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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 /* free all savestack items back to the watermark of the specified context */
574
575 #define CX_LEAVE_SCOPE(cx) \
576     LEAVE_SCOPE(cx->cx_u.cx_blk.blku_old_savestack_ix)
577
578 /* base for the next two macros. Don't use directly.
579  * The context frame holds a reference to the CV so that it can't be
580  * freed while we're executing it */
581
582 #define PUSHSUB_BASE(cx)                                                \
583         ENTRY_PROBE(CvNAMED(cv)                                         \
584                         ? HEK_KEY(CvNAME_HEK(cv))                       \
585                         : GvENAME(CvGV(cv)),                            \
586                 CopFILE((const COP *)CvSTART(cv)),                      \
587                 CopLINE((const COP *)CvSTART(cv)),                      \
588                 CopSTASHPV((const COP *)CvSTART(cv)));                  \
589                                                                         \
590         cx->blk_sub.cv = cv;                                            \
591         cx->blk_sub.olddepth = CvDEPTH(cv);                             \
592         cx->blk_sub.prevcomppad = PL_comppad;                           \
593         cx->cx_type |= (hasargs) ? CXp_HASARGS : 0;                     \
594         cx->blk_sub.retop = NULL;                                       \
595         SvREFCNT_inc_simple_void_NN(cv);
596
597 #define PUSHSUB_GET_LVALUE_MASK(func) \
598         /* If the context is indeterminate, then only the lvalue */     \
599         /* flags that the caller also has are applicable.        */     \
600         (                                                               \
601            (PL_op->op_flags & OPf_WANT)                                 \
602                ? OPpENTERSUB_LVAL_MASK                                  \
603                : !(PL_op->op_private & OPpENTERSUB_LVAL_MASK)           \
604                    ? 0 : (U8)func(aTHX)                                 \
605         )
606
607 #define PUSHSUB(cx)                                                     \
608     {                                                                   \
609         U8 phlags = PUSHSUB_GET_LVALUE_MASK(Perl_was_lvalue_sub);       \
610         PUSHSUB_BASE(cx)                                                \
611         cx->blk_u16 = PL_op->op_private &                               \
612                           (phlags|OPpDEREF);                            \
613     }
614
615 /* variant for use by OP_DBSTATE, where op_private holds hint bits */
616 #define PUSHSUB_DB(cx)                                                  \
617         PUSHSUB_BASE(cx)                                                \
618         cx->blk_u16 = 0;
619
620
621 #define PUSHFORMAT(cx, retop)                                           \
622         cx->blk_format.cv = cv;                                         \
623         cx->blk_format.gv = gv;                                         \
624         cx->blk_format.retop = (retop);                                 \
625         cx->blk_format.dfoutgv = PL_defoutgv;                           \
626         cx->blk_format.prevcomppad = PL_comppad;                        \
627         cx->blk_u16 = 0;                                                \
628         cx->cx_u.cx_blk.blku_old_savestack_ix = PL_savestack_ix;        \
629         SvREFCNT_inc_simple_void_NN(cv);                                \
630         CvDEPTH(cv)++;                                                  \
631         SvREFCNT_inc_void(cx->blk_format.dfoutgv)
632
633 /* Restore old @_ */
634 #define POP_SAVEARRAY()                                         \
635     STMT_START {                                                        \
636         AV *av = GvAV(PL_defgv);                                        \
637         GvAV(PL_defgv) = cx->blk_sub.savearray;                         \
638         SvREFCNT_dec(av);                                               \
639     } STMT_END
640
641 /* junk in @_ spells trouble when cloning CVs and in pp_caller(), so don't
642  * leave any (a fast av_clear(ary), basically) */
643 #define CLEAR_ARGARRAY(ary) \
644     STMT_START {                                                        \
645         AvMAX(ary) += AvARRAY(ary) - AvALLOC(ary);                      \
646         AvARRAY(ary) = AvALLOC(ary);                                    \
647         AvFILLp(ary) = -1;                                              \
648     } STMT_END
649
650 #define POPSUB(cx)                                                      \
651     STMT_START {                                                        \
652         CX_LEAVE_SCOPE(cx);                                             \
653         if (!(cx->blk_u16 & CxPOPSUB_DONE)) {                           \
654         cx->blk_u16 |= CxPOPSUB_DONE;                                   \
655         RETURN_PROBE(CvNAMED(cx->blk_sub.cv)                            \
656                         ? HEK_KEY(CvNAME_HEK(cx->blk_sub.cv))           \
657                         : GvENAME(CvGV(cx->blk_sub.cv)),                \
658                 CopFILE((COP*)CvSTART((const CV*)cx->blk_sub.cv)),      \
659                 CopLINE((COP*)CvSTART((const CV*)cx->blk_sub.cv)),      \
660                 CopSTASHPV((COP*)CvSTART((const CV*)cx->blk_sub.cv)));  \
661                                                                         \
662         if (CxHASARGS(cx)) {                                            \
663             AV *av;                                                     \
664             assert(AvARRAY(MUTABLE_AV(                                  \
665                 PadlistARRAY(CvPADLIST(cx->blk_sub.cv))[                \
666                         CvDEPTH(cx->blk_sub.cv)])) == PL_curpad);       \
667             POP_SAVEARRAY();                                            \
668             /* abandon @_ if it got reified */                          \
669             av = MUTABLE_AV(PAD_SVl(0));                                \
670             if (UNLIKELY(AvREAL(av)))                                   \
671                 clear_defarray(av, 0);                                  \
672             else {                                                      \
673                 CLEAR_ARGARRAY(av);                                     \
674             }                                                           \
675         }                                                               \
676         }                                                               \
677         PL_comppad = cx->blk_sub.prevcomppad;                           \
678         PL_curpad = LIKELY(PL_comppad) ? AvARRAY(PL_comppad) : NULL;    \
679         CvDEPTH((const CV*)cx->blk_sub.cv) = cx->blk_sub.olddepth;      \
680         SvREFCNT_dec_NN(cx->blk_sub.cv);                                \
681     } STMT_END
682
683 #define POPFORMAT(cx)                                                   \
684     STMT_START {                                                        \
685         CX_LEAVE_SCOPE(cx);                                             \
686         if (!(cx->blk_u16 & CxPOPSUB_DONE)) {                           \
687         CV * const cv = cx->blk_format.cv;                              \
688         GV * const dfuot = cx->blk_format.dfoutgv;                      \
689         cx->blk_u16 |= CxPOPSUB_DONE;                                   \
690         setdefout(dfuot);                                               \
691         PL_comppad = cx->blk_format.prevcomppad;                        \
692         PL_curpad = LIKELY(PL_comppad) ? AvARRAY(PL_comppad) : NULL;    \
693         --CvDEPTH(cv);                                                  \
694         SvREFCNT_dec_NN(cx->blk_format.cv);                             \
695         SvREFCNT_dec_NN(dfuot);                                         \
696         }                                                               \
697     } STMT_END
698
699 /* eval context */
700 struct block_eval {
701     OP *        retop;  /* op to execute on exit from eval */
702     /* Above here is the same for sub, format and eval.  */
703     SV *        old_namesv;
704     OP *        old_eval_root;
705     SV *        cur_text;
706     CV *        cv;
707     JMPENV *    cur_top_env; /* value of PL_top_env when eval CX created */
708 };
709
710 /* If we ever need more than 512 op types, change the shift from 7.
711    blku_gimme is actually also only 2 bits, so could be merged with something.
712 */
713
714 #define CxOLD_IN_EVAL(cx)       (((cx)->blk_u16) & 0x7F)
715 #define CxOLD_OP_TYPE(cx)       (((cx)->blk_u16) >> 7)
716
717 #define PUSHEVAL(cx,n)                                                  \
718     STMT_START {                                                        \
719         assert(!(PL_in_eval & ~0x7F));                                  \
720         assert(!(PL_op->op_type & ~0x1FF));                             \
721         cx->blk_u16 = (PL_in_eval & 0x7F) | ((U16)PL_op->op_type << 7); \
722         cx->blk_eval.old_namesv = (n ? newSVpv(n,0) : NULL);            \
723         cx->blk_eval.old_eval_root = PL_eval_root;                      \
724         cx->blk_eval.cur_text = PL_parser ? PL_parser->linestr : NULL;  \
725         cx->blk_eval.cv = NULL; /* set by doeval(), as applicable */    \
726         cx->blk_eval.retop = NULL;                                      \
727         cx->blk_eval.cur_top_env = PL_top_env;                          \
728     } STMT_END
729
730 #define POPEVAL(cx)                                                     \
731     STMT_START {                                                        \
732         CX_LEAVE_SCOPE(cx);                                             \
733         PL_in_eval = CxOLD_IN_EVAL(cx);                                 \
734         optype = CxOLD_OP_TYPE(cx);                                     \
735         PL_eval_root = cx->blk_eval.old_eval_root;                      \
736         if (cx->blk_eval.cur_text && SvSCREAM(cx->blk_eval.cur_text))   \
737             SvREFCNT_dec_NN(cx->blk_eval.cur_text);                     \
738         if (cx->blk_eval.old_namesv)                                    \
739             sv_2mortal(cx->blk_eval.old_namesv);                        \
740     } STMT_END
741
742 /* loop context */
743 struct block_loop {
744     I32         resetsp;
745     LOOP *      my_op;  /* My op, that contains redo, next and last ops.  */
746     union {     /* different ways of locating the iteration variable */
747         SV      **svp; /* for lexicals: address of pad slot */
748         GV      *gv;   /* for package vars */
749     } itervar_u;
750     SV          *itersave; /* the original iteration var */
751     union {
752         struct { /* valid if type is LOOP_FOR or LOOP_PLAIN (but {NULL,0})*/
753             AV * ary; /* use the stack if this is NULL */
754             IV ix;
755         } ary;
756         struct { /* valid if type is LOOP_LAZYIV */
757             IV cur;
758             IV end;
759         } lazyiv;
760         struct { /* valid if type if LOOP_LAZYSV */
761             SV * cur;
762             SV * end; /* maxiumum value (or minimum in reverse) */
763         } lazysv;
764     } state_u;
765 #ifdef USE_ITHREADS
766     PAD *oldcomppad; /* needed to map itervar_u.svp during thread clone */
767 #endif
768 };
769
770 #define CxITERVAR(c)                                    \
771         (CxPADLOOP(c)                                   \
772             ? (c)->blk_loop.itervar_u.svp               \
773             : ((c)->cx_type & CXp_FOR_GV)               \
774                 ? &GvSV((c)->blk_loop.itervar_u.gv)     \
775                 : (SV **)&(c)->blk_loop.itervar_u.gv)
776
777 #define CxLABEL(c)      (0 + CopLABEL((c)->blk_oldcop))
778 #define CxLABEL_len(c,len)      (0 + CopLABEL_len((c)->blk_oldcop, len))
779 #define CxLABEL_len_flags(c,len,flags)  (0 + CopLABEL_len_flags((c)->blk_oldcop, len, flags))
780 #define CxHASARGS(c)    (((c)->cx_type & CXp_HASARGS) == CXp_HASARGS)
781 #define CxLVAL(c)       (0 + ((c)->blk_u16 & 0xff))
782 /* POPSUB has already been performed on this context frame */
783 #define CxPOPSUB_DONE 0x100
784
785
786 #define PUSHLOOP_PLAIN(cx, s)                                           \
787         cx->blk_loop.resetsp = s - PL_stack_base;                       \
788         cx->blk_loop.my_op = cLOOP;                                     \
789         cx->blk_loop.state_u.ary.ary = NULL;                            \
790         cx->blk_loop.state_u.ary.ix = 0;                                \
791         cx->cx_u.cx_blk.blku_old_savestack_ix = PL_savestack_ix;        \
792         cx->blk_loop.itervar_u.svp = NULL;                              \
793         cx->blk_loop.itersave = NULL;
794
795 #ifdef USE_ITHREADS
796 #  define PUSHLOOP_FOR_setpad(c) (c)->blk_loop.oldcomppad = PL_comppad
797 #else
798 #  define PUSHLOOP_FOR_setpad(c) NOOP
799 #endif
800
801 #define PUSHLOOP_FOR(cx, ivar, isave, s)                                \
802         cx->blk_loop.resetsp = s - PL_stack_base;                       \
803         cx->blk_loop.my_op = cLOOP;                                     \
804         cx->blk_loop.state_u.ary.ary = NULL;                            \
805         cx->blk_loop.state_u.ary.ix = 0;                                \
806         cx->blk_loop.itervar_u.svp = (SV**)(ivar);                      \
807         cx->cx_u.cx_blk.blku_old_savestack_ix = PL_savestack_ix;        \
808         cx->blk_loop.itersave = isave;                                  \
809         PUSHLOOP_FOR_setpad(cx);
810
811 #define POPLOOP(cx)                                                     \
812         CX_LEAVE_SCOPE(cx);                                             \
813         if (CxTYPE(cx) == CXt_LOOP_LAZYSV) {                            \
814             SvREFCNT_dec_NN(cx->blk_loop.state_u.lazysv.cur);           \
815             SvREFCNT_dec_NN(cx->blk_loop.state_u.lazysv.end);           \
816         }                                                               \
817         else if (CxTYPE(cx) == CXt_LOOP_FOR)                            \
818             SvREFCNT_dec(cx->blk_loop.state_u.ary.ary);                 \
819         if (cx->cx_type & (CXp_FOR_PAD|CXp_FOR_GV)) {                   \
820             SV *cursv;                                                  \
821             SV **svp = (cx)->blk_loop.itervar_u.svp;                    \
822             if ((cx->cx_type & CXp_FOR_GV))                             \
823                 svp = &GvSV((GV*)svp);                                  \
824             cursv = *svp;                                               \
825             *svp = cx->blk_loop.itersave;                               \
826             SvREFCNT_dec(cursv);                                        \
827         }
828
829 /* given/when context */
830 struct block_givwhen {
831         OP *leave_op;
832         SV *defsv_save; /* the original $_ */
833 };
834
835 #define PUSHWHEN(cx)                                                    \
836         cx->cx_u.cx_blk.blku_old_savestack_ix = PL_savestack_ix;        \
837         cx->blk_givwhen.leave_op = cLOGOP->op_other;
838
839 #define PUSHGIVEN(cx, orig_var)                                         \
840         PUSHWHEN(cx);                                                   \
841         cx->blk_givwhen.defsv_save = orig_var;
842
843 #define POPWHEN(cx)                                                     \
844         CX_LEAVE_SCOPE(cx);
845
846 #define POPGIVEN(cx)                                                    \
847         CX_LEAVE_SCOPE(cx);                                             \
848         SvREFCNT_dec(GvSV(PL_defgv));                                   \
849         GvSV(PL_defgv) = cx->blk_givwhen.defsv_save;
850
851
852 /* basic block, i.e. pp_enter/leave */
853
854 #define PUSHBASICBLK(cx)                                                \
855         cx->cx_u.cx_blk.blku_old_savestack_ix = PL_savestack_ix;
856
857 #define POPBASICBLK(cx)                                                 \
858         CX_LEAVE_SCOPE(cx);
859
860
861 /* context common to subroutines, evals and loops */
862 struct block {
863     U8          blku_type;      /* what kind of context this is */
864     U8          blku_gimme;     /* is this block running in list context? */
865     U16         blku_u16;       /* used by block_sub and block_eval (so far) */
866     I32         blku_oldsp;     /* stack pointer to copy stuff down to */
867     COP *       blku_oldcop;    /* old curcop pointer */
868     I32         blku_oldmarksp; /* mark stack index */
869     I32         blku_oldscopesp;        /* scope stack index */
870     PMOP *      blku_oldpm;     /* values of pattern match vars */
871     SSize_t     blku_old_tmpsfloor;     /* saved PL_tmps_floor */
872     I32         blku_old_savestack_ix;  /* saved PL_savestack_ix */
873
874     union {
875         struct block_sub        blku_sub;
876         struct block_format     blku_format;
877         struct block_eval       blku_eval;
878         struct block_loop       blku_loop;
879         struct block_givwhen    blku_givwhen;
880     } blk_u;
881 };
882 #define blk_oldsp       cx_u.cx_blk.blku_oldsp
883 #define blk_oldcop      cx_u.cx_blk.blku_oldcop
884 #define blk_oldmarksp   cx_u.cx_blk.blku_oldmarksp
885 #define blk_oldscopesp  cx_u.cx_blk.blku_oldscopesp
886 #define blk_oldpm       cx_u.cx_blk.blku_oldpm
887 #define blk_gimme       cx_u.cx_blk.blku_gimme
888 #define blk_u16         cx_u.cx_blk.blku_u16
889 #define blk_sub         cx_u.cx_blk.blk_u.blku_sub
890 #define blk_format      cx_u.cx_blk.blk_u.blku_format
891 #define blk_eval        cx_u.cx_blk.blk_u.blku_eval
892 #define blk_loop        cx_u.cx_blk.blk_u.blku_loop
893 #define blk_givwhen     cx_u.cx_blk.blk_u.blku_givwhen
894
895 #define DEBUG_CX(action)                                                \
896     DEBUG_l(                                                            \
897         Perl_deb(aTHX_ "CX %ld %s %s (scope %ld,%ld) (save %ld,%ld) at %s:%d\n",\
898                     (long)cxstack_ix,                                   \
899                     action,                                             \
900                     PL_block_type[CxTYPE(&cxstack[cxstack_ix])],        \
901                     (long)PL_scopestack_ix,                             \
902                     (long)(cxstack[cxstack_ix].blk_oldscopesp),         \
903                     (long)PL_savestack_ix,                              \
904                     (long)(cxstack[cxstack_ix].cx_u.cx_blk.blku_old_savestack_ix),\
905                     __FILE__, __LINE__));
906
907 /* Enter a block. */
908 #define PUSHBLOCK(cx,t,sp) CXINC, cx = &cxstack[cxstack_ix],            \
909         cx->cx_type             = t,                                    \
910         cx->blk_oldsp           = sp - PL_stack_base,                   \
911         cx->blk_oldcop          = PL_curcop,                            \
912         cx->blk_oldmarksp       = PL_markstack_ptr - PL_markstack,      \
913         cx->blk_oldscopesp      = PL_scopestack_ix,                     \
914         cx->blk_oldpm           = PL_curpm,                             \
915         cx->blk_gimme           = (U8)gimme;                            \
916         cx->cx_u.cx_blk.blku_old_tmpsfloor = PL_tmps_floor;             \
917         PL_tmps_floor           = PL_tmps_ix;                           \
918         DEBUG_CX("PUSH");
919
920 /* Exit a block (RETURN and LAST). */
921 #define POPBLOCK(cx)                                                    \
922         DEBUG_CX("POP");                                                \
923         PL_curcop        = cx->blk_oldcop,                              \
924         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
925         PL_scopestack_ix = cx->blk_oldscopesp,                          \
926         /* LEAVE_SCOPE() should have made this true. /(?{})/ cheats
927          * and leaves a CX entry lying around for repeated use, so
928          * skip for multicall */                  \
929         assert((CxTYPE(cx) == CXt_SUB && CxMULTICALL(cx)) ||            \
930             PL_savestack_ix == cx->cx_u.cx_blk.blku_old_savestack_ix);  \
931         PL_tmps_floor = cx->cx_u.cx_blk.blku_old_tmpsfloor;             \
932         PL_curpm         = cx->blk_oldpm;
933
934 /* Continue a block elsewhere (NEXT and REDO). */
935 #define TOPBLOCK(cx)                                                    \
936         DEBUG_CX("TOP");                                                \
937         cx  = &cxstack[cxstack_ix],                                     \
938         PL_stack_sp      = PL_stack_base + cx->blk_oldsp,               \
939         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
940         PL_scopestack_ix = cx->blk_oldscopesp,                          \
941         PL_curpm         = cx->blk_oldpm;
942
943 /* substitution context */
944 struct subst {
945     U8          sbu_type;       /* what kind of context this is */
946     U8          sbu_rflags;
947     U16         sbu_rxtainted;  /* matches struct block */
948     I32         sbu_oldsave;
949     SSize_t     sbu_iters;
950     SSize_t     sbu_maxiters;
951     char *      sbu_orig;
952     SV *        sbu_dstr;
953     SV *        sbu_targ;
954     char *      sbu_s;
955     char *      sbu_m;
956     char *      sbu_strend;
957     void *      sbu_rxres;
958     REGEXP *    sbu_rx;
959 };
960 #define sb_iters        cx_u.cx_subst.sbu_iters
961 #define sb_maxiters     cx_u.cx_subst.sbu_maxiters
962 #define sb_rflags       cx_u.cx_subst.sbu_rflags
963 #define sb_oldsave      cx_u.cx_subst.sbu_oldsave
964 #define sb_rxtainted    cx_u.cx_subst.sbu_rxtainted
965 #define sb_orig         cx_u.cx_subst.sbu_orig
966 #define sb_dstr         cx_u.cx_subst.sbu_dstr
967 #define sb_targ         cx_u.cx_subst.sbu_targ
968 #define sb_s            cx_u.cx_subst.sbu_s
969 #define sb_m            cx_u.cx_subst.sbu_m
970 #define sb_strend       cx_u.cx_subst.sbu_strend
971 #define sb_rxres        cx_u.cx_subst.sbu_rxres
972 #define sb_rx           cx_u.cx_subst.sbu_rx
973
974 #ifdef PERL_CORE
975 #  define PUSHSUBST(cx) CXINC, cx = &cxstack[cxstack_ix],               \
976         cx->sb_iters            = iters,                                \
977         cx->sb_maxiters         = maxiters,                             \
978         cx->sb_rflags           = r_flags,                              \
979         cx->sb_oldsave          = oldsave,                              \
980         cx->sb_rxtainted        = rxtainted,                            \
981         cx->sb_orig             = orig,                                 \
982         cx->sb_dstr             = dstr,                                 \
983         cx->sb_targ             = targ,                                 \
984         cx->sb_s                = s,                                    \
985         cx->sb_m                = m,                                    \
986         cx->sb_strend           = strend,                               \
987         cx->sb_rxres            = NULL,                                 \
988         cx->sb_rx               = rx,                                   \
989         cx->cx_type             = CXt_SUBST | (once ? CXp_ONCE : 0);    \
990         rxres_save(&cx->sb_rxres, rx);                                  \
991         (void)ReREFCNT_inc(rx);                                         \
992         SvREFCNT_inc_void_NN(targ)
993
994 #  define POPSUBST(cx) cx = &cxstack[cxstack_ix--];                     \
995         rxres_free(&cx->sb_rxres);                                      \
996         ReREFCNT_dec(cx->sb_rx);                                        \
997         SvREFCNT_dec_NN(cx->sb_targ)
998 #endif
999
1000 #define CxONCE(cx)              ((cx)->cx_type & CXp_ONCE)
1001
1002 struct context {
1003     union {
1004         struct block    cx_blk;
1005         struct subst    cx_subst;
1006     } cx_u;
1007 };
1008 #define cx_type cx_u.cx_subst.sbu_type
1009
1010 /* If you re-order these, there is also an array of uppercase names in perl.h
1011    and a static array of context names in pp_ctl.c  */
1012 #define CXTYPEMASK      0xf
1013 #define CXt_NULL        0 /* currently only used for sort BLOCK */
1014 #define CXt_WHEN        1
1015 #define CXt_BLOCK       2
1016 /* When micro-optimising :-) keep GIVEN next to the LOOPs, as these 5 share a
1017    jump table in pp_ctl.c
1018    The first 4 don't have a 'case' in at least one switch statement in pp_ctl.c
1019 */
1020 #define CXt_GIVEN       3
1021 /* This is first so that CXt_LOOP_FOR|CXt_LOOP_LAZYIV is CXt_LOOP_LAZYIV */
1022 #define CXt_LOOP_FOR    4
1023 #define CXt_LOOP_PLAIN  5
1024 #define CXt_LOOP_LAZYSV 6
1025 #define CXt_LOOP_LAZYIV 7
1026 #define CXt_SUB         8
1027 #define CXt_FORMAT      9
1028 #define CXt_EVAL       10
1029 #define CXt_SUBST      11
1030 /* SUBST doesn't feature in all switch statements.  */
1031
1032 /* private flags for CXt_SUB and CXt_FORMAT */
1033 #define CXp_MULTICALL   0x10    /* part of a multicall (so don't tear down
1034                                    context on exit). (not CXt_FORMAT) */
1035 #define CXp_HASARGS     0x20
1036 #define CXp_SUB_RE      0x40    /* code called within regex, i.e. (?{}) */
1037 #define CXp_SUB_RE_FAKE 0x80    /* fake sub CX for (?{}) in current scope */
1038
1039 /* private flags for CXt_EVAL */
1040 #define CXp_REAL        0x20    /* truly eval'', not a lookalike */
1041 #define CXp_TRYBLOCK    0x40    /* eval{}, not eval'' or similar */
1042
1043 /* private flags for CXt_LOOP */
1044 #define CXp_FOR_DEF     0x10    /* foreach using $_ */
1045 #define CXp_FOR_LVREF   0x20    /* foreach using \$var */
1046 #define CXp_FOR_GV      0x40    /* foreach using package var */
1047 #define CXp_FOR_PAD     0x80    /* foreach using lexical var */
1048 #define CxPADLOOP(c)    ((c)->cx_type & CXp_FOR_PAD)
1049
1050 /* private flags for CXt_SUBST */
1051 #define CXp_ONCE        0x10    /* What was sbu_once in struct subst */
1052
1053 #define CxTYPE(c)       ((c)->cx_type & CXTYPEMASK)
1054 #define CxTYPE_is_LOOP(c)       (((c)->cx_type & 0xC) == 0x4)
1055 #define CxMULTICALL(c)  ((c)->cx_type & CXp_MULTICALL)
1056 #define CxREALEVAL(c)   (((c)->cx_type & (CXTYPEMASK|CXp_REAL))         \
1057                          == (CXt_EVAL|CXp_REAL))
1058 #define CxTRYBLOCK(c)   (((c)->cx_type & (CXTYPEMASK|CXp_TRYBLOCK))     \
1059                          == (CXt_EVAL|CXp_TRYBLOCK))
1060 #define CxFOREACH(c)    (CxTYPE_is_LOOP(c) && CxTYPE(c) != CXt_LOOP_PLAIN)
1061 #define CxFOREACHDEF(c) ((CxTYPE_is_LOOP(c) && CxTYPE(c) != CXt_LOOP_PLAIN) \
1062                          && ((c)->cx_type & CXp_FOR_DEF))
1063
1064 #define CXINC (cxstack_ix < cxstack_max ? ++cxstack_ix : (cxstack_ix = cxinc()))
1065
1066 /* 
1067 =head1 "Gimme" Values
1068 */
1069
1070 /*
1071 =for apidoc AmU||G_SCALAR
1072 Used to indicate scalar context.  See C<L</GIMME_V>>, C<L</GIMME>>, and
1073 L<perlcall>.
1074
1075 =for apidoc AmU||G_ARRAY
1076 Used to indicate list context.  See C<L</GIMME_V>>, C<L</GIMME>> and
1077 L<perlcall>.
1078
1079 =for apidoc AmU||G_VOID
1080 Used to indicate void context.  See C<L</GIMME_V>> and L<perlcall>.
1081
1082 =for apidoc AmU||G_DISCARD
1083 Indicates that arguments returned from a callback should be discarded.  See
1084 L<perlcall>.
1085
1086 =for apidoc AmU||G_EVAL
1087
1088 Used to force a Perl C<eval> wrapper around a callback.  See
1089 L<perlcall>.
1090
1091 =for apidoc AmU||G_NOARGS
1092
1093 Indicates that no arguments are being sent to a callback.  See
1094 L<perlcall>.
1095
1096 =cut
1097 */
1098
1099 #define G_SCALAR        2
1100 #define G_ARRAY         3
1101 #define G_VOID          1
1102 #define G_WANT          3
1103
1104 /* extra flags for Perl_call_* routines */
1105 #define G_DISCARD       4       /* Call FREETMPS.
1106                                    Don't change this without consulting the
1107                                    hash actions codes defined in hv.h */
1108 #define G_EVAL          8       /* Assume eval {} around subroutine call. */
1109 #define G_NOARGS       16       /* Don't construct a @_ array. */
1110 #define G_KEEPERR      32       /* Warn for errors, don't overwrite $@ */
1111 #define G_NODEBUG      64       /* Disable debugging at toplevel.  */
1112 #define G_METHOD      128       /* Calling method. */
1113 #define G_FAKINGEVAL  256       /* Faking an eval context for call_sv or
1114                                    fold_constants. */
1115 #define G_UNDEF_FILL  512       /* Fill the stack with &PL_sv_undef
1116                                    A special case for UNSHIFT in
1117                                    Perl_magic_methcall().  */
1118 #define G_WRITING_TO_STDERR 1024 /* Perl_write_to_stderr() is calling
1119                                     Perl_magic_methcall().  */
1120 #define G_RE_REPARSING 0x800     /* compiling a run-time /(?{..})/ */
1121 #define G_METHOD_NAMED 4096     /* calling named method, eg without :: or ' */
1122
1123 /* flag bits for PL_in_eval */
1124 #define EVAL_NULL       0       /* not in an eval */
1125 #define EVAL_INEVAL     1       /* some enclosing scope is an eval */
1126 #define EVAL_WARNONLY   2       /* used by yywarn() when calling yyerror() */
1127 #define EVAL_KEEPERR    4       /* set by Perl_call_sv if G_KEEPERR */
1128 #define EVAL_INREQUIRE  8       /* The code is being required. */
1129 #define EVAL_RE_REPARSING 0x10  /* eval_sv() called with G_RE_REPARSING */
1130
1131 /* Support for switching (stack and block) contexts.
1132  * This ensures magic doesn't invalidate local stack and cx pointers.
1133  */
1134
1135 #define PERLSI_UNKNOWN          -1
1136 #define PERLSI_UNDEF            0
1137 #define PERLSI_MAIN             1
1138 #define PERLSI_MAGIC            2
1139 #define PERLSI_SORT             3
1140 #define PERLSI_SIGNAL           4
1141 #define PERLSI_OVERLOAD         5
1142 #define PERLSI_DESTROY          6
1143 #define PERLSI_WARNHOOK         7
1144 #define PERLSI_DIEHOOK          8
1145 #define PERLSI_REQUIRE          9
1146 #define PERLSI_MULTICALL       10
1147
1148 struct stackinfo {
1149     AV *                si_stack;       /* stack for current runlevel */
1150     PERL_CONTEXT *      si_cxstack;     /* context stack for runlevel */
1151     struct stackinfo *  si_prev;
1152     struct stackinfo *  si_next;
1153     I32                 si_cxix;        /* current context index */
1154     I32                 si_cxmax;       /* maximum allocated index */
1155     I32                 si_type;        /* type of runlevel */
1156     I32                 si_markoff;     /* offset where markstack begins for us.
1157                                          * currently used only with DEBUGGING,
1158                                          * but not #ifdef-ed for bincompat */
1159 };
1160
1161 typedef struct stackinfo PERL_SI;
1162
1163 #define cxstack         (PL_curstackinfo->si_cxstack)
1164 #define cxstack_ix      (PL_curstackinfo->si_cxix)
1165 #define cxstack_max     (PL_curstackinfo->si_cxmax)
1166
1167 #ifdef DEBUGGING
1168 #  define       SET_MARK_OFFSET \
1169     PL_curstackinfo->si_markoff = PL_markstack_ptr - PL_markstack
1170 #else
1171 #  define       SET_MARK_OFFSET NOOP
1172 #endif
1173
1174 #define PUSHSTACKi(type) \
1175     STMT_START {                                                        \
1176         PERL_SI *next = PL_curstackinfo->si_next;                       \
1177         DEBUG_l({                                                       \
1178             int i = 0; PERL_SI *p = PL_curstackinfo;                    \
1179             while (p) { i++; p = p->si_prev; }                          \
1180             Perl_deb(aTHX_ "push STACKINFO %d at %s:%d\n",              \
1181                          i, __FILE__, __LINE__);})                      \
1182         if (!next) {                                                    \
1183             next = new_stackinfo(32, 2048/sizeof(PERL_CONTEXT) - 1);    \
1184             next->si_prev = PL_curstackinfo;                            \
1185             PL_curstackinfo->si_next = next;                            \
1186         }                                                               \
1187         next->si_type = type;                                           \
1188         next->si_cxix = -1;                                             \
1189         AvFILLp(next->si_stack) = 0;                                    \
1190         SWITCHSTACK(PL_curstack,next->si_stack);                        \
1191         PL_curstackinfo = next;                                         \
1192         SET_MARK_OFFSET;                                                \
1193     } STMT_END
1194
1195 #define PUSHSTACK PUSHSTACKi(PERLSI_UNKNOWN)
1196
1197 /* POPSTACK works with PL_stack_sp, so it may need to be bracketed by
1198  * PUTBACK/SPAGAIN to flush/refresh any local SP that may be active */
1199 #define POPSTACK \
1200     STMT_START {                                                        \
1201         dSP;                                                            \
1202         PERL_SI * const prev = PL_curstackinfo->si_prev;                \
1203         DEBUG_l({                                                       \
1204             int i = -1; PERL_SI *p = PL_curstackinfo;                   \
1205             while (p) { i++; p = p->si_prev; }                          \
1206             Perl_deb(aTHX_ "pop  STACKINFO %d at %s:%d\n",              \
1207                          i, __FILE__, __LINE__);})                      \
1208         if (!prev) {                                                    \
1209             Perl_croak_popstack();                                      \
1210         }                                                               \
1211         SWITCHSTACK(PL_curstack,prev->si_stack);                        \
1212         /* don't free prev here, free them all at the END{} */          \
1213         PL_curstackinfo = prev;                                         \
1214     } STMT_END
1215
1216 #define POPSTACK_TO(s) \
1217     STMT_START {                                                        \
1218         while (PL_curstack != s) {                                      \
1219             dounwind(-1);                                               \
1220             POPSTACK;                                                   \
1221         }                                                               \
1222     } STMT_END
1223
1224 #define IN_PERL_COMPILETIME     (PL_curcop == &PL_compiling)
1225 #define IN_PERL_RUNTIME         (PL_curcop != &PL_compiling)
1226
1227 /*
1228 =head1 Multicall Functions
1229
1230 =for apidoc Ams||dMULTICALL
1231 Declare local variables for a multicall.  See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1232
1233 =for apidoc Ams||PUSH_MULTICALL
1234 Opening bracket for a lightweight callback.
1235 See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1236
1237 =for apidoc Ams||MULTICALL
1238 Make a lightweight callback.  See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1239
1240 =for apidoc Ams||POP_MULTICALL
1241 Closing bracket for a lightweight callback.
1242 See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1243
1244 =cut
1245 */
1246
1247 #define dMULTICALL \
1248     SV **newsp;                 /* set by POPBLOCK */                   \
1249     PERL_CONTEXT *cx;                                                   \
1250     CV *multicall_cv;                                                   \
1251     OP *multicall_cop;                                                  \
1252     bool multicall_oldcatch;                                            \
1253     U8 hasargs = 0              /* used by PUSHSUB */
1254
1255 #define PUSH_MULTICALL(the_cv) \
1256     PUSH_MULTICALL_FLAGS(the_cv, 0)
1257
1258 /* Like PUSH_MULTICALL, but allows you to specify extra flags
1259  * for the CX stack entry (this isn't part of the public API) */
1260
1261 #define PUSH_MULTICALL_FLAGS(the_cv, flags) \
1262     STMT_START {                                                        \
1263         CV * const _nOnclAshIngNamE_ = the_cv;                          \
1264         CV * const cv = _nOnclAshIngNamE_;                              \
1265         PADLIST * const padlist = CvPADLIST(cv);                        \
1266         multicall_oldcatch = CATCH_GET;                                 \
1267         CATCH_SET(TRUE);                                                \
1268         PUSHSTACKi(PERLSI_MULTICALL);                                   \
1269         PUSHBLOCK(cx, (CXt_SUB|CXp_MULTICALL|flags), PL_stack_sp);      \
1270         PUSHSUB(cx);                                                    \
1271         cx->cx_u.cx_blk.blku_old_savestack_ix = PL_savestack_ix;        \
1272         SAVEVPTR(PL_op);                                                \
1273         if (!(flags & CXp_SUB_RE_FAKE))                                 \
1274             CvDEPTH(cv)++;                                              \
1275         if (CvDEPTH(cv) >= 2) {                                         \
1276             PERL_STACK_OVERFLOW_CHECK();                                \
1277             Perl_pad_push(aTHX_ padlist, CvDEPTH(cv));                  \
1278         }                                                               \
1279         PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));                       \
1280         multicall_cv = cv;                                              \
1281         multicall_cop = CvSTART(cv);                                    \
1282     } STMT_END
1283
1284 #define MULTICALL \
1285     STMT_START {                                                        \
1286         PL_op = multicall_cop;                                          \
1287         CALLRUNOPS(aTHX);                                               \
1288     } STMT_END
1289
1290 #define POP_MULTICALL \
1291     STMT_START {                                                        \
1292         cx = &cxstack[cxstack_ix];                                      \
1293         CvDEPTH(multicall_cv) = cx->blk_sub.olddepth;                   \
1294         /* includes partial unrolled POPSUB(): */                       \
1295         CX_LEAVE_SCOPE(cx);                                             \
1296         PL_comppad = cx->blk_sub.prevcomppad;                           \
1297         PL_curpad = LIKELY(PL_comppad) ? AvARRAY(PL_comppad) : NULL;    \
1298         SvREFCNT_dec_NN(multicall_cv);                                  \
1299         /* these two set for backcompat by callers */                   \
1300         newsp = PL_stack_base + cx->blk_oldsp;                          \
1301         gimme = cx->blk_gimme;                                          \
1302         POPBLOCK(cx);                                           \
1303         cxstack_ix--;                                                   \
1304         POPSTACK;                                                       \
1305         CATCH_SET(multicall_oldcatch);                                  \
1306         SPAGAIN;                                                        \
1307     } STMT_END
1308
1309 /* Change the CV of an already-pushed MULTICALL CxSUB block.
1310  * (this isn't part of the public API) */
1311
1312 #define CHANGE_MULTICALL_FLAGS(the_cv, flags) \
1313     STMT_START {                                                        \
1314         CV * const _nOnclAshIngNamE_ = the_cv;                          \
1315         CV * const cv = _nOnclAshIngNamE_;                              \
1316         PADLIST * const padlist = CvPADLIST(cv);                        \
1317         cx = &cxstack[cxstack_ix];                                      \
1318         assert(CxMULTICALL(cx));                                        \
1319         CvDEPTH(multicall_cv) = cx->blk_sub.olddepth;                   \
1320         SvREFCNT_dec_NN(multicall_cv);                                  \
1321         cx->cx_type = (CXt_SUB|CXp_MULTICALL|flags);                    \
1322         {                                                               \
1323             /* save a few things that we don't want PUSHSUB to zap */   \
1324             PAD * const prevcomppad = cx->blk_sub.prevcomppad;          \
1325             PUSHSUB(cx);                                                \
1326             /* undo the stuff that PUSHSUB zapped */                    \
1327             cx->blk_sub.prevcomppad = prevcomppad ;                     \
1328         }                                                               \
1329         if (!(flags & CXp_SUB_RE_FAKE))                                 \
1330             CvDEPTH(cv)++;                                              \
1331         if (CvDEPTH(cv) >= 2) {                                         \
1332             PERL_STACK_OVERFLOW_CHECK();                                \
1333             Perl_pad_push(aTHX_ padlist, CvDEPTH(cv));                  \
1334         }                                                               \
1335         PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));                       \
1336         multicall_cv = cv;                                              \
1337         multicall_cop = CvSTART(cv);                                    \
1338     } STMT_END
1339 /*
1340  * ex: set ts=8 sts=4 sw=4 et:
1341  */