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move the SETJMP exception-handing definitions from scope.h to cop.h
[perl5.git] / cop.h
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 /* A jmpenv packages the state required to perform a proper non-local jump.
17  * Note that there is a start_env initialized when perl starts, and top_env
18  * points to this initially, so top_env should always be non-null.
19  *
20  * Existence of a non-null top_env->je_prev implies it is valid to call
21  * longjmp() at that runlevel (we make sure start_env.je_prev is always
22  * null to ensure this).
23  *
24  * je_mustcatch, when set at any runlevel to TRUE, means eval ops must
25  * establish a local jmpenv to handle exception traps.  Care must be taken
26  * to restore the previous value of je_mustcatch before exiting the
27  * stack frame iff JMPENV_PUSH was not called in that stack frame.
28  * GSAR 97-03-27
29  */
30
31 struct jmpenv {
32     struct jmpenv *     je_prev;
33     Sigjmp_buf          je_buf;         /* only for use if !je_throw */
34     int                 je_ret;         /* last exception thrown */
35     bool                je_mustcatch;   /* need to call longjmp()? */
36 };
37
38 typedef struct jmpenv JMPENV;
39
40 #ifdef OP_IN_REGISTER
41 #define OP_REG_TO_MEM   PL_opsave = op
42 #define OP_MEM_TO_REG   op = PL_opsave
43 #else
44 #define OP_REG_TO_MEM   NOOP
45 #define OP_MEM_TO_REG   NOOP
46 #endif
47
48 /*
49  * How to build the first jmpenv.
50  *
51  * top_env needs to be non-zero. It points to an area
52  * in which longjmp() stuff is stored, as C callstack
53  * info there at least is thread specific this has to
54  * be per-thread. Otherwise a 'die' in a thread gives
55  * that thread the C stack of last thread to do an eval {}!
56  */
57
58 #define JMPENV_BOOTSTRAP \
59     STMT_START {                                \
60         Zero(&PL_start_env, 1, JMPENV);         \
61         PL_start_env.je_ret = -1;               \
62         PL_start_env.je_mustcatch = TRUE;       \
63         PL_top_env = &PL_start_env;             \
64     } STMT_END
65
66 /*
67  *   PERL_FLEXIBLE_EXCEPTIONS
68  * 
69  * All the flexible exceptions code has been removed.
70  * See the following threads for details:
71  *
72  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/2004-07/msg00378.html
73  * 
74  * Joshua's original patches (which weren't applied) and discussion:
75  * 
76  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01396.html
77  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01489.html
78  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01491.html
79  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01608.html
80  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg02144.html
81  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg02998.html
82  * 
83  * Chip's reworked patch and discussion:
84  * 
85  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1999-03/msg00520.html
86  * 
87  * The flaw in these patches (which went unnoticed at the time) was
88  * that they moved some code that could potentially die() out of the
89  * region protected by the setjmp()s.  This caused exceptions within
90  * END blocks and such to not be handled by the correct setjmp().
91  * 
92  * The original patches that introduces flexible exceptions were:
93  *
94  *   http://public.activestate.com/cgi-bin/perlbrowse?patch=3386
95  *   http://public.activestate.com/cgi-bin/perlbrowse?patch=5162
96  */
97
98 #define dJMPENV         JMPENV cur_env
99
100 #define JMPENV_PUSH(v) \
101     STMT_START {                                                        \
102         DEBUG_l(Perl_deb(aTHX_ "Setting up jumplevel %p, was %p\n",     \
103                          &cur_env, PL_top_env));                        \
104         cur_env.je_prev = PL_top_env;                                   \
105         OP_REG_TO_MEM;                                                  \
106         cur_env.je_ret = PerlProc_setjmp(cur_env.je_buf, SCOPE_SAVES_SIGNAL_MASK);              \
107         OP_MEM_TO_REG;                                                  \
108         PL_top_env = &cur_env;                                          \
109         cur_env.je_mustcatch = FALSE;                                   \
110         (v) = cur_env.je_ret;                                           \
111     } STMT_END
112
113 #define JMPENV_POP \
114     STMT_START {                                                        \
115         DEBUG_l(Perl_deb(aTHX_ "popping jumplevel was %p, now %p\n",    \
116                          PL_top_env, cur_env.je_prev));                 \
117         PL_top_env = cur_env.je_prev;                                   \
118     } STMT_END
119
120 #define JMPENV_JUMP(v) \
121     STMT_START {                                                \
122         OP_REG_TO_MEM;                                          \
123         if (PL_top_env->je_prev)                                \
124             PerlProc_longjmp(PL_top_env->je_buf, (v));          \
125         if ((v) == 2)                                           \
126             PerlProc_exit(STATUS_NATIVE_EXPORT);                \
127         PerlIO_printf(PerlIO_stderr(), "panic: top_env\n");     \
128         PerlProc_exit(1);                                       \
129     } STMT_END
130
131 #define CATCH_GET               (PL_top_env->je_mustcatch)
132 #define CATCH_SET(v)            (PL_top_env->je_mustcatch = (v))
133
134
135
136 struct cop {
137     BASEOP
138     char *      cop_label;      /* label for this construct */
139 #ifdef USE_ITHREADS
140     char *      cop_stashpv;    /* package line was compiled in */
141     char *      cop_file;       /* file name the following line # is from */
142 #else
143     HV *        cop_stash;      /* package line was compiled in */
144     GV *        cop_filegv;     /* file the following line # is from */
145 #endif
146     U32         cop_seq;        /* parse sequence number */
147     I32         cop_arybase;    /* array base this line was compiled with */
148     line_t      cop_line;       /* line # of this command */
149     SV *        cop_warnings;   /* lexical warnings bitmask */
150     SV *        cop_io;         /* lexical IO defaults */
151 };
152
153 #define Nullcop Null(COP*)
154
155 #ifdef USE_ITHREADS
156 #  define CopFILE(c)            ((c)->cop_file)
157 #  define CopFILEGV(c)          (CopFILE(c) \
158                                  ? gv_fetchfile(CopFILE(c)) : Nullgv)
159                                  
160 #  ifdef NETWARE
161 #    define CopFILE_set(c,pv)   ((c)->cop_file = savepv(pv))
162 #  else
163 #    define CopFILE_set(c,pv)   ((c)->cop_file = savesharedpv(pv))
164 #  endif
165
166 #  define CopFILESV(c)          (CopFILE(c) \
167                                  ? GvSV(gv_fetchfile(CopFILE(c))) : Nullsv)
168 #  define CopFILEAV(c)          (CopFILE(c) \
169                                  ? GvAV(gv_fetchfile(CopFILE(c))) : Nullav)
170 #  define CopSTASHPV(c)         ((c)->cop_stashpv)
171
172 #  ifdef NETWARE
173 #    define CopSTASHPV_set(c,pv)        ((c)->cop_stashpv = ((pv) ? savepv(pv) : Nullch))
174 #  else
175 #    define CopSTASHPV_set(c,pv)        ((c)->cop_stashpv = savesharedpv(pv))
176 #  endif
177
178 #  define CopSTASH(c)           (CopSTASHPV(c) \
179                                  ? gv_stashpv(CopSTASHPV(c),GV_ADD) : Nullhv)
180 #  define CopSTASH_set(c,hv)    CopSTASHPV_set(c, (hv) ? HvNAME(hv) : Nullch)
181 #  define CopSTASH_eq(c,hv)     ((hv)                                   \
182                                  && (CopSTASHPV(c) == HvNAME(hv)        \
183                                      || (CopSTASHPV(c) && HvNAME(hv)    \
184                                          && strEQ(CopSTASHPV(c), HvNAME(hv)))))
185 #  ifdef NETWARE
186 #    define CopSTASH_free(c) SAVECOPSTASH_FREE(c)
187 #  else
188 #    define CopSTASH_free(c)    PerlMemShared_free(CopSTASHPV(c))      
189 #  endif
190
191 #  ifdef NETWARE
192 #    define CopFILE_free(c) SAVECOPFILE_FREE(c)
193 #  else
194 #    define CopFILE_free(c)     (PerlMemShared_free(CopFILE(c)),(CopFILE(c) = Nullch))      
195 #  endif
196 #else
197 #  define CopFILEGV(c)          ((c)->cop_filegv)
198 #  define CopFILEGV_set(c,gv)   ((c)->cop_filegv = (GV*)SvREFCNT_inc(gv))
199 #  define CopFILE_set(c,pv)     CopFILEGV_set((c), gv_fetchfile(pv))
200 #  define CopFILESV(c)          (CopFILEGV(c) ? GvSV(CopFILEGV(c)) : Nullsv)
201 #  define CopFILEAV(c)          (CopFILEGV(c) ? GvAV(CopFILEGV(c)) : Nullav)
202 #  define CopFILE(c)            (CopFILESV(c) ? SvPVX(CopFILESV(c)) : Nullch)
203 #  define CopSTASH(c)           ((c)->cop_stash)
204 #  define CopSTASH_set(c,hv)    ((c)->cop_stash = (hv))
205 #  define CopSTASHPV(c)         (CopSTASH(c) ? HvNAME(CopSTASH(c)) : Nullch)
206    /* cop_stash is not refcounted */
207 #  define CopSTASHPV_set(c,pv)  CopSTASH_set((c), gv_stashpv(pv,GV_ADD))
208 #  define CopSTASH_eq(c,hv)     (CopSTASH(c) == (hv))
209 #  define CopSTASH_free(c)      
210 #  define CopFILE_free(c)       (SvREFCNT_dec(CopFILEGV(c)),(CopFILEGV(c) = Nullgv))
211
212 #endif /* USE_ITHREADS */
213
214 #define CopSTASH_ne(c,hv)       (!CopSTASH_eq(c,hv))
215 #define CopLINE(c)              ((c)->cop_line)
216 #define CopLINE_inc(c)          (++CopLINE(c))
217 #define CopLINE_dec(c)          (--CopLINE(c))
218 #define CopLINE_set(c,l)        (CopLINE(c) = (l))
219
220 /* OutCopFILE() is CopFILE for output (caller, die, warn, etc.) */
221 #ifdef MACOS_TRADITIONAL
222 #  define OutCopFILE(c) MacPerl_MPWFileName(CopFILE(c))
223 #else
224 #  define OutCopFILE(c) CopFILE(c)
225 #endif
226
227 /*
228  * Here we have some enormously heavy (or at least ponderous) wizardry.
229  */
230
231 /* subroutine context */
232 struct block_sub {
233     CV *        cv;
234     GV *        gv;
235     GV *        dfoutgv;
236     AV *        savearray;
237     AV *        argarray;
238     long        olddepth;
239     U8          hasargs;
240     U8          lval;           /* XXX merge lval and hasargs? */
241     PAD         *oldcomppad;
242     OP *        retop;  /* op to execute on exit from sub */
243 };
244
245 /* base for the next two macros. Don't use directly.
246  * Note that the refcnt of the cv is incremented twice;  The CX one is
247  * decremented by LEAVESUB, the other by LEAVE. */
248
249 #define PUSHSUB_BASE(cx)                                                \
250         cx->blk_sub.cv = cv;                                            \
251         cx->blk_sub.olddepth = CvDEPTH(cv);                             \
252         cx->blk_sub.hasargs = hasargs;                                  \
253         cx->blk_sub.retop = Nullop;                                             \
254         if (!CvDEPTH(cv)) {                                             \
255             (void)SvREFCNT_inc(cv);                                     \
256             (void)SvREFCNT_inc(cv);                                     \
257             SAVEFREESV(cv);                                             \
258         }
259
260
261 #define PUSHSUB(cx)                                                     \
262         PUSHSUB_BASE(cx)                                                \
263         cx->blk_sub.lval = PL_op->op_private &                          \
264                               (OPpLVAL_INTRO|OPpENTERSUB_INARGS);
265
266 /* variant for use by OP_DBSTATE, where op_private holds hint bits */
267 #define PUSHSUB_DB(cx)                                                  \
268         PUSHSUB_BASE(cx)                                                \
269         cx->blk_sub.lval = 0;
270
271
272 #define PUSHFORMAT(cx)                                                  \
273         cx->blk_sub.cv = cv;                                            \
274         cx->blk_sub.gv = gv;                                            \
275         cx->blk_sub.retop = Nullop;                                     \
276         cx->blk_sub.hasargs = 0;                                        \
277         cx->blk_sub.dfoutgv = PL_defoutgv;                              \
278         (void)SvREFCNT_inc(cx->blk_sub.dfoutgv)
279
280 #define POP_SAVEARRAY()                                         \
281     STMT_START {                                                        \
282         SvREFCNT_dec(GvAV(PL_defgv));                                   \
283         GvAV(PL_defgv) = cx->blk_sub.savearray;                         \
284     } STMT_END
285
286 /* junk in @_ spells trouble when cloning CVs and in pp_caller(), so don't
287  * leave any (a fast av_clear(ary), basically) */
288 #define CLEAR_ARGARRAY(ary) \
289     STMT_START {                                                        \
290         AvMAX(ary) += AvARRAY(ary) - AvALLOC(ary);                      \
291         SvPV_set(ary, (char*)AvALLOC(ary));                             \
292         AvFILLp(ary) = -1;                                              \
293     } STMT_END
294
295 #define POPSUB(cx,sv)                                                   \
296     STMT_START {                                                        \
297         if (cx->blk_sub.hasargs) {                                      \
298             POP_SAVEARRAY();                                            \
299             /* abandon @_ if it got reified */                          \
300             if (AvREAL(cx->blk_sub.argarray)) {                         \
301                 SSize_t fill = AvFILLp(cx->blk_sub.argarray);           \
302                 SvREFCNT_dec(cx->blk_sub.argarray);                     \
303                 cx->blk_sub.argarray = newAV();                         \
304                 av_extend(cx->blk_sub.argarray, fill);                  \
305                 AvFLAGS(cx->blk_sub.argarray) = AVf_REIFY;              \
306                 CX_CURPAD_SV(cx->blk_sub, 0) = (SV*)cx->blk_sub.argarray;       \
307             }                                                           \
308             else {                                                      \
309                 CLEAR_ARGARRAY(cx->blk_sub.argarray);                   \
310             }                                                           \
311         }                                                               \
312         sv = (SV*)cx->blk_sub.cv;                                       \
313         if (sv && (CvDEPTH((CV*)sv) = cx->blk_sub.olddepth))            \
314             sv = Nullsv;                                                \
315     } STMT_END
316
317 #define LEAVESUB(sv)                                                    \
318     STMT_START {                                                        \
319         if (sv)                                                         \
320             SvREFCNT_dec(sv);                                           \
321     } STMT_END
322
323 #define POPFORMAT(cx)                                                   \
324         setdefout(cx->blk_sub.dfoutgv);                                 \
325         SvREFCNT_dec(cx->blk_sub.dfoutgv);
326
327 /* eval context */
328 struct block_eval {
329     I32         old_in_eval;
330     I32         old_op_type;
331     SV *        old_namesv;
332     OP *        old_eval_root;
333     SV *        cur_text;
334     CV *        cv;
335     OP *        retop;  /* op to execute on exit from eval */
336 };
337
338 #define PUSHEVAL(cx,n,fgv)                                              \
339     STMT_START {                                                        \
340         cx->blk_eval.old_in_eval = PL_in_eval;                          \
341         cx->blk_eval.old_op_type = PL_op->op_type;                      \
342         cx->blk_eval.old_namesv = (n ? newSVpv(n,0) : Nullsv);          \
343         cx->blk_eval.old_eval_root = PL_eval_root;                      \
344         cx->blk_eval.cur_text = PL_linestr;                             \
345         cx->blk_eval.cv = Nullcv; /* set by doeval(), as applicable */  \
346         cx->blk_eval.retop = Nullop;                                    \
347     } STMT_END
348
349 #define POPEVAL(cx)                                                     \
350     STMT_START {                                                        \
351         PL_in_eval = cx->blk_eval.old_in_eval;                          \
352         optype = cx->blk_eval.old_op_type;                              \
353         PL_eval_root = cx->blk_eval.old_eval_root;                      \
354         if (cx->blk_eval.old_namesv)                                    \
355             sv_2mortal(cx->blk_eval.old_namesv);                        \
356     } STMT_END
357
358 /* loop context */
359 struct block_loop {
360     char *      label;
361     I32         resetsp;
362     OP *        redo_op;
363     OP *        next_op;
364     OP *        last_op;
365 #ifdef USE_ITHREADS
366     void *      iterdata;
367     PAD         *oldcomppad;
368 #else
369     SV **       itervar;
370 #endif
371     SV *        itersave;
372     SV *        iterlval;
373     AV *        iterary;
374     IV          iterix;
375     IV          itermax;
376 };
377
378 #ifdef USE_ITHREADS
379 #  define CxITERVAR(c)                                                  \
380         ((c)->blk_loop.iterdata                                         \
381          ? (CxPADLOOP(cx)                                               \
382             ? &CX_CURPAD_SV( (c)->blk_loop,                             \
383                     INT2PTR(PADOFFSET, (c)->blk_loop.iterdata))         \
384             : &GvSV((GV*)(c)->blk_loop.iterdata))                       \
385          : (SV**)NULL)
386 #  define CX_ITERDATA_SET(cx,idata)                                     \
387         CX_CURPAD_SAVE(cx->blk_loop);                                   \
388         if ((cx->blk_loop.iterdata = (idata)))                          \
389             cx->blk_loop.itersave = SvREFCNT_inc(*CxITERVAR(cx));       \
390         else                                                            \
391             cx->blk_loop.itersave = Nullsv;
392 #else
393 #  define CxITERVAR(c)          ((c)->blk_loop.itervar)
394 #  define CX_ITERDATA_SET(cx,ivar)                                      \
395         if ((cx->blk_loop.itervar = (SV**)(ivar)))                      \
396             cx->blk_loop.itersave = SvREFCNT_inc(*CxITERVAR(cx));       \
397         else                                                            \
398             cx->blk_loop.itersave = Nullsv;
399 #endif
400
401 #define PUSHLOOP(cx, dat, s)                                            \
402         cx->blk_loop.label = PL_curcop->cop_label;                      \
403         cx->blk_loop.resetsp = s - PL_stack_base;                       \
404         cx->blk_loop.redo_op = cLOOP->op_redoop;                        \
405         cx->blk_loop.next_op = cLOOP->op_nextop;                        \
406         cx->blk_loop.last_op = cLOOP->op_lastop;                        \
407         cx->blk_loop.iterlval = Nullsv;                                 \
408         cx->blk_loop.iterary = Nullav;                                  \
409         cx->blk_loop.iterix = -1;                                       \
410         CX_ITERDATA_SET(cx,dat);
411
412 #define POPLOOP(cx)                                                     \
413         SvREFCNT_dec(cx->blk_loop.iterlval);                            \
414         if (CxITERVAR(cx)) {                                            \
415             SV **s_v_p = CxITERVAR(cx);                                 \
416             sv_2mortal(*s_v_p);                                         \
417             *s_v_p = cx->blk_loop.itersave;                             \
418         }                                                               \
419         if (cx->blk_loop.iterary && cx->blk_loop.iterary != PL_curstack)\
420             SvREFCNT_dec(cx->blk_loop.iterary);
421
422 /* context common to subroutines, evals and loops */
423 struct block {
424     I32         blku_oldsp;     /* stack pointer to copy stuff down to */
425     COP *       blku_oldcop;    /* old curcop pointer */
426     I32         blku_oldmarksp; /* mark stack index */
427     I32         blku_oldscopesp;        /* scope stack index */
428     PMOP *      blku_oldpm;     /* values of pattern match vars */
429     U8          blku_gimme;     /* is this block running in list context? */
430
431     union {
432         struct block_sub        blku_sub;
433         struct block_eval       blku_eval;
434         struct block_loop       blku_loop;
435     } blk_u;
436 };
437 #define blk_oldsp       cx_u.cx_blk.blku_oldsp
438 #define blk_oldcop      cx_u.cx_blk.blku_oldcop
439 #define blk_oldmarksp   cx_u.cx_blk.blku_oldmarksp
440 #define blk_oldscopesp  cx_u.cx_blk.blku_oldscopesp
441 #define blk_oldpm       cx_u.cx_blk.blku_oldpm
442 #define blk_gimme       cx_u.cx_blk.blku_gimme
443 #define blk_sub         cx_u.cx_blk.blk_u.blku_sub
444 #define blk_eval        cx_u.cx_blk.blk_u.blku_eval
445 #define blk_loop        cx_u.cx_blk.blk_u.blku_loop
446
447 /* Enter a block. */
448 #define PUSHBLOCK(cx,t,sp) CXINC, cx = &cxstack[cxstack_ix],            \
449         cx->cx_type             = t,                                    \
450         cx->blk_oldsp           = sp - PL_stack_base,                   \
451         cx->blk_oldcop          = PL_curcop,                            \
452         cx->blk_oldmarksp       = PL_markstack_ptr - PL_markstack,      \
453         cx->blk_oldscopesp      = PL_scopestack_ix,                     \
454         cx->blk_oldpm           = PL_curpm,                             \
455         cx->blk_gimme           = (U8)gimme;                            \
456         DEBUG_l( PerlIO_printf(Perl_debug_log, "Entering block %ld, type %s\n", \
457                     (long)cxstack_ix, PL_block_type[CxTYPE(cx)]); )
458
459 /* Exit a block (RETURN and LAST). */
460 #define POPBLOCK(cx,pm) cx = &cxstack[cxstack_ix--],                    \
461         newsp            = PL_stack_base + cx->blk_oldsp,               \
462         PL_curcop        = cx->blk_oldcop,                              \
463         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
464         PL_scopestack_ix = cx->blk_oldscopesp,                          \
465         pm               = cx->blk_oldpm,                               \
466         gimme            = cx->blk_gimme;                               \
467         DEBUG_SCOPE("POPBLOCK");                                        \
468         DEBUG_l( PerlIO_printf(Perl_debug_log, "Leaving block %ld, type %s\n",          \
469                     (long)cxstack_ix+1,PL_block_type[CxTYPE(cx)]); )
470
471 /* Continue a block elsewhere (NEXT and REDO). */
472 #define TOPBLOCK(cx) cx  = &cxstack[cxstack_ix],                        \
473         PL_stack_sp      = PL_stack_base + cx->blk_oldsp,               \
474         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
475         PL_scopestack_ix = cx->blk_oldscopesp,                          \
476         PL_curpm         = cx->blk_oldpm;                               \
477         DEBUG_SCOPE("TOPBLOCK");
478
479 /* substitution context */
480 struct subst {
481     I32         sbu_iters;
482     I32         sbu_maxiters;
483     I32         sbu_rflags;
484     I32         sbu_oldsave;
485     bool        sbu_once;
486     bool        sbu_rxtainted;
487     char *      sbu_orig;
488     SV *        sbu_dstr;
489     SV *        sbu_targ;
490     char *      sbu_s;
491     char *      sbu_m;
492     char *      sbu_strend;
493     void *      sbu_rxres;
494     REGEXP *    sbu_rx;
495 };
496 #define sb_iters        cx_u.cx_subst.sbu_iters
497 #define sb_maxiters     cx_u.cx_subst.sbu_maxiters
498 #define sb_rflags       cx_u.cx_subst.sbu_rflags
499 #define sb_oldsave      cx_u.cx_subst.sbu_oldsave
500 #define sb_once         cx_u.cx_subst.sbu_once
501 #define sb_rxtainted    cx_u.cx_subst.sbu_rxtainted
502 #define sb_orig         cx_u.cx_subst.sbu_orig
503 #define sb_dstr         cx_u.cx_subst.sbu_dstr
504 #define sb_targ         cx_u.cx_subst.sbu_targ
505 #define sb_s            cx_u.cx_subst.sbu_s
506 #define sb_m            cx_u.cx_subst.sbu_m
507 #define sb_strend       cx_u.cx_subst.sbu_strend
508 #define sb_rxres        cx_u.cx_subst.sbu_rxres
509 #define sb_rx           cx_u.cx_subst.sbu_rx
510
511 #define PUSHSUBST(cx) CXINC, cx = &cxstack[cxstack_ix],                 \
512         cx->sb_iters            = iters,                                \
513         cx->sb_maxiters         = maxiters,                             \
514         cx->sb_rflags           = r_flags,                              \
515         cx->sb_oldsave          = oldsave,                              \
516         cx->sb_once             = once,                                 \
517         cx->sb_rxtainted        = rxtainted,                            \
518         cx->sb_orig             = orig,                                 \
519         cx->sb_dstr             = dstr,                                 \
520         cx->sb_targ             = targ,                                 \
521         cx->sb_s                = s,                                    \
522         cx->sb_m                = m,                                    \
523         cx->sb_strend           = strend,                               \
524         cx->sb_rxres            = Null(void*),                          \
525         cx->sb_rx               = rx,                                   \
526         cx->cx_type             = CXt_SUBST;                            \
527         rxres_save(&cx->sb_rxres, rx)
528
529 #define POPSUBST(cx) cx = &cxstack[cxstack_ix--];                       \
530         rxres_free(&cx->sb_rxres)
531
532 struct context {
533     U32         cx_type;        /* what kind of context this is */
534     union {
535         struct block    cx_blk;
536         struct subst    cx_subst;
537     } cx_u;
538 };
539
540 #define CXTYPEMASK      0xff
541 #define CXt_NULL        0
542 #define CXt_SUB         1
543 #define CXt_EVAL        2
544 #define CXt_LOOP        3
545 #define CXt_SUBST       4
546 #define CXt_BLOCK       5
547 #define CXt_FORMAT      6
548
549 /* private flags for CXt_EVAL */
550 #define CXp_REAL        0x00000100      /* truly eval'', not a lookalike */
551 #define CXp_TRYBLOCK    0x00000200      /* eval{}, not eval'' or similar */
552
553 #ifdef USE_ITHREADS
554 /* private flags for CXt_LOOP */
555 #  define CXp_PADVAR    0x00000100      /* itervar lives on pad, iterdata
556                                            has pad offset; if not set,
557                                            iterdata holds GV* */
558 #  define CxPADLOOP(c)  (((c)->cx_type & (CXt_LOOP|CXp_PADVAR))         \
559                          == (CXt_LOOP|CXp_PADVAR))
560 #endif
561
562 #define CxTYPE(c)       ((c)->cx_type & CXTYPEMASK)
563 #define CxREALEVAL(c)   (((c)->cx_type & (CXt_EVAL|CXp_REAL))           \
564                          == (CXt_EVAL|CXp_REAL))
565 #define CxTRYBLOCK(c)   (((c)->cx_type & (CXt_EVAL|CXp_TRYBLOCK))       \
566                          == (CXt_EVAL|CXp_TRYBLOCK))
567
568 #define CXINC (cxstack_ix < cxstack_max ? ++cxstack_ix : (cxstack_ix = cxinc()))
569
570 /* 
571 =head1 "Gimme" Values
572 */
573
574 /*
575 =for apidoc AmU||G_SCALAR
576 Used to indicate scalar context.  See C<GIMME_V>, C<GIMME>, and
577 L<perlcall>.
578
579 =for apidoc AmU||G_ARRAY
580 Used to indicate list context.  See C<GIMME_V>, C<GIMME> and
581 L<perlcall>.
582
583 =for apidoc AmU||G_VOID
584 Used to indicate void context.  See C<GIMME_V> and L<perlcall>.
585
586 =for apidoc AmU||G_DISCARD
587 Indicates that arguments returned from a callback should be discarded.  See
588 L<perlcall>.
589
590 =for apidoc AmU||G_EVAL
591
592 Used to force a Perl C<eval> wrapper around a callback.  See
593 L<perlcall>.
594
595 =for apidoc AmU||G_NOARGS
596
597 Indicates that no arguments are being sent to a callback.  See
598 L<perlcall>.
599
600 =cut
601 */
602
603 #define G_SCALAR        0
604 #define G_ARRAY         1
605 #define G_VOID          128     /* skip this bit when adding flags below */
606
607 /* extra flags for Perl_call_* routines */
608 #define G_DISCARD       2       /* Call FREETMPS. */
609 #define G_EVAL          4       /* Assume eval {} around subroutine call. */
610 #define G_NOARGS        8       /* Don't construct a @_ array. */
611 #define G_KEEPERR      16       /* Append errors to $@, don't overwrite it */
612 #define G_NODEBUG      32       /* Disable debugging at toplevel.  */
613 #define G_METHOD       64       /* Calling method. */
614
615 /* flag bits for PL_in_eval */
616 #define EVAL_NULL       0       /* not in an eval */
617 #define EVAL_INEVAL     1       /* some enclosing scope is an eval */
618 #define EVAL_WARNONLY   2       /* used by yywarn() when calling yyerror() */
619 #define EVAL_KEEPERR    4       /* set by Perl_call_sv if G_KEEPERR */
620 #define EVAL_INREQUIRE  8       /* The code is being required. */
621
622 /* Support for switching (stack and block) contexts.
623  * This ensures magic doesn't invalidate local stack and cx pointers.
624  */
625
626 #define PERLSI_UNKNOWN          -1
627 #define PERLSI_UNDEF            0
628 #define PERLSI_MAIN             1
629 #define PERLSI_MAGIC            2
630 #define PERLSI_SORT             3
631 #define PERLSI_SIGNAL           4
632 #define PERLSI_OVERLOAD         5
633 #define PERLSI_DESTROY          6
634 #define PERLSI_WARNHOOK         7
635 #define PERLSI_DIEHOOK          8
636 #define PERLSI_REQUIRE          9
637
638 struct stackinfo {
639     AV *                si_stack;       /* stack for current runlevel */
640     PERL_CONTEXT *      si_cxstack;     /* context stack for runlevel */
641     I32                 si_cxix;        /* current context index */
642     I32                 si_cxmax;       /* maximum allocated index */
643     I32                 si_type;        /* type of runlevel */
644     struct stackinfo *  si_prev;
645     struct stackinfo *  si_next;
646     I32                 si_markoff;     /* offset where markstack begins for us.
647                                          * currently used only with DEBUGGING,
648                                          * but not #ifdef-ed for bincompat */
649 };
650
651 typedef struct stackinfo PERL_SI;
652
653 #define cxstack         (PL_curstackinfo->si_cxstack)
654 #define cxstack_ix      (PL_curstackinfo->si_cxix)
655 #define cxstack_max     (PL_curstackinfo->si_cxmax)
656
657 #ifdef DEBUGGING
658 #  define       SET_MARK_OFFSET \
659     PL_curstackinfo->si_markoff = PL_markstack_ptr - PL_markstack
660 #else
661 #  define       SET_MARK_OFFSET NOOP
662 #endif
663
664 #define PUSHSTACKi(type) \
665     STMT_START {                                                        \
666         PERL_SI *next = PL_curstackinfo->si_next;                       \
667         if (!next) {                                                    \
668             next = new_stackinfo(32, 2048/sizeof(PERL_CONTEXT) - 1);    \
669             next->si_prev = PL_curstackinfo;                            \
670             PL_curstackinfo->si_next = next;                            \
671         }                                                               \
672         next->si_type = type;                                           \
673         next->si_cxix = -1;                                             \
674         AvFILLp(next->si_stack) = 0;                                    \
675         SWITCHSTACK(PL_curstack,next->si_stack);                        \
676         PL_curstackinfo = next;                                         \
677         SET_MARK_OFFSET;                                                \
678     } STMT_END
679
680 #define PUSHSTACK PUSHSTACKi(PERLSI_UNKNOWN)
681
682 /* POPSTACK works with PL_stack_sp, so it may need to be bracketed by
683  * PUTBACK/SPAGAIN to flush/refresh any local SP that may be active */
684 #define POPSTACK \
685     STMT_START {                                                        \
686         dSP;                                                            \
687         PERL_SI *prev = PL_curstackinfo->si_prev;                       \
688         if (!prev) {                                                    \
689             PerlIO_printf(Perl_error_log, "panic: POPSTACK\n");         \
690             my_exit(1);                                                 \
691         }                                                               \
692         SWITCHSTACK(PL_curstack,prev->si_stack);                        \
693         /* don't free prev here, free them all at the END{} */          \
694         PL_curstackinfo = prev;                                         \
695     } STMT_END
696
697 #define POPSTACK_TO(s) \
698     STMT_START {                                                        \
699         while (PL_curstack != s) {                                      \
700             dounwind(-1);                                               \
701             POPSTACK;                                                   \
702         }                                                               \
703     } STMT_END
704
705 #define IN_PERL_COMPILETIME     (PL_curcop == &PL_compiling)
706 #define IN_PERL_RUNTIME         (PL_curcop != &PL_compiling)
707