X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2FExtUtils%2FConstant.pm;h=91e9b1d1e4d814f6008e4155a70acaa47739f32d;hb=661290c7db36a7818cda2823da4006a4dc9c8cd1;hp=cb3931821d7a3b5c2f94a48994322eaf3e717592;hpb=9a7df4f2d158d129a2431038d4b082ffde8d4bfe;p=p5sagit%2Fp5-mst-13.2.git

diff --git a/lib/ExtUtils/Constant.pm b/lib/ExtUtils/Constant.pm
index cb39318..91e9b1d 100644
--- a/lib/ExtUtils/Constant.pm
+++ b/lib/ExtUtils/Constant.pm
@@ -1,6 +1,6 @@
 package ExtUtils::Constant;
-use vars qw (@ISA $VERSION %XS_Constant %XS_TypeSet @EXPORT_OK %EXPORT_TAGS);
-$VERSION = '0.10';
+use vars qw (@ISA $VERSION @EXPORT_OK %EXPORT_TAGS);
+$VERSION = 0.21;
 
 =head1 NAME
 
@@ -12,8 +12,6 @@ ExtUtils::Constant - generate XS code to import C header constants
     WriteConstants(
         NAME => 'Foo',
         NAMES => [qw(FOO BAR BAZ)],
-        C_FILE => 'constants.c',
-        XS_FILE => 'constants.xs',
     );
     # Generates wrapper code to make the values of the constants FOO BAR BAZ
     #  available to perl
@@ -30,11 +28,11 @@ constants.
 
 Generally one only needs to call the C<WriteConstants> function, and then
 
-    #include "constants.c"
+    #include "const-c.inc"
 
 in the C section of C<Foo.xs>
 
-    INCLUDE constants.xs
+    INCLUDE: const-xs.inc
 
 in the XS section of C<Foo.xs>.
 
@@ -96,12 +94,11 @@ if ($] >= 5.006) {
   eval "use warnings; 1" or die $@;
 }
 use strict;
-use Carp;
+use Carp qw(croak cluck);
 
 use Exporter;
-use Text::Wrap;
-$Text::Wrap::huge = 'overflow';
-$Text::Wrap::columns = 80;
+use ExtUtils::Constant::Utils qw(C_stringify);
+use ExtUtils::Constant::XS qw(%XS_Constant %XS_TypeSet);
 
 @ISA = 'Exporter';
 
@@ -112,61 +109,6 @@ $Text::Wrap::columns = 80;
 
 @EXPORT_OK = ( @{ $EXPORT_TAGS{'all'} } );
 
-%XS_Constant = (
-		IV    => 'PUSHi(iv)',
-		UV    => 'PUSHu((UV)iv)',
-		NV    => 'PUSHn(nv)',
-		PV    => 'PUSHp(pv, strlen(pv))',
-		PVN   => 'PUSHp(pv, iv)',
-		SV    => 'PUSHs(sv)',
-		YES   => 'PUSHs(&PL_sv_yes)',
-		NO    => 'PUSHs(&PL_sv_no)',
-		UNDEF => '',	# implicit undef
-);
-
-%XS_TypeSet = (
-		IV    => '*iv_return =',
-		UV    => '*iv_return = (IV)',
-		NV    => '*nv_return =',
-		PV    => '*pv_return =',
-		PVN   => ['*pv_return =', '*iv_return = (IV)'],
-		SV    => '*sv_return = ',
-		YES   => undef,
-		NO    => undef,
-		UNDEF => undef,
-);
-
-
-=item C_stringify NAME
-
-A function which returns a correctly \ escaped version of the string passed
-suitable for C's "" or ''.  It will also be valid as a perl "" string.
-
-=cut
-
-# Hopefully make a happy C identifier.
-sub C_stringify {
-  local $_ = shift;
-  return unless defined $_;
-  s/\\/\\\\/g;
-  s/([\"\'])/\\$1/g;	# Grr. fix perl mode.
-  s/\n/\\n/g;		# Ensure newlines don't end up in octal
-  s/\r/\\r/g;
-  s/\t/\\t/g;
-  s/\f/\\f/g;
-  s/\a/\\a/g;
-  unless ($] < 5.006) {
-    # This will elict a warning on 5.005_03 about [: :] being reserved unless
-    # I cheat
-    my $cheat = '([[:^print:]])';
-    s/$cheat/sprintf "\\%03o", ord $1/ge;
-  } else {
-    require POSIX;
-    s/([^A-Za-z0-9_])/POSIX::isprint($1) ? $1 : sprintf "\\%03o", ord $1/ge;
-  }
-  $_;
-}
-
 =item constant_types
 
 A function returning a single scalar with C<#define> definitions for the
@@ -174,669 +116,37 @@ constants used internally between the generated C and XS functions.
 
 =cut
 
-sub constant_types () {
-  my $start = 1;
-  my @lines;
-  push @lines, "#define PERL_constant_NOTFOUND\t$start\n"; $start++;
-  push @lines, "#define PERL_constant_NOTDEF\t$start\n"; $start++;
-  foreach (sort keys %XS_Constant) {
-    push @lines, "#define PERL_constant_IS$_\t$start\n"; $start++;
-  }
-  push @lines, << 'EOT';
-
-#ifndef NVTYPE
-typedef double NV; /* 5.6 and later define NVTYPE, and typedef NV to it.  */
-#endif
-#ifndef aTHX_
-#define aTHX_ /* 5.6 or later define this for threading support.  */
-#endif
-#ifndef pTHX_
-#define pTHX_ /* 5.6 or later define this for threading support.  */
-#endif
-EOT
-
-  return join '', @lines;
+sub constant_types {
+  ExtUtils::Constant::XS->header();
 }
 
-=item memEQ_clause NAME, CHECKED_AT, INDENT
-
-A function to return a suitable C C<if> statement to check whether I<NAME>
-is equal to the C variable C<name>. If I<CHECKED_AT> is defined, then it
-is used to avoid C<memEQ> for short names, or to generate a comment to
-highlight the position of the character in the C<switch> statement.
-
-=cut
-
 sub memEQ_clause {
-#    if (memEQ(name, "thingy", 6)) {
-  # Which could actually be a character comparison or even ""
-  my ($name, $checked_at, $indent) = @_;
-  $indent = ' ' x ($indent || 4);
-  my $len = length $name;
-
-  if ($len < 2) {
-    return $indent . "{\n" if (defined $checked_at and $checked_at == 0);
-    # We didn't switch, drop through to the code for the 2 character string
-    $checked_at = 1;
-  }
-  if ($len < 3 and defined $checked_at) {
-    my $check;
-    if ($checked_at == 1) {
-      $check = 0;
-    } elsif ($checked_at == 0) {
-      $check = 1;
-    }
-    if (defined $check) {
-      my $char = C_stringify (substr $name, $check, 1);
-      return $indent . "if (name[$check] == '$char') {\n";
-    }
-  }
-  # Could optimise a memEQ on 3 to 2 single character checks here
-  $name = C_stringify ($name);
-  my $body = $indent . "if (memEQ(name, \"$name\", $len)) {\n";
-    $body .= $indent . "/*               ". (' ' x $checked_at) . '^'
-      . (' ' x ($len - $checked_at + length $len)) . "    */\n"
-        if defined $checked_at;
-  return $body;
+  cluck "ExtUtils::Constant::memEQ_clause is deprecated";
+  ExtUtils::Constant::XS->memEQ_clause({name=>$_[0], checked_at=>$_[1],
+					indent=>$_[2]});
 }
 
-=item assign INDENT, TYPE, PRE, POST, VALUE...
-
-A function to return a suitable assignment clause. If I<TYPE> is aggregate
-(eg I<PVN> expects both pointer and length) then there should be multiple
-I<VALUE>s for the components. I<PRE> and I<POST> if defined give snippets
-of C code to preceed and follow the assignment. I<PRE> will be at the start
-of a block, so variables may be defined in it.
-
-=cut
-
-# Hmm. value undef to to NOTDEF? value () to do NOTFOUND?
-
-sub assign {
+sub return_clause ($$) {
+  cluck "ExtUtils::Constant::return_clause is deprecated";
   my $indent = shift;
-  my $type = shift;
-  my $pre = shift;
-  my $post = shift || '';
-  my $clause;
-  my $close;
-  if ($pre) {
-    chomp $pre;
-    $clause = $indent . "{\n$pre";
-    $clause .= ";" unless $pre =~ /;$/;
-    $clause .= "\n";
-    $close = "$indent}\n";
-    $indent .= "  ";
-  }
-  die "Can't generate code for type $type" unless exists $XS_TypeSet{$type};
-  my $typeset = $XS_TypeSet{$type};
-  if (ref $typeset) {
-    die "Type $type is aggregate, but only single value given"
-      if @_ == 1;
-    foreach (0 .. $#$typeset) {
-      $clause .= $indent . "$typeset->[$_] $_[$_];\n";
-    }
-  } elsif (defined $typeset) {
-    die "Aggregate value given for type $type"
-      if @_ > 1;
-    $clause .= $indent . "$typeset $_[0];\n";
-  }
-  chomp $post;
-  if (length $post) {
-    $clause .= "$post";
-    $clause .= ";" unless $post =~ /;$/;
-    $clause .= "\n";
-  }
-  $clause .= "${indent}return PERL_constant_IS$type;\n";
-  $clause .= $close if $close;
-  return $clause;
+  ExtUtils::Constant::XS->return_clause({indent=>$indent}, @_);
 }
 
-=item return_clause
-
-return_clause VALUE, TYPE, INDENT, MACRO, DEFAULT, PRE, POST, PRE, POST
-
-A function to return a suitable C<#ifdef> clause. I<MACRO> defaults to
-I<VALUE> when not defined.  If I<TYPE> is aggregate (eg I<PVN> expects both
-pointer and length) then I<VALUE> should be a reference to an array of
-values in the order expected by the type.  C<C_constant> will always call
-this function with I<MACRO> defined, defaulting to the constant's name.
-I<DEFAULT> if defined is an array reference giving default type and and
-value(s) if the clause generated by I<MACRO> doesn't evaluate to true.
-The two pairs I<PRE> and I<POST> if defined give C code snippets to proceed
-and follow the value, and the default value.
-
-=cut
-
-sub return_clause ($$$$$$$$$) {
-##ifdef thingy
-#      *iv_return = thingy;
-#      return PERL_constant_ISIV;
-##else
-#      return PERL_constant_NOTDEF;
-##endif
-  my ($value, $type, $indent, $macro, $default, $pre, $post,
-      $def_pre, $def_post) = @_;
-  $macro = $value unless defined $macro;
-  $indent = ' ' x ($indent || 6);
-
-  my $clause;
-
-  ##ifdef thingy
-  if (ref $macro) {
-    $clause = $macro->[0];
-  } elsif ($macro ne "1") {
-    $clause = "#ifdef $macro\n";
-  }
-
-  #      *iv_return = thingy;
-  #      return PERL_constant_ISIV;
-  $clause .= assign ($indent, $type, $pre, $post,
-                     ref $value ? @$value : $value);
-
-  if (ref $macro or $macro ne "1") {
-    ##else
-    $clause .= "#else\n";
-
-    #      return PERL_constant_NOTDEF;
-    if (!defined $default) {
-      $clause .= "${indent}return PERL_constant_NOTDEF;\n";
-    } else {
-      my @default = ref $default ? @$default : $default;
-      $type = shift @default;
-      $clause .= assign ($indent, $type, $def_pre, $def_post, @default);
-    }
-
-    ##endif
-    if (ref $macro) {
-      $clause .= $macro->[1];
-    } else {
-      $clause .= "#endif\n";
-    }
-  }
-  return $clause
-}
-
-=item switch_clause INDENT, NAMELEN, ITEMHASH, ITEM...
-
-An internal function to generate a suitable C<switch> clause, called by
-C<C_constant> I<ITEM>s are in the hash ref format as given in the description
-of C<C_constant>, and must all have the names of the same length, given by
-I<NAMELEN> (This is not checked).  I<ITEMHASH> is a reference to a hash,
-keyed by name, values being the hashrefs in the I<ITEM> list.
-(No parameters are modified, and there can be keys in the I<ITEMHASH> that
-are not in the list of I<ITEM>s without causing problems).
-
-=cut
-
 sub switch_clause {
-  my ($indent, $comment, $namelen, $items, @items) = @_;
-  $indent = ' ' x ($indent || 2);
-
-  my @names = sort map {$_->{name}} @items;
-  my $leader = $indent . '/* ';
-  my $follower = ' ' x length $leader;
-  my $body = $indent . "/* Names all of length $namelen.  */\n";
-  if ($comment) {
-    $body = wrap ($leader, $follower, $comment) . "\n";
-    $leader = $follower;
-  }
-  $body .= wrap ($leader, $follower, join (" ", @names) . " */") . "\n";
-  # Figure out what to switch on.
-  # (RMS, Spread of jump table, Position, Hashref)
-  my @best = (1e38, ~0);
-  foreach my $i (0 .. ($namelen - 1)) {
-    my ($min, $max) = (~0, 0);
-    my %spread;
-    foreach (@names) {
-      my $char = substr $_, $i, 1;
-      my $ord = ord $char;
-      $max = $ord if $ord > $max;
-      $min = $ord if $ord < $min;
-      push @{$spread{$char}}, $_;
-      # warn "$_ $char";
-    }
-    # I'm going to pick the character to split on that minimises the root
-    # mean square of the number of names in each case. Normally this should
-    # be the one with the most keys, but it may pick a 7 where the 8 has
-    # one long linear search. I'm not sure if RMS or just sum of squares is
-    # actually better.
-    # $max and $min are for the tie-breaker if the root mean squares match.
-    # Assuming that the compiler may be building a jump table for the
-    # switch() then try to minimise the size of that jump table.
-    # Finally use < not <= so that if it still ties the earliest part of
-    # the string wins. Because if that passes but the memEQ fails, it may
-    # only need the start of the string to bin the choice.
-    # I think. But I'm micro-optimising. :-)
-    my $ss;
-    $ss += @$_ * @$_ foreach values %spread;
-    my $rms = sqrt ($ss / keys %spread);
-    if ($rms < $best[0] || ($rms == $best[0] && ($max - $min) < $best[1])) {
-      @best = ($rms, $max - $min, $i, \%spread);
-    }
-  }
-  die "Internal error. Failed to pick a switch point for @names"
-    unless defined $best[2];
-  # use Data::Dumper; print Dumper (@best);
-  my ($offset, $best) = @best[2,3];
-  $body .= $indent . "/* Offset $offset gives the best switch position.  */\n";
-  $body .= $indent . "switch (name[$offset]) {\n";
-  foreach my $char (sort keys %$best) {
-    $body .= $indent . "case '" . C_stringify ($char) . "':\n";
-    foreach my $name (sort @{$best->{$char}}) {
-      my $thisone = $items->{$name};
-      my ($value, $macro, $default, $pre, $post, $def_pre, $def_post)
-        = @$thisone{qw (value macro default pre post def_pre def_post)};
-      $value = $name unless defined $value;
-      $macro = $name unless defined $macro;
-
-      # We have checked this offset.
-      $body .= memEQ_clause ($name, $offset, 2 + length $indent);
-      $body .= return_clause ($value, $thisone->{type},  4 + length $indent,
-                              $macro, $default, $pre, $post,
-                              $def_pre, $def_post);
-      $body .= $indent . "  }\n";
-    }
-    $body .= $indent . "  break;\n";
-  }
-  $body .= $indent . "}\n";
-  return $body;
-}
-
-=item params WHAT
-
-An internal function. I<WHAT> should be a hashref of types the constant
-function will return. I<params> returns a hashref keyed IV NV PV SV to show
-which combination of pointers will be needed in the C argument list.
-
-=cut
-
-sub params {
-  my $what = shift;
-  foreach (sort keys %$what) {
-    warn "ExtUtils::Constant doesn't know how to handle values of type $_" unless defined $XS_Constant{$_};
-  }
-  my $params = {};
-  $params->{IV} = 1 if $what->{IV} || $what->{UV} || $what->{PVN};
-  $params->{NV} = 1 if $what->{NV};
-  $params->{PV} = 1 if $what->{PV} || $what->{PVN};
-  $params->{SV} = 1 if $what->{SV};
-  return $params;
-}
-
-=item dump_names
-
-dump_names DEFAULT_TYPE, TYPES, INDENT, OPTIONS, ITEM...
-
-An internal function to generate the embedded perl code that will regenerate
-the constant subroutines.  I<DEFAULT_TYPE>, I<TYPES> and I<ITEM>s are the
-same as for C_constant.  I<INDENT> is treated as number of spaces to indent
-by.  I<OPTIONS> is a hashref of options. Currently only C<declare_types> is
-recognised.  If the value is true a C<$types> is always declared in the perl
-code generated, if defined and false never declared, and if undefined C<$types>
-is only declared if the values in I<TYPES> as passed in cannot be inferred from
-I<DEFAULT_TYPES> and the I<ITEM>s.
-
-=cut
-
-sub dump_names {
-  my ($default_type, $what, $indent, $options, @items) = @_;
-  my $declare_types = $options->{declare_types};
-  $indent = ' ' x ($indent || 0);
-
-  my $result;
-  my (@simple, @complex, %used_types);
-  foreach (@items) {
-    my $type;
-    if (ref $_) {
-      $type = $_->{type} || $default_type;
-    } else {
-      $_ = {name=>$_};
-      $type = $default_type;
-    }
-    $used_types{$type}++;
-    if ($type eq $default_type and 0 == ($_->{name} =~ tr/A-Za-z0-9_//c)
-        and !defined ($_->{macro}) and !defined ($_->{value})
-        and !defined ($_->{default}) and !defined ($_->{pre})
-        and !defined ($_->{post}) and !defined ($_->{def_pre})
-        and !defined ($_->{def_post})) {
-      # It's the default type, and the name consists only of A-Za-z0-9_
-      push @simple, $_->{name};
-    } else {
-      push @complex, $_;
-    }
-  }
-
-  if (!defined $declare_types) {
-    # Do they pass in any types we weren't already using?
-    foreach (keys %$what) {
-      next if $used_types{$_};
-      $declare_types++; # Found one in $what that wasn't used.
-      last; # And one is enough to terminate this loop
-    }
-  }
-  if ($declare_types) {
-    $result = $indent . 'my $types = {map {($_, 1)} qw('
-      . join (" ", sort keys %$what) . ")};\n";
-  }
-  $result .= wrap ($indent . "my \@names = (qw(",
-		   $indent . "               ", join (" ", sort @simple) . ")");
-  if (@complex) {
-    foreach my $item (sort {$a->{name} cmp $b->{name}} @complex) {
-      my $name = C_stringify $item->{name};
-      my $line = ",\n$indent            {name=>\"$name\"";
-      $line .= ", type=>\"$item->{type}\"" if defined $item->{type};
-      foreach my $thing (qw (macro value default pre post def_pre def_post)) {
-        my $value = $item->{$thing};
-        if (defined $value) {
-          if (ref $value) {
-            $line .= ", $thing=>[\""
-              . join ('", "', map {C_stringify $_} @$value) . '"]';
-          } else {
-            $line .= ", $thing=>\"" . C_stringify($value) . "\"";
-          }
-        }
-      }
-      $line .= "}";
-      # Ensure that the enclosing C comment doesn't end
-      # by turning */  into *" . "/
-      $line =~ s!\*\/!\*" . "/!gs;
-      # gcc -Wall doesn't like finding /* inside a comment
-      $line =~ s!\/\*!/" . "\*!gs;
-      $result .= $line;
-    }
-  }
-  $result .= ");\n";
-
-  $result;
-}
-
-
-=item dogfood
-
-dogfood PACKAGE, SUBNAME, DEFAULT_TYPE, TYPES, INDENT, BREAKOUT, ITEM...
-
-An internal function to generate the embedded perl code that will regenerate
-the constant subroutines.  Parameters are the same as for C_constant.
-
-=cut
-
-sub dogfood {
-  my ($package, $subname, $default_type, $what, $indent, $breakout, @items)
-    = @_;
-  my $result = <<"EOT";
-  /* When generated this function returned values for the list of names given
-     in this section of perl code.  Rather than manually editing these functions
-     to add or remove constants, which would result in this comment and section
-     of code becoming inaccurate, we recommend that you edit this section of
-     code, and use it to regenerate a new set of constant functions which you
-     then use to replace the originals.
-
-     Regenerate these constant functions by feeding this entire source file to
-     perl -x
-
-#!$^X -w
-use ExtUtils::Constant qw (constant_types C_constant XS_constant);
-
-EOT
-  $result .= dump_names ($default_type, $what, 0, {declare_types=>1}, @items);
-  $result .= <<'EOT';
-
-print constant_types(); # macro defs
-EOT
-  $package = C_stringify($package);
-  $result .=
-    "foreach (C_constant (\"$package\", '$subname', '$default_type', \$types, ";
-  # The form of the indent parameter isn't defined. (Yet)
-  if (defined $indent) {
-    require Data::Dumper;
-    $Data::Dumper::Terse=1;
-    $Data::Dumper::Terse=1; # Not used once. :-)
-    chomp ($indent = Data::Dumper::Dumper ($indent));
-    $result .= $indent;
-  } else {
-    $result .= 'undef';
-  }
-  $result .= ", $breakout" . ', @names) ) {
-    print $_, "\n"; # C constant subs
-}
-print "#### XS Section:\n";
-print XS_constant ("' . $package . '", $types);
-__END__
-   */
-
-';
-
-  $result;
+  cluck "ExtUtils::Constant::switch_clause is deprecated";
+  my $indent = shift;
+  my $comment = shift;
+  ExtUtils::Constant::XS->switch_clause({indent=>$indent, comment=>$comment},
+					@_);
 }
 
-=item C_constant
-
-C_constant PACKAGE, SUBNAME, DEFAULT_TYPE, TYPES, INDENT, BREAKOUT, ITEM...
-
-A function that returns a B<list> of C subroutine definitions that return
-the value and type of constants when passed the name by the XS wrapper.
-I<ITEM...> gives a list of constant names. Each can either be a string,
-which is taken as a C macro name, or a reference to a hash with the following
-keys
-
-=over 8
-
-=item name
-
-The name of the constant, as seen by the perl code.
-
-=item type
-
-The type of the constant (I<IV>, I<NV> etc)
-
-=item value
-
-A C expression for the value of the constant, or a list of C expressions if
-the type is aggregate. This defaults to the I<name> if not given.
-
-=item macro
-
-The C pre-processor macro to use in the C<#ifdef>. This defaults to the
-I<name>, and is mainly used if I<value> is an C<enum>. If a reference an
-array is passed then the first element is used in place of the C<#ifdef>
-line, and the second element in place of the C<#endif>. This allows
-pre-processor constructions such as
-
-    #if defined (foo)
-    #if !defined (bar)
-    ...
-    #endif
-    #endif
-
-to be used to determine if a constant is to be defined.
-
-A "macro" 1 signals that the constant is always defined, so the C<#if>/C<#endif>
-test is omitted.
-
-=item default
-
-Default value to use (instead of C<croak>ing with "your vendor has not
-defined...") to return if the macro isn't defined. Specify a reference to
-an array with type followed by value(s).
-
-=item pre
-
-C code to use before the assignment of the value of the constant. This allows
-you to use temporary variables to extract a value from part of a C<struct>
-and return this as I<value>. This C code is places at the start of a block,
-so you can declare variables in it.
-
-=item post
-
-C code to place between the assignment of value (to a temporary) and the
-return from the function. This allows you to clear up anything in I<pre>.
-Rarely needed.
-
-=item def_pre
-=item def_post
-
-Equivalents of I<pre> and I<post> for the default value.
-
-=back
-
-I<PACKAGE> is the name of the package, and is only used in comments inside the
-generated C code.
-
-The next 5 arguments can safely be given as C<undef>, and are mainly used
-for recursion. I<SUBNAME> defaults to C<constant> if undefined.
-
-I<DEFAULT_TYPE> is the type returned by C<ITEM>s that don't specify their
-type. In turn it defaults to I<IV>. I<TYPES> should be given either as a comma
-separated list of types that the C subroutine C<constant> will generate or as
-a reference to a hash. I<DEFAULT_TYPE> will be added to the list if not
-present, as will any types given in the list of I<ITEM>s. The resultant list
-should be the same list of types that C<XS_constant> is given. [Otherwise
-C<XS_constant> and C<C_constant> may differ in the number of parameters to the
-constant function. I<INDENT> is currently unused and ignored. In future it may
-be used to pass in information used to change the C indentation style used.]
-The best way to maintain consistency is to pass in a hash reference and let
-this function update it.
-
-I<BREAKOUT> governs when child functions of I<SUBNAME> are generated.  If there
-are I<BREAKOUT> or more I<ITEM>s with the same length of name, then the code
-to switch between them is placed into a function named I<SUBNAME>_I<LEN>, for
-example C<constant_5> for names 5 characters long.  The default I<BREAKOUT> is
-3.  A single C<ITEM> is always inlined.
-
-=cut
-
-# The parameter now BREAKOUT was previously documented as:
-#
-# I<NAMELEN> if defined signals that all the I<name>s of the I<ITEM>s are of
-# this length, and that the constant name passed in by perl is checked and
-# also of this length. It is used during recursion, and should be C<undef>
-# unless the caller has checked all the lengths during code generation, and
-# the generated subroutine is only to be called with a name of this length.
-#
-# As you can see it now performs this function during recursion by being a
-# scalar reference.
-
 sub C_constant {
   my ($package, $subname, $default_type, $what, $indent, $breakout, @items)
     = @_;
-  $package ||= 'Foo';
-  $subname ||= 'constant';
-  # I'm not using this. But a hashref could be used for full formatting without
-  # breaking this API
-  # $indent ||= 0;
-
-  my ($namelen, $items);
-  if (ref $breakout) {
-    # We are called recursively. We trust @items to be normalised, $what to
-    # be a hashref, and pinch %$items from our parent to save recalculation.
-    ($namelen, $items) = @$breakout;
-  } else {
-    $breakout ||= 3;
-    $default_type ||= 'IV';
-    if (!ref $what) {
-      # Convert line of the form IV,UV,NV to hash
-      $what = {map {$_ => 1} split /,\s*/, ($what || '')};
-      # Figure out what types we're dealing with, and assign all unknowns to the
-      # default type
-    }
-    foreach (@items) {
-      my $name;
-      if (ref $_) {
-        my $orig = $_;
-        # Make a copy which is a normalised version of the ref passed in.
-        $name = $_->{name};
-        my ($type, $macro, $value) = @$_{qw (type macro value)};
-        $type ||= $default_type;
-        $what->{$type} = 1;
-        $_ = {name=>$name, type=>$type};
-
-        undef $macro if defined $macro and $macro eq $name;
-        $_->{macro} = $macro if defined $macro;
-        undef $value if defined $value and $value eq $name;
-        $_->{value} = $value if defined $value;
-        foreach my $key (qw(default pre post def_pre def_post)) {
-          my $value = $orig->{$key};
-          $_->{$key} = $value if defined $value;
-          # warn "$key $value";
-        }
-      } else {
-        $name = $_;
-        $_ = {name=>$_, type=>$default_type};
-        $what->{$default_type} = 1;
-      }
-      warn "ExtUtils::Constant doesn't know how to handle values of type $_ used in macro $name" unless defined $XS_Constant{$_->{type}};
-      if (exists $items->{$name}) {
-        die "Multiple definitions for macro $name";
-      }
-      $items->{$name} = $_;
-    }
-  }
-  my $params = params ($what);
-
-  my ($body, @subs) = "static int\n$subname (pTHX_ const char *name";
-  $body .= ", STRLEN len" unless defined $namelen;
-  $body .= ", IV *iv_return" if $params->{IV};
-  $body .= ", NV *nv_return" if $params->{NV};
-  $body .= ", const char **pv_return" if $params->{PV};
-  $body .= ", SV **sv_return" if $params->{SV};
-  $body .= ") {\n";
-
-  if (defined $namelen) {
-    # We are a child subroutine. Print the simple description
-    my $comment = 'When generated this function returned values for the list'
-      . ' of names given here.  However, subsequent manual editing may have'
-        . ' added or removed some.';
-    $body .= switch_clause (2, $comment, $namelen, $items, @items);
-  } else {
-    # We are the top level.
-    $body .= "  /* Initially switch on the length of the name.  */\n";
-    $body .= dogfood ($package, $subname, $default_type, $what, $indent,
-                      $breakout, @items);
-    $body .= "  switch (len) {\n";
-    # Need to group names of the same length
-    my @by_length;
-    foreach (@items) {
-      push @{$by_length[length $_->{name}]}, $_;
-    }
-    foreach my $i (0 .. $#by_length) {
-      next unless $by_length[$i];	# None of this length
-      $body .= "  case $i:\n";
-      if (@{$by_length[$i]} == 1) {
-        my $thisone = $by_length[$i]->[0];
-        my ($name, $value, $macro, $default, $pre, $post, $def_pre, $def_post)
-          = @$thisone{qw (name value macro default pre post def_pre def_post)};
-        $value = $name unless defined $value;
-        $macro = $name unless defined $macro;
-
-        $body .= memEQ_clause ($name);
-        $body .= return_clause ($value, $thisone->{type}, undef, $macro,
-                                $default, $pre, $post, $def_pre, $def_post);
-        $body .= "    }\n";
-      } elsif (@{$by_length[$i]} < $breakout) {
-        $body .= switch_clause (4, '', $i, $items, @{$by_length[$i]});
-      } else {
-        # Only use the minimal set of parameters actually needed by the types
-        # of the names of this length.
-        my $what = {};
-        foreach (@{$by_length[$i]}) {
-          $what->{$_->{type}} = 1;
-        }
-        $params = params ($what);
-        push @subs, C_constant ($package, "${subname}_$i", $default_type, $what,
-                                $indent, [$i, $items], @{$by_length[$i]});
-        $body .= "    return ${subname}_$i (aTHX_ name";
-        $body .= ", iv_return" if $params->{IV};
-        $body .= ", nv_return" if $params->{NV};
-        $body .= ", pv_return" if $params->{PV};
-        $body .= ", sv_return" if $params->{SV};
-        $body .= ");\n";
-      }
-      $body .= "    break;\n";
-    }
-    $body .= "  }\n";
-  }
-  $body .= "  return PERL_constant_NOTFOUND;\n}\n";
-  return (@subs, $body);
+  ExtUtils::Constant::XS->C_constant({package => $package, subname => $subname,
+				      default_type => $default_type,
+				      types => $what, indent => $indent,
+				      breakout => $breakout}, @items);
 }
 
 =item XS_constant PACKAGE, TYPES, SUBNAME, C_SUBNAME
@@ -853,7 +163,7 @@ be the same list of types as C<C_constant> was given.
 the number of parameters passed to the C function C<constant>]
 
 You can call the perl visible subroutine something other than C<constant> if
-you give the parameter I<SUBNAME>. The C subroutine it calls defaults to the
+you give the parameter I<SUBNAME>. The C subroutine it calls defaults to
 the name of the perl visible subroutine, unless you give the parameter
 I<C_SUBNAME>.
 
@@ -871,7 +181,7 @@ sub XS_constant {
     # Convert line of the form IV,UV,NV to hash
     $what = {map {$_ => 1} split /,\s*/, ($what)};
   }
-  my $params = params ($what);
+  my $params = ExtUtils::Constant::XS->params ($what);
   my $type;
 
   my $xs = <<"EOT";
@@ -908,6 +218,14 @@ EOT
     INPUT:
 	SV *		sv;
         const char *	s = SvPV(sv, len);
+EOT
+  if ($params->{''}) {
+  $xs .= << 'EOT';
+    INPUT:
+	int		utf8 = SvUTF8(sv);
+EOT
+  }
+  $xs .= << 'EOT';
     PPCODE:
 EOT
 
@@ -918,28 +236,37 @@ EOT
 EOT
   }
   $xs .= "	type = $C_subname(aTHX_ s, len";
+  $xs .= ', utf8' if $params->{''};
   $xs .= ', &iv' if $params->{IV};
   $xs .= ', &nv' if $params->{NV};
   $xs .= ', &pv' if $params->{PV};
   $xs .= ', &sv' if $params->{SV};
   $xs .= ");\n";
 
+  # If anyone is insane enough to suggest a package name containing %
+  my $package_sprintf_safe = $package;
+  $package_sprintf_safe =~ s/%/%%/g;
+
   $xs .= << "EOT";
       /* Return 1 or 2 items. First is error message, or undef if no error.
            Second, if present, is found value */
         switch (type) {
         case PERL_constant_NOTFOUND:
-          sv = sv_2mortal(newSVpvf("%s is not a valid $package macro", s));
+          sv =
+	    sv_2mortal(newSVpvf("%s is not a valid $package_sprintf_safe macro", s));
           PUSHs(sv);
           break;
         case PERL_constant_NOTDEF:
           sv = sv_2mortal(newSVpvf(
-	    "Your vendor has not defined $package macro %s, used", s));
+	    "Your vendor has not defined $package_sprintf_safe macro %s, used",
+				   s));
           PUSHs(sv);
           break;
 EOT
 
   foreach $type (sort keys %XS_Constant) {
+    # '' marks utf8 flag needed.
+    next if $type eq '';
     $xs .= "\t/* Uncomment this if you need to return ${type}s\n"
       unless $what->{$type};
     $xs .= "        case PERL_constant_IS$type:\n";
@@ -962,7 +289,7 @@ EOT
   $xs .= << "EOT";
         default:
           sv = sv_2mortal(newSVpvf(
-	    "Unexpected return type %d while processing $package macro %s, used",
+	    "Unexpected return type %d while processing $package_sprintf_safe macro %s, used",
                type, s));
           PUSHs(sv);
         }
@@ -1047,7 +374,7 @@ END
 
 WriteMakefileSnippet ATTRIBUTE =E<gt> VALUE [, ...] 
 
-An function to generate perl code for Makefile.PL that will regenerate
+A function to generate perl code for Makefile.PL that will regenerate
 the constant subroutines.  Parameters are named as passed to C<WriteConstants>,
 with the addition of C<INDENT> to specify the number of leading spaces
 (default 2).
@@ -1077,16 +404,17 @@ EOT
 EOT
 
   $result =~ s/^/' 'x$indent/gem;
-  return dump_names ($args{DEFAULT_TYPE}, undef, $indent, undef,
-                           @{$args{NAMES}})
-          . $result;
+  return ExtUtils::Constant::XS->dump_names({default_type=>$args{DEFAULT_TYPE},
+					     indent=>$indent,},
+					    @{$args{NAMES}})
+    . $result;
 }
 
 =item WriteConstants ATTRIBUTE =E<gt> VALUE [, ...]
 
 Writes a file of C code and a file of XS code which you should C<#include>
 and C<INCLUDE> in the C and XS sections respectively of your module's XS
-code.  You probaby want to do this in your C<Makefile.PL>, so that you can
+code.  You probably want to do this in your C<Makefile.PL>, so that you can
 easily edit the list of constants without touching the rest of your module.
 The attributes supported are
 
@@ -1110,15 +438,32 @@ for each group with this number or more names in.
 An array of constants' names, either scalars containing names, or hashrefs
 as detailed in L<"C_constant">.
 
+=item PROXYSUBS
+
+If true, uses proxy subs. See L<ExtUtils::Constant::ProxySubs>.
+
+=item C_FH
+
+A filehandle to write the C code to.  If not given, then I<C_FILE> is opened
+for writing.
+
 =item C_FILE
 
 The name of the file to write containing the C code.  The default is
-C<constants.c>.
+C<const-c.inc>.  The C<-> in the name ensures that the file can't be
+mistaken for anything related to a legitimate perl package name, and
+not naming the file C<.c> avoids having to override Makefile.PL's
+C<.xs> to C<.c> rules.
+
+=item XS_FH
+
+A filehandle to write the XS code to.  If not given, then I<XS_FILE> is opened
+for writing.
 
 =item XS_FILE
 
 The name of the file to write containing the XS code.  The default is
-C<constants.xs>.
+C<const-xs.inc>.
 
 =item SUBNAME
 
@@ -1139,8 +484,8 @@ C<constant_10> with the default I<XS_SUBNAME>.
 sub WriteConstants {
   my %ARGS =
     ( # defaults
-     C_FILE =>       'constants.c',
-     XS_FILE =>      'constants.xs',
+     C_FILE =>       'const-c.inc',
+     XS_FILE =>      'const-xs.inc',
      SUBNAME =>      'constant',
      DEFAULT_TYPE => 'IV',
      @_);
@@ -1149,27 +494,62 @@ sub WriteConstants {
 
   croak "Module name not specified" unless length $ARGS{NAME};
 
-  open my $c_fh, ">$ARGS{C_FILE}" or die "Can't open $ARGS{C_FILE}: $!";
-  open my $xs_fh, ">$ARGS{XS_FILE}" or die "Can't open $ARGS{XS_FILE}: $!";
+  my $c_fh = $ARGS{C_FH};
+  if (!$c_fh) {
+      if ($] <= 5.008) {
+	  # We need these little games, rather than doing things
+	  # unconditionally, because we're used in core Makefile.PLs before
+	  # IO is available (needed by filehandle), but also we want to work on
+	  # older perls where undefined scalars do not automatically turn into
+	  # anonymous file handles.
+	  require FileHandle;
+	  $c_fh = FileHandle->new();
+      }
+      open $c_fh, ">$ARGS{C_FILE}" or die "Can't open $ARGS{C_FILE}: $!";
+  }
+
+  my $xs_fh = $ARGS{XS_FH};
+  if (!$xs_fh) {
+      if ($] <= 5.008) {
+	  require FileHandle;
+	  $xs_fh = FileHandle->new();
+      }
+      open $xs_fh, ">$ARGS{XS_FILE}" or die "Can't open $ARGS{XS_FILE}: $!";
+  }
 
   # As this subroutine is intended to make code that isn't edited, there's no
   # need for the user to specify any types that aren't found in the list of
   # names.
-  my $types = {};
-
-  print $c_fh constant_types(); # macro defs
-  print $c_fh "\n";
-
-  # indent is still undef. Until anyone implents indent style rules with it.
-  foreach (C_constant ($ARGS{NAME}, $ARGS{C_SUBNAME}, $ARGS{DEFAULT_TYPE},
-                       $types, undef, $ARGS{BREAKOUT_AT}, @{$ARGS{NAMES}})) {
-    print $c_fh $_, "\n"; # C constant subs
+  
+  if ($ARGS{PROXYSUBS}) {
+      require ExtUtils::Constant::ProxySubs;
+      $ARGS{C_FH} = $c_fh;
+      $ARGS{XS_FH} = $xs_fh;
+      ExtUtils::Constant::ProxySubs->WriteConstants(%ARGS);
+  } else {
+      my $types = {};
+
+      print $c_fh constant_types(); # macro defs
+      print $c_fh "\n";
+
+      # indent is still undef. Until anyone implements indent style rules with
+      # it.
+      foreach (ExtUtils::Constant::XS->C_constant({package => $ARGS{NAME},
+						   subname => $ARGS{C_SUBNAME},
+						   default_type =>
+						       $ARGS{DEFAULT_TYPE},
+						       types => $types,
+						       breakout =>
+						       $ARGS{BREAKOUT_AT}},
+						  @{$ARGS{NAMES}})) {
+	  print $c_fh $_, "\n"; # C constant subs
+      }
+      print $xs_fh XS_constant ($ARGS{NAME}, $types, $ARGS{XS_SUBNAME},
+				$ARGS{C_SUBNAME});
   }
-  print $xs_fh XS_constant ($ARGS{NAME}, $types, $ARGS{XS_SUBNAME},
-                            $ARGS{C_SUBNAME});
 
-  close $c_fh or warn "Error closing $ARGS{C_FILE}: $!";
-  close $xs_fh or warn "Error closing $ARGS{XS_FILE}: $!";
+  close $c_fh or warn "Error closing $ARGS{C_FILE}: $!" unless $ARGS{C_FH};
+  close $xs_fh or warn "Error closing $ARGS{XS_FILE}: $!" unless $ARGS{XS_FH};
 }
 
 1;