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[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     PAD         *prevcomppad; /* the caller's PL_comppad */
555     CV *        cv;
556     /* Above here is the same for sub and format.  */
557     I32         olddepth;
558     AV          *savearray;
559 };
560
561
562 /* format context */
563 struct block_format {
564     OP *        retop;  /* op to execute on exit from sub */
565     /* Above here is the same for sub, format and eval.  */
566     PAD         *prevcomppad; /* the caller's PL_comppad */
567     CV *        cv;
568     /* Above here is the same for sub and format.  */
569     GV *        gv;
570     GV *        dfoutgv;
571 };
572
573 /* base for the next two macros. Don't use directly.
574  * The context frame holds a reference to the CV so that it can't be
575  * freed while we're executing it */
576
577 #define PUSHSUB_BASE(cx)                                                \
578         ENTRY_PROBE(CvNAMED(cv)                                         \
579                         ? HEK_KEY(CvNAME_HEK(cv))                       \
580                         : GvENAME(CvGV(cv)),                            \
581                 CopFILE((const COP *)CvSTART(cv)),                      \
582                 CopLINE((const COP *)CvSTART(cv)),                      \
583                 CopSTASHPV((const COP *)CvSTART(cv)));                  \
584                                                                         \
585         cx->blk_sub.cv = cv;                                            \
586         cx->blk_sub.olddepth = CvDEPTH(cv);                             \
587         cx->blk_sub.prevcomppad = PL_comppad;                           \
588         cx->cx_type |= (hasargs) ? CXp_HASARGS : 0;                     \
589         cx->blk_sub.retop = NULL;                                       \
590         SvREFCNT_inc_simple_void_NN(cv);                                \
591         cx->cx_u.cx_blk.blku_old_tmpsfloor = PL_tmps_floor;             \
592         PL_tmps_floor = PL_tmps_ix;
593
594 #define PUSHSUB_GET_LVALUE_MASK(func) \
595         /* If the context is indeterminate, then only the lvalue */     \
596         /* flags that the caller also has are applicable.        */     \
597         (                                                               \
598            (PL_op->op_flags & OPf_WANT)                                 \
599                ? OPpENTERSUB_LVAL_MASK                                  \
600                : !(PL_op->op_private & OPpENTERSUB_LVAL_MASK)           \
601                    ? 0 : (U8)func(aTHX)                                 \
602         )
603
604 #define PUSHSUB(cx)                                                     \
605     {                                                                   \
606         U8 phlags = PUSHSUB_GET_LVALUE_MASK(Perl_was_lvalue_sub);       \
607         PUSHSUB_BASE(cx)                                                \
608         cx->blk_u16 = PL_op->op_private &                               \
609                           (phlags|OPpDEREF);                            \
610     }
611
612 /* variant for use by OP_DBSTATE, where op_private holds hint bits */
613 #define PUSHSUB_DB(cx)                                                  \
614         PUSHSUB_BASE(cx)                                                \
615         cx->blk_u16 = 0;
616
617
618 #define PUSHFORMAT(cx, retop)                                           \
619         cx->blk_format.cv = cv;                                         \
620         cx->blk_format.gv = gv;                                         \
621         cx->blk_format.retop = (retop);                                 \
622         cx->blk_format.dfoutgv = PL_defoutgv;                           \
623         cx->blk_format.prevcomppad = PL_comppad;                        \
624         cx->blk_u16 = 0;                                                \
625         cx->cx_u.cx_blk.blku_old_savestack_ix = PL_savestack_ix;        \
626         cx->cx_u.cx_blk.blku_old_tmpsfloor = PL_tmps_floor;             \
627         PL_tmps_floor = PL_tmps_ix;                                     \
628         SvREFCNT_inc_simple_void_NN(cv);                                \
629         CvDEPTH(cv)++;                                                  \
630         SvREFCNT_inc_void(cx->blk_format.dfoutgv)
631
632 /* Restore old @_ */
633 #define POP_SAVEARRAY()                                         \
634     STMT_START {                                                        \
635         AV *av = GvAV(PL_defgv);                                        \
636         GvAV(PL_defgv) = cx->blk_sub.savearray;                         \
637         SvREFCNT_dec(av);                                               \
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         LEAVE_SCOPE(cx->cx_u.cx_blk.blku_old_savestack_ix);             \
652         if (!(cx->blk_u16 & CxPOPSUB_DONE)) {                           \
653         cx->blk_u16 |= CxPOPSUB_DONE;                                   \
654         RETURN_PROBE(CvNAMED(cx->blk_sub.cv)                            \
655                         ? HEK_KEY(CvNAME_HEK(cx->blk_sub.cv))           \
656                         : GvENAME(CvGV(cx->blk_sub.cv)),                \
657                 CopFILE((COP*)CvSTART((const CV*)cx->blk_sub.cv)),      \
658                 CopLINE((COP*)CvSTART((const CV*)cx->blk_sub.cv)),      \
659                 CopSTASHPV((COP*)CvSTART((const CV*)cx->blk_sub.cv)));  \
660                                                                         \
661         if (CxHASARGS(cx)) {                                            \
662             AV *av;                                                     \
663             assert(AvARRAY(MUTABLE_AV(                                  \
664                 PadlistARRAY(CvPADLIST(cx->blk_sub.cv))[                \
665                         CvDEPTH(cx->blk_sub.cv)])) == PL_curpad);       \
666             POP_SAVEARRAY();                                            \
667             /* abandon @_ if it got reified */                          \
668             av = MUTABLE_AV(PAD_SVl(0));                                \
669             if (UNLIKELY(AvREAL(av)))                                   \
670                 clear_defarray(av, 0);                                  \
671             else {                                                      \
672                 CLEAR_ARGARRAY(av);                                     \
673             }                                                           \
674         }                                                               \
675         }                                                               \
676         PL_tmps_floor = cx->cx_u.cx_blk.blku_old_tmpsfloor;             \
677         PL_comppad = cx->blk_sub.prevcomppad;                           \
678         PL_curpad = LIKELY(PL_comppad) ? AvARRAY(PL_comppad) : NULL;    \
679         sv = MUTABLE_SV(cx->blk_sub.cv);                                \
680         CvDEPTH((const CV*)sv) = cx->blk_sub.olddepth;                  \
681     } STMT_END
682
683 #define LEAVESUB(sv)                                                    \
684     STMT_START {                                                        \
685         SvREFCNT_dec(sv);                                               \
686     } STMT_END
687
688 #define POPFORMAT(cx)                                                   \
689     STMT_START {                                                        \
690         LEAVE_SCOPE(cx->cx_u.cx_blk.blku_old_savestack_ix);             \
691         if (!(cx->blk_u16 & CxPOPSUB_DONE)) {                           \
692         CV * const cv = cx->blk_format.cv;                              \
693         GV * const dfuot = cx->blk_format.dfoutgv;                      \
694         cx->blk_u16 |= CxPOPSUB_DONE;                                   \
695         PL_tmps_floor = cx->cx_u.cx_blk.blku_old_tmpsfloor;             \
696         setdefout(dfuot);                                               \
697         PL_comppad = cx->blk_format.prevcomppad;                        \
698         PL_curpad = LIKELY(PL_comppad) ? AvARRAY(PL_comppad) : NULL;    \
699         --CvDEPTH(cv);                                                  \
700         SvREFCNT_dec_NN(cx->blk_format.cv);                             \
701         SvREFCNT_dec_NN(dfuot);                                         \
702         }                                                               \
703     } STMT_END
704
705 /* eval context */
706 struct block_eval {
707     OP *        retop;  /* op to execute on exit from eval */
708     /* Above here is the same for sub, format and eval.  */
709     SV *        old_namesv;
710     OP *        old_eval_root;
711     SV *        cur_text;
712     CV *        cv;
713     JMPENV *    cur_top_env; /* value of PL_top_env when eval CX created */
714 };
715
716 /* If we ever need more than 512 op types, change the shift from 7.
717    blku_gimme is actually also only 2 bits, so could be merged with something.
718 */
719
720 #define CxOLD_IN_EVAL(cx)       (((cx)->blk_u16) & 0x7F)
721 #define CxOLD_OP_TYPE(cx)       (((cx)->blk_u16) >> 7)
722
723 #define PUSHEVAL(cx,n)                                                  \
724     STMT_START {                                                        \
725         assert(!(PL_in_eval & ~0x7F));                                  \
726         assert(!(PL_op->op_type & ~0x1FF));                             \
727         cx->blk_u16 = (PL_in_eval & 0x7F) | ((U16)PL_op->op_type << 7); \
728         cx->cx_u.cx_blk.blku_old_tmpsfloor = PL_tmps_floor;             \
729         PL_tmps_floor = PL_tmps_ix;                                     \
730         cx->blk_eval.old_namesv = (n ? newSVpv(n,0) : NULL);            \
731         cx->blk_eval.old_eval_root = PL_eval_root;                      \
732         cx->blk_eval.cur_text = PL_parser ? PL_parser->linestr : NULL;  \
733         cx->blk_eval.cv = NULL; /* set by doeval(), as applicable */    \
734         cx->blk_eval.retop = NULL;                                      \
735         cx->blk_eval.cur_top_env = PL_top_env;                          \
736     } STMT_END
737
738 #define POPEVAL(cx)                                                     \
739     STMT_START {                                                        \
740         PL_in_eval = CxOLD_IN_EVAL(cx);                                 \
741         optype = CxOLD_OP_TYPE(cx);                                     \
742         PL_eval_root = cx->blk_eval.old_eval_root;                      \
743         if (cx->blk_eval.cur_text && SvSCREAM(cx->blk_eval.cur_text))   \
744             SvREFCNT_dec_NN(cx->blk_eval.cur_text);                     \
745         if (cx->blk_eval.old_namesv)                                    \
746             sv_2mortal(cx->blk_eval.old_namesv);                        \
747     } STMT_END
748
749 /* loop context */
750 struct block_loop {
751     I32         resetsp;
752     LOOP *      my_op;  /* My op, that contains redo, next and last ops.  */
753     union {     /* different ways of locating the iteration variable */
754         SV      **svp; /* for lexicals: address of pad slot */
755         GV      *gv;   /* for package vars */
756     } itervar_u;
757     SV          *itersave; /* the original iteration var */
758     union {
759         struct { /* valid if type is LOOP_FOR or LOOP_PLAIN (but {NULL,0})*/
760             AV * ary; /* use the stack if this is NULL */
761             IV ix;
762         } ary;
763         struct { /* valid if type is LOOP_LAZYIV */
764             IV cur;
765             IV end;
766         } lazyiv;
767         struct { /* valid if type if LOOP_LAZYSV */
768             SV * cur;
769             SV * end; /* maxiumum value (or minimum in reverse) */
770         } lazysv;
771     } state_u;
772 #ifdef USE_ITHREADS
773     PAD *oldcomppad; /* needed to map itervar_u.svp during thread clone */
774 #endif
775 };
776
777 #define CxITERVAR(c)                                    \
778         (CxPADLOOP(c)                                   \
779             ? (c)->blk_loop.itervar_u.svp               \
780             : ((c)->cx_type & CXp_FOR_GV)               \
781                 ? &GvSV((c)->blk_loop.itervar_u.gv)     \
782                 : (SV **)&(c)->blk_loop.itervar_u.gv)
783
784 #define CxLABEL(c)      (0 + CopLABEL((c)->blk_oldcop))
785 #define CxLABEL_len(c,len)      (0 + CopLABEL_len((c)->blk_oldcop, len))
786 #define CxLABEL_len_flags(c,len,flags)  (0 + CopLABEL_len_flags((c)->blk_oldcop, len, flags))
787 #define CxHASARGS(c)    (((c)->cx_type & CXp_HASARGS) == CXp_HASARGS)
788 #define CxLVAL(c)       (0 + ((c)->blk_u16 & 0xff))
789 /* POPSUB has already been performed on this context frame */
790 #define CxPOPSUB_DONE 0x100
791
792
793 #define PUSHLOOP_PLAIN(cx, s)                                           \
794         cx->blk_loop.resetsp = s - PL_stack_base;                       \
795         cx->blk_loop.my_op = cLOOP;                                     \
796         cx->blk_loop.state_u.ary.ary = NULL;                            \
797         cx->blk_loop.state_u.ary.ix = 0;                                \
798         cx->cx_u.cx_blk.blku_old_savestack_ix = PL_savestack_ix;        \
799         cx->blk_loop.itervar_u.svp = NULL;                              \
800         cx->blk_loop.itersave = NULL;
801
802 #ifdef USE_ITHREADS
803 #  define PUSHLOOP_FOR_setpad(c) (c)->blk_loop.oldcomppad = PL_comppad
804 #else
805 #  define PUSHLOOP_FOR_setpad(c) NOOP
806 #endif
807
808 #define PUSHLOOP_FOR(cx, ivar, isave, s)                                \
809         cx->blk_loop.resetsp = s - PL_stack_base;                       \
810         cx->blk_loop.my_op = cLOOP;                                     \
811         cx->blk_loop.state_u.ary.ary = NULL;                            \
812         cx->blk_loop.state_u.ary.ix = 0;                                \
813         cx->blk_loop.itervar_u.svp = (SV**)(ivar);                      \
814         cx->cx_u.cx_blk.blku_old_savestack_ix = PL_savestack_ix;        \
815         cx->blk_loop.itersave = isave;                                  \
816         PUSHLOOP_FOR_setpad(cx);
817
818 #define POPLOOP(cx)                                                     \
819         LEAVE_SCOPE(cx->cx_u.cx_blk.blku_old_savestack_ix);             \
820         if (CxTYPE(cx) == CXt_LOOP_LAZYSV) {                            \
821             SvREFCNT_dec_NN(cx->blk_loop.state_u.lazysv.cur);           \
822             SvREFCNT_dec_NN(cx->blk_loop.state_u.lazysv.end);           \
823         }                                                               \
824         else if (CxTYPE(cx) == CXt_LOOP_FOR)                            \
825             SvREFCNT_dec(cx->blk_loop.state_u.ary.ary);                 \
826         if (cx->cx_type & (CXp_FOR_PAD|CXp_FOR_GV)) {                   \
827             SV *cursv;                                                  \
828             SV **svp = (cx)->blk_loop.itervar_u.svp;                    \
829             if ((cx->cx_type & CXp_FOR_GV))                             \
830                 svp = &GvSV((GV*)svp);                                  \
831             cursv = *svp;                                               \
832             *svp = cx->blk_loop.itersave;                               \
833             SvREFCNT_dec(cursv);                                        \
834         }
835
836 /* given/when context */
837 struct block_givwhen {
838         OP *leave_op;
839 };
840
841 #define PUSHGIVEN(cx)                                                   \
842         cx->blk_givwhen.leave_op = cLOGOP->op_other;
843
844 #define PUSHWHEN PUSHGIVEN
845
846 /* context common to subroutines, evals and loops */
847 struct block {
848     U8          blku_type;      /* what kind of context this is */
849     U8          blku_gimme;     /* is this block running in list context? */
850     U16         blku_u16;       /* used by block_sub and block_eval (so far) */
851     I32         blku_oldsp;     /* stack pointer to copy stuff down to */
852     COP *       blku_oldcop;    /* old curcop pointer */
853     I32         blku_oldmarksp; /* mark stack index */
854     I32         blku_oldscopesp;        /* scope stack index */
855     PMOP *      blku_oldpm;     /* values of pattern match vars */
856     SSize_t     blku_old_tmpsfloor;     /* saved PL_tmps_floor */
857     I32         blku_old_savestack_ix;  /* saved PL_savestack_ix */
858
859     union {
860         struct block_sub        blku_sub;
861         struct block_format     blku_format;
862         struct block_eval       blku_eval;
863         struct block_loop       blku_loop;
864         struct block_givwhen    blku_givwhen;
865     } blk_u;
866 };
867 #define blk_oldsp       cx_u.cx_blk.blku_oldsp
868 #define blk_oldcop      cx_u.cx_blk.blku_oldcop
869 #define blk_oldmarksp   cx_u.cx_blk.blku_oldmarksp
870 #define blk_oldscopesp  cx_u.cx_blk.blku_oldscopesp
871 #define blk_oldpm       cx_u.cx_blk.blku_oldpm
872 #define blk_gimme       cx_u.cx_blk.blku_gimme
873 #define blk_u16         cx_u.cx_blk.blku_u16
874 #define blk_sub         cx_u.cx_blk.blk_u.blku_sub
875 #define blk_format      cx_u.cx_blk.blk_u.blku_format
876 #define blk_eval        cx_u.cx_blk.blk_u.blku_eval
877 #define blk_loop        cx_u.cx_blk.blk_u.blku_loop
878 #define blk_givwhen     cx_u.cx_blk.blk_u.blku_givwhen
879
880 #define DEBUG_CX(action)                                                \
881     DEBUG_l(                                                            \
882         Perl_deb(aTHX_ "CX %ld %s %s (scope %ld,%ld) (save %ld,%ld) at %s:%d\n",\
883                     (long)cxstack_ix,                                   \
884                     action,                                             \
885                     PL_block_type[CxTYPE(&cxstack[cxstack_ix])],        \
886                     (long)PL_scopestack_ix,                             \
887                     (long)(cxstack[cxstack_ix].blk_oldscopesp),         \
888                     (long)PL_savestack_ix,                              \
889                     (long)(cxstack[cxstack_ix].cx_u.cx_blk.blku_old_savestack_ix),\
890                     __FILE__, __LINE__));
891
892 /* Enter a block. */
893 #define PUSHBLOCK(cx,t,sp) CXINC, cx = &cxstack[cxstack_ix],            \
894         cx->cx_type             = t,                                    \
895         cx->blk_oldsp           = sp - PL_stack_base,                   \
896         cx->blk_oldcop          = PL_curcop,                            \
897         cx->blk_oldmarksp       = PL_markstack_ptr - PL_markstack,      \
898         cx->blk_oldscopesp      = PL_scopestack_ix,                     \
899         cx->blk_oldpm           = PL_curpm,                             \
900         cx->blk_gimme           = (U8)gimme;                            \
901         DEBUG_CX("PUSH");
902
903 /* Exit a block (RETURN and LAST). */
904 #define POPBLOCK(cx,pm)                                                 \
905         DEBUG_CX("POP");                                                \
906         cx = &cxstack[cxstack_ix--],                                    \
907         newsp            = PL_stack_base + cx->blk_oldsp,               \
908         PL_curcop        = cx->blk_oldcop,                              \
909         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
910         PL_scopestack_ix = cx->blk_oldscopesp,                          \
911         pm               = cx->blk_oldpm,                               \
912         gimme            = cx->blk_gimme;
913
914 /* Continue a block elsewhere (NEXT and REDO). */
915 #define TOPBLOCK(cx)                                                    \
916         DEBUG_CX("TOP");                                                \
917         cx  = &cxstack[cxstack_ix],                                     \
918         PL_stack_sp      = PL_stack_base + cx->blk_oldsp,               \
919         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
920         PL_scopestack_ix = cx->blk_oldscopesp,                          \
921         PL_curpm         = cx->blk_oldpm;
922
923 /* substitution context */
924 struct subst {
925     U8          sbu_type;       /* what kind of context this is */
926     U8          sbu_rflags;
927     U16         sbu_rxtainted;  /* matches struct block */
928     I32         sbu_oldsave;
929     SSize_t     sbu_iters;
930     SSize_t     sbu_maxiters;
931     char *      sbu_orig;
932     SV *        sbu_dstr;
933     SV *        sbu_targ;
934     char *      sbu_s;
935     char *      sbu_m;
936     char *      sbu_strend;
937     void *      sbu_rxres;
938     REGEXP *    sbu_rx;
939 };
940 #define sb_iters        cx_u.cx_subst.sbu_iters
941 #define sb_maxiters     cx_u.cx_subst.sbu_maxiters
942 #define sb_rflags       cx_u.cx_subst.sbu_rflags
943 #define sb_oldsave      cx_u.cx_subst.sbu_oldsave
944 #define sb_rxtainted    cx_u.cx_subst.sbu_rxtainted
945 #define sb_orig         cx_u.cx_subst.sbu_orig
946 #define sb_dstr         cx_u.cx_subst.sbu_dstr
947 #define sb_targ         cx_u.cx_subst.sbu_targ
948 #define sb_s            cx_u.cx_subst.sbu_s
949 #define sb_m            cx_u.cx_subst.sbu_m
950 #define sb_strend       cx_u.cx_subst.sbu_strend
951 #define sb_rxres        cx_u.cx_subst.sbu_rxres
952 #define sb_rx           cx_u.cx_subst.sbu_rx
953
954 #ifdef PERL_CORE
955 #  define PUSHSUBST(cx) CXINC, cx = &cxstack[cxstack_ix],               \
956         cx->sb_iters            = iters,                                \
957         cx->sb_maxiters         = maxiters,                             \
958         cx->sb_rflags           = r_flags,                              \
959         cx->sb_oldsave          = oldsave,                              \
960         cx->sb_rxtainted        = rxtainted,                            \
961         cx->sb_orig             = orig,                                 \
962         cx->sb_dstr             = dstr,                                 \
963         cx->sb_targ             = targ,                                 \
964         cx->sb_s                = s,                                    \
965         cx->sb_m                = m,                                    \
966         cx->sb_strend           = strend,                               \
967         cx->sb_rxres            = NULL,                                 \
968         cx->sb_rx               = rx,                                   \
969         cx->cx_type             = CXt_SUBST | (once ? CXp_ONCE : 0);    \
970         rxres_save(&cx->sb_rxres, rx);                                  \
971         (void)ReREFCNT_inc(rx);                                         \
972         SvREFCNT_inc_void_NN(targ)
973
974 #  define POPSUBST(cx) cx = &cxstack[cxstack_ix--];                     \
975         rxres_free(&cx->sb_rxres);                                      \
976         ReREFCNT_dec(cx->sb_rx);                                        \
977         SvREFCNT_dec_NN(cx->sb_targ)
978 #endif
979
980 #define CxONCE(cx)              ((cx)->cx_type & CXp_ONCE)
981
982 struct context {
983     union {
984         struct block    cx_blk;
985         struct subst    cx_subst;
986     } cx_u;
987 };
988 #define cx_type cx_u.cx_subst.sbu_type
989
990 /* If you re-order these, there is also an array of uppercase names in perl.h
991    and a static array of context names in pp_ctl.c  */
992 #define CXTYPEMASK      0xf
993 #define CXt_NULL        0
994 #define CXt_WHEN        1
995 #define CXt_BLOCK       2
996 /* When micro-optimising :-) keep GIVEN next to the LOOPs, as these 5 share a
997    jump table in pp_ctl.c
998    The first 4 don't have a 'case' in at least one switch statement in pp_ctl.c
999 */
1000 #define CXt_GIVEN       3
1001 /* This is first so that CXt_LOOP_FOR|CXt_LOOP_LAZYIV is CXt_LOOP_LAZYIV */
1002 #define CXt_LOOP_FOR    4
1003 #define CXt_LOOP_PLAIN  5
1004 #define CXt_LOOP_LAZYSV 6
1005 #define CXt_LOOP_LAZYIV 7
1006 #define CXt_SUB         8
1007 #define CXt_FORMAT      9
1008 #define CXt_EVAL       10
1009 #define CXt_SUBST      11
1010 /* SUBST doesn't feature in all switch statements.  */
1011
1012 /* private flags for CXt_SUB and CXt_NULL
1013    However, this is checked in many places which do not check the type, so
1014    this bit needs to be kept clear for most everything else. For reasons I
1015    haven't investigated, it can coexist with CXp_FOR_DEF */
1016 #define CXp_MULTICALL   0x10    /* part of a multicall (so don't
1017                                    tear down context on exit). */ 
1018
1019 /* private flags for CXt_SUB and CXt_FORMAT */
1020 #define CXp_HASARGS     0x20
1021 #define CXp_SUB_RE      0x40    /* code called within regex, i.e. (?{}) */
1022 #define CXp_SUB_RE_FAKE 0x80    /* fake sub CX for (?{}) in current scope */
1023
1024 /* private flags for CXt_EVAL */
1025 #define CXp_REAL        0x20    /* truly eval'', not a lookalike */
1026 #define CXp_TRYBLOCK    0x40    /* eval{}, not eval'' or similar */
1027
1028 /* private flags for CXt_LOOP */
1029 #define CXp_FOR_DEF     0x10    /* foreach using $_ */
1030 #define CXp_FOR_LVREF   0x20    /* foreach using \$var */
1031 #define CXp_FOR_GV      0x40    /* foreach using package var */
1032 #define CXp_FOR_PAD     0x80    /* foreach using lexical var */
1033 #define CxPADLOOP(c)    ((c)->cx_type & CXp_FOR_PAD)
1034
1035 /* private flags for CXt_SUBST */
1036 #define CXp_ONCE        0x10    /* What was sbu_once in struct subst */
1037
1038 #define CxTYPE(c)       ((c)->cx_type & CXTYPEMASK)
1039 #define CxTYPE_is_LOOP(c)       (((c)->cx_type & 0xC) == 0x4)
1040 #define CxMULTICALL(c)  (((c)->cx_type & CXp_MULTICALL)                 \
1041                          == CXp_MULTICALL)
1042 #define CxREALEVAL(c)   (((c)->cx_type & (CXTYPEMASK|CXp_REAL))         \
1043                          == (CXt_EVAL|CXp_REAL))
1044 #define CxTRYBLOCK(c)   (((c)->cx_type & (CXTYPEMASK|CXp_TRYBLOCK))     \
1045                          == (CXt_EVAL|CXp_TRYBLOCK))
1046 #define CxFOREACH(c)    (CxTYPE_is_LOOP(c) && CxTYPE(c) != CXt_LOOP_PLAIN)
1047 #define CxFOREACHDEF(c) ((CxTYPE_is_LOOP(c) && CxTYPE(c) != CXt_LOOP_PLAIN) \
1048                          && ((c)->cx_type & CXp_FOR_DEF))
1049
1050 #define CXINC (cxstack_ix < cxstack_max ? ++cxstack_ix : (cxstack_ix = cxinc()))
1051
1052 /* 
1053 =head1 "Gimme" Values
1054 */
1055
1056 /*
1057 =for apidoc AmU||G_SCALAR
1058 Used to indicate scalar context.  See C<L</GIMME_V>>, C<L</GIMME>>, and
1059 L<perlcall>.
1060
1061 =for apidoc AmU||G_ARRAY
1062 Used to indicate list context.  See C<L</GIMME_V>>, C<L</GIMME>> and
1063 L<perlcall>.
1064
1065 =for apidoc AmU||G_VOID
1066 Used to indicate void context.  See C<L</GIMME_V>> and L<perlcall>.
1067
1068 =for apidoc AmU||G_DISCARD
1069 Indicates that arguments returned from a callback should be discarded.  See
1070 L<perlcall>.
1071
1072 =for apidoc AmU||G_EVAL
1073
1074 Used to force a Perl C<eval> wrapper around a callback.  See
1075 L<perlcall>.
1076
1077 =for apidoc AmU||G_NOARGS
1078
1079 Indicates that no arguments are being sent to a callback.  See
1080 L<perlcall>.
1081
1082 =cut
1083 */
1084
1085 #define G_SCALAR        2
1086 #define G_ARRAY         3
1087 #define G_VOID          1
1088 #define G_WANT          3
1089
1090 /* extra flags for Perl_call_* routines */
1091 #define G_DISCARD       4       /* Call FREETMPS.
1092                                    Don't change this without consulting the
1093                                    hash actions codes defined in hv.h */
1094 #define G_EVAL          8       /* Assume eval {} around subroutine call. */
1095 #define G_NOARGS       16       /* Don't construct a @_ array. */
1096 #define G_KEEPERR      32       /* Warn for errors, don't overwrite $@ */
1097 #define G_NODEBUG      64       /* Disable debugging at toplevel.  */
1098 #define G_METHOD      128       /* Calling method. */
1099 #define G_FAKINGEVAL  256       /* Faking an eval context for call_sv or
1100                                    fold_constants. */
1101 #define G_UNDEF_FILL  512       /* Fill the stack with &PL_sv_undef
1102                                    A special case for UNSHIFT in
1103                                    Perl_magic_methcall().  */
1104 #define G_WRITING_TO_STDERR 1024 /* Perl_write_to_stderr() is calling
1105                                     Perl_magic_methcall().  */
1106 #define G_RE_REPARSING 0x800     /* compiling a run-time /(?{..})/ */
1107 #define G_METHOD_NAMED 4096     /* calling named method, eg without :: or ' */
1108
1109 /* flag bits for PL_in_eval */
1110 #define EVAL_NULL       0       /* not in an eval */
1111 #define EVAL_INEVAL     1       /* some enclosing scope is an eval */
1112 #define EVAL_WARNONLY   2       /* used by yywarn() when calling yyerror() */
1113 #define EVAL_KEEPERR    4       /* set by Perl_call_sv if G_KEEPERR */
1114 #define EVAL_INREQUIRE  8       /* The code is being required. */
1115 #define EVAL_RE_REPARSING 0x10  /* eval_sv() called with G_RE_REPARSING */
1116
1117 /* Support for switching (stack and block) contexts.
1118  * This ensures magic doesn't invalidate local stack and cx pointers.
1119  */
1120
1121 #define PERLSI_UNKNOWN          -1
1122 #define PERLSI_UNDEF            0
1123 #define PERLSI_MAIN             1
1124 #define PERLSI_MAGIC            2
1125 #define PERLSI_SORT             3
1126 #define PERLSI_SIGNAL           4
1127 #define PERLSI_OVERLOAD         5
1128 #define PERLSI_DESTROY          6
1129 #define PERLSI_WARNHOOK         7
1130 #define PERLSI_DIEHOOK          8
1131 #define PERLSI_REQUIRE          9
1132 #define PERLSI_MULTICALL       10
1133
1134 struct stackinfo {
1135     AV *                si_stack;       /* stack for current runlevel */
1136     PERL_CONTEXT *      si_cxstack;     /* context stack for runlevel */
1137     struct stackinfo *  si_prev;
1138     struct stackinfo *  si_next;
1139     I32                 si_cxix;        /* current context index */
1140     I32                 si_cxmax;       /* maximum allocated index */
1141     I32                 si_type;        /* type of runlevel */
1142     I32                 si_markoff;     /* offset where markstack begins for us.
1143                                          * currently used only with DEBUGGING,
1144                                          * but not #ifdef-ed for bincompat */
1145 };
1146
1147 typedef struct stackinfo PERL_SI;
1148
1149 #define cxstack         (PL_curstackinfo->si_cxstack)
1150 #define cxstack_ix      (PL_curstackinfo->si_cxix)
1151 #define cxstack_max     (PL_curstackinfo->si_cxmax)
1152
1153 #ifdef DEBUGGING
1154 #  define       SET_MARK_OFFSET \
1155     PL_curstackinfo->si_markoff = PL_markstack_ptr - PL_markstack
1156 #else
1157 #  define       SET_MARK_OFFSET NOOP
1158 #endif
1159
1160 #define PUSHSTACKi(type) \
1161     STMT_START {                                                        \
1162         PERL_SI *next = PL_curstackinfo->si_next;                       \
1163         DEBUG_l({                                                       \
1164             int i = 0; PERL_SI *p = PL_curstackinfo;                    \
1165             while (p) { i++; p = p->si_prev; }                          \
1166             Perl_deb(aTHX_ "push STACKINFO %d at %s:%d\n",              \
1167                          i, __FILE__, __LINE__);})                      \
1168         if (!next) {                                                    \
1169             next = new_stackinfo(32, 2048/sizeof(PERL_CONTEXT) - 1);    \
1170             next->si_prev = PL_curstackinfo;                            \
1171             PL_curstackinfo->si_next = next;                            \
1172         }                                                               \
1173         next->si_type = type;                                           \
1174         next->si_cxix = -1;                                             \
1175         AvFILLp(next->si_stack) = 0;                                    \
1176         SWITCHSTACK(PL_curstack,next->si_stack);                        \
1177         PL_curstackinfo = next;                                         \
1178         SET_MARK_OFFSET;                                                \
1179     } STMT_END
1180
1181 #define PUSHSTACK PUSHSTACKi(PERLSI_UNKNOWN)
1182
1183 /* POPSTACK works with PL_stack_sp, so it may need to be bracketed by
1184  * PUTBACK/SPAGAIN to flush/refresh any local SP that may be active */
1185 #define POPSTACK \
1186     STMT_START {                                                        \
1187         dSP;                                                            \
1188         PERL_SI * const prev = PL_curstackinfo->si_prev;                \
1189         DEBUG_l({                                                       \
1190             int i = -1; PERL_SI *p = PL_curstackinfo;                   \
1191             while (p) { i++; p = p->si_prev; }                          \
1192             Perl_deb(aTHX_ "pop  STACKINFO %d at %s:%d\n",              \
1193                          i, __FILE__, __LINE__);})                      \
1194         if (!prev) {                                                    \
1195             Perl_croak_popstack();                                      \
1196         }                                                               \
1197         SWITCHSTACK(PL_curstack,prev->si_stack);                        \
1198         /* don't free prev here, free them all at the END{} */          \
1199         PL_curstackinfo = prev;                                         \
1200     } STMT_END
1201
1202 #define POPSTACK_TO(s) \
1203     STMT_START {                                                        \
1204         while (PL_curstack != s) {                                      \
1205             dounwind(-1);                                               \
1206             POPSTACK;                                                   \
1207         }                                                               \
1208     } STMT_END
1209
1210 #define IN_PERL_COMPILETIME     (PL_curcop == &PL_compiling)
1211 #define IN_PERL_RUNTIME         (PL_curcop != &PL_compiling)
1212
1213 /*
1214 =head1 Multicall Functions
1215
1216 =for apidoc Ams||dMULTICALL
1217 Declare local variables for a multicall.  See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1218
1219 =for apidoc Ams||PUSH_MULTICALL
1220 Opening bracket for a lightweight callback.
1221 See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1222
1223 =for apidoc Ams||MULTICALL
1224 Make a lightweight callback.  See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1225
1226 =for apidoc Ams||POP_MULTICALL
1227 Closing bracket for a lightweight callback.
1228 See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1229
1230 =cut
1231 */
1232
1233 #define dMULTICALL \
1234     SV **newsp;                 /* set by POPBLOCK */                   \
1235     PERL_CONTEXT *cx;                                                   \
1236     CV *multicall_cv;                                                   \
1237     OP *multicall_cop;                                                  \
1238     bool multicall_oldcatch;                                            \
1239     U8 hasargs = 0              /* used by PUSHSUB */
1240
1241 #define PUSH_MULTICALL(the_cv) \
1242     PUSH_MULTICALL_FLAGS(the_cv, 0)
1243
1244 /* Like PUSH_MULTICALL, but allows you to specify extra flags
1245  * for the CX stack entry (this isn't part of the public API) */
1246
1247 #define PUSH_MULTICALL_FLAGS(the_cv, flags) \
1248     STMT_START {                                                        \
1249         CV * const _nOnclAshIngNamE_ = the_cv;                          \
1250         CV * const cv = _nOnclAshIngNamE_;                              \
1251         PADLIST * const padlist = CvPADLIST(cv);                        \
1252         multicall_oldcatch = CATCH_GET;                                 \
1253         CATCH_SET(TRUE);                                                \
1254         PUSHSTACKi(PERLSI_MULTICALL);                                   \
1255         PUSHBLOCK(cx, (CXt_SUB|CXp_MULTICALL|flags), PL_stack_sp);      \
1256         PUSHSUB(cx);                                                    \
1257         cx->cx_u.cx_blk.blku_old_savestack_ix = PL_savestack_ix;        \
1258         SAVEVPTR(PL_op);                                                \
1259         if (!(flags & CXp_SUB_RE_FAKE))                                 \
1260             CvDEPTH(cv)++;                                              \
1261         if (CvDEPTH(cv) >= 2) {                                         \
1262             PERL_STACK_OVERFLOW_CHECK();                                \
1263             Perl_pad_push(aTHX_ padlist, CvDEPTH(cv));                  \
1264         }                                                               \
1265         PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));                       \
1266         multicall_cv = cv;                                              \
1267         multicall_cop = CvSTART(cv);                                    \
1268     } STMT_END
1269
1270 #define MULTICALL \
1271     STMT_START {                                                        \
1272         PL_op = multicall_cop;                                          \
1273         CALLRUNOPS(aTHX);                                               \
1274     } STMT_END
1275
1276 #define POP_MULTICALL \
1277     STMT_START {                                                        \
1278         cx = &cxstack[cxstack_ix];                                      \
1279         CvDEPTH(multicall_cv) = cx->blk_sub.olddepth;                   \
1280         LEAVESUB(multicall_cv);                                         \
1281         POPBLOCK(cx,PL_curpm);                                          \
1282         /* includes partial unrolled POPSUB(): */                       \
1283         LEAVE_SCOPE(cx->cx_u.cx_blk.blku_old_savestack_ix);             \
1284         PL_comppad = cx->blk_sub.prevcomppad;                           \
1285         PL_curpad = LIKELY(PL_comppad) ? AvARRAY(PL_comppad) : NULL;    \
1286         POPSTACK;                                                       \
1287         CATCH_SET(multicall_oldcatch);                                  \
1288         SPAGAIN;                                                        \
1289     } STMT_END
1290
1291 /* Change the CV of an already-pushed MULTICALL CxSUB block.
1292  * (this isn't part of the public API) */
1293
1294 #define CHANGE_MULTICALL_FLAGS(the_cv, flags) \
1295     STMT_START {                                                        \
1296         CV * const _nOnclAshIngNamE_ = the_cv;                          \
1297         CV * const cv = _nOnclAshIngNamE_;                              \
1298         PADLIST * const padlist = CvPADLIST(cv);                        \
1299         cx = &cxstack[cxstack_ix];                                      \
1300         assert(cx->cx_type & CXp_MULTICALL);                            \
1301         CvDEPTH(multicall_cv) = cx->blk_sub.olddepth;                   \
1302         LEAVESUB(multicall_cv);                                         \
1303         cx->cx_type = (CXt_SUB|CXp_MULTICALL|flags);                    \
1304         {                                                               \
1305             /* save a few things that we don't want PUSHSUB to zap */   \
1306             PAD * const prevcomppad = cx->blk_sub.prevcomppad;          \
1307             SSize_t old_floor = cx->cx_u.cx_blk.blku_old_tmpsfloor;     \
1308             SSize_t floor = PL_tmps_floor;                              \
1309             PUSHSUB(cx);                                                \
1310             /* undo the stuff that PUSHSUB zapped */                    \
1311             cx->blk_sub.prevcomppad = prevcomppad ;                     \
1312             cx->cx_u.cx_blk.blku_old_tmpsfloor = old_floor;             \
1313             PL_tmps_floor = floor;                                      \
1314         }                                                               \
1315         if (!(flags & CXp_SUB_RE_FAKE))                                 \
1316             CvDEPTH(cv)++;                                              \
1317         if (CvDEPTH(cv) >= 2) {                                         \
1318             PERL_STACK_OVERFLOW_CHECK();                                \
1319             Perl_pad_push(aTHX_ padlist, CvDEPTH(cv));                  \
1320         }                                                               \
1321         PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));                       \
1322         multicall_cv = cv;                                              \
1323         multicall_cop = CvSTART(cv);                                    \
1324     } STMT_END
1325 /*
1326  * ex: set ts=8 sts=4 sw=4 et:
1327  */