merge the four parser stacks into one
[p5sagit/p5-mst-13.2.git] / regen_perly.pl
CommitLineData
0de566d7 1#!/usr/bin/perl
2#
3# regen_perly.pl, DAPM 12-Feb-04
4#
1d325971 5# Copyright (c) 2004, 2005 Larry Wall
0de566d7 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.
0de566d7 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
32sub usage { die "usage: $0 [ -b bison_executable ] [ file.y ]\n" }
33
34use warnings;
35use strict;
36
37my $bison = 'bison';
38
39if (@ARGV >= 2 and $ARGV[0] eq '-b') {
40 shift;
41 $bison = shift;
42}
43
44my $y_file = shift || 'perly.y';
45
46usage unless @ARGV==0 && $y_file =~ /\.y$/;
47
48(my $h_file = $y_file) =~ s/\.y$/.h/;
49(my $act_file = $y_file) =~ s/\.y$/.act/;
50(my $tab_file = $y_file) =~ s/\.y$/.tab/;
51(my $tmpc_file = $y_file) =~ s/\.y$/tmp.c/;
52(my $tmph_file = $y_file) =~ s/\.y$/tmp.h/;
53
54# the yytranslate[] table generated by bison is ASCII/EBCDIC sensitive
55
56die "$0: must be run on an ASCII system\n" unless ord 'A' == 65;
57
58# check for correct version number. The constraints are:
59# * must be >= 1.24 to avoid licensing issues.
60# * it must generate the yystos[] table. Version 1.28 doesn't generate
61# this; 1.35+ does
62# * Must produce output which is extractable by the regexes below
63# * Must produce the right values.
64# These last two contstraints may well be met by earlier versions, but
65# I simply haven't tested them yet. If it works for you, then modify
66# the test below to allow that version too. DAPM Feb 04.
67
68my $version = `$bison -V`;
3797f23d 69unless ($version =~ /\b(1\.875[a-z]?|2\.[013])\b/) { die <<EOF; }
0de566d7 70
2080282f 71You have the wrong version of bison in your path; currently 1.875
3797f23d 722.0, 2.1 or 2.3 is required. Try installing
20515881 73 http://ftp.gnu.org/gnu/bison/bison-2.1.tar.gz
0de566d7 74or similar. Your bison identifies itself as:
75
76$version
77EOF
78
79# creates $tmpc_file and $tmph_file
80my_system("$bison -d -o $tmpc_file $y_file");
81
82open CTMPFILE, $tmpc_file or die "Can't open $tmpc_file: $!\n";
83my $clines;
84{ local $/; $clines = <CTMPFILE>; }
85die "failed to read $tmpc_file: length mismatch\n"
86 unless length $clines == -s $tmpc_file;
87close CTMPFILE;
88
89my ($actlines, $tablines) = extract($clines);
90
d5c6462e 91$tablines .= make_type_tab($y_file, $tablines);
0539ab63 92
0de566d7 93chmod 0644, $act_file;
94open ACTFILE, ">$act_file" or die "can't open $act_file: $!\n";
95print ACTFILE $actlines;
96close ACTFILE;
97chmod 0444, $act_file;
98
99chmod 0644, $tab_file;
100open TABFILE, ">$tab_file" or die "can't open $tab_file: $!\n";
101print TABFILE $tablines;
102close TABFILE;
103chmod 0444, $tab_file;
104
105unlink $tmpc_file;
106
107# Wrap PERL_CORE round the symbol definitions. Also, the
96f4e226 108# C<#line 30 "perly.y"> confuses the Win32 resource compiler and the
109# C<#line 188 "perlytmp.h"> gets picked up by make depend, so remove them.
0de566d7 110
111open TMPH_FILE, $tmph_file or die "Can't open $tmph_file: $!\n";
112chmod 0644, $h_file;
113open H_FILE, ">$h_file" or die "Can't open $h_file: $!\n";
114my $endcore_done = 0;
115while (<TMPH_FILE>) {
116 print H_FILE "#ifdef PERL_CORE\n" if $. == 1;
117 if (!$endcore_done and /YYSTYPE_IS_DECLARED/) {
118 print H_FILE "#endif /* PERL_CORE */\n";
119 $endcore_done = 1;
120 }
96f4e226 121 next if /^#line \d+ ".*"/;
0de566d7 122 print H_FILE $_;
123}
124close TMPH_FILE;
125close H_FILE;
126chmod 0444, $h_file;
127unlink $tmph_file;
128
129print "rebuilt: $h_file $tab_file $act_file\n";
130
131exit 0;
132
133
134sub extract {
135 my $clines = shift;
136 my $tablines;
137 my $actlines;
138
139 $clines =~ m@
140 (?:
141 ^/* YYFINAL[^\n]+\n #optional comment
142 )?
143 \# \s* define \s* YYFINAL # first #define
144 .*? # other defines + most tables
145 yystos\[\]\s*= # start of last table
146 .*?
147 }\s*; # end of last table
148 @xms
149 or die "Can't extract tables from $tmpc_file\n";
150 $tablines = $&;
151
152
153 $clines =~ m@
154 switch \s* \( \s* \w+ \s* \) \s* { \s*
155 (
156 case \s* \d+ \s* : \s*
2ade6388 157 \#line [^\n]+"\Q$y_file\E"
0de566d7 158 .*?
159 )
160 }
161 \s*
162 ( \s* /\* .*? \*/ \s* )* # optional C-comments
163 \s*
164 (
165 \#line[^\n]+\.c"
166 |
167 \#line[^\n]+\.simple"
3797f23d 168 |
169 YY_SYMBOL_PRINT
0de566d7 170 )
171 @xms
172 or die "Can't extract actions from $tmpc_file\n";
173 $actlines = $1;
174
0d6f9730 175 # C<#line 188 "perlytmp.c"> gets picked up by make depend, so remove them.
176 $actlines =~ s/^#line \d+ "\Q$tmpc_file\E".*$//gm;
177
1654d593 178 # convert yyvsp[nnn] into ps[nnn].val
179
180 $actlines =~ s/yyvsp\[(.*?)\]/ps[$1].val/g
181 or die "Can't convert value stack name\n";
182
0de566d7 183 return $actlines. "\n", $tablines. "\n";
184}
185
d5c6462e 186# Generate a table, yy_type_tab[], that specifies for each token, what
187# type of value it holds.
0539ab63 188#
d5c6462e 189# Read the .y file and extract a list of all the token names and
190# non-terminal names; then scan the string $tablines for the table yytname,
191# which gives the token index of each token/non-terminal; then use this to
192# create yy_type_tab.
0539ab63 193#
d5c6462e 194# ie given (in perly.y),
195#
196# %token <opval> A
197# %token <ival> B
198# %type <pval> C
199# %type <opval> D
200#
201# and (in $tablines),
202#
203# yytname[] = { "A" "B", "C", "D", "E" };
0539ab63 204#
205# then return
d5c6462e 206#
207# typedef enum { toketype_ival, toketype_opval, toketype_pval } toketypes;
208#
209# static const toketypes yy_type_tab[]
210# = { toketype_opval, toketype_ival, toketype_pval,
211# toketype_opval, toketype_ival }
212#
213# where "E" has the default type. The default type is determined
214# by the __DEFAULT__ comment next to the appropriate union member in
215# perly.y
0539ab63 216
d5c6462e 217sub make_type_tab {
0539ab63 218 my ($y_file, $tablines) = @_;
219 my %tokens;
d5c6462e 220 my %types;
221 my $default_token;
0539ab63 222 open my $fh, '<', $y_file or die "Can't open $y_file: $!\n";
223 while (<$fh>) {
29522234 224 if (/(\$\d+)\s*=/) {
225 warn "$y_file:$.: dangerous assignment to $1: $_";
226 }
227
d5c6462e 228 if (/__DEFAULT__/) {
229 m{(\w+) \s* ; \s* /\* \s* __DEFAULT__}x
230 or die "$y_file: can't parse __DEFAULT__ line: $_";
231 die "$y_file: duplicate __DEFAULT__ line: $_"
232 if defined $default_token;
233 $default_token = $1;
234 next;
235 }
236
237 next unless /^%(token|type)/;
238 s/^%(token|type)\s+<(\w+)>\s+//
239 or die "$y_file: unparseable token/type line: $_";
240 $tokens{$_} = $2 for (split ' ', $_);
241 $types{$2} = 1;
0539ab63 242 }
d5c6462e 243 die "$y_file: no __DEFAULT__ token defined\n" unless $default_token;
244 $types{$default_token} = 1;
0539ab63 245
246 $tablines =~ /^\Qstatic const char *const yytname[] =\E\n
247 {\n
248 (.*?)
249 ^};
250 /xsm
251 or die "Can't extract yytname[] from table string\n";
252 my $fields = $1;
d5c6462e 253 $fields =~ s{"([^"]+)"}
254 { "toketype_" .
255 (defined $tokens{$1} ? $tokens{$1} : $default_token)
256 }ge;
257 $fields =~ s/, \s* 0 \s* $//x
258 or die "make_type_tab: couldn't delete trailing ',0'\n";
259
0539ab63 260 return
d5c6462e 261 "\ntypedef enum {\n\t"
262 . join(", ", map "toketype_$_", sort keys %types)
263 . "\n} toketypes;\n\n"
264 . "/* type of each token/terminal */\n"
d5c6462e 265 . "static const toketypes yy_type_tab[] =\n{\n"
266 . $fields
267 . "\n};\n";
0539ab63 268}
269
270
0de566d7 271sub my_system {
272 system(@_);
273 if ($? == -1) {
d5c6462e 274 die "failed to execute command '@_': $!\n";
0de566d7 275 }
276 elsif ($? & 127) {
277 die sprintf "command '@_' died with signal %d\n",
278 ($? & 127);
279 }
280 elsif ($? >> 8) {
281 die sprintf "command '@_' exited with value %d\n", $? >> 8;
282 }
283}