xref: /openbsd-src/gnu/usr.bin/perl/cop.h (revision 99fd087599a8791921855f21bd7e36130f39aadc)
1 /*    cop.h
2  *
3  *    Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
4  *    2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 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 two ops OP_NEXTSTATE and OP_DBSTATE,
10  * that (loosely speaking) are statement separators.
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 PL_start_env initialized when perl starts, and
18  * PL_top_env points to this initially, so PL_top_env should always be
19  * non-null.
20  *
21  * Existence of a non-null PL_top_env->je_prev implies it is valid to call
22  * longjmp() at that runlevel (we make sure PL_start_env.je_prev is always
23  * null to ensure this).
24  *
25  * je_mustcatch, when set at any runlevel to TRUE, means eval ops must
26  * establish a local jmpenv to handle exception traps.  Care must be taken
27  * to restore the previous value of je_mustcatch before exiting the
28  * stack frame iff JMPENV_PUSH was not called in that stack frame.
29  * GSAR 97-03-27
30  */
31 
32 struct jmpenv {
33     struct jmpenv *	je_prev;
34     Sigjmp_buf		je_buf;		/* uninit if je_prev is NULL */
35     int			je_ret;		/* last exception thrown */
36     bool		je_mustcatch;	/* need to call longjmp()? */
37     U16                 je_old_delaymagic; /* saved PL_delaymagic */
38     SSize_t             je_old_stack_hwm;
39 };
40 
41 typedef struct jmpenv JMPENV;
42 
43 #if defined DEBUGGING && !defined DEBUGGING_RE_ONLY
44 #  define JE_OLD_STACK_HWM_zero      PL_start_env.je_old_stack_hwm = 0
45 #  define JE_OLD_STACK_HWM_save(je)  \
46         (je).je_old_stack_hwm = PL_curstackinfo->si_stack_hwm
47 #  define JE_OLD_STACK_HWM_restore(je)  \
48         if (PL_curstackinfo->si_stack_hwm < (je).je_old_stack_hwm) \
49             PL_curstackinfo->si_stack_hwm = (je).je_old_stack_hwm
50 #else
51 #  define JE_OLD_STACK_HWM_zero        NOOP
52 #  define JE_OLD_STACK_HWM_save(je)    NOOP
53 #  define JE_OLD_STACK_HWM_restore(je) NOOP
54 #endif
55 
56 /*
57  * How to build the first jmpenv.
58  *
59  * top_env needs to be non-zero. It points to an area
60  * in which longjmp() stuff is stored, as C callstack
61  * info there at least is thread specific this has to
62  * be per-thread. Otherwise a 'die' in a thread gives
63  * that thread the C stack of last thread to do an eval {}!
64  */
65 
66 #define JMPENV_BOOTSTRAP \
67     STMT_START {				\
68 	PERL_POISON_EXPR(PoisonNew(&PL_start_env, 1, JMPENV));\
69 	PL_top_env = &PL_start_env;		\
70 	PL_start_env.je_prev = NULL;		\
71 	PL_start_env.je_ret = -1;		\
72 	PL_start_env.je_mustcatch = TRUE;	\
73 	PL_start_env.je_old_delaymagic = 0;	\
74         JE_OLD_STACK_HWM_zero;                  \
75     } STMT_END
76 
77 /*
78  *   PERL_FLEXIBLE_EXCEPTIONS
79  *
80  * All the flexible exceptions code has been removed.
81  * See the following threads for details:
82  *
83  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/2004-07/msg00378.html
84  *
85  * Joshua's original patches (which weren't applied) and discussion:
86  *
87  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01396.html
88  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01489.html
89  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01491.html
90  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01608.html
91  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg02144.html
92  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg02998.html
93  *
94  * Chip's reworked patch and discussion:
95  *
96  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1999-03/msg00520.html
97  *
98  * The flaw in these patches (which went unnoticed at the time) was
99  * that they moved some code that could potentially die() out of the
100  * region protected by the setjmp()s.  This caused exceptions within
101  * END blocks and such to not be handled by the correct setjmp().
102  *
103  * The original patches that introduces flexible exceptions were:
104  *
105  * https://github.com/Perl/perl5/commit/312caa8e97f1c7ee342a9895c2f0e749625b4929
106  * https://github.com/Perl/perl5/commit/14dd3ad8c9bf82cf09798a22cc89a9862dfd6d1a
107  *
108  */
109 
110 #define dJMPENV		JMPENV cur_env
111 
112 #define JMPENV_PUSH(v) \
113     STMT_START {							\
114 	DEBUG_l({							\
115 	    int i = 0; JMPENV *p = PL_top_env;				\
116 	    while (p) { i++; p = p->je_prev; }				\
117 	    Perl_deb(aTHX_ "JUMPENV_PUSH level=%d at %s:%d\n",		\
118 		         i,  __FILE__, __LINE__);})			\
119 	cur_env.je_prev = PL_top_env;					\
120         JE_OLD_STACK_HWM_save(cur_env);                                 \
121 	cur_env.je_ret = PerlProc_setjmp(cur_env.je_buf, SCOPE_SAVES_SIGNAL_MASK);		\
122         JE_OLD_STACK_HWM_restore(cur_env);                              \
123 	PL_top_env = &cur_env;						\
124 	cur_env.je_mustcatch = FALSE;					\
125 	cur_env.je_old_delaymagic = PL_delaymagic;			\
126 	(v) = cur_env.je_ret;						\
127     } STMT_END
128 
129 #define JMPENV_POP \
130     STMT_START {							\
131 	DEBUG_l({							\
132 	    int i = -1; JMPENV *p = PL_top_env;				\
133 	    while (p) { i++; p = p->je_prev; }				\
134 	    Perl_deb(aTHX_ "JUMPENV_POP level=%d at %s:%d\n",		\
135 		         i, __FILE__, __LINE__);})			\
136 	assert(PL_top_env == &cur_env);					\
137 	PL_delaymagic = cur_env.je_old_delaymagic;			\
138 	PL_top_env = cur_env.je_prev;					\
139     } STMT_END
140 
141 #define JMPENV_JUMP(v) \
142     STMT_START {						\
143 	DEBUG_l({						\
144 	    int i = -1; JMPENV *p = PL_top_env;			\
145 	    while (p) { i++; p = p->je_prev; }			\
146 	    Perl_deb(aTHX_ "JUMPENV_JUMP(%d) level=%d at %s:%d\n", \
147 		         (int)v, i, __FILE__, __LINE__);})	\
148 	if (PL_top_env->je_prev)				\
149 	    PerlProc_longjmp(PL_top_env->je_buf, (v));		\
150 	if ((v) == 2)						\
151 	    PerlProc_exit(STATUS_EXIT);		                \
152 	PerlIO_printf(PerlIO_stderr(), "panic: top_env, v=%d\n", (int)v); \
153 	PerlProc_exit(1);					\
154     } STMT_END
155 
156 #define CATCH_GET		(PL_top_env->je_mustcatch)
157 #define CATCH_SET(v) \
158     STMT_START {							\
159 	DEBUG_l(							\
160 	    Perl_deb(aTHX_						\
161 		"JUMPLEVEL set catch %d => %d (for %p) at %s:%d\n",	\
162 		 PL_top_env->je_mustcatch, v, (void*)PL_top_env,	\
163 		 __FILE__, __LINE__);)					\
164 	PL_top_env->je_mustcatch = (v);					\
165     } STMT_END
166 
167 /*
168 =head1 COP Hint Hashes
169 */
170 
171 typedef struct refcounted_he COPHH;
172 
173 #define COPHH_KEY_UTF8 REFCOUNTED_HE_KEY_UTF8
174 
175 /*
176 =for apidoc Amx|SV *|cophh_fetch_pvn|const COPHH *cophh|const char *keypv|STRLEN keylen|U32 hash|U32 flags
177 
178 Look up the entry in the cop hints hash C<cophh> with the key specified by
179 C<keypv> and C<keylen>.  If C<flags> has the C<COPHH_KEY_UTF8> bit set,
180 the key octets are interpreted as UTF-8, otherwise they are interpreted
181 as Latin-1.  C<hash> is a precomputed hash of the key string, or zero if
182 it has not been precomputed.  Returns a mortal scalar copy of the value
183 associated with the key, or C<&PL_sv_placeholder> if there is no value
184 associated with the key.
185 
186 =cut
187 */
188 
189 #define cophh_fetch_pvn(cophh, keypv, keylen, hash, flags) \
190     Perl_refcounted_he_fetch_pvn(aTHX_ cophh, keypv, keylen, hash, flags)
191 
192 /*
193 =for apidoc Amx|SV *|cophh_fetch_pvs|const COPHH *cophh|"literal string" key|U32 flags
194 
195 Like L</cophh_fetch_pvn>, but takes a literal string instead
196 of a string/length pair, and no precomputed hash.
197 
198 =cut
199 */
200 
201 #define cophh_fetch_pvs(cophh, key, flags) \
202     Perl_refcounted_he_fetch_pvn(aTHX_ cophh, STR_WITH_LEN(key), 0, flags)
203 
204 /*
205 =for apidoc Amx|SV *|cophh_fetch_pv|const COPHH *cophh|const char *key|U32 hash|U32 flags
206 
207 Like L</cophh_fetch_pvn>, but takes a nul-terminated string instead of
208 a string/length pair.
209 
210 =cut
211 */
212 
213 #define cophh_fetch_pv(cophh, key, hash, flags) \
214     Perl_refcounted_he_fetch_pv(aTHX_ cophh, key, hash, flags)
215 
216 /*
217 =for apidoc Amx|SV *|cophh_fetch_sv|const COPHH *cophh|SV *key|U32 hash|U32 flags
218 
219 Like L</cophh_fetch_pvn>, but takes a Perl scalar instead of a
220 string/length pair.
221 
222 =cut
223 */
224 
225 #define cophh_fetch_sv(cophh, key, hash, flags) \
226     Perl_refcounted_he_fetch_sv(aTHX_ cophh, key, hash, flags)
227 
228 /*
229 =for apidoc Amx|HV *|cophh_2hv|const COPHH *cophh|U32 flags
230 
231 Generates and returns a standard Perl hash representing the full set of
232 key/value pairs in the cop hints hash C<cophh>.  C<flags> is currently
233 unused and must be zero.
234 
235 =cut
236 */
237 
238 #define cophh_2hv(cophh, flags) \
239     Perl_refcounted_he_chain_2hv(aTHX_ cophh, flags)
240 
241 /*
242 =for apidoc Amx|COPHH *|cophh_copy|COPHH *cophh
243 
244 Make and return a complete copy of the cop hints hash C<cophh>.
245 
246 =cut
247 */
248 
249 #define cophh_copy(cophh) Perl_refcounted_he_inc(aTHX_ cophh)
250 
251 /*
252 =for apidoc Amx|void|cophh_free|COPHH *cophh
253 
254 Discard the cop hints hash C<cophh>, freeing all resources associated
255 with it.
256 
257 =cut
258 */
259 
260 #define cophh_free(cophh) Perl_refcounted_he_free(aTHX_ cophh)
261 
262 /*
263 =for apidoc Amx|COPHH *|cophh_new_empty
264 
265 Generate and return a fresh cop hints hash containing no entries.
266 
267 =cut
268 */
269 
270 #define cophh_new_empty() ((COPHH *)NULL)
271 
272 /*
273 =for apidoc Amx|COPHH *|cophh_store_pvn|COPHH *cophh|const char *keypv|STRLEN keylen|U32 hash|SV *value|U32 flags
274 
275 Stores a value, associated with a key, in the cop hints hash C<cophh>,
276 and returns the modified hash.  The returned hash pointer is in general
277 not the same as the hash pointer that was passed in.  The input hash is
278 consumed by the function, and the pointer to it must not be subsequently
279 used.  Use L</cophh_copy> if you need both hashes.
280 
281 The key is specified by C<keypv> and C<keylen>.  If C<flags> has the
282 C<COPHH_KEY_UTF8> bit set, the key octets are interpreted as UTF-8,
283 otherwise they are interpreted as Latin-1.  C<hash> is a precomputed
284 hash of the key string, or zero if it has not been precomputed.
285 
286 C<value> is the scalar value to store for this key.  C<value> is copied
287 by this function, which thus does not take ownership of any reference
288 to it, and later changes to the scalar will not be reflected in the
289 value visible in the cop hints hash.  Complex types of scalar will not
290 be stored with referential integrity, but will be coerced to strings.
291 
292 =cut
293 */
294 
295 #define cophh_store_pvn(cophh, keypv, keylen, hash, value, flags) \
296     Perl_refcounted_he_new_pvn(aTHX_ cophh, keypv, keylen, hash, value, flags)
297 
298 /*
299 =for apidoc Amx|COPHH *|cophh_store_pvs|const COPHH *cophh|"literal string" key|SV *value|U32 flags
300 
301 Like L</cophh_store_pvn>, but takes a literal string instead
302 of a string/length pair, and no precomputed hash.
303 
304 =cut
305 */
306 
307 #define cophh_store_pvs(cophh, key, value, flags) \
308     Perl_refcounted_he_new_pvn(aTHX_ cophh, STR_WITH_LEN(key), 0, value, flags)
309 
310 /*
311 =for apidoc Amx|COPHH *|cophh_store_pv|const COPHH *cophh|const char *key|U32 hash|SV *value|U32 flags
312 
313 Like L</cophh_store_pvn>, but takes a nul-terminated string instead of
314 a string/length pair.
315 
316 =cut
317 */
318 
319 #define cophh_store_pv(cophh, key, hash, value, flags) \
320     Perl_refcounted_he_new_pv(aTHX_ cophh, key, hash, value, flags)
321 
322 /*
323 =for apidoc Amx|COPHH *|cophh_store_sv|const COPHH *cophh|SV *key|U32 hash|SV *value|U32 flags
324 
325 Like L</cophh_store_pvn>, but takes a Perl scalar instead of a
326 string/length pair.
327 
328 =cut
329 */
330 
331 #define cophh_store_sv(cophh, key, hash, value, flags) \
332     Perl_refcounted_he_new_sv(aTHX_ cophh, key, hash, value, flags)
333 
334 /*
335 =for apidoc Amx|COPHH *|cophh_delete_pvn|COPHH *cophh|const char *keypv|STRLEN keylen|U32 hash|U32 flags
336 
337 Delete a key and its associated value from the cop hints hash C<cophh>,
338 and returns the modified hash.  The returned hash pointer is in general
339 not the same as the hash pointer that was passed in.  The input hash is
340 consumed by the function, and the pointer to it must not be subsequently
341 used.  Use L</cophh_copy> if you need both hashes.
342 
343 The key is specified by C<keypv> and C<keylen>.  If C<flags> has the
344 C<COPHH_KEY_UTF8> bit set, the key octets are interpreted as UTF-8,
345 otherwise they are interpreted as Latin-1.  C<hash> is a precomputed
346 hash of the key string, or zero if it has not been precomputed.
347 
348 =cut
349 */
350 
351 #define cophh_delete_pvn(cophh, keypv, keylen, hash, flags) \
352     Perl_refcounted_he_new_pvn(aTHX_ cophh, keypv, keylen, hash, \
353 	(SV *)NULL, flags)
354 
355 /*
356 =for apidoc Amx|COPHH *|cophh_delete_pvs|const COPHH *cophh|"literal string" key|U32 flags
357 
358 Like L</cophh_delete_pvn>, but takes a literal string instead
359 of a string/length pair, and no precomputed hash.
360 
361 =cut
362 */
363 
364 #define cophh_delete_pvs(cophh, key, flags) \
365     Perl_refcounted_he_new_pvn(aTHX_ cophh, STR_WITH_LEN(key), 0, \
366 	(SV *)NULL, flags)
367 
368 /*
369 =for apidoc Amx|COPHH *|cophh_delete_pv|const COPHH *cophh|const char *key|U32 hash|U32 flags
370 
371 Like L</cophh_delete_pvn>, but takes a nul-terminated string instead of
372 a string/length pair.
373 
374 =cut
375 */
376 
377 #define cophh_delete_pv(cophh, key, hash, flags) \
378     Perl_refcounted_he_new_pv(aTHX_ cophh, key, hash, (SV *)NULL, flags)
379 
380 /*
381 =for apidoc Amx|COPHH *|cophh_delete_sv|const COPHH *cophh|SV *key|U32 hash|U32 flags
382 
383 Like L</cophh_delete_pvn>, but takes a Perl scalar instead of a
384 string/length pair.
385 
386 =cut
387 */
388 
389 #define cophh_delete_sv(cophh, key, hash, flags) \
390     Perl_refcounted_he_new_sv(aTHX_ cophh, key, hash, (SV *)NULL, flags)
391 
392 #include "mydtrace.h"
393 
394 struct cop {
395     BASEOP
396     /* On LP64 putting this here takes advantage of the fact that BASEOP isn't
397        an exact multiple of 8 bytes to save structure padding.  */
398     line_t      cop_line;       /* line # of this command */
399     /* label for this construct is now stored in cop_hints_hash */
400 #ifdef USE_ITHREADS
401     PADOFFSET	cop_stashoff;	/* offset into PL_stashpad, for the
402 				   package the line was compiled in */
403     char *	cop_file;	/* file name the following line # is from */
404 #else
405     HV *	cop_stash;	/* package line was compiled in */
406     GV *	cop_filegv;	/* file the following line # is from */
407 #endif
408     U32		cop_hints;	/* hints bits from pragmata */
409     U32		cop_seq;	/* parse sequence number */
410     /* Beware. mg.c and warnings.pl assume the type of this is STRLEN *:  */
411     STRLEN *	cop_warnings;	/* lexical warnings bitmask */
412     /* compile time state of %^H.  See the comment in op.c for how this is
413        used to recreate a hash to return from caller.  */
414     COPHH *	cop_hints_hash;
415 };
416 
417 #ifdef USE_ITHREADS
418 #  define CopFILE(c)		((c)->cop_file)
419 #  define CopFILEGV(c)		(CopFILE(c) \
420 				 ? gv_fetchfile(CopFILE(c)) : NULL)
421 
422 #  ifdef NETWARE
423 #    define CopFILE_set(c,pv)	((c)->cop_file = savepv(pv))
424 #    define CopFILE_setn(c,pv,l)  ((c)->cop_file = savepvn((pv),(l)))
425 #  else
426 #    define CopFILE_set(c,pv)	((c)->cop_file = savesharedpv(pv))
427 #    define CopFILE_setn(c,pv,l)  ((c)->cop_file = savesharedpvn((pv),(l)))
428 #  endif
429 
430 #  define CopFILESV(c)		(CopFILE(c) \
431 				 ? GvSV(gv_fetchfile(CopFILE(c))) : NULL)
432 #  define CopFILEAV(c)		(CopFILE(c) \
433 				 ? GvAV(gv_fetchfile(CopFILE(c))) : NULL)
434 #  define CopFILEAVx(c)		(assert_(CopFILE(c)) \
435 				   GvAV(gv_fetchfile(CopFILE(c))))
436 
437 #  define CopSTASH(c)           PL_stashpad[(c)->cop_stashoff]
438 #  define CopSTASH_set(c,hv)	((c)->cop_stashoff = (hv)		\
439 				    ? alloccopstash(hv)			\
440 				    : 0)
441 #  ifdef NETWARE
442 #    define CopFILE_free(c) SAVECOPFILE_FREE(c)
443 #  else
444 #    define CopFILE_free(c)	(PerlMemShared_free(CopFILE(c)),(CopFILE(c) = NULL))
445 #  endif
446 #else
447 #  define CopFILEGV(c)		((c)->cop_filegv)
448 #  define CopFILEGV_set(c,gv)	((c)->cop_filegv = (GV*)SvREFCNT_inc(gv))
449 #  define CopFILE_set(c,pv)	CopFILEGV_set((c), gv_fetchfile(pv))
450 #  define CopFILE_setn(c,pv,l)	CopFILEGV_set((c), gv_fetchfile_flags((pv),(l),0))
451 #  define CopFILESV(c)		(CopFILEGV(c) ? GvSV(CopFILEGV(c)) : NULL)
452 #  define CopFILEAV(c)		(CopFILEGV(c) ? GvAV(CopFILEGV(c)) : NULL)
453 #  ifdef DEBUGGING
454 #    define CopFILEAVx(c)	(assert(CopFILEGV(c)), GvAV(CopFILEGV(c)))
455 #  else
456 #    define CopFILEAVx(c)	(GvAV(CopFILEGV(c)))
457 # endif
458 #  define CopFILE(c)		(CopFILEGV(c) \
459 				    ? GvNAME(CopFILEGV(c))+2 : NULL)
460 #  define CopSTASH(c)		((c)->cop_stash)
461 #  define CopSTASH_set(c,hv)	((c)->cop_stash = (hv))
462 #  define CopFILE_free(c)	(SvREFCNT_dec(CopFILEGV(c)),(CopFILEGV(c) = NULL))
463 
464 #endif /* USE_ITHREADS */
465 
466 #define CopSTASHPV(c)		(CopSTASH(c) ? HvNAME_get(CopSTASH(c)) : NULL)
467    /* cop_stash is not refcounted */
468 #define CopSTASHPV_set(c,pv)	CopSTASH_set((c), gv_stashpv(pv,GV_ADD))
469 #define CopSTASH_eq(c,hv)	(CopSTASH(c) == (hv))
470 
471 #define CopHINTHASH_get(c)	((COPHH*)((c)->cop_hints_hash))
472 #define CopHINTHASH_set(c,h)	((c)->cop_hints_hash = (h))
473 
474 /*
475 =head1 COP Hint Reading
476 */
477 
478 /*
479 =for apidoc Am|SV *|cop_hints_fetch_pvn|const COP *cop|const char *keypv|STRLEN keylen|U32 hash|U32 flags
480 
481 Look up the hint entry in the cop C<cop> with the key specified by
482 C<keypv> and C<keylen>.  If C<flags> has the C<COPHH_KEY_UTF8> bit set,
483 the key octets are interpreted as UTF-8, otherwise they are interpreted
484 as Latin-1.  C<hash> is a precomputed hash of the key string, or zero if
485 it has not been precomputed.  Returns a mortal scalar copy of the value
486 associated with the key, or C<&PL_sv_placeholder> if there is no value
487 associated with the key.
488 
489 =cut
490 */
491 
492 #define cop_hints_fetch_pvn(cop, keypv, keylen, hash, flags) \
493     cophh_fetch_pvn(CopHINTHASH_get(cop), keypv, keylen, hash, flags)
494 
495 /*
496 =for apidoc Am|SV *|cop_hints_fetch_pvs|const COP *cop|"literal string" key|U32 flags
497 
498 Like L</cop_hints_fetch_pvn>, but takes a literal string
499 instead of a string/length pair, and no precomputed hash.
500 
501 =cut
502 */
503 
504 #define cop_hints_fetch_pvs(cop, key, flags) \
505     cophh_fetch_pvs(CopHINTHASH_get(cop), key, flags)
506 
507 /*
508 =for apidoc Am|SV *|cop_hints_fetch_pv|const COP *cop|const char *key|U32 hash|U32 flags
509 
510 Like L</cop_hints_fetch_pvn>, but takes a nul-terminated string instead
511 of a string/length pair.
512 
513 =cut
514 */
515 
516 #define cop_hints_fetch_pv(cop, key, hash, flags) \
517     cophh_fetch_pv(CopHINTHASH_get(cop), key, hash, flags)
518 
519 /*
520 =for apidoc Am|SV *|cop_hints_fetch_sv|const COP *cop|SV *key|U32 hash|U32 flags
521 
522 Like L</cop_hints_fetch_pvn>, but takes a Perl scalar instead of a
523 string/length pair.
524 
525 =cut
526 */
527 
528 #define cop_hints_fetch_sv(cop, key, hash, flags) \
529     cophh_fetch_sv(CopHINTHASH_get(cop), key, hash, flags)
530 
531 /*
532 =for apidoc Am|HV *|cop_hints_2hv|const COP *cop|U32 flags
533 
534 Generates and returns a standard Perl hash representing the full set of
535 hint entries in the cop C<cop>.  C<flags> is currently unused and must
536 be zero.
537 
538 =cut
539 */
540 
541 #define cop_hints_2hv(cop, flags) \
542     cophh_2hv(CopHINTHASH_get(cop), flags)
543 
544 #define CopLABEL(c)  Perl_cop_fetch_label(aTHX_ (c), NULL, NULL)
545 #define CopLABEL_len(c,len)  Perl_cop_fetch_label(aTHX_ (c), len, NULL)
546 #define CopLABEL_len_flags(c,len,flags)  Perl_cop_fetch_label(aTHX_ (c), len, flags)
547 #define CopLABEL_alloc(pv)	((pv)?savepv(pv):NULL)
548 
549 #define CopSTASH_ne(c,hv)	(!CopSTASH_eq(c,hv))
550 #define CopLINE(c)		((c)->cop_line)
551 #define CopLINE_inc(c)		(++CopLINE(c))
552 #define CopLINE_dec(c)		(--CopLINE(c))
553 #define CopLINE_set(c,l)	(CopLINE(c) = (l))
554 
555 /* OutCopFILE() is CopFILE for output (caller, die, warn, etc.) */
556 #define OutCopFILE(c) CopFILE(c)
557 
558 #define CopHINTS_get(c)		((c)->cop_hints + 0)
559 #define CopHINTS_set(c, h)	STMT_START {				\
560 				    (c)->cop_hints = (h);		\
561 				} STMT_END
562 
563 /*
564  * Here we have some enormously heavy (or at least ponderous) wizardry.
565  */
566 
567 /* subroutine context */
568 struct block_sub {
569     OP *	retop;	/* op to execute on exit from sub */
570     /* Above here is the same for sub, format and eval.  */
571     PAD		*prevcomppad; /* the caller's PL_comppad */
572     CV *	cv;
573     /* Above here is the same for sub and format.  */
574     I32		olddepth;
575     AV  	*savearray;
576 };
577 
578 
579 /* format context */
580 struct block_format {
581     OP *	retop;	/* op to execute on exit from sub */
582     /* Above here is the same for sub, format and eval.  */
583     PAD		*prevcomppad; /* the caller's PL_comppad */
584     CV *	cv;
585     /* Above here is the same for sub and format.  */
586     GV *	gv;
587     GV *	dfoutgv;
588 };
589 
590 /* return a pointer to the current context */
591 
592 #define CX_CUR() (&cxstack[cxstack_ix])
593 
594 /* free all savestack items back to the watermark of the specified context */
595 
596 #define CX_LEAVE_SCOPE(cx) LEAVE_SCOPE(cx->blk_oldsaveix)
597 
598 #ifdef DEBUGGING
599 /* on debugging builds, poison cx afterwards so we know no code
600  * uses it - because after doing cxstack_ix--, any ties, exceptions etc
601  * may overwrite the current stack frame */
602 #  define CX_POP(cx)                                                   \
603         assert(CX_CUR() == cx);                                        \
604         cxstack_ix--;                                                  \
605         cx = NULL;
606 #else
607 #  define CX_POP(cx) cxstack_ix--;
608 #endif
609 
610 
611 /* base for the next two macros. Don't use directly.
612  * The context frame holds a reference to the CV so that it can't be
613  * freed while we're executing it */
614 
615 
616 #define CX_PUSHSUB_GET_LVALUE_MASK(func) \
617 	/* If the context is indeterminate, then only the lvalue */	\
618 	/* flags that the caller also has are applicable.        */	\
619 	(								\
620 	   (PL_op->op_flags & OPf_WANT)					\
621 	       ? OPpENTERSUB_LVAL_MASK					\
622 	       : !(PL_op->op_private & OPpENTERSUB_LVAL_MASK)		\
623 	           ? 0 : (U8)func(aTHX)					\
624 	)
625 
626 /* Restore old @_ */
627 #define CX_POP_SAVEARRAY(cx)						\
628     STMT_START {							\
629         AV *cx_pop_savearray_av = GvAV(PL_defgv);                       \
630 	GvAV(PL_defgv) = cx->blk_sub.savearray;				\
631         cx->blk_sub.savearray = NULL;                                   \
632         SvREFCNT_dec(cx_pop_savearray_av);	 			\
633     } STMT_END
634 
635 /* junk in @_ spells trouble when cloning CVs and in pp_caller(), so don't
636  * leave any (a fast av_clear(ary), basically) */
637 #define CLEAR_ARGARRAY(ary) \
638     STMT_START {							\
639 	AvMAX(ary) += AvARRAY(ary) - AvALLOC(ary);			\
640 	AvARRAY(ary) = AvALLOC(ary);					\
641 	AvFILLp(ary) = -1;						\
642     } STMT_END
643 
644 
645 /* eval context */
646 struct block_eval {
647     OP *	retop;	/* op to execute on exit from eval */
648     /* Above here is the same for sub, format and eval.  */
649     SV *	old_namesv;
650     OP *	old_eval_root;
651     SV *	cur_text;
652     CV *	cv;
653     JMPENV *	cur_top_env; /* value of PL_top_env when eval CX created */
654 };
655 
656 /* If we ever need more than 512 op types, change the shift from 7.
657    blku_gimme is actually also only 2 bits, so could be merged with something.
658 */
659 
660 /* blk_u16 bit usage for eval contexts: */
661 
662 #define CxOLD_IN_EVAL(cx)	(((cx)->blk_u16) & 0x3F) /* saved PL in_eval */
663 #define CxEVAL_TXT_REFCNTED(cx)	(((cx)->blk_u16) & 0x40) /* cur_text rc++ */
664 #define CxOLD_OP_TYPE(cx)	(((cx)->blk_u16) >> 7)   /* type of eval op */
665 
666 /* loop context */
667 struct block_loop {
668     LOOP *	my_op;	/* My op, that contains redo, next and last ops.  */
669     union {	/* different ways of locating the iteration variable */
670 	SV      **svp; /* for lexicals: address of pad slot */
671 	GV      *gv;   /* for package vars */
672     } itervar_u;
673     SV          *itersave; /* the original iteration var */
674     union {
675 	struct { /* CXt_LOOP_ARY, C<for (@ary)>  */
676 	    AV *ary; /* array being iterated over */
677 	    IV  ix;   /* index relative to base of array */
678 	} ary;
679 	struct { /* CXt_LOOP_LIST, C<for (list)> */
680 	    I32 basesp; /* first element of list on stack */
681 	    IV  ix;      /* index relative to basesp */
682 	} stack;
683 	struct { /* CXt_LOOP_LAZYIV, C<for (1..9)> */
684 	    IV cur;
685 	    IV end;
686 	} lazyiv;
687 	struct { /* CXt_LOOP_LAZYSV C<for ('a'..'z')> */
688 	    SV * cur;
689 	    SV * end; /* maxiumum value (or minimum in reverse) */
690 	} lazysv;
691     } state_u;
692 #ifdef USE_ITHREADS
693     PAD *oldcomppad; /* needed to map itervar_u.svp during thread clone */
694 #endif
695 };
696 
697 #define CxITERVAR(c)                                    \
698         (CxPADLOOP(c)                                   \
699             ? (c)->blk_loop.itervar_u.svp               \
700             : ((c)->cx_type & CXp_FOR_GV)               \
701                 ? &GvSV((c)->blk_loop.itervar_u.gv)     \
702                 : (SV **)&(c)->blk_loop.itervar_u.gv)
703 
704 #define CxLABEL(c)	(0 + CopLABEL((c)->blk_oldcop))
705 #define CxLABEL_len(c,len)	(0 + CopLABEL_len((c)->blk_oldcop, len))
706 #define CxLABEL_len_flags(c,len,flags)	(0 + CopLABEL_len_flags((c)->blk_oldcop, len, flags))
707 #define CxHASARGS(c)	(((c)->cx_type & CXp_HASARGS) == CXp_HASARGS)
708 
709 /* CxLVAL(): the lval flags of the call site: the relevant flag bits from
710  * the op_private field of the calling pp_entersub (or its caller's caller
711  * if the caller's lvalue context isn't known):
712  *  OPpLVAL_INTRO:  sub used in lvalue context, e.g. f() = 1;
713  *  OPpENTERSUB_INARGS (in conjunction with OPpLVAL_INTRO): the
714  *      function is being used as a sub arg or as a referent, e.g.
715  *      g(...,f(),...)  or $r = \f()
716  *  OPpDEREF: 2-bit mask indicating e.g. f()->[0].
717  *  Note the contrast with CvLVALUE(), which is a property of the sub
718  *  rather than the call site.
719  */
720 #define CxLVAL(c)	(0 + ((c)->blk_u16 & 0xff))
721 
722 
723 
724 /* given/when context */
725 struct block_givwhen {
726 	OP *leave_op;
727         SV *defsv_save; /* the original $_ */
728 };
729 
730 
731 
732 /* context common to subroutines, evals and loops */
733 struct block {
734     U8		blku_type;	/* what kind of context this is */
735     U8		blku_gimme;	/* is this block running in list context? */
736     U16		blku_u16;	/* used by block_sub and block_eval (so far) */
737     I32		blku_oldsaveix; /* saved PL_savestack_ix */
738     /* all the fields above must be aligned with same-sized fields as sbu */
739     I32		blku_oldsp;	/* current sp floor: where nextstate pops to */
740     I32		blku_oldmarksp;	/* mark stack index */
741     COP *	blku_oldcop;	/* old curcop pointer */
742     PMOP *	blku_oldpm;	/* values of pattern match vars */
743     SSize_t     blku_old_tmpsfloor;     /* saved PL_tmps_floor */
744     I32		blku_oldscopesp;	/* scope stack index */
745 
746     union {
747 	struct block_sub	blku_sub;
748 	struct block_format	blku_format;
749 	struct block_eval	blku_eval;
750 	struct block_loop	blku_loop;
751 	struct block_givwhen	blku_givwhen;
752     } blk_u;
753 };
754 #define blk_oldsp	cx_u.cx_blk.blku_oldsp
755 #define blk_oldcop	cx_u.cx_blk.blku_oldcop
756 #define blk_oldmarksp	cx_u.cx_blk.blku_oldmarksp
757 #define blk_oldscopesp	cx_u.cx_blk.blku_oldscopesp
758 #define blk_oldpm	cx_u.cx_blk.blku_oldpm
759 #define blk_gimme	cx_u.cx_blk.blku_gimme
760 #define blk_u16		cx_u.cx_blk.blku_u16
761 #define blk_oldsaveix   cx_u.cx_blk.blku_oldsaveix
762 #define blk_old_tmpsfloor cx_u.cx_blk.blku_old_tmpsfloor
763 #define blk_sub		cx_u.cx_blk.blk_u.blku_sub
764 #define blk_format	cx_u.cx_blk.blk_u.blku_format
765 #define blk_eval	cx_u.cx_blk.blk_u.blku_eval
766 #define blk_loop	cx_u.cx_blk.blk_u.blku_loop
767 #define blk_givwhen	cx_u.cx_blk.blk_u.blku_givwhen
768 
769 #define CX_DEBUG(cx, action)						\
770     DEBUG_l(								\
771 	Perl_deb(aTHX_ "CX %ld %s %s (scope %ld,%ld) (save %ld,%ld) at %s:%d\n",\
772 		    (long)cxstack_ix,					\
773 		    action,						\
774 		    PL_block_type[CxTYPE(cx)],	                        \
775 		    (long)PL_scopestack_ix,				\
776 		    (long)(cx->blk_oldscopesp),		                \
777 		    (long)PL_savestack_ix,				\
778 		    (long)(cx->blk_oldsaveix),                          \
779 		    __FILE__, __LINE__));
780 
781 
782 
783 /* substitution context */
784 struct subst {
785     U8		sbu_type;	/* same as blku_type */
786     U8		sbu_rflags;
787     U16		sbu_rxtainted;
788     I32		sbu_oldsaveix; /* same as blku_oldsaveix */
789     /* all the fields above must be aligned with same-sized fields as blk_u */
790     SSize_t	sbu_iters;
791     SSize_t	sbu_maxiters;
792     char *	sbu_orig;
793     SV *	sbu_dstr;
794     SV *	sbu_targ;
795     char *	sbu_s;
796     char *	sbu_m;
797     char *	sbu_strend;
798     void *	sbu_rxres;
799     REGEXP *	sbu_rx;
800 };
801 #define sb_iters	cx_u.cx_subst.sbu_iters
802 #define sb_maxiters	cx_u.cx_subst.sbu_maxiters
803 #define sb_rflags	cx_u.cx_subst.sbu_rflags
804 #define sb_rxtainted	cx_u.cx_subst.sbu_rxtainted
805 #define sb_orig		cx_u.cx_subst.sbu_orig
806 #define sb_dstr		cx_u.cx_subst.sbu_dstr
807 #define sb_targ		cx_u.cx_subst.sbu_targ
808 #define sb_s		cx_u.cx_subst.sbu_s
809 #define sb_m		cx_u.cx_subst.sbu_m
810 #define sb_strend	cx_u.cx_subst.sbu_strend
811 #define sb_rxres	cx_u.cx_subst.sbu_rxres
812 #define sb_rx		cx_u.cx_subst.sbu_rx
813 
814 #ifdef PERL_CORE
815 #  define CX_PUSHSUBST(cx) CXINC, cx = CX_CUR(),		        \
816 	cx->blk_oldsaveix = oldsave,				        \
817 	cx->sb_iters		= iters,				\
818 	cx->sb_maxiters		= maxiters,				\
819 	cx->sb_rflags		= r_flags,				\
820 	cx->sb_rxtainted	= rxtainted,				\
821 	cx->sb_orig		= orig,					\
822 	cx->sb_dstr		= dstr,					\
823 	cx->sb_targ		= targ,					\
824 	cx->sb_s		= s,					\
825 	cx->sb_m		= m,					\
826 	cx->sb_strend		= strend,				\
827 	cx->sb_rxres		= NULL,					\
828 	cx->sb_rx		= rx,					\
829 	cx->cx_type		= CXt_SUBST | (once ? CXp_ONCE : 0);	\
830 	rxres_save(&cx->sb_rxres, rx);					\
831 	(void)ReREFCNT_inc(rx);						\
832         SvREFCNT_inc_void_NN(targ)
833 
834 #  define CX_POPSUBST(cx) \
835     STMT_START {							\
836         REGEXP *re;                                                     \
837         assert(CxTYPE(cx) == CXt_SUBST);                                \
838 	rxres_free(&cx->sb_rxres);					\
839 	re = cx->sb_rx;                                                 \
840 	cx->sb_rx = NULL;                                               \
841 	ReREFCNT_dec(re);                                               \
842         SvREFCNT_dec_NN(cx->sb_targ);                                   \
843     } STMT_END
844 #endif
845 
846 #define CxONCE(cx)		((cx)->cx_type & CXp_ONCE)
847 
848 struct context {
849     union {
850 	struct block	cx_blk;
851 	struct subst	cx_subst;
852     } cx_u;
853 };
854 #define cx_type cx_u.cx_subst.sbu_type
855 
856 /* If you re-order these, there is also an array of uppercase names in perl.h
857    and a static array of context names in pp_ctl.c  */
858 #define CXTYPEMASK	0xf
859 #define CXt_NULL	0 /* currently only used for sort BLOCK */
860 #define CXt_WHEN	1
861 #define CXt_BLOCK	2
862 /* When micro-optimising :-) keep GIVEN next to the LOOPs, as these 5 share a
863    jump table in pp_ctl.c
864    The first 4 don't have a 'case' in at least one switch statement in pp_ctl.c
865 */
866 #define CXt_GIVEN	3
867 
868 /* be careful of the ordering of these five. Macros like CxTYPE_is_LOOP,
869  * CxFOREACH compare ranges */
870 #define CXt_LOOP_ARY	4 /* for (@ary)     { ...; } */
871 #define CXt_LOOP_LAZYSV	5 /* for ('a'..'z') { ...; } */
872 #define CXt_LOOP_LAZYIV	6 /* for (1..9)     { ...; } */
873 #define CXt_LOOP_LIST	7 /* for (1,2,3)    { ...; } */
874 #define CXt_LOOP_PLAIN	8 /* while (...)    { ...; }
875                              or plain block { ...; } */
876 #define CXt_SUB		9
877 #define CXt_FORMAT     10
878 #define CXt_EVAL       11
879 #define CXt_SUBST      12
880 /* SUBST doesn't feature in all switch statements.  */
881 
882 /* private flags for CXt_SUB and CXt_FORMAT */
883 #define CXp_MULTICALL	0x10	/* part of a multicall (so don't tear down
884                                    context on exit). (not CXt_FORMAT) */
885 #define CXp_HASARGS	0x20
886 #define CXp_SUB_RE	0x40    /* code called within regex, i.e. (?{}) */
887 #define CXp_SUB_RE_FAKE	0x80    /* fake sub CX for (?{}) in current scope */
888 
889 /* private flags for CXt_EVAL */
890 #define CXp_REAL	0x20	/* truly eval'', not a lookalike */
891 #define CXp_TRYBLOCK	0x40	/* eval{}, not eval'' or similar */
892 
893 /* private flags for CXt_LOOP */
894 
895 /* this is only set in conjunction with CXp_FOR_GV */
896 #define CXp_FOR_DEF	0x10	/* foreach using $_ */
897 /* these 3 are mutually exclusive */
898 #define CXp_FOR_LVREF	0x20	/* foreach using \$var */
899 #define CXp_FOR_GV	0x40	/* foreach using package var */
900 #define CXp_FOR_PAD	0x80	/* foreach using lexical var */
901 
902 #define CxPADLOOP(c)	((c)->cx_type & CXp_FOR_PAD)
903 
904 /* private flags for CXt_SUBST */
905 #define CXp_ONCE	0x10	/* What was sbu_once in struct subst */
906 
907 #define CxTYPE(c)	((c)->cx_type & CXTYPEMASK)
908 #define CxTYPE_is_LOOP(c) (   CxTYPE(cx) >= CXt_LOOP_ARY                \
909                            && CxTYPE(cx) <= CXt_LOOP_PLAIN)
910 #define CxMULTICALL(c)	((c)->cx_type & CXp_MULTICALL)
911 #define CxREALEVAL(c)	(((c)->cx_type & (CXTYPEMASK|CXp_REAL))		\
912 			 == (CXt_EVAL|CXp_REAL))
913 #define CxTRYBLOCK(c)	(((c)->cx_type & (CXTYPEMASK|CXp_TRYBLOCK))	\
914 			 == (CXt_EVAL|CXp_TRYBLOCK))
915 #define CxFOREACH(c)	(   CxTYPE(cx) >= CXt_LOOP_ARY                  \
916                          && CxTYPE(cx) <= CXt_LOOP_LIST)
917 
918 #define CXINC (cxstack_ix < cxstack_max ? ++cxstack_ix : (cxstack_ix = cxinc()))
919 
920 /*
921 =head1 "Gimme" Values
922 */
923 
924 /*
925 =for apidoc AmU||G_SCALAR
926 Used to indicate scalar context.  See C<L</GIMME_V>>, C<L</GIMME>>, and
927 L<perlcall>.
928 
929 =for apidoc AmU||G_ARRAY
930 Used to indicate list context.  See C<L</GIMME_V>>, C<L</GIMME>> and
931 L<perlcall>.
932 
933 =for apidoc AmU||G_VOID
934 Used to indicate void context.  See C<L</GIMME_V>> and L<perlcall>.
935 
936 =for apidoc AmU||G_DISCARD
937 Indicates that arguments returned from a callback should be discarded.  See
938 L<perlcall>.
939 
940 =for apidoc AmU||G_EVAL
941 
942 Used to force a Perl C<eval> wrapper around a callback.  See
943 L<perlcall>.
944 
945 =for apidoc AmU||G_NOARGS
946 
947 Indicates that no arguments are being sent to a callback.  See
948 L<perlcall>.
949 
950 =cut
951 */
952 
953 #define G_SCALAR	2
954 #define G_ARRAY		3
955 #define G_VOID		1
956 #define G_WANT		3
957 
958 /* extra flags for Perl_call_* routines */
959 #define G_DISCARD	4	/* Call FREETMPS.
960 				   Don't change this without consulting the
961 				   hash actions codes defined in hv.h */
962 #define G_EVAL		8	/* Assume eval {} around subroutine call. */
963 #define G_NOARGS       16	/* Don't construct a @_ array. */
964 #define G_KEEPERR      32	/* Warn for errors, don't overwrite $@ */
965 #define G_NODEBUG      64	/* Disable debugging at toplevel.  */
966 #define G_METHOD      128       /* Calling method. */
967 #define G_FAKINGEVAL  256	/* Faking an eval context for call_sv or
968 				   fold_constants. */
969 #define G_UNDEF_FILL  512	/* Fill the stack with &PL_sv_undef
970 				   A special case for UNSHIFT in
971 				   Perl_magic_methcall().  */
972 #define G_WRITING_TO_STDERR 1024 /* Perl_write_to_stderr() is calling
973 				    Perl_magic_methcall().  */
974 #define G_RE_REPARSING 0x800     /* compiling a run-time /(?{..})/ */
975 #define G_METHOD_NAMED 4096	/* calling named method, eg without :: or ' */
976 
977 /* flag bits for PL_in_eval */
978 #define EVAL_NULL	0	/* not in an eval */
979 #define EVAL_INEVAL	1	/* some enclosing scope is an eval */
980 #define EVAL_WARNONLY	2	/* used by yywarn() when calling yyerror() */
981 #define EVAL_KEEPERR	4	/* set by Perl_call_sv if G_KEEPERR */
982 #define EVAL_INREQUIRE	8	/* The code is being required. */
983 #define EVAL_RE_REPARSING 0x10	/* eval_sv() called with G_RE_REPARSING */
984 /* if adding extra bits, make sure they can fit in CxOLD_OP_TYPE() */
985 
986 /* Support for switching (stack and block) contexts.
987  * This ensures magic doesn't invalidate local stack and cx pointers.
988  */
989 
990 #define PERLSI_UNKNOWN		-1
991 #define PERLSI_UNDEF		0
992 #define PERLSI_MAIN		1
993 #define PERLSI_MAGIC		2
994 #define PERLSI_SORT		3
995 #define PERLSI_SIGNAL		4
996 #define PERLSI_OVERLOAD		5
997 #define PERLSI_DESTROY		6
998 #define PERLSI_WARNHOOK		7
999 #define PERLSI_DIEHOOK		8
1000 #define PERLSI_REQUIRE		9
1001 #define PERLSI_MULTICALL       10
1002 
1003 struct stackinfo {
1004     AV *		si_stack;	/* stack for current runlevel */
1005     PERL_CONTEXT *	si_cxstack;	/* context stack for runlevel */
1006     struct stackinfo *	si_prev;
1007     struct stackinfo *	si_next;
1008     I32			si_cxix;	/* current context index */
1009     I32			si_cxmax;	/* maximum allocated index */
1010     I32			si_type;	/* type of runlevel */
1011     I32			si_markoff;	/* offset where markstack begins for us.
1012 					 * currently used only with DEBUGGING,
1013 					 * but not #ifdef-ed for bincompat */
1014 #if defined DEBUGGING && !defined DEBUGGING_RE_ONLY
1015 /* high water mark: for checking if the stack was correctly extended /
1016  * tested for extension by each pp function */
1017     SSize_t             si_stack_hwm;
1018 #endif
1019 
1020 };
1021 
1022 typedef struct stackinfo PERL_SI;
1023 
1024 #define cxstack		(PL_curstackinfo->si_cxstack)
1025 #define cxstack_ix	(PL_curstackinfo->si_cxix)
1026 #define cxstack_max	(PL_curstackinfo->si_cxmax)
1027 
1028 #ifdef DEBUGGING
1029 #  define	SET_MARK_OFFSET \
1030     PL_curstackinfo->si_markoff = PL_markstack_ptr - PL_markstack
1031 #else
1032 #  define	SET_MARK_OFFSET NOOP
1033 #endif
1034 
1035 #if defined DEBUGGING && !defined DEBUGGING_RE_ONLY
1036 #  define PUSHSTACK_INIT_HWM(si) ((si)->si_stack_hwm = 0)
1037 #else
1038 #  define PUSHSTACK_INIT_HWM(si) NOOP
1039 #endif
1040 
1041 #define PUSHSTACKi(type) \
1042     STMT_START {							\
1043 	PERL_SI *next = PL_curstackinfo->si_next;			\
1044 	DEBUG_l({							\
1045 	    int i = 0; PERL_SI *p = PL_curstackinfo;			\
1046 	    while (p) { i++; p = p->si_prev; }				\
1047 	    Perl_deb(aTHX_ "push STACKINFO %d at %s:%d\n",		\
1048 		         i, __FILE__, __LINE__);})			\
1049 	if (!next) {							\
1050 	    next = new_stackinfo(32, 2048/sizeof(PERL_CONTEXT) - 1);	\
1051 	    next->si_prev = PL_curstackinfo;				\
1052 	    PL_curstackinfo->si_next = next;				\
1053 	}								\
1054 	next->si_type = type;						\
1055 	next->si_cxix = -1;						\
1056         PUSHSTACK_INIT_HWM(next);                                       \
1057 	AvFILLp(next->si_stack) = 0;					\
1058 	SWITCHSTACK(PL_curstack,next->si_stack);			\
1059 	PL_curstackinfo = next;						\
1060 	SET_MARK_OFFSET;						\
1061     } STMT_END
1062 
1063 #define PUSHSTACK PUSHSTACKi(PERLSI_UNKNOWN)
1064 
1065 /* POPSTACK works with PL_stack_sp, so it may need to be bracketed by
1066  * PUTBACK/SPAGAIN to flush/refresh any local SP that may be active */
1067 #define POPSTACK \
1068     STMT_START {							\
1069 	dSP;								\
1070 	PERL_SI * const prev = PL_curstackinfo->si_prev;		\
1071 	DEBUG_l({							\
1072 	    int i = -1; PERL_SI *p = PL_curstackinfo;			\
1073 	    while (p) { i++; p = p->si_prev; }				\
1074 	    Perl_deb(aTHX_ "pop  STACKINFO %d at %s:%d\n",		\
1075 		         i, __FILE__, __LINE__);})			\
1076 	if (!prev) {							\
1077 	    Perl_croak_popstack();					\
1078 	}								\
1079 	SWITCHSTACK(PL_curstack,prev->si_stack);			\
1080 	/* don't free prev here, free them all at the END{} */		\
1081 	PL_curstackinfo = prev;						\
1082     } STMT_END
1083 
1084 #define POPSTACK_TO(s) \
1085     STMT_START {							\
1086 	while (PL_curstack != s) {					\
1087 	    dounwind(-1);						\
1088 	    POPSTACK;							\
1089 	}								\
1090     } STMT_END
1091 
1092 #define IN_PERL_COMPILETIME	cBOOL(PL_curcop == &PL_compiling)
1093 #define IN_PERL_RUNTIME		cBOOL(PL_curcop != &PL_compiling)
1094 
1095 
1096 
1097 
1098 /*
1099 =head1 Multicall Functions
1100 
1101 =for apidoc Ams||dMULTICALL
1102 Declare local variables for a multicall.  See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1103 
1104 =for apidoc Ams||PUSH_MULTICALL
1105 Opening bracket for a lightweight callback.
1106 See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1107 
1108 =for apidoc Ams||MULTICALL
1109 Make a lightweight callback.  See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1110 
1111 =for apidoc Ams||POP_MULTICALL
1112 Closing bracket for a lightweight callback.
1113 See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1114 
1115 =cut
1116 */
1117 
1118 #define dMULTICALL \
1119     OP  *multicall_cop;							\
1120     bool multicall_oldcatch
1121 
1122 #define PUSH_MULTICALL(the_cv) \
1123     PUSH_MULTICALL_FLAGS(the_cv, 0)
1124 
1125 /* Like PUSH_MULTICALL, but allows you to specify extra flags
1126  * for the CX stack entry (this isn't part of the public API) */
1127 
1128 #define PUSH_MULTICALL_FLAGS(the_cv, flags) \
1129     STMT_START {							\
1130         PERL_CONTEXT *cx;						\
1131 	CV * const _nOnclAshIngNamE_ = the_cv;				\
1132 	CV * const cv = _nOnclAshIngNamE_;				\
1133 	PADLIST * const padlist = CvPADLIST(cv);			\
1134  	multicall_oldcatch = CATCH_GET;					\
1135 	CATCH_SET(TRUE);						\
1136 	PUSHSTACKi(PERLSI_MULTICALL);					\
1137 	cx = cx_pushblock((CXt_SUB|CXp_MULTICALL|flags), (U8)gimme,     \
1138                   PL_stack_sp, PL_savestack_ix);	                \
1139         cx_pushsub(cx, cv, NULL, 0);                                    \
1140 	SAVEOP();					                \
1141         if (!(flags & CXp_SUB_RE_FAKE))                                 \
1142             CvDEPTH(cv)++;						\
1143 	if (CvDEPTH(cv) >= 2)  						\
1144 	    Perl_pad_push(aTHX_ padlist, CvDEPTH(cv));			\
1145 	PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));			\
1146 	multicall_cop = CvSTART(cv);					\
1147     } STMT_END
1148 
1149 #define MULTICALL \
1150     STMT_START {							\
1151 	PL_op = multicall_cop;						\
1152 	CALLRUNOPS(aTHX);						\
1153     } STMT_END
1154 
1155 #define POP_MULTICALL \
1156     STMT_START {							\
1157         PERL_CONTEXT *cx;						\
1158 	cx = CX_CUR();					                \
1159 	CX_LEAVE_SCOPE(cx);                                             \
1160         cx_popsub_common(cx);                                           \
1161         gimme = cx->blk_gimme;                                          \
1162         PERL_UNUSED_VAR(gimme); /* for API */                           \
1163 	cx_popblock(cx);				   		\
1164 	CX_POP(cx);                                                     \
1165 	POPSTACK;							\
1166 	CATCH_SET(multicall_oldcatch);					\
1167 	SPAGAIN;							\
1168     } STMT_END
1169 
1170 /* Change the CV of an already-pushed MULTICALL CxSUB block.
1171  * (this isn't part of the public API) */
1172 
1173 #define CHANGE_MULTICALL_FLAGS(the_cv, flags) \
1174     STMT_START {							\
1175 	CV * const _nOnclAshIngNamE_ = the_cv;				\
1176 	CV * const cv = _nOnclAshIngNamE_;				\
1177 	PADLIST * const padlist = CvPADLIST(cv);			\
1178         PERL_CONTEXT *cx = CX_CUR();					\
1179 	assert(CxMULTICALL(cx));                                        \
1180         cx_popsub_common(cx);                                           \
1181 	cx->cx_type = (CXt_SUB|CXp_MULTICALL|flags);                    \
1182         cx_pushsub(cx, cv, NULL, 0);			                \
1183         if (!(flags & CXp_SUB_RE_FAKE))                                 \
1184             CvDEPTH(cv)++;						\
1185 	if (CvDEPTH(cv) >= 2)  						\
1186 	    Perl_pad_push(aTHX_ padlist, CvDEPTH(cv));			\
1187 	PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));			\
1188 	multicall_cop = CvSTART(cv);					\
1189     } STMT_END
1190 /*
1191  * ex: set ts=8 sts=4 sw=4 et:
1192  */
1193