cop.h

   1 /*    cop.h
   2  *
   3  *    Copyright (c) 1991-1997, 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 };
  39
  40 #define PUSHSUB(cx)                                                     \
  41         cx->blk_sub.cv = cv;                                            \
  42         cx->blk_sub.olddepth = CvDEPTH(cv);                             \
  43         cx->blk_sub.hasargs = hasargs;
  44
  45 #define PUSHFORMAT(cx)                                                  \
  46         cx->blk_sub.cv = cv;                                            \
  47         cx->blk_sub.gv = gv;                                            \
  48         cx->blk_sub.hasargs = 0;                                        \
  49         cx->blk_sub.dfoutgv = PL_defoutgv;                              \
  50         (void)SvREFCNT_inc(cx->blk_sub.dfoutgv)
  51
  52 #define POPSUB(cx)                                                      \
  53         { struct block_sub cxsub;                                       \
  54           POPSUB1(cx);                                                  \
  55           POPSUB2(); }
  56
  57 #define POPSUB1(cx)                                                     \
  58         cxsub = cx->blk_sub;    /* because DESTROY may clobber *cx */
  59
  60 #ifdef USE_THREADS
  61 #define POPSAVEARRAY() NOOP
  62 #else
  63 #define POPSAVEARRAY()                                                  \
  64     STMT_START {                                                        \
  65         SvREFCNT_dec(GvAV(PL_defgv));                                   \
  66         GvAV(PL_defgv) = cxsub.savearray;                                       \
  67     } STMT_END
  68 #endif /* USE_THREADS */
  69
  70 #define POPSUB2()                                                       \
  71         if (cxsub.hasargs) {                                            \
  72             POPSAVEARRAY();                                             \
  73             /* destroy arg array */                                     \
  74             av_clear(cxsub.argarray);                                   \
  75             AvREAL_off(cxsub.argarray);                                 \
  76         }                                                               \
  77         if (cxsub.cv) {                                                 \
  78             if (!(CvDEPTH(cxsub.cv) = cxsub.olddepth))                  \
  79                 SvREFCNT_dec(cxsub.cv);                                 \
  80         }
  81
  82 #define POPFORMAT(cx)                                                   \
  83         setdefout(cx->blk_sub.dfoutgv);                                 \
  84         SvREFCNT_dec(cx->blk_sub.dfoutgv);
  85
  86 /* eval context */
  87 struct block_eval {
  88     I32         old_in_eval;
  89     I32         old_op_type;
  90     char *      old_name;
  91     OP *        old_eval_root;
  92     SV *        cur_text;
  93 };
  94
  95 #define PUSHEVAL(cx,n,fgv)                                              \
  96         cx->blk_eval.old_in_eval = PL_in_eval;                          \
  97         cx->blk_eval.old_op_type = PL_op->op_type;                              \
  98         cx->blk_eval.old_name = n;                                      \
  99         cx->blk_eval.old_eval_root = PL_eval_root;                              \
 100         cx->blk_eval.cur_text = PL_linestr;
 101
 102 #define POPEVAL(cx)                                                     \
 103         PL_in_eval = cx->blk_eval.old_in_eval;                          \
 104         optype = cx->blk_eval.old_op_type;                              \
 105         PL_eval_root = cx->blk_eval.old_eval_root;
 106
 107 /* loop context */
 108 struct block_loop {
 109     char *      label;
 110     I32         resetsp;
 111     OP *        redo_op;
 112     OP *        next_op;
 113     OP *        last_op;
 114     SV **       itervar;
 115     SV *        itersave;
 116     SV *        iterlval;
 117     AV *        iterary;
 118     IV          iterix;
 119     IV          itermax;
 120 };
 121
 122 #define PUSHLOOP(cx, ivar, s)                                           \
 123         cx->blk_loop.label = PL_curcop->cop_label;                              \
 124         cx->blk_loop.resetsp = s - PL_stack_base;                               \
 125         cx->blk_loop.redo_op = cLOOP->op_redoop;                        \
 126         cx->blk_loop.next_op = cLOOP->op_nextop;                        \
 127         cx->blk_loop.last_op = cLOOP->op_lastop;                        \
 128         if (cx->blk_loop.itervar = (ivar))                              \
 129             cx->blk_loop.itersave = SvREFCNT_inc(*cx->blk_loop.itervar);\
 130         cx->blk_loop.iterlval = Nullsv;                                 \
 131         cx->blk_loop.iterary = Nullav;                                  \
 132         cx->blk_loop.iterix = -1;
 133
 134 #define POPLOOP(cx)                                                     \
 135         { struct block_loop cxloop;                                     \
 136           POPLOOP1(cx);                                                 \
 137           POPLOOP2(); }
 138
 139 #define POPLOOP1(cx)                                                    \
 140         cxloop = cx->blk_loop;  /* because DESTROY may clobber *cx */   \
 141         newsp = PL_stack_base + cxloop.resetsp;
 142
 143 #define POPLOOP2()                                                      \
 144         SvREFCNT_dec(cxloop.iterlval);                                  \
 145         if (cxloop.itervar) {                                           \
 146             sv_2mortal(*cxloop.itervar);                                \
 147             *cxloop.itervar = cxloop.itersave;                          \
 148         }                                                               \
 149         if (cxloop.iterary && cxloop.iterary != PL_curstack)            \
 150             SvREFCNT_dec(cxloop.iterary);
 151
 152 /* context common to subroutines, evals and loops */
 153 struct block {
 154     I32         blku_oldsp;     /* stack pointer to copy stuff down to */
 155     COP *       blku_oldcop;    /* old curcop pointer */
 156     I32         blku_oldretsp;  /* return stack index */
 157     I32         blku_oldmarksp; /* mark stack index */
 158     I32         blku_oldscopesp;        /* scope stack index */
 159     PMOP *      blku_oldpm;     /* values of pattern match vars */
 160     U8          blku_gimme;     /* is this block running in list context? */
 161
 162     union {
 163         struct block_sub        blku_sub;
 164         struct block_eval       blku_eval;
 165         struct block_loop       blku_loop;
 166     } blk_u;
 167 };
 168 #define blk_oldsp       cx_u.cx_blk.blku_oldsp
 169 #define blk_oldcop      cx_u.cx_blk.blku_oldcop
 170 #define blk_oldretsp    cx_u.cx_blk.blku_oldretsp
 171 #define blk_oldmarksp   cx_u.cx_blk.blku_oldmarksp
 172 #define blk_oldscopesp  cx_u.cx_blk.blku_oldscopesp
 173 #define blk_oldpm       cx_u.cx_blk.blku_oldpm
 174 #define blk_gimme       cx_u.cx_blk.blku_gimme
 175 #define blk_sub         cx_u.cx_blk.blk_u.blku_sub
 176 #define blk_eval        cx_u.cx_blk.blk_u.blku_eval
 177 #define blk_loop        cx_u.cx_blk.blk_u.blku_loop
 178
 179 /* Enter a block. */
 180 #define PUSHBLOCK(cx,t,sp) CXINC, cx = &cxstack[cxstack_ix],            \
 181         cx->cx_type             = t,                                    \
 182         cx->blk_oldsp           = sp - PL_stack_base,                   \
 183         cx->blk_oldcop          = PL_curcop,                            \
 184         cx->blk_oldmarksp       = PL_markstack_ptr - PL_markstack,              \
 185         cx->blk_oldscopesp      = PL_scopestack_ix,                     \
 186         cx->blk_oldretsp        = PL_retstack_ix,                               \
 187         cx->blk_oldpm           = PL_curpm,                             \
 188         cx->blk_gimme           = gimme;                                \
 189         DEBUG_l( PerlIO_printf(PerlIO_stderr(), "Entering block %ld, type %s\n",        \
 190                     (long)cxstack_ix, PL_block_type[t]); )
 191
 192 /* Exit a block (RETURN and LAST). */
 193 #define POPBLOCK(cx,pm) cx = &cxstack[cxstack_ix--],                    \
 194         newsp            = PL_stack_base + cx->blk_oldsp,                       \
 195         PL_curcop        = cx->blk_oldcop,                              \
 196         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
 197         PL_scopestack_ix = cx->blk_oldscopesp,                          \
 198         PL_retstack_ix   = cx->blk_oldretsp,                            \
 199         pm               = cx->blk_oldpm,                               \
 200         gimme            = cx->blk_gimme;                               \
 201         DEBUG_l( PerlIO_printf(PerlIO_stderr(), "Leaving block %ld, type %s\n",         \
 202                     (long)cxstack_ix+1,PL_block_type[CxTYPE(cx)]); )
 203
 204 /* Continue a block elsewhere (NEXT and REDO). */
 205 #define TOPBLOCK(cx) cx  = &cxstack[cxstack_ix],                        \
 206         PL_stack_sp      = PL_stack_base + cx->blk_oldsp,                       \
 207         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
 208         PL_scopestack_ix = cx->blk_oldscopesp,                          \
 209         PL_retstack_ix   = cx->blk_oldretsp,                            \
 210         PL_curpm         = cx->blk_oldpm
 211
 212 /* substitution context */
 213 struct subst {
 214     I32         sbu_iters;
 215     I32         sbu_maxiters;
 216     I32         sbu_rflags;
 217     I32         sbu_oldsave;
 218     bool        sbu_once;
 219     bool        sbu_rxtainted;
 220     char *      sbu_orig;
 221     SV *        sbu_dstr;
 222     SV *        sbu_targ;
 223     char *      sbu_s;
 224     char *      sbu_m;
 225     char *      sbu_strend;
 226     void *      sbu_rxres;
 227     REGEXP *    sbu_rx;
 228 };
 229 #define sb_iters        cx_u.cx_subst.sbu_iters
 230 #define sb_maxiters     cx_u.cx_subst.sbu_maxiters
 231 #define sb_rflags       cx_u.cx_subst.sbu_rflags
 232 #define sb_oldsave      cx_u.cx_subst.sbu_oldsave
 233 #define sb_once         cx_u.cx_subst.sbu_once
 234 #define sb_rxtainted    cx_u.cx_subst.sbu_rxtainted
 235 #define sb_orig         cx_u.cx_subst.sbu_orig
 236 #define sb_dstr         cx_u.cx_subst.sbu_dstr
 237 #define sb_targ         cx_u.cx_subst.sbu_targ
 238 #define sb_s            cx_u.cx_subst.sbu_s
 239 #define sb_m            cx_u.cx_subst.sbu_m
 240 #define sb_strend       cx_u.cx_subst.sbu_strend
 241 #define sb_rxres        cx_u.cx_subst.sbu_rxres
 242 #define sb_rx           cx_u.cx_subst.sbu_rx
 243
 244 #define PUSHSUBST(cx) CXINC, cx = &cxstack[cxstack_ix],                 \
 245         cx->sb_iters            = iters,                                \
 246         cx->sb_maxiters         = maxiters,                             \
 247         cx->sb_rflags           = r_flags,                              \
 248         cx->sb_oldsave          = oldsave,                              \
 249         cx->sb_once             = once,                                 \
 250         cx->sb_rxtainted        = rxtainted,                            \
 251         cx->sb_orig             = orig,                                 \
 252         cx->sb_dstr             = dstr,                                 \
 253         cx->sb_targ             = targ,                                 \
 254         cx->sb_s                = s,                                    \
 255         cx->sb_m                = m,                                    \
 256         cx->sb_strend           = strend,                               \
 257         cx->sb_rxres            = Null(void*),                          \
 258         cx->sb_rx               = rx,                                   \
 259         cx->cx_type             = CXt_SUBST;                            \
 260         rxres_save(&cx->sb_rxres, rx)
 261
 262 #define POPSUBST(cx) cx = &cxstack[cxstack_ix--];                       \
 263         rxres_free(&cx->sb_rxres)
 264
 265 struct context {
 266     U32         cx_type;        /* what kind of context this is */
 267     union {
 268         struct block    cx_blk;
 269         struct subst    cx_subst;
 270     } cx_u;
 271 };
 272
 273 #define CXTYPEMASK      0xff
 274 #define CXt_NULL        0
 275 #define CXt_SUB         1
 276 #define CXt_EVAL        2
 277 #define CXt_LOOP        3
 278 #define CXt_SUBST       4
 279 #define CXt_BLOCK       5
 280
 281 /* private flags for CXt_EVAL */
 282 #define CXp_REAL        0x00000100      /* truly eval'', not a lookalike */
 283
 284 #define CxTYPE(c)       ((c)->cx_type & CXTYPEMASK)
 285 #define CxREALEVAL(c)   (((c)->cx_type & (CXt_EVAL|CXp_REAL)) == (CXt_EVAL|CXp_REAL))
 286
 287 #define CXINC (cxstack_ix < cxstack_max ? ++cxstack_ix : (cxstack_ix = cxinc()))
 288
 289 /* "gimme" values */
 290 #define G_SCALAR        0
 291 #define G_ARRAY         1
 292 #define G_VOID          128     /* skip this bit when adding flags below */
 293
 294 /* extra flags for perl_call_* routines */
 295 #define G_DISCARD       2       /* Call FREETMPS. */
 296 #define G_EVAL          4       /* Assume eval {} around subroutine call. */
 297 #define G_NOARGS        8       /* Don't construct a @_ array. */
 298 #define G_KEEPERR      16       /* Append errors to $@, don't overwrite it */
 299 #define G_NODEBUG      32       /* Disable debugging at toplevel.  */
 300
 301 /* Support for switching (stack and block) contexts.
 302  * This ensures magic doesn't invalidate local stack and cx pointers.
 303  */
 304
 305 #define PERLSI_UNKNOWN          -1
 306 #define PERLSI_UNDEF            0
 307 #define PERLSI_MAIN             1
 308 #define PERLSI_MAGIC            2
 309 #define PERLSI_SORT             3
 310 #define PERLSI_SIGNAL           4
 311 #define PERLSI_OVERLOAD         5
 312 #define PERLSI_DESTROY          6
 313 #define PERLSI_WARNHOOK         7
 314 #define PERLSI_DIEHOOK          8
 315 #define PERLSI_REQUIRE          9
 316
 317 struct stackinfo {
 318     AV *                si_stack;       /* stack for current runlevel */
 319     PERL_CONTEXT *      si_cxstack;     /* context stack for runlevel */
 320     I32                 si_cxix;        /* current context index */
 321     I32                 si_cxmax;       /* maximum allocated index */
 322     I32                 si_type;        /* type of runlevel */
 323     struct stackinfo *  si_prev;
 324     struct stackinfo *  si_next;
 325     I32 *               si_markbase;    /* where markstack begins for us.
 326                                          * currently used only with DEBUGGING,
 327                                          * but not #ifdef-ed for bincompat */
 328 };
 329
 330 typedef struct stackinfo PERL_SI;
 331
 332 #define cxstack         (PL_curstackinfo->si_cxstack)
 333 #define cxstack_ix      (PL_curstackinfo->si_cxix)
 334 #define cxstack_max     (PL_curstackinfo->si_cxmax)
 335
 336 #ifdef DEBUGGING
 337 #  define       SET_MARKBASE PL_curstackinfo->si_markbase = PL_markstack_ptr
 338 #else
 339 #  define       SET_MARKBASE NOOP
 340 #endif
 341
 342 #define PUSHSTACKi(type) \
 343     STMT_START {                                                        \
 344         PERL_SI *next = PL_curstackinfo->si_next;                       \
 345         if (!next) {                                                    \
 346             next = new_stackinfo(32, 2048/sizeof(PERL_CONTEXT) - 1);    \
 347             next->si_prev = PL_curstackinfo;                            \
 348             PL_curstackinfo->si_next = next;                            \
 349         }                                                               \
 350         next->si_type = type;                                           \
 351         next->si_cxix = -1;                                             \
 352         AvFILLp(next->si_stack) = 0;                                    \
 353         SWITCHSTACK(PL_curstack,next->si_stack);                        \
 354         PL_curstackinfo = next;                                         \
 355         SET_MARKBASE;                                                   \
 356     } STMT_END
 357
 358 #define PUSHSTACK PUSHSTACKi(PERLSI_UNKNOWN)
 359
 360 /* POPSTACK works with PL_stack_sp, so it may need to be bracketed by
 361  * PUTBACK/SPAGAIN to flush/refresh any local SP that may be active */
 362 #define POPSTACK \
 363     STMT_START {                                                        \
 364         djSP;                                                           \
 365         PERL_SI *prev = PL_curstackinfo->si_prev;                       \
 366         if (!prev) {                                                    \
 367             PerlIO_printf(PerlIO_stderr(), "panic: POPSTACK\n");        \
 368             my_exit(1);                                                 \
 369         }                                                               \
 370         SWITCHSTACK(PL_curstack,prev->si_stack);                        \
 371         /* don't free prev here, free them all at the END{} */          \
 372         PL_curstackinfo = prev;                                         \
 373     } STMT_END
 374
 375 #define POPSTACK_TO(s) \
 376     STMT_START {                                                        \
 377         while (PL_curstack != s) {                                      \
 378             dounwind(-1);                                               \
 379             POPSTACK;                                                   \
 380         }                                                               \
 381     } STMT_END