This is a live mirror of the Perl 5 development currently hosted at https://github.com/perl/perl5
perldelta: move regex variable fixes into regex section
[perl5.git] / cop.h
1 /*    cop.h
2  *
3  *    Copyright (C) 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
4  *    2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 by Larry Wall and others
5  *
6  *    You may distribute under the terms of either the GNU General Public
7  *    License or the Artistic License, as specified in the README file.
8  *
9  * Control ops (cops) are one of the two ops OP_NEXTSTATE and OP_DBSTATE,
10  * that (loosely speaking) are separate statements.
11  * They hold information important for lexical state and error reporting.
12  * At run time, PL_curcop is set to point to the most recently executed cop,
13  * and thus can be used to determine our current state.
14  */
15
16 /* A jmpenv packages the state required to perform a proper non-local jump.
17  * Note that there is a PL_start_env initialized when perl starts, and
18  * PL_top_env points to this initially, so PL_top_env should always be
19  * non-null.
20  *
21  * Existence of a non-null PL_top_env->je_prev implies it is valid to call
22  * longjmp() at that runlevel (we make sure PL_start_env.je_prev is always
23  * null to ensure this).
24  *
25  * je_mustcatch, when set at any runlevel to TRUE, means eval ops must
26  * establish a local jmpenv to handle exception traps.  Care must be taken
27  * to restore the previous value of je_mustcatch before exiting the
28  * stack frame iff JMPENV_PUSH was not called in that stack frame.
29  * GSAR 97-03-27
30  */
31
32 struct jmpenv {
33     struct jmpenv *     je_prev;
34     Sigjmp_buf          je_buf;         /* only for use if !je_throw */
35     int                 je_ret;         /* last exception thrown */
36     bool                je_mustcatch;   /* need to call longjmp()? */
37 };
38
39 typedef struct jmpenv JMPENV;
40
41 #ifdef OP_IN_REGISTER
42 #define OP_REG_TO_MEM   PL_opsave = op
43 #define OP_MEM_TO_REG   op = PL_opsave
44 #else
45 #define OP_REG_TO_MEM   NOOP
46 #define OP_MEM_TO_REG   NOOP
47 #endif
48
49 /*
50  * How to build the first jmpenv.
51  *
52  * top_env needs to be non-zero. It points to an area
53  * in which longjmp() stuff is stored, as C callstack
54  * info there at least is thread specific this has to
55  * be per-thread. Otherwise a 'die' in a thread gives
56  * that thread the C stack of last thread to do an eval {}!
57  */
58
59 #define JMPENV_BOOTSTRAP \
60     STMT_START {                                \
61         Zero(&PL_start_env, 1, JMPENV);         \
62         PL_start_env.je_ret = -1;               \
63         PL_start_env.je_mustcatch = TRUE;       \
64         PL_top_env = &PL_start_env;             \
65     } STMT_END
66
67 /*
68  *   PERL_FLEXIBLE_EXCEPTIONS
69  * 
70  * All the flexible exceptions code has been removed.
71  * See the following threads for details:
72  *
73  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/2004-07/msg00378.html
74  * 
75  * Joshua's original patches (which weren't applied) and discussion:
76  * 
77  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01396.html
78  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01489.html
79  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01491.html
80  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg01608.html
81  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg02144.html
82  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1998-02/msg02998.html
83  * 
84  * Chip's reworked patch and discussion:
85  * 
86  *   http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/1999-03/msg00520.html
87  * 
88  * The flaw in these patches (which went unnoticed at the time) was
89  * that they moved some code that could potentially die() out of the
90  * region protected by the setjmp()s.  This caused exceptions within
91  * END blocks and such to not be handled by the correct setjmp().
92  * 
93  * The original patches that introduces flexible exceptions were:
94  *
95  * http://perl5.git.perl.org/perl.git/commit/312caa8e97f1c7ee342a9895c2f0e749625b4929
96  * http://perl5.git.perl.org/perl.git/commit/14dd3ad8c9bf82cf09798a22cc89a9862dfd6d1a                                        
97  *  
98  */
99
100 #define dJMPENV         JMPENV cur_env
101
102 #define JMPENV_PUSH(v) \
103     STMT_START {                                                        \
104         DEBUG_l({                                                       \
105             int i = 0; JMPENV *p = PL_top_env;                          \
106             while (p) { i++; p = p->je_prev; }                          \
107             Perl_deb(aTHX_ "JUMPENV_PUSH level=%d at %s:%d\n",          \
108                          i,  __FILE__, __LINE__);})                     \
109         cur_env.je_prev = PL_top_env;                                   \
110         OP_REG_TO_MEM;                                                  \
111         cur_env.je_ret = PerlProc_setjmp(cur_env.je_buf, SCOPE_SAVES_SIGNAL_MASK);              \
112         OP_MEM_TO_REG;                                                  \
113         PL_top_env = &cur_env;                                          \
114         cur_env.je_mustcatch = FALSE;                                   \
115         (v) = cur_env.je_ret;                                           \
116     } STMT_END
117
118 #define JMPENV_POP \
119     STMT_START {                                                        \
120         DEBUG_l({                                                       \
121             int i = -1; JMPENV *p = PL_top_env;                         \
122             while (p) { i++; p = p->je_prev; }                          \
123             Perl_deb(aTHX_ "JUMPENV_POP level=%d at %s:%d\n",           \
124                          i, __FILE__, __LINE__);})                      \
125         assert(PL_top_env == &cur_env);                                 \
126         PL_top_env = cur_env.je_prev;                                   \
127     } STMT_END
128
129 #define JMPENV_JUMP(v) \
130     STMT_START {                                                \
131         DEBUG_l({                                               \
132             int i = -1; JMPENV *p = PL_top_env;                 \
133             while (p) { i++; p = p->je_prev; }                  \
134             Perl_deb(aTHX_ "JUMPENV_JUMP(%d) level=%d at %s:%d\n", \
135                          (int)v, i, __FILE__, __LINE__);})      \
136         OP_REG_TO_MEM;                                          \
137         if (PL_top_env->je_prev)                                \
138             PerlProc_longjmp(PL_top_env->je_buf, (v));          \
139         if ((v) == 2)                                           \
140             PerlProc_exit(STATUS_EXIT);                         \
141         PerlIO_printf(PerlIO_stderr(), "panic: top_env, v=%d\n", (int)v); \
142         PerlProc_exit(1);                                       \
143     } STMT_END
144
145 #define CATCH_GET               (PL_top_env->je_mustcatch)
146 #define CATCH_SET(v) \
147     STMT_START {                                                        \
148         DEBUG_l(                                                        \
149             Perl_deb(aTHX_                                              \
150                 "JUMPLEVEL set catch %d => %d (for %p) at %s:%d\n",     \
151                  PL_top_env->je_mustcatch, v, (void*)PL_top_env,        \
152                  __FILE__, __LINE__);)                                  \
153         PL_top_env->je_mustcatch = (v);                                 \
154     } STMT_END
155
156 /*
157 =head1 COP Hint Hashes
158 */
159
160 typedef struct refcounted_he COPHH;
161
162 #define COPHH_KEY_UTF8 REFCOUNTED_HE_KEY_UTF8
163
164 /*
165 =for apidoc Amx|SV *|cophh_fetch_pvn|const COPHH *cophh|const char *keypv|STRLEN keylen|U32 hash|U32 flags
166
167 Look up the entry in the cop hints hash I<cophh> with the key specified by
168 I<keypv> and I<keylen>.  If I<flags> has the C<COPHH_KEY_UTF8> bit set,
169 the key octets are interpreted as UTF-8, otherwise they are interpreted
170 as Latin-1.  I<hash> is a precomputed hash of the key string, or zero if
171 it has not been precomputed.  Returns a mortal scalar copy of the value
172 associated with the key, or C<&PL_sv_placeholder> if there is no value
173 associated with the key.
174
175 =cut
176 */
177
178 #define cophh_fetch_pvn(cophh, keypv, keylen, hash, flags) \
179     Perl_refcounted_he_fetch_pvn(aTHX_ cophh, keypv, keylen, hash, flags)
180
181 /*
182 =for apidoc Amx|SV *|cophh_fetch_pvs|const COPHH *cophh|const char *key|U32 flags
183
184 Like L</cophh_fetch_pvn>, but takes a literal string instead of a
185 string/length pair, and no precomputed hash.
186
187 =cut
188 */
189
190 #define cophh_fetch_pvs(cophh, key, flags) \
191     Perl_refcounted_he_fetch_pvn(aTHX_ cophh, STR_WITH_LEN(key), 0, flags)
192
193 /*
194 =for apidoc Amx|SV *|cophh_fetch_pv|const COPHH *cophh|const char *key|U32 hash|U32 flags
195
196 Like L</cophh_fetch_pvn>, but takes a nul-terminated string instead of
197 a string/length pair.
198
199 =cut
200 */
201
202 #define cophh_fetch_pv(cophh, key, hash, flags) \
203     Perl_refcounted_he_fetch_pv(aTHX_ cophh, key, hash, flags)
204
205 /*
206 =for apidoc Amx|SV *|cophh_fetch_sv|const COPHH *cophh|SV *key|U32 hash|U32 flags
207
208 Like L</cophh_fetch_pvn>, but takes a Perl scalar instead of a
209 string/length pair.
210
211 =cut
212 */
213
214 #define cophh_fetch_sv(cophh, key, hash, flags) \
215     Perl_refcounted_he_fetch_sv(aTHX_ cophh, key, hash, flags)
216
217 /*
218 =for apidoc Amx|HV *|cophh_2hv|const COPHH *cophh|U32 flags
219
220 Generates and returns a standard Perl hash representing the full set of
221 key/value pairs in the cop hints hash I<cophh>.  I<flags> is currently
222 unused and must be zero.
223
224 =cut
225 */
226
227 #define cophh_2hv(cophh, flags) \
228     Perl_refcounted_he_chain_2hv(aTHX_ cophh, flags)
229
230 /*
231 =for apidoc Amx|COPHH *|cophh_copy|COPHH *cophh
232
233 Make and return a complete copy of the cop hints hash I<cophh>.
234
235 =cut
236 */
237
238 #define cophh_copy(cophh) Perl_refcounted_he_inc(aTHX_ cophh)
239
240 /*
241 =for apidoc Amx|void|cophh_free|COPHH *cophh
242
243 Discard the cop hints hash I<cophh>, freeing all resources associated
244 with it.
245
246 =cut
247 */
248
249 #define cophh_free(cophh) Perl_refcounted_he_free(aTHX_ cophh)
250
251 /*
252 =for apidoc Amx|COPHH *|cophh_new_empty
253
254 Generate and return a fresh cop hints hash containing no entries.
255
256 =cut
257 */
258
259 #define cophh_new_empty() ((COPHH *)NULL)
260
261 /*
262 =for apidoc Amx|COPHH *|cophh_store_pvn|COPHH *cophh|const char *keypv|STRLEN keylen|U32 hash|SV *value|U32 flags
263
264 Stores a value, associated with a key, in the cop hints hash I<cophh>,
265 and returns the modified hash.  The returned hash pointer is in general
266 not the same as the hash pointer that was passed in.  The input hash is
267 consumed by the function, and the pointer to it must not be subsequently
268 used.  Use L</cophh_copy> if you need both hashes.
269
270 The key is specified by I<keypv> and I<keylen>.  If I<flags> has the
271 C<COPHH_KEY_UTF8> bit set, the key octets are interpreted as UTF-8,
272 otherwise they are interpreted as Latin-1.  I<hash> is a precomputed
273 hash of the key string, or zero if it has not been precomputed.
274
275 I<value> is the scalar value to store for this key.  I<value> is copied
276 by this function, which thus does not take ownership of any reference
277 to it, and later changes to the scalar will not be reflected in the
278 value visible in the cop hints hash.  Complex types of scalar will not
279 be stored with referential integrity, but will be coerced to strings.
280
281 =cut
282 */
283
284 #define cophh_store_pvn(cophh, keypv, keylen, hash, value, flags) \
285     Perl_refcounted_he_new_pvn(aTHX_ cophh, keypv, keylen, hash, value, flags)
286
287 /*
288 =for apidoc Amx|COPHH *|cophh_store_pvs|const COPHH *cophh|const char *key|SV *value|U32 flags
289
290 Like L</cophh_store_pvn>, but takes a literal string instead of a
291 string/length pair, and no precomputed hash.
292
293 =cut
294 */
295
296 #define cophh_store_pvs(cophh, key, value, flags) \
297     Perl_refcounted_he_new_pvn(aTHX_ cophh, STR_WITH_LEN(key), 0, value, flags)
298
299 /*
300 =for apidoc Amx|COPHH *|cophh_store_pv|const COPHH *cophh|const char *key|U32 hash|SV *value|U32 flags
301
302 Like L</cophh_store_pvn>, but takes a nul-terminated string instead of
303 a string/length pair.
304
305 =cut
306 */
307
308 #define cophh_store_pv(cophh, key, hash, value, flags) \
309     Perl_refcounted_he_new_pv(aTHX_ cophh, key, hash, value, flags)
310
311 /*
312 =for apidoc Amx|COPHH *|cophh_store_sv|const COPHH *cophh|SV *key|U32 hash|SV *value|U32 flags
313
314 Like L</cophh_store_pvn>, but takes a Perl scalar instead of a
315 string/length pair.
316
317 =cut
318 */
319
320 #define cophh_store_sv(cophh, key, hash, value, flags) \
321     Perl_refcounted_he_new_sv(aTHX_ cophh, key, hash, value, flags)
322
323 /*
324 =for apidoc Amx|COPHH *|cophh_delete_pvn|COPHH *cophh|const char *keypv|STRLEN keylen|U32 hash|U32 flags
325
326 Delete a key and its associated value from the cop hints hash I<cophh>,
327 and returns the modified hash.  The returned hash pointer is in general
328 not the same as the hash pointer that was passed in.  The input hash is
329 consumed by the function, and the pointer to it must not be subsequently
330 used.  Use L</cophh_copy> if you need both hashes.
331
332 The key is specified by I<keypv> and I<keylen>.  If I<flags> has the
333 C<COPHH_KEY_UTF8> bit set, the key octets are interpreted as UTF-8,
334 otherwise they are interpreted as Latin-1.  I<hash> is a precomputed
335 hash of the key string, or zero if it has not been precomputed.
336
337 =cut
338 */
339
340 #define cophh_delete_pvn(cophh, keypv, keylen, hash, flags) \
341     Perl_refcounted_he_new_pvn(aTHX_ cophh, keypv, keylen, hash, \
342         (SV *)NULL, flags)
343
344 /*
345 =for apidoc Amx|COPHH *|cophh_delete_pvs|const COPHH *cophh|const char *key|U32 flags
346
347 Like L</cophh_delete_pvn>, but takes a literal string instead of a
348 string/length pair, and no precomputed hash.
349
350 =cut
351 */
352
353 #define cophh_delete_pvs(cophh, key, flags) \
354     Perl_refcounted_he_new_pvn(aTHX_ cophh, STR_WITH_LEN(key), 0, \
355         (SV *)NULL, flags)
356
357 /*
358 =for apidoc Amx|COPHH *|cophh_delete_pv|const COPHH *cophh|const char *key|U32 hash|U32 flags
359
360 Like L</cophh_delete_pvn>, but takes a nul-terminated string instead of
361 a string/length pair.
362
363 =cut
364 */
365
366 #define cophh_delete_pv(cophh, key, hash, flags) \
367     Perl_refcounted_he_new_pv(aTHX_ cophh, key, hash, (SV *)NULL, flags)
368
369 /*
370 =for apidoc Amx|COPHH *|cophh_delete_sv|const COPHH *cophh|SV *key|U32 hash|U32 flags
371
372 Like L</cophh_delete_pvn>, but takes a Perl scalar instead of a
373 string/length pair.
374
375 =cut
376 */
377
378 #define cophh_delete_sv(cophh, key, hash, flags) \
379     Perl_refcounted_he_new_sv(aTHX_ cophh, key, hash, (SV *)NULL, flags)
380
381 #include "mydtrace.h"
382
383 struct cop {
384     BASEOP
385     /* On LP64 putting this here takes advantage of the fact that BASEOP isn't
386        an exact multiple of 8 bytes to save structure padding.  */
387     line_t      cop_line;       /* line # of this command */
388     /* label for this construct is now stored in cop_hints_hash */
389 #ifdef USE_ITHREADS
390     char *      cop_stashpv;    /* package line was compiled in */
391     char *      cop_file;       /* file name the following line # is from */
392     I32         cop_stashlen;   /* negative for UTF8 */
393 #else
394     HV *        cop_stash;      /* package line was compiled in */
395     GV *        cop_filegv;     /* file the following line # is from */
396 #endif
397     U32         cop_hints;      /* hints bits from pragmata */
398     U32         cop_seq;        /* parse sequence number */
399     /* Beware. mg.c and warnings.pl assume the type of this is STRLEN *:  */
400     STRLEN *    cop_warnings;   /* lexical warnings bitmask */
401     /* compile time state of %^H.  See the comment in op.c for how this is
402        used to recreate a hash to return from caller.  */
403     COPHH *     cop_hints_hash;
404 };
405
406 #ifdef USE_ITHREADS
407 #  define CopFILE(c)            ((c)->cop_file)
408 #  define CopFILEGV(c)          (CopFILE(c) \
409                                  ? gv_fetchfile(CopFILE(c)) : NULL)
410                                  
411 #  ifdef NETWARE
412 #    define CopFILE_set(c,pv)   ((c)->cop_file = savepv(pv))
413 #    define CopFILE_setn(c,pv,l)  ((c)->cop_file = savepv((pv),(l)))
414 #  else
415 #    define CopFILE_set(c,pv)   ((c)->cop_file = savesharedpv(pv))
416 #    define CopFILE_setn(c,pv,l)  ((c)->cop_file = savesharedpvn((pv),(l)))
417 #  endif
418
419 #  define CopFILESV(c)          (CopFILE(c) \
420                                  ? GvSV(gv_fetchfile(CopFILE(c))) : NULL)
421 #  define CopFILEAV(c)          (CopFILE(c) \
422                                  ? GvAV(gv_fetchfile(CopFILE(c))) : NULL)
423 #  ifdef DEBUGGING
424 #    define CopFILEAVx(c)       (assert(CopFILE(c)), \
425                                    GvAV(gv_fetchfile(CopFILE(c))))
426 #  else
427 #    define CopFILEAVx(c)       (GvAV(gv_fetchfile(CopFILE(c))))
428 #  endif
429 #  define CopSTASHPV(c)         ((c)->cop_stashpv)
430
431 #  ifdef NETWARE
432 #    define CopSTASHPV_set(c,pv,n)      ((c)->cop_stashpv = \
433                                            ((pv) ? savepvn(pv,n) : NULL))
434 #  else
435 #    define CopSTASHPV_set(c,pv,n)      ((c)->cop_stashpv = (pv) \
436                                             ? savesharedpvn(pv,n) : NULL)
437 #  endif
438
439 #  define CopSTASH_len_set(c,n) ((c)->cop_stashlen = (n))
440 #  define CopSTASH_len(c)       ((c)->cop_stashlen)
441
442 #  define CopSTASH(c)          (CopSTASHPV(c)                                 \
443                                 ? gv_stashpvn(CopSTASHPV(c),              \
444                                     CopSTASH_len(c) < 0                   \
445                                         ? -CopSTASH_len(c)                \
446                                         :  CopSTASH_len(c),               \
447                                     GV_ADD|SVf_UTF8*(CopSTASH_len(c) < 0) \
448                                   )                                       \
449                                  : NULL)
450 #  define CopSTASH_set(c,hv)   (CopSTASHPV_set(c,                       \
451                                     (hv) ? HvNAME_get(hv) : NULL,       \
452                                     (hv) ? HvNAMELEN(hv)  : 0),         \
453                                 CopSTASH_len_set(c,                     \
454                                     (hv) ? HvNAMEUTF8(hv)               \
455                                             ? -HvNAMELEN(hv)            \
456                                             :  HvNAMELEN(hv)            \
457                                          : 0))
458 #  define CopSTASH_eq(c,hv)     ((hv) && stashpv_hvname_match(c,hv))
459 #  ifdef NETWARE
460 #    define CopSTASH_free(c) SAVECOPSTASH_FREE(c)
461 #    define CopFILE_free(c) SAVECOPFILE_FREE(c)
462 #  else
463 #    define CopSTASH_free(c)    PerlMemShared_free(CopSTASHPV(c))
464 #    define CopFILE_free(c)     (PerlMemShared_free(CopFILE(c)),(CopFILE(c) = NULL))
465 #  endif
466 #else
467 #  define CopFILEGV(c)          ((c)->cop_filegv)
468 #  define CopFILEGV_set(c,gv)   ((c)->cop_filegv = (GV*)SvREFCNT_inc(gv))
469 #  define CopFILE_set(c,pv)     CopFILEGV_set((c), gv_fetchfile(pv))
470 #  define CopFILE_setn(c,pv,l)  CopFILEGV_set((c), gv_fetchfile_flags((pv),(l),0))
471 #  define CopFILESV(c)          (CopFILEGV(c) ? GvSV(CopFILEGV(c)) : NULL)
472 #  define CopFILEAV(c)          (CopFILEGV(c) ? GvAV(CopFILEGV(c)) : NULL)
473 #  ifdef DEBUGGING
474 #    define CopFILEAVx(c)       (assert(CopFILEGV(c)), GvAV(CopFILEGV(c)))
475 #  else
476 #    define CopFILEAVx(c)       (GvAV(CopFILEGV(c)))
477 # endif
478 #  define CopFILE(c)            (CopFILEGV(c) && GvSV(CopFILEGV(c)) \
479                                     ? SvPVX(GvSV(CopFILEGV(c))) : NULL)
480 #  define CopSTASH(c)           ((c)->cop_stash)
481 #  define CopSTASH_set(c,hv)    ((c)->cop_stash = (hv))
482 #  define CopSTASHPV(c)         (CopSTASH(c) ? HvNAME_get(CopSTASH(c)) : NULL)
483    /* cop_stash is not refcounted */
484 #  define CopSTASHPV_set(c,pv)  CopSTASH_set((c), gv_stashpv(pv,GV_ADD))
485 #  define CopSTASH_eq(c,hv)     (CopSTASH(c) == (hv))
486 #  define CopSTASH_free(c)      
487 #  define CopFILE_free(c)       (SvREFCNT_dec(CopFILEGV(c)),(CopFILEGV(c) = NULL))
488
489 #endif /* USE_ITHREADS */
490
491 #define CopHINTHASH_get(c)      ((COPHH*)((c)->cop_hints_hash))
492 #define CopHINTHASH_set(c,h)    ((c)->cop_hints_hash = (h))
493
494 /*
495 =head1 COP Hint Reading
496 */
497
498 /*
499 =for apidoc Am|SV *|cop_hints_fetch_pvn|const COP *cop|const char *keypv|STRLEN keylen|U32 hash|U32 flags
500
501 Look up the hint entry in the cop I<cop> with the key specified by
502 I<keypv> and I<keylen>.  If I<flags> has the C<COPHH_KEY_UTF8> bit set,
503 the key octets are interpreted as UTF-8, otherwise they are interpreted
504 as Latin-1.  I<hash> is a precomputed hash of the key string, or zero if
505 it has not been precomputed.  Returns a mortal scalar copy of the value
506 associated with the key, or C<&PL_sv_placeholder> if there is no value
507 associated with the key.
508
509 =cut
510 */
511
512 #define cop_hints_fetch_pvn(cop, keypv, keylen, hash, flags) \
513     cophh_fetch_pvn(CopHINTHASH_get(cop), keypv, keylen, hash, flags)
514
515 /*
516 =for apidoc Am|SV *|cop_hints_fetch_pvs|const COP *cop|const char *key|U32 flags
517
518 Like L</cop_hints_fetch_pvn>, but takes a literal string instead of a
519 string/length pair, and no precomputed hash.
520
521 =cut
522 */
523
524 #define cop_hints_fetch_pvs(cop, key, flags) \
525     cophh_fetch_pvs(CopHINTHASH_get(cop), key, flags)
526
527 /*
528 =for apidoc Am|SV *|cop_hints_fetch_pv|const COP *cop|const char *key|U32 hash|U32 flags
529
530 Like L</cop_hints_fetch_pvn>, but takes a nul-terminated string instead
531 of a string/length pair.
532
533 =cut
534 */
535
536 #define cop_hints_fetch_pv(cop, key, hash, flags) \
537     cophh_fetch_pv(CopHINTHASH_get(cop), key, hash, flags)
538
539 /*
540 =for apidoc Am|SV *|cop_hints_fetch_sv|const COP *cop|SV *key|U32 hash|U32 flags
541
542 Like L</cop_hints_fetch_pvn>, but takes a Perl scalar instead of a
543 string/length pair.
544
545 =cut
546 */
547
548 #define cop_hints_fetch_sv(cop, key, hash, flags) \
549     cophh_fetch_sv(CopHINTHASH_get(cop), key, hash, flags)
550
551 /*
552 =for apidoc Am|HV *|cop_hints_2hv|const COP *cop|U32 flags
553
554 Generates and returns a standard Perl hash representing the full set of
555 hint entries in the cop I<cop>.  I<flags> is currently unused and must
556 be zero.
557
558 =cut
559 */
560
561 #define cop_hints_2hv(cop, flags) \
562     cophh_2hv(CopHINTHASH_get(cop), flags)
563
564 #define CopLABEL(c)  Perl_cop_fetch_label(aTHX_ (c), NULL, NULL)
565 #define CopLABEL_len(c,len)  Perl_cop_fetch_label(aTHX_ (c), len, NULL)
566 #define CopLABEL_len_flags(c,len,flags)  Perl_cop_fetch_label(aTHX_ (c), len, flags)
567 #define CopLABEL_alloc(pv)      ((pv)?savepv(pv):NULL)
568
569 #define CopSTASH_ne(c,hv)       (!CopSTASH_eq(c,hv))
570 #define CopLINE(c)              ((c)->cop_line)
571 #define CopLINE_inc(c)          (++CopLINE(c))
572 #define CopLINE_dec(c)          (--CopLINE(c))
573 #define CopLINE_set(c,l)        (CopLINE(c) = (l))
574
575 /* OutCopFILE() is CopFILE for output (caller, die, warn, etc.) */
576 #define OutCopFILE(c) CopFILE(c)
577
578 /* FIXME NATIVE_HINTS if this is changed from op_private (see perl.h)  */
579 #define CopHINTS_get(c)         ((c)->cop_hints + 0)
580 #define CopHINTS_set(c, h)      STMT_START {                            \
581                                     (c)->cop_hints = (h);               \
582                                 } STMT_END
583
584 /*
585  * Here we have some enormously heavy (or at least ponderous) wizardry.
586  */
587
588 /* subroutine context */
589 struct block_sub {
590     OP *        retop;  /* op to execute on exit from sub */
591     /* Above here is the same for sub, format and eval.  */
592     CV *        cv;
593     /* Above here is the same for sub and format.  */
594     AV *        savearray;
595     AV *        argarray;
596     I32         olddepth;
597     PAD         *oldcomppad;
598 };
599
600
601 /* format context */
602 struct block_format {
603     OP *        retop;  /* op to execute on exit from sub */
604     /* Above here is the same for sub, format and eval.  */
605     CV *        cv;
606     /* Above here is the same for sub and format.  */
607     GV *        gv;
608     GV *        dfoutgv;
609 };
610
611 /* base for the next two macros. Don't use directly.
612  * Note that the refcnt of the cv is incremented twice;  The CX one is
613  * decremented by LEAVESUB, the other by LEAVE. */
614
615 #define PUSHSUB_BASE(cx)                                                \
616         ENTRY_PROBE(GvENAME(CvGV(cv)),                                  \
617                 CopFILE((const COP *)CvSTART(cv)),                      \
618                 CopLINE((const COP *)CvSTART(cv)),                      \
619                 CopSTASHPV((const COP *)CvSTART(cv)));                  \
620                                                                         \
621         cx->blk_sub.cv = cv;                                            \
622         cx->blk_sub.olddepth = CvDEPTH(cv);                             \
623         cx->cx_type |= (hasargs) ? CXp_HASARGS : 0;                     \
624         cx->blk_sub.retop = NULL;                                       \
625         if (!CvDEPTH(cv)) {                                             \
626             SvREFCNT_inc_simple_void_NN(cv);                            \
627             SvREFCNT_inc_simple_void_NN(cv);                            \
628             SAVEFREESV(cv);                                             \
629         }
630
631
632 #define PUSHSUB(cx)                                                     \
633     {                                                                   \
634         /* If the context is indeterminate, then only the lvalue */     \
635         /* flags that the caller also has are applicable.        */     \
636         U8 phlags =                                                     \
637            (PL_op->op_flags & OPf_WANT)                                 \
638                ? OPpENTERSUB_LVAL_MASK                                  \
639                : !(PL_op->op_private & OPpENTERSUB_LVAL_MASK)           \
640                    ? 0 : Perl_was_lvalue_sub(aTHX);                     \
641         PUSHSUB_BASE(cx)                                                \
642         cx->blk_u16 = PL_op->op_private &                               \
643                           (phlags|OPpDEREF);                            \
644     }
645
646 /* variant for use by OP_DBSTATE, where op_private holds hint bits */
647 #define PUSHSUB_DB(cx)                                                  \
648         PUSHSUB_BASE(cx)                                                \
649         cx->blk_u16 = 0;
650
651
652 #define PUSHFORMAT(cx, retop)                                           \
653         cx->blk_format.cv = cv;                                         \
654         cx->blk_format.gv = gv;                                         \
655         cx->blk_format.retop = (retop);                                 \
656         cx->blk_format.dfoutgv = PL_defoutgv;                           \
657         SvREFCNT_inc_void(cx->blk_format.dfoutgv)
658
659 #define POP_SAVEARRAY()                                         \
660     STMT_START {                                                        \
661         SvREFCNT_dec(GvAV(PL_defgv));                                   \
662         GvAV(PL_defgv) = cx->blk_sub.savearray;                         \
663     } STMT_END
664
665 /* junk in @_ spells trouble when cloning CVs and in pp_caller(), so don't
666  * leave any (a fast av_clear(ary), basically) */
667 #define CLEAR_ARGARRAY(ary) \
668     STMT_START {                                                        \
669         AvMAX(ary) += AvARRAY(ary) - AvALLOC(ary);                      \
670         AvARRAY(ary) = AvALLOC(ary);                                    \
671         AvFILLp(ary) = -1;                                              \
672     } STMT_END
673
674 #define POPSUB(cx,sv)                                                   \
675     STMT_START {                                                        \
676         RETURN_PROBE(GvENAME(CvGV((const CV*)cx->blk_sub.cv)),          \
677                 CopFILE((COP*)CvSTART((const CV*)cx->blk_sub.cv)),      \
678                 CopLINE((COP*)CvSTART((const CV*)cx->blk_sub.cv)),      \
679                 CopSTASHPV((COP*)CvSTART((const CV*)cx->blk_sub.cv)));  \
680                                                                         \
681         if (CxHASARGS(cx)) {                                            \
682             POP_SAVEARRAY();                                            \
683             /* abandon @_ if it got reified */                          \
684             if (AvREAL(cx->blk_sub.argarray)) {                         \
685                 const SSize_t fill = AvFILLp(cx->blk_sub.argarray);     \
686                 SvREFCNT_dec(cx->blk_sub.argarray);                     \
687                 cx->blk_sub.argarray = newAV();                         \
688                 av_extend(cx->blk_sub.argarray, fill);                  \
689                 AvREIFY_only(cx->blk_sub.argarray);                     \
690                 CX_CURPAD_SV(cx->blk_sub, 0) = MUTABLE_SV(cx->blk_sub.argarray); \
691             }                                                           \
692             else {                                                      \
693                 CLEAR_ARGARRAY(cx->blk_sub.argarray);                   \
694             }                                                           \
695         }                                                               \
696         sv = MUTABLE_SV(cx->blk_sub.cv);                                \
697         if (sv && (CvDEPTH((const CV*)sv) = cx->blk_sub.olddepth))      \
698             sv = NULL;                                          \
699     } STMT_END
700
701 #define LEAVESUB(sv)                                                    \
702     STMT_START {                                                        \
703         if (sv)                                                         \
704             SvREFCNT_dec(sv);                                           \
705     } STMT_END
706
707 #define POPFORMAT(cx)                                                   \
708         setdefout(cx->blk_format.dfoutgv);                              \
709         SvREFCNT_dec(cx->blk_format.dfoutgv);
710
711 /* eval context */
712 struct block_eval {
713     OP *        retop;  /* op to execute on exit from eval */
714     /* Above here is the same for sub, format and eval.  */
715     SV *        old_namesv;
716     OP *        old_eval_root;
717     SV *        cur_text;
718     CV *        cv;
719     JMPENV *    cur_top_env; /* value of PL_top_env when eval CX created */
720 };
721
722 /* If we ever need more than 512 op types, change the shift from 7.
723    blku_gimme is actually also only 2 bits, so could be merged with something.
724 */
725
726 #define CxOLD_IN_EVAL(cx)       (((cx)->blk_u16) & 0x7F)
727 #define CxOLD_OP_TYPE(cx)       (((cx)->blk_u16) >> 7)
728
729 #define PUSHEVAL(cx,n)                                                  \
730     STMT_START {                                                        \
731         assert(!(PL_in_eval & ~0x7F));                                  \
732         assert(!(PL_op->op_type & ~0x1FF));                             \
733         cx->blk_u16 = (PL_in_eval & 0x7F) | ((U16)PL_op->op_type << 7); \
734         cx->blk_eval.old_namesv = (n ? newSVpv(n,0) : NULL);            \
735         cx->blk_eval.old_eval_root = PL_eval_root;                      \
736         cx->blk_eval.cur_text = PL_parser ? PL_parser->linestr : NULL;  \
737         cx->blk_eval.cv = NULL; /* set by doeval(), as applicable */    \
738         cx->blk_eval.retop = NULL;                                      \
739         cx->blk_eval.cur_top_env = PL_top_env;                          \
740     } STMT_END
741
742 #define POPEVAL(cx)                                                     \
743     STMT_START {                                                        \
744         PL_in_eval = CxOLD_IN_EVAL(cx);                                 \
745         optype = CxOLD_OP_TYPE(cx);                                     \
746         PL_eval_root = cx->blk_eval.old_eval_root;                      \
747         if (cx->blk_eval.old_namesv)                                    \
748             sv_2mortal(cx->blk_eval.old_namesv);                        \
749     } STMT_END
750
751 /* loop context */
752 struct block_loop {
753     I32         resetsp;
754     LOOP *      my_op;  /* My op, that contains redo, next and last ops.  */
755     union {     /* different ways of locating the iteration variable */
756         SV      **svp;
757         GV      *gv;
758         PAD     *oldcomppad; /* only used in ITHREADS */
759     } itervar_u;
760     union {
761         struct { /* valid if type is LOOP_FOR or LOOP_PLAIN (but {NULL,0})*/
762             AV * ary; /* use the stack if this is NULL */
763             IV ix;
764         } ary;
765         struct { /* valid if type is LOOP_LAZYIV */
766             IV cur;
767             IV end;
768         } lazyiv;
769         struct { /* valid if type if LOOP_LAZYSV */
770             SV * cur;
771             SV * end; /* maxiumum value (or minimum in reverse) */
772         } lazysv;
773     } state_u;
774 };
775
776 #ifdef USE_ITHREADS
777 #  define CxITERVAR_PADSV(c) \
778         &CX_CURPAD_SV( (c)->blk_loop.itervar_u, (c)->blk_loop.my_op->op_targ)
779 #else
780 #  define CxITERVAR_PADSV(c) ((c)->blk_loop.itervar_u.svp)
781 #endif
782
783 #define CxITERVAR(c)                                                    \
784         ((c)->blk_loop.itervar_u.oldcomppad                             \
785          ? (CxPADLOOP(c)                                                \
786             ? CxITERVAR_PADSV(c)                                        \
787             : &GvSV((c)->blk_loop.itervar_u.gv))                        \
788          : (SV**)NULL)
789
790 #define CxLABEL(c)      (0 + CopLABEL((c)->blk_oldcop))
791 #define CxLABEL_len(c,len)      (0 + CopLABEL_len((c)->blk_oldcop, len))
792 #define CxLABEL_len_flags(c,len,flags)  (0 + CopLABEL_len_flags((c)->blk_oldcop, len, flags))
793 #define CxHASARGS(c)    (((c)->cx_type & CXp_HASARGS) == CXp_HASARGS)
794 #define CxLVAL(c)       (0 + (c)->blk_u16)
795
796 #define PUSHLOOP_PLAIN(cx, s)                                           \
797         cx->blk_loop.resetsp = s - PL_stack_base;                       \
798         cx->blk_loop.my_op = cLOOP;                                     \
799         cx->blk_loop.state_u.ary.ary = NULL;                            \
800         cx->blk_loop.state_u.ary.ix = 0;                                \
801         cx->blk_loop.itervar_u.svp = NULL;
802
803 #define PUSHLOOP_FOR(cx, ivar, s)                                       \
804         cx->blk_loop.resetsp = s - PL_stack_base;                       \
805         cx->blk_loop.my_op = cLOOP;                                     \
806         cx->blk_loop.state_u.ary.ary = NULL;                            \
807         cx->blk_loop.state_u.ary.ix = 0;                                \
808         cx->blk_loop.itervar_u.svp = (SV**)(ivar);
809
810 #define POPLOOP(cx)                                                     \
811         if (CxTYPE(cx) == CXt_LOOP_LAZYSV) {                            \
812             SvREFCNT_dec(cx->blk_loop.state_u.lazysv.cur);              \
813             SvREFCNT_dec(cx->blk_loop.state_u.lazysv.end);              \
814         }                                                               \
815         if (CxTYPE(cx) == CXt_LOOP_FOR)                                 \
816             SvREFCNT_dec(cx->blk_loop.state_u.ary.ary);
817
818 /* given/when context */
819 struct block_givwhen {
820         OP *leave_op;
821 };
822
823 #define PUSHGIVEN(cx)                                                   \
824         cx->blk_givwhen.leave_op = cLOGOP->op_other;
825
826 #define PUSHWHEN PUSHGIVEN
827
828 /* context common to subroutines, evals and loops */
829 struct block {
830     U8          blku_type;      /* what kind of context this is */
831     U8          blku_gimme;     /* is this block running in list context? */
832     U16         blku_u16;       /* used by block_sub and block_eval (so far) */
833     I32         blku_oldsp;     /* stack pointer to copy stuff down to */
834     COP *       blku_oldcop;    /* old curcop pointer */
835     I32         blku_oldmarksp; /* mark stack index */
836     I32         blku_oldscopesp;        /* scope stack index */
837     PMOP *      blku_oldpm;     /* values of pattern match vars */
838
839     union {
840         struct block_sub        blku_sub;
841         struct block_format     blku_format;
842         struct block_eval       blku_eval;
843         struct block_loop       blku_loop;
844         struct block_givwhen    blku_givwhen;
845     } blk_u;
846 };
847 #define blk_oldsp       cx_u.cx_blk.blku_oldsp
848 #define blk_oldcop      cx_u.cx_blk.blku_oldcop
849 #define blk_oldmarksp   cx_u.cx_blk.blku_oldmarksp
850 #define blk_oldscopesp  cx_u.cx_blk.blku_oldscopesp
851 #define blk_oldpm       cx_u.cx_blk.blku_oldpm
852 #define blk_gimme       cx_u.cx_blk.blku_gimme
853 #define blk_u16         cx_u.cx_blk.blku_u16
854 #define blk_sub         cx_u.cx_blk.blk_u.blku_sub
855 #define blk_format      cx_u.cx_blk.blk_u.blku_format
856 #define blk_eval        cx_u.cx_blk.blk_u.blku_eval
857 #define blk_loop        cx_u.cx_blk.blk_u.blku_loop
858 #define blk_givwhen     cx_u.cx_blk.blk_u.blku_givwhen
859
860 #define DEBUG_CX(action)                                                \
861     DEBUG_l(                                                            \
862         Perl_deb(aTHX_ "CX %ld %s %s (scope %ld,%ld) at %s:%d\n",       \
863                     (long)cxstack_ix,                                   \
864                     action,                                             \
865                     PL_block_type[CxTYPE(&cxstack[cxstack_ix])],        \
866                     (long)PL_scopestack_ix,                             \
867                     (long)(cxstack[cxstack_ix].blk_oldscopesp),         \
868                     __FILE__, __LINE__));
869
870 /* Enter a block. */
871 #define PUSHBLOCK(cx,t,sp) CXINC, cx = &cxstack[cxstack_ix],            \
872         cx->cx_type             = t,                                    \
873         cx->blk_oldsp           = sp - PL_stack_base,                   \
874         cx->blk_oldcop          = PL_curcop,                            \
875         cx->blk_oldmarksp       = PL_markstack_ptr - PL_markstack,      \
876         cx->blk_oldscopesp      = PL_scopestack_ix,                     \
877         cx->blk_oldpm           = PL_curpm,                             \
878         cx->blk_gimme           = (U8)gimme;                            \
879         DEBUG_CX("PUSH");
880
881 /* Exit a block (RETURN and LAST). */
882 #define POPBLOCK(cx,pm)                                                 \
883         DEBUG_CX("POP");                                                \
884         cx = &cxstack[cxstack_ix--],                                    \
885         newsp            = PL_stack_base + cx->blk_oldsp,               \
886         PL_curcop        = cx->blk_oldcop,                              \
887         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
888         PL_scopestack_ix = cx->blk_oldscopesp,                          \
889         pm               = cx->blk_oldpm,                               \
890         gimme            = cx->blk_gimme;
891
892 /* Continue a block elsewhere (NEXT and REDO). */
893 #define TOPBLOCK(cx)                                                    \
894         DEBUG_CX("TOP");                                                \
895         cx  = &cxstack[cxstack_ix],                                     \
896         PL_stack_sp      = PL_stack_base + cx->blk_oldsp,               \
897         PL_markstack_ptr = PL_markstack + cx->blk_oldmarksp,            \
898         PL_scopestack_ix = cx->blk_oldscopesp,                          \
899         PL_curpm         = cx->blk_oldpm;
900
901 /* substitution context */
902 struct subst {
903     U8          sbu_type;       /* what kind of context this is */
904     U8          sbu_rflags;
905     U16         sbu_rxtainted;  /* matches struct block */
906     I32         sbu_iters;
907     I32         sbu_maxiters;
908     I32         sbu_oldsave;
909     char *      sbu_orig;
910     SV *        sbu_dstr;
911     SV *        sbu_targ;
912     char *      sbu_s;
913     char *      sbu_m;
914     char *      sbu_strend;
915     void *      sbu_rxres;
916     REGEXP *    sbu_rx;
917 };
918 #define sb_iters        cx_u.cx_subst.sbu_iters
919 #define sb_maxiters     cx_u.cx_subst.sbu_maxiters
920 #define sb_rflags       cx_u.cx_subst.sbu_rflags
921 #define sb_oldsave      cx_u.cx_subst.sbu_oldsave
922 #define sb_rxtainted    cx_u.cx_subst.sbu_rxtainted
923 #define sb_orig         cx_u.cx_subst.sbu_orig
924 #define sb_dstr         cx_u.cx_subst.sbu_dstr
925 #define sb_targ         cx_u.cx_subst.sbu_targ
926 #define sb_s            cx_u.cx_subst.sbu_s
927 #define sb_m            cx_u.cx_subst.sbu_m
928 #define sb_strend       cx_u.cx_subst.sbu_strend
929 #define sb_rxres        cx_u.cx_subst.sbu_rxres
930 #define sb_rx           cx_u.cx_subst.sbu_rx
931
932 #ifdef PERL_CORE
933 #  define PUSHSUBST(cx) CXINC, cx = &cxstack[cxstack_ix],               \
934         cx->sb_iters            = iters,                                \
935         cx->sb_maxiters         = maxiters,                             \
936         cx->sb_rflags           = r_flags,                              \
937         cx->sb_oldsave          = oldsave,                              \
938         cx->sb_rxtainted        = rxtainted,                            \
939         cx->sb_orig             = orig,                                 \
940         cx->sb_dstr             = dstr,                                 \
941         cx->sb_targ             = targ,                                 \
942         cx->sb_s                = s,                                    \
943         cx->sb_m                = m,                                    \
944         cx->sb_strend           = strend,                               \
945         cx->sb_rxres            = NULL,                                 \
946         cx->sb_rx               = rx,                                   \
947         cx->cx_type             = CXt_SUBST | (once ? CXp_ONCE : 0);    \
948         rxres_save(&cx->sb_rxres, rx);                                  \
949         (void)ReREFCNT_inc(rx)
950
951 #  define POPSUBST(cx) cx = &cxstack[cxstack_ix--];                     \
952         rxres_free(&cx->sb_rxres);                                      \
953         ReREFCNT_dec(cx->sb_rx)
954 #endif
955
956 #define CxONCE(cx)              ((cx)->cx_type & CXp_ONCE)
957
958 struct context {
959     union {
960         struct block    cx_blk;
961         struct subst    cx_subst;
962     } cx_u;
963 };
964 #define cx_type cx_u.cx_subst.sbu_type
965
966 /* If you re-order these, there is also an array of uppercase names in perl.h
967    and a static array of context names in pp_ctl.c  */
968 #define CXTYPEMASK      0xf
969 #define CXt_NULL        0
970 #define CXt_WHEN        1
971 #define CXt_BLOCK       2
972 /* When micro-optimising :-) keep GIVEN next to the LOOPs, as these 5 share a
973    jump table in pp_ctl.c
974    The first 4 don't have a 'case' in at least one switch statement in pp_ctl.c
975 */
976 #define CXt_GIVEN       3
977 /* This is first so that CXt_LOOP_FOR|CXt_LOOP_LAZYIV is CXt_LOOP_LAZYIV */
978 #define CXt_LOOP_FOR    4
979 #define CXt_LOOP_PLAIN  5
980 #define CXt_LOOP_LAZYSV 6
981 #define CXt_LOOP_LAZYIV 7
982 #define CXt_SUB         8
983 #define CXt_FORMAT      9
984 #define CXt_EVAL       10
985 #define CXt_SUBST      11
986 /* SUBST doesn't feature in all switch statements.  */
987
988 /* private flags for CXt_SUB and CXt_NULL
989    However, this is checked in many places which do not check the type, so
990    this bit needs to be kept clear for most everything else. For reasons I
991    haven't investigated, it can coexist with CXp_FOR_DEF */
992 #define CXp_MULTICALL   0x10    /* part of a multicall (so don't
993                                    tear down context on exit). */ 
994
995 /* private flags for CXt_SUB and CXt_FORMAT */
996 #define CXp_HASARGS     0x20
997
998 /* private flags for CXt_EVAL */
999 #define CXp_REAL        0x20    /* truly eval'', not a lookalike */
1000 #define CXp_TRYBLOCK    0x40    /* eval{}, not eval'' or similar */
1001
1002 /* private flags for CXt_LOOP */
1003 #define CXp_FOR_DEF     0x10    /* foreach using $_ */
1004 #define CxPADLOOP(c)    ((c)->blk_loop.my_op->op_targ)
1005
1006 /* private flags for CXt_SUBST */
1007 #define CXp_ONCE        0x10    /* What was sbu_once in struct subst */
1008
1009 #define CxTYPE(c)       ((c)->cx_type & CXTYPEMASK)
1010 #define CxTYPE_is_LOOP(c)       (((c)->cx_type & 0xC) == 0x4)
1011 #define CxMULTICALL(c)  (((c)->cx_type & CXp_MULTICALL)                 \
1012                          == CXp_MULTICALL)
1013 #define CxREALEVAL(c)   (((c)->cx_type & (CXTYPEMASK|CXp_REAL))         \
1014                          == (CXt_EVAL|CXp_REAL))
1015 #define CxTRYBLOCK(c)   (((c)->cx_type & (CXTYPEMASK|CXp_TRYBLOCK))     \
1016                          == (CXt_EVAL|CXp_TRYBLOCK))
1017 #define CxFOREACH(c)    (CxTYPE_is_LOOP(c) && CxTYPE(c) != CXt_LOOP_PLAIN)
1018 #define CxFOREACHDEF(c) ((CxTYPE_is_LOOP(c) && CxTYPE(c) != CXt_LOOP_PLAIN) \
1019                          && ((c)->cx_type & CXp_FOR_DEF))
1020
1021 #define CXINC (cxstack_ix < cxstack_max ? ++cxstack_ix : (cxstack_ix = cxinc()))
1022
1023 /* 
1024 =head1 "Gimme" Values
1025 */
1026
1027 /*
1028 =for apidoc AmU||G_SCALAR
1029 Used to indicate scalar context.  See C<GIMME_V>, C<GIMME>, and
1030 L<perlcall>.
1031
1032 =for apidoc AmU||G_ARRAY
1033 Used to indicate list context.  See C<GIMME_V>, C<GIMME> and
1034 L<perlcall>.
1035
1036 =for apidoc AmU||G_VOID
1037 Used to indicate void context.  See C<GIMME_V> and L<perlcall>.
1038
1039 =for apidoc AmU||G_DISCARD
1040 Indicates that arguments returned from a callback should be discarded.  See
1041 L<perlcall>.
1042
1043 =for apidoc AmU||G_EVAL
1044
1045 Used to force a Perl C<eval> wrapper around a callback.  See
1046 L<perlcall>.
1047
1048 =for apidoc AmU||G_NOARGS
1049
1050 Indicates that no arguments are being sent to a callback.  See
1051 L<perlcall>.
1052
1053 =cut
1054 */
1055
1056 #define G_SCALAR        2
1057 #define G_ARRAY         3
1058 #define G_VOID          1
1059 #define G_WANT          3
1060
1061 /* extra flags for Perl_call_* routines */
1062 #define G_DISCARD       4       /* Call FREETMPS.
1063                                    Don't change this without consulting the
1064                                    hash actions codes defined in hv.h */
1065 #define G_EVAL          8       /* Assume eval {} around subroutine call. */
1066 #define G_NOARGS       16       /* Don't construct a @_ array. */
1067 #define G_KEEPERR      32       /* Warn for errors, don't overwrite $@ */
1068 #define G_NODEBUG      64       /* Disable debugging at toplevel.  */
1069 #define G_METHOD      128       /* Calling method. */
1070 #define G_FAKINGEVAL  256       /* Faking an eval context for call_sv or
1071                                    fold_constants. */
1072 #define G_UNDEF_FILL  512       /* Fill the stack with &PL_sv_undef
1073                                    A special case for UNSHIFT in
1074                                    Perl_magic_methcall().  */
1075 #define G_WRITING_TO_STDERR 1024 /* Perl_write_to_stderr() is calling
1076                                     Perl_magic_methcall().  */
1077
1078 /* flag bits for PL_in_eval */
1079 #define EVAL_NULL       0       /* not in an eval */
1080 #define EVAL_INEVAL     1       /* some enclosing scope is an eval */
1081 #define EVAL_WARNONLY   2       /* used by yywarn() when calling yyerror() */
1082 #define EVAL_KEEPERR    4       /* set by Perl_call_sv if G_KEEPERR */
1083 #define EVAL_INREQUIRE  8       /* The code is being required. */
1084
1085 /* Support for switching (stack and block) contexts.
1086  * This ensures magic doesn't invalidate local stack and cx pointers.
1087  */
1088
1089 #define PERLSI_UNKNOWN          -1
1090 #define PERLSI_UNDEF            0
1091 #define PERLSI_MAIN             1
1092 #define PERLSI_MAGIC            2
1093 #define PERLSI_SORT             3
1094 #define PERLSI_SIGNAL           4
1095 #define PERLSI_OVERLOAD         5
1096 #define PERLSI_DESTROY          6
1097 #define PERLSI_WARNHOOK         7
1098 #define PERLSI_DIEHOOK          8
1099 #define PERLSI_REQUIRE          9
1100
1101 struct stackinfo {
1102     AV *                si_stack;       /* stack for current runlevel */
1103     PERL_CONTEXT *      si_cxstack;     /* context stack for runlevel */
1104     struct stackinfo *  si_prev;
1105     struct stackinfo *  si_next;
1106     I32                 si_cxix;        /* current context index */
1107     I32                 si_cxmax;       /* maximum allocated index */
1108     I32                 si_type;        /* type of runlevel */
1109     I32                 si_markoff;     /* offset where markstack begins for us.
1110                                          * currently used only with DEBUGGING,
1111                                          * but not #ifdef-ed for bincompat */
1112 };
1113
1114 typedef struct stackinfo PERL_SI;
1115
1116 #define cxstack         (PL_curstackinfo->si_cxstack)
1117 #define cxstack_ix      (PL_curstackinfo->si_cxix)
1118 #define cxstack_max     (PL_curstackinfo->si_cxmax)
1119
1120 #ifdef DEBUGGING
1121 #  define       SET_MARK_OFFSET \
1122     PL_curstackinfo->si_markoff = PL_markstack_ptr - PL_markstack
1123 #else
1124 #  define       SET_MARK_OFFSET NOOP
1125 #endif
1126
1127 #define PUSHSTACKi(type) \
1128     STMT_START {                                                        \
1129         PERL_SI *next = PL_curstackinfo->si_next;                       \
1130         DEBUG_l({                                                       \
1131             int i = 0; PERL_SI *p = PL_curstackinfo;                    \
1132             while (p) { i++; p = p->si_prev; }                          \
1133             Perl_deb(aTHX_ "push STACKINFO %d at %s:%d\n",              \
1134                          i, __FILE__, __LINE__);})                      \
1135         if (!next) {                                                    \
1136             next = new_stackinfo(32, 2048/sizeof(PERL_CONTEXT) - 1);    \
1137             next->si_prev = PL_curstackinfo;                            \
1138             PL_curstackinfo->si_next = next;                            \
1139         }                                                               \
1140         next->si_type = type;                                           \
1141         next->si_cxix = -1;                                             \
1142         AvFILLp(next->si_stack) = 0;                                    \
1143         SWITCHSTACK(PL_curstack,next->si_stack);                        \
1144         PL_curstackinfo = next;                                         \
1145         SET_MARK_OFFSET;                                                \
1146     } STMT_END
1147
1148 #define PUSHSTACK PUSHSTACKi(PERLSI_UNKNOWN)
1149
1150 /* POPSTACK works with PL_stack_sp, so it may need to be bracketed by
1151  * PUTBACK/SPAGAIN to flush/refresh any local SP that may be active */
1152 #define POPSTACK \
1153     STMT_START {                                                        \
1154         dSP;                                                            \
1155         PERL_SI * const prev = PL_curstackinfo->si_prev;                \
1156         DEBUG_l({                                                       \
1157             int i = -1; PERL_SI *p = PL_curstackinfo;                   \
1158             while (p) { i++; p = p->si_prev; }                          \
1159             Perl_deb(aTHX_ "pop  STACKINFO %d at %s:%d\n",              \
1160                          i, __FILE__, __LINE__);})                      \
1161         if (!prev) {                                                    \
1162             PerlIO_printf(Perl_error_log, "panic: POPSTACK\n");         \
1163             my_exit(1);                                                 \
1164         }                                                               \
1165         SWITCHSTACK(PL_curstack,prev->si_stack);                        \
1166         /* don't free prev here, free them all at the END{} */          \
1167         PL_curstackinfo = prev;                                         \
1168     } STMT_END
1169
1170 #define POPSTACK_TO(s) \
1171     STMT_START {                                                        \
1172         while (PL_curstack != s) {                                      \
1173             dounwind(-1);                                               \
1174             POPSTACK;                                                   \
1175         }                                                               \
1176     } STMT_END
1177
1178 #define IN_PERL_COMPILETIME     (PL_curcop == &PL_compiling)
1179 #define IN_PERL_RUNTIME         (PL_curcop != &PL_compiling)
1180
1181 /*
1182 =head1 Multicall Functions
1183
1184 =for apidoc Ams||dMULTICALL
1185 Declare local variables for a multicall. See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1186
1187 =for apidoc Ams||PUSH_MULTICALL
1188 Opening bracket for a lightweight callback.
1189 See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1190
1191 =for apidoc Ams||MULTICALL
1192 Make a lightweight callback. See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1193
1194 =for apidoc Ams||POP_MULTICALL
1195 Closing bracket for a lightweight callback.
1196 See L<perlcall/LIGHTWEIGHT CALLBACKS>.
1197
1198 =cut
1199 */
1200
1201 #define dMULTICALL \
1202     SV **newsp;                 /* set by POPBLOCK */                   \
1203     PERL_CONTEXT *cx;                                                   \
1204     CV *multicall_cv;                                                   \
1205     OP *multicall_cop;                                                  \
1206     bool multicall_oldcatch;                                            \
1207     U8 hasargs = 0              /* used by PUSHSUB */
1208
1209 #define PUSH_MULTICALL(the_cv) \
1210     STMT_START {                                                        \
1211         CV * const _nOnclAshIngNamE_ = the_cv;                          \
1212         CV * const cv = _nOnclAshIngNamE_;                              \
1213         AV * const padlist = CvPADLIST(cv);                             \
1214         ENTER;                                                          \
1215         multicall_oldcatch = CATCH_GET;                                 \
1216         SAVETMPS; SAVEVPTR(PL_op);                                      \
1217         CATCH_SET(TRUE);                                                \
1218         PUSHSTACKi(PERLSI_SORT);                                        \
1219         PUSHBLOCK(cx, CXt_SUB|CXp_MULTICALL, PL_stack_sp);              \
1220         PUSHSUB(cx);                                                    \
1221         if (++CvDEPTH(cv) >= 2) {                                       \
1222             PERL_STACK_OVERFLOW_CHECK();                                \
1223             Perl_pad_push(aTHX_ padlist, CvDEPTH(cv));                  \
1224         }                                                               \
1225         SAVECOMPPAD();                                                  \
1226         PAD_SET_CUR_NOSAVE(padlist, CvDEPTH(cv));                       \
1227         multicall_cv = cv;                                              \
1228         multicall_cop = CvSTART(cv);                                    \
1229     } STMT_END
1230
1231 #define MULTICALL \
1232     STMT_START {                                                        \
1233         PL_op = multicall_cop;                                          \
1234         CALLRUNOPS(aTHX);                                               \
1235     } STMT_END
1236
1237 #define POP_MULTICALL \
1238     STMT_START {                                                        \
1239         if (! --CvDEPTH(multicall_cv))                                  \
1240             LEAVESUB(multicall_cv);                                     \
1241         POPBLOCK(cx,PL_curpm);                                          \
1242         POPSTACK;                                                       \
1243         CATCH_SET(multicall_oldcatch);                                  \
1244         LEAVE;                                                          \
1245         SPAGAIN;                                                        \
1246     } STMT_END
1247
1248 /*
1249  * Local variables:
1250  * c-indentation-style: bsd
1251  * c-basic-offset: 4
1252  * indent-tabs-mode: t
1253  * End:
1254  *
1255  * ex: set ts=8 sts=4 sw=4 noet:
1256  */