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[perl #118907] bump $Storable::VERSION
[perl5.git] / cop.h
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 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 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;         /* only for use if !je_throw */
35     int                 je_ret;         /* last exception thrown */
36     bool                je_mustcatch;   /* need to call longjmp()? */
37 };
38
39 typedef struct jmpenv JMPENV;
40
41 #ifdef OP_IN_REGISTER
42 #define OP_REG_TO_MEM   PL_opsave = op
43 #define OP_MEM_TO_REG   op = PL_opsave
44 #else
45 #define OP_REG_TO_MEM   NOOP
46 #define OP_MEM_TO_REG   NOOP
47 #endif
48
49 /*
50  * How to build the first jmpenv.
51  *
52  * top_env needs to be non-zero. It points to an area
53  * in which longjmp() stuff is stored, as C callstack
54  * info there at least is thread specific this has to
55  * be per-thread. Otherwise a 'die' in a thread gives
56  * that thread the C stack of last thread to do an eval {}!
57  */
58
59 #define JMPENV_BOOTSTRAP \
60     STMT_START {                                \
61         Zero(&PL_start_env, 1, JMPENV);         \
62         PL_start_env.je_ret = -1;               \
63         PL_start_env.je_mustcatch = TRUE;       \
64         PL_top_env = &PL_start_env;             \
65     } STMT_END
66
67 /*
68  *   PERL_FLEXIBLE_EXCEPTIONS
69  * 
70  * All the flexible exceptions code has been removed.
71  * See the following threads for details:
72  *
73  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/2004-07/msg00378.html
74  * 
75  * Joshua's original patches (which weren't applied) and discussion:
76  * 
77  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01396.html
78  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01489.html
79  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01491.html
80  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01608.html
81  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg02144.html
82  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg02998.html
83  * 
84  * Chip's reworked patch and discussion:
85  * 
86  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1999-03/msg00520.html
87  * 
88  * The flaw in these patches (which went unnoticed at the time) was
89  * that they moved some code that could potentially die() out of the
90  * region protected by the setjmp()s.  This caused exceptions within
91  * END blocks and such to not be handled by the correct setjmp().
92  * 
93  * The original patches that introduces flexible exceptions were:
94  *
95  * http://perl5.git.perl.org/perl.git/commit/312caa8e97f1c7ee342a9895c2f0e749625b4929
96  * http://perl5.git.perl.org/perl.git/commit/14dd3ad8c9bf82cf09798a22cc89a9862dfd6d1a                                        
97  *  
98  */
99
100 #define dJMPENV         JMPENV cur_env
101
102 #define JMPENV_PUSH(v) \
103     STMT_START {                                                        \
104         DEBUG_l({                                                       \
105             int i = 0; JMPENV *p = PL_top_env;                          \
106             while (p) { i++; p = p->je_prev; }                          \
107             Perl_deb(aTHX_ "JUMPENV_PUSH level=%d at %s:%d\n",          \
108                          i,  __FILE__, __LINE__);})                     \
109         cur_env.je_prev = PL_top_env;                                   \
110         OP_REG_TO_MEM;                                                  \
111         cur_env.je_ret = PerlProc_setjmp(cur_env.je_buf, SCOPE_SAVES_SIGNAL_MASK);              \
112         OP_MEM_TO_REG;                                                  \
113         PL_top_env = &cur_env;                                          \
114         cur_env.je_mustcatch = FALSE;                                   \
115         (v) = cur_env.je_ret;                                           \
116     } STMT_END
117
118 #define JMPENV_POP \
119     STMT_START {                                                        \
120         DEBUG_l({                                                       \
121             int i = -1; JMPENV *p = PL_top_env;                         \
122             while (p) { i++; p = p->je_prev; }                          \
123             Perl_deb(aTHX_ "JUMPENV_POP level=%d at %s:%d\n",           \
124                          i, __FILE__, __LINE__);})                      \
125         assert(PL_top_env == &cur_env);                                 \
126         PL_top_env = cur_env.je_prev;                                   \
127     } STMT_END
128
129 #define JMPENV_JUMP(v) \
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_JUMP(%d) level=%d at %s:%d\n", \
135                          (int)v, i, __FILE__, __LINE__);})      \
136         OP_REG_TO_MEM;                                          \
137         if (PL_top_env->je_prev)                                \
138             PerlProc_longjmp(PL_top_env->je_buf, (v));          \
139         if ((v) == 2)                                           \
140             PerlProc_exit(STATUS_EXIT);                         \
141         PerlIO_printf(PerlIO_stderr(), "panic: top_env, v=%d\n", (int)v); \
142         PerlProc_exit(1);                                       \
143     } STMT_END
144
145 #define CATCH_GET               (PL_top_env->je_mustcatch)
146 #define CATCH_SET(v) \
147     STMT_START {                                                        \
148         DEBUG_l(                                                        \
149             Perl_deb(aTHX_                                              \
150                 "JUMPLEVEL set catch %d => %d (for %p) at %s:%d\n",     \
151                  PL_top_env->je_mustcatch, v, (void*)PL_top_env,        \
152                  __FILE__, __LINE__);)                                  \
153         PL_top_env->je_mustcatch = (v);                                 \
154     } STMT_END
155
156 /*
157 =head1 COP Hint Hashes
158 */
159
160 typedef struct refcounted_he COPHH;
161
162 #define COPHH_KEY_UTF8 REFCOUNTED_HE_KEY_UTF8
163
164 /*
165 =for apidoc Amx|SV *|cophh_fetch_pvn|const COPHH *cophh|const char *keypv|STRLEN keylen|U32 hash|U32 flags
166
167 Look up the entry in the cop hints hash I<cophh> with the key specified by
168 I<keypv> and I<keylen>.  If I<flags> has the C<COPHH_KEY_UTF8> bit set,
169 the key octets are interpreted as UTF-8, otherwise they are interpreted
170 as Latin-1.  I<hash> is a precomputed hash of the key string, or zero if
171 it has not been precomputed.  Returns a mortal scalar copy of the value
172 associated with the key, or C<&PL_sv_placeholder> if there is no value
173 associated with the key.
174
175 =cut
176 */
177
178 #define cophh_fetch_pvn(cophh, keypv, keylen, hash, flags) \
179     Perl_refcounted_he_fetch_pvn(aTHX_ cophh, keypv, keylen, hash, flags)
180
181 /*
182 =for apidoc Amx|SV *|cophh_fetch_pvs|const COPHH *cophh|const char *key|U32 flags
183
184 Like L</cophh_fetch_pvn>, but takes a literal string instead of a
185 string/length pair, and no precomputed hash.
186
187 =cut
188 */
189
190 #define cophh_fetch_pvs(cophh, key, flags) \
191     Perl_refcounted_he_fetch_pvn(aTHX_ cophh, STR_WITH_LEN(key), 0, flags)
192
193 /*
194 =for apidoc Amx|SV *|cophh_fetch_pv|const COPHH *cophh|const char *key|U32 hash|U32 flags
195
196 Like L</cophh_fetch_pvn>, but takes a nul-terminated string instead of
197 a string/length pair.
198
199 =cut
200 */
201
202 #define cophh_fetch_pv(cophh, key, hash, flags) \
203     Perl_refcounted_he_fetch_pv(aTHX_ cophh, key, hash, flags)
204
205 /*
206 =for apidoc Amx|SV *|cophh_fetch_sv|const COPHH *cophh|SV *key|U32 hash|U32 flags
207
208 Like L</cophh_fetch_pvn>, but takes a Perl scalar instead of a
209 string/length pair.
210
211 =cut
212 */
213
214 #define cophh_fetch_sv(cophh, key, hash, flags) \
215     Perl_refcounted_he_fetch_sv(aTHX_ cophh, key, hash, flags)
216
217 /*
218 =for apidoc Amx|HV *|cophh_2hv|const COPHH *cophh|U32 flags
219
220 Generates and returns a standard Perl hash representing the full set of
221 key/value pairs in the cop hints hash I<cophh>.  I<flags> is currently
222 unused and must be zero.
223
224 =cut
225 */
226
227 #define cophh_2hv(cophh, flags) \
228     Perl_refcounted_he_chain_2hv(aTHX_ cophh, flags)
229
230 /*
231 =for apidoc Amx|COPHH *|cophh_copy|COPHH *cophh
232
233 Make and return a complete copy of the cop hints hash I<cophh>.
234
235 =cut
236 */
237
238 #define cophh_copy(cophh) Perl_refcounted_he_inc(aTHX_ cophh)
239
240 /*
241 =for apidoc Amx|void|cophh_free|COPHH *cophh
242
243 Discard the cop hints hash I<cophh>, freeing all resources associated
244 with it.
245
246 =cut
247 */
248
249 #define cophh_free(cophh) Perl_refcounted_he_free(aTHX_ cophh)
250
251 /*
252 =for apidoc Amx|COPHH *|cophh_new_empty
253
254 Generate and return a fresh cop hints hash containing no entries.
255
256 =cut
257 */
258
259 #define cophh_new_empty() ((COPHH *)NULL)
260
261 /*
262 =for apidoc Amx|COPHH *|cophh_store_pvn|COPHH *cophh|const char *keypv|STRLEN keylen|U32 hash|SV *value|U32 flags
263
264 Stores a value, associated with a key, in the cop hints hash I<cophh>,
265 and returns the modified hash.  The returned hash pointer is in general
266 not the same as the hash pointer that was passed in.  The input hash is
267 consumed by the function, and the pointer to it must not be subsequently
268 used.  Use L</cophh_copy> if you need both hashes.
269
270 The key is specified by I<keypv> and I<keylen>.  If I<flags> has the
271 C<COPHH_KEY_UTF8> bit set, the key octets are interpreted as UTF-8,
272 otherwise they are interpreted as Latin-1.  I<hash> is a precomputed
273 hash of the key string, or zero if it has not been precomputed.
274
275 I<value> is the scalar value to store for this key.  I<value> is copied
276 by this function, which thus does not take ownership of any reference
277 to it, and later changes to the scalar will not be reflected in the
278 value visible in the cop hints hash.  Complex types of scalar will not
279 be stored with referential integrity, but will be coerced to strings.
280
281 =cut
282 */
283
284 #define cophh_store_pvn(cophh, keypv, keylen, hash, value, flags) \
285     Perl_refcounted_he_new_pvn(aTHX_ cophh, keypv, keylen, hash, value, flags)
286
287 /*
288 =for apidoc Amx|COPHH *|cophh_store_pvs|const COPHH *cophh|const char *key|SV *value|U32 flags
289
290 Like L</cophh_store_pvn>, but takes a literal string instead of a
291 string/length pair, and no precomputed hash.
292
293 =cut
294 */
295
296 #define cophh_store_pvs(cophh, key, value, flags) \
297     Perl_refcounted_he_new_pvn(aTHX_ cophh, STR_WITH_LEN(key), 0, value, flags)
298
299 /*
300 =for apidoc Amx|COPHH *|cophh_store_pv|const COPHH *cophh|const char *key|U32 hash|SV *value|U32 flags
301
302 Like L</cophh_store_pvn>, but takes a nul-terminated string instead of
303 a string/length pair.
304
305 =cut
306 */
307
308 #define cophh_store_pv(cophh, key, hash, value, flags) \
309     Perl_refcounted_he_new_pv(aTHX_ cophh, key, hash, value, flags)
310
311 /*
312 =for apidoc Amx|COPHH *|cophh_store_sv|const COPHH *cophh|SV *key|U32 hash|SV *value|U32 flags
313
314 Like L</cophh_store_pvn>, but takes a Perl scalar instead of a
315 string/length pair.
316
317 =cut
318 */
319
320 #define cophh_store_sv(cophh, key, hash, value, flags) \
321     Perl_refcounted_he_new_sv(aTHX_ cophh, key, hash, value, flags)
322
323 /*
324 =for apidoc Amx|COPHH *|cophh_delete_pvn|COPHH *cophh|const char *keypv|STRLEN keylen|U32 hash|U32 flags
325
326 Delete a key and its associated value from the cop hints hash I<cophh>,
327 and returns the modified hash.  The returned hash pointer is in general
328 not the same as the hash pointer that was passed in.  The input hash is
329 consumed by the function, and the pointer to it must not be subsequently
330 used.  Use L</cophh_copy> if you need both hashes.
331
332 The key is specified by I<keypv> and I<keylen>.  If I<flags> has the
333 C<COPHH_KEY_UTF8> bit set, the key octets are interpreted as UTF-8,
334 otherwise they are interpreted as Latin-1.  I<hash> is a precomputed
335 hash of the key string, or zero if it has not been precomputed.
336
337 =cut
338 */
339
340 #define cophh_delete_pvn(cophh, keypv, keylen, hash, flags) \
341     Perl_refcounted_he_new_pvn(aTHX_ cophh, keypv, keylen, hash, \
342         (SV *)NULL, flags)
343
344 /*
345 =for apidoc Amx|COPHH *|cophh_delete_pvs|const COPHH *cophh|const char *key|U32 flags
346
347 Like L</cophh_delete_pvn>, but takes a literal string instead of a
348 string/length pair, and no precomputed hash.
349
350 =cut
351 */
352
353 #define cophh_delete_pvs(cophh, key, flags) \
354     Perl_refcounted_he_new_pvn(aTHX_ cophh, STR_WITH_LEN(key), 0, \
355         (SV *)NULL, flags)
356
357 /*
358 =for apidoc Amx|COPHH *|cophh_delete_pv|const COPHH *cophh|const char *key|U32 hash|U32 flags
359
360 Like L</cophh_delete_pvn>, but takes a nul-terminated string instead of
361 a string/length pair.
362
363 =cut
364 */
365
366 #define cophh_delete_pv(cophh, key, hash, flags) \
367     Perl_refcounted_he_new_pv(aTHX_ cophh, key, hash, (SV *)NULL, flags)
368
369 /*
370 =for apidoc Amx|COPHH *|cophh_delete_sv|const COPHH *cophh|SV *key|U32 hash|U32 flags
371
372 Like L</cophh_delete_pvn>, but takes a Perl scalar instead of a
373 string/length pair.
374
375 =cut
376 */
377
378 #define cophh_delete_sv(cophh, key, hash, flags) \
379     Perl_refcounted_he_new_sv(aTHX_ cophh, key, hash, (SV *)NULL, flags)
380
381 #include "mydtrace.h"
382
383 struct cop {
384     BASEOP
385     /* On LP64 putting this here takes advantage of the fact that BASEOP isn't
386        an exact multiple of 8 bytes to save structure padding.  */
387     line_t      cop_line;       /* line # of this command */
388     /* label for this construct is now stored in cop_hints_hash */
389 #ifdef USE_ITHREADS
390     PADOFFSET   cop_stashoff;   /* offset into PL_stashpad, for the
391                                    package the line was compiled in */
392     char *      cop_file;       /* file name the following line # is from */
393 #else
394     HV *        cop_stash;      /* package line was compiled in */
395     GV *        cop_filegv;     /* file the following line # is from */
396 #endif
397     U32         cop_hints;      /* hints bits from pragmata */
398     U32         cop_seq;        /* parse sequence number */
399     /* Beware. mg.c and warnings.pl assume the type of this is STRLEN *:  */
400     STRLEN *    cop_warnings;   /* lexical warnings bitmask */
401     /* compile time state of %^H.  See the comment in op.c for how this is
402        used to recreate a hash to return from caller.  */
403     COPHH *     cop_hints_hash;
404 };
405
406 #ifdef USE_ITHREADS
407 #  define CopFILE(c)            ((c)->cop_file)
408 #  define CopFILEGV(c)          (CopFILE(c) \
409                                  ? gv_fetchfile(CopFILE(c)) : NULL)
410                                  
411 #  ifdef NETWARE
412 #    define CopFILE_set(c,pv)   ((c)->cop_file = savepv(pv))
413 #    define CopFILE_setn(c,pv,l)  ((c)->cop_file = savepv((pv),(l)))
414 #  else
415 #    define CopFILE_set(c,pv)   ((c)->cop_file = savesharedpv(pv))
416 #    define CopFILE_setn(c,pv,l)  ((c)->cop_file = savesharedpvn((pv),(l)))
417 #  endif
418
419 #  define CopFILESV(c)          (CopFILE(c) \
420                                  ? GvSV(gv_fetchfile(CopFILE(c))) : NULL)
421 #  define CopFILEAV(c)          (CopFILE(c) \
422                                  ? GvAV(gv_fetchfile(CopFILE(c))) : NULL)
423 #  define CopFILEAVx(c)         (assert_(CopFILE(c)) \
424                                    GvAV(gv_fetchfile(CopFILE(c))))
425
426 #  define CopSTASH(c)           PL_stashpad[(c)->cop_stashoff]
427 #  define CopSTASH_set(c,hv)    ((c)->cop_stashoff = (hv)               \
428                                     ? alloccopstash(hv)                 \
429                                     : 0)
430 #  ifdef NETWARE
431 #    define CopFILE_free(c) SAVECOPFILE_FREE(c)
432 #  else
433 #    define CopFILE_free(c)     (PerlMemShared_free(CopFILE(c)),(CopFILE(c) = NULL))
434 #  endif
435 #else
436 #  define CopFILEGV(c)          ((c)->cop_filegv)
437 #  define CopFILEGV_set(c,gv)   ((c)->cop_filegv = (GV*)SvREFCNT_inc(gv))
438 #  define CopFILE_set(c,pv)     CopFILEGV_set((c), gv_fetchfile(pv))
439 #  define CopFILE_setn(c,pv,l)  CopFILEGV_set((c), gv_fetchfile_flags((pv),(l),0))
440 #  define CopFILESV(c)          (CopFILEGV(c) ? GvSV(CopFILEGV(c)) : NULL)
441 #  define CopFILEAV(c)          (CopFILEGV(c) ? GvAV(CopFILEGV(c)) : NULL)
442 #  ifdef DEBUGGING
443 #    define CopFILEAVx(c)       (assert(CopFILEGV(c)), GvAV(CopFILEGV(c)))
444 #  else
445 #    define CopFILEAVx(c)       (GvAV(CopFILEGV(c)))
446 # endif
447 #  define CopFILE(c)            (CopFILEGV(c) && GvSV(CopFILEGV(c)) \
448                                     ? SvPVX(GvSV(CopFILEGV(c))) : NULL)
449 #  define CopSTASH(c)           ((c)->cop_stash)
450 #  define CopSTASH_set(c,hv)    ((c)->cop_stash = (hv))
451 #  define CopFILE_free(c)       (SvREFCNT_dec(CopFILEGV(c)),(CopFILEGV(c) = NULL))
452
453 #endif /* USE_ITHREADS */
454
455 #define CopSTASHPV(c)           (CopSTASH(c) ? HvNAME_get(CopSTASH(c)) : NULL)
456    /* cop_stash is not refcounted */
457 #define CopSTASHPV_set(c,pv)    CopSTASH_set((c), gv_stashpv(pv,GV_ADD))
458 #define CopSTASH_eq(c,hv)       (CopSTASH(c) == (hv))
459
460 #define CopHINTHASH_get(c)      ((COPHH*)((c)->cop_hints_hash))
461 #define CopHINTHASH_set(c,h)    ((c)->cop_hints_hash = (h))
462
463 /*
464 =head1 COP Hint Reading
465 */
466
467 /*
468 =for apidoc Am|SV *|cop_hints_fetch_pvn|const COP *cop|const char *keypv|STRLEN keylen|U32 hash|U32 flags
469
470 Look up the hint entry in the cop I<cop> with the key specified by
471 I<keypv> and I<keylen>.  If I<flags> has the C<COPHH_KEY_UTF8> bit set,
472 the key octets are interpreted as UTF-8, otherwise they are interpreted
473 as Latin-1.  I<hash> is a precomputed hash of the key string, or zero if
474 it has not been precomputed.  Returns a mortal scalar copy of the value
475 associated with the key, or C<&PL_sv_placeholder> if there is no value
476 associated with the key.
477
478 =cut
479 */
480
481 #define cop_hints_fetch_pvn(cop, keypv, keylen, hash, flags) \
482     cophh_fetch_pvn(CopHINTHASH_get(cop), keypv, keylen, hash, flags)
483
484 /*
485 =for apidoc Am|SV *|cop_hints_fetch_pvs|const COP *cop|const char *key|U32 flags
486
487 Like L</cop_hints_fetch_pvn>, but takes a literal string instead of a
488 string/length pair, and no precomputed hash.
489
490 =cut
491 */
492
493 #define cop_hints_fetch_pvs(cop, key, flags) \
494     cophh_fetch_pvs(CopHINTHASH_get(cop), key, flags)
495
496 /*
497 =for apidoc Am|SV *|cop_hints_fetch_pv|const COP *cop|const char *key|U32 hash|U32 flags
498
499 Like L</cop_hints_fetch_pvn>, but takes a nul-terminated string instead
500 of a string/length pair.
501
502 =cut
503 */
504
505 #define cop_hints_fetch_pv(cop, key, hash, flags) \
506     cophh_fetch_pv(CopHINTHASH_get(cop), key, hash, flags)
507
508 /*
509 =for apidoc Am|SV *|cop_hints_fetch_sv|const COP *cop|SV *key|U32 hash|U32 flags
510
511 Like L</cop_hints_fetch_pvn>, but takes a Perl scalar instead of a
512 string/length pair.
513
514 =cut
515 */
516
517 #define cop_hints_fetch_sv(cop, key, hash, flags) \
518     cophh_fetch_sv(CopHINTHASH_get(cop), key, hash, flags)
519
520 /*
521 =for apidoc Am|HV *|cop_hints_2hv|const COP *cop|U32 flags
522
523 Generates and returns a standard Perl hash representing the full set of
524 hint entries in the cop I<cop>.  I<flags> is currently unused and must
525 be zero.
526
527 =cut
528 */
529
530 #define cop_hints_2hv(cop, flags) \
531     cophh_2hv(CopHINTHASH_get(cop), flags)
532
533 #define CopLABEL(c)  Perl_cop_fetch_label(aTHX_ (c), NULL, NULL)
534 #define CopLABEL_len(c,len)  Perl_cop_fetch_label(aTHX_ (c), len, NULL)
535 #define CopLABEL_len_flags(c,len,flags)  Perl_cop_fetch_label(aTHX_ (c), len, flags)
536 #define CopLABEL_alloc(pv)      ((pv)?savepv(pv):NULL)
537
538 #define CopSTASH_ne(c,hv)       (!CopSTASH_eq(c,hv))
539 #define CopLINE(c)              ((c)->cop_line)
540 #define CopLINE_inc(c)          (++CopLINE(c))
541 #define CopLINE_dec(c)          (--CopLINE(c))
542 #define CopLINE_set(c,l)        (CopLINE(c) = (l))
543
544 /* OutCopFILE() is CopFILE for output (caller, die, warn, etc.) */
545 #define OutCopFILE(c) CopFILE(c)
546
547 #define CopHINTS_get(c)         ((c)->cop_hints + 0)
548 #define CopHINTS_set(c, h)      STMT_START {                            \
549                                     (c)->cop_hints = (h);               \
550                                 } STMT_END
551
552 /*
553  * Here we have some enormously heavy (or at least ponderous) wizardry.
554  */
555
556 /* subroutine context */
557 struct block_sub {
558     OP *        retop;  /* op to execute on exit from sub */
559     /* Above here is the same for sub, format and eval.  */
560     CV *        cv;
561     /* Above here is the same for sub and format.  */
562     AV *        savearray;
563     AV *        argarray;
564     I32         olddepth;
565     PAD         *oldcomppad;
566 };
567
568
569 /* format context */
570 struct block_format {
571     OP *        retop;  /* op to execute on exit from sub */
572     /* Above here is the same for sub, format and eval.  */
573     CV *        cv;
574     /* Above here is the same for sub and format.  */
575     GV *        gv;
576     GV *        dfoutgv;
577 };
578
579 /* base for the next two macros. Don't use directly.
580  * Note that the refcnt of the cv is incremented twice;  The CX one is
581  * decremented by LEAVESUB, the other by LEAVE. */
582
583 #define PUSHSUB_BASE(cx)                                                \
584         ENTRY_PROBE(CvNAMED(cv)                                         \
585                         ? HEK_KEY(CvNAME_HEK(cv))                       \
586                         : GvENAME(CvGV(cv)),                            \
587                 CopFILE((const COP *)CvSTART(cv)),                      \
588                 CopLINE((const COP *)CvSTART(cv)),                      \
589                 CopSTASHPV((const COP *)CvSTART(cv)));                  \
590                                                                         \
591         cx->blk_sub.cv = cv;                                            \
592         cx->blk_sub.olddepth = CvDEPTH(cv);                             \
593         cx->cx_type |= (hasargs) ? CXp_HASARGS : 0;                     \
594         cx->blk_sub.retop = NULL;                                       \
595         if (!CvDEPTH(cv)) {                                             \
596             SvREFCNT_inc_simple_void_NN(cv);                            \
597             SvREFCNT_inc_simple_void_NN(cv);                            \
598             SAVEFREESV(cv);                                             \
599         }
600
601 #define PUSHSUB_GET_LVALUE_MASK(func) \
602         /* If the context is indeterminate, then only the lvalue */     \
603         /* flags that the caller also has are applicable.        */     \
604         (                                                               \
605            (PL_op->op_flags & OPf_WANT)                                 \
606                ? OPpENTERSUB_LVAL_MASK                                  \
607                : !(PL_op->op_private & OPpENTERSUB_LVAL_MASK)           \
608                    ? 0 : (U8)func(aTHX)                                 \
609         )
610
611 #define PUSHSUB(cx)                                                     \
612     {                                                                   \
613         U8 phlags = PUSHSUB_GET_LVALUE_MASK(Perl_was_lvalue_sub);       \
614         PUSHSUB_BASE(cx)                                                \
615         cx->blk_u16 = PL_op->op_private &                               \
616                           (phlags|OPpDEREF);                            \
617     }
618
619 /* variant for use by OP_DBSTATE, where op_private holds hint bits */
620 #define PUSHSUB_DB(cx)                                                  \
621         PUSHSUB_BASE(cx)                                                \
622         cx->blk_u16 = 0;
623
624
625 #define PUSHFORMAT(cx, retop)                                           \
626         cx->blk_format.cv = cv;                                         \
627         cx->blk_format.gv = gv;                                         \
628         cx->blk_format.retop = (retop);                                 \
629         cx->blk_format.dfoutgv = PL_defoutgv;                           \
630         if (!CvDEPTH(cv)) SvREFCNT_inc_simple_void_NN(cv);              \
631         CvDEPTH(cv)++;                                                  \
632         SvREFCNT_inc_void(cx->blk_format.dfoutgv)
633
634 #define POP_SAVEARRAY()                                         \
635     STMT_START {                                                        \
636         SvREFCNT_dec(GvAV(PL_defgv));                                   \
637         GvAV(PL_defgv) = cx->blk_sub.savearray;                         \
638     } STMT_END
639
640 /* junk in @_ spells trouble when cloning CVs and in pp_caller(), so don't
641  * leave any (a fast av_clear(ary), basically) */
642 #define CLEAR_ARGARRAY(ary) \
643     STMT_START {                                                        \
644         AvMAX(ary) += AvARRAY(ary) - AvALLOC(ary);                      \
645         AvARRAY(ary) = AvALLOC(ary);                                    \
646         AvFILLp(ary) = -1;                                              \
647     } STMT_END
648
649 #define POPSUB(cx,sv)                                                   \
650     STMT_START {                                                        \
651         RETURN_PROBE(CvNAMED(cx->blk_sub.cv)                            \
652                         ? HEK_KEY(CvNAME_HEK(cx->blk_sub.cv))           \
653                         : GvENAME(CvGV(cx->blk_sub.cv)),                \
654                 CopFILE((COP*)CvSTART((const CV*)cx->blk_sub.cv)),      \
655                 CopLINE((COP*)CvSTART((const CV*)cx->blk_sub.cv)),      \
656                 CopSTASHPV((COP*)CvSTART((const CV*)cx->blk_sub.cv)));  \
657                                                                         \
658         if (CxHASARGS(cx)) {                                            \
659             POP_SAVEARRAY();                                            \
660             /* abandon @_ if it got reified */                          \
661             if (AvREAL(cx->blk_sub.argarray)) {                         \
662                 const SSize_t fill = AvFILLp(cx->blk_sub.argarray);     \
663                 SvREFCNT_dec_NN(cx->blk_sub.argarray);                  \
664                 cx->blk_sub.argarray = newAV();                         \
665                 av_extend(cx->blk_sub.argarray, fill);                  \
666                 AvREIFY_only(cx->blk_sub.argarray);                     \
667                 CX_CURPAD_SV(cx->blk_sub, 0) = MUTABLE_SV(cx->blk_sub.argarray); \
668             }                                                           \
669             else {                                                      \
670                 CLEAR_ARGARRAY(cx->blk_sub.argarray);                   \
671             }                                                           \
672         }                                                               \
673         sv = MUTABLE_SV(cx->blk_sub.cv);                                \
674         if (sv && (CvDEPTH((const CV*)sv) = cx->blk_sub.olddepth))      \
675             sv = NULL;                                          \
676     } STMT_END
677
678 #define LEAVESUB(sv)                                                    \
679     STMT_START {                                                        \
680         SvREFCNT_dec(sv);                                               \
681     } STMT_END
682
683 #define POPFORMAT(cx)                                                   \
684         setdefout(cx->blk_format.dfoutgv);                              \
685         CvDEPTH(cx->blk_format.cv)--;                                   \
686         if (!CvDEPTH(cx->blk_format.cv))                                \
687             SvREFCNT_dec_NN(cx->blk_format.cv);                         \
688         SvREFCNT_dec_NN(cx->blk_format.dfoutgv);
689
690 /* eval context */
691 struct block_eval {
692     OP *        retop;  /* op to execute on exit from eval */
693     /* Above here is the same for sub, format and eval.  */
694     SV *        old_namesv;
695     OP *        old_eval_root;
696     SV *        cur_text;
697     CV *        cv;
698     JMPENV *    cur_top_env; /* value of PL_top_env when eval CX created */
699 };
700
701 /* If we ever need more than 512 op types, change the shift from 7.
702    blku_gimme is actually also only 2 bits, so could be merged with something.
703 */
704
705 #define CxOLD_IN_EVAL(cx)       (((cx)->blk_u16) & 0x7F)
706 #define CxOLD_OP_TYPE(cx)       (((cx)->blk_u16) >> 7)
707
708 #define PUSHEVAL(cx,n)                                                  \
709     STMT_START {                                                        \
710         assert(!(PL_in_eval & ~0x7F));                                  \
711         assert(!(PL_op->op_type & ~0x1FF));                             \
712         cx->blk_u16 = (PL_in_eval & 0x7F) | ((U16)PL_op->op_type << 7); \
713         cx->blk_eval.old_namesv = (n ? newSVpv(n,0) : NULL);            \
714         cx->blk_eval.old_eval_root = PL_eval_root;                      \
715         cx->blk_eval.cur_text = PL_parser ? PL_parser->linestr : NULL;  \
716         cx->blk_eval.cv = NULL; /* set by doeval(), as applicable */    \
717         cx->blk_eval.retop = NULL;                                      \
718         cx->blk_eval.cur_top_env = PL_top_env;                          \
719     } STMT_END
720
721 #define POPEVAL(cx)                                                     \
722     STMT_START {                                                        \
723         PL_in_eval = CxOLD_IN_EVAL(cx);                                 \
724         optype = CxOLD_OP_TYPE(cx);                                     \
725         PL_eval_root = cx->blk_eval.old_eval_root;                      \
726         if (cx->blk_eval.cur_text && SvSCREAM(cx->blk_eval.cur_text))   \
727             SvREFCNT_dec_NN(cx->blk_eval.cur_text);                     \
728         if (cx->blk_eval.old_namesv)                                    \
729             sv_2mortal(cx->blk_eval.old_namesv);                        \
730     } STMT_END
731
732 /* loop context */
733 struct block_loop {
734     I32         resetsp;
735     LOOP *      my_op;  /* My op, that contains redo, next and last ops.  */
736     union {     /* different ways of locating the iteration variable */
737         SV      **svp;
738         GV      *gv;
739         PAD     *oldcomppad; /* only used in ITHREADS */
740     } itervar_u;
741     union {
742         struct { /* valid if type is LOOP_FOR or LOOP_PLAIN (but {NULL,0})*/
743             AV * ary; /* use the stack if this is NULL */
744             IV ix;
745         } ary;
746         struct { /* valid if type is LOOP_LAZYIV */
747             IV cur;
748             IV end;
749         } lazyiv;
750         struct { /* valid if type if LOOP_LAZYSV */
751             SV * cur;
752             SV * end; /* maxiumum value (or minimum in reverse) */
753         } lazysv;
754     } state_u;
755 };
756
757 #ifdef USE_ITHREADS
758 #  define CxITERVAR_PADSV(c) \
759         &CX_CURPAD_SV( (c)->blk_loop.itervar_u, (c)->blk_loop.my_op->op_targ)
760 #else
761 #  define CxITERVAR_PADSV(c) ((c)->blk_loop.itervar_u.svp)
762 #endif
763
764 #define CxITERVAR(c)                                                    \
765         ((c)->blk_loop.itervar_u.oldcomppad                             \
766          ? (CxPADLOOP(c)                                                \
767             ? CxITERVAR_PADSV(c)                                        \
768             : &GvSV((c)->blk_loop.itervar_u.gv))                        \
769          : (SV**)NULL)
770
771 #define CxLABEL(c)      (0 + CopLABEL((c)->blk_oldcop))
772 #define CxLABEL_len(c,len)      (0 + CopLABEL_len((c)->blk_oldcop, len))
773 #define CxLABEL_len_flags(c,len,flags)  (0 + CopLABEL_len_flags((c)->blk_oldcop, len, flags))
774 #define CxHASARGS(c)    (((c)->cx_type & CXp_HASARGS) == CXp_HASARGS)
775 #define CxLVAL(c)       (0 + (c)->blk_u16)
776
777 #define PUSHLOOP_PLAIN(cx, s)                                           \
778         cx->blk_loop.resetsp = s - PL_stack_base;                       \
779         cx->blk_loop.my_op = cLOOP;                                     \
780         cx->blk_loop.state_u.ary.ary = NULL;                            \
781         cx->blk_loop.state_u.ary.ix = 0;                                \
782         cx->blk_loop.itervar_u.svp = NULL;
783
784 #define PUSHLOOP_FOR(cx, ivar, s)                                       \
785         cx->blk_loop.resetsp = s - PL_stack_base;                       \
786         cx->blk_loop.my_op = cLOOP;                                     \
787         cx->blk_loop.state_u.ary.ary = NULL;                            \
788         cx->blk_loop.state_u.ary.ix = 0;                                \
789         cx->blk_loop.itervar_u.svp = (SV**)(ivar);
790
791 #define POPLOOP(cx)                                                     \
792         if (CxTYPE(cx) == CXt_LOOP_LAZYSV) {                            \
793             SvREFCNT_dec_NN(cx->blk_loop.state_u.lazysv.cur);           \
794             SvREFCNT_dec_NN(cx->blk_loop.state_u.lazysv.end);           \
795         }                                                               \
796         if (CxTYPE(cx) == CXt_LOOP_FOR)                                 \
797             SvREFCNT_dec(cx->blk_loop.state_u.ary.ary);
798
799 /* given/when context */
800 struct block_givwhen {
801         OP *leave_op;
802 };
803
804 #define PUSHGIVEN(cx)                                                   \
805         cx->blk_givwhen.leave_op = cLOGOP->op_other;
806
807 #define PUSHWHEN PUSHGIVEN
808
809 /* context common to subroutines, evals and loops */
810 struct block {
811     U8          blku_type;      /* what kind of context this is */
812     U8          blku_gimme;     /* is this block running in list context? */
813     U16         blku_u16;       /* used by block_sub and block_eval (so far) */
814     I32         blku_oldsp;     /* stack pointer to copy stuff down to */
815     COP *       blku_oldcop;    /* old curcop pointer */
816     I32         blku_oldmarksp; /* mark stack index */
817     I32         blku_oldscopesp;        /* scope stack index */
818     PMOP *      blku_oldpm;     /* values of pattern match vars */
819
820     union {
821         struct block_sub        blku_sub;
822         struct block_format     blku_format;
823         struct block_eval       blku_eval;
824         struct block_loop       blku_loop;
825         struct block_givwhen    blku_givwhen;
826     } blk_u;
827 };
828 #define blk_oldsp       cx_u.cx_blk.blku_oldsp
829 #define blk_oldcop      cx_u.cx_blk.blku_oldcop
830 #define blk_oldmarksp   cx_u.cx_blk.blku_oldmarksp
831 #define blk_oldscopesp  cx_u.cx_blk.blku_oldscopesp
832 #define blk_oldpm       cx_u.cx_blk.blku_oldpm
833 #define blk_gimme       cx_u.cx_blk.blku_gimme
834 #define blk_u16         cx_u.cx_blk.blku_u16
835 #define blk_sub         cx_u.cx_blk.blk_u.blku_sub
836 #define blk_format      cx_u.cx_blk.blk_u.blku_format
837 #define blk_eval        cx_u.cx_blk.blk_u.blku_eval
838 #define blk_loop        cx_u.cx_blk.blk_u.blku_loop
839 #define blk_givwhen     cx_u.cx_blk.blk_u.blku_givwhen
840
841 #define DEBUG_CX(action)                                                \
842     DEBUG_l(                                                            \
843         Perl_deb(aTHX_ "CX %ld %s %s (scope %ld,%ld) at %s:%d\n",       \
844                     (long)cxstack_ix,                                   \
845                     action,                                             \
846                     PL_block_type[CxTYPE(&cxstack[cxstack_ix])],        \
847                     (long)PL_scopestack_ix,                             \
848                     (long)(cxstack[cxstack_ix].blk_oldscopesp),         \
849                     __FILE__, __LINE__));
850
851 /* Enter a block. */
852 #define PUSHBLOCK(cx,t,sp) CXINC, cx = &cxstack[cxstack_ix],            \
853         cx->cx_type             = t,                                    \
854         cx->blk_oldsp           = sp - PL_stack_base,                   \
855         cx->blk_oldcop          = PL_curcop,                            \
856         cx->blk_oldmarksp       = PL_markstack_ptr - PL_markstack,      \
857         cx->blk_oldscopesp      = PL_scopestack_ix,                     \
858         cx->blk_oldpm           = PL_curpm,                             \
859         cx->blk_gimme           = (U8)gimme;                            \
860         DEBUG_CX("PUSH");
861
862 /* Exit a block (RETURN and LAST). */
863 #define POPBLOCK(cx,pm)                                                 \
864         DEBUG_CX("POP");                                                \
865         cx = &cxstack[cxstack_ix--],                                    \
866         newsp            = PL_stack_base + cx->blk_oldsp,               \
867         PL_curcop        = cx->blk_oldcop,                              \
868         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
869         PL_scopestack_ix = cx->blk_oldscopesp,                          \
870         pm               = cx->blk_oldpm,                               \
871         gimme            = cx->blk_gimme;
872
873 /* Continue a block elsewhere (NEXT and REDO). */
874 #define TOPBLOCK(cx)                                                    \
875         DEBUG_CX("TOP");                                                \
876         cx  = &cxstack[cxstack_ix],                                     \
877         PL_stack_sp      = PL_stack_base + cx->blk_oldsp,               \
878         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
879         PL_scopestack_ix = cx->blk_oldscopesp,                          \
880         PL_curpm         = cx->blk_oldpm;
881
882 /* substitution context */
883 struct subst {
884     U8          sbu_type;       /* what kind of context this is */
885     U8          sbu_rflags;
886     U16         sbu_rxtainted;  /* matches struct block */
887     I32         sbu_iters;
888     I32         sbu_maxiters;
889     I32         sbu_oldsave;
890     char *      sbu_orig;
891     SV *        sbu_dstr;
892     SV *        sbu_targ;
893     char *      sbu_s;
894     char *      sbu_m;
895     char *      sbu_strend;
896     void *      sbu_rxres;
897     REGEXP *    sbu_rx;
898 };
899 #define sb_iters        cx_u.cx_subst.sbu_iters
900 #define sb_maxiters     cx_u.cx_subst.sbu_maxiters
901 #define sb_rflags       cx_u.cx_subst.sbu_rflags
902 #define sb_oldsave      cx_u.cx_subst.sbu_oldsave
903 #define sb_rxtainted    cx_u.cx_subst.sbu_rxtainted
904 #define sb_orig         cx_u.cx_subst.sbu_orig
905 #define sb_dstr         cx_u.cx_subst.sbu_dstr
906 #define sb_targ         cx_u.cx_subst.sbu_targ
907 #define sb_s            cx_u.cx_subst.sbu_s
908 #define sb_m            cx_u.cx_subst.sbu_m
909 #define sb_strend       cx_u.cx_subst.sbu_strend
910 #define sb_rxres        cx_u.cx_subst.sbu_rxres
911 #define sb_rx           cx_u.cx_subst.sbu_rx
912
913 #ifdef PERL_CORE
914 #  define PUSHSUBST(cx) CXINC, cx = &cxstack[cxstack_ix],               \
915         cx->sb_iters            = iters,                                \
916         cx->sb_maxiters         = maxiters,                             \
917         cx->sb_rflags           = r_flags,                              \
918         cx->sb_oldsave          = oldsave,                              \
919         cx->sb_rxtainted        = rxtainted,                            \
920         cx->sb_orig             = orig,                                 \
921         cx->sb_dstr             = dstr,                                 \
922         cx->sb_targ             = targ,                                 \
923         cx->sb_s                = s,                                    \
924         cx->sb_m                = m,                                    \
925         cx->sb_strend           = strend,                               \
926         cx->sb_rxres            = NULL,                                 \
927         cx->sb_rx               = rx,                                   \
928         cx->cx_type             = CXt_SUBST | (once ? CXp_ONCE : 0);    \
929         rxres_save(&cx->sb_rxres, rx);                                  \
930         (void)ReREFCNT_inc(rx)
931
932 #  define POPSUBST(cx) cx = &cxstack[cxstack_ix--];                     \
933         rxres_free(&cx->sb_rxres);                                      \
934         ReREFCNT_dec(cx->sb_rx)
935 #endif
936
937 #define CxONCE(cx)              ((cx)->cx_type & CXp_ONCE)
938
939 struct context {
940     union {
941         struct block    cx_blk;
942         struct subst    cx_subst;
943     } cx_u;
944 };
945 #define cx_type cx_u.cx_subst.sbu_type
946
947 /* If you re-order these, there is also an array of uppercase names in perl.h
948    and a static array of context names in pp_ctl.c  */
949 #define CXTYPEMASK      0xf
950 #define CXt_NULL        0
951 #define CXt_WHEN        1
952 #define CXt_BLOCK       2
953 /* When micro-optimising :-) keep GIVEN next to the LOOPs, as these 5 share a
954    jump table in pp_ctl.c
955    The first 4 don't have a 'case' in at least one switch statement in pp_ctl.c
956 */
957 #define CXt_GIVEN       3
958 /* This is first so that CXt_LOOP_FOR|CXt_LOOP_LAZYIV is CXt_LOOP_LAZYIV */
959 #define CXt_LOOP_FOR    4
960 #define CXt_LOOP_PLAIN  5
961 #define CXt_LOOP_LAZYSV 6
962 #define CXt_LOOP_LAZYIV 7
963 #define CXt_SUB         8
964 #define CXt_FORMAT      9
965 #define CXt_EVAL       10
966 #define CXt_SUBST      11
967 /* SUBST doesn't feature in all switch statements.  */
968
969 /* private flags for CXt_SUB and CXt_NULL
970    However, this is checked in many places which do not check the type, so
971    this bit needs to be kept clear for most everything else. For reasons I
972    haven't investigated, it can coexist with CXp_FOR_DEF */
973 #define CXp_MULTICALL   0x10    /* part of a multicall (so don't
974                                    tear down context on exit). */ 
975
976 /* private flags for CXt_SUB and CXt_FORMAT */
977 #define CXp_HASARGS     0x20
978 #define CXp_SUB_RE      0x40    /* code called within regex, i.e. (?{}) */
979 #define CXp_SUB_RE_FAKE 0x80    /* fake sub CX for (?{}) in current scope */
980
981 /* private flags for CXt_EVAL */
982 #define CXp_REAL        0x20    /* truly eval'', not a lookalike */
983 #define CXp_TRYBLOCK    0x40    /* eval{}, not eval'' or similar */
984
985 /* private flags for CXt_LOOP */
986 #define CXp_FOR_DEF     0x10    /* foreach using $_ */
987 #define CxPADLOOP(c)    ((c)->blk_loop.my_op->op_targ)
988
989 /* private flags for CXt_SUBST */
990 #define CXp_ONCE        0x10    /* What was sbu_once in struct subst */
991
992 #define CxTYPE(c)       ((c)->cx_type & CXTYPEMASK)
993 #define CxTYPE_is_LOOP(c)       (((c)->cx_type & 0xC) == 0x4)
994 #define CxMULTICALL(c)  (((c)->cx_type & CXp_MULTICALL)                 \
995                          == CXp_MULTICALL)
996 #define CxREALEVAL(c)   (((c)->cx_type & (CXTYPEMASK|CXp_REAL))         \
997                          == (CXt_EVAL|CXp_REAL))
998 #define CxTRYBLOCK(c)   (((c)->cx_type & (CXTYPEMASK|CXp_TRYBLOCK))     \
999                          == (CXt_EVAL|CXp_TRYBLOCK))
1000 #define CxFOREACH(c)    (CxTYPE_is_LOOP(c) && CxTYPE(c) != CXt_LOOP_PLAIN)
1001 #define CxFOREACHDEF(c) ((CxTYPE_is_LOOP(c) && CxTYPE(c) != CXt_LOOP_PLAIN) \
1002                          && ((c)->cx_type & CXp_FOR_DEF))
1003
1004 #define CXINC (cxstack_ix < cxstack_max ? ++cxstack_ix : (cxstack_ix = cxinc()))
1005
1006 /* 
1007 =head1 "Gimme" Values
1008 */
1009
1010 /*
1011 =for apidoc AmU||G_SCALAR
1012 Used to indicate scalar context.  See C<GIMME_V>, C<GIMME>, and
1013 L<perlcall>.
1014
1015 =for apidoc AmU||G_ARRAY
1016 Used to indicate list context.  See C<GIMME_V>, C<GIMME> and
1017 L<perlcall>.
1018
1019 =for apidoc AmU||G_VOID
1020 Used to indicate void context.  See C<GIMME_V> and L<perlcall>.
1021
1022 =for apidoc AmU||G_DISCARD
1023 Indicates that arguments returned from a callback should be discarded.  See
1024 L<perlcall>.
1025
1026 =for apidoc AmU||G_EVAL
1027
1028 Used to force a Perl C<eval> wrapper around a callback.  See
1029 L<perlcall>.
1030
1031 =for apidoc AmU||G_NOARGS
1032
1033 Indicates that no arguments are being sent to a callback.  See
1034 L<perlcall>.
1035
1036 =cut
1037 */
1038
1039 #define G_SCALAR        2
1040 #define G_ARRAY         3
1041 #define G_VOID          1
1042 #define G_WANT          3
1043
1044 /* extra flags for Perl_call_* routines */
1045 #define G_DISCARD       4       /* Call FREETMPS.
1046                                    Don't change this without consulting the
1047                                    hash actions codes defined in hv.h */
1048 #define G_EVAL          8       /* Assume eval {} around subroutine call. */
1049 #define G_NOARGS       16       /* Don't construct a @_ array. */
1050 #define G_KEEPERR      32       /* Warn for errors, don't overwrite $@ */
1051 #define G_NODEBUG      64       /* Disable debugging at toplevel.  */
1052 #define G_METHOD      128       /* Calling method. */
1053 #define G_FAKINGEVAL  256       /* Faking an eval context for call_sv or
1054                                    fold_constants. */
1055 #define G_UNDEF_FILL  512       /* Fill the stack with &PL_sv_undef
1056                                    A special case for UNSHIFT in
1057                                    Perl_magic_methcall().  */
1058 #define G_WRITING_TO_STDERR 1024 /* Perl_write_to_stderr() is calling
1059                                     Perl_magic_methcall().  */
1060 #define G_RE_REPARSING 0x800     /* compiling a run-time /(?{..})/ */
1061 #define G_METHOD_NAMED 4096     /* calling named method, eg without :: or ' */
1062
1063 /* flag bits for PL_in_eval */
1064 #define EVAL_NULL       0       /* not in an eval */
1065 #define EVAL_INEVAL     1       /* some enclosing scope is an eval */
1066 #define EVAL_WARNONLY   2       /* used by yywarn() when calling yyerror() */
1067 #define EVAL_KEEPERR    4       /* set by Perl_call_sv if G_KEEPERR */
1068 #define EVAL_INREQUIRE  8       /* The code is being required. */
1069 #define EVAL_RE_REPARSING 0x10  /* eval_sv() called with G_RE_REPARSING */
1070
1071 /* Support for switching (stack and block) contexts.
1072  * This ensures magic doesn't invalidate local stack and cx pointers.
1073  */
1074
1075 #define PERLSI_UNKNOWN          -1
1076 #define PERLSI_UNDEF            0
1077 #define PERLSI_MAIN             1
1078 #define PERLSI_MAGIC            2
1079 #define PERLSI_SORT             3
1080 #define PERLSI_SIGNAL           4
1081 #define PERLSI_OVERLOAD         5
1082 #define PERLSI_DESTROY          6
1083 #define PERLSI_WARNHOOK         7
1084 #define PERLSI_DIEHOOK          8
1085 #define PERLSI_REQUIRE          9
1086
1087 struct stackinfo {
1088     AV *                si_stack;       /* stack for current runlevel */
1089     PERL_CONTEXT *      si_cxstack;     /* context stack for runlevel */
1090     struct stackinfo *  si_prev;
1091     struct stackinfo *  si_next;
1092     I32                 si_cxix;        /* current context index */
1093     I32                 si_cxmax;       /* maximum allocated index */
1094     I32                 si_type;        /* type of runlevel */
1095     I32                 si_markoff;     /* offset where markstack begins for us.
1096                                          * currently used only with DEBUGGING,
1097                                          * but not #ifdef-ed for bincompat */
1098 };
1099
1100 typedef struct stackinfo PERL_SI;
1101
1102 #define cxstack         (PL_curstackinfo->si_cxstack)
1103 #define cxstack_ix      (PL_curstackinfo->si_cxix)
1104 #define cxstack_max     (PL_curstackinfo->si_cxmax)
1105
1106 #ifdef DEBUGGING
1107 #  define       SET_MARK_OFFSET \
1108     PL_curstackinfo->si_markoff = PL_markstack_ptr - PL_markstack
1109 #else
1110 #  define       SET_MARK_OFFSET NOOP
1111 #endif
1112
1113 #define PUSHSTACKi(type) \
1114     STMT_START {                                                        \
1115         PERL_SI *next = PL_curstackinfo->si_next;                       \
1116         DEBUG_l({                                                       \
1117             int i = 0; PERL_SI *p = PL_curstackinfo;                    \
1118             while (p) { i++; p = p->si_prev; }                          \
1119             Perl_deb(aTHX_ "push STACKINFO %d at %s:%d\n",              \
1120                          i, __FILE__, __LINE__);})                      \
1121         if (!next) {                                                    \
1122             next = new_stackinfo(32, 2048/sizeof(PERL_CONTEXT) - 1);    \
1123             next->si_prev = PL_curstackinfo;                            \
1124             PL_curstackinfo->si_next = next;                            \
1125         }                                                               \
1126         next->si_type = type;                                           \
1127         next->si_cxix = -1;                                             \
1128         AvFILLp(next->si_stack) = 0;                                    \
1129         SWITCHSTACK(PL_curstack,next->si_stack);                        \
1130         PL_curstackinfo = next;                                         \
1131         SET_MARK_OFFSET;                                                \
1132     } STMT_END
1133
1134 #define PUSHSTACK PUSHSTACKi(PERLSI_UNKNOWN)
1135
1136 /* POPSTACK works with PL_stack_sp, so it may need to be bracketed by
1137  * PUTBACK/SPAGAIN to flush/refresh any local SP that may be active */
1138 #define POPSTACK \
1139     STMT_START {                                                        \
1140         dSP;                                                            \
1141         PERL_SI * const prev = PL_curstackinfo->si_prev;                \
1142         DEBUG_l({                                                       \
1143             int i = -1; PERL_SI *p = PL_curstackinfo;                   \
1144             while (p) { i++; p = p->si_prev; }                          \
1145             Perl_deb(aTHX_ "pop  STACKINFO %d at %s:%d\n",              \
1146                          i, __FILE__, __LINE__);})                      \
1147         if (!prev) {                                                    \
1148             Perl_croak_popstack();                                      \
1149         }                                                               \
1150         SWITCHSTACK(PL_curstack,prev->si_stack);                        \
1151         /* don't free prev here, free them all at the END{} */          \
1152         PL_curstackinfo = prev;                                         \
1153     } STMT_END
1154
1155 #define POPSTACK_TO(s) \
1156     STMT_START {                                                        \
1157         while (PL_curstack != s) {                                      \
1158             dounwind(-1);                                               \
1159             POPSTACK;                                                   \
1160         }                                                               \
1161     } STMT_END
1162
1163 #define IN_PERL_COMPILETIME     (PL_curcop == &PL_compiling)
1164 #define IN_PERL_RUNTIME         (PL_curcop != &PL_compiling)
1165
1166 /*
1167 =head1 Multicall Functions
1168
1169 =for apidoc Ams||dMULTICALL
1170 Declare local variables for a multicall. See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1171
1172 =for apidoc Ams||PUSH_MULTICALL
1173 Opening bracket for a lightweight callback.
1174 See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1175
1176 =for apidoc Ams||MULTICALL
1177 Make a lightweight callback. See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1178
1179 =for apidoc Ams||POP_MULTICALL
1180 Closing bracket for a lightweight callback.
1181 See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1182
1183 =cut
1184 */
1185
1186 #define dMULTICALL \
1187     SV **newsp;                 /* set by POPBLOCK */                   \
1188     PERL_CONTEXT *cx;                                                   \
1189     CV *multicall_cv;                                                   \
1190     OP *multicall_cop;                                                  \
1191     bool multicall_oldcatch;                                            \
1192     U8 hasargs = 0              /* used by PUSHSUB */
1193
1194 #define PUSH_MULTICALL(the_cv) \
1195     PUSH_MULTICALL_FLAGS(the_cv, 0)
1196
1197 /* Like PUSH_MULTICALL, but allows you to specify extra flags
1198  * for the CX stack entry (this isn't part of the public API) */
1199
1200 #define PUSH_MULTICALL_FLAGS(the_cv, flags) \
1201     STMT_START {                                                        \
1202         CV * const _nOnclAshIngNamE_ = the_cv;                          \
1203         CV * const cv = _nOnclAshIngNamE_;                              \
1204         PADLIST * const padlist = CvPADLIST(cv);                        \
1205         ENTER;                                                          \
1206         multicall_oldcatch = CATCH_GET;                                 \
1207         SAVETMPS; SAVEVPTR(PL_op);                                      \
1208         CATCH_SET(TRUE);                                                \
1209         PUSHSTACKi(PERLSI_SORT);                                        \
1210         PUSHBLOCK(cx, (CXt_SUB|CXp_MULTICALL|flags), PL_stack_sp);      \
1211         PUSHSUB(cx);                                                    \
1212         if (!(flags & CXp_SUB_RE_FAKE))                                 \
1213             CvDEPTH(cv)++;                                              \
1214         if (CvDEPTH(cv) >= 2) {                                         \
1215             PERL_STACK_OVERFLOW_CHECK();                                \
1216             Perl_pad_push(aTHX_ padlist, CvDEPTH(cv));                  \
1217         }                                                               \
1218         SAVECOMPPAD();                                                  \
1219         PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));                       \
1220         multicall_cv = cv;                                              \
1221         multicall_cop = CvSTART(cv);                                    \
1222     } STMT_END
1223
1224 #define MULTICALL \
1225     STMT_START {                                                        \
1226         PL_op = multicall_cop;                                          \
1227         CALLRUNOPS(aTHX);                                               \
1228     } STMT_END
1229
1230 #define POP_MULTICALL \
1231     STMT_START {                                                        \
1232         cx = &cxstack[cxstack_ix];                                      \
1233         if (! ((CvDEPTH(multicall_cv) = cx->blk_sub.olddepth)) ) {      \
1234                 LEAVESUB(multicall_cv);                                 \
1235         }                                                               \
1236         POPBLOCK(cx,PL_curpm);                                          \
1237         POPSTACK;                                                       \
1238         CATCH_SET(multicall_oldcatch);                                  \
1239         LEAVE;                                                          \
1240         SPAGAIN;                                                        \
1241     } STMT_END
1242
1243 /* Change the CV of an already-pushed MULTICALL CxSUB block.
1244  * (this isn't part of the public API) */
1245
1246 #define CHANGE_MULTICALL_FLAGS(the_cv, flags) \
1247     STMT_START {                                                        \
1248         CV * const _nOnclAshIngNamE_ = the_cv;                          \
1249         CV * const cv = _nOnclAshIngNamE_;                              \
1250         PADLIST * const padlist = CvPADLIST(cv);                        \
1251         cx = &cxstack[cxstack_ix];                                      \
1252         assert(cx->cx_type & CXp_MULTICALL);                            \
1253         if (! ((CvDEPTH(multicall_cv) = cx->blk_sub.olddepth)) ) {      \
1254                 LEAVESUB(multicall_cv);                                 \
1255         }                                                               \
1256         cx->cx_type = (CXt_SUB|CXp_MULTICALL|flags);                    \
1257         PUSHSUB(cx);                                                    \
1258         if (!(flags & CXp_SUB_RE_FAKE))                                 \
1259             CvDEPTH(cv)++;                                              \
1260         if (CvDEPTH(cv) >= 2) {                                         \
1261             PERL_STACK_OVERFLOW_CHECK();                                \
1262             Perl_pad_push(aTHX_ padlist, CvDEPTH(cv));                  \
1263         }                                                               \
1264         SAVECOMPPAD();                                                  \
1265         PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));                       \
1266         multicall_cv = cv;                                              \
1267         multicall_cop = CvSTART(cv);                                    \
1268     } STMT_END
1269 /*
1270  * Local variables:
1271  * c-indentation-style: bsd
1272  * c-basic-offset: 4
1273  * indent-tabs-mode: nil
1274  * End:
1275  *
1276  * ex: set ts=8 sts=4 sw=4 et:
1277  */