xref: /openbsd/gnu/usr.bin/perl/regen/mg_vtable.pl (revision cecf84d4)
1#!/usr/bin/perl -w
2#
3# Regenerate (overwriting only if changed):
4#
5#    mg_names.c
6#    mg_raw.h
7#    mg_vtable.h
8#    pod/perlguts.pod
9#
10# from information stored in this file.  pod/perlguts.pod is not completely
11# regenerated.  Only the magic table is replaced; the other parts remain
12# untouched.
13#
14# Accepts the standard regen_lib -q and -v args.
15#
16# This script is normally invoked from regen.pl.
17
18use strict;
19require 5.004;
20
21BEGIN {
22    # Get function prototypes
23    require 'regen/regen_lib.pl';
24}
25
26my %mg =
27    (
28     sv => { char => '\0', vtable => 'sv', readonly_acceptable => 1,
29	     desc => 'Special scalar variable' },
30     # overload, or type "A" magic, used to be here.  Hence overloaded is
31     # often called AMAGIC internally, even though it does not use "A"
32     # magic any more.
33     overload_table => { char => 'c', vtable => 'ovrld',
34			 desc => 'Holds overload table (AMT) on stash' },
35     bm => { char => 'B', vtable => 'regexp', value_magic => 1,
36	     readonly_acceptable => 1,
37	     desc => 'Boyer-Moore (fast string search)' },
38     regdata => { char => 'D', vtable => 'regdata',
39		  desc => "Regex match position data\n(\@+ and \@- vars)" },
40     regdatum => { char => 'd', vtable => 'regdatum',
41		   desc => 'Regex match position data element' },
42     env => { char => 'E', vtable => 'env', desc => '%ENV hash' },
43     envelem => { char => 'e', vtable => 'envelem',
44		  desc => '%ENV hash element' },
45     fm => { char => 'f', vtable => 'regexp', value_magic => 1,
46	     readonly_acceptable => 1, desc => "Formline ('compiled' format)" },
47     regex_global => { char => 'g', vtable => 'mglob', value_magic => 1,
48		       readonly_acceptable => 1, desc => 'm//g target' },
49     hints => { char => 'H', vtable => 'hints', desc => '%^H hash' },
50     hintselem => { char => 'h', vtable => 'hintselem',
51		    desc => '%^H hash element' },
52     isa => { char => 'I', vtable => 'isa', desc => '@ISA array' },
53     isaelem => { char => 'i', vtable => 'isaelem',
54		  desc => '@ISA array element' },
55     nkeys => { char => 'k', vtable => 'nkeys', value_magic => 1,
56		desc => 'scalar(keys()) lvalue' },
57     dbfile => { char => 'L',
58		 desc => 'Debugger %_<filename' },
59     dbline => { char => 'l', vtable => 'dbline',
60		 desc => 'Debugger %_<filename element' },
61     shared => { char => 'N', desc => 'Shared between threads',
62		 unknown_to_sv_magic => 1 },
63     shared_scalar => { char => 'n', desc => 'Shared between threads',
64			unknown_to_sv_magic => 1 },
65     collxfrm => { char => 'o', vtable => 'collxfrm', value_magic => 1,
66		   desc => 'Locale transformation' },
67     tied => { char => 'P', vtable => 'pack',
68	       value_magic => 1, # treat as value, so 'local @tied' isn't tied
69	       desc => 'Tied array or hash' },
70     tiedelem => { char => 'p', vtable => 'packelem',
71		   desc => 'Tied array or hash element' },
72     tiedscalar => { char => 'q', vtable => 'packelem',
73		     desc => 'Tied scalar or handle' },
74     qr => { char => 'r', vtable => 'regexp', value_magic => 1,
75	     readonly_acceptable => 1, desc => 'precompiled qr// regex' },
76     sig => { char => 'S', desc => '%SIG hash' },
77     sigelem => { char => 's', vtable => 'sigelem',
78		  desc => '%SIG hash element' },
79     taint => { char => 't', vtable => 'taint', value_magic => 1,
80		desc => 'Taintedness' },
81     uvar => { char => 'U', vtable => 'uvar',
82	       desc => 'Available for use by extensions' },
83     uvar_elem => { char => 'u', desc => 'Reserved for use by extensions',
84		    unknown_to_sv_magic => 1 },
85     vec => { char => 'v', vtable => 'vec', value_magic => 1,
86	      desc => 'vec() lvalue' },
87     vstring => { char => 'V', value_magic => 1,
88		  desc => 'SV was vstring literal' },
89     utf8 => { char => 'w', vtable => 'utf8', value_magic => 1,
90	       desc => 'Cached UTF-8 information' },
91     substr => { char => 'x', vtable => 'substr',  value_magic => 1,
92		 desc => 'substr() lvalue' },
93     defelem => { char => 'y', vtable => 'defelem', value_magic => 1,
94		  desc => "Shadow \"foreach\" iterator variable /\nsmart parameter vivification" },
95     arylen => { char => '#', vtable => 'arylen', value_magic => 1,
96		 desc => 'Array length ($#ary)' },
97     proto => { char => '&', desc => 'my sub prototype CV' },
98     pos => { char => '.', vtable => 'pos', value_magic => 1,
99	      desc => 'pos() lvalue' },
100     backref => { char => '<', vtable => 'backref', value_magic => 1,
101		  readonly_acceptable => 1, desc => 'for weak ref data' },
102     symtab => { char => ':', value_magic => 1,
103		 desc => 'extra data for symbol tables' },
104     rhash => { char => '%', value_magic => 1,
105		desc => 'extra data for restricted hashes' },
106     arylen_p => { char => '@', value_magic => 1,
107		   desc => 'to move arylen out of XPVAV' },
108     ext => { char => '~', desc => 'Available for use by extensions' },
109     checkcall => { char => ']', value_magic => 1, vtable => 'checkcall',
110		    desc => 'inlining/mutation of call to this CV'},
111);
112
113# These have a subtly different "namespace" from the magic types.
114my %sig =
115    (
116     'sv' => {get => 'get', set => 'set'},
117     'env' => {set => 'set_all_env', clear => 'clear_all_env'},
118     'envelem' => {set => 'setenv', clear => 'clearenv'},
119     'sigelem' => {get => 'getsig', set => 'setsig', clear => 'clearsig',
120		   cond => '#ifndef PERL_MICRO'},
121     'pack' => {len => 'sizepack', clear => 'wipepack'},
122     'packelem' => {get => 'getpack', set => 'setpack', clear => 'clearpack'},
123     'dbline' => {set => 'setdbline'},
124     'isa' => {set => 'setisa', clear => 'clearisa'},
125     'isaelem' => {set => 'setisa'},
126     'arylen' => {get => 'getarylen', set => 'setarylen', const => 1},
127     'arylen_p' => {clear => 'cleararylen_p', free => 'freearylen_p'},
128     'mglob' => {set => 'setmglob'},
129     'nkeys' => {get => 'getnkeys', set => 'setnkeys'},
130     'taint' => {get => 'gettaint', set => 'settaint'},
131     'substr' => {get => 'getsubstr', set => 'setsubstr'},
132     'vec' => {get => 'getvec', set => 'setvec'},
133     'pos' => {get => 'getpos', set => 'setpos'},
134     'uvar' => {get => 'getuvar', set => 'setuvar'},
135     'defelem' => {get => 'getdefelem', set => 'setdefelem'},
136     'regexp' => {set => 'setregexp', alias => [qw(bm fm)]},
137     'regdata' => {len => 'regdata_cnt'},
138     'regdatum' => {get => 'regdatum_get', set => 'regdatum_set'},
139     'backref' => {free => 'killbackrefs'},
140     'ovrld' => {free => 'freeovrld'},
141     'utf8' => {set => 'setutf8'},
142     'collxfrm' => {set => 'setcollxfrm',
143		    cond => '#ifdef USE_LOCALE_COLLATE'},
144     'hintselem' => {set => 'sethint', clear => 'clearhint'},
145     'hints' => {clear => 'clearhints'},
146     'checkcall' => {copy => 'copycallchecker'},
147);
148
149my ($vt, $raw, $names) = map {
150    open_new($_, '>',
151	     { by => 'regen/mg_vtable.pl', file => $_, style => '*' });
152} 'mg_vtable.h', 'mg_raw.h', 'mg_names.c';
153my $guts = open_new("pod/perlguts.pod", ">");
154
155print $vt <<'EOH';
156/* These constants should be used in preference to raw characters
157 * when using magic. Note that some perl guts still assume
158 * certain character properties of these constants, namely that
159 * isUPPER() and toLOWER() may do useful mappings.
160 */
161
162EOH
163
164# Of course, it would be *much* easier if we could output this table directly
165# here and now. However, for our sins, we try to support EBCDIC, which wouldn't
166# be *so* bad, except that there are (at least) 3 EBCDIC charset variants, and
167# they don't agree on the code point for '~'. Which we use. Great.
168# So we have to get the local build runtime to sort our table in character order
169# (And of course, just to be helpful, in POSIX BC '~' is \xFF, so we can't even
170# simplify the C code by assuming that the last element of the array is
171# predictable)
172
173{
174    my $longest = 0;
175    foreach (keys %mg) {
176	$longest = length $_ if length $_ > $longest;
177    }
178
179    my $longest_p1 = $longest + 1;
180
181    my %mg_order;
182    while (my ($name, $data) = each %mg) {
183	my $byte = eval qq{"$data->{char}"};
184	$data->{byte} = $byte;
185	$mg_order{(uc $byte) . $byte} = $name;
186    }
187    my @rows;
188    foreach (sort keys %mg_order) {
189	my $name = $mg_order{$_};
190	my $data = $mg{$name};
191	my $i = ord $data->{byte};
192	unless ($data->{unknown_to_sv_magic}) {
193	    my $value = $data->{vtable}
194		? "want_vtbl_$data->{vtable}" : 'magic_vtable_max';
195	    $value .= ' | PERL_MAGIC_READONLY_ACCEPTABLE'
196		if $data->{readonly_acceptable};
197	    $value .= ' | PERL_MAGIC_VALUE_MAGIC' if $data->{value_magic};
198	    my $comment = "/* $name '$data->{char}' $data->{desc} */";
199	    $comment =~ s/([\\"])/\\$1/g;
200	    $comment =~ tr/\n/ /;
201	    print $raw qq{    { '$data->{char}', "$value",\n      "$comment" },\n};
202	}
203
204	my $comment = $data->{desc};
205	my $leader = ' ' x ($longest + 27);
206	$comment =~ s/\n/\n$leader/s;
207	printf $vt "#define PERL_MAGIC_%-${longest}s '%s' /* %s */\n",
208	    $name, $data->{char}, $comment;
209
210	my $char = $data->{char};
211	$char =~ s/([\\"])/\\$1/g;
212	printf $names qq[\t{ PERL_MAGIC_%-${longest_p1}s "%s(%s)" },\n],
213	    "$name,", $name, $char;
214
215	push @rows, [(sprintf "%-2s PERL_MAGIC_%s", $data->{char}, $name),
216		     $data->{vtable} ? "vtbl_$data->{vtable}" : '(none)',
217		     $data->{desc}];
218    }
219    select +(select($guts), do {
220	my @header = ('(old-style char and macro)', 'MGVTBL', 'Type of magic');
221	my @widths = (0, 0);
222	foreach my $row (@rows) {
223	    for (0, 1) {
224		$widths[$_] = length $row->[$_]
225		    if length $row->[$_] > $widths[$_];
226	    }
227	}
228	my $indent = ' ';
229	my $format
230	    = sprintf "$indent%%-%ds%%-%ds%%s\n", $widths[0] + 1, $widths[1] + 1;
231	my $desc_wrap =
232	    79 - 7 - (length $indent) - $widths[0] - $widths[1] - 2;
233
234	open my $oldguts, "<", "pod/perlguts.pod"
235	   or die "$0 cannot open pod/perlguts.pod for reading: $!";
236	while (<$oldguts>) {
237	    print;
238	    last if /^=for mg_vtable.pl begin/
239	}
240
241	print "\n", $indent . "mg_type\n";
242	printf $format, @header;
243	printf $format, map {'-' x length $_} @header;
244	foreach (@rows) {
245	    my ($type, $vtbl, $desc) = @$_;
246	    $desc =~ tr/\n/ /;
247	    my @cont;
248	    if (length $desc > $desc_wrap) {
249		# If it's too long, first split on '(', if there.
250		# [Which, if there, is always short enough, currently.
251		# Make this more robust if that changes]
252		($desc, @cont) = split /(?=\()/, $desc;
253		if (!@cont) {
254		    ($desc, @cont) = $desc =~ /(.{1,$desc_wrap})(?: |\z)/g
255		}
256	    }
257	    printf $format, $type, $vtbl, $desc;
258	    printf $format, '', '', $_ foreach @cont;
259	}
260	print "\n";
261
262	while (<$oldguts>) {
263	    last if /^=for mg_vtable.pl end/;
264	}
265	do { print } while <$oldguts>;
266    })[0];
267}
268
269my @names = sort keys %sig;
270{
271    my $want = join ",\n    ", (map {"want_vtbl_$_"} @names), 'magic_vtable_max';
272    my $names = join qq{",\n    "}, @names;
273
274    print $vt <<"EOH";
275
276enum {		/* pass one of these to get_vtbl */
277    $want
278};
279
280#ifdef DOINIT
281EXTCONST char * const PL_magic_vtable_names[magic_vtable_max] = {
282    "$names"
283};
284#else
285EXTCONST char * const PL_magic_vtable_names[magic_vtable_max];
286#endif
287
288EOH
289}
290
291print $vt <<'EOH';
292/* These all need to be 0, not NULL, as NULL can be (void*)0, which is a
293 * pointer to data, whereas we're assigning pointers to functions, which are
294 * not the same beast. ANSI doesn't allow the assignment from one to the other.
295 * (although most, but not all, compilers are prepared to do it)
296 */
297
298/* order is:
299    get
300    set
301    len
302    clear
303    free
304    copy
305    dup
306    local
307*/
308
309#ifdef DOINIT
310EXT_MGVTBL PL_magic_vtables[magic_vtable_max] = {
311EOH
312
313my @vtable_names;
314my @aliases;
315
316while (my $name = shift @names) {
317    my $data = $sig{$name};
318    push @vtable_names, $name;
319    my @funcs = map {
320	$data->{$_} ? "Perl_magic_$data->{$_}" : 0;
321    } qw(get set len clear free copy dup local);
322
323    $funcs[0] = "(int (*)(pTHX_ SV *, MAGIC *))" . $funcs[0] if $data->{const};
324    my $funcs = join ", ", @funcs;
325
326    # Because we can't have a , after the last {...}
327    my $comma = @names ? ',' : '';
328
329    print $vt "$data->{cond}\n" if $data->{cond};
330    print $vt "  { $funcs }$comma\n";
331    print $vt <<"EOH" if $data->{cond};
332#else
333  { 0, 0, 0, 0, 0, 0, 0, 0 }$comma
334#endif
335EOH
336    foreach(@{$data->{alias}}) {
337	push @aliases, "#define want_vtbl_$_ want_vtbl_$name\n";
338	push @vtable_names, $_;
339    }
340}
341
342print $vt <<'EOH';
343};
344#else
345EXT_MGVTBL PL_magic_vtables[magic_vtable_max];
346#endif
347
348EOH
349
350print $vt (sort @aliases), "\n";
351
352print $vt "#define PL_vtbl_$_ PL_magic_vtables[want_vtbl_$_]\n"
353    foreach sort @vtable_names;
354
355# 63, not 64, As we rely on the last possible value to mean "NULL vtable"
356die "Too many vtable names" if @vtable_names > 63;
357
358read_only_bottom_close_and_rename($_) foreach $vt, $raw, $names;
359		 close_and_rename($guts);
360