack index */
 162     I32         blku_oldscopesp;        /* scope stack index */
 163     PMOP *      blku_oldpm;     /* values of pattern match vars */
 164     U8          blku_gimme;     /* is this block running in list context? */
 165
 166     union {
 167         struct block_sub        blku_sub;
 168         struct block_eval       blku_eval;
 169         struct block_loop       blku_loop;
 170     } blk_u;
 171 };
 172 #define blk_oldsp       cx_u.cx_blk.blku_oldsp
 173 #define blk_oldcop      cx_u.cx_blk.blku_oldcop
 174 #define blk_oldretsp    cx_u.cx_blk.blku_oldretsp
 175 #define blk_oldmarksp   cx_u.cx_blk.blku_oldmarksp
 176 #define blk_oldscopesp  cx_u.cx_blk.blku_oldscopesp
 177 #define blk_oldpm       cx_u.cx_blk.blku_oldpm
 178 #define blk_gimme       cx_u.cx_blk.blku_gimme
 179 #define blk_sub         cx_u.cx_blk.blk_u.blku_sub
 180 #define blk_eval        cx_u.cx_blk.blk_u.blku_eval
 181 #define blk_loop        cx_u.cx_blk.blk_u.blku_loop
 182
 183 /* Enter a block. */
 184 #define PUSHBLOCK(cx,t,sp) CXINC, cx = &cxstack[cxstack_ix],            \
 185         cx->cx_type             = t,                                    \
 186         cx->blk_oldsp           = sp - PL_stack_base,                   \
 187         cx->blk_oldcop          = PL_curcop,                            \
 188         cx->blk_oldmarksp       = PL_markstack_ptr - PL_markstack,      \
 189         cx->blk_oldscopesp      = PL_scopestack_ix,                     \
 190         cx->blk_oldretsp        = PL_retstack_ix,                       \
 191         cx->blk_oldpm           = PL_curpm,                             \
 192         cx->blk_gimme           = gimme;                                \
 193         DEBUG_l( PerlIO_printf(PerlIO_stderr(), "Entering block %ld, type %s\n",        \
 194                     (long)cxstack_ix, PL_block_type[CxTYPE(cx)]); )
 195
 196 /* Exit a block (RETURN and LAST). */
 197 #define POPBLOCK(cx,pm) cx = &cxstack[cxstack_ix--],                    \
 198         newsp            = PL_stack_base + cx->blk_oldsp,               \
 199         PL_curcop        = cx->blk_oldcop,                              \
 200         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
 201         PL_scopestack_ix = cx->blk_oldscopesp,                          \
 202         PL_retstack_ix   = cx->blk_oldretsp,                            \
 203         pm               = cx->blk_oldpm,                               \
 204         gimme            = cx->blk_gimme;                               \
 205         DEBUG_l( PerlIO_printf(PerlIO_stderr(), "Leaving block %ld, type %s\n",         \
 206                     (long)cxstack_ix+1,PL_block_type[CxTYPE(cx)]); )
 207
 208 /* Continue a block elsewhere (NEXT and REDO). */
 209 #define TOPBLOCK(cx) cx  = &cxstack[cxstack_ix],                        \
 210         PL_stack_sp      = PL_stack_base + cx->blk_oldsp,               \
 211         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
 212         PL_scopestack_ix = cx->blk_oldscopesp,                          \
 213         PL_retstack_ix   = cx->blk_oldretsp,                            \
 214         PL_curpm         = cx->blk_oldpm
 215
 216 /* substitution context */
 217 struct subst {
 218     I32         sbu_iters;
 219     I32         sbu_maxiters;
 220     I32         sbu_rflags;
 221     I32         sbu_oldsave;
 222     bool        sbu_once;
 223     bool        sbu_rxtainted;
 224     char *      sbu_orig;
 225     SV *        sbu_dstr;
 226     SV *        sbu_targ;
 227     char *      sbu_s;
 228     char *      sbu_m;
 229     char *      sbu_strend;
 230     void *      sbu_rxres;
 231     REGEXP *    sbu_rx;
 232 };
 233 #define sb_iters        cx_u.cx_subst.sbu_iters
 234 #define sb_maxiters     cx_u.cx_subst.sbu_maxiters
 235 #define sb_rflags       cx_u.cx_subst.sbu_rflags
 236 #define sb_oldsave      cx_u.cx_subst.sbu_oldsave
 237 #define sb_once         cx_u.cx_subst.sbu_once
 238 #define sb_rxtainted    cx_u.cx_subst.sbu_rxtainted
 239 #define sb_orig         cx_u.cx_subst.sbu_orig
 240 #define sb_dstr         cx_u.cx_subst.sbu_dstr
 241 #define sb_targ         cx_u.cx_subst.sbu_targ
 242 #define sb_s            cx_u.cx_subst.sbu_s
 243 #define sb_m            cx_u.cx_subst.sbu_m
 244 #define sb_strend       cx_u.cx_subst.sbu_strend
 245 #define sb_rxres        cx_u.cx_subst.sbu_rxres
 246 #define sb_rx           cx_u.cx_subst.sbu_rx
 247
 248 #define PUSHSUBST(cx) CXINC, cx = &cxstack[cxstack_ix],                 \
 249         cx->sb_iters            = iters,                                \
 250         cx->sb_maxiters         = maxiters,                             \
 251         cx->sb_rflags           = r_flags,                              \
 252         cx->sb_oldsave          = oldsave,                              \
 253         cx->sb_once             = once,                                 \
 254         cx->sb_rxtainted        = rxtainted,                            \
 255         cx->sb_orig             = orig,                                 \
 256         cx->sb_dstr             = dstr,                                 \
 257         cx->sb_targ             = targ,                                 \
 258         cx->sb_s                = s,                                    \
 259         cx->sb_m                = m,                                    \
 260         cx->sb_strend           = strend,                               \
 261         cx->sb_rxres            = Null(void*),                          \
 262         cx->sb_rx               = rx,                                   \
 263         cx->cx_type             = CXt_SUBST;                            \
 264         rxres_save(&cx->sb_rxres, rx)
 265
 266 #define POPSUBST(cx) cx = &cxstack[cxstack_ix--];                       \
 267         rxres_free(&cx->sb_rxres)
 268
 269 struct context {
 270     U32         cx_type;        /* what kind of context this is */
 271     union {
 272         struct block    cx_blk;
 273         struct subst    cx_subst;
 274     } cx_u;
 275 };
 276
 277 #define CXTYPEMASK      0xff
 278 #define CXt_NULL        0
 279 #define CXt_SUB         1
 280 #define CXt_EVAL        2
 281 #define CXt_LOOP        3
 282 #define CXt_SUBST       4
 283 #define CXt_BLOCK       5
 284
 285 /* private flags for CXt_EVAL */
 286 #define CXp_REAL        0x00000100      /* truly eval'', not a lookalike */
 287
 288 #define CxTYPE(c)       ((c)->cx_type & CXTYPEMASK)
 289 #define CxREALEVAL(c)   (((c)->cx_type & (CXt_EVAL|CXp_REAL)) == (CXt_EVAL|CXp_REAL))
 290
 291 #define CXINC (cxstack_ix < cxstack_max ? ++cxstack_ix : (cxstack_ix = cxinc()))
 292
 293 /* "gimme" values */
 294 #define G_SCALAR        0
 295 #define G_ARRAY         1
 296 #define G_VOID          128     /* skip this bit when adding flags below */
 297
 298 /* extra flags for Perl_call_* routines */
 299 #define G_DISCARD       2       /* Call FREETMPS. */
 300 #define G_EVAL          4       /* Assume eval {} around subroutine call. */
 301 #define G_NOARGS        8       /* Don't construct a @_ array. */
 302 #define G_KEEPERR      16       /* Append errors to $@, don't overwrite it */
 303 #define G_NODEBUG      32       /* Disable debugging at toplevel.  */
 304 #define G_NOCATCH      64       /* Don't do CATCH_SET() */
 305
 306 /* flag bits for PL_in_eval */
 307 #define EVAL_NULL       0       /* not in an eval */
 308 #define EVAL_INEVAL     1       /* some enclosing scope is an eval */
 309 #define EVAL_WARNONLY   2       /* used by yywarn() when calling yyerror() */
 310 #define EVAL_KEEPERR    4       /* set by Perl_call_sv if G_KEEPERR */
 311
 312 /* Support for switching (stack and block) contexts.
 313  * This ensures magic doesn't invalidate local stack and cx pointers.
 314  */
 315
 316 #define PERLSI_UNKNOWN          -1
 317 #define PERLSI_UNDEF            0
 318 #define PERLSI_MAIN             1
 319 #define PERLSI_MAGIC            2
 320 #define PERLSI_SORT             3
 321 #define PERLSI_SIGNAL           4
 322 #define PERLSI_OVERLOAD         5
 323 #define PERLSI_DESTROY          6
 324 #define PERLSI_WARNHOOK         7
 325 #define PERLSI_DIEHOOK          8
 326 #define PERLSI_REQUIRE          9
 327
 328 struct stackinfo {
 329     AV *                si_stack;       /* stack for current runlevel */
 330     PERL_CONTEXT *      si_cxstack;     /* context stack for runlevel */
 331     I32                 si_cxix;        /* current context index */
 332     I32                 si_cxmax;       /* maximum allocated index */
 333     I32                 si_type;        /* type of runlevel */
 334     struct stackinfo *  si_prev;
 335     struct stackinfo *  si_next;
 336     I32 *               si_markbase;    /* where markstack begins for us.
 337                                          * currently used only with DEBUGGING,
 338                                          * but not #ifdef-ed for bincompat */
 339 };
 340
 341 typedef struct stackinfo PERL_SI;
 342
 343 #define cxstack         (PL_curstackinfo->si_cxstack)
 344 #define cxstack_ix      (PL_curstackinfo->si_cxix)
 345 #define cxstack_max     (PL_curstackinfo->si_cxmax)
 346
 347 #ifdef DEBUGGING
 348 #  define       SET_MARKBASE PL_curstackinfo->si_markbase = PL_markstack_ptr
 349 #else
 350 #  define       SET_MARKBASE NOOP
 351 #endif
 352
 353 #define PUSHSTACKi(type) \
 354     STMT_START {                                                        \
 355         PERL_SI *next = PL_curstackinfo->si_next;                       \
 356         if (!next) {                                                    \
 357             next = new_stackinfo(32, 2048/sizeof(PERL_CONTEXT) - 1);    \
 358             next->si_prev = PL_curstackinfo;                            \
 359             PL_curstackinfo->si_next = next;                            \
 360         }                                                               \
 361         next->si_type = type;                                           \
 362         next->si_cxix = -1;                                             \
 363         AvFILLp(next->si_stack) = 0;                                    \
 364         SWITCHSTACK(PL_curstack,next->si_stack);                        \
 365         PL_curstackinfo = next;                                         \
 366         SET_MARKBASE;                                                   \
 367     } STMT_END
 368
 369 #define PUSHSTACK PUSHSTACKi(PERLSI_UNKNOWN)
 370
 371 /* POPSTACK works with PL_stack_sp, so it may need to be bracketed by
 372  * PUTBACK/SPAGAIN to flush/refresh any local SP that may be active */
 373 #define POPSTACK \
 374     STMT_START {                                                        \
 375         djSP;                                                           \
 376         PERL_SI *prev = PL_curstackinfo->si_prev;                       \
 377         if (!prev) {                                                    \
 378             PerlIO_printf(PerlIO_stderr(), "panic: POPSTACK\n");        \
 379             my_exit(1);                                                 \
 380         }                                                               \
 381         SWITCHSTACK(PL_curstack,prev->si_stack);                        \
 382         /* don't free prev here, free them all at the END{} */          \
 383         PL_curstackinfo = prev;                                         \
 384     } STMT_END
 385
 386 #define POPSTACK_TO(s) \
 387     STMT_START {                                                        \
 388         while (PL_curstack != s) {                                      \
 389             dounwind(-1);                                               \
 390             POPSTACK;                                                   \
 391         }                                                               \
 392     } STMT_END