This is a live mirror of the Perl 5 development currently hosted at https://github.com/perl/perl5
3a643c314db0d2974f6a2ec4906220e2ae3d3208
[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 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 };
39
40 typedef struct jmpenv JMPENV;
41
42 /*
43  * How to build the first jmpenv.
44  *
45  * top_env needs to be non-zero. It points to an area
46  * in which longjmp() stuff is stored, as C callstack
47  * info there at least is thread specific this has to
48  * be per-thread. Otherwise a 'die' in a thread gives
49  * that thread the C stack of last thread to do an eval {}!
50  */
51
52 #define JMPENV_BOOTSTRAP \
53     STMT_START {                                \
54         PERL_POISON_EXPR(PoisonNew(&PL_start_env, 1, JMPENV));\
55         PL_top_env = &PL_start_env;             \
56         PL_start_env.je_prev = NULL;            \
57         PL_start_env.je_ret = -1;               \
58         PL_start_env.je_mustcatch = TRUE;       \
59         PL_start_env.je_old_delaymagic = 0;     \
60     } STMT_END
61
62 /*
63  *   PERL_FLEXIBLE_EXCEPTIONS
64  * 
65  * All the flexible exceptions code has been removed.
66  * See the following threads for details:
67  *
68  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/2004-07/msg00378.html
69  * 
70  * Joshua's original patches (which weren't applied) and discussion:
71  * 
72  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01396.html
73  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01489.html
74  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01491.html
75  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01608.html
76  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg02144.html
77  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg02998.html
78  * 
79  * Chip's reworked patch and discussion:
80  * 
81  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1999-03/msg00520.html
82  * 
83  * The flaw in these patches (which went unnoticed at the time) was
84  * that they moved some code that could potentially die() out of the
85  * region protected by the setjmp()s.  This caused exceptions within
86  * END blocks and such to not be handled by the correct setjmp().
87  * 
88  * The original patches that introduces flexible exceptions were:
89  *
90  * http://perl5.git.perl.org/perl.git/commit/312caa8e97f1c7ee342a9895c2f0e749625b4929
91  * http://perl5.git.perl.org/perl.git/commit/14dd3ad8c9bf82cf09798a22cc89a9862dfd6d1a                                        
92  *  
93  */
94
95 #define dJMPENV         JMPENV cur_env
96
97 #define JMPENV_PUSH(v) \
98     STMT_START {                                                        \
99         DEBUG_l({                                                       \
100             int i = 0; JMPENV *p = PL_top_env;                          \
101             while (p) { i++; p = p->je_prev; }                          \
102             Perl_deb(aTHX_ "JUMPENV_PUSH level=%d at %s:%d\n",          \
103                          i,  __FILE__, __LINE__);})                     \
104         cur_env.je_prev = PL_top_env;                                   \
105         cur_env.je_ret = PerlProc_setjmp(cur_env.je_buf, SCOPE_SAVES_SIGNAL_MASK);              \
106         PL_top_env = &cur_env;                                          \
107         cur_env.je_mustcatch = FALSE;                                   \
108         cur_env.je_old_delaymagic = PL_delaymagic;                      \
109         (v) = cur_env.je_ret;                                           \
110     } STMT_END
111
112 #define JMPENV_POP \
113     STMT_START {                                                        \
114         DEBUG_l({                                                       \
115             int i = -1; JMPENV *p = PL_top_env;                         \
116             while (p) { i++; p = p->je_prev; }                          \
117             Perl_deb(aTHX_ "JUMPENV_POP level=%d at %s:%d\n",           \
118                          i, __FILE__, __LINE__);})                      \
119         assert(PL_top_env == &cur_env);                                 \
120         PL_delaymagic = cur_env.je_old_delaymagic;                      \
121         PL_top_env = cur_env.je_prev;                                   \
122     } STMT_END
123
124 #define JMPENV_JUMP(v) \
125     STMT_START {                                                \
126         DEBUG_l({                                               \
127             int i = -1; JMPENV *p = PL_top_env;                 \
128             while (p) { i++; p = p->je_prev; }                  \
129             Perl_deb(aTHX_ "JUMPENV_JUMP(%d) level=%d at %s:%d\n", \
130                          (int)v, i, __FILE__, __LINE__);})      \
131         if (PL_top_env->je_prev)                                \
132             PerlProc_longjmp(PL_top_env->je_buf, (v));          \
133         if ((v) == 2)                                           \
134             PerlProc_exit(STATUS_EXIT);                         \
135         PerlIO_printf(PerlIO_stderr(), "panic: top_env, v=%d\n", (int)v); \
136         PerlProc_exit(1);                                       \
137     } STMT_END
138
139 #define CATCH_GET               (PL_top_env->je_mustcatch)
140 #define CATCH_SET(v) \
141     STMT_START {                                                        \
142         DEBUG_l(                                                        \
143             Perl_deb(aTHX_                                              \
144                 "JUMPLEVEL set catch %d => %d (for %p) at %s:%d\n",     \
145                  PL_top_env->je_mustcatch, v, (void*)PL_top_env,        \
146                  __FILE__, __LINE__);)                                  \
147         PL_top_env->je_mustcatch = (v);                                 \
148     } STMT_END
149
150 /*
151 =head1 COP Hint Hashes
152 */
153
154 typedef struct refcounted_he COPHH;
155
156 #define COPHH_KEY_UTF8 REFCOUNTED_HE_KEY_UTF8
157
158 /*
159 =for apidoc Amx|SV *|cophh_fetch_pvn|const COPHH *cophh|const char *keypv|STRLEN keylen|U32 hash|U32 flags
160
161 Look up the entry in the cop hints hash C<cophh> with the key specified by
162 C<keypv> and C<keylen>.  If C<flags> has the C<COPHH_KEY_UTF8> bit set,
163 the key octets are interpreted as UTF-8, otherwise they are interpreted
164 as Latin-1.  C<hash> is a precomputed hash of the key string, or zero if
165 it has not been precomputed.  Returns a mortal scalar copy of the value
166 associated with the key, or C<&PL_sv_placeholder> if there is no value
167 associated with the key.
168
169 =cut
170 */
171
172 #define cophh_fetch_pvn(cophh, keypv, keylen, hash, flags) \
173     Perl_refcounted_he_fetch_pvn(aTHX_ cophh, keypv, keylen, hash, flags)
174
175 /*
176 =for apidoc Amx|SV *|cophh_fetch_pvs|const COPHH *cophh|const char *key|U32 flags
177
178 Like L</cophh_fetch_pvn>, but takes a literal string instead of a
179 string/length pair, and no precomputed hash.
180
181 =cut
182 */
183
184 #define cophh_fetch_pvs(cophh, key, flags) \
185     Perl_refcounted_he_fetch_pvn(aTHX_ cophh, STR_WITH_LEN(key), 0, flags)
186
187 /*
188 =for apidoc Amx|SV *|cophh_fetch_pv|const COPHH *cophh|const char *key|U32 hash|U32 flags
189
190 Like L</cophh_fetch_pvn>, but takes a nul-terminated string instead of
191 a string/length pair.
192
193 =cut
194 */
195
196 #define cophh_fetch_pv(cophh, key, hash, flags) \
197     Perl_refcounted_he_fetch_pv(aTHX_ cophh, key, hash, flags)
198
199 /*
200 =for apidoc Amx|SV *|cophh_fetch_sv|const COPHH *cophh|SV *key|U32 hash|U32 flags
201
202 Like L</cophh_fetch_pvn>, but takes a Perl scalar instead of a
203 string/length pair.
204
205 =cut
206 */
207
208 #define cophh_fetch_sv(cophh, key, hash, flags) \
209     Perl_refcounted_he_fetch_sv(aTHX_ cophh, key, hash, flags)
210
211 /*
212 =for apidoc Amx|HV *|cophh_2hv|const COPHH *cophh|U32 flags
213
214 Generates and returns a standard Perl hash representing the full set of
215 key/value pairs in the cop hints hash C<cophh>.  C<flags> is currently
216 unused and must be zero.
217
218 =cut
219 */
220
221 #define cophh_2hv(cophh, flags) \
222     Perl_refcounted_he_chain_2hv(aTHX_ cophh, flags)
223
224 /*
225 =for apidoc Amx|COPHH *|cophh_copy|COPHH *cophh
226
227 Make and return a complete copy of the cop hints hash C<cophh>.
228
229 =cut
230 */
231
232 #define cophh_copy(cophh) Perl_refcounted_he_inc(aTHX_ cophh)
233
234 /*
235 =for apidoc Amx|void|cophh_free|COPHH *cophh
236
237 Discard the cop hints hash C<cophh>, freeing all resources associated
238 with it.
239
240 =cut
241 */
242
243 #define cophh_free(cophh) Perl_refcounted_he_free(aTHX_ cophh)
244
245 /*
246 =for apidoc Amx|COPHH *|cophh_new_empty
247
248 Generate and return a fresh cop hints hash containing no entries.
249
250 =cut
251 */
252
253 #define cophh_new_empty() ((COPHH *)NULL)
254
255 /*
256 =for apidoc Amx|COPHH *|cophh_store_pvn|COPHH *cophh|const char *keypv|STRLEN keylen|U32 hash|SV *value|U32 flags
257
258 Stores a value, associated with a key, in the cop hints hash C<cophh>,
259 and returns the modified hash.  The returned hash pointer is in general
260 not the same as the hash pointer that was passed in.  The input hash is
261 consumed by the function, and the pointer to it must not be subsequently
262 used.  Use L</cophh_copy> if you need both hashes.
263
264 The key is specified by C<keypv> and C<keylen>.  If C<flags> has the
265 C<COPHH_KEY_UTF8> bit set, the key octets are interpreted as UTF-8,
266 otherwise they are interpreted as Latin-1.  C<hash> is a precomputed
267 hash of the key string, or zero if it has not been precomputed.
268
269 C<value> is the scalar value to store for this key.  C<value> is copied
270 by this function, which thus does not take ownership of any reference
271 to it, and later changes to the scalar will not be reflected in the
272 value visible in the cop hints hash.  Complex types of scalar will not
273 be stored with referential integrity, but will be coerced to strings.
274
275 =cut
276 */
277
278 #define cophh_store_pvn(cophh, keypv, keylen, hash, value, flags) \
279     Perl_refcounted_he_new_pvn(aTHX_ cophh, keypv, keylen, hash, value, flags)
280
281 /*
282 =for apidoc Amx|COPHH *|cophh_store_pvs|const COPHH *cophh|const char *key|SV *value|U32 flags
283
284 Like L</cophh_store_pvn>, but takes a literal string instead of a
285 string/length pair, and no precomputed hash.
286
287 =cut
288 */
289
290 #define cophh_store_pvs(cophh, key, value, flags) \
291     Perl_refcounted_he_new_pvn(aTHX_ cophh, STR_WITH_LEN(key), 0, value, flags)
292
293 /*
294 =for apidoc Amx|COPHH *|cophh_store_pv|const COPHH *cophh|const char *key|U32 hash|SV *value|U32 flags
295
296 Like L</cophh_store_pvn>, but takes a nul-terminated string instead of
297 a string/length pair.
298
299 =cut
300 */
301
302 #define cophh_store_pv(cophh, key, hash, value, flags) \
303     Perl_refcounted_he_new_pv(aTHX_ cophh, key, hash, value, flags)
304
305 /*
306 =for apidoc Amx|COPHH *|cophh_store_sv|const COPHH *cophh|SV *key|U32 hash|SV *value|U32 flags
307
308 Like L</cophh_store_pvn>, but takes a Perl scalar instead of a
309 string/length pair.
310
311 =cut
312 */
313
314 #define cophh_store_sv(cophh, key, hash, value, flags) \
315     Perl_refcounted_he_new_sv(aTHX_ cophh, key, hash, value, flags)
316
317 /*
318 =for apidoc Amx|COPHH *|cophh_delete_pvn|COPHH *cophh|const char *keypv|STRLEN keylen|U32 hash|U32 flags
319
320 Delete a key and its associated value from the cop hints hash C<cophh>,
321 and returns the modified hash.  The returned hash pointer is in general
322 not the same as the hash pointer that was passed in.  The input hash is
323 consumed by the function, and the pointer to it must not be subsequently
324 used.  Use L</cophh_copy> if you need both hashes.
325
326 The key is specified by C<keypv> and C<keylen>.  If C<flags> has the
327 C<COPHH_KEY_UTF8> bit set, the key octets are interpreted as UTF-8,
328 otherwise they are interpreted as Latin-1.  C<hash> is a precomputed
329 hash of the key string, or zero if it has not been precomputed.
330
331 =cut
332 */
333
334 #define cophh_delete_pvn(cophh, keypv, keylen, hash, flags) \
335     Perl_refcounted_he_new_pvn(aTHX_ cophh, keypv, keylen, hash, \
336         (SV *)NULL, flags)
337
338 /*
339 =for apidoc Amx|COPHH *|cophh_delete_pvs|const COPHH *cophh|const char *key|U32 flags
340
341 Like L</cophh_delete_pvn>, but takes a literal string instead of a
342 string/length pair, and no precomputed hash.
343
344 =cut
345 */
346
347 #define cophh_delete_pvs(cophh, key, flags) \
348     Perl_refcounted_he_new_pvn(aTHX_ cophh, STR_WITH_LEN(key), 0, \
349         (SV *)NULL, flags)
350
351 /*
352 =for apidoc Amx|COPHH *|cophh_delete_pv|const COPHH *cophh|const char *key|U32 hash|U32 flags
353
354 Like L</cophh_delete_pvn>, but takes a nul-terminated string instead of
355 a string/length pair.
356
357 =cut
358 */
359
360 #define cophh_delete_pv(cophh, key, hash, flags) \
361     Perl_refcounted_he_new_pv(aTHX_ cophh, key, hash, (SV *)NULL, flags)
362
363 /*
364 =for apidoc Amx|COPHH *|cophh_delete_sv|const COPHH *cophh|SV *key|U32 hash|U32 flags
365
366 Like L</cophh_delete_pvn>, but takes a Perl scalar instead of a
367 string/length pair.
368
369 =cut
370 */
371
372 #define cophh_delete_sv(cophh, key, hash, flags) \
373     Perl_refcounted_he_new_sv(aTHX_ cophh, key, hash, (SV *)NULL, flags)
374
375 #include "mydtrace.h"
376
377 struct cop {
378     BASEOP
379     /* On LP64 putting this here takes advantage of the fact that BASEOP isn't
380        an exact multiple of 8 bytes to save structure padding.  */
381     line_t      cop_line;       /* line # of this command */
382     /* label for this construct is now stored in cop_hints_hash */
383 #ifdef USE_ITHREADS
384     PADOFFSET   cop_stashoff;   /* offset into PL_stashpad, for the
385                                    package the line was compiled in */
386     char *      cop_file;       /* file name the following line # is from */
387 #else
388     HV *        cop_stash;      /* package line was compiled in */
389     GV *        cop_filegv;     /* file the following line # is from */
390 #endif
391     U32         cop_hints;      /* hints bits from pragmata */
392     U32         cop_seq;        /* parse sequence number */
393     /* Beware. mg.c and warnings.pl assume the type of this is STRLEN *:  */
394     STRLEN *    cop_warnings;   /* lexical warnings bitmask */
395     /* compile time state of %^H.  See the comment in op.c for how this is
396        used to recreate a hash to return from caller.  */
397     COPHH *     cop_hints_hash;
398 };
399
400 #ifdef USE_ITHREADS
401 #  define CopFILE(c)            ((c)->cop_file)
402 #  define CopFILEGV(c)          (CopFILE(c) \
403                                  ? gv_fetchfile(CopFILE(c)) : NULL)
404                                  
405 #  ifdef NETWARE
406 #    define CopFILE_set(c,pv)   ((c)->cop_file = savepv(pv))
407 #    define CopFILE_setn(c,pv,l)  ((c)->cop_file = savepvn((pv),(l)))
408 #  else
409 #    define CopFILE_set(c,pv)   ((c)->cop_file = savesharedpv(pv))
410 #    define CopFILE_setn(c,pv,l)  ((c)->cop_file = savesharedpvn((pv),(l)))
411 #  endif
412
413 #  define CopFILESV(c)          (CopFILE(c) \
414                                  ? GvSV(gv_fetchfile(CopFILE(c))) : NULL)
415 #  define CopFILEAV(c)          (CopFILE(c) \
416                                  ? GvAV(gv_fetchfile(CopFILE(c))) : NULL)
417 #  define CopFILEAVx(c)         (assert_(CopFILE(c)) \
418                                    GvAV(gv_fetchfile(CopFILE(c))))
419
420 #  define CopSTASH(c)           PL_stashpad[(c)->cop_stashoff]
421 #  define CopSTASH_set(c,hv)    ((c)->cop_stashoff = (hv)               \
422                                     ? alloccopstash(hv)                 \
423                                     : 0)
424 #  ifdef NETWARE
425 #    define CopFILE_free(c) SAVECOPFILE_FREE(c)
426 #  else
427 #    define CopFILE_free(c)     (PerlMemShared_free(CopFILE(c)),(CopFILE(c) = NULL))
428 #  endif
429 #else
430 #  define CopFILEGV(c)          ((c)->cop_filegv)
431 #  define CopFILEGV_set(c,gv)   ((c)->cop_filegv = (GV*)SvREFCNT_inc(gv))
432 #  define CopFILE_set(c,pv)     CopFILEGV_set((c), gv_fetchfile(pv))
433 #  define CopFILE_setn(c,pv,l)  CopFILEGV_set((c), gv_fetchfile_flags((pv),(l),0))
434 #  define CopFILESV(c)          (CopFILEGV(c) ? GvSV(CopFILEGV(c)) : NULL)
435 #  define CopFILEAV(c)          (CopFILEGV(c) ? GvAV(CopFILEGV(c)) : NULL)
436 #  ifdef DEBUGGING
437 #    define CopFILEAVx(c)       (assert(CopFILEGV(c)), GvAV(CopFILEGV(c)))
438 #  else
439 #    define CopFILEAVx(c)       (GvAV(CopFILEGV(c)))
440 # endif
441 #  define CopFILE(c)            (CopFILEGV(c) \
442                                     ? GvNAME(CopFILEGV(c))+2 : NULL)
443 #  define CopSTASH(c)           ((c)->cop_stash)
444 #  define CopSTASH_set(c,hv)    ((c)->cop_stash = (hv))
445 #  define CopFILE_free(c)       (SvREFCNT_dec(CopFILEGV(c)),(CopFILEGV(c) = NULL))
446
447 #endif /* USE_ITHREADS */
448
449 #define CopSTASHPV(c)           (CopSTASH(c) ? HvNAME_get(CopSTASH(c)) : NULL)
450    /* cop_stash is not refcounted */
451 #define CopSTASHPV_set(c,pv)    CopSTASH_set((c), gv_stashpv(pv,GV_ADD))
452 #define CopSTASH_eq(c,hv)       (CopSTASH(c) == (hv))
453
454 #define CopHINTHASH_get(c)      ((COPHH*)((c)->cop_hints_hash))
455 #define CopHINTHASH_set(c,h)    ((c)->cop_hints_hash = (h))
456
457 /*
458 =head1 COP Hint Reading
459 */
460
461 /*
462 =for apidoc Am|SV *|cop_hints_fetch_pvn|const COP *cop|const char *keypv|STRLEN keylen|U32 hash|U32 flags
463
464 Look up the hint entry in the cop C<cop> with the key specified by
465 C<keypv> and C<keylen>.  If C<flags> has the C<COPHH_KEY_UTF8> bit set,
466 the key octets are interpreted as UTF-8, otherwise they are interpreted
467 as Latin-1.  C<hash> is a precomputed hash of the key string, or zero if
468 it has not been precomputed.  Returns a mortal scalar copy of the value
469 associated with the key, or C<&PL_sv_placeholder> if there is no value
470 associated with the key.
471
472 =cut
473 */
474
475 #define cop_hints_fetch_pvn(cop, keypv, keylen, hash, flags) \
476     cophh_fetch_pvn(CopHINTHASH_get(cop), keypv, keylen, hash, flags)
477
478 /*
479 =for apidoc Am|SV *|cop_hints_fetch_pvs|const COP *cop|const char *key|U32 flags
480
481 Like L</cop_hints_fetch_pvn>, but takes a literal string instead of a
482 string/length pair, and no precomputed hash.
483
484 =cut
485 */
486
487 #define cop_hints_fetch_pvs(cop, key, flags) \
488     cophh_fetch_pvs(CopHINTHASH_get(cop), key, flags)
489
490 /*
491 =for apidoc Am|SV *|cop_hints_fetch_pv|const COP *cop|const char *key|U32 hash|U32 flags
492
493 Like L</cop_hints_fetch_pvn>, but takes a nul-terminated string instead
494 of a string/length pair.
495
496 =cut
497 */
498
499 #define cop_hints_fetch_pv(cop, key, hash, flags) \
500     cophh_fetch_pv(CopHINTHASH_get(cop), key, hash, flags)
501
502 /*
503 =for apidoc Am|SV *|cop_hints_fetch_sv|const COP *cop|SV *key|U32 hash|U32 flags
504
505 Like L</cop_hints_fetch_pvn>, but takes a Perl scalar instead of a
506 string/length pair.
507
508 =cut
509 */
510
511 #define cop_hints_fetch_sv(cop, key, hash, flags) \
512     cophh_fetch_sv(CopHINTHASH_get(cop), key, hash, flags)
513
514 /*
515 =for apidoc Am|HV *|cop_hints_2hv|const COP *cop|U32 flags
516
517 Generates and returns a standard Perl hash representing the full set of
518 hint entries in the cop C<cop>.  C<flags> is currently unused and must
519 be zero.
520
521 =cut
522 */
523
524 #define cop_hints_2hv(cop, flags) \
525     cophh_2hv(CopHINTHASH_get(cop), flags)
526
527 #define CopLABEL(c)  Perl_cop_fetch_label(aTHX_ (c), NULL, NULL)
528 #define CopLABEL_len(c,len)  Perl_cop_fetch_label(aTHX_ (c), len, NULL)
529 #define CopLABEL_len_flags(c,len,flags)  Perl_cop_fetch_label(aTHX_ (c), len, flags)
530 #define CopLABEL_alloc(pv)      ((pv)?savepv(pv):NULL)
531
532 #define CopSTASH_ne(c,hv)       (!CopSTASH_eq(c,hv))
533 #define CopLINE(c)              ((c)->cop_line)
534 #define CopLINE_inc(c)          (++CopLINE(c))
535 #define CopLINE_dec(c)          (--CopLINE(c))
536 #define CopLINE_set(c,l)        (CopLINE(c) = (l))
537
538 /* OutCopFILE() is CopFILE for output (caller, die, warn, etc.) */
539 #define OutCopFILE(c) CopFILE(c)
540
541 #define CopHINTS_get(c)         ((c)->cop_hints + 0)
542 #define CopHINTS_set(c, h)      STMT_START {                            \
543                                     (c)->cop_hints = (h);               \
544                                 } STMT_END
545
546 /*
547  * Here we have some enormously heavy (or at least ponderous) wizardry.
548  */
549
550 /* subroutine context */
551 struct block_sub {
552     OP *        retop;  /* op to execute on exit from sub */
553     /* Above here is the same for sub, format and eval.  */
554     CV *        cv;
555     /* Above here is the same for sub and format.  */
556     AV *        savearray;
557     I32         olddepth;
558     PAD         *prevcomppad; /* the caller's PL_comppad */
559     SSize_t     old_tmpsfloor; /* also used in CXt_NULL sort block */
560 };
561
562
563 /* format context */
564 struct block_format {
565     OP *        retop;  /* op to execute on exit from sub */
566     /* Above here is the same for sub, format and eval.  */
567     CV *        cv;
568     /* Above here is the same for sub and format.  */
569     GV *        gv;
570     GV *        dfoutgv;
571     PAD         *prevcomppad; /* the caller's PL_comppad */
572 };
573
574 /* base for the next two macros. Don't use directly.
575  * The context frame holds a reference to the CV so that it can't be
576  * freed while we're executing it */
577
578 #define PUSHSUB_BASE(cx)                                                \
579         ENTRY_PROBE(CvNAMED(cv)                                         \
580                         ? HEK_KEY(CvNAME_HEK(cv))                       \
581                         : GvENAME(CvGV(cv)),                            \
582                 CopFILE((const COP *)CvSTART(cv)),                      \
583                 CopLINE((const COP *)CvSTART(cv)),                      \
584                 CopSTASHPV((const COP *)CvSTART(cv)));                  \
585                                                                         \
586         cx->blk_sub.cv = cv;                                            \
587         cx->blk_sub.olddepth = CvDEPTH(cv);                             \
588         cx->blk_sub.prevcomppad = PL_comppad;                           \
589         cx->cx_type |= (hasargs) ? CXp_HASARGS : 0;                     \
590         cx->blk_sub.retop = NULL;                                       \
591         SvREFCNT_inc_simple_void_NN(cv);                                \
592         cx->blk_sub.old_tmpsfloor = PL_tmps_floor;                      \
593         PL_tmps_floor = PL_tmps_ix;
594
595 #define PUSHSUB_GET_LVALUE_MASK(func) \
596         /* If the context is indeterminate, then only the lvalue */     \
597         /* flags that the caller also has are applicable.        */     \
598         (                                                               \
599            (PL_op->op_flags & OPf_WANT)                                 \
600                ? OPpENTERSUB_LVAL_MASK                                  \
601                : !(PL_op->op_private & OPpENTERSUB_LVAL_MASK)           \
602                    ? 0 : (U8)func(aTHX)                                 \
603         )
604
605 #define PUSHSUB(cx)                                                     \
606     {                                                                   \
607         U8 phlags = PUSHSUB_GET_LVALUE_MASK(Perl_was_lvalue_sub);       \
608         PUSHSUB_BASE(cx)                                                \
609         cx->blk_u16 = PL_op->op_private &                               \
610                           (phlags|OPpDEREF);                            \
611     }
612
613 /* variant for use by OP_DBSTATE, where op_private holds hint bits */
614 #define PUSHSUB_DB(cx)                                                  \
615         PUSHSUB_BASE(cx)                                                \
616         cx->blk_u16 = 0;
617
618
619 #define PUSHFORMAT(cx, retop)                                           \
620         cx->blk_format.cv = cv;                                         \
621         cx->blk_format.gv = gv;                                         \
622         cx->blk_format.retop = (retop);                                 \
623         cx->blk_format.dfoutgv = PL_defoutgv;                           \
624         cx->blk_format.prevcomppad = PL_comppad;                        \
625         cx->blk_u16 = 0;                                                \
626         SvREFCNT_inc_simple_void_NN(cv);                                \
627         CvDEPTH(cv)++;                                                  \
628         SvREFCNT_inc_void(cx->blk_format.dfoutgv)
629
630 /* Restore old @_ */
631 #define POP_SAVEARRAY()                                         \
632     STMT_START {                                                        \
633         AV *av = GvAV(PL_defgv);                                        \
634         GvAV(PL_defgv) = cx->blk_sub.savearray;                         \
635         SvREFCNT_dec(av);                                               \
636     } STMT_END
637
638 /* junk in @_ spells trouble when cloning CVs and in pp_caller(), so don't
639  * leave any (a fast av_clear(ary), basically) */
640 #define CLEAR_ARGARRAY(ary) \
641     STMT_START {                                                        \
642         AvMAX(ary) += AvARRAY(ary) - AvALLOC(ary);                      \
643         AvARRAY(ary) = AvALLOC(ary);                                    \
644         AvFILLp(ary) = -1;                                              \
645     } STMT_END
646
647 #define POPSUB(cx,sv)                                                   \
648     STMT_START {                                                        \
649         const I32 olddepth = cx->blk_sub.olddepth;                      \
650         if (!(cx->blk_u16 & CxPOPSUB_DONE)) {                           \
651         cx->blk_u16 |= CxPOPSUB_DONE;                                   \
652         RETURN_PROBE(CvNAMED(cx->blk_sub.cv)                            \
653                         ? HEK_KEY(CvNAME_HEK(cx->blk_sub.cv))           \
654                         : GvENAME(CvGV(cx->blk_sub.cv)),                \
655                 CopFILE((COP*)CvSTART((const CV*)cx->blk_sub.cv)),      \
656                 CopLINE((COP*)CvSTART((const CV*)cx->blk_sub.cv)),      \
657                 CopSTASHPV((COP*)CvSTART((const CV*)cx->blk_sub.cv)));  \
658                                                                         \
659         if (CxHASARGS(cx)) {                                            \
660             AV *av = MUTABLE_AV(PAD_SVl(0));                            \
661             assert(AvARRAY(MUTABLE_AV(                                  \
662                 PadlistARRAY(CvPADLIST(cx->blk_sub.cv))[                \
663                         CvDEPTH(cx->blk_sub.cv)])) == PL_curpad);       \
664             POP_SAVEARRAY();                                            \
665             /* abandon @_ if it got reified */                          \
666             if (UNLIKELY(AvREAL(av)))                                   \
667                 clear_defarray(av, 0);                                  \
668             else {                                                      \
669                 CLEAR_ARGARRAY(av);                                     \
670             }                                                           \
671         }                                                               \
672         }                                                               \
673         sv = MUTABLE_SV(cx->blk_sub.cv);                                \
674         LEAVE_SCOPE(PL_scopestack[cx->blk_oldscopesp-1]);               \
675         PL_tmps_floor = cx->blk_sub.old_tmpsfloor;                      \
676         PL_comppad = cx->blk_sub.prevcomppad;                           \
677         PL_curpad = LIKELY(PL_comppad) ? AvARRAY(PL_comppad) : NULL;    \
678         CvDEPTH((const CV*)sv) = olddepth;                              \
679     } STMT_END
680
681 #define LEAVESUB(sv)                                                    \
682     STMT_START {                                                        \
683         SvREFCNT_dec(sv);                                               \
684     } STMT_END
685
686 #define POPFORMAT(cx)                                                   \
687     STMT_START {                                                        \
688         if (!(cx->blk_u16 & CxPOPSUB_DONE)) {                           \
689         CV * const cv = cx->blk_format.cv;                              \
690         GV * const dfuot = cx->blk_format.dfoutgv;                      \
691         cx->blk_u16 |= CxPOPSUB_DONE;                                   \
692         setdefout(dfuot);                                               \
693         LEAVE_SCOPE(PL_scopestack[cx->blk_oldscopesp-1]);               \
694         PL_comppad = cx->blk_format.prevcomppad;                        \
695         PL_curpad = LIKELY(PL_comppad) ? AvARRAY(PL_comppad) : NULL;    \
696         --CvDEPTH(cv);                                                  \
697         SvREFCNT_dec_NN(cx->blk_format.cv);                             \
698         SvREFCNT_dec_NN(dfuot);                                         \
699         }                                                               \
700     } STMT_END
701
702 /* eval context */
703 struct block_eval {
704     OP *        retop;  /* op to execute on exit from eval */
705     /* Above here is the same for sub, format and eval.  */
706     SV *        old_namesv;
707     OP *        old_eval_root;
708     SV *        cur_text;
709     CV *        cv;
710     JMPENV *    cur_top_env; /* value of PL_top_env when eval CX created */
711 };
712
713 /* If we ever need more than 512 op types, change the shift from 7.
714    blku_gimme is actually also only 2 bits, so could be merged with something.
715 */
716
717 #define CxOLD_IN_EVAL(cx)       (((cx)->blk_u16) & 0x7F)
718 #define CxOLD_OP_TYPE(cx)       (((cx)->blk_u16) >> 7)
719
720 #define PUSHEVAL(cx,n)                                                  \
721     STMT_START {                                                        \
722         assert(!(PL_in_eval & ~0x7F));                                  \
723         assert(!(PL_op->op_type & ~0x1FF));                             \
724         cx->blk_u16 = (PL_in_eval & 0x7F) | ((U16)PL_op->op_type << 7); \
725         cx->blk_eval.old_namesv = (n ? newSVpv(n,0) : NULL);            \
726         cx->blk_eval.old_eval_root = PL_eval_root;                      \
727         cx->blk_eval.cur_text = PL_parser ? PL_parser->linestr : NULL;  \
728         cx->blk_eval.cv = NULL; /* set by doeval(), as applicable */    \
729         cx->blk_eval.retop = NULL;                                      \
730         cx->blk_eval.cur_top_env = PL_top_env;                          \
731     } STMT_END
732
733 #define POPEVAL(cx)                                                     \
734     STMT_START {                                                        \
735         PL_in_eval = CxOLD_IN_EVAL(cx);                                 \
736         optype = CxOLD_OP_TYPE(cx);                                     \
737         PL_eval_root = cx->blk_eval.old_eval_root;                      \
738         if (cx->blk_eval.cur_text && SvSCREAM(cx->blk_eval.cur_text))   \
739             SvREFCNT_dec_NN(cx->blk_eval.cur_text);                     \
740         if (cx->blk_eval.old_namesv)                                    \
741             sv_2mortal(cx->blk_eval.old_namesv);                        \
742     } STMT_END
743
744 /* loop context */
745 struct block_loop {
746     I32         resetsp;
747     LOOP *      my_op;  /* My op, that contains redo, next and last ops.  */
748     union {     /* different ways of locating the iteration variable */
749         SV      **svp; /* for lexicals: address of pad slot */
750         GV      *gv;   /* for package vars */
751     } itervar_u;
752     union {
753         struct { /* valid if type is LOOP_FOR or LOOP_PLAIN (but {NULL,0})*/
754             AV * ary; /* use the stack if this is NULL */
755             IV ix;
756         } ary;
757         struct { /* valid if type is LOOP_LAZYIV */
758             IV cur;
759             IV end;
760         } lazyiv;
761         struct { /* valid if type if LOOP_LAZYSV */
762             SV * cur;
763             SV * end; /* maxiumum value (or minimum in reverse) */
764         } lazysv;
765     } state_u;
766 #ifdef USE_ITHREADS
767     PAD *oldcomppad; /* needed to map itervar_u.svp during thread clone */
768 #endif
769 };
770
771 #define CxITERVAR(c)                                                    \
772         (CxPADLOOP(c)                                                   \
773             ? (c)->blk_loop.itervar_u.svp                               \
774             : (c)->blk_loop.itervar_u.svp                               \
775                 ? isGV((c)->blk_loop.itervar_u.gv)                      \
776                     ? &GvSV((c)->blk_loop.itervar_u.gv)                 \
777                     : (SV **)&(c)->blk_loop.itervar_u.gv                \
778                 : (SV**)NULL)
779
780 #define CxLABEL(c)      (0 + CopLABEL((c)->blk_oldcop))
781 #define CxLABEL_len(c,len)      (0 + CopLABEL_len((c)->blk_oldcop, len))
782 #define CxLABEL_len_flags(c,len,flags)  (0 + CopLABEL_len_flags((c)->blk_oldcop, len, flags))
783 #define CxHASARGS(c)    (((c)->cx_type & CXp_HASARGS) == CXp_HASARGS)
784 #define CxLVAL(c)       (0 + ((c)->blk_u16 & 0xff))
785 /* POPSUB has already been performed on this context frame */
786 #define CxPOPSUB_DONE 0x100
787
788
789 #define PUSHLOOP_PLAIN(cx, s)                                           \
790         cx->blk_loop.resetsp = s - PL_stack_base;                       \
791         cx->blk_loop.my_op = cLOOP;                                     \
792         cx->blk_loop.state_u.ary.ary = NULL;                            \
793         cx->blk_loop.state_u.ary.ix = 0;                                \
794         cx->blk_loop.itervar_u.svp = NULL;
795
796 #ifdef USE_ITHREADS
797 #  define PUSHLOOP_FOR_setpad(c) (c)->blk_loop.oldcomppad = PL_comppad
798 #else
799 #  define PUSHLOOP_FOR_setpad(c) NOOP
800 #endif
801
802 #define PUSHLOOP_FOR(cx, ivar, s)                                       \
803         cx->blk_loop.resetsp = s - PL_stack_base;                       \
804         cx->blk_loop.my_op = cLOOP;                                     \
805         cx->blk_loop.state_u.ary.ary = NULL;                            \
806         cx->blk_loop.state_u.ary.ix = 0;                                \
807         cx->blk_loop.itervar_u.svp = (SV**)(ivar);                      \
808         PUSHLOOP_FOR_setpad(cx);
809
810 #define POPLOOP(cx)                                                     \
811         if (CxTYPE(cx) == CXt_LOOP_LAZYSV) {                            \
812             SvREFCNT_dec_NN(cx->blk_loop.state_u.lazysv.cur);           \
813             SvREFCNT_dec_NN(cx->blk_loop.state_u.lazysv.end);           \
814         }                                                               \
815         if (CxTYPE(cx) == CXt_LOOP_FOR)                                 \
816             SvREFCNT_dec(cx->blk_loop.state_u.ary.ary);
817
818 /* given/when context */
819 struct block_givwhen {
820         OP *leave_op;
821 };
822
823 #define PUSHGIVEN(cx)                                                   \
824         cx->blk_givwhen.leave_op = cLOGOP->op_other;
825
826 #define PUSHWHEN PUSHGIVEN
827
828 /* context common to subroutines, evals and loops */
829 struct block {
830     U8          blku_type;      /* what kind of context this is */
831     U8          blku_gimme;     /* is this block running in list context? */
832     U16         blku_u16;       /* used by block_sub and block_eval (so far) */
833     I32         blku_oldsp;     /* stack pointer to copy stuff down to */
834     COP *       blku_oldcop;    /* old curcop pointer */
835     I32         blku_oldmarksp; /* mark stack index */
836     I32         blku_oldscopesp;        /* scope stack index */
837     PMOP *      blku_oldpm;     /* values of pattern match vars */
838
839     union {
840         struct block_sub        blku_sub;
841         struct block_format     blku_format;
842         struct block_eval       blku_eval;
843         struct block_loop       blku_loop;
844         struct block_givwhen    blku_givwhen;
845     } blk_u;
846 };
847 #define blk_oldsp       cx_u.cx_blk.blku_oldsp
848 #define blk_oldcop      cx_u.cx_blk.blku_oldcop
849 #define blk_oldmarksp   cx_u.cx_blk.blku_oldmarksp
850 #define blk_oldscopesp  cx_u.cx_blk.blku_oldscopesp
851 #define blk_oldpm       cx_u.cx_blk.blku_oldpm
852 #define blk_gimme       cx_u.cx_blk.blku_gimme
853 #define blk_u16         cx_u.cx_blk.blku_u16
854 #define blk_sub         cx_u.cx_blk.blk_u.blku_sub
855 #define blk_format      cx_u.cx_blk.blk_u.blku_format
856 #define blk_eval        cx_u.cx_blk.blk_u.blku_eval
857 #define blk_loop        cx_u.cx_blk.blk_u.blku_loop
858 #define blk_givwhen     cx_u.cx_blk.blk_u.blku_givwhen
859
860 #define DEBUG_CX(action)                                                \
861     DEBUG_l(                                                            \
862         Perl_deb(aTHX_ "CX %ld %s %s (scope %ld,%ld) at %s:%d\n",       \
863                     (long)cxstack_ix,                                   \
864                     action,                                             \
865                     PL_block_type[CxTYPE(&cxstack[cxstack_ix])],        \
866                     (long)PL_scopestack_ix,                             \
867                     (long)(cxstack[cxstack_ix].blk_oldscopesp),         \
868                     __FILE__, __LINE__));
869
870 /* Enter a block. */
871 #define PUSHBLOCK(cx,t,sp) CXINC, cx = &cxstack[cxstack_ix],            \
872         cx->cx_type             = t,                                    \
873         cx->blk_oldsp           = sp - PL_stack_base,                   \
874         cx->blk_oldcop          = PL_curcop,                            \
875         cx->blk_oldmarksp       = PL_markstack_ptr - PL_markstack,      \
876         cx->blk_oldscopesp      = PL_scopestack_ix,                     \
877         cx->blk_oldpm           = PL_curpm,                             \
878         cx->blk_gimme           = (U8)gimme;                            \
879         DEBUG_CX("PUSH");
880
881 /* Exit a block (RETURN and LAST). */
882 #define POPBLOCK(cx,pm)                                                 \
883         DEBUG_CX("POP");                                                \
884         cx = &cxstack[cxstack_ix--],                                    \
885         newsp            = PL_stack_base + cx->blk_oldsp,               \
886         PL_curcop        = cx->blk_oldcop,                              \
887         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
888         PL_scopestack_ix = cx->blk_oldscopesp,                          \
889         pm               = cx->blk_oldpm,                               \
890         gimme            = cx->blk_gimme;
891
892 /* Continue a block elsewhere (NEXT and REDO). */
893 #define TOPBLOCK(cx)                                                    \
894         DEBUG_CX("TOP");                                                \
895         cx  = &cxstack[cxstack_ix],                                     \
896         PL_stack_sp      = PL_stack_base + cx->blk_oldsp,               \
897         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
898         PL_scopestack_ix = cx->blk_oldscopesp,                          \
899         PL_curpm         = cx->blk_oldpm;
900
901 /* substitution context */
902 struct subst {
903     U8          sbu_type;       /* what kind of context this is */
904     U8          sbu_rflags;
905     U16         sbu_rxtainted;  /* matches struct block */
906     I32         sbu_oldsave;
907     SSize_t     sbu_iters;
908     SSize_t     sbu_maxiters;
909     char *      sbu_orig;
910     SV *        sbu_dstr;
911     SV *        sbu_targ;
912     char *      sbu_s;
913     char *      sbu_m;
914     char *      sbu_strend;
915     void *      sbu_rxres;
916     REGEXP *    sbu_rx;
917 };
918 #define sb_iters        cx_u.cx_subst.sbu_iters
919 #define sb_maxiters     cx_u.cx_subst.sbu_maxiters
920 #define sb_rflags       cx_u.cx_subst.sbu_rflags
921 #define sb_oldsave      cx_u.cx_subst.sbu_oldsave
922 #define sb_rxtainted    cx_u.cx_subst.sbu_rxtainted
923 #define sb_orig         cx_u.cx_subst.sbu_orig
924 #define sb_dstr         cx_u.cx_subst.sbu_dstr
925 #define sb_targ         cx_u.cx_subst.sbu_targ
926 #define sb_s            cx_u.cx_subst.sbu_s
927 #define sb_m            cx_u.cx_subst.sbu_m
928 #define sb_strend       cx_u.cx_subst.sbu_strend
929 #define sb_rxres        cx_u.cx_subst.sbu_rxres
930 #define sb_rx           cx_u.cx_subst.sbu_rx
931
932 #ifdef PERL_CORE
933 #  define PUSHSUBST(cx) CXINC, cx = &cxstack[cxstack_ix],               \
934         cx->sb_iters            = iters,                                \
935         cx->sb_maxiters         = maxiters,                             \
936         cx->sb_rflags           = r_flags,                              \
937         cx->sb_oldsave          = oldsave,                              \
938         cx->sb_rxtainted        = rxtainted,                            \
939         cx->sb_orig             = orig,                                 \
940         cx->sb_dstr             = dstr,                                 \
941         cx->sb_targ             = targ,                                 \
942         cx->sb_s                = s,                                    \
943         cx->sb_m                = m,                                    \
944         cx->sb_strend           = strend,                               \
945         cx->sb_rxres            = NULL,                                 \
946         cx->sb_rx               = rx,                                   \
947         cx->cx_type             = CXt_SUBST | (once ? CXp_ONCE : 0);    \
948         rxres_save(&cx->sb_rxres, rx);                                  \
949         (void)ReREFCNT_inc(rx);                                         \
950         SvREFCNT_inc_void_NN(targ)
951
952 #  define POPSUBST(cx) cx = &cxstack[cxstack_ix--];                     \
953         rxres_free(&cx->sb_rxres);                                      \
954         ReREFCNT_dec(cx->sb_rx);                                        \
955         SvREFCNT_dec_NN(cx->sb_targ)
956 #endif
957
958 #define CxONCE(cx)              ((cx)->cx_type & CXp_ONCE)
959
960 struct context {
961     union {
962         struct block    cx_blk;
963         struct subst    cx_subst;
964     } cx_u;
965 };
966 #define cx_type cx_u.cx_subst.sbu_type
967
968 /* If you re-order these, there is also an array of uppercase names in perl.h
969    and a static array of context names in pp_ctl.c  */
970 #define CXTYPEMASK      0xf
971 #define CXt_NULL        0
972 #define CXt_WHEN        1
973 #define CXt_BLOCK       2
974 /* When micro-optimising :-) keep GIVEN next to the LOOPs, as these 5 share a
975    jump table in pp_ctl.c
976    The first 4 don't have a 'case' in at least one switch statement in pp_ctl.c
977 */
978 #define CXt_GIVEN       3
979 /* This is first so that CXt_LOOP_FOR|CXt_LOOP_LAZYIV is CXt_LOOP_LAZYIV */
980 #define CXt_LOOP_FOR    4
981 #define CXt_LOOP_PLAIN  5
982 #define CXt_LOOP_LAZYSV 6
983 #define CXt_LOOP_LAZYIV 7
984 #define CXt_SUB         8
985 #define CXt_FORMAT      9
986 #define CXt_EVAL       10
987 #define CXt_SUBST      11
988 /* SUBST doesn't feature in all switch statements.  */
989
990 /* private flags for CXt_SUB and CXt_NULL
991    However, this is checked in many places which do not check the type, so
992    this bit needs to be kept clear for most everything else. For reasons I
993    haven't investigated, it can coexist with CXp_FOR_DEF */
994 #define CXp_MULTICALL   0x10    /* part of a multicall (so don't
995                                    tear down context on exit). */ 
996
997 /* private flags for CXt_SUB and CXt_FORMAT */
998 #define CXp_HASARGS     0x20
999 #define CXp_SUB_RE      0x40    /* code called within regex, i.e. (?{}) */
1000 #define CXp_SUB_RE_FAKE 0x80    /* fake sub CX for (?{}) in current scope */
1001
1002 /* private flags for CXt_EVAL */
1003 #define CXp_REAL        0x20    /* truly eval'', not a lookalike */
1004 #define CXp_TRYBLOCK    0x40    /* eval{}, not eval'' or similar */
1005
1006 /* private flags for CXt_LOOP */
1007 #define CXp_FOR_DEF     0x10    /* foreach using $_ */
1008 #define CXp_FOR_LVREF   0x20    /* foreach using \$var */
1009 #define CxPADLOOP(c)    ((c)->blk_loop.my_op->op_targ)
1010
1011 /* private flags for CXt_SUBST */
1012 #define CXp_ONCE        0x10    /* What was sbu_once in struct subst */
1013
1014 #define CxTYPE(c)       ((c)->cx_type & CXTYPEMASK)
1015 #define CxTYPE_is_LOOP(c)       (((c)->cx_type & 0xC) == 0x4)
1016 #define CxMULTICALL(c)  (((c)->cx_type & CXp_MULTICALL)                 \
1017                          == CXp_MULTICALL)
1018 #define CxREALEVAL(c)   (((c)->cx_type & (CXTYPEMASK|CXp_REAL))         \
1019                          == (CXt_EVAL|CXp_REAL))
1020 #define CxTRYBLOCK(c)   (((c)->cx_type & (CXTYPEMASK|CXp_TRYBLOCK))     \
1021                          == (CXt_EVAL|CXp_TRYBLOCK))
1022 #define CxFOREACH(c)    (CxTYPE_is_LOOP(c) && CxTYPE(c) != CXt_LOOP_PLAIN)
1023 #define CxFOREACHDEF(c) ((CxTYPE_is_LOOP(c) && CxTYPE(c) != CXt_LOOP_PLAIN) \
1024                          && ((c)->cx_type & CXp_FOR_DEF))
1025
1026 #define CXINC (cxstack_ix < cxstack_max ? ++cxstack_ix : (cxstack_ix = cxinc()))
1027
1028 /* 
1029 =head1 "Gimme" Values
1030 */
1031
1032 /*
1033 =for apidoc AmU||G_SCALAR
1034 Used to indicate scalar context.  See C<L</GIMME_V>>, C<L</GIMME>>, and
1035 L<perlcall>.
1036
1037 =for apidoc AmU||G_ARRAY
1038 Used to indicate list context.  See C<L</GIMME_V>>, C<L</GIMME>> and
1039 L<perlcall>.
1040
1041 =for apidoc AmU||G_VOID
1042 Used to indicate void context.  See C<L</GIMME_V>> and L<perlcall>.
1043
1044 =for apidoc AmU||G_DISCARD
1045 Indicates that arguments returned from a callback should be discarded.  See
1046 L<perlcall>.
1047
1048 =for apidoc AmU||G_EVAL
1049
1050 Used to force a Perl C<eval> wrapper around a callback.  See
1051 L<perlcall>.
1052
1053 =for apidoc AmU||G_NOARGS
1054
1055 Indicates that no arguments are being sent to a callback.  See
1056 L<perlcall>.
1057
1058 =cut
1059 */
1060
1061 #define G_SCALAR        2
1062 #define G_ARRAY         3
1063 #define G_VOID          1
1064 #define G_WANT          3
1065
1066 /* extra flags for Perl_call_* routines */
1067 #define G_DISCARD       4       /* Call FREETMPS.
1068                                    Don't change this without consulting the
1069                                    hash actions codes defined in hv.h */
1070 #define G_EVAL          8       /* Assume eval {} around subroutine call. */
1071 #define G_NOARGS       16       /* Don't construct a @_ array. */
1072 #define G_KEEPERR      32       /* Warn for errors, don't overwrite $@ */
1073 #define G_NODEBUG      64       /* Disable debugging at toplevel.  */
1074 #define G_METHOD      128       /* Calling method. */
1075 #define G_FAKINGEVAL  256       /* Faking an eval context for call_sv or
1076                                    fold_constants. */
1077 #define G_UNDEF_FILL  512       /* Fill the stack with &PL_sv_undef
1078                                    A special case for UNSHIFT in
1079                                    Perl_magic_methcall().  */
1080 #define G_WRITING_TO_STDERR 1024 /* Perl_write_to_stderr() is calling
1081                                     Perl_magic_methcall().  */
1082 #define G_RE_REPARSING 0x800     /* compiling a run-time /(?{..})/ */
1083 #define G_METHOD_NAMED 4096     /* calling named method, eg without :: or ' */
1084
1085 /* flag bits for PL_in_eval */
1086 #define EVAL_NULL       0       /* not in an eval */
1087 #define EVAL_INEVAL     1       /* some enclosing scope is an eval */
1088 #define EVAL_WARNONLY   2       /* used by yywarn() when calling yyerror() */
1089 #define EVAL_KEEPERR    4       /* set by Perl_call_sv if G_KEEPERR */
1090 #define EVAL_INREQUIRE  8       /* The code is being required. */
1091 #define EVAL_RE_REPARSING 0x10  /* eval_sv() called with G_RE_REPARSING */
1092
1093 /* Support for switching (stack and block) contexts.
1094  * This ensures magic doesn't invalidate local stack and cx pointers.
1095  */
1096
1097 #define PERLSI_UNKNOWN          -1
1098 #define PERLSI_UNDEF            0
1099 #define PERLSI_MAIN             1
1100 #define PERLSI_MAGIC            2
1101 #define PERLSI_SORT             3
1102 #define PERLSI_SIGNAL           4
1103 #define PERLSI_OVERLOAD         5
1104 #define PERLSI_DESTROY          6
1105 #define PERLSI_WARNHOOK         7
1106 #define PERLSI_DIEHOOK          8
1107 #define PERLSI_REQUIRE          9
1108 #define PERLSI_MULTICALL       10
1109
1110 struct stackinfo {
1111     AV *                si_stack;       /* stack for current runlevel */
1112     PERL_CONTEXT *      si_cxstack;     /* context stack for runlevel */
1113     struct stackinfo *  si_prev;
1114     struct stackinfo *  si_next;
1115     I32                 si_cxix;        /* current context index */
1116     I32                 si_cxmax;       /* maximum allocated index */
1117     I32                 si_type;        /* type of runlevel */
1118     I32                 si_markoff;     /* offset where markstack begins for us.
1119                                          * currently used only with DEBUGGING,
1120                                          * but not #ifdef-ed for bincompat */
1121 };
1122
1123 typedef struct stackinfo PERL_SI;
1124
1125 #define cxstack         (PL_curstackinfo->si_cxstack)
1126 #define cxstack_ix      (PL_curstackinfo->si_cxix)
1127 #define cxstack_max     (PL_curstackinfo->si_cxmax)
1128
1129 #ifdef DEBUGGING
1130 #  define       SET_MARK_OFFSET \
1131     PL_curstackinfo->si_markoff = PL_markstack_ptr - PL_markstack
1132 #else
1133 #  define       SET_MARK_OFFSET NOOP
1134 #endif
1135
1136 #define PUSHSTACKi(type) \
1137     STMT_START {                                                        \
1138         PERL_SI *next = PL_curstackinfo->si_next;                       \
1139         DEBUG_l({                                                       \
1140             int i = 0; PERL_SI *p = PL_curstackinfo;                    \
1141             while (p) { i++; p = p->si_prev; }                          \
1142             Perl_deb(aTHX_ "push STACKINFO %d at %s:%d\n",              \
1143                          i, __FILE__, __LINE__);})                      \
1144         if (!next) {                                                    \
1145             next = new_stackinfo(32, 2048/sizeof(PERL_CONTEXT) - 1);    \
1146             next->si_prev = PL_curstackinfo;                            \
1147             PL_curstackinfo->si_next = next;                            \
1148         }                                                               \
1149         next->si_type = type;                                           \
1150         next->si_cxix = -1;                                             \
1151         AvFILLp(next->si_stack) = 0;                                    \
1152         SWITCHSTACK(PL_curstack,next->si_stack);                        \
1153         PL_curstackinfo = next;                                         \
1154         SET_MARK_OFFSET;                                                \
1155     } STMT_END
1156
1157 #define PUSHSTACK PUSHSTACKi(PERLSI_UNKNOWN)
1158
1159 /* POPSTACK works with PL_stack_sp, so it may need to be bracketed by
1160  * PUTBACK/SPAGAIN to flush/refresh any local SP that may be active */
1161 #define POPSTACK \
1162     STMT_START {                                                        \
1163         dSP;                                                            \
1164         PERL_SI * const prev = PL_curstackinfo->si_prev;                \
1165         DEBUG_l({                                                       \
1166             int i = -1; PERL_SI *p = PL_curstackinfo;                   \
1167             while (p) { i++; p = p->si_prev; }                          \
1168             Perl_deb(aTHX_ "pop  STACKINFO %d at %s:%d\n",              \
1169                          i, __FILE__, __LINE__);})                      \
1170         if (!prev) {                                                    \
1171             Perl_croak_popstack();                                      \
1172         }                                                               \
1173         SWITCHSTACK(PL_curstack,prev->si_stack);                        \
1174         /* don't free prev here, free them all at the END{} */          \
1175         PL_curstackinfo = prev;                                         \
1176     } STMT_END
1177
1178 #define POPSTACK_TO(s) \
1179     STMT_START {                                                        \
1180         while (PL_curstack != s) {                                      \
1181             dounwind(-1);                                               \
1182             POPSTACK;                                                   \
1183         }                                                               \
1184     } STMT_END
1185
1186 #define IN_PERL_COMPILETIME     (PL_curcop == &PL_compiling)
1187 #define IN_PERL_RUNTIME         (PL_curcop != &PL_compiling)
1188
1189 /*
1190 =head1 Multicall Functions
1191
1192 =for apidoc Ams||dMULTICALL
1193 Declare local variables for a multicall.  See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1194
1195 =for apidoc Ams||PUSH_MULTICALL
1196 Opening bracket for a lightweight callback.
1197 See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1198
1199 =for apidoc Ams||MULTICALL
1200 Make a lightweight callback.  See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1201
1202 =for apidoc Ams||POP_MULTICALL
1203 Closing bracket for a lightweight callback.
1204 See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1205
1206 =cut
1207 */
1208
1209 #define dMULTICALL \
1210     SV **newsp;                 /* set by POPBLOCK */                   \
1211     PERL_CONTEXT *cx;                                                   \
1212     CV *multicall_cv;                                                   \
1213     OP *multicall_cop;                                                  \
1214     bool multicall_oldcatch;                                            \
1215     U8 hasargs = 0              /* used by PUSHSUB */
1216
1217 #define PUSH_MULTICALL(the_cv) \
1218     PUSH_MULTICALL_FLAGS(the_cv, 0)
1219
1220 /* Like PUSH_MULTICALL, but allows you to specify extra flags
1221  * for the CX stack entry (this isn't part of the public API) */
1222
1223 #define PUSH_MULTICALL_FLAGS(the_cv, flags) \
1224     STMT_START {                                                        \
1225         CV * const _nOnclAshIngNamE_ = the_cv;                          \
1226         CV * const cv = _nOnclAshIngNamE_;                              \
1227         PADLIST * const padlist = CvPADLIST(cv);                        \
1228         ENTER;                                                          \
1229         multicall_oldcatch = CATCH_GET;                                 \
1230         SAVEVPTR(PL_op);                                                \
1231         CATCH_SET(TRUE);                                                \
1232         PUSHSTACKi(PERLSI_MULTICALL);                                   \
1233         PUSHBLOCK(cx, (CXt_SUB|CXp_MULTICALL|flags), PL_stack_sp);      \
1234         PUSHSUB(cx);                                                    \
1235         if (!(flags & CXp_SUB_RE_FAKE))                                 \
1236             CvDEPTH(cv)++;                                              \
1237         if (CvDEPTH(cv) >= 2) {                                         \
1238             PERL_STACK_OVERFLOW_CHECK();                                \
1239             Perl_pad_push(aTHX_ padlist, CvDEPTH(cv));                  \
1240         }                                                               \
1241         PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));                       \
1242         multicall_cv = cv;                                              \
1243         multicall_cop = CvSTART(cv);                                    \
1244     } STMT_END
1245
1246 #define MULTICALL \
1247     STMT_START {                                                        \
1248         PL_op = multicall_cop;                                          \
1249         CALLRUNOPS(aTHX);                                               \
1250     } STMT_END
1251
1252 #define POP_MULTICALL \
1253     STMT_START {                                                        \
1254         cx = &cxstack[cxstack_ix];                                      \
1255         CvDEPTH(multicall_cv) = cx->blk_sub.olddepth;                   \
1256         LEAVESUB(multicall_cv);                                         \
1257         POPBLOCK(cx,PL_curpm);                                          \
1258         /* includes partial unrolled POPSUB(): */                       \
1259         LEAVE_SCOPE(PL_scopestack[cx->blk_oldscopesp-1]);               \
1260         PL_comppad = cx->blk_sub.prevcomppad;                           \
1261         PL_curpad = LIKELY(PL_comppad) ? AvARRAY(PL_comppad) : NULL;    \
1262         POPSTACK;                                                       \
1263         CATCH_SET(multicall_oldcatch);                                  \
1264         LEAVE;                                                          \
1265         SPAGAIN;                                                        \
1266     } STMT_END
1267
1268 /* Change the CV of an already-pushed MULTICALL CxSUB block.
1269  * (this isn't part of the public API) */
1270
1271 #define CHANGE_MULTICALL_FLAGS(the_cv, flags) \
1272     STMT_START {                                                        \
1273         CV * const _nOnclAshIngNamE_ = the_cv;                          \
1274         CV * const cv = _nOnclAshIngNamE_;                              \
1275         PADLIST * const padlist = CvPADLIST(cv);                        \
1276         cx = &cxstack[cxstack_ix];                                      \
1277         assert(cx->cx_type & CXp_MULTICALL);                            \
1278         CvDEPTH(multicall_cv) = cx->blk_sub.olddepth;                   \
1279         LEAVESUB(multicall_cv);                                         \
1280         cx->cx_type = (CXt_SUB|CXp_MULTICALL|flags);                    \
1281         {                                                               \
1282             /* save a few things that we don't want PUSHSUB to zap */   \
1283             PAD * const prevcomppad = cx->blk_sub.prevcomppad;          \
1284             SSize_t old_floor = cx->blk_sub.old_tmpsfloor;              \
1285             SSize_t floor = PL_tmps_floor;                              \
1286             PUSHSUB(cx);                                                \
1287             /* undo the stuff that PUSHSUB zapped */                    \
1288             cx->blk_sub.prevcomppad = prevcomppad ;                     \
1289             cx->blk_sub.old_tmpsfloor = old_floor;                      \
1290             PL_tmps_floor = floor;                                      \
1291         }                                                               \
1292         if (!(flags & CXp_SUB_RE_FAKE))                                 \
1293             CvDEPTH(cv)++;                                              \
1294         if (CvDEPTH(cv) >= 2) {                                         \
1295             PERL_STACK_OVERFLOW_CHECK();                                \
1296             Perl_pad_push(aTHX_ padlist, CvDEPTH(cv));                  \
1297         }                                                               \
1298         PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));                       \
1299         multicall_cv = cv;                                              \
1300         multicall_cop = CvSTART(cv);                                    \
1301     } STMT_END
1302 /*
1303  * ex: set ts=8 sts=4 sw=4 et:
1304  */