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/cvs/cvsroot/staticperl/perl/cop.h
Revision: 1.1
Committed: Thu Jun 30 14:26:41 2005 UTC (21 years, 3 months ago) by root
Content type: text/plain
Branch: MAIN
CVS Tags: PERL-5-8-7, HEAD
Branch point for: PERL
Log Message:
*** empty log message ***

File Contents

# User Rev Content
1 root 1.1 /* cop.h
2     *
3     * Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
4     * 2000, 2001, 2002, 2003, 2004, by Larry Wall and others
5     *
6     * You may distribute under the terms of either the GNU General Public
7     * License or the Artistic License, as specified in the README file.
8     *
9     * Control ops (cops) are one of the three ops OP_NEXTSTATE, OP_DBSTATE,
10     * and OP_SETSTATE that (loosely speaking) are separate statements.
11     * They hold information important for lexical state and error reporting.
12     * At run time, PL_curcop is set to point to the most recently executed cop,
13     * and thus can be used to determine our current state.
14     */
15    
16     struct cop {
17     BASEOP
18     char * cop_label; /* label for this construct */
19     #ifdef USE_ITHREADS
20     char * cop_stashpv; /* package line was compiled in */
21     char * cop_file; /* file name the following line # is from */
22     #else
23     HV * cop_stash; /* package line was compiled in */
24     GV * cop_filegv; /* file the following line # is from */
25     #endif
26     U32 cop_seq; /* parse sequence number */
27     I32 cop_arybase; /* array base this line was compiled with */
28     line_t cop_line; /* line # of this command */
29     SV * cop_warnings; /* lexical warnings bitmask */
30     SV * cop_io; /* lexical IO defaults */
31     };
32    
33     #define Nullcop Null(COP*)
34    
35     #ifdef USE_ITHREADS
36     # define CopFILE(c) ((c)->cop_file)
37     # define CopFILEGV(c) (CopFILE(c) \
38     ? gv_fetchfile(CopFILE(c)) : Nullgv)
39    
40     # ifdef NETWARE
41     # define CopFILE_set(c,pv) ((c)->cop_file = savepv(pv))
42     # else
43     # define CopFILE_set(c,pv) ((c)->cop_file = savesharedpv(pv))
44     # endif
45    
46     # define CopFILESV(c) (CopFILE(c) \
47     ? GvSV(gv_fetchfile(CopFILE(c))) : Nullsv)
48     # define CopFILEAV(c) (CopFILE(c) \
49     ? GvAV(gv_fetchfile(CopFILE(c))) : Nullav)
50     # define CopSTASHPV(c) ((c)->cop_stashpv)
51    
52     # ifdef NETWARE
53     # define CopSTASHPV_set(c,pv) ((c)->cop_stashpv = ((pv) ? savepv(pv) : Nullch))
54     # else
55     # define CopSTASHPV_set(c,pv) ((c)->cop_stashpv = savesharedpv(pv))
56     # endif
57    
58     # define CopSTASH(c) (CopSTASHPV(c) \
59     ? gv_stashpv(CopSTASHPV(c),GV_ADD) : Nullhv)
60     # define CopSTASH_set(c,hv) CopSTASHPV_set(c, (hv) ? HvNAME(hv) : Nullch)
61     # define CopSTASH_eq(c,hv) ((hv) \
62     && (CopSTASHPV(c) == HvNAME(hv) \
63     || (CopSTASHPV(c) && HvNAME(hv) \
64     && strEQ(CopSTASHPV(c), HvNAME(hv)))))
65     # ifdef NETWARE
66     # define CopSTASH_free(c) SAVECOPSTASH_FREE(c)
67     # else
68     # define CopSTASH_free(c) PerlMemShared_free(CopSTASHPV(c))
69     # endif
70    
71     # ifdef NETWARE
72     # define CopFILE_free(c) SAVECOPFILE_FREE(c)
73     # else
74     # define CopFILE_free(c) (PerlMemShared_free(CopFILE(c)),(CopFILE(c) = Nullch))
75     # endif
76     #else
77     # define CopFILEGV(c) ((c)->cop_filegv)
78     # define CopFILEGV_set(c,gv) ((c)->cop_filegv = (GV*)SvREFCNT_inc(gv))
79     # define CopFILE_set(c,pv) CopFILEGV_set((c), gv_fetchfile(pv))
80     # define CopFILESV(c) (CopFILEGV(c) ? GvSV(CopFILEGV(c)) : Nullsv)
81     # define CopFILEAV(c) (CopFILEGV(c) ? GvAV(CopFILEGV(c)) : Nullav)
82     # define CopFILE(c) (CopFILESV(c) ? SvPVX(CopFILESV(c)) : Nullch)
83     # define CopSTASH(c) ((c)->cop_stash)
84     # define CopSTASH_set(c,hv) ((c)->cop_stash = (hv))
85     # define CopSTASHPV(c) (CopSTASH(c) ? HvNAME(CopSTASH(c)) : Nullch)
86     /* cop_stash is not refcounted */
87     # define CopSTASHPV_set(c,pv) CopSTASH_set((c), gv_stashpv(pv,GV_ADD))
88     # define CopSTASH_eq(c,hv) (CopSTASH(c) == (hv))
89     # define CopSTASH_free(c)
90     # define CopFILE_free(c) (SvREFCNT_dec(CopFILEGV(c)),(CopFILEGV(c) = Nullgv))
91    
92     #endif /* USE_ITHREADS */
93    
94     #define CopSTASH_ne(c,hv) (!CopSTASH_eq(c,hv))
95     #define CopLINE(c) ((c)->cop_line)
96     #define CopLINE_inc(c) (++CopLINE(c))
97     #define CopLINE_dec(c) (--CopLINE(c))
98     #define CopLINE_set(c,l) (CopLINE(c) = (l))
99    
100     /* OutCopFILE() is CopFILE for output (caller, die, warn, etc.) */
101     #ifdef MACOS_TRADITIONAL
102     # define OutCopFILE(c) MacPerl_MPWFileName(CopFILE(c))
103     #else
104     # define OutCopFILE(c) CopFILE(c)
105     #endif
106    
107     /*
108     * Here we have some enormously heavy (or at least ponderous) wizardry.
109     */
110    
111     /* subroutine context */
112     struct block_sub {
113     CV * cv;
114     GV * gv;
115     GV * dfoutgv;
116     #ifndef USE_5005THREADS
117     AV * savearray;
118     #endif /* USE_5005THREADS */
119     AV * argarray;
120     long olddepth;
121     U8 hasargs;
122     U8 lval; /* XXX merge lval and hasargs? */
123     PAD *oldcomppad;
124     };
125    
126     /* base for the next two macros. Don't use directly.
127     * Note that the refcnt of the cv is incremented twice; The CX one is
128     * decremented by LEAVESUB, the other by LEAVE. */
129    
130     #define PUSHSUB_BASE(cx) \
131     cx->blk_sub.cv = cv; \
132     cx->blk_sub.olddepth = CvDEPTH(cv); \
133     cx->blk_sub.hasargs = hasargs; \
134     if (!CvDEPTH(cv)) { \
135     (void)SvREFCNT_inc(cv); \
136     (void)SvREFCNT_inc(cv); \
137     SAVEFREESV(cv); \
138     }
139    
140    
141     #define PUSHSUB(cx) \
142     PUSHSUB_BASE(cx) \
143     cx->blk_sub.lval = PL_op->op_private & \
144     (OPpLVAL_INTRO|OPpENTERSUB_INARGS);
145    
146     /* variant for use by OP_DBSTATE, where op_private holds hint bits */
147     #define PUSHSUB_DB(cx) \
148     PUSHSUB_BASE(cx) \
149     cx->blk_sub.lval = 0;
150    
151    
152     #define PUSHFORMAT(cx) \
153     cx->blk_sub.cv = cv; \
154     cx->blk_sub.gv = gv; \
155     cx->blk_sub.hasargs = 0; \
156     cx->blk_sub.dfoutgv = PL_defoutgv; \
157     (void)SvREFCNT_inc(cx->blk_sub.dfoutgv)
158    
159     #ifdef USE_5005THREADS
160     # define POP_SAVEARRAY() NOOP
161     #else
162     # define POP_SAVEARRAY() \
163     STMT_START { \
164     SvREFCNT_dec(GvAV(PL_defgv)); \
165     GvAV(PL_defgv) = cx->blk_sub.savearray; \
166     } STMT_END
167     #endif /* USE_5005THREADS */
168    
169     /* junk in @_ spells trouble when cloning CVs and in pp_caller(), so don't
170     * leave any (a fast av_clear(ary), basically) */
171     #define CLEAR_ARGARRAY(ary) \
172     STMT_START { \
173     AvMAX(ary) += AvARRAY(ary) - AvALLOC(ary); \
174     SvPVX(ary) = (char*)AvALLOC(ary); \
175     AvFILLp(ary) = -1; \
176     } STMT_END
177    
178     #define POPSUB(cx,sv) \
179     STMT_START { \
180     if (cx->blk_sub.hasargs) { \
181     POP_SAVEARRAY(); \
182     /* abandon @_ if it got reified */ \
183     if (AvREAL(cx->blk_sub.argarray)) { \
184     SSize_t fill = AvFILLp(cx->blk_sub.argarray); \
185     SvREFCNT_dec(cx->blk_sub.argarray); \
186     cx->blk_sub.argarray = newAV(); \
187     av_extend(cx->blk_sub.argarray, fill); \
188     AvFLAGS(cx->blk_sub.argarray) = AVf_REIFY; \
189     CX_CURPAD_SV(cx->blk_sub, 0) = (SV*)cx->blk_sub.argarray; \
190     } \
191     else { \
192     CLEAR_ARGARRAY(cx->blk_sub.argarray); \
193     } \
194     } \
195     sv = (SV*)cx->blk_sub.cv; \
196     if (sv && (CvDEPTH((CV*)sv) = cx->blk_sub.olddepth)) \
197     sv = Nullsv; \
198     } STMT_END
199    
200     #define LEAVESUB(sv) \
201     STMT_START { \
202     if (sv) \
203     SvREFCNT_dec(sv); \
204     } STMT_END
205    
206     #define POPFORMAT(cx) \
207     setdefout(cx->blk_sub.dfoutgv); \
208     SvREFCNT_dec(cx->blk_sub.dfoutgv);
209    
210     /* eval context */
211     struct block_eval {
212     I32 old_in_eval;
213     I32 old_op_type;
214     SV * old_namesv;
215     OP * old_eval_root;
216     SV * cur_text;
217     CV * cv;
218     };
219    
220     #define PUSHEVAL(cx,n,fgv) \
221     STMT_START { \
222     cx->blk_eval.old_in_eval = PL_in_eval; \
223     cx->blk_eval.old_op_type = PL_op->op_type; \
224     cx->blk_eval.old_namesv = (n ? newSVpv(n,0) : Nullsv); \
225     cx->blk_eval.old_eval_root = PL_eval_root; \
226     cx->blk_eval.cur_text = PL_linestr; \
227     cx->blk_eval.cv = Nullcv; /* set by doeval(), as applicable */ \
228     } STMT_END
229    
230     #define POPEVAL(cx) \
231     STMT_START { \
232     PL_in_eval = cx->blk_eval.old_in_eval; \
233     optype = cx->blk_eval.old_op_type; \
234     PL_eval_root = cx->blk_eval.old_eval_root; \
235     if (cx->blk_eval.old_namesv) \
236     sv_2mortal(cx->blk_eval.old_namesv); \
237     } STMT_END
238    
239     /* loop context */
240     struct block_loop {
241     char * label;
242     I32 resetsp;
243     OP * redo_op;
244     OP * next_op;
245     OP * last_op;
246     #ifdef USE_ITHREADS
247     void * iterdata;
248     PAD *oldcomppad;
249     #else
250     SV ** itervar;
251     #endif
252     SV * itersave;
253     SV * iterlval;
254     AV * iterary;
255     IV iterix;
256     IV itermax;
257     };
258    
259     #ifdef USE_ITHREADS
260     # define CxITERVAR(c) \
261     ((c)->blk_loop.iterdata \
262     ? (CxPADLOOP(cx) \
263     ? &CX_CURPAD_SV( (c)->blk_loop, \
264     INT2PTR(PADOFFSET, (c)->blk_loop.iterdata)) \
265     : &GvSV((GV*)(c)->blk_loop.iterdata)) \
266     : (SV**)NULL)
267     # define CX_ITERDATA_SET(cx,idata) \
268     CX_CURPAD_SAVE(cx->blk_loop); \
269     if ((cx->blk_loop.iterdata = (idata))) \
270     cx->blk_loop.itersave = SvREFCNT_inc(*CxITERVAR(cx)); \
271     else \
272     cx->blk_loop.itersave = Nullsv;
273     #else
274     # define CxITERVAR(c) ((c)->blk_loop.itervar)
275     # define CX_ITERDATA_SET(cx,ivar) \
276     if ((cx->blk_loop.itervar = (SV**)(ivar))) \
277     cx->blk_loop.itersave = SvREFCNT_inc(*CxITERVAR(cx)); \
278     else \
279     cx->blk_loop.itersave = Nullsv;
280     #endif
281    
282     #define PUSHLOOP(cx, dat, s) \
283     cx->blk_loop.label = PL_curcop->cop_label; \
284     cx->blk_loop.resetsp = s - PL_stack_base; \
285     cx->blk_loop.redo_op = cLOOP->op_redoop; \
286     cx->blk_loop.next_op = cLOOP->op_nextop; \
287     cx->blk_loop.last_op = cLOOP->op_lastop; \
288     cx->blk_loop.iterlval = Nullsv; \
289     cx->blk_loop.iterary = Nullav; \
290     cx->blk_loop.iterix = -1; \
291     CX_ITERDATA_SET(cx,dat);
292    
293     #define POPLOOP(cx) \
294     SvREFCNT_dec(cx->blk_loop.iterlval); \
295     if (CxITERVAR(cx)) { \
296     SV **s_v_p = CxITERVAR(cx); \
297     sv_2mortal(*s_v_p); \
298     *s_v_p = cx->blk_loop.itersave; \
299     } \
300     if (cx->blk_loop.iterary && cx->blk_loop.iterary != PL_curstack)\
301     SvREFCNT_dec(cx->blk_loop.iterary);
302    
303     /* context common to subroutines, evals and loops */
304     struct block {
305     I32 blku_oldsp; /* stack pointer to copy stuff down to */
306     COP * blku_oldcop; /* old curcop pointer */
307     I32 blku_oldretsp; /* return stack index */
308     I32 blku_oldmarksp; /* mark stack index */
309     I32 blku_oldscopesp; /* scope stack index */
310     PMOP * blku_oldpm; /* values of pattern match vars */
311     U8 blku_gimme; /* is this block running in list context? */
312    
313     union {
314     struct block_sub blku_sub;
315     struct block_eval blku_eval;
316     struct block_loop blku_loop;
317     } blk_u;
318     };
319     #define blk_oldsp cx_u.cx_blk.blku_oldsp
320     #define blk_oldcop cx_u.cx_blk.blku_oldcop
321     #define blk_oldretsp cx_u.cx_blk.blku_oldretsp
322     #define blk_oldmarksp cx_u.cx_blk.blku_oldmarksp
323     #define blk_oldscopesp cx_u.cx_blk.blku_oldscopesp
324     #define blk_oldpm cx_u.cx_blk.blku_oldpm
325     #define blk_gimme cx_u.cx_blk.blku_gimme
326     #define blk_sub cx_u.cx_blk.blk_u.blku_sub
327     #define blk_eval cx_u.cx_blk.blk_u.blku_eval
328     #define blk_loop cx_u.cx_blk.blk_u.blku_loop
329    
330     /* Enter a block. */
331     #define PUSHBLOCK(cx,t,sp) CXINC, cx = &cxstack[cxstack_ix], \
332     cx->cx_type = t, \
333     cx->blk_oldsp = sp - PL_stack_base, \
334     cx->blk_oldcop = PL_curcop, \
335     cx->blk_oldmarksp = PL_markstack_ptr - PL_markstack, \
336     cx->blk_oldscopesp = PL_scopestack_ix, \
337     cx->blk_oldretsp = PL_retstack_ix, \
338     cx->blk_oldpm = PL_curpm, \
339     cx->blk_gimme = (U8)gimme; \
340     DEBUG_l( PerlIO_printf(Perl_debug_log, "Entering block %ld, type %s\n", \
341     (long)cxstack_ix, PL_block_type[CxTYPE(cx)]); )
342    
343     /* Exit a block (RETURN and LAST). */
344     #define POPBLOCK(cx,pm) cx = &cxstack[cxstack_ix--], \
345     newsp = PL_stack_base + cx->blk_oldsp, \
346     PL_curcop = cx->blk_oldcop, \
347     PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp, \
348     PL_scopestack_ix = cx->blk_oldscopesp, \
349     PL_retstack_ix = cx->blk_oldretsp, \
350     pm = cx->blk_oldpm, \
351     gimme = cx->blk_gimme; \
352     DEBUG_SCOPE("POPBLOCK"); \
353     DEBUG_l( PerlIO_printf(Perl_debug_log, "Leaving block %ld, type %s\n", \
354     (long)cxstack_ix+1,PL_block_type[CxTYPE(cx)]); )
355    
356     /* Continue a block elsewhere (NEXT and REDO). */
357     #define TOPBLOCK(cx) cx = &cxstack[cxstack_ix], \
358     PL_stack_sp = PL_stack_base + cx->blk_oldsp, \
359     PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp, \
360     PL_scopestack_ix = cx->blk_oldscopesp, \
361     PL_retstack_ix = cx->blk_oldretsp, \
362     PL_curpm = cx->blk_oldpm; \
363     DEBUG_SCOPE("TOPBLOCK");
364    
365     /* substitution context */
366     struct subst {
367     I32 sbu_iters;
368     I32 sbu_maxiters;
369     I32 sbu_rflags;
370     I32 sbu_oldsave;
371     bool sbu_once;
372     bool sbu_rxtainted;
373     char * sbu_orig;
374     SV * sbu_dstr;
375     SV * sbu_targ;
376     char * sbu_s;
377     char * sbu_m;
378     char * sbu_strend;
379     void * sbu_rxres;
380     REGEXP * sbu_rx;
381     };
382     #define sb_iters cx_u.cx_subst.sbu_iters
383     #define sb_maxiters cx_u.cx_subst.sbu_maxiters
384     #define sb_rflags cx_u.cx_subst.sbu_rflags
385     #define sb_oldsave cx_u.cx_subst.sbu_oldsave
386     #define sb_once cx_u.cx_subst.sbu_once
387     #define sb_rxtainted cx_u.cx_subst.sbu_rxtainted
388     #define sb_orig cx_u.cx_subst.sbu_orig
389     #define sb_dstr cx_u.cx_subst.sbu_dstr
390     #define sb_targ cx_u.cx_subst.sbu_targ
391     #define sb_s cx_u.cx_subst.sbu_s
392     #define sb_m cx_u.cx_subst.sbu_m
393     #define sb_strend cx_u.cx_subst.sbu_strend
394     #define sb_rxres cx_u.cx_subst.sbu_rxres
395     #define sb_rx cx_u.cx_subst.sbu_rx
396    
397     #define PUSHSUBST(cx) CXINC, cx = &cxstack[cxstack_ix], \
398     cx->sb_iters = iters, \
399     cx->sb_maxiters = maxiters, \
400     cx->sb_rflags = r_flags, \
401     cx->sb_oldsave = oldsave, \
402     cx->sb_once = once, \
403     cx->sb_rxtainted = rxtainted, \
404     cx->sb_orig = orig, \
405     cx->sb_dstr = dstr, \
406     cx->sb_targ = targ, \
407     cx->sb_s = s, \
408     cx->sb_m = m, \
409     cx->sb_strend = strend, \
410     cx->sb_rxres = Null(void*), \
411     cx->sb_rx = rx, \
412     cx->cx_type = CXt_SUBST; \
413     rxres_save(&cx->sb_rxres, rx)
414    
415     #define POPSUBST(cx) cx = &cxstack[cxstack_ix--]; \
416     rxres_free(&cx->sb_rxres)
417    
418     struct context {
419     U32 cx_type; /* what kind of context this is */
420     union {
421     struct block cx_blk;
422     struct subst cx_subst;
423     } cx_u;
424     };
425    
426     #define CXTYPEMASK 0xff
427     #define CXt_NULL 0
428     #define CXt_SUB 1
429     #define CXt_EVAL 2
430     #define CXt_LOOP 3
431     #define CXt_SUBST 4
432     #define CXt_BLOCK 5
433     #define CXt_FORMAT 6
434    
435     /* private flags for CXt_EVAL */
436     #define CXp_REAL 0x00000100 /* truly eval'', not a lookalike */
437     #define CXp_TRYBLOCK 0x00000200 /* eval{}, not eval'' or similar */
438    
439     #ifdef USE_ITHREADS
440     /* private flags for CXt_LOOP */
441     # define CXp_PADVAR 0x00000100 /* itervar lives on pad, iterdata
442     has pad offset; if not set,
443     iterdata holds GV* */
444     # define CxPADLOOP(c) (((c)->cx_type & (CXt_LOOP|CXp_PADVAR)) \
445     == (CXt_LOOP|CXp_PADVAR))
446     #endif
447    
448     #define CxTYPE(c) ((c)->cx_type & CXTYPEMASK)
449     #define CxREALEVAL(c) (((c)->cx_type & (CXt_EVAL|CXp_REAL)) \
450     == (CXt_EVAL|CXp_REAL))
451     #define CxTRYBLOCK(c) (((c)->cx_type & (CXt_EVAL|CXp_TRYBLOCK)) \
452     == (CXt_EVAL|CXp_TRYBLOCK))
453    
454     #define CXINC (cxstack_ix < cxstack_max ? ++cxstack_ix : (cxstack_ix = cxinc()))
455    
456     /*
457     =head1 "Gimme" Values
458     */
459    
460     /*
461     =for apidoc AmU||G_SCALAR
462     Used to indicate scalar context. See C<GIMME_V>, C<GIMME>, and
463     L<perlcall>.
464    
465     =for apidoc AmU||G_ARRAY
466     Used to indicate list context. See C<GIMME_V>, C<GIMME> and
467     L<perlcall>.
468    
469     =for apidoc AmU||G_VOID
470     Used to indicate void context. See C<GIMME_V> and L<perlcall>.
471    
472     =for apidoc AmU||G_DISCARD
473     Indicates that arguments returned from a callback should be discarded. See
474     L<perlcall>.
475    
476     =for apidoc AmU||G_EVAL
477    
478     Used to force a Perl C<eval> wrapper around a callback. See
479     L<perlcall>.
480    
481     =for apidoc AmU||G_NOARGS
482    
483     Indicates that no arguments are being sent to a callback. See
484     L<perlcall>.
485    
486     =cut
487     */
488    
489     #define G_SCALAR 0
490     #define G_ARRAY 1
491     #define G_VOID 128 /* skip this bit when adding flags below */
492    
493     /* extra flags for Perl_call_* routines */
494     #define G_DISCARD 2 /* Call FREETMPS. */
495     #define G_EVAL 4 /* Assume eval {} around subroutine call. */
496     #define G_NOARGS 8 /* Don't construct a @_ array. */
497     #define G_KEEPERR 16 /* Append errors to $@, don't overwrite it */
498     #define G_NODEBUG 32 /* Disable debugging at toplevel. */
499     #define G_METHOD 64 /* Calling method. */
500    
501     /* flag bits for PL_in_eval */
502     #define EVAL_NULL 0 /* not in an eval */
503     #define EVAL_INEVAL 1 /* some enclosing scope is an eval */
504     #define EVAL_WARNONLY 2 /* used by yywarn() when calling yyerror() */
505     #define EVAL_KEEPERR 4 /* set by Perl_call_sv if G_KEEPERR */
506     #define EVAL_INREQUIRE 8 /* The code is being required. */
507    
508     /* Support for switching (stack and block) contexts.
509     * This ensures magic doesn't invalidate local stack and cx pointers.
510     */
511    
512     #define PERLSI_UNKNOWN -1
513     #define PERLSI_UNDEF 0
514     #define PERLSI_MAIN 1
515     #define PERLSI_MAGIC 2
516     #define PERLSI_SORT 3
517     #define PERLSI_SIGNAL 4
518     #define PERLSI_OVERLOAD 5
519     #define PERLSI_DESTROY 6
520     #define PERLSI_WARNHOOK 7
521     #define PERLSI_DIEHOOK 8
522     #define PERLSI_REQUIRE 9
523    
524     struct stackinfo {
525     AV * si_stack; /* stack for current runlevel */
526     PERL_CONTEXT * si_cxstack; /* context stack for runlevel */
527     I32 si_cxix; /* current context index */
528     I32 si_cxmax; /* maximum allocated index */
529     I32 si_type; /* type of runlevel */
530     struct stackinfo * si_prev;
531     struct stackinfo * si_next;
532     I32 si_markoff; /* offset where markstack begins for us.
533     * currently used only with DEBUGGING,
534     * but not #ifdef-ed for bincompat */
535     };
536    
537     typedef struct stackinfo PERL_SI;
538    
539     #define cxstack (PL_curstackinfo->si_cxstack)
540     #define cxstack_ix (PL_curstackinfo->si_cxix)
541     #define cxstack_max (PL_curstackinfo->si_cxmax)
542    
543     #ifdef DEBUGGING
544     # define SET_MARK_OFFSET \
545     PL_curstackinfo->si_markoff = PL_markstack_ptr - PL_markstack
546     #else
547     # define SET_MARK_OFFSET NOOP
548     #endif
549    
550     #define PUSHSTACKi(type) \
551     STMT_START { \
552     PERL_SI *next = PL_curstackinfo->si_next; \
553     if (!next) { \
554     next = new_stackinfo(32, 2048/sizeof(PERL_CONTEXT) - 1); \
555     next->si_prev = PL_curstackinfo; \
556     PL_curstackinfo->si_next = next; \
557     } \
558     next->si_type = type; \
559     next->si_cxix = -1; \
560     AvFILLp(next->si_stack) = 0; \
561     SWITCHSTACK(PL_curstack,next->si_stack); \
562     PL_curstackinfo = next; \
563     SET_MARK_OFFSET; \
564     } STMT_END
565    
566     #define PUSHSTACK PUSHSTACKi(PERLSI_UNKNOWN)
567    
568     /* POPSTACK works with PL_stack_sp, so it may need to be bracketed by
569     * PUTBACK/SPAGAIN to flush/refresh any local SP that may be active */
570     #define POPSTACK \
571     STMT_START { \
572     dSP; \
573     PERL_SI *prev = PL_curstackinfo->si_prev; \
574     if (!prev) { \
575     PerlIO_printf(Perl_error_log, "panic: POPSTACK\n"); \
576     my_exit(1); \
577     } \
578     SWITCHSTACK(PL_curstack,prev->si_stack); \
579     /* don't free prev here, free them all at the END{} */ \
580     PL_curstackinfo = prev; \
581     } STMT_END
582    
583     #define POPSTACK_TO(s) \
584     STMT_START { \
585     while (PL_curstack != s) { \
586     dounwind(-1); \
587     POPSTACK; \
588     } \
589     } STMT_END
590    
591     #define IN_PERL_COMPILETIME (PL_curcop == &PL_compiling)
592     #define IN_PERL_RUNTIME (PL_curcop != &PL_compiling)
593