Call get-magic once for CV-to-GV assignment
[perl.git] / cop.h
1 /*    cop.h
2  *
3  *    Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
4  *    2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 by Larry Wall and others
5  *
6  *    You may distribute under the terms of either the GNU General Public
7  *    License or the Artistic License, as specified in the README file.
8  *
9  * Control ops (cops) are one of the two ops OP_NEXTSTATE and OP_DBSTATE,
10  * that (loosely speaking) are separate statements.
11  * They hold information important for lexical state and error reporting.
12  * At run time, PL_curcop is set to point to the most recently executed cop,
13  * and thus can be used to determine our current state.
14  */
15
16 /* A jmpenv packages the state required to perform a proper non-local jump.
17  * Note that there is a PL_start_env initialized when perl starts, and
18  * PL_top_env points to this initially, so PL_top_env should always be
19  * non-null.
20  *
21  * Existence of a non-null PL_top_env->je_prev implies it is valid to call
22  * longjmp() at that runlevel (we make sure PL_start_env.je_prev is always
23  * null to ensure this).
24  *
25  * je_mustcatch, when set at any runlevel to TRUE, means eval ops must
26  * establish a local jmpenv to handle exception traps.  Care must be taken
27  * to restore the previous value of je_mustcatch before exiting the
28  * stack frame iff JMPENV_PUSH was not called in that stack frame.
29  * GSAR 97-03-27
30  */
31
32 struct jmpenv {
33     struct jmpenv *     je_prev;
34     Sigjmp_buf          je_buf;         /* only for use if !je_throw */
35     int                 je_ret;         /* last exception thrown */
36     bool                je_mustcatch;   /* need to call longjmp()? */
37 };
38
39 typedef struct jmpenv JMPENV;
40
41 #ifdef OP_IN_REGISTER
42 #define OP_REG_TO_MEM   PL_opsave = op
43 #define OP_MEM_TO_REG   op = PL_opsave
44 #else
45 #define OP_REG_TO_MEM   NOOP
46 #define OP_MEM_TO_REG   NOOP
47 #endif
48
49 /*
50  * How to build the first jmpenv.
51  *
52  * top_env needs to be non-zero. It points to an area
53  * in which longjmp() stuff is stored, as C callstack
54  * info there at least is thread specific this has to
55  * be per-thread. Otherwise a 'die' in a thread gives
56  * that thread the C stack of last thread to do an eval {}!
57  */
58
59 #define JMPENV_BOOTSTRAP \
60     STMT_START {                                \
61         Zero(&PL_start_env, 1, JMPENV);         \
62         PL_start_env.je_ret = -1;               \
63         PL_start_env.je_mustcatch = TRUE;       \
64         PL_top_env = &PL_start_env;             \
65     } STMT_END
66
67 /*
68  *   PERL_FLEXIBLE_EXCEPTIONS
69  * 
70  * All the flexible exceptions code has been removed.
71  * See the following threads for details:
72  *
73  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/2004-07/msg00378.html
74  * 
75  * Joshua's original patches (which weren't applied) and discussion:
76  * 
77  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01396.html
78  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01489.html
79  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01491.html
80  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01608.html
81  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg02144.html
82  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg02998.html
83  * 
84  * Chip's reworked patch and discussion:
85  * 
86  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1999-03/msg00520.html
87  * 
88  * The flaw in these patches (which went unnoticed at the time) was
89  * that they moved some code that could potentially die() out of the
90  * region protected by the setjmp()s.  This caused exceptions within
91  * END blocks and such to not be handled by the correct setjmp().
92  * 
93  * The original patches that introduces flexible exceptions were:
94  *
95  * http://perl5.git.perl.org/perl.git/commit/312caa8e97f1c7ee342a9895c2f0e749625b4929
96  * http://perl5.git.perl.org/perl.git/commit/14dd3ad8c9bf82cf09798a22cc89a9862dfd6d1a                                        
97  *  
98  */
99
100 #define dJMPENV         JMPENV cur_env
101
102 #define JMPENV_PUSH(v) \
103     STMT_START {                                                        \
104         DEBUG_l({                                                       \
105             int i = 0; JMPENV *p = PL_top_env;                          \
106             while (p) { i++; p = p->je_prev; }                          \
107             Perl_deb(aTHX_ "JUMPENV_PUSH level=%d at %s:%d\n",          \
108                          i,  __FILE__, __LINE__);})                     \
109         cur_env.je_prev = PL_top_env;                                   \
110         OP_REG_TO_MEM;                                                  \
111         cur_env.je_ret = PerlProc_setjmp(cur_env.je_buf, SCOPE_SAVES_SIGNAL_MASK);              \
112         OP_MEM_TO_REG;                                                  \
113         PL_top_env = &cur_env;                                          \
114         cur_env.je_mustcatch = FALSE;                                   \
115         (v) = cur_env.je_ret;                                           \
116     } STMT_END
117
118 #define JMPENV_POP \
119     STMT_START {                                                        \
120         DEBUG_l({                                                       \
121             int i = -1; JMPENV *p = PL_top_env;                         \
122             while (p) { i++; p = p->je_prev; }                          \
123             Perl_deb(aTHX_ "JUMPENV_POP level=%d at %s:%d\n",           \
124                          i, __FILE__, __LINE__);})                      \
125         assert(PL_top_env == &cur_env);                                 \
126         PL_top_env = cur_env.je_prev;                                   \
127     } STMT_END
128
129 #define JMPENV_JUMP(v) \
130     STMT_START {                                                \
131         DEBUG_l({                                               \
132             int i = -1; JMPENV *p = PL_top_env;                 \
133             while (p) { i++; p = p->je_prev; }                  \
134             Perl_deb(aTHX_ "JUMPENV_JUMP(%d) level=%d at %s:%d\n", \
135                          (int)v, i, __FILE__, __LINE__);})      \
136         OP_REG_TO_MEM;                                          \
137         if (PL_top_env->je_prev)                                \
138             PerlProc_longjmp(PL_top_env->je_buf, (v));          \
139         if ((v) == 2)                                           \
140             PerlProc_exit(STATUS_EXIT);                         \
141         PerlIO_printf(PerlIO_stderr(), "panic: top_env\n");     \
142         PerlProc_exit(1);                                       \
143     } STMT_END
144
145 #define CATCH_GET               (PL_top_env->je_mustcatch)
146 #define CATCH_SET(v) \
147     STMT_START {                                                        \
148         DEBUG_l(                                                        \
149             Perl_deb(aTHX_                                              \
150                 "JUMPLEVEL set catch %d => %d (for %p) at %s:%d\n",     \
151                  PL_top_env->je_mustcatch, v, (void*)PL_top_env,        \
152                  __FILE__, __LINE__);)                                  \
153         PL_top_env->je_mustcatch = (v);                                 \
154     } STMT_END
155
156 /*
157 =head1 COP Hint Hashes
158 */
159
160 typedef struct refcounted_he COPHH;
161
162 #define COPHH_KEY_UTF8 REFCOUNTED_HE_KEY_UTF8
163
164 /*
165 =for apidoc Amx|SV *|cophh_fetch_pvn|const COPHH *cophh|const char *keypv|STRLEN keylen|U32 hash|U32 flags
166
167 Look up the entry in the cop hints hash I<cophh> with the key specified by
168 I<keypv> and I<keylen>.  If I<flags> has the C<COPHH_KEY_UTF8> bit set,
169 the key octets are interpreted as UTF-8, otherwise they are interpreted
170 as Latin-1.  I<hash> is a precomputed hash of the key string, or zero if
171 it has not been precomputed.  Returns a mortal scalar copy of the value
172 associated with the key, or C<&PL_sv_placeholder> if there is no value
173 associated with the key.
174
175 =cut
176 */
177
178 #define cophh_fetch_pvn(cophh, keypv, keylen, hash, flags) \
179     Perl_refcounted_he_fetch_pvn(aTHX_ cophh, keypv, keylen, hash, flags)
180
181 /*
182 =for apidoc Amx|SV *|cophh_fetch_pvs|const COPHH *cophh|const char *key|U32 flags
183
184 Like L</cophh_fetch_pvn>, but takes a literal string instead of a
185 string/length pair, and no precomputed hash.
186
187 =cut
188 */
189
190 #define cophh_fetch_pvs(cophh, key, flags) \
191     Perl_refcounted_he_fetch_pvn(aTHX_ cophh, STR_WITH_LEN(key), 0, flags)
192
193 /*
194 =for apidoc Amx|SV *|cophh_fetch_pv|const COPHH *cophh|const char *key|U32 hash|U32 flags
195
196 Like L</cophh_fetch_pvn>, but takes a nul-terminated string instead of
197 a string/length pair.
198
199 =cut
200 */
201
202 #define cophh_fetch_pv(cophh, key, hash, flags) \
203     Perl_refcounted_he_fetch_pv(aTHX_ cophh, key, hash, flags)
204
205 /*
206 =for apidoc Amx|SV *|cophh_fetch_sv|const COPHH *cophh|SV *key|U32 hash|U32 flags
207
208 Like L</cophh_fetch_pvn>, but takes a Perl scalar instead of a
209 string/length pair.
210
211 =cut
212 */
213
214 #define cophh_fetch_sv(cophh, key, hash, flags) \
215     Perl_refcounted_he_fetch_sv(aTHX_ cophh, key, hash, flags)
216
217 /*
218 =for apidoc Amx|HV *|cophh_2hv|const COPHH *cophh|U32 flags
219
220 Generates and returns a standard Perl hash representing the full set of
221 key/value pairs in the cop hints hash I<cophh>.  I<flags> is currently
222 unused and must be zero.
223
224 =cut
225 */
226
227 #define cophh_2hv(cophh, flags) \
228     Perl_refcounted_he_chain_2hv(aTHX_ cophh, flags)
229
230 /*
231 =for apidoc Amx|COPHH *|cophh_copy|COPHH *cophh
232
233 Make and return a complete copy of the cop hints hash I<cophh>.
234
235 =cut
236 */
237
238 #define cophh_copy(cophh) Perl_refcounted_he_inc(aTHX_ cophh)
239
240 /*
241 =for apidoc Amx|void|cophh_free|COPHH *cophh
242
243 Discard the cop hints hash I<cophh>, freeing all resources associated
244 with it.
245
246 =cut
247 */
248
249 #define cophh_free(cophh) Perl_refcounted_he_free(aTHX_ cophh)
250
251 /*
252 =for apidoc Amx|COPHH *|cophh_new_empty
253
254 Generate and return a fresh cop hints hash containing no entries.
255
256 =cut
257 */
258
259 #define cophh_new_empty() ((COPHH *)NULL)
260
261 /*
262 =for apidoc Amx|COPHH *|cophh_store_pvn|COPHH *cophh|const char *keypv|STRLEN keylen|U32 hash|SV *value|U32 flags
263
264 Stores a value, associated with a key, in the cop hints hash I<cophh>,
265 and returns the modified hash.  The returned hash pointer is in general
266 not the same as the hash pointer that was passed in.  The input hash is
267 consumed by the function, and the pointer to it must not be subsequently
268 used.  Use L</cophh_copy> if you need both hashes.
269
270 The key is specified by I<keypv> and I<keylen>.  If I<flags> has the
271 C<COPHH_KEY_UTF8> bit set, the key octets are interpreted as UTF-8,
272 otherwise they are interpreted as Latin-1.  I<hash> is a precomputed
273 hash of the key string, or zero if it has not been precomputed.
274
275 I<value> is the scalar value to store for this key.  I<value> is copied
276 by this function, which thus does not take ownership of any reference
277 to it, and later changes to the scalar will not be reflected in the
278 value visible in the cop hints hash.  Complex types of scalar will not
279 be stored with referential integrity, but will be coerced to strings.
280
281 =cut
282 */
283
284 #define cophh_store_pvn(cophh, keypv, keylen, hash, value, flags) \
285     Perl_refcounted_he_new_pvn(aTHX_ cophh, keypv, keylen, hash, value, flags)
286
287 /*
288 =for apidoc Amx|COPHH *|cophh_store_pvs|const COPHH *cophh|const char *key|SV *value|U32 flags
289
290 Like L</cophh_store_pvn>, but takes a literal string instead of a
291 string/length pair, and no precomputed hash.
292
293 =cut
294 */
295
296 #define cophh_store_pvs(cophh, key, value, flags) \
297     Perl_refcounted_he_new_pvn(aTHX_ cophh, STR_WITH_LEN(key), 0, value, flags)
298
299 /*
300 =for apidoc Amx|COPHH *|cophh_store_pv|const COPHH *cophh|const char *key|U32 hash|SV *value|U32 flags
301
302 Like L</cophh_store_pvn>, but takes a nul-terminated string instead of
303 a string/length pair.
304
305 =cut
306 */
307
308 #define cophh_store_pv(cophh, key, hash, value, flags) \
309     Perl_refcounted_he_new_pv(aTHX_ cophh, key, hash, value, flags)
310
311 /*
312 =for apidoc Amx|COPHH *|cophh_store_sv|const COPHH *cophh|SV *key|U32 hash|SV *value|U32 flags
313
314 Like L</cophh_store_pvn>, but takes a Perl scalar instead of a
315 string/length pair.
316
317 =cut
318 */
319
320 #define cophh_store_sv(cophh, key, hash, value, flags) \
321     Perl_refcounted_he_new_sv(aTHX_ cophh, key, hash, value, flags)
322
323 /*
324 =for apidoc Amx|COPHH *|cophh_delete_pvn|COPHH *cophh|const char *keypv|STRLEN keylen|U32 hash|U32 flags
325
326 Delete a key and its associated value from the cop hints hash I<cophh>,
327 and returns the modified hash.  The returned hash pointer is in general
328 not the same as the hash pointer that was passed in.  The input hash is
329 consumed by the function, and the pointer to it must not be subsequently
330 used.  Use L</cophh_copy> if you need both hashes.
331
332 The key is specified by I<keypv> and I<keylen>.  If I<flags> has the
333 C<COPHH_KEY_UTF8> bit set, the key octets are interpreted as UTF-8,
334 otherwise they are interpreted as Latin-1.  I<hash> is a precomputed
335 hash of the key string, or zero if it has not been precomputed.
336
337 =cut
338 */
339
340 #define cophh_delete_pvn(cophh, keypv, keylen, hash, flags) \
341     Perl_refcounted_he_new_pvn(aTHX_ cophh, keypv, keylen, hash, \
342         (SV *)NULL, flags)
343
344 /*
345 =for apidoc Amx|COPHH *|cophh_delete_pvs|const COPHH *cophh|const char *key|U32 flags
346
347 Like L</cophh_delete_pvn>, but takes a literal string instead of a
348 string/length pair, and no precomputed hash.
349
350 =cut
351 */
352
353 #define cophh_delete_pvs(cophh, key, flags) \
354     Perl_refcounted_he_new_pvn(aTHX_ cophh, STR_WITH_LEN(key), 0, \
355         (SV *)NULL, flags)
356
357 /*
358 =for apidoc Amx|COPHH *|cophh_delete_pv|const COPHH *cophh|const char *key|U32 hash|U32 flags
359
360 Like L</cophh_delete_pvn>, but takes a nul-terminated string instead of
361 a string/length pair.
362
363 =cut
364 */
365
366 #define cophh_delete_pv(cophh, key, hash, flags) \
367     Perl_refcounted_he_new_pv(aTHX_ cophh, key, hash, (SV *)NULL, flags)
368
369 /*
370 =for apidoc Amx|COPHH *|cophh_delete_sv|const COPHH *cophh|SV *key|U32 hash|U32 flags
371
372 Like L</cophh_delete_pvn>, but takes a Perl scalar instead of a
373 string/length pair.
374
375 =cut
376 */
377
378 #define cophh_delete_sv(cophh, key, hash, flags) \
379     Perl_refcounted_he_new_sv(aTHX_ cophh, key, hash, (SV *)NULL, flags)
380
381 #include "mydtrace.h"
382
383 struct cop {
384     BASEOP
385     /* On LP64 putting this here takes advantage of the fact that BASEOP isn't
386        an exact multiple of 8 bytes to save structure padding.  */
387     line_t      cop_line;       /* line # of this command */
388     /* label for this construct is now stored in cop_hints_hash */
389 #ifdef USE_ITHREADS
390     char *      cop_stashpv;    /* package line was compiled in */
391     char *      cop_file;       /* file name the following line # is from */
392 #else
393     HV *        cop_stash;      /* package line was compiled in */
394     GV *        cop_filegv;     /* file the following line # is from */
395 #endif
396     U32         cop_hints;      /* hints bits from pragmata */
397     U32         cop_seq;        /* parse sequence number */
398     /* Beware. mg.c and warnings.pl assume the type of this is STRLEN *:  */
399     STRLEN *    cop_warnings;   /* lexical warnings bitmask */
400     /* compile time state of %^H.  See the comment in op.c for how this is
401        used to recreate a hash to return from caller.  */
402     COPHH *     cop_hints_hash;
403 };
404
405 #ifdef USE_ITHREADS
406 #  define CopFILE(c)            ((c)->cop_file)
407 #  define CopFILEGV(c)          (CopFILE(c) \
408                                  ? gv_fetchfile(CopFILE(c)) : NULL)
409                                  
410 #  ifdef NETWARE
411 #    define CopFILE_set(c,pv)   ((c)->cop_file = savepv(pv))
412 #    define CopFILE_setn(c,pv,l)  ((c)->cop_file = savepv((pv),(l)))
413 #  else
414 #    define CopFILE_set(c,pv)   ((c)->cop_file = savesharedpv(pv))
415 #    define CopFILE_setn(c,pv,l)  ((c)->cop_file = savesharedpvn((pv),(l)))
416 #  endif
417
418 #  define CopFILESV(c)          (CopFILE(c) \
419                                  ? GvSV(gv_fetchfile(CopFILE(c))) : NULL)
420 #  define CopFILEAV(c)          (CopFILE(c) \
421                                  ? GvAV(gv_fetchfile(CopFILE(c))) : NULL)
422 #  ifdef DEBUGGING
423 #    define CopFILEAVx(c)       (assert(CopFILE(c)), \
424                                    GvAV(gv_fetchfile(CopFILE(c))))
425 #  else
426 #    define CopFILEAVx(c)       (GvAV(gv_fetchfile(CopFILE(c))))
427 #  endif
428 #  define CopSTASHPV(c)         ((c)->cop_stashpv)
429
430 #  ifdef NETWARE
431 #    define CopSTASHPV_set(c,pv)        ((c)->cop_stashpv = ((pv) ? savepv(pv) : NULL))
432 #  else
433 #    define CopSTASHPV_set(c,pv)        ((c)->cop_stashpv = savesharedpv(pv))
434 #  endif
435
436 #  define CopSTASH(c)           (CopSTASHPV(c) \
437                                  ? gv_stashpv(CopSTASHPV(c),GV_ADD) : NULL)
438 #  define CopSTASH_set(c,hv)    CopSTASHPV_set(c, (hv) ? HvNAME_get(hv) : NULL)
439 #  define CopSTASH_eq(c,hv)     ((hv) && stashpv_hvname_match(c,hv))
440 #  ifdef NETWARE
441 #    define CopSTASH_free(c) SAVECOPSTASH_FREE(c)
442 #    define CopFILE_free(c) SAVECOPFILE_FREE(c)
443 #  else
444 #    define CopSTASH_free(c)    PerlMemShared_free(CopSTASHPV(c))
445 #    define CopFILE_free(c)     (PerlMemShared_free(CopFILE(c)),(CopFILE(c) = NULL))
446 #  endif
447 #else
448 #  define CopFILEGV(c)          ((c)->cop_filegv)
449 #  define CopFILEGV_set(c,gv)   ((c)->cop_filegv = (GV*)SvREFCNT_inc(gv))
450 #  define CopFILE_set(c,pv)     CopFILEGV_set((c), gv_fetchfile(pv))
451 #  define CopFILE_setn(c,pv,l)  CopFILEGV_set((c), gv_fetchfile_flags((pv),(l),0))
452 #  define CopFILESV(c)          (CopFILEGV(c) ? GvSV(CopFILEGV(c)) : NULL)
453 #  define CopFILEAV(c)          (CopFILEGV(c) ? GvAV(CopFILEGV(c)) : NULL)
454 #  ifdef DEBUGGING
455 #    define CopFILEAVx(c)       (assert(CopFILEGV(c)), GvAV(CopFILEGV(c)))
456 #  else
457 #    define CopFILEAVx(c)       (GvAV(CopFILEGV(c)))
458 # endif
459 #  define CopFILE(c)            (CopFILEGV(c) && GvSV(CopFILEGV(c)) \
460                                     ? SvPVX(GvSV(CopFILEGV(c))) : NULL)
461 #  define CopSTASH(c)           ((c)->cop_stash)
462 #  define CopSTASH_set(c,hv)    ((c)->cop_stash = (hv))
463 #  define CopSTASHPV(c)         (CopSTASH(c) ? HvNAME_get(CopSTASH(c)) : NULL)
464    /* cop_stash is not refcounted */
465 #  define CopSTASHPV_set(c,pv)  CopSTASH_set((c), gv_stashpv(pv,GV_ADD))
466 #  define CopSTASH_eq(c,hv)     (CopSTASH(c) == (hv))
467 #  define CopSTASH_free(c)      
468 #  define CopFILE_free(c)       (SvREFCNT_dec(CopFILEGV(c)),(CopFILEGV(c) = NULL))
469
470 #endif /* USE_ITHREADS */
471
472 #define CopHINTHASH_get(c)      ((COPHH*)((c)->cop_hints_hash))
473 #define CopHINTHASH_set(c,h)    ((c)->cop_hints_hash = (h))
474
475 /*
476 =head1 COP Hint Reading
477 */
478
479 /*
480 =for apidoc Am|SV *|cop_hints_fetch_pvn|const COP *cop|const char *keypv|STRLEN keylen|U32 hash|U32 flags
481
482 Look up the hint entry in the cop I<cop> with the key specified by
483 I<keypv> and I<keylen>.  If I<flags> has the C<COPHH_KEY_UTF8> bit set,
484 the key octets are interpreted as UTF-8, otherwise they are interpreted
485 as Latin-1.  I<hash> is a precomputed hash of the key string, or zero if
486 it has not been precomputed.  Returns a mortal scalar copy of the value
487 associated with the key, or C<&PL_sv_placeholder> if there is no value
488 associated with the key.
489
490 =cut
491 */
492
493 #define cop_hints_fetch_pvn(cop, keypv, keylen, hash, flags) \
494     cophh_fetch_pvn(CopHINTHASH_get(cop), keypv, keylen, hash, flags)
495
496 /*
497 =for apidoc Am|SV *|cop_hints_fetch_pvs|const COP *cop|const char *key|U32 flags
498
499 Like L</cop_hints_fetch_pvn>, but takes a literal string instead of a
500 string/length pair, and no precomputed hash.
501
502 =cut
503 */
504
505 #define cop_hints_fetch_pvs(cop, key, flags) \
506     cophh_fetch_pvs(CopHINTHASH_get(cop), key, flags)
507
508 /*
509 =for apidoc Am|SV *|cop_hints_fetch_pv|const COP *cop|const char *key|U32 hash|U32 flags
510
511 Like L</cop_hints_fetch_pvn>, but takes a nul-terminated string instead
512 of a string/length pair.
513
514 =cut
515 */
516
517 #define cop_hints_fetch_pv(cop, key, hash, flags) \
518     cophh_fetch_pv(CopHINTHASH_get(cop), key, hash, flags)
519
520 /*
521 =for apidoc Am|SV *|cop_hints_fetch_sv|const COP *cop|SV *key|U32 hash|U32 flags
522
523 Like L</cop_hints_fetch_pvn>, but takes a Perl scalar instead of a
524 string/length pair.
525
526 =cut
527 */
528
529 #define cop_hints_fetch_sv(cop, key, hash, flags) \
530     cophh_fetch_sv(CopHINTHASH_get(cop), key, hash, flags)
531
532 /*
533 =for apidoc Am|HV *|cop_hints_2hv|const COP *cop|U32 flags
534
535 Generates and returns a standard Perl hash representing the full set of
536 hint entries in the cop I<cop>.  I<flags> is currently unused and must
537 be zero.
538
539 =cut
540 */
541
542 #define cop_hints_2hv(cop, flags) \
543     cophh_2hv(CopHINTHASH_get(cop), flags)
544
545 #define CopLABEL(c)  Perl_cop_fetch_label(aTHX_ (c), NULL, NULL)
546 #define CopLABEL_alloc(pv)      ((pv)?savepv(pv):NULL)
547
548 #define CopSTASH_ne(c,hv)       (!CopSTASH_eq(c,hv))
549 #define CopLINE(c)              ((c)->cop_line)
550 #define CopLINE_inc(c)          (++CopLINE(c))
551 #define CopLINE_dec(c)          (--CopLINE(c))
552 #define CopLINE_set(c,l)        (CopLINE(c) = (l))
553
554 /* OutCopFILE() is CopFILE for output (caller, die, warn, etc.) */
555 #define OutCopFILE(c) CopFILE(c)
556
557 /* If $[ is non-zero, it's stored in cop_hints under the key "$[", and
558    HINT_ARYBASE is set to indicate this.
559    Setting it is inefficient due to the need to create 2 mortal SVs, but as
560    using $[ is highly discouraged, no sane Perl code will be using it.  */
561 #define CopARYBASE_get(c)       \
562         ((CopHINTS_get(c) & HINT_ARYBASE)                               \
563          ? SvIV(cop_hints_fetch_pvs((c), "$[", 0))                      \
564          : 0)
565 #define CopARYBASE_set(c, b) STMT_START { \
566         if (b || ((c)->cop_hints & HINT_ARYBASE)) {                     \
567             (c)->cop_hints |= HINT_ARYBASE;                             \
568             if ((c) == &PL_compiling) {                                 \
569                 SV *val = newSViv(b);                                   \
570                 (void)hv_stores(GvHV(PL_hintgv), "$[", val);            \
571                 mg_set(val);                                            \
572                 PL_hints |= HINT_ARYBASE;                               \
573             } else {                                                    \
574                 CopHINTHASH_set((c),                                    \
575                     cophh_store_pvs(CopHINTHASH_get((c)), "$[",         \
576                         sv_2mortal(newSViv(b)), 0));                    \
577             }                                                           \
578         }                                                               \
579     } STMT_END
580
581 /* FIXME NATIVE_HINTS if this is changed from op_private (see perl.h)  */
582 #define CopHINTS_get(c)         ((c)->cop_hints + 0)
583 #define CopHINTS_set(c, h)      STMT_START {                            \
584                                     (c)->cop_hints = (h);               \
585                                 } STMT_END
586
587 /*
588  * Here we have some enormously heavy (or at least ponderous) wizardry.
589  */
590
591 /* subroutine context */
592 struct block_sub {
593     OP *        retop;  /* op to execute on exit from sub */
594     /* Above here is the same for sub, format and eval.  */
595     CV *        cv;
596     /* Above here is the same for sub and format.  */
597     AV *        savearray;
598     AV *        argarray;
599     I32         olddepth;
600     PAD         *oldcomppad;
601 };
602
603
604 /* format context */
605 struct block_format {
606     OP *        retop;  /* op to execute on exit from sub */
607     /* Above here is the same for sub, format and eval.  */
608     CV *        cv;
609     /* Above here is the same for sub and format.  */
610     GV *        gv;
611     GV *        dfoutgv;
612 };
613
614 /* base for the next two macros. Don't use directly.
615  * Note that the refcnt of the cv is incremented twice;  The CX one is
616  * decremented by LEAVESUB, the other by LEAVE. */
617
618 #define PUSHSUB_BASE(cx)                                                \
619         ENTRY_PROBE(GvENAME(CvGV(cv)),                                  \
620                 CopFILE((const COP *)CvSTART(cv)),                      \
621                 CopLINE((const COP *)CvSTART(cv)),                      \
622                 CopSTASHPV((const COP *)CvSTART(cv)));                  \
623                                                                         \
624         cx->blk_sub.cv = cv;                                            \
625         cx->blk_sub.olddepth = CvDEPTH(cv);                             \
626         cx->cx_type |= (hasargs) ? CXp_HASARGS : 0;                     \
627         cx->blk_sub.retop = NULL;                                       \
628         if (!CvDEPTH(cv)) {                                             \
629             SvREFCNT_inc_simple_void_NN(cv);                            \
630             SvREFCNT_inc_simple_void_NN(cv);                            \
631             SAVEFREESV(cv);                                             \
632         }
633
634
635 #define PUSHSUB(cx)                                                     \
636     {                                                                   \
637         /* If the context is indeterminate, then only the lvalue */     \
638         /* flags that the caller also has are applicable.        */     \
639         U8 phlags =                                                     \
640            (PL_op->op_flags & OPf_WANT)                                 \
641                ? OPpENTERSUB_LVAL_MASK                                  \
642                : !(PL_op->op_private & OPpENTERSUB_LVAL_MASK)           \
643                    ? 0 : Perl_was_lvalue_sub(aTHX);                     \
644         PUSHSUB_BASE(cx)                                                \
645         cx->blk_u16 = PL_op->op_private &                               \
646                           (phlags|OPpDEREF);                            \
647     }
648
649 /* variant for use by OP_DBSTATE, where op_private holds hint bits */
650 #define PUSHSUB_DB(cx)                                                  \
651         PUSHSUB_BASE(cx)                                                \
652         cx->blk_u16 = 0;
653
654
655 #define PUSHFORMAT(cx, retop)                                           \
656         cx->blk_format.cv = cv;                                         \
657         cx->blk_format.gv = gv;                                         \
658         cx->blk_format.retop = (retop);                                 \
659         cx->blk_format.dfoutgv = PL_defoutgv;                           \
660         SvREFCNT_inc_void(cx->blk_format.dfoutgv)
661
662 #define POP_SAVEARRAY()                                         \
663     STMT_START {                                                        \
664         SvREFCNT_dec(GvAV(PL_defgv));                                   \
665         GvAV(PL_defgv) = cx->blk_sub.savearray;                         \
666     } STMT_END
667
668 /* junk in @_ spells trouble when cloning CVs and in pp_caller(), so don't
669  * leave any (a fast av_clear(ary), basically) */
670 #define CLEAR_ARGARRAY(ary) \
671     STMT_START {                                                        \
672         AvMAX(ary) += AvARRAY(ary) - AvALLOC(ary);                      \
673         AvARRAY(ary) = AvALLOC(ary);                                    \
674         AvFILLp(ary) = -1;                                              \
675     } STMT_END
676
677 #define POPSUB(cx,sv)                                                   \
678     STMT_START {                                                        \
679         RETURN_PROBE(GvENAME(CvGV((const CV*)cx->blk_sub.cv)),          \
680                 CopFILE((COP*)CvSTART((const CV*)cx->blk_sub.cv)),      \
681                 CopLINE((COP*)CvSTART((const CV*)cx->blk_sub.cv)),      \
682                 CopSTASHPV((COP*)CvSTART((const CV*)cx->blk_sub.cv)));  \
683                                                                         \
684         if (CxHASARGS(cx)) {                                            \
685             POP_SAVEARRAY();                                            \
686             /* abandon @_ if it got reified */                          \
687             if (AvREAL(cx->blk_sub.argarray)) {                         \
688                 const SSize_t fill = AvFILLp(cx->blk_sub.argarray);     \
689                 SvREFCNT_dec(cx->blk_sub.argarray);                     \
690                 cx->blk_sub.argarray = newAV();                         \
691                 av_extend(cx->blk_sub.argarray, fill);                  \
692                 AvREIFY_only(cx->blk_sub.argarray);                     \
693                 CX_CURPAD_SV(cx->blk_sub, 0) = MUTABLE_SV(cx->blk_sub.argarray); \
694             }                                                           \
695             else {                                                      \
696                 CLEAR_ARGARRAY(cx->blk_sub.argarray);                   \
697             }                                                           \
698         }                                                               \
699         sv = MUTABLE_SV(cx->blk_sub.cv);                                \
700         if (sv && (CvDEPTH((const CV*)sv) = cx->blk_sub.olddepth))      \
701             sv = NULL;                                          \
702     } STMT_END
703
704 #define LEAVESUB(sv)                                                    \
705     STMT_START {                                                        \
706         if (sv)                                                         \
707             SvREFCNT_dec(sv);                                           \
708     } STMT_END
709
710 #define POPFORMAT(cx)                                                   \
711         setdefout(cx->blk_format.dfoutgv);                              \
712         SvREFCNT_dec(cx->blk_format.dfoutgv);
713
714 /* eval context */
715 struct block_eval {
716     OP *        retop;  /* op to execute on exit from eval */
717     /* Above here is the same for sub, format and eval.  */
718     SV *        old_namesv;
719     OP *        old_eval_root;
720     SV *        cur_text;
721     CV *        cv;
722     JMPENV *    cur_top_env; /* value of PL_top_env when eval CX created */
723 };
724
725 /* If we ever need more than 512 op types, change the shift from 7.
726    blku_gimme is actually also only 2 bits, so could be merged with something.
727 */
728
729 #define CxOLD_IN_EVAL(cx)       (((cx)->blk_u16) & 0x7F)
730 #define CxOLD_OP_TYPE(cx)       (((cx)->blk_u16) >> 7)
731
732 #define PUSHEVAL(cx,n)                                                  \
733     STMT_START {                                                        \
734         assert(!(PL_in_eval & ~0x7F));                                  \
735         assert(!(PL_op->op_type & ~0x1FF));                             \
736         cx->blk_u16 = (PL_in_eval & 0x7F) | ((U16)PL_op->op_type << 7); \
737         cx->blk_eval.old_namesv = (n ? newSVpv(n,0) : NULL);            \
738         cx->blk_eval.old_eval_root = PL_eval_root;                      \
739         cx->blk_eval.cur_text = PL_parser ? PL_parser->linestr : NULL;  \
740         cx->blk_eval.cv = NULL; /* set by doeval(), as applicable */    \
741         cx->blk_eval.retop = NULL;                                      \
742         cx->blk_eval.cur_top_env = PL_top_env;                          \
743     } STMT_END
744
745 #define POPEVAL(cx)                                                     \
746     STMT_START {                                                        \
747         PL_in_eval = CxOLD_IN_EVAL(cx);                                 \
748         optype = CxOLD_OP_TYPE(cx);                                     \
749         PL_eval_root = cx->blk_eval.old_eval_root;                      \
750         if (cx->blk_eval.old_namesv)                                    \
751             sv_2mortal(cx->blk_eval.old_namesv);                        \
752     } STMT_END
753
754 /* loop context */
755 struct block_loop {
756     I32         resetsp;
757     LOOP *      my_op;  /* My op, that contains redo, next and last ops.  */
758     union {     /* different ways of locating the iteration variable */
759         SV      **svp;
760         GV      *gv;
761         PAD     *oldcomppad; /* only used in ITHREADS */
762     } itervar_u;
763     union {
764         struct { /* valid if type is LOOP_FOR or LOOP_PLAIN (but {NULL,0})*/
765             AV * ary; /* use the stack if this is NULL */
766             IV ix;
767         } ary;
768         struct { /* valid if type is LOOP_LAZYIV */
769             IV cur;
770             IV end;
771         } lazyiv;
772         struct { /* valid if type if LOOP_LAZYSV */
773             SV * cur;
774             SV * end; /* maxiumum value (or minimum in reverse) */
775         } lazysv;
776     } state_u;
777 };
778
779 #ifdef USE_ITHREADS
780 #  define CxITERVAR_PADSV(c) \
781         &CX_CURPAD_SV( (c)->blk_loop.itervar_u, (c)->blk_loop.my_op->op_targ)
782 #else
783 #  define CxITERVAR_PADSV(c) ((c)->blk_loop.itervar_u.svp)
784 #endif
785
786 #define CxITERVAR(c)                                                    \
787         ((c)->blk_loop.itervar_u.oldcomppad                             \
788          ? (CxPADLOOP(c)                                                \
789             ? CxITERVAR_PADSV(c)                                        \
790             : &GvSV((c)->blk_loop.itervar_u.gv))                        \
791          : (SV**)NULL)
792
793 #define CxLABEL(c)      (0 + CopLABEL((c)->blk_oldcop))
794 #define CxHASARGS(c)    (((c)->cx_type & CXp_HASARGS) == CXp_HASARGS)
795 #define CxLVAL(c)       (0 + (c)->blk_u16)
796
797 #define PUSHLOOP_PLAIN(cx, s)                                           \
798         cx->blk_loop.resetsp = s - PL_stack_base;                       \
799         cx->blk_loop.my_op = cLOOP;                                     \
800         cx->blk_loop.state_u.ary.ary = NULL;                            \
801         cx->blk_loop.state_u.ary.ix = 0;                                \
802         cx->blk_loop.itervar_u.svp = NULL;
803
804 #define PUSHLOOP_FOR(cx, ivar, s)                                       \
805         cx->blk_loop.resetsp = s - PL_stack_base;                       \
806         cx->blk_loop.my_op = cLOOP;                                     \
807         cx->blk_loop.state_u.ary.ary = NULL;                            \
808         cx->blk_loop.state_u.ary.ix = 0;                                \
809         cx->blk_loop.itervar_u.svp = (SV**)(ivar);
810
811 #define POPLOOP(cx)                                                     \
812         if (CxTYPE(cx) == CXt_LOOP_LAZYSV) {                            \
813             SvREFCNT_dec(cx->blk_loop.state_u.lazysv.cur);              \
814             SvREFCNT_dec(cx->blk_loop.state_u.lazysv.end);              \
815         }                                                               \
816         if (CxTYPE(cx) == CXt_LOOP_FOR)                                 \
817             SvREFCNT_dec(cx->blk_loop.state_u.ary.ary);
818
819 /* given/when context */
820 struct block_givwhen {
821         OP *leave_op;
822 };
823
824 #define PUSHGIVEN(cx)                                                   \
825         cx->blk_givwhen.leave_op = cLOGOP->op_other;
826
827 #define PUSHWHEN PUSHGIVEN
828
829 /* context common to subroutines, evals and loops */
830 struct block {
831     U8          blku_type;      /* what kind of context this is */
832     U8          blku_gimme;     /* is this block running in list context? */
833     U16         blku_u16;       /* used by block_sub and block_eval (so far) */
834     I32         blku_oldsp;     /* stack pointer to copy stuff down to */
835     COP *       blku_oldcop;    /* old curcop pointer */
836     I32         blku_oldmarksp; /* mark stack index */
837     I32         blku_oldscopesp;        /* scope stack index */
838     PMOP *      blku_oldpm;     /* values of pattern match vars */
839
840     union {
841         struct block_sub        blku_sub;
842         struct block_format     blku_format;
843         struct block_eval       blku_eval;
844         struct block_loop       blku_loop;
845         struct block_givwhen    blku_givwhen;
846     } blk_u;
847 };
848 #define blk_oldsp       cx_u.cx_blk.blku_oldsp
849 #define blk_oldcop      cx_u.cx_blk.blku_oldcop
850 #define blk_oldmarksp   cx_u.cx_blk.blku_oldmarksp
851 #define blk_oldscopesp  cx_u.cx_blk.blku_oldscopesp
852 #define blk_oldpm       cx_u.cx_blk.blku_oldpm
853 #define blk_gimme       cx_u.cx_blk.blku_gimme
854 #define blk_u16         cx_u.cx_blk.blku_u16
855 #define blk_sub         cx_u.cx_blk.blk_u.blku_sub
856 #define blk_format      cx_u.cx_blk.blk_u.blku_format
857 #define blk_eval        cx_u.cx_blk.blk_u.blku_eval
858 #define blk_loop        cx_u.cx_blk.blk_u.blku_loop
859 #define blk_givwhen     cx_u.cx_blk.blk_u.blku_givwhen
860
861 #define DEBUG_CX(action)                                                \
862     DEBUG_l(                                                            \
863         Perl_deb(aTHX_ "CX %ld %s %s (scope %ld,%ld) at %s:%d\n",       \
864                     (long)cxstack_ix,                                   \
865                     action,                                             \
866                     PL_block_type[CxTYPE(&cxstack[cxstack_ix])],        \
867                     (long)PL_scopestack_ix,                             \
868                     (long)(cxstack[cxstack_ix].blk_oldscopesp),         \
869                     __FILE__, __LINE__));
870
871 /* Enter a block. */
872 #define PUSHBLOCK(cx,t,sp) CXINC, cx = &cxstack[cxstack_ix],            \
873         cx->cx_type             = t,                                    \
874         cx->blk_oldsp           = sp - PL_stack_base,                   \
875         cx->blk_oldcop          = PL_curcop,                            \
876         cx->blk_oldmarksp       = PL_markstack_ptr - PL_markstack,      \
877         cx->blk_oldscopesp      = PL_scopestack_ix,                     \
878         cx->blk_oldpm           = PL_curpm,                             \
879         cx->blk_gimme           = (U8)gimme;                            \
880         DEBUG_CX("PUSH");
881
882 /* Exit a block (RETURN and LAST). */
883 #define POPBLOCK(cx,pm)                                                 \
884         DEBUG_CX("POP");                                                \
885         cx = &cxstack[cxstack_ix--],                                    \
886         newsp            = PL_stack_base + cx->blk_oldsp,               \
887         PL_curcop        = cx->blk_oldcop,                              \
888         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
889         PL_scopestack_ix = cx->blk_oldscopesp,                          \
890         pm               = cx->blk_oldpm,                               \
891         gimme            = cx->blk_gimme;
892
893 /* Continue a block elsewhere (NEXT and REDO). */
894 #define TOPBLOCK(cx)                                                    \
895         DEBUG_CX("TOP");                                                \
896         cx  = &cxstack[cxstack_ix],                                     \
897         PL_stack_sp      = PL_stack_base + cx->blk_oldsp,               \
898         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
899         PL_scopestack_ix = cx->blk_oldscopesp,                          \
900         PL_curpm         = cx->blk_oldpm;
901
902 /* substitution context */
903 struct subst {
904     U8          sbu_type;       /* what kind of context this is */
905     U8          sbu_rflags;
906     U16         sbu_rxtainted;  /* matches struct block */
907     I32         sbu_iters;
908     I32         sbu_maxiters;
909     I32         sbu_oldsave;
910     char *      sbu_orig;
911     SV *        sbu_dstr;
912     SV *        sbu_targ;
913     char *      sbu_s;
914     char *      sbu_m;
915     char *      sbu_strend;
916     void *      sbu_rxres;
917     REGEXP *    sbu_rx;
918 };
919 #define sb_iters        cx_u.cx_subst.sbu_iters
920 #define sb_maxiters     cx_u.cx_subst.sbu_maxiters
921 #define sb_rflags       cx_u.cx_subst.sbu_rflags
922 #define sb_oldsave      cx_u.cx_subst.sbu_oldsave
923 #define sb_rxtainted    cx_u.cx_subst.sbu_rxtainted
924 #define sb_orig         cx_u.cx_subst.sbu_orig
925 #define sb_dstr         cx_u.cx_subst.sbu_dstr
926 #define sb_targ         cx_u.cx_subst.sbu_targ
927 #define sb_s            cx_u.cx_subst.sbu_s
928 #define sb_m            cx_u.cx_subst.sbu_m
929 #define sb_strend       cx_u.cx_subst.sbu_strend
930 #define sb_rxres        cx_u.cx_subst.sbu_rxres
931 #define sb_rx           cx_u.cx_subst.sbu_rx
932
933 #ifdef PERL_CORE
934 #  define PUSHSUBST(cx) CXINC, cx = &cxstack[cxstack_ix],               \
935         cx->sb_iters            = iters,                                \
936         cx->sb_maxiters         = maxiters,                             \
937         cx->sb_rflags           = r_flags,                              \
938         cx->sb_oldsave          = oldsave,                              \
939         cx->sb_rxtainted        = rxtainted,                            \
940         cx->sb_orig             = orig,                                 \
941         cx->sb_dstr             = dstr,                                 \
942         cx->sb_targ             = targ,                                 \
943         cx->sb_s                = s,                                    \
944         cx->sb_m                = m,                                    \
945         cx->sb_strend           = strend,                               \
946         cx->sb_rxres            = NULL,                                 \
947         cx->sb_rx               = rx,                                   \
948         cx->cx_type             = CXt_SUBST | (once ? CXp_ONCE : 0);    \
949         rxres_save(&cx->sb_rxres, rx);                                  \
950         (void)ReREFCNT_inc(rx)
951
952 #  define POPSUBST(cx) cx = &cxstack[cxstack_ix--];                     \
953         rxres_free(&cx->sb_rxres);                                      \
954         ReREFCNT_dec(cx->sb_rx)
955 #endif
956
957 #define CxONCE(cx)              ((cx)->cx_type & CXp_ONCE)
958
959 struct context {
960     union {
961         struct block    cx_blk;
962         struct subst    cx_subst;
963     } cx_u;
964 };
965 #define cx_type cx_u.cx_subst.sbu_type
966
967 /* If you re-order these, there is also an array of uppercase names in perl.h
968    and a static array of context names in pp_ctl.c  */
969 #define CXTYPEMASK      0xf
970 #define CXt_NULL        0
971 #define CXt_WHEN        1
972 #define CXt_BLOCK       2
973 /* When micro-optimising :-) keep GIVEN next to the LOOPs, as these 5 share a
974    jump table in pp_ctl.c
975    The first 4 don't have a 'case' in at least one switch statement in pp_ctl.c
976 */
977 #define CXt_GIVEN       3
978 /* This is first so that CXt_LOOP_FOR|CXt_LOOP_LAZYIV is CXt_LOOP_LAZYIV */
979 #define CXt_LOOP_FOR    4
980 #define CXt_LOOP_PLAIN  5
981 #define CXt_LOOP_LAZYSV 6
982 #define CXt_LOOP_LAZYIV 7
983 #define CXt_SUB         8
984 #define CXt_FORMAT      9
985 #define CXt_EVAL       10
986 #define CXt_SUBST      11
987 /* SUBST doesn't feature in all switch statements.  */
988
989 /* private flags for CXt_SUB and CXt_NULL
990    However, this is checked in many places which do not check the type, so
991    this bit needs to be kept clear for most everything else. For reasons I
992    haven't investigated, it can coexist with CXp_FOR_DEF */
993 #define CXp_MULTICALL   0x10    /* part of a multicall (so don't
994                                    tear down context on exit). */ 
995
996 /* private flags for CXt_SUB and CXt_FORMAT */
997 #define CXp_HASARGS     0x20
998
999 /* private flags for CXt_EVAL */
1000 #define CXp_REAL        0x20    /* truly eval'', not a lookalike */
1001 #define CXp_TRYBLOCK    0x40    /* eval{}, not eval'' or similar */
1002
1003 /* private flags for CXt_LOOP */
1004 #define CXp_FOR_DEF     0x10    /* foreach using $_ */
1005 #define CxPADLOOP(c)    ((c)->blk_loop.my_op->op_targ)
1006
1007 /* private flags for CXt_SUBST */
1008 #define CXp_ONCE        0x10    /* What was sbu_once in struct subst */
1009
1010 #define CxTYPE(c)       ((c)->cx_type & CXTYPEMASK)
1011 #define CxTYPE_is_LOOP(c)       (((c)->cx_type & 0xC) == 0x4)
1012 #define CxMULTICALL(c)  (((c)->cx_type & CXp_MULTICALL)                 \
1013                          == CXp_MULTICALL)
1014 #define CxREALEVAL(c)   (((c)->cx_type & (CXTYPEMASK|CXp_REAL))         \
1015                          == (CXt_EVAL|CXp_REAL))
1016 #define CxTRYBLOCK(c)   (((c)->cx_type & (CXTYPEMASK|CXp_TRYBLOCK))     \
1017                          == (CXt_EVAL|CXp_TRYBLOCK))
1018 #define CxFOREACH(c)    (CxTYPE_is_LOOP(c) && CxTYPE(c) != CXt_LOOP_PLAIN)
1019 #define CxFOREACHDEF(c) ((CxTYPE_is_LOOP(c) && CxTYPE(c) != CXt_LOOP_PLAIN) \
1020                          && ((c)->cx_type & CXp_FOR_DEF))
1021
1022 #define CXINC (cxstack_ix < cxstack_max ? ++cxstack_ix : (cxstack_ix = cxinc()))
1023
1024 /* 
1025 =head1 "Gimme" Values
1026 */
1027
1028 /*
1029 =for apidoc AmU||G_SCALAR
1030 Used to indicate scalar context.  See C<GIMME_V>, C<GIMME>, and
1031 L<perlcall>.
1032
1033 =for apidoc AmU||G_ARRAY
1034 Used to indicate list context.  See C<GIMME_V>, C<GIMME> and
1035 L<perlcall>.
1036
1037 =for apidoc AmU||G_VOID
1038 Used to indicate void context.  See C<GIMME_V> and L<perlcall>.
1039
1040 =for apidoc AmU||G_DISCARD
1041 Indicates that arguments returned from a callback should be discarded.  See
1042 L<perlcall>.
1043
1044 =for apidoc AmU||G_EVAL
1045
1046 Used to force a Perl C<eval> wrapper around a callback.  See
1047 L<perlcall>.
1048
1049 =for apidoc AmU||G_NOARGS
1050
1051 Indicates that no arguments are being sent to a callback.  See
1052 L<perlcall>.
1053
1054 =cut
1055 */
1056
1057 #define G_SCALAR        2
1058 #define G_ARRAY         3
1059 #define G_VOID          1
1060 #define G_WANT          3
1061
1062 /* extra flags for Perl_call_* routines */
1063 #define G_DISCARD       4       /* Call FREETMPS.
1064                                    Don't change this without consulting the
1065                                    hash actions codes defined in hv.h */
1066 #define G_EVAL          8       /* Assume eval {} around subroutine call. */
1067 #define G_NOARGS       16       /* Don't construct a @_ array. */
1068 #define G_KEEPERR      32       /* Warn for errors, don't overwrite $@ */
1069 #define G_NODEBUG      64       /* Disable debugging at toplevel.  */
1070 #define G_METHOD      128       /* Calling method. */
1071 #define G_FAKINGEVAL  256       /* Faking an eval context for call_sv or
1072                                    fold_constants. */
1073 #define G_UNDEF_FILL  512       /* Fill the stack with &PL_sv_undef
1074                                    A special case for UNSHIFT in
1075                                    Perl_magic_methcall().  */
1076 #define G_WRITING_TO_STDERR 1024 /* Perl_write_to_stderr() is calling
1077                                     Perl_magic_methcall().  */
1078
1079 /* flag bits for PL_in_eval */
1080 #define EVAL_NULL       0       /* not in an eval */
1081 #define EVAL_INEVAL     1       /* some enclosing scope is an eval */
1082 #define EVAL_WARNONLY   2       /* used by yywarn() when calling yyerror() */
1083 #define EVAL_KEEPERR    4       /* set by Perl_call_sv if G_KEEPERR */
1084 #define EVAL_INREQUIRE  8       /* The code is being required. */
1085
1086 /* Support for switching (stack and block) contexts.
1087  * This ensures magic doesn't invalidate local stack and cx pointers.
1088  */
1089
1090 #define PERLSI_UNKNOWN          -1
1091 #define PERLSI_UNDEF            0
1092 #define PERLSI_MAIN             1
1093 #define PERLSI_MAGIC            2
1094 #define PERLSI_SORT             3
1095 #define PERLSI_SIGNAL           4
1096 #define PERLSI_OVERLOAD         5
1097 #define PERLSI_DESTROY          6
1098 #define PERLSI_WARNHOOK         7
1099 #define PERLSI_DIEHOOK          8
1100 #define PERLSI_REQUIRE          9
1101
1102 struct stackinfo {
1103     AV *                si_stack;       /* stack for current runlevel */
1104     PERL_CONTEXT *      si_cxstack;     /* context stack for runlevel */
1105     struct stackinfo *  si_prev;
1106     struct stackinfo *  si_next;
1107     I32                 si_cxix;        /* current context index */
1108     I32                 si_cxmax;       /* maximum allocated index */
1109     I32                 si_type;        /* type of runlevel */
1110     I32                 si_markoff;     /* offset where markstack begins for us.
1111                                          * currently used only with DEBUGGING,
1112                                          * but not #ifdef-ed for bincompat */
1113 };
1114
1115 typedef struct stackinfo PERL_SI;
1116
1117 #define cxstack         (PL_curstackinfo->si_cxstack)
1118 #define cxstack_ix      (PL_curstackinfo->si_cxix)
1119 #define cxstack_max     (PL_curstackinfo->si_cxmax)
1120
1121 #ifdef DEBUGGING
1122 #  define       SET_MARK_OFFSET \
1123     PL_curstackinfo->si_markoff = PL_markstack_ptr - PL_markstack
1124 #else
1125 #  define       SET_MARK_OFFSET NOOP
1126 #endif
1127
1128 #define PUSHSTACKi(type) \
1129     STMT_START {                                                        \
1130         PERL_SI *next = PL_curstackinfo->si_next;                       \
1131         DEBUG_l({                                                       \
1132             int i = 0; PERL_SI *p = PL_curstackinfo;                    \
1133             while (p) { i++; p = p->si_prev; }                          \
1134             Perl_deb(aTHX_ "push STACKINFO %d at %s:%d\n",              \
1135                          i, __FILE__, __LINE__);})                      \
1136         if (!next) {                                                    \
1137             next = new_stackinfo(32, 2048/sizeof(PERL_CONTEXT) - 1);    \
1138             next->si_prev = PL_curstackinfo;                            \
1139             PL_curstackinfo->si_next = next;                            \
1140         }                                                               \
1141         next->si_type = type;                                           \
1142         next->si_cxix = -1;                                             \
1143         AvFILLp(next->si_stack) = 0;                                    \
1144         SWITCHSTACK(PL_curstack,next->si_stack);                        \
1145         PL_curstackinfo = next;                                         \
1146         SET_MARK_OFFSET;                                                \
1147     } STMT_END
1148
1149 #define PUSHSTACK PUSHSTACKi(PERLSI_UNKNOWN)
1150
1151 /* POPSTACK works with PL_stack_sp, so it may need to be bracketed by
1152  * PUTBACK/SPAGAIN to flush/refresh any local SP that may be active */
1153 #define POPSTACK \
1154     STMT_START {                                                        \
1155         dSP;                                                            \
1156         PERL_SI * const prev = PL_curstackinfo->si_prev;                \
1157         DEBUG_l({                                                       \
1158             int i = -1; PERL_SI *p = PL_curstackinfo;                   \
1159             while (p) { i++; p = p->si_prev; }                          \
1160             Perl_deb(aTHX_ "pop  STACKINFO %d at %s:%d\n",              \
1161                          i, __FILE__, __LINE__);})                      \
1162         if (!prev) {                                                    \
1163             PerlIO_printf(Perl_error_log, "panic: POPSTACK\n");         \
1164             my_exit(1);                                                 \
1165         }                                                               \
1166         SWITCHSTACK(PL_curstack,prev->si_stack);                        \
1167         /* don't free prev here, free them all at the END{} */          \
1168         PL_curstackinfo = prev;                                         \
1169     } STMT_END
1170
1171 #define POPSTACK_TO(s) \
1172     STMT_START {                                                        \
1173         while (PL_curstack != s) {                                      \
1174             dounwind(-1);                                               \
1175             POPSTACK;                                                   \
1176         }                                                               \
1177     } STMT_END
1178
1179 #define IN_PERL_COMPILETIME     (PL_curcop == &PL_compiling)
1180 #define IN_PERL_RUNTIME         (PL_curcop != &PL_compiling)
1181
1182 /*
1183 =head1 Multicall Functions
1184
1185 =for apidoc Ams||dMULTICALL
1186 Declare local variables for a multicall. See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1187
1188 =for apidoc Ams||PUSH_MULTICALL
1189 Opening bracket for a lightweight callback.
1190 See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1191
1192 =for apidoc Ams||MULTICALL
1193 Make a lightweight callback. See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1194
1195 =for apidoc Ams||POP_MULTICALL
1196 Closing bracket for a lightweight callback.
1197 See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1198
1199 =cut
1200 */
1201
1202 #define dMULTICALL \
1203     SV **newsp;                 /* set by POPBLOCK */                   \
1204     PERL_CONTEXT *cx;                                                   \
1205     CV *multicall_cv;                                                   \
1206     OP *multicall_cop;                                                  \
1207     bool multicall_oldcatch;                                            \
1208     U8 hasargs = 0              /* used by PUSHSUB */
1209
1210 #define PUSH_MULTICALL(the_cv) \
1211     STMT_START {                                                        \
1212         CV * const _nOnclAshIngNamE_ = the_cv;                          \
1213         CV * const cv = _nOnclAshIngNamE_;                              \
1214         AV * const padlist = CvPADLIST(cv);                             \
1215         ENTER;                                                          \
1216         multicall_oldcatch = CATCH_GET;                                 \
1217         SAVETMPS; SAVEVPTR(PL_op);                                      \
1218         CATCH_SET(TRUE);                                                \
1219         PUSHSTACKi(PERLSI_SORT);                                        \
1220         PUSHBLOCK(cx, CXt_SUB|CXp_MULTICALL, PL_stack_sp);              \
1221         PUSHSUB(cx);                                                    \
1222         if (++CvDEPTH(cv) >= 2) {                                       \
1223             PERL_STACK_OVERFLOW_CHECK();                                \
1224             Perl_pad_push(aTHX_ padlist, CvDEPTH(cv));                  \
1225         }                                                               \
1226         SAVECOMPPAD();                                                  \
1227         PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));                       \
1228         multicall_cv = cv;                                              \
1229         multicall_cop = CvSTART(cv);                                    \
1230     } STMT_END
1231
1232 #define MULTICALL \
1233     STMT_START {                                                        \
1234         PL_op = multicall_cop;                                          \
1235         CALLRUNOPS(aTHX);                                               \
1236     } STMT_END
1237
1238 #define POP_MULTICALL \
1239     STMT_START {                                                        \
1240         if (! --CvDEPTH(multicall_cv))                                  \
1241             LEAVESUB(multicall_cv);                                     \
1242         POPBLOCK(cx,PL_curpm);                                          \
1243         POPSTACK;                                                       \
1244         CATCH_SET(multicall_oldcatch);                                  \
1245         LEAVE;                                                          \
1246         SPAGAIN;                                                        \
1247     } STMT_END
1248
1249 /*
1250  * Local variables:
1251  * c-indentation-style: bsd
1252  * c-basic-offset: 4
1253  * indent-tabs-mode: t
1254  * End:
1255  *
1256  * ex: set ts=8 sts=4 sw=4 noet:
1257  */