This is a live mirror of the Perl 5 development currently hosted at https://github.com/perl/perl5
Remove old MSVC++ (pre-VC12) support from Windows Makefiles
[perl5.git] / perlvars.h
CommitLineData
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 13These variables are global to an entire process. They are shared between
5a4fed09
KW
14all interpreters and all threads in a process. Any variables not documented
15here may be changed or removed without notice, so don't use them!
16If you feel you really do need to use an unlisted variable, first send email to
17L<perl5-porters@perl.org|mailto:perl5-porters@perl.org>. It may be that
18someone there will point out a way to accomplish what you need without using an
19internal variable. But if not, you should get a go-ahead to document and then
20use 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 38PERLVAR(G, op_mutex, perl_mutex) /* Mutex for op refcounting */
eeb6b841 39#endif
5c64bffd 40PERLVARI(G, curinterp, PerlInterpreter *, NULL)
1604cfb0
MS
41 /* currently running interpreter
42 * (initial parent interpreter under
43 * useithreads) */
3db8f154 44#if defined(USE_ITHREADS)
115ff745 45PERLVAR(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 49PERLVARI(G, do_undump, bool, FALSE) /* -u or dump seen? */
b363f7ed 50
eeb6b841 51#ifndef PERL_USE_SAFE_PUTENV
115ff745 52PERLVARI(G, use_safe_putenv, bool, TRUE)
b363f7ed 53#endif
534825c4 54
eeb6b841 55#if defined(FAKE_PERSISTENT_SIGNAL_HANDLERS)||defined(FAKE_DEFAULT_SIGNAL_HANDLERS)
115ff745 56PERLVARI(G, sig_handlers_initted, int, 0)
534825c4 57#endif
eeb6b841 58#ifdef FAKE_PERSISTENT_SIGNAL_HANDLERS
115ff745 59PERLVARA(G, sig_ignoring, SIG_SIZE, int)
1604cfb0 60 /* which signals we are ignoring */
eeb6b841
NC
61#endif
62#ifdef FAKE_DEFAULT_SIGNAL_HANDLERS
115ff745 63PERLVARA(G, sig_defaulting, SIG_SIZE, int)
d90a703e 64#endif
5c728af0 65
eeb6b841
NC
66/* XXX signals are process-wide anyway, so we
67 * ignore the implications of this for threading */
68#ifndef HAS_SIGACTION
115ff745 69PERLVARI(G, sig_trapped, int, 0)
428eed4a 70#endif
af419de7 71
2f42fcb0 72#ifndef PERL_MICRO
b35112e7
CS
73/* If Perl has to ignore SIGPFE, this is its saved state.
74 * See perl.h macros PERL_FPU_INIT and PERL_FPU_{PRE,POST}_EXEC. */
115ff745 75PERLVAR(G, sigfpe_saved, Sighandler_t)
dc37125b
DM
76
77/* these ptrs to functions are to avoid linkage problems; see
78 * perl-5.8.0-2193-g5c1546dc48
79 */
80PERLVARI(G, csighandlerp, Sighandler_t, Perl_csighandler)
81PERLVARI(G, csighandler1p, Sighandler1_t, Perl_csighandler1)
82PERLVARI(G, csighandler3p, Sighandler3_t, Perl_csighandler3)
2f42fcb0 83#endif
5c1546dc 84
eeb6b841
NC
85/* This is constant on most architectures, a global on OS/2 */
86#ifdef OS2
115ff745 87PERLVARI(G, sh_path, char *, SH_PATH) /* full path of shell */
50acdf95 88#endif
27da23d5
JH
89
90#ifdef USE_PERLIO
eeb6b841
NC
91
92# if defined(USE_ITHREADS)
115ff745 93PERLVAR(G, perlio_mutex, perl_mutex) /* Mutex for perlio fd refcounts */
eeb6b841
NC
94# endif
95
115ff745
NC
96PERLVARI(G, perlio_fd_refcnt, int *, 0) /* Pointer to array of fd refcounts. */
97PERLVARI(G, perlio_fd_refcnt_size, int, 0) /* Size of the array */
98PERLVARI(G, perlio_debug_fd, int, 0) /* the fd to write perlio debug into, 0 means not set yet */
27da23d5
JH
99#endif
100
101#ifdef HAS_MMAP
115ff745 102PERLVARI(G, mmap_page_size, IV, 0)
27da23d5
JH
103#endif
104
eeb6b841 105#if defined(USE_ITHREADS)
115ff745 106PERLVAR(G, hints_mutex, perl_mutex) /* Mutex for refcounted he refcounting */
57d4826a 107PERLVAR(G, env_mutex, perl_RnW1_mutex_t) /* Mutex for accessing ENV */
407c2aaa 108PERLVAR(G, locale_mutex, perl_mutex) /* Mutex related to locale handling */
69c5e0db 109# ifndef USE_THREAD_SAFE_LOCALE
49d7d366 110PERLVAR(G, lc_numeric_mutex, perl_mutex) /* Mutex for switching LC_NUMERIC */
423a80b7 111# endif
5acc3fa5 112#endif
6ebbc862 113
39e69e77 114#ifdef USE_POSIX_2008_LOCALE
5acc3fa5 115PERLVAR(G, C_locale_obj, locale_t)
27da23d5
JH
116#endif
117
0c5ea019 118PERLVARI(G, watch_pvx, char *, NULL)
27da23d5 119
e8570548 120/*
78342678 121=for apidoc AmnU|Perl_check_t *|PL_check
e8570548
Z
122
123Array, indexed by opcode, of functions that will be called for the "check"
124phase of optree building during compilation of Perl code. For most (but
125not all) types of op, once the op has been initially built and populated
126with child ops it will be filtered through the check function referenced
127by the appropriate element of this array. The new op is passed in as the
128sole argument to the check function, and the check function returns the
129completed op. The check function may (as the name suggests) check the op
130for validity and signal errors. It may also initialise or modify parts of
131the ops, or perform more radical surgery such as adding or removing child
132ops, or even throw the op away and return a different op in its place.
133
134This array of function pointers is a convenient place to hook into the
135compilation process. An XS module can put its own custom check function
136in place of any of the standard ones, to influence the compilation of a
137particular type of op. However, a custom check function must never fully
138replace a standard check function (or even a custom check function from
139another module). A module modifying checking must instead B<wrap> the
140preexisting check function. A custom check function must be selective
141about when to apply its custom behaviour. In the usual case where
142it decides not to do anything special with an op, it must chain the
143preexisting op function. Check functions are thus linked in a chain,
144with the core's base checker at the end.
145
146For thread safety, modules should not write directly to this array.
147Instead, use the function L</wrap_op_checker>.
148
5e18b295
FG
149=for apidoc Amn|enum perl_phase|PL_phase
150
151A value that indicates the current Perl interpreter's phase. Possible values
152include C<PERL_PHASE_CONSTRUCT>, C<PERL_PHASE_START>, C<PERL_PHASE_CHECK>,
153C<PERL_PHASE_INIT>, C<PERL_PHASE_RUN>, C<PERL_PHASE_END>, and
154C<PERL_PHASE_DESTRUCT>.
155
156For example, the following determines whether the interpreter is in
157global destruction:
158
159 if (PL_phase == PERL_PHASE_DESTRUCT) {
160 // we are in global destruction
161 }
162
163C<PL_phase> was introduced in Perl 5.14; in prior perls you can use
164C<PL_dirty> (boolean) to determine whether the interpreter is in global
165destruction. (Use of C<PL_dirty> is discouraged since 5.14.)
166
e8570548
Z
167=cut
168*/
169
170#if defined(USE_ITHREADS)
171PERLVAR(G, check_mutex, perl_mutex) /* Mutex for PL_check */
172#endif
27da23d5 173
f16dd614 174/* allocate a unique index to every module that calls MY_CXT_INIT */
27da23d5 175
6e512bc2 176#ifdef MULTIPLICITY
97aff369 177# ifdef USE_ITHREADS
115ff745 178PERLVAR(G, my_ctx_mutex, perl_mutex)
97aff369 179# endif
115ff745 180PERLVARI(G, my_cxt_index, int, 0)
f16dd614 181#endif
71ad1b0c 182
c301d606
DM
183/* this is currently set without MUTEX protection, so keep it a type which
184 * can be set atomically (ie not a bit field) */
115ff745 185PERLVARI(G, veto_cleanup, int, FALSE) /* exit without cleanup */
c301d606 186
88e1f1a2 187/*
78342678 188=for apidoc AmnUx|Perl_keyword_plugin_t|PL_keyword_plugin
88e1f1a2
JV
189
190Function pointer, pointing at a function used to handle extended keywords.
191The function should be declared as
192
1604cfb0
MS
193 int keyword_plugin_function(pTHX_
194 char *keyword_ptr, STRLEN keyword_len,
195 OP **op_ptr)
88e1f1a2
JV
196
197The function is called from the tokeniser, whenever a possible keyword
198is seen. C<keyword_ptr> points at the word in the parser's input
199buffer, and C<keyword_len> gives its length; it is not null-terminated.
200The function is expected to examine the word, and possibly other state
201such as L<%^H|perlvar/%^H>, to decide whether it wants to handle it
202as an extended keyword. If it does not, the function should return
203C<KEYWORD_PLUGIN_DECLINE>, and the normal parser process will continue.
204
205If the function wants to handle the keyword, it first must
206parse anything following the keyword that is part of the syntax
f0e67a1d 207introduced by the keyword. See L</Lexer interface> for details.
88e1f1a2
JV
208
209When a keyword is being handled, the plugin function must build
210a tree of C<OP> structures, representing the code that was parsed.
211The root of the tree must be stored in C<*op_ptr>. The function then
364f83bf 212returns a constant indicating the syntactic role of the construct that
88e1f1a2
JV
213it has parsed: C<KEYWORD_PLUGIN_STMT> if it is a complete statement, or
214C<KEYWORD_PLUGIN_EXPR> if it is an expression. Note that a statement
215construct cannot be used inside an expression (except via C<do BLOCK>
216and similar), and an expression is not a complete statement (it requires
217at least a terminating semicolon).
218
219When a keyword is handled, the plugin function may also have
220(compile-time) side effects. It may modify C<%^H>, define functions, and
221so on. Typically, if side effects are the main purpose of a handler,
222it does not wish to generate any ops to be included in the normal
223compilation. In this case it is still required to supply an op tree,
224but it suffices to generate a single null op.
225
226That's how the C<*PL_keyword_plugin> function needs to behave overall.
227Conventionally, however, one does not completely replace the existing
228handler function. Instead, take a copy of C<PL_keyword_plugin> before
229assigning your own function pointer to it. Your handler function should
230look for keywords that it is interested in and handle those. Where it
231is not interested, it should call the saved plugin function, passing on
232the arguments it received. Thus C<PL_keyword_plugin> actually points
233at a chain of handler functions, all of which have an opportunity to
234handle keywords, and only the last function in the chain (built into
235the Perl core) will normally return C<KEYWORD_PLUGIN_DECLINE>.
236
1e5c5f69
LM
237For thread safety, modules should not set this variable directly.
238Instead, use the function L</wrap_keyword_plugin>.
239
88e1f1a2
JV
240=cut
241*/
242
1e5c5f69
LM
243#if defined(USE_ITHREADS)
244PERLVAR(G, keyword_plugin_mutex, perl_mutex) /* Mutex for PL_keyword_plugin */
245#endif
115ff745 246PERLVARI(G, keyword_plugin, Perl_keyword_plugin_t, Perl_keyword_plugin_standard)
eeb6b841 247
5c64bffd 248PERLVARI(G, op_sequence, HV *, NULL) /* dump.c */
115ff745 249PERLVARI(G, op_seq, UV, 0) /* dump.c */
eeb6b841
NC
250
251#ifdef USE_ITHREADS
115ff745 252PERLVAR(G, dollarzero_mutex, perl_mutex) /* Modifying $0 */
eeb6b841
NC
253#endif
254
255/* Restricted hashes placeholder value.
5c64bffd
NC
256 In theory, the contents are never used, only the address.
257 In practice, &PL_sv_placeholder is returned by some APIs, and the calling
258 code is checking SvOK(). */
259
115ff745 260PERLVAR(G, sv_placeholder, SV)
eeb6b841
NC
261
262#if defined(MYMALLOC) && defined(USE_ITHREADS)
115ff745 263PERLVAR(G, malloc_mutex, perl_mutex) /* Mutex for malloc */
eeb6b841 264#endif
7dc86639
YO
265
266PERLVARI(G, hash_seed_set, bool, FALSE) /* perl.c */
f43079cb 267PERLVARA(G, hash_seed_w, PERL_HASH_SEED_WORDS, __PERL_HASH_WORD_TYPE) /* perl.c and hv.h */
9d5e3f1a 268#if defined(PERL_HASH_STATE_BYTES)
f43079cb 269PERLVARA(G, hash_state_w, PERL_HASH_STATE_WORDS, __PERL_HASH_WORD_TYPE) /* perl.c and hv.h */
9d5e3f1a
YO
270#endif
271#if defined(PERL_USE_SINGLE_CHAR_HASH_CACHE)
272PERLVARA(G, hash_chars, (1+256) * sizeof(U32), unsigned char) /* perl.c and hv.h */
273#endif
483efd0a
CB
274
275/* The path separator can vary depending on whether we're running under DCL or
276 * a Unix shell.
277 */
278#ifdef __VMS
279PERLVAR(G, perllib_sep, char)
280#endif
744ebf52 281
dd52e3cc
KW
282/* Definitions of user-defined \p{} properties, as the subs that define them
283 * are only called once */
284PERLVARI(G, user_def_props, HV *, NULL)
285
8310e7fa 286#if defined(USE_ITHREADS)
dd52e3cc
KW
287PERLVAR(G, user_def_props_aTHX, PerlInterpreter *) /* aTHX that user_def_props
288 was defined in */
289PERLVAR(G, user_prop_mutex, perl_mutex) /* Mutex for manipulating
290 PL_user_defined_properties */
8310e7fa
KW
291#endif
292
a3815e44 293/* these record the best way to perform certain IO operations while
999d65ed
DM
294 * atomically setting FD_CLOEXEC. On the first call, a probe is done
295 * and the result recorded for use by subsequent calls.
296 * In theory these variables aren't thread-safe, but the worst that can
297 * happen is that two treads will both do an initial probe
298 */
299PERLVARI(G, strategy_dup, int, 0) /* doio.c */
300PERLVARI(G, strategy_dup2, int, 0) /* doio.c */
301PERLVARI(G, strategy_open, int, 0) /* doio.c */
302PERLVARI(G, strategy_open3, int, 0) /* doio.c */
303PERLVARI(G, strategy_mkstemp, int, 0) /* doio.c */
304PERLVARI(G, strategy_socket, int, 0) /* doio.c */
305PERLVARI(G, strategy_accept, int, 0) /* doio.c */
306PERLVARI(G, strategy_pipe, int, 0) /* doio.c */
307PERLVARI(G, strategy_socketpair, int, 0) /* doio.c */