3 * Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
4 * by Larry Wall and others
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.
12 =head1 Global Variables
15 /* Don't forget to re-run regen/embed.pl to propagate changes! */
17 /* This file describes the "global" variables used by perl
18 * This used to be in perl.h directly but we want to abstract out into
19 * distinct files which are per-thread, per-interpreter or really global,
20 * and how they're initialized.
22 * The 'G' prefix is only needed for vars that need appropriate #defines
23 * generated in embed*.h. Such symbols are also used to generate
24 * the appropriate export list for win32. */
27 PERLVAR(Gcurinterp, PerlInterpreter *)
28 /* currently running interpreter
29 * (initial parent interpreter under
31 #if defined(USE_ITHREADS)
32 PERLVAR(Gthr_key, perl_key) /* key to retrieve per-thread struct */
35 /* constants (these are not literals to facilitate pointer comparisons)
36 * (PERLVARISC really does create variables, despite its looks) */
39 PERLVARISC(Ghexdigit, "0123456789abcdef0123456789ABCDEF")
40 PERLVARISC(Gpatleave, "\\.^$@dDwWsSbB+*?|()-nrtfeaxc0123456789[{]}")
42 /* XXX does anyone even use this? */
43 PERLVARI(Gdo_undump, bool, FALSE) /* -u or dump seen? */
45 #if defined(MYMALLOC) && defined(USE_ITHREADS)
46 PERLVAR(Gmalloc_mutex, perl_mutex) /* Mutex for malloc */
49 #if defined(USE_ITHREADS)
50 PERLVAR(Gop_mutex, perl_mutex) /* Mutex for op refcounting */
54 PERLVAR(Gdollarzero_mutex, perl_mutex) /* Modifying $0 */
58 /* This is constant on most architectures, a global on OS/2 */
62 # define PERL___C const
64 PERLVARI(Gsh_path, PERL___C char *, SH_PATH) /* full path of shell */
68 /* If Perl has to ignore SIGPFE, this is its saved state.
69 * See perl.h macros PERL_FPU_INIT and PERL_FPU_{PRE,POST}_EXEC. */
70 PERLVAR(Gsigfpe_saved, Sighandler_t)
73 /* Restricted hashes placeholder value.
74 * The contents are never used, only the address. */
75 PERLVAR(Gsv_placeholder, SV)
78 PERLVARI(Gcsighandlerp, Sighandler_t, Perl_csighandler) /* Pointer to C-level sighandler */
81 #ifndef PERL_USE_SAFE_PUTENV
82 PERLVARI(Guse_safe_putenv, int, 1)
86 PERLVARI(Gperlio_fd_refcnt, int*, 0) /* Pointer to array of fd refcounts. */
87 PERLVARI(Gperlio_fd_refcnt_size, int, 0) /* Size of the array */
88 PERLVARI(Gperlio_debug_fd, int, 0) /* the fd to write perlio debug into, 0 means not set yet */
92 PERLVARI(Gmmap_page_size, IV, 0)
95 #if defined(FAKE_PERSISTENT_SIGNAL_HANDLERS)||defined(FAKE_DEFAULT_SIGNAL_HANDLERS)
96 PERLVARI(Gsig_handlers_initted, int, 0)
98 #ifdef FAKE_PERSISTENT_SIGNAL_HANDLERS
99 PERLVARA(Gsig_ignoring, SIG_SIZE, int) /* which signals we are ignoring */
101 #ifdef FAKE_DEFAULT_SIGNAL_HANDLERS
102 PERLVARA(Gsig_defaulting, SIG_SIZE, int)
105 /* XXX signals are process-wide anyway, so we
106 * ignore the implications of this for threading */
107 #ifndef HAS_SIGACTION
108 PERLVARI(Gsig_trapped, int, 0)
112 PERLVAR(Gwatch_pvx, char*)
115 #ifdef PERL_GLOBAL_STRUCT
116 PERLVAR(Gppaddr, Perl_ppaddr_t*) /* or opcode.h */
117 PERLVAR(Gcheck, Perl_check_t *) /* or opcode.h */
118 PERLVARA(Gfold_locale, 256, unsigned char) /* or perl.h */
121 #ifdef PERL_NEED_APPCTX
122 PERLVAR(Gappctx, void*) /* the application context */
125 PERLVAR(Gop_sequence, HV*) /* dump.c */
126 PERLVARI(Gop_seq, UV, 0) /* dump.c */
128 #if defined(HAS_TIMES) && defined(PERL_NEED_TIMESBASE)
129 PERLVAR(Gtimesbase, struct tms)
132 /* allocate a unique index to every module that calls MY_CXT_INIT */
134 #ifdef PERL_IMPLICIT_CONTEXT
136 PERLVAR(Gmy_ctx_mutex, perl_mutex)
138 PERLVARI(Gmy_cxt_index, int, 0)
141 #if defined(USE_ITHREADS)
142 PERLVAR(Ghints_mutex, perl_mutex) /* Mutex for refcounted he refcounting */
145 #if defined(USE_ITHREADS)
146 PERLVAR(Gperlio_mutex, perl_mutex) /* Mutex for perlio fd refcounts */
149 /* this is currently set without MUTEX protection, so keep it a type which
150 * can be set atomically (ie not a bit field) */
151 PERLVARI(Gveto_cleanup, int, FALSE) /* exit without cleanup */
153 /* dummy variables that hold pointers to both runops functions, thus forcing
154 * them *both* to get linked in (useful for Peek.xs, debugging etc) */
156 PERLVARI(Grunops_std, runops_proc_t, Perl_runops_standard)
157 PERLVARI(Grunops_dbg, runops_proc_t, Perl_runops_debug)
160 /* These are baked at compile time into any shared perl library.
161 In future 5.10.x releases this will allow us in main() to sanity test the
162 library we're linking against. */
164 PERLVARI(Grevision, U8, PERL_REVISION)
165 PERLVARI(Gversion, U8, PERL_VERSION)
166 PERLVARI(Gsubversion, U8, PERL_SUBVERSION)
168 #if defined(MULTIPLICITY)
169 # define PERL_INTERPRETER_SIZE_UPTO_MEMBER(member) \
170 STRUCT_OFFSET(struct interpreter, member) + \
171 sizeof(((struct interpreter*)0)->member)
173 /* These might be useful. */
174 PERLVARI(Ginterp_size, U16, sizeof(struct interpreter))
175 #if defined(PERL_GLOBAL_STRUCT)
176 PERLVARI(Gglobal_struct_size, U16, sizeof(struct perl_vars))
179 /* This will be useful for subsequent releases, because this has to be the
180 same in your libperl as in main(), else you have a mismatch and must abort.
182 PERLVARI(Ginterp_size_5_10_0, U16,
183 PERL_INTERPRETER_SIZE_UPTO_MEMBER(PERL_LAST_5_10_0_INTERP_MEMBER))
187 =for apidoc AmUx|Perl_keyword_plugin_t|PL_keyword_plugin
189 Function pointer, pointing at a function used to handle extended keywords.
190 The function should be declared as
192 int keyword_plugin_function(pTHX_
193 char *keyword_ptr, STRLEN keyword_len,
196 The function is called from the tokeniser, whenever a possible keyword
197 is seen. C<keyword_ptr> points at the word in the parser's input
198 buffer, and C<keyword_len> gives its length; it is not null-terminated.
199 The function is expected to examine the word, and possibly other state
200 such as L<%^H|perlvar/%^H>, to decide whether it wants to handle it
201 as an extended keyword. If it does not, the function should return
202 C<KEYWORD_PLUGIN_DECLINE>, and the normal parser process will continue.
204 If the function wants to handle the keyword, it first must
205 parse anything following the keyword that is part of the syntax
206 introduced by the keyword. See L</Lexer interface> for details.
208 When a keyword is being handled, the plugin function must build
209 a tree of C<OP> structures, representing the code that was parsed.
210 The root of the tree must be stored in C<*op_ptr>. The function then
211 returns a constant indicating the syntactic role of the construct that
212 it has parsed: C<KEYWORD_PLUGIN_STMT> if it is a complete statement, or
213 C<KEYWORD_PLUGIN_EXPR> if it is an expression. Note that a statement
214 construct cannot be used inside an expression (except via C<do BLOCK>
215 and similar), and an expression is not a complete statement (it requires
216 at least a terminating semicolon).
218 When a keyword is handled, the plugin function may also have
219 (compile-time) side effects. It may modify C<%^H>, define functions, and
220 so on. Typically, if side effects are the main purpose of a handler,
221 it does not wish to generate any ops to be included in the normal
222 compilation. In this case it is still required to supply an op tree,
223 but it suffices to generate a single null op.
225 That's how the C<*PL_keyword_plugin> function needs to behave overall.
226 Conventionally, however, one does not completely replace the existing
227 handler function. Instead, take a copy of C<PL_keyword_plugin> before
228 assigning your own function pointer to it. Your handler function should
229 look for keywords that it is interested in and handle those. Where it
230 is not interested, it should call the saved plugin function, passing on
231 the arguments it received. Thus C<PL_keyword_plugin> actually points
232 at a chain of handler functions, all of which have an opportunity to
233 handle keywords, and only the last function in the chain (built into
234 the Perl core) will normally return C<KEYWORD_PLUGIN_DECLINE>.
239 PERLVARI(Gkeyword_plugin, Perl_keyword_plugin_t, Perl_keyword_plugin_standard)