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 };
  19
  20 #define Nullcop Null(COP*)
  21
  22 /*
  23  * Here we have some enormously heavy (or at least ponderous) wizardry.
  24  */
  25
  26 /* subroutine context */
  27 struct block_sub {
  28     CV *        cv;
  29     GV *        gv;
  30     GV *        dfoutgv;
  31 #ifndef USE_THREADS
  32     AV *        savearray;
  33 #endif /* USE_THREADS */
  34     AV *        argarray;
  35     U16         olddepth;
  36     U8          hasargs;
  37 };
  38
  39 #define PUSHSUB(cx)                                                     \
  40         cx->blk_sub.cv = cv;                                            \
  41         cx->blk_sub.olddepth = CvDEPTH(cv);                             \
  42         cx->blk_sub.hasargs = hasargs;
  43
  44 #define PUSHFORMAT(cx)                                                  \
  45         cx->blk_sub.cv = cv;                                            \
  46         cx->blk_sub.gv = gv;                                            \
  47         cx->blk_sub.hasargs = 0;                                        \
  48         cx->blk_sub.dfoutgv = PL_defoutgv;                              \
  49         (void)SvREFCNT_inc(cx->blk_sub.dfoutgv)
  50
  51 #define POPSUB(cx)                                                      \
  52         { struct block_sub cxsub;                                       \
  53           POPSUB1(cx);                                                  \
  54           POPSUB2(); }
  55
  56 #define POPSUB1(cx)                                                     \
  57         cxsub = cx->blk_sub;    /* because DESTROY may clobber *cx */
  58
  59 #ifdef USE_THREADS
  60 #define POPSAVEARRAY() NOOP
  61 #else
  62 #define POPSAVEARRAY()                                                  \
  63     STMT_START {                                                        \
  64         SvREFCNT_dec(GvAV(PL_defgv));                                   \
  65         GvAV(PL_defgv) = cxsub.savearray;                                       \
  66     } STMT_END
  67 #endif /* USE_THREADS */
  68
  69 #define POPSUB2()                                                       \
  70         if (cxsub.hasargs) {                                            \
  71             POPSAVEARRAY();                                             \
  72             /* destroy arg array */                                     \
  73             av_clear(cxsub.argarray);                                   \
  74             AvREAL_off(cxsub.argarray);                                 \
  75         }                                                               \
  76         if (cxsub.cv) {                                                 \
  77             if (!(CvDEPTH(cxsub.cv) = cxsub.olddepth))                  \
  78                 SvREFCNT_dec(cxsub.cv);                                 \
  79         }
  80
  81 #define POPFORMAT(cx)                                                   \
  82         setdefout(cx->blk_sub.dfoutgv);                                 \
  83         SvREFCNT_dec(cx->blk_sub.dfoutgv);
  84
  85 /* eval context */
  86 struct block_eval {
  87     I32         old_in_eval;
  88     I32         old_op_type;
  89     char *      old_name;
  90     OP *        old_eval_root;
  91     SV *        cur_text;
  92 };
  93
  94 #define PUSHEVAL(cx,n,fgv)                                              \
  95         cx->blk_eval.old_in_eval = PL_in_eval;                          \
  96         cx->blk_eval.old_op_type = PL_op->op_type;                              \
  97         cx->blk_eval.old_name = n;                                      \
  98         cx->blk_eval.old_eval_root = PL_eval_root;                              \
  99         cx->blk_eval.cur_text = PL_linestr;
 100
 101 #define POPEVAL(cx)                                                     \
 102         PL_in_eval = cx->blk_eval.old_in_eval;                          \
 103         optype = cx->blk_eval.old_op_type;                              \
 104         PL_eval_root = cx->blk_eval.old_eval_root;
 105
 106 /* loop context */
 107 struct block_loop {
 108     char *      label;
 109     I32         resetsp;
 110     OP *        redo_op;
 111     OP *        next_op;
 112     OP *        last_op;
 113     SV **       itervar;
 114     SV *        itersave;
 115     SV *        iterlval;
 116     AV *        iterary;
 117     IV          iterix;
 118     IV          itermax;
 119 };
 120
 121 #define PUSHLOOP(cx, ivar, s)                                           \
 122         cx->blk_loop.label = PL_curcop->cop_label;                              \
 123         cx->blk_loop.resetsp = s - PL_stack_base;                               \
 124         cx->blk_loop.redo_op = cLOOP->op_redoop;                        \
 125         cx->blk_loop.next_op = cLOOP->op_nextop;                        \
 126         cx->blk_loop.last_op = cLOOP->op_lastop;                        \
 127         if (cx->blk_loop.itervar = (ivar))                              \
 128             cx->blk_loop.itersave = SvREFCNT_inc(*cx->blk_loop.itervar);\
 129         cx->blk_loop.iterlval = Nullsv;                                 \
 130         cx->blk_loop.iterary = Nullav;                                  \
 131         cx->blk_loop.iterix = -1;
 132
 133 #define POPLOOP(cx)                                                     \
 134         { struct block_loop cxloop;                                     \
 135           POPLOOP1(cx);                                                 \
 136           POPLOOP2(); }
 137
 138 #define POPLOOP1(cx)                                                    \
 139         cxloop = cx->blk_loop;  /* because DESTROY may clobber *cx */   \
 140         newsp = PL_stack_base + cxloop.resetsp;
 141
 142 #define POPLOOP2()                                                      \
 143         SvREFCNT_dec(cxloop.iterlval);                                  \
 144         if (cxloop.itervar) {                                           \
 145             SvREFCNT_dec(*cxloop.itervar);                              \
 146             *cxloop.itervar = cxloop.itersave;                          \
 147         }                                                               \
 148         if (cxloop.iterary && cxloop.iterary != PL_curstack)            \
 149             SvREFCNT_dec(cxloop.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(PerlIO_stderr(), "Entering block %ld, type %s\n",        \
 189                     (long)cxstack_ix, block_type[t]); )
 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(PerlIO_stderr(), "Leaving block %ld, type %s\n",         \
 201                     (long)cxstack_ix+1,block_type[cx->cx_type]); )
 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
 210 /* substitution context */
 211 struct subst {
 212     I32         sbu_iters;
 213     I32         sbu_maxiters;
 214     I32         sbu_safebase;
 215     I32         sbu_oldsave;
 216     bool        sbu_once;
 217     bool        sbu_rxtainted;
 218     char *      sbu_orig;
 219     SV *        sbu_dstr;
 220     SV *        sbu_targ;
 221     char *      sbu_s;
 222     char *      sbu_m;
 223     char *      sbu_strend;
 224     void *      sbu_rxres;
 225     REGEXP *    sbu_rx;
 226 };
 227 #define sb_iters        cx_u.cx_subst.sbu_iters
 228 #define sb_maxiters     cx_u.cx_subst.sbu_maxiters
 229 #define sb_safebase     cx_u.cx_subst.sbu_safebase
 230 #define sb_oldsave      cx_u.cx_subst.sbu_oldsave
 231 #define sb_once         cx_u.cx_subst.sbu_once
 232 #define sb_rxtainted    cx_u.cx_subst.sbu_rxtainted
 233 #define sb_orig         cx_u.cx_subst.sbu_orig
 234 #define sb_dstr         cx_u.cx_subst.sbu_dstr
 235 #define sb_targ         cx_u.cx_subst.sbu_targ
 236 #define sb_s            cx_u.cx_subst.sbu_s
 237 #define sb_m            cx_u.cx_subst.sbu_m
 238 #define sb_strend       cx_u.cx_subst.sbu_strend
 239 #define sb_rxres        cx_u.cx_subst.sbu_rxres
 240 #define sb_rx           cx_u.cx_subst.sbu_rx
 241
 242 #define PUSHSUBST(cx) CXINC, cx = &cxstack[cxstack_ix],                 \
 243         cx->sb_iters            = iters,                                \
 244         cx->sb_maxiters         = maxiters,                             \
 245         cx->sb_safebase         = safebase,                             \
 246         cx->sb_oldsave          = oldsave,                              \
 247         cx->sb_once             = once,                                 \
 248         cx->sb_rxtainted        = rxtainted,                            \
 249         cx->sb_orig             = orig,                                 \
 250         cx->sb_dstr             = dstr,                                 \
 251         cx->sb_targ             = targ,                                 \
 252         cx->sb_s                = s,                                    \
 253         cx->sb_m                = m,                                    \
 254         cx->sb_strend           = strend,                               \
 255         cx->sb_rxres            = Null(void*),                          \
 256         cx->sb_rx               = rx,                                   \
 257         cx->cx_type             = CXt_SUBST;                            \
 258         rxres_save(&cx->sb_rxres, rx)
 259
 260 #define POPSUBST(cx) cx = &cxstack[cxstack_ix--];                       \
 261         rxres_free(&cx->sb_rxres)
 262
 263 struct context {
 264     I32         cx_type;        /* what kind of context this is */
 265     union {
 266         struct block    cx_blk;
 267         struct subst    cx_subst;
 268     } cx_u;
 269 };
 270 #define CXt_NULL        0
 271 #define CXt_SUB         1
 272 #define CXt_EVAL        2
 273 #define CXt_LOOP        3
 274 #define CXt_SUBST       4
 275 #define CXt_BLOCK       5
 276
 277 #define CXINC (cxstack_ix < cxstack_max ? ++cxstack_ix : (cxstack_ix = cxinc()))
 278
 279 /* "gimme" values */
 280 #define G_SCALAR        0
 281 #define G_ARRAY         1
 282 #define G_VOID          128     /* skip this bit when adding flags below */
 283
 284 /* extra flags for perl_call_* routines */
 285 #define G_DISCARD       2       /* Call FREETMPS. */
 286 #define G_EVAL          4       /* Assume eval {} around subroutine call. */
 287 #define G_NOARGS        8       /* Don't construct a @_ array. */
 288 #define G_KEEPERR      16       /* Append errors to $@, don't overwrite it */
 289 #define G_NODEBUG      32       /* Disable debugging at toplevel.  */
 290
 291 /* Support for switching (stack and block) contexts.
 292  * This ensures magic doesn't invalidate local stack and cx pointers.
 293  */
 294
 295 #define PERLSI_UNKNOWN          -1
 296 #define PERLSI_UNDEF            0
 297 #define PERLSI_MAIN             1
 298 #define PERLSI_MAGIC            2
 299 #define PERLSI_SORT             3
 300 #define PERLSI_SIGNAL           4
 301 #define PERLSI_OVERLOAD         5
 302 #define PERLSI_DESTROY          6
 303 #define PERLSI_WARNHOOK         7
 304 #define PERLSI_DIEHOOK          8
 305 #define PERLSI_REQUIRE          9
 306
 307 struct stackinfo {
 308     AV *                si_stack;       /* stack for current runlevel */
 309     PERL_CONTEXT *      si_cxstack;     /* context stack for runlevel */
 310     I32                 si_cxix;        /* current context index */
 311     I32                 si_cxmax;       /* maximum allocated index */
 312     I32                 si_type;        /* type of runlevel */
 313     struct stackinfo *  si_prev;
 314     struct stackinfo *  si_next;
 315     I32 *               si_markbase;    /* where markstack begins for us.
 316                                          * currently used only with DEBUGGING,
 317                                          * but not #ifdef-ed for bincompat */
 318 };
 319
 320 typedef struct stackinfo PERL_SI;
 321
 322 #define cxstack         (PL_curstackinfo->si_cxstack)
 323 #define cxstack_ix      (PL_curstackinfo->si_cxix)
 324 #define cxstack_max     (PL_curstackinfo->si_cxmax)
 325
 326 #ifdef DEBUGGING
 327 #  define       SET_MARKBASE PL_curstackinfo->si_markbase = PL_markstack_ptr
 328 #else
 329 #  define       SET_MARKBASE NOOP
 330 #endif
 331
 332 #define PUSHSTACKi(type) \
 333     STMT_START {                                                        \
 334         PERL_SI *next = PL_curstackinfo->si_next;                       \
 335         if (!next) {                                                    \
 336             next = new_stackinfo(32, 2048/sizeof(PERL_CONTEXT) - 1);    \
 337             next->si_prev = PL_curstackinfo;                            \
 338             PL_curstackinfo->si_next = next;                            \
 339         }                                                               \
 340         next->si_type = type;                                           \
 341         next->si_cxix = -1;                                             \
 342         AvFILLp(next->si_stack) = 0;                                    \
 343         SWITCHSTACK(PL_curstack,next->si_stack);                        \
 344         PL_curstackinfo = next;                                         \
 345         SET_MARKBASE;                                                   \
 346     } STMT_END
 347
 348 #define PUSHSTACK PUSHSTACKi(PERLSI_UNKNOWN)
 349
 350 #define POPSTACK \
 351     STMT_START {                                                        \
 352         PERL_SI *prev = PL_curstackinfo->si_prev;                       \
 353         if (!prev) {                                                    \
 354             PerlIO_printf(PerlIO_stderr(), "panic: POPSTACK\n");        \
 355             my_exit(1);                                                 \
 356         }                                                               \
 357         SWITCHSTACK(PL_curstack,prev->si_stack);                        \
 358         /* don't free prev here, free them all at the END{} */          \
 359         PL_curstackinfo = prev;                                         \
 360     } STMT_END
 361
 362 #define POPSTACK_TO(s) \
 363     STMT_START {                                                        \
 364         while (PL_curstack != s) {                                      \
 365             dounwind(-1);                                               \
 366             POPSTACK;                                                   \
 367         }                                                               \
 368     } STMT_END