Commit | Line | Data |
---|---|---|
eb1102fc NIS |
1 | /* perlvars.h |
2 | * | |
663f364b | 3 | * Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, |
54ca4ee7 | 4 | * by Larry Wall and others |
eb1102fc NIS |
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 | */ | |
10 | ||
88e1f1a2 JV |
11 | /* |
12 | =head1 Global Variables | |
e8570548 | 13 | These variables are global to an entire process. They are shared between |
5a4fed09 KW |
14 | all interpreters and all threads in a process. Any variables not documented |
15 | here may be changed or removed without notice, so don't use them! | |
16 | If you feel you really do need to use an unlisted variable, first send email to | |
17 | L<perl5-porters@perl.org|mailto:perl5-porters@perl.org>. It may be that | |
18 | someone there will point out a way to accomplish what you need without using an | |
19 | internal variable. But if not, you should get a go-ahead to document and then | |
20 | use the variable. | |
e8570548 Z |
21 | |
22 | =cut | |
88e1f1a2 | 23 | */ |
49f531da | 24 | |
d7cb65f2 | 25 | /* Don't forget to re-run regen/embed.pl to propagate changes! */ |
cb68f92d GS |
26 | |
27 | /* This file describes the "global" variables used by perl | |
28 | * This used to be in perl.h directly but we want to abstract out into | |
29 | * distinct files which are per-thread, per-interpreter or really global, | |
30 | * and how they're initialized. | |
31 | * | |
32 | * The 'G' prefix is only needed for vars that need appropriate #defines | |
22c35a8c | 33 | * generated in embed*.h. Such symbols are also used to generate |
14dd3ad8 | 34 | * the appropriate export list for win32. */ |
cb68f92d | 35 | |
49f531da | 36 | /* global state */ |
eeb6b841 | 37 | #if defined(USE_ITHREADS) |
115ff745 | 38 | PERLVAR(G, op_mutex, perl_mutex) /* Mutex for op refcounting */ |
eeb6b841 | 39 | #endif |
5c64bffd | 40 | PERLVARI(G, curinterp, PerlInterpreter *, NULL) |
1604cfb0 MS |
41 | /* currently running interpreter |
42 | * (initial parent interpreter under | |
43 | * useithreads) */ | |
3db8f154 | 44 | #if defined(USE_ITHREADS) |
115ff745 | 45 | PERLVAR(G, thr_key, perl_key) /* key to retrieve per-thread struct */ |
ba869deb | 46 | #endif |
a0ed51b3 | 47 | |
43165c05 | 48 | /* XXX does anyone even use this? */ |
115ff745 | 49 | PERLVARI(G, do_undump, bool, FALSE) /* -u or dump seen? */ |
b363f7ed | 50 | |
eeb6b841 | 51 | #if defined(FAKE_PERSISTENT_SIGNAL_HANDLERS)||defined(FAKE_DEFAULT_SIGNAL_HANDLERS) |
115ff745 | 52 | PERLVARI(G, sig_handlers_initted, int, 0) |
534825c4 | 53 | #endif |
eeb6b841 | 54 | #ifdef FAKE_PERSISTENT_SIGNAL_HANDLERS |
115ff745 | 55 | PERLVARA(G, sig_ignoring, SIG_SIZE, int) |
1604cfb0 | 56 | /* which signals we are ignoring */ |
eeb6b841 NC |
57 | #endif |
58 | #ifdef FAKE_DEFAULT_SIGNAL_HANDLERS | |
115ff745 | 59 | PERLVARA(G, sig_defaulting, SIG_SIZE, int) |
d90a703e | 60 | #endif |
5c728af0 | 61 | |
eeb6b841 NC |
62 | /* XXX signals are process-wide anyway, so we |
63 | * ignore the implications of this for threading */ | |
64 | #ifndef HAS_SIGACTION | |
115ff745 | 65 | PERLVARI(G, sig_trapped, int, 0) |
428eed4a | 66 | #endif |
af419de7 | 67 | |
2f42fcb0 | 68 | #ifndef PERL_MICRO |
b35112e7 CS |
69 | /* If Perl has to ignore SIGPFE, this is its saved state. |
70 | * See perl.h macros PERL_FPU_INIT and PERL_FPU_{PRE,POST}_EXEC. */ | |
115ff745 | 71 | PERLVAR(G, sigfpe_saved, Sighandler_t) |
dc37125b DM |
72 | |
73 | /* these ptrs to functions are to avoid linkage problems; see | |
74 | * perl-5.8.0-2193-g5c1546dc48 | |
75 | */ | |
76 | PERLVARI(G, csighandlerp, Sighandler_t, Perl_csighandler) | |
77 | PERLVARI(G, csighandler1p, Sighandler1_t, Perl_csighandler1) | |
78 | PERLVARI(G, csighandler3p, Sighandler3_t, Perl_csighandler3) | |
2f42fcb0 | 79 | #endif |
5c1546dc | 80 | |
eeb6b841 NC |
81 | /* This is constant on most architectures, a global on OS/2 */ |
82 | #ifdef OS2 | |
115ff745 | 83 | PERLVARI(G, sh_path, char *, SH_PATH) /* full path of shell */ |
50acdf95 | 84 | #endif |
27da23d5 JH |
85 | |
86 | #ifdef USE_PERLIO | |
eeb6b841 NC |
87 | |
88 | # if defined(USE_ITHREADS) | |
115ff745 | 89 | PERLVAR(G, perlio_mutex, perl_mutex) /* Mutex for perlio fd refcounts */ |
eeb6b841 NC |
90 | # endif |
91 | ||
115ff745 NC |
92 | PERLVARI(G, perlio_fd_refcnt, int *, 0) /* Pointer to array of fd refcounts. */ |
93 | PERLVARI(G, perlio_fd_refcnt_size, int, 0) /* Size of the array */ | |
94 | PERLVARI(G, perlio_debug_fd, int, 0) /* the fd to write perlio debug into, 0 means not set yet */ | |
27da23d5 JH |
95 | #endif |
96 | ||
97 | #ifdef HAS_MMAP | |
115ff745 | 98 | PERLVARI(G, mmap_page_size, IV, 0) |
27da23d5 JH |
99 | #endif |
100 | ||
eeb6b841 | 101 | #if defined(USE_ITHREADS) |
115ff745 | 102 | PERLVAR(G, hints_mutex, perl_mutex) /* Mutex for refcounted he refcounting */ |
57d4826a | 103 | PERLVAR(G, env_mutex, perl_RnW1_mutex_t) /* Mutex for accessing ENV */ |
407c2aaa | 104 | PERLVAR(G, locale_mutex, perl_mutex) /* Mutex related to locale handling */ |
5acc3fa5 | 105 | #endif |
6ebbc862 | 106 | |
39e69e77 | 107 | #ifdef USE_POSIX_2008_LOCALE |
67f006ee | 108 | PERLVARI(G, C_locale_obj, locale_t, NULL) |
27da23d5 JH |
109 | #endif |
110 | ||
0c5ea019 | 111 | PERLVARI(G, watch_pvx, char *, NULL) |
27da23d5 | 112 | |
e8570548 | 113 | /* |
78342678 | 114 | =for apidoc AmnU|Perl_check_t *|PL_check |
e8570548 Z |
115 | |
116 | Array, indexed by opcode, of functions that will be called for the "check" | |
117 | phase of optree building during compilation of Perl code. For most (but | |
118 | not all) types of op, once the op has been initially built and populated | |
119 | with child ops it will be filtered through the check function referenced | |
120 | by the appropriate element of this array. The new op is passed in as the | |
121 | sole argument to the check function, and the check function returns the | |
122 | completed op. The check function may (as the name suggests) check the op | |
123 | for validity and signal errors. It may also initialise or modify parts of | |
124 | the ops, or perform more radical surgery such as adding or removing child | |
125 | ops, or even throw the op away and return a different op in its place. | |
126 | ||
127 | This array of function pointers is a convenient place to hook into the | |
128 | compilation process. An XS module can put its own custom check function | |
129 | in place of any of the standard ones, to influence the compilation of a | |
130 | particular type of op. However, a custom check function must never fully | |
131 | replace a standard check function (or even a custom check function from | |
132 | another module). A module modifying checking must instead B<wrap> the | |
133 | preexisting check function. A custom check function must be selective | |
134 | about when to apply its custom behaviour. In the usual case where | |
135 | it decides not to do anything special with an op, it must chain the | |
136 | preexisting op function. Check functions are thus linked in a chain, | |
137 | with the core's base checker at the end. | |
138 | ||
139 | For thread safety, modules should not write directly to this array. | |
140 | Instead, use the function L</wrap_op_checker>. | |
141 | ||
5e18b295 FG |
142 | =for apidoc Amn|enum perl_phase|PL_phase |
143 | ||
144 | A value that indicates the current Perl interpreter's phase. Possible values | |
145 | include C<PERL_PHASE_CONSTRUCT>, C<PERL_PHASE_START>, C<PERL_PHASE_CHECK>, | |
146 | C<PERL_PHASE_INIT>, C<PERL_PHASE_RUN>, C<PERL_PHASE_END>, and | |
147 | C<PERL_PHASE_DESTRUCT>. | |
148 | ||
149 | For example, the following determines whether the interpreter is in | |
150 | global destruction: | |
151 | ||
152 | if (PL_phase == PERL_PHASE_DESTRUCT) { | |
153 | // we are in global destruction | |
154 | } | |
155 | ||
156 | C<PL_phase> was introduced in Perl 5.14; in prior perls you can use | |
157 | C<PL_dirty> (boolean) to determine whether the interpreter is in global | |
158 | destruction. (Use of C<PL_dirty> is discouraged since 5.14.) | |
159 | ||
e8570548 Z |
160 | =cut |
161 | */ | |
162 | ||
163 | #if defined(USE_ITHREADS) | |
164 | PERLVAR(G, check_mutex, perl_mutex) /* Mutex for PL_check */ | |
165 | #endif | |
27da23d5 | 166 | |
f16dd614 | 167 | /* allocate a unique index to every module that calls MY_CXT_INIT */ |
27da23d5 | 168 | |
6e512bc2 | 169 | #ifdef MULTIPLICITY |
97aff369 | 170 | # ifdef USE_ITHREADS |
115ff745 | 171 | PERLVAR(G, my_ctx_mutex, perl_mutex) |
644641ff | 172 | PERLVARI(G, veto_switch_non_tTHX_context, int, FALSE) |
97aff369 | 173 | # endif |
115ff745 | 174 | PERLVARI(G, my_cxt_index, int, 0) |
f16dd614 | 175 | #endif |
71ad1b0c | 176 | |
c301d606 DM |
177 | /* this is currently set without MUTEX protection, so keep it a type which |
178 | * can be set atomically (ie not a bit field) */ | |
115ff745 | 179 | PERLVARI(G, veto_cleanup, int, FALSE) /* exit without cleanup */ |
c301d606 | 180 | |
88e1f1a2 | 181 | /* |
78342678 | 182 | =for apidoc AmnUx|Perl_keyword_plugin_t|PL_keyword_plugin |
88e1f1a2 JV |
183 | |
184 | Function pointer, pointing at a function used to handle extended keywords. | |
185 | The function should be declared as | |
186 | ||
1604cfb0 MS |
187 | int keyword_plugin_function(pTHX_ |
188 | char *keyword_ptr, STRLEN keyword_len, | |
189 | OP **op_ptr) | |
88e1f1a2 JV |
190 | |
191 | The function is called from the tokeniser, whenever a possible keyword | |
192 | is seen. C<keyword_ptr> points at the word in the parser's input | |
193 | buffer, and C<keyword_len> gives its length; it is not null-terminated. | |
194 | The function is expected to examine the word, and possibly other state | |
195 | such as L<%^H|perlvar/%^H>, to decide whether it wants to handle it | |
196 | as an extended keyword. If it does not, the function should return | |
197 | C<KEYWORD_PLUGIN_DECLINE>, and the normal parser process will continue. | |
198 | ||
199 | If the function wants to handle the keyword, it first must | |
200 | parse anything following the keyword that is part of the syntax | |
f0e67a1d | 201 | introduced by the keyword. See L</Lexer interface> for details. |
88e1f1a2 JV |
202 | |
203 | When a keyword is being handled, the plugin function must build | |
204 | a tree of C<OP> structures, representing the code that was parsed. | |
205 | The root of the tree must be stored in C<*op_ptr>. The function then | |
364f83bf | 206 | returns a constant indicating the syntactic role of the construct that |
88e1f1a2 JV |
207 | it has parsed: C<KEYWORD_PLUGIN_STMT> if it is a complete statement, or |
208 | C<KEYWORD_PLUGIN_EXPR> if it is an expression. Note that a statement | |
209 | construct cannot be used inside an expression (except via C<do BLOCK> | |
210 | and similar), and an expression is not a complete statement (it requires | |
211 | at least a terminating semicolon). | |
212 | ||
213 | When a keyword is handled, the plugin function may also have | |
214 | (compile-time) side effects. It may modify C<%^H>, define functions, and | |
215 | so on. Typically, if side effects are the main purpose of a handler, | |
216 | it does not wish to generate any ops to be included in the normal | |
217 | compilation. In this case it is still required to supply an op tree, | |
218 | but it suffices to generate a single null op. | |
219 | ||
220 | That's how the C<*PL_keyword_plugin> function needs to behave overall. | |
221 | Conventionally, however, one does not completely replace the existing | |
222 | handler function. Instead, take a copy of C<PL_keyword_plugin> before | |
223 | assigning your own function pointer to it. Your handler function should | |
224 | look for keywords that it is interested in and handle those. Where it | |
225 | is not interested, it should call the saved plugin function, passing on | |
226 | the arguments it received. Thus C<PL_keyword_plugin> actually points | |
227 | at a chain of handler functions, all of which have an opportunity to | |
228 | handle keywords, and only the last function in the chain (built into | |
229 | the Perl core) will normally return C<KEYWORD_PLUGIN_DECLINE>. | |
230 | ||
1e5c5f69 LM |
231 | For thread safety, modules should not set this variable directly. |
232 | Instead, use the function L</wrap_keyword_plugin>. | |
233 | ||
88e1f1a2 JV |
234 | =cut |
235 | */ | |
236 | ||
1e5c5f69 | 237 | #if defined(USE_ITHREADS) |
cd7d7848 | 238 | PERLVAR(G, keyword_plugin_mutex, perl_mutex) /* Mutex for PL_keyword_plugin and PL_infix_plugin */ |
1e5c5f69 | 239 | #endif |
115ff745 | 240 | PERLVARI(G, keyword_plugin, Perl_keyword_plugin_t, Perl_keyword_plugin_standard) |
eeb6b841 | 241 | |
51fd43e9 PE |
242 | /* |
243 | =for apidoc AmnUx|Perl_infix_plugin_t|PL_infix_plugin | |
244 | ||
245 | B<NOTE:> This API exists entirely for the purpose of making the CPAN module | |
246 | C<XS::Parse::Infix> work. It is not expected that additional modules will make | |
247 | use of it; rather, that they should use C<XS::Parse::Infix> to provide parsing | |
248 | of new infix operators. | |
249 | ||
250 | Function pointer, pointing at a function used to handle extended infix | |
251 | operators. The function should be declared as | |
252 | ||
253 | int infix_plugin_function(pTHX_ | |
254 | char *opname, STRLEN oplen, | |
255 | struct Perl_custom_infix **infix_ptr) | |
256 | ||
257 | The function is called from the tokenizer whenever a possible infix operator | |
258 | is seen. C<opname> points to the operator name in the parser's input buffer, | |
259 | and C<oplen> gives the I<maximum> number of bytes of it that should be | |
260 | consumed; it is not null-terminated. The function is expected to examine the | |
261 | operator name and possibly other state such as L<%^H|perlvar/%^H>, to | |
262 | determine whether it wants to handle the operator name. | |
263 | ||
264 | As compared to the single stage of C<PL_keyword_plugin>, parsing of additional | |
265 | infix operators occurs in three separate stages. This is because of the more | |
266 | complex interactions it has with the parser, to ensure that operator | |
267 | precedence rules work correctly. These stages are co-ordinated by the use of | |
268 | an additional information structure. | |
269 | ||
270 | If the function wants to handle the infix operator, it must set the variable | |
271 | pointed to by C<infix_ptr> to the address of a structure that provides this | |
272 | additional information about the subsequent parsing stages. If it does not, | |
273 | it should make a call to the next function in the chain. | |
274 | ||
275 | This structure has the following definition: | |
276 | ||
277 | struct Perl_custom_infix { | |
278 | enum Perl_custom_infix_precedence prec; | |
279 | void (*parse)(pTHX_ SV **opdata, | |
280 | struct Perl_custom_infix *); | |
281 | OP *(*build_op)(pTHX_ SV **opdata, OP *lhs, OP *rhs, | |
282 | struct Perl_custom_infix *); | |
283 | }; | |
284 | ||
285 | The function must then return an integer giving the number of bytes consumed | |
286 | by the name of this operator. In the case of an operator whose name is | |
287 | composed of identifier characters, this must be equal to C<oplen>. In the case | |
288 | of an operator named by non-identifier characters, this is permitted to be | |
289 | shorter than C<oplen>, and any additional characters after it will not be | |
290 | claimed by the infix operator but instead will be consumed by the tokenizer | |
291 | and parser as normal. | |
292 | ||
293 | If the optional C<parse> function is provided, it is called immediately by the | |
294 | parser to let the operator's definition consume any additional syntax from the | |
295 | source code. This should I<not> be used for normal operand parsing, but it may | |
296 | be useful when implementing things like parametric operators or meta-operators | |
297 | that consume more syntax themselves. This function may use the variable | |
298 | pointed to by C<opdata> to provide an SV containing additional data to be | |
299 | passed into the C<build_op> function later on. | |
300 | ||
301 | The information structure gives the operator precedence level in the C<prec> | |
302 | field. This is used to tell the parser how much of the surrounding syntax | |
303 | before and after should be considered as operands to the operator. | |
304 | ||
305 | The tokenizer and parser will then continue to operate as normal until enough | |
306 | additional input has been parsed to form both the left- and right-hand side | |
307 | operands to the operator, according to the precedence level. At this point the | |
308 | C<build_op> function is called, being passed the left- and right-hand operands | |
309 | as optree fragments. It is expected to combine them into the resulting optree | |
310 | fragment, which it should return. | |
311 | ||
312 | After the C<build_op> function has returned, if the variable pointed to by | |
313 | C<opdata> was set to a non-C<NULL> value, it will then be destroyed by calling | |
314 | C<SvREFCNT_dec()>. | |
315 | ||
316 | For thread safety, modules should not set this variable directly. | |
317 | Instead, use the function L</wrap_infix_plugin>. | |
318 | ||
319 | However, that all said, the introductory note above still applies. This | |
320 | variable is provided in core perl only for the benefit of the | |
321 | C<XS::Parse::Infix> module. That module acts as a central registry for infix | |
322 | operators, automatically handling things like deparse support and | |
323 | discovery/reflection, and these abilities only work because it knows all the | |
324 | registered operators. Other modules should not use this interpreter variable | |
325 | directly to implement them because then those central features would no longer | |
326 | work properly. | |
327 | ||
328 | Furthermore, it is likely that this (experimental) API will be replaced in a | |
329 | future Perl version by a more complete API that fully implements the central | |
330 | registry and other semantics currently provided by C<XS::Parse::Infix>, once | |
331 | the module has had sufficient experimental testing time. This current | |
332 | mechanism exists only as an interim measure to get to that stage. | |
333 | ||
334 | =cut | |
335 | */ | |
336 | ||
cd7d7848 PE |
337 | PERLVARI(G, infix_plugin, Perl_infix_plugin_t, Perl_infix_plugin_standard) |
338 | ||
5c64bffd | 339 | PERLVARI(G, op_sequence, HV *, NULL) /* dump.c */ |
115ff745 | 340 | PERLVARI(G, op_seq, UV, 0) /* dump.c */ |
eeb6b841 NC |
341 | |
342 | #ifdef USE_ITHREADS | |
115ff745 | 343 | PERLVAR(G, dollarzero_mutex, perl_mutex) /* Modifying $0 */ |
eeb6b841 NC |
344 | #endif |
345 | ||
346 | /* Restricted hashes placeholder value. | |
5c64bffd NC |
347 | In theory, the contents are never used, only the address. |
348 | In practice, &PL_sv_placeholder is returned by some APIs, and the calling | |
349 | code is checking SvOK(). */ | |
350 | ||
115ff745 | 351 | PERLVAR(G, sv_placeholder, SV) |
eeb6b841 NC |
352 | |
353 | #if defined(MYMALLOC) && defined(USE_ITHREADS) | |
115ff745 | 354 | PERLVAR(G, malloc_mutex, perl_mutex) /* Mutex for malloc */ |
eeb6b841 | 355 | #endif |
7dc86639 YO |
356 | |
357 | PERLVARI(G, hash_seed_set, bool, FALSE) /* perl.c */ | |
58411bc7 | 358 | PERLVARA(G, hash_seed_w, PERL_HASH_SEED_WORDS, PVT__PERL_HASH_WORD_TYPE) /* perl.c and hv.h */ |
9d5e3f1a | 359 | #if defined(PERL_HASH_STATE_BYTES) |
58411bc7 | 360 | PERLVARA(G, hash_state_w, PERL_HASH_STATE_WORDS, PVT__PERL_HASH_WORD_TYPE) /* perl.c and hv.h */ |
9d5e3f1a YO |
361 | #endif |
362 | #if defined(PERL_USE_SINGLE_CHAR_HASH_CACHE) | |
c5cd648d YO |
363 | #define PERL_SINGLE_CHAR_HASH_CACHE_ELEMS ((1+256) * sizeof(U32)) |
364 | PERLVARA(G, hash_chars, PERL_SINGLE_CHAR_HASH_CACHE_ELEMS, unsigned char) /* perl.c and hv.h */ | |
9d5e3f1a | 365 | #endif |
483efd0a CB |
366 | |
367 | /* The path separator can vary depending on whether we're running under DCL or | |
368 | * a Unix shell. | |
369 | */ | |
370 | #ifdef __VMS | |
371 | PERLVAR(G, perllib_sep, char) | |
372 | #endif | |
744ebf52 | 373 | |
dd52e3cc KW |
374 | /* Definitions of user-defined \p{} properties, as the subs that define them |
375 | * are only called once */ | |
376 | PERLVARI(G, user_def_props, HV *, NULL) | |
377 | ||
8310e7fa | 378 | #if defined(USE_ITHREADS) |
dd52e3cc KW |
379 | PERLVAR(G, user_def_props_aTHX, PerlInterpreter *) /* aTHX that user_def_props |
380 | was defined in */ | |
381 | PERLVAR(G, user_prop_mutex, perl_mutex) /* Mutex for manipulating | |
382 | PL_user_defined_properties */ | |
8310e7fa KW |
383 | #endif |
384 | ||
a3815e44 | 385 | /* these record the best way to perform certain IO operations while |
999d65ed DM |
386 | * atomically setting FD_CLOEXEC. On the first call, a probe is done |
387 | * and the result recorded for use by subsequent calls. | |
388 | * In theory these variables aren't thread-safe, but the worst that can | |
389 | * happen is that two treads will both do an initial probe | |
390 | */ | |
391 | PERLVARI(G, strategy_dup, int, 0) /* doio.c */ | |
392 | PERLVARI(G, strategy_dup2, int, 0) /* doio.c */ | |
393 | PERLVARI(G, strategy_open, int, 0) /* doio.c */ | |
394 | PERLVARI(G, strategy_open3, int, 0) /* doio.c */ | |
395 | PERLVARI(G, strategy_mkstemp, int, 0) /* doio.c */ | |
396 | PERLVARI(G, strategy_socket, int, 0) /* doio.c */ | |
397 | PERLVARI(G, strategy_accept, int, 0) /* doio.c */ | |
398 | PERLVARI(G, strategy_pipe, int, 0) /* doio.c */ | |
399 | PERLVARI(G, strategy_socketpair, int, 0) /* doio.c */ | |
b95d2334 TK |
400 | |
401 | PERLVARI(G, my_environ, char **, NULL) | |
66673af5 | 402 | PERLVARI(G, origenviron, char **, NULL) |