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Output "read only" editor blocks from regen_perly.pl
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1#!/usr/bin/perl
2#
3# regen_perly.pl, DAPM 12-Feb-04
4#
1d325971 5# Copyright (c) 2004, 2005 Larry Wall
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6#
7# Given an input file perly.y, run bison on it and produce
8# the following output files:
9#
10# perly.h standard bison header file with minor doctoring of
11# #line directives plus adding a #ifdef PERL_CORE
12#
13# perly.tab the parser table C definitions extracted from the bison output
0539ab63 14# plus an extra table generated by this script.
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15#
16# perly.act the action case statements extracted from the bison output
17#
18# Note that perly.c is *not* regenerated - this is now a static file which
19# is not dependent on perly.y any more.
20#
21# If a filename of the form foo.y is given on the command line, then
22# this is used instead as the basename for all the files mentioned
23# above.
24#
25# Note that temporary files of the form perlytmp.h and perlytmp.c are
26# created and then deleted during this process
27#
28# Note also that this script is intended to be run on a UNIX system;
29# it may work elsewhere but no specific attempt has been made to make it
30# portable.
31
e8fb9efb 32use 5.006;
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33sub usage { die "usage: $0 [ -b bison_executable ] [ file.y ]\n" }
34
35use warnings;
36use strict;
37
2bd4012d 38BEGIN { require 'regen/regen_lib.pl'; }
a9718e07 39
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40my $bison = 'bison';
41
42if (@ARGV >= 2 and $ARGV[0] eq '-b') {
43 shift;
44 $bison = shift;
45}
46
47my $y_file = shift || 'perly.y';
48
49usage unless @ARGV==0 && $y_file =~ /\.y$/;
50
51(my $h_file = $y_file) =~ s/\.y$/.h/;
52(my $act_file = $y_file) =~ s/\.y$/.act/;
53(my $tab_file = $y_file) =~ s/\.y$/.tab/;
54(my $tmpc_file = $y_file) =~ s/\.y$/tmp.c/;
55(my $tmph_file = $y_file) =~ s/\.y$/tmp.h/;
56
57# the yytranslate[] table generated by bison is ASCII/EBCDIC sensitive
58
59die "$0: must be run on an ASCII system\n" unless ord 'A' == 65;
60
61# check for correct version number. The constraints are:
62# * must be >= 1.24 to avoid licensing issues.
63# * it must generate the yystos[] table. Version 1.28 doesn't generate
64# this; 1.35+ does
65# * Must produce output which is extractable by the regexes below
66# * Must produce the right values.
8abc1060 67# These last two constraints may well be met by earlier versions, but
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68# I simply haven't tested them yet. If it works for you, then modify
69# the test below to allow that version too. DAPM Feb 04.
70
71my $version = `$bison -V`;
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72unless ($version) { die <<EOF; }
73Could not find a version of bison in your path. Please install bison.
74EOF
75
ce1534ab 76unless ($version =~ /\b(1\.875[a-z]?|2\.[0134])\b/) { die <<EOF; }
0de566d7 77
2080282f 78You have the wrong version of bison in your path; currently 1.875
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792.0, 2.1, 2.3 or 2.4 is required. Try installing
80 http://ftp.gnu.org/gnu/bison/bison-2.4.1.tar.gz
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81or similar. Your bison identifies itself as:
82
83$version
84EOF
85
86# creates $tmpc_file and $tmph_file
87my_system("$bison -d -o $tmpc_file $y_file");
88
e8fb9efb 89open my $ctmp_fh, '<', $tmpc_file or die "Can't open $tmpc_file: $!\n";
0de566d7 90my $clines;
e8fb9efb 91{ local $/; $clines = <$ctmp_fh>; }
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92die "failed to read $tmpc_file: length mismatch\n"
93 unless length $clines == -s $tmpc_file;
e8fb9efb 94close $ctmp_fh;
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95
96my ($actlines, $tablines) = extract($clines);
97
d5c6462e 98$tablines .= make_type_tab($y_file, $tablines);
0539ab63 99
e8fb9efb 100my $read_only = read_only_top(lang => 'C', by => $0, from => $y_file);
0de566d7 101
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102my $act_fh = safer_open("$act_file-new", $act_file);
103print $act_fh $read_only, $actlines;
104read_only_bottom_close_and_rename($act_fh);
105
106my $tab_fh = safer_open("$tab_file-new", $tab_file);
107print $tab_fh $read_only, $tablines;
108read_only_bottom_close_and_rename($tab_fh);
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109
110unlink $tmpc_file;
111
112# Wrap PERL_CORE round the symbol definitions. Also, the
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113# C<#line 30 "perly.y"> confuses the Win32 resource compiler and the
114# C<#line 188 "perlytmp.h"> gets picked up by make depend, so remove them.
0de566d7 115
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116open my $tmph_fh, '<', $tmph_file or die "Can't open $tmph_file: $!\n";
117my $h_fh = safer_open("$h_file-new", $h_file);
118
119print $h_fh $read_only;
120
0de566d7 121my $endcore_done = 0;
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122# Token macros need to be generated manually on bison 2.4
123my $gather_tokens = ($version =~ /\b2\.4\b/ ? undef : 0);
124my $tokens;
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125while (<$tmph_fh>) {
126 print $h_fh "#ifdef PERL_CORE\n" if $. == 1;
0de566d7 127 if (!$endcore_done and /YYSTYPE_IS_DECLARED/) {
e8fb9efb 128 print $h_fh "#endif /* PERL_CORE */\n";
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129 $endcore_done = 1;
130 }
96f4e226 131 next if /^#line \d+ ".*"/;
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132 if (not defined $gather_tokens) {
133 $gather_tokens = 1 if /^\s* enum \s* yytokentype \s* \{/x;
134 }
135 elsif ($gather_tokens) {
136 if (/^\# \s* endif/x) { # The #endif just after the end of the token enum
137 $gather_tokens = 0;
138 $_ .= "\n/* Tokens. */\n$tokens";
139 }
140 else {
141 my ($tok, $val) = /(\w+) \s* = \s* (\d+)/x;
142 $tokens .= "#define $tok $val\n" if $tok;
143 }
144 }
e8fb9efb 145 print $h_fh $_;
0de566d7 146}
e8fb9efb 147close $tmph_fh;
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148unlink $tmph_file;
149
e8fb9efb 150read_only_bottom_close_and_rename($h_fh);
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151
152exit 0;
153
154
155sub extract {
156 my $clines = shift;
157 my $tablines;
158 my $actlines;
159
160 $clines =~ m@
161 (?:
162 ^/* YYFINAL[^\n]+\n #optional comment
163 )?
164 \# \s* define \s* YYFINAL # first #define
165 .*? # other defines + most tables
166 yystos\[\]\s*= # start of last table
167 .*?
168 }\s*; # end of last table
169 @xms
170 or die "Can't extract tables from $tmpc_file\n";
171 $tablines = $&;
172
173
174 $clines =~ m@
175 switch \s* \( \s* \w+ \s* \) \s* { \s*
176 (
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177 case \s* \d+ \s* :
178 \s*
179 (?: \s* /\* .*? \*/ \s* )* # optional C-comments
180 \s*
2ade6388 181 \#line [^\n]+"\Q$y_file\E"
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182 .*?
183 )
184 }
185 \s*
ce1534ab 186 (?: \s* /\* .*? \*/ \s* )* # optional C-comments
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187 \s*
188 (
189 \#line[^\n]+\.c"
190 |
191 \#line[^\n]+\.simple"
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192 |
193 YY_SYMBOL_PRINT
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194 )
195 @xms
196 or die "Can't extract actions from $tmpc_file\n";
197 $actlines = $1;
198
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199 # Remove extraneous comments from bison 2.4
200 $actlines =~ s!\s* /\* \s* Line \s* \d+ \s* of \s* yacc\.c \s* \*/!!gx;
201
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202 # C<#line 188 "perlytmp.c"> gets picked up by make depend, so remove them.
203 $actlines =~ s/^#line \d+ "\Q$tmpc_file\E".*$//gm;
204
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205 # convert yyvsp[nnn] into ps[nnn].val
206
207 $actlines =~ s/yyvsp\[(.*?)\]/ps[$1].val/g
208 or die "Can't convert value stack name\n";
209
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210 return $actlines. "\n", $tablines. "\n";
211}
212
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213# Generate a table, yy_type_tab[], that specifies for each token, what
214# type of value it holds.
0539ab63 215#
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216# Read the .y file and extract a list of all the token names and
217# non-terminal names; then scan the string $tablines for the table yytname,
218# which gives the token index of each token/non-terminal; then use this to
219# create yy_type_tab.
0539ab63 220#
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221# ie given (in perly.y),
222#
223# %token <opval> A
224# %token <ival> B
225# %type <pval> C
226# %type <opval> D
227#
228# and (in $tablines),
229#
230# yytname[] = { "A" "B", "C", "D", "E" };
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231#
232# then return
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233#
234# typedef enum { toketype_ival, toketype_opval, toketype_pval } toketypes;
235#
236# static const toketypes yy_type_tab[]
237# = { toketype_opval, toketype_ival, toketype_pval,
238# toketype_opval, toketype_ival }
239#
240# where "E" has the default type. The default type is determined
241# by the __DEFAULT__ comment next to the appropriate union member in
242# perly.y
0539ab63 243
d5c6462e 244sub make_type_tab {
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245 my ($y_file, $tablines) = @_;
246 my %tokens;
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247 my %types;
248 my $default_token;
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249 open my $fh, '<', $y_file or die "Can't open $y_file: $!\n";
250 while (<$fh>) {
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251 if (/(\$\d+)\s*=/) {
252 warn "$y_file:$.: dangerous assignment to $1: $_";
253 }
254
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255 if (/__DEFAULT__/) {
256 m{(\w+) \s* ; \s* /\* \s* __DEFAULT__}x
257 or die "$y_file: can't parse __DEFAULT__ line: $_";
258 die "$y_file: duplicate __DEFAULT__ line: $_"
259 if defined $default_token;
260 $default_token = $1;
261 next;
262 }
263
264 next unless /^%(token|type)/;
265 s/^%(token|type)\s+<(\w+)>\s+//
266 or die "$y_file: unparseable token/type line: $_";
267 $tokens{$_} = $2 for (split ' ', $_);
268 $types{$2} = 1;
0539ab63 269 }
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270 die "$y_file: no __DEFAULT__ token defined\n" unless $default_token;
271 $types{$default_token} = 1;
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272
273 $tablines =~ /^\Qstatic const char *const yytname[] =\E\n
274 {\n
275 (.*?)
276 ^};
277 /xsm
278 or die "Can't extract yytname[] from table string\n";
279 my $fields = $1;
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280 $fields =~ s{"([^"]+)"}
281 { "toketype_" .
282 (defined $tokens{$1} ? $tokens{$1} : $default_token)
283 }ge;
284 $fields =~ s/, \s* 0 \s* $//x
285 or die "make_type_tab: couldn't delete trailing ',0'\n";
286
0539ab63 287 return
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288 "\ntypedef enum {\n\t"
289 . join(", ", map "toketype_$_", sort keys %types)
290 . "\n} toketypes;\n\n"
291 . "/* type of each token/terminal */\n"
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292 . "static const toketypes yy_type_tab[] =\n{\n"
293 . $fields
294 . "\n};\n";
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295}
296
297
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298sub my_system {
299 system(@_);
300 if ($? == -1) {
d5c6462e 301 die "failed to execute command '@_': $!\n";
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302 }
303 elsif ($? & 127) {
304 die sprintf "command '@_' died with signal %d\n",
305 ($? & 127);
306 }
307 elsif ($? >> 8) {
308 die sprintf "command '@_' exited with value %d\n", $? >> 8;
309 }
310}