cop.h

   1 /* $RCSfile: cmd.h,v $$Revision: 4.1 $$Date: 92/08/07 17:19:19 $
   2  *
   3  *    Copyright (c) 1991, 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  * $Log:        cmd.h,v $
   9  * Revision 4.1  92/08/07  17:19:19  lwall
  10  * Stage 6 Snapshot
  11  *
  12  * Revision 4.0.1.2  92/06/08  12:01:02  lwall
  13  * patch20: removed implicit int declarations on funcions
  14  *
  15  * Revision 4.0.1.1  91/06/07  10:28:50  lwall
  16  * patch4: new copyright notice
  17  * patch4: length($`), length($&), length($') now optimized to avoid string copy
  18  *
  19  * Revision 4.0  91/03/20  01:04:34  lwall
  20  * 4.0 baseline.
  21  *
  22  */
  23
  24 struct acop {
  25     GV          *acop_gv;       /* a symbol table entry */
  26     OP          *acop_expr;     /* any associated expression */
  27 };
  28
  29 struct ccop {
  30     OP          *ccop_true;     /* normal code to do on if and while */
  31     OP          *ccop_alt;      /* else cmd ptr or continue code */
  32 };
  33
  34 struct scop {
  35     OP          **scop_next;    /* array of pointers to commands */
  36     short       scop_offset;    /* first value - 1 */
  37     short       scop_max;       /* last value + 1 */
  38 };
  39
  40 struct cop {
  41     BASEOP
  42     OP          *cop_expr;      /* conditional expression */
  43     OP          *cop_head;      /* head of this command list */
  44     SV          *cop_short;     /* string to match as shortcut */
  45     GV          *cop_gv;        /* a symbol table entry, mostly for fp */
  46     char        *cop_label;     /* label for this construct */
  47     union uop {
  48         struct acop acop;       /* normal command */
  49         struct ccop ccop;       /* compound command */
  50         struct scop scop;       /* switch command */
  51     } uop;
  52     U32         cop_seq;        /* parse sequence number */
  53     short       cop_slen;       /* len of cop_short, if not null */
  54     VOL short   cop_flags;      /* optimization flags--see above */
  55     HV *        cop_stash;      /* package line was compiled in */
  56     GV *        cop_filegv;     /* file the following line # is from */
  57     line_t      cop_line;       /* line # of this command */
  58     char        cop_type;       /* what this command does */
  59 };
  60
  61 #define Nullcop Null(COP*)
  62
  63 /*
  64  * Here we have some enormously heavy (or at least ponderous) wizardry.
  65  */
  66
  67 /* subroutine context */
  68 struct block_sub {
  69     CV *        cv;
  70     GV *        gv;
  71     GV *        dfoutgv;
  72     AV *        savearray;
  73     AV *        argarray;
  74     U16         olddepth;
  75     U8          hasargs;
  76 };
  77
  78 #define PUSHSUB(cx)                                                     \
  79         cx->blk_sub.cv = cv;                                            \
  80         cx->blk_sub.olddepth = CvDEPTH(cv);                             \
  81         cx->blk_sub.hasargs = hasargs;
  82
  83 #define PUSHFORMAT(cx)                                                  \
  84         cx->blk_sub.cv = cv;                                            \
  85         cx->blk_sub.gv = gv;                                            \
  86         cx->blk_sub.dfoutgv = defoutgv;                                 \
  87         cx->blk_sub.hasargs = 0;
  88
  89 #define POPSUB(cx)                                                      \
  90         if (cx->blk_sub.hasargs) {   /* put back old @_ */              \
  91             GvAV(defgv) = cx->blk_sub.savearray;                        \
  92         }                                                               \
  93         if (cx->blk_sub.cv) {                                           \
  94             if (!(CvDEPTH(cx->blk_sub.cv) = cx->blk_sub.olddepth)) {    \
  95                 if (CvDELETED(cx->blk_sub.cv))                          \
  96                     SvREFCNT_dec((SV*)cx->blk_sub.cv);                  \
  97             }                                                           \
  98         }
  99
 100 #define POPFORMAT(cx)                                                   \
 101         defoutgv = cx->blk_sub.dfoutgv;
 102
 103 /* eval context */
 104 struct block_eval {
 105     I32         old_in_eval;
 106     I32         old_op_type;
 107     char *      old_name;
 108     OP *        old_eval_root;
 109 };
 110
 111 #define PUSHEVAL(cx,n,fgv)                                              \
 112         cx->blk_eval.old_in_eval = in_eval;                             \
 113         cx->blk_eval.old_op_type = op->op_type;                         \
 114         cx->blk_eval.old_name = n;                                      \
 115         cx->blk_eval.old_eval_root = eval_root;
 116
 117 #define POPEVAL(cx)                                                     \
 118         in_eval = cx->blk_eval.old_in_eval;                             \
 119         optype = cx->blk_eval.old_op_type;                              \
 120         eval_root = cx->blk_eval.old_eval_root;
 121
 122 /* loop context */
 123 struct block_loop {
 124     char *      label;
 125     I32         resetsp;
 126     OP *        redo_op;
 127     OP *        next_op;
 128     OP *        last_op;
 129     SV **       itervar;
 130     SV *        itersave;
 131     AV *        iterary;
 132     I32         iterix;
 133 };
 134
 135 #define PUSHLOOP(cx, ivar, s)                                           \
 136         cx->blk_loop.label = curcop->cop_label;                         \
 137         cx->blk_loop.resetsp = s - stack_base;                          \
 138         cx->blk_loop.redo_op = cLOOP->op_redoop;                        \
 139         cx->blk_loop.next_op = cLOOP->op_nextop;                        \
 140         cx->blk_loop.last_op = cLOOP->op_lastop;                        \
 141         cx->blk_loop.itervar = ivar;                                    \
 142         if (ivar)                                                       \
 143             cx->blk_loop.itersave = *cx->blk_loop.itervar;
 144
 145 #define POPLOOP(cx)                                                     \
 146         newsp           = stack_base + cx->blk_loop.resetsp;            \
 147         if (cx->blk_loop.itervar)                                       \
 148             *cx->blk_loop.itervar = cx->blk_loop.itersave;
 149
 150 /* context common to subroutines, evals and loops */
 151 struct block {
 152     I32         blku_oldsp;     /* stack pointer to copy stuff down to */
 153     COP *       blku_oldcop;    /* old curcop pointer */
 154     I32         blku_oldretsp;  /* return stack index */
 155     I32         blku_oldmarksp; /* mark stack index */
 156     I32         blku_oldscopesp;        /* scope stack index */
 157     PMOP *      blku_oldpm;     /* values of pattern match vars */
 158     U8          blku_gimme;     /* is this block running in list context? */
 159
 160     union {
 161         struct block_sub        blku_sub;
 162         struct block_eval       blku_eval;
 163         struct block_loop       blku_loop;
 164     } blk_u;
 165 };
 166 #define blk_oldsp       cx_u.cx_blk.blku_oldsp
 167 #define blk_oldcop      cx_u.cx_blk.blku_oldcop
 168 #define blk_oldretsp    cx_u.cx_blk.blku_oldretsp
 169 #define blk_oldmarksp   cx_u.cx_blk.blku_oldmarksp
 170 #define blk_oldscopesp  cx_u.cx_blk.blku_oldscopesp
 171 #define blk_oldpm       cx_u.cx_blk.blku_oldpm
 172 #define blk_gimme       cx_u.cx_blk.blku_gimme
 173 #define blk_sub         cx_u.cx_blk.blk_u.blku_sub
 174 #define blk_eval        cx_u.cx_blk.blk_u.blku_eval
 175 #define blk_loop        cx_u.cx_blk.blk_u.blku_loop
 176
 177 /* Enter a block. */
 178 #define PUSHBLOCK(cx,t,sp) CXINC, cx = &cxstack[cxstack_ix],            \
 179         cx->cx_type             = t,                                    \
 180         cx->blk_oldsp           = sp - stack_base,                      \
 181         cx->blk_oldcop          = curcop,                               \
 182         cx->blk_oldmarksp       = markstack_ptr - markstack,            \
 183         cx->blk_oldscopesp      = scopestack_ix,                        \
 184         cx->blk_oldretsp        = retstack_ix,                          \
 185         cx->blk_oldpm           = curpm,                                \
 186         cx->blk_gimme           = gimme;                                \
 187         DEBUG_l( fprintf(stderr,"Entering block %d, type %s\n",         \
 188                     cxstack_ix, block_type[t]); )
 189
 190 /* Exit a block (RETURN and LAST). */
 191 #define POPBLOCK(cx) cx = &cxstack[cxstack_ix--],                       \
 192         newsp           = stack_base + cx->blk_oldsp,                   \
 193         curcop          = cx->blk_oldcop,                               \
 194         markstack_ptr   = markstack + cx->blk_oldmarksp,                \
 195         scopestack_ix   = cx->blk_oldscopesp,                           \
 196         retstack_ix     = cx->blk_oldretsp,                             \
 197         curpm           = cx->blk_oldpm,                                \
 198         gimme           = cx->blk_gimme;                                \
 199         DEBUG_l( fprintf(stderr,"Leaving block %d, type %s\n",          \
 200                     cxstack_ix+1,block_type[cx->cx_type]); )
 201
 202 /* Continue a block elsewhere (NEXT and REDO). */
 203 #define TOPBLOCK(cx) cx = &cxstack[cxstack_ix],                         \
 204         stack_sp        = stack_base + cx->blk_oldsp,                   \
 205         markstack_ptr   = markstack + cx->blk_oldmarksp,                \
 206         scopestack_ix   = cx->blk_oldscopesp,                           \
 207         retstack_ix     = cx->blk_oldretsp
 208
 209 /* substitution context */
 210 struct subst {
 211     I32         sbu_iters;
 212     I32         sbu_maxiters;
 213     I32         sbu_safebase;
 214     I32         sbu_once;
 215     char *      sbu_orig;
 216     SV *        sbu_dstr;
 217     SV *        sbu_targ;
 218     char *      sbu_s;
 219     char *      sbu_m;
 220     char *      sbu_strend;
 221     char *      sbu_subbase;
 222 };
 223 #define sb_iters        cx_u.cx_subst.sbu_iters
 224 #define sb_maxiters     cx_u.cx_subst.sbu_maxiters
 225 #define sb_safebase     cx_u.cx_subst.sbu_safebase
 226 #define sb_once         cx_u.cx_subst.sbu_once
 227 #define sb_orig         cx_u.cx_subst.sbu_orig
 228 #define sb_dstr         cx_u.cx_subst.sbu_dstr
 229 #define sb_targ         cx_u.cx_subst.sbu_targ
 230 #define sb_s            cx_u.cx_subst.sbu_s
 231 #define sb_m            cx_u.cx_subst.sbu_m
 232 #define sb_strend       cx_u.cx_subst.sbu_strend
 233 #define sb_subbase      cx_u.cx_subst.sbu_subbase
 234
 235 #define PUSHSUBST(cx) CXINC, cx = &cxstack[cxstack_ix],                 \
 236         cx->sb_iters            = iters,                                \
 237         cx->sb_maxiters         = maxiters,                             \
 238         cx->sb_safebase         = safebase,                             \
 239         cx->sb_once             = once,                                 \
 240         cx->sb_orig             = orig,                                 \
 241         cx->sb_dstr             = dstr,                                 \
 242         cx->sb_targ             = targ,                                 \
 243         cx->sb_s                = s,                                    \
 244         cx->sb_m                = m,                                    \
 245         cx->sb_strend           = strend,                               \
 246         cx->cx_type             = CXt_SUBST
 247
 248 #define POPSUBST(cx) cxstack_ix--
 249
 250 struct context {
 251     I32         cx_type;        /* what kind of context this is */
 252     union {
 253         struct block    cx_blk;
 254         struct subst    cx_subst;
 255     } cx_u;
 256 };
 257 #define CXt_NULL        0
 258 #define CXt_SUB         1
 259 #define CXt_EVAL        2
 260 #define CXt_LOOP        3
 261 #define CXt_SUBST       4
 262 #define CXt_BLOCK       5
 263
 264 #define CXINC (cxstack_ix < cxstack_max ? ++cxstack_ix : (cxstack_ix = cxinc()))
 265
 266 /* "gimme" values */
 267 #define G_SCALAR 0
 268 #define G_ARRAY 1
 269