Check in the pristine copy of ICU 4.6...

icu46/source/i18n/regexcst.pl

+#!/usr/bin/perl
+#  ********************************************************************
+#  * COPYRIGHT:
+#  * Copyright (c) 2002-2007, International Business Machines Corporation and
+#  * others. All Rights Reserved.
+#  ********************************************************************
+#
+#  regexcst.pl
+#            Compile the regular expression paser state table data into initialized C data.
+#            Usage:
+#                   cd icu/source/i18n
+#                   perl regexcst.pl < regexcst.txt > regexcst.h
+#
+#             The output file, regexcst.h, is included by some of the .cpp regex
+#             implementation files.   This perl script is NOT run as part
+#             of a normal ICU build.  It is run by hand when needed, and the
+#             regexcst.h generated file is put back into cvs.
+#
+#             See regexcst.txt for a description of the input format for this script.
+#
+#             This script is derived from rbbicst.pl, which peforms the same function
+#             for the Rule Based Break Iterator Rule Parser.  Perhaps they could be
+#             merged?
+#
+
+
+$num_states = 1;         # Always the state number for the line being compiled.
+$line_num  = 0;          # The line number in the input file.
+
+$states{"pop"} = 255;    # Add the "pop"  to the list of defined state names.
+                         # This prevents any state from being labelled with "pop",
+                         #  and resolves references to "pop" in the next state field.
+
+line_loop: while (<>) {
+    chomp();
+    $line = $_;
+    @fields = split();
+    $line_num++;
+
+    # Remove # comments, which are any fields beginning with a #, plus all
+    #  that follow on the line.
+    for ($i=0; $i<@fields; $i++) {
+        if ($fields[$i] =~ /^#/) {
+            @fields = @fields[0 .. $i-1];
+            last;
+        }
+    }
+    # ignore blank lines, and those with no fields left after stripping comments..
+    if (@fields == 0) {
+        next;
+    }
+
+    #
+    # State Label:  handling.
+    #    Does the first token end with a ":"?  If so, it's the name  of a state.
+    #    Put in a hash, together with the current state number,
+    #        so that we can later look up the number from the name.
+    #
+    if (@fields[0] =~ /.*:$/) {
+        $state_name = @fields[0];
+        $state_name =~ s/://;        # strip off the colon from the state name.
+
+        if ($states{$state_name} != 0) {
+            print "  rbbicst: at line $line-num duplicate definition of state $state_name\n";
+        }
+        $states{$state_name} = $num_states;
+        $stateNames[$num_states] = $state_name;
+
+        # if the label was the only thing on this line, go on to the next line,
+        # otherwise assume that a state definition is on the same line and fall through.
+        if (@fields == 1) {
+            next line_loop;
+        }
+        shift @fields;                       # shift off label field in preparation
+                                             #  for handling the rest of the line.
+    }
+
+    #
+    # State Transition line.
+    #   syntax is this,
+    #       character   [n]  target-state  [^push-state]  [function-name]
+    #   where
+    #      [something]   is an optional something
+    #      character     is either a single quoted character e.g. '['
+    #                       or a name of a character class, e.g. white_space
+    #
+
+    $state_line_num[$num_states] = $line_num;   # remember line number with each state
+                                                #  so we can make better error messages later.
+    #
+    # First field, character class or literal character for this transition.
+    #
+    if ($fields[0] =~ /^'.'$/) {
+        # We've got a quoted literal character.
+        $state_literal_chars[$num_states] = $fields[0];
+        $state_literal_chars[$num_states] =~ s/'//g;
+    } else {
+        # We've got the name of a character class.
+        $state_char_class[$num_states] = $fields[0];
+        if ($fields[0] =~ /[\W]/) {
+            print "  rbbicsts:  at line $line_num, bad character literal or character class name.\n";
+            print "     scanning $fields[0]\n";
+            exit(-1);
+        }
+    }
+    shift @fields;
+
+    #
+    # do the 'n' flag
+    #
+    $state_flag[$num_states] = "FALSE";
+    if ($fields[0] eq "n") {
+        $state_flag[$num_states] = "TRUE";
+        shift @fields;
+    }
+
+    #
+    # do the destination state.
+    #
+    $state_dest_state[$num_states] = $fields[0];
+    if ($fields[0] eq "") {
+        print "  rbbicsts:  at line $line_num, destination state missing.\n";
+        exit(-1);
+    }
+    shift @fields;
+
+    #
+    # do the push state, if present.
+    #
+    if ($fields[0] =~ /^\^/) {
+        $fields[0] =~ s/^\^//;
+        $state_push_state[$num_states] = $fields[0];
+        if ($fields[0] eq "" ) {
+            print "  rbbicsts:  at line $line_num, expected state after ^ (no spaces).\n";
+            exit(-1);
+        }
+        shift @fields;
+    }
+
+    #
+    # Lastly, do the optional action name.
+    #
+    if ($fields[0] ne "") {
+        $state_func_name[$num_states] = $fields[0];
+        shift @fields;
+    }
+
+    #
+    #  There should be no fields left on the line at this point.
+    #
+    if (@fields > 0) {
+       print "  rbbicsts:  at line $line_num, unexpected extra stuff on input line.\n";
+       print "     scanning $fields[0]\n";
+   }
+   $num_states++;
+}
+
+#
+# We've read in the whole file, now go back and output the
+#   C source code for the state transition table.
+#
+# We read all states first, before writing anything,  so that the state numbers
+# for the destination states are all available to be written.
+#
+
+#
+# Make hashes for the names of the character classes and
+#      for the names of the actions that appeared.
+#
+for ($state=1; $state < $num_states; $state++) {
+    if ($state_char_class[$state] ne "") {
+        if ($charClasses{$state_char_class[$state]} == 0) {
+            $charClasses{$state_char_class[$state]} = 1;
+        }
+    }
+    if ($state_func_name[$state] eq "") {
+        $state_func_name[$state] = "doNOP";
+    }
+    if ($actions{$state_action_name[$state]} == 0) {
+        $actions{$state_func_name[$state]} = 1;
+    }
+}
+
+#
+# Check that all of the destination states have been defined
+#
+#
+$states{"exit"} = 0;              # Predefined state name, terminates state machine.
+for ($state=1; $state<$num_states; $state++) {
+   if ($states{$state_dest_state[$state]} == 0 && $state_dest_state[$state] ne "exit") {
+       print "Error at line $state_line_num[$state]: target state \"$state_dest_state[$state]\" is not defined.\n";
+       $errors++;
+   }
+   if ($state_push_state[$state] ne "" && $states{$state_push_state[$state]} == 0) {
+       print "Error at line $state_line_num[$state]: target state \"$state_push_state[$state]\" is not defined.\n";
+       $errors++;
+   }
+}
+
+die if ($errors>0);
+
+print "//---------------------------------------------------------------------------------\n";
+print "//\n";
+print "// Generated Header File.  Do not edit by hand.\n";
+print "//    This file contains the state table for the ICU Regular Expression Pattern Parser\n";
+print "//    It is generated by the Perl script \"regexcst.pl\" from\n";
+print "//    the rule parser state definitions file \"regexcst.txt\".\n";
+print "//\n";
+print "//   Copyright (C) 2002-2007 International Business Machines Corporation \n";
+print "//   and others. All rights reserved.  \n";
+print "//\n";
+print "//---------------------------------------------------------------------------------\n";
+print "#ifndef RBBIRPT_H\n";
+print "#define RBBIRPT_H\n";
+print "\n";
+print "U_NAMESPACE_BEGIN\n";
+
+#
+# Emit the constants for indicies of Unicode Sets
+#   Define one constant for each of the character classes encountered.
+#   At the same time, store the index corresponding to the set name back into hash.
+#
+print "//\n";
+print "// Character classes for regex pattern scanning.\n";
+print "//\n";
+$i = 128;                   # State Table values for Unicode char sets range from 128-250.
+                            # Sets "default", "quoted", etc. get special handling.
+                            #  They have no corresponding UnicodeSet object in the state machine,
+                            #    but are handled by special case code.  So we emit no reference
+                            #    to a UnicodeSet object to them here.
+foreach $setName (keys %charClasses) {
+    if ($setName eq "default") {
+        $charClasses{$setName} = 255;}
+    elsif ($setName eq "quoted") {
+        $charClasses{$setName} = 254;}
+    elsif ($setName eq "eof") {
+        $charClasses{$setName} = 253;}
+    else {
+        # Normal character class.  Fill in array with a ptr to the corresponding UnicodeSet in the state machine.
+       print "    static const uint8_t kRuleSet_$setName = $i;\n";
+        $charClasses{$setName} = $i;
+        $i++;
+    }
+}
+print "\n\n";
+
+#
+# Emit the enum for the actions to be performed.
+#
+print "enum Regex_PatternParseAction {\n";
+foreach $act (keys %actions) {
+    print "    $act,\n";
+}
+print "    rbbiLastAction};\n\n";
+
+#
+# Emit the struct definition for transtion table elements.
+#
+print "//-------------------------------------------------------------------------------\n";
+print "//\n";
+print "//  RegexTableEl       represents the structure of a row in the transition table\n";
+print "//                     for the pattern parser state machine.\n";
+print "//-------------------------------------------------------------------------------\n";
+print "struct RegexTableEl {\n";
+print "    Regex_PatternParseAction      fAction;\n";
+print "    uint8_t                       fCharClass;       // 0-127:    an individual ASCII character\n";
+print "                                                    // 128-255:  character class index\n";
+print "    uint8_t                       fNextState;       // 0-250:    normal next-state numbers\n";
+print "                                                    // 255:      pop next-state from stack.\n";
+print "    uint8_t                       fPushState;\n";
+print "    UBool                         fNextChar;\n";
+print "};\n\n";
+
+#
+# emit the state transition table
+#
+print "static const struct RegexTableEl gRuleParseStateTable[] = {\n";
+print "    {doNOP, 0, 0, 0, TRUE}\n";    # State 0 is a dummy.  Real states start with index = 1.
+for ($state=1; $state < $num_states; $state++) {
+    print "    , {$state_func_name[$state],";
+    if ($state_literal_chars[$state] ne "") {
+        $c = $state_literal_chars[$state];
+        printf(" %d /* $c */,", ord($c));   #  use numeric value, so EBCDIC machines are ok.
+    }else {
+        print " $charClasses{$state_char_class[$state]},";
+    }
+    print " $states{$state_dest_state[$state]},";
+
+    # The push-state field is optional.  If omitted, fill field with a zero, which flags
+    #   the state machine that there is no push state.
+    if ($state_push_state[$state] eq "") {
+        print "0, ";
+    } else {
+        print " $states{$state_push_state[$state]},";
+    }
+    print " $state_flag[$state]} ";
+
+    # Put out a C++ comment showing the number (index) of this state row,
+    #   and, if this is the first row of the table for this state, the state name.
+    print "    //  $state ";
+    if ($stateNames[$state] ne "") {
+        print "     $stateNames[$state]";
+    }
+    print "\n";
+};
+print " };\n";
+
+
+#
+# emit a mapping array from state numbers to state names.
+#
+#    This array is used for producing debugging output from the pattern parser.
+#
+print "static const char * const RegexStateNames[] = {";
+for ($state=0; $state<$num_states; $state++) {
+    if ($stateNames[$state] ne "") {
+        print "     \"$stateNames[$state]\",\n";
+    } else {
+        print "    0,\n";
+    }
+}
+print "    0};\n\n";
+
+print "U_NAMESPACE_END\n";
+print "#endif\n";
+
+
+