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 */
119 PERLVARA(Gcharclass, 256, U32)
122 #ifdef PERL_NEED_APPCTX
123 PERLVAR(Gappctx, void*) /* the application context */
126 PERLVAR(Gop_sequence, HV*) /* dump.c */
127 PERLVARI(Gop_seq, UV, 0) /* dump.c */
129 #if defined(HAS_TIMES) && defined(PERL_NEED_TIMESBASE)
130 PERLVAR(Gtimesbase, struct tms)
133 /* allocate a unique index to every module that calls MY_CXT_INIT */
135 #ifdef PERL_IMPLICIT_CONTEXT
137 PERLVAR(Gmy_ctx_mutex, perl_mutex)
139 PERLVARI(Gmy_cxt_index, int, 0)
142 #if defined(USE_ITHREADS)
143 PERLVAR(Ghints_mutex, perl_mutex) /* Mutex for refcounted he refcounting */
146 #if defined(USE_ITHREADS)
147 PERLVAR(Gperlio_mutex, perl_mutex) /* Mutex for perlio fd refcounts */
150 /* this is currently set without MUTEX protection, so keep it a type which
151 * can be set atomically (ie not a bit field) */
152 PERLVARI(Gveto_cleanup, int, FALSE) /* exit without cleanup */
154 /* dummy variables that hold pointers to both runops functions, thus forcing
155 * them *both* to get linked in (useful for Peek.xs, debugging etc) */
157 PERLVARI(Grunops_std, runops_proc_t, Perl_runops_standard)
158 PERLVARI(Grunops_dbg, runops_proc_t, Perl_runops_debug)
161 /* These are baked at compile time into any shared perl library.
162 In future 5.10.x releases this will allow us in main() to sanity test the
163 library we're linking against. */
165 PERLVARI(Grevision, U8, PERL_REVISION)
166 PERLVARI(Gversion, U8, PERL_VERSION)
167 PERLVARI(Gsubversion, U8, PERL_SUBVERSION)
169 #if defined(MULTIPLICITY)
170 # define PERL_INTERPRETER_SIZE_UPTO_MEMBER(member) \
171 STRUCT_OFFSET(struct interpreter, member) + \
172 sizeof(((struct interpreter*)0)->member)
174 /* These might be useful. */
175 PERLVARI(Ginterp_size, U16, sizeof(struct interpreter))
176 #if defined(PERL_GLOBAL_STRUCT)
177 PERLVARI(Gglobal_struct_size, U16, sizeof(struct perl_vars))
180 /* This will be useful for subsequent releases, because this has to be the
181 same in your libperl as in main(), else you have a mismatch and must abort.
183 PERLVARI(Ginterp_size_5_10_0, U16,
184 PERL_INTERPRETER_SIZE_UPTO_MEMBER(PERL_LAST_5_10_0_INTERP_MEMBER))
188 =for apidoc AmUx|Perl_keyword_plugin_t|PL_keyword_plugin
190 Function pointer, pointing at a function used to handle extended keywords.
191 The function should be declared as
193 int keyword_plugin_function(pTHX_
194 char *keyword_ptr, STRLEN keyword_len,
197 The function is called from the tokeniser, whenever a possible keyword
198 is seen. C<keyword_ptr> points at the word in the parser's input
199 buffer, and C<keyword_len> gives its length; it is not null-terminated.
200 The function is expected to examine the word, and possibly other state
201 such as L<%^H|perlvar/%^H>, to decide whether it wants to handle it
202 as an extended keyword. If it does not, the function should return
203 C<KEYWORD_PLUGIN_DECLINE>, and the normal parser process will continue.
205 If the function wants to handle the keyword, it first must
206 parse anything following the keyword that is part of the syntax
207 introduced by the keyword. See L</Lexer interface> for details.
209 When a keyword is being handled, the plugin function must build
210 a tree of C<OP> structures, representing the code that was parsed.
211 The root of the tree must be stored in C<*op_ptr>. The function then
212 returns a constant indicating the syntactic role of the construct that
213 it has parsed: C<KEYWORD_PLUGIN_STMT> if it is a complete statement, or
214 C<KEYWORD_PLUGIN_EXPR> if it is an expression. Note that a statement
215 construct cannot be used inside an expression (except via C<do BLOCK>
216 and similar), and an expression is not a complete statement (it requires
217 at least a terminating semicolon).
219 When a keyword is handled, the plugin function may also have
220 (compile-time) side effects. It may modify C<%^H>, define functions, and
221 so on. Typically, if side effects are the main purpose of a handler,
222 it does not wish to generate any ops to be included in the normal
223 compilation. In this case it is still required to supply an op tree,
224 but it suffices to generate a single null op.
226 That's how the C<*PL_keyword_plugin> function needs to behave overall.
227 Conventionally, however, one does not completely replace the existing
228 handler function. Instead, take a copy of C<PL_keyword_plugin> before
229 assigning your own function pointer to it. Your handler function should
230 look for keywords that it is interested in and handle those. Where it
231 is not interested, it should call the saved plugin function, passing on
232 the arguments it received. Thus C<PL_keyword_plugin> actually points
233 at a chain of handler functions, all of which have an opportunity to
234 handle keywords, and only the last function in the chain (built into
235 the Perl core) will normally return C<KEYWORD_PLUGIN_DECLINE>.
240 PERLVARI(Gkeyword_plugin, Perl_keyword_plugin_t, Perl_keyword_plugin_standard)