1#!/usr/bin/perl 2# 3# regen_perly.pl, DAPM 12-Feb-04 4# 5# Copyright (c) 2004, 2005 Larry Wall 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 14# plus an extra table generated by this script. 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`; 69unless ($version =~ /\b(1\.875[a-z]?|2\.[0134])\b/) { die <<EOF; } 70 71You have the wrong version of bison in your path; currently 1.875 722.0, 2.1, 2.3 or 2.4 is required. Try installing 73 http://ftp.gnu.org/gnu/bison/bison-2.4.1.tar.gz 74or similar. Your bison identifies itself as: 75 76$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 91$tablines .= make_type_tab($y_file, $tablines); 92 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 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. 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; 115# Token macros need to be generated manually on bison 2.4 116my $gather_tokens = ($version =~ /\b2\.4\b/ ? undef : 0); 117my $tokens; 118while (<TMPH_FILE>) { 119 print H_FILE "#ifdef PERL_CORE\n" if $. == 1; 120 if (!$endcore_done and /YYSTYPE_IS_DECLARED/) { 121 print H_FILE "#endif /* PERL_CORE */\n"; 122 $endcore_done = 1; 123 } 124 next if /^#line \d+ ".*"/; 125 if (not defined $gather_tokens) { 126 $gather_tokens = 1 if /^\s* enum \s* yytokentype \s* \{/x; 127 } 128 elsif ($gather_tokens) { 129 if (/^\# \s* endif/x) { # The #endif just after the end of the token enum 130 $gather_tokens = 0; 131 $_ .= "\n/* Tokens. */\n$tokens"; 132 } 133 else { 134 my ($tok, $val) = /(\w+) \s* = \s* (\d+)/x; 135 $tokens .= "#define $tok $val\n" if $tok; 136 } 137 } 138 print H_FILE $_; 139} 140close TMPH_FILE; 141close H_FILE; 142chmod 0444, $h_file; 143unlink $tmph_file; 144 145print "rebuilt: $h_file $tab_file $act_file\n"; 146 147exit 0; 148 149 150sub extract { 151 my $clines = shift; 152 my $tablines; 153 my $actlines; 154 155 $clines =~ m@ 156 (?: 157 ^/* YYFINAL[^\n]+\n #optional comment 158 )? 159 \# \s* define \s* YYFINAL # first #define 160 .*? # other defines + most tables 161 yystos\[\]\s*= # start of last table 162 .*? 163 }\s*; # end of last table 164 @xms 165 or die "Can't extract tables from $tmpc_file\n"; 166 $tablines = $&; 167 168 169 $clines =~ m@ 170 switch \s* \( \s* \w+ \s* \) \s* { \s* 171 ( 172 case \s* \d+ \s* : 173 \s* 174 (?: \s* /\* .*? \*/ \s* )* # optional C-comments 175 \s* 176 \#line [^\n]+"\Q$y_file\E" 177 .*? 178 ) 179 } 180 \s* 181 (?: \s* /\* .*? \*/ \s* )* # optional C-comments 182 \s* 183 ( 184 \#line[^\n]+\.c" 185 | 186 \#line[^\n]+\.simple" 187 | 188 YY_SYMBOL_PRINT 189 ) 190 @xms 191 or die "Can't extract actions from $tmpc_file\n"; 192 $actlines = $1; 193 194 # Remove extraneous comments from bison 2.4 195 $actlines =~ s!\s* /\* \s* Line \s* \d+ \s* of \s* yacc\.c \s* \*/!!gx; 196 197 # C<#line 188 "perlytmp.c"> gets picked up by make depend, so remove them. 198 $actlines =~ s/^#line \d+ "\Q$tmpc_file\E".*$//gm; 199 200 # convert yyvsp[nnn] into ps[nnn].val 201 202 $actlines =~ s/yyvsp\[(.*?)\]/ps[$1].val/g 203 or die "Can't convert value stack name\n"; 204 205 return $actlines. "\n", $tablines. "\n"; 206} 207 208# Generate a table, yy_type_tab[], that specifies for each token, what 209# type of value it holds. 210# 211# Read the .y file and extract a list of all the token names and 212# non-terminal names; then scan the string $tablines for the table yytname, 213# which gives the token index of each token/non-terminal; then use this to 214# create yy_type_tab. 215# 216# ie given (in perly.y), 217# 218# %token <opval> A 219# %token <ival> B 220# %type <pval> C 221# %type <opval> D 222# 223# and (in $tablines), 224# 225# yytname[] = { "A" "B", "C", "D", "E" }; 226# 227# then return 228# 229# typedef enum { toketype_ival, toketype_opval, toketype_pval } toketypes; 230# 231# static const toketypes yy_type_tab[] 232# = { toketype_opval, toketype_ival, toketype_pval, 233# toketype_opval, toketype_ival } 234# 235# where "E" has the default type. The default type is determined 236# by the __DEFAULT__ comment next to the appropriate union member in 237# perly.y 238 239sub make_type_tab { 240 my ($y_file, $tablines) = @_; 241 my %tokens; 242 my %types; 243 my $default_token; 244 open my $fh, '<', $y_file or die "Can't open $y_file: $!\n"; 245 while (<$fh>) { 246 if (/(\$\d+)\s*=/) { 247 warn "$y_file:$.: dangerous assignment to $1: $_"; 248 } 249 250 if (/__DEFAULT__/) { 251 m{(\w+) \s* ; \s* /\* \s* __DEFAULT__}x 252 or die "$y_file: can't parse __DEFAULT__ line: $_"; 253 die "$y_file: duplicate __DEFAULT__ line: $_" 254 if defined $default_token; 255 $default_token = $1; 256 next; 257 } 258 259 next unless /^%(token|type)/; 260 s/^%(token|type)\s+<(\w+)>\s+// 261 or die "$y_file: unparseable token/type line: $_"; 262 $tokens{$_} = $2 for (split ' ', $_); 263 $types{$2} = 1; 264 } 265 die "$y_file: no __DEFAULT__ token defined\n" unless $default_token; 266 $types{$default_token} = 1; 267 268 $tablines =~ /^\Qstatic const char *const yytname[] =\E\n 269 {\n 270 (.*?) 271 ^}; 272 /xsm 273 or die "Can't extract yytname[] from table string\n"; 274 my $fields = $1; 275 $fields =~ s{"([^"]+)"} 276 { "toketype_" . 277 (defined $tokens{$1} ? $tokens{$1} : $default_token) 278 }ge; 279 $fields =~ s/, \s* 0 \s* $//x 280 or die "make_type_tab: couldn't delete trailing ',0'\n"; 281 282 return 283 "\ntypedef enum {\n\t" 284 . join(", ", map "toketype_$_", sort keys %types) 285 . "\n} toketypes;\n\n" 286 . "/* type of each token/terminal */\n" 287 . "static const toketypes yy_type_tab[] =\n{\n" 288 . $fields 289 . "\n};\n"; 290} 291 292 293sub my_system { 294 system(@_); 295 if ($? == -1) { 296 die "failed to execute command '@_': $!\n"; 297 } 298 elsif ($? & 127) { 299 die sprintf "command '@_' died with signal %d\n", 300 ($? & 127); 301 } 302 elsif ($? >> 8) { 303 die sprintf "command '@_' exited with value %d\n", $? >> 8; 304 } 305} 306