X-Git-Url: http://git.shadowcat.co.uk/gitweb/gitweb.cgi?a=blobdiff_plain;f=lib%2Fopen.pm;h=3d7782fc8b5b41dc4131978d57f9f038ff78a1ac;hb=149e698571d538389632b17001d47e502cc5be50;hp=c90181bb1b6afae9f76abda93cf416823b3e2726;hpb=d151aa0ec14d76b1fc090f7a4c70252742dc3539;p=p5sagit%2Fp5-mst-13.2.git

diff --git a/lib/open.pm b/lib/open.pm
index c90181b..3d7782f 100644
--- a/lib/open.pm
+++ b/lib/open.pm
@@ -2,43 +2,95 @@ package open;
 use Carp;
 $open::hint_bits = 0x20000;
 
-# layers array and hash mainly manipulated by C code in perlio.c
-use vars qw(%layers @layers);
+our $VERSION = '1.01';
 
-# Populate hash in non-PerlIO case
-%layers = (crlf => 1, raw => 0) unless (@layers);
+my $locale_encoding;
 
-# warn join(',',keys %layers);
+sub in_locale { $^H & $locale::hint_bits }
 
-our $VERSION = '1.00';
+sub _get_locale_encoding {
+    unless (defined $locale_encoding) {
+	eval {
+	    # I18N::Langinfo isn't available everywhere
+	    require I18N::Langinfo;
+	    I18N::Langinfo->import('langinfo', 'CODESET');
+	};
+	unless ($@) {
+	    $locale_encoding = langinfo(CODESET());
+	}
+	my $country_language;
+        if (not $locale_encoding && in_locale()) {
+	    if ($ENV{LC_ALL} =~ /^([^.]+)\.([^.]+)$/) {
+		($country_language, $locale_encoding) = ($1, $2);
+	    } elsif ($ENV{LANG} =~ /^([^.]+)\.([^.]+)$/) {
+		($country_language, $locale_encoding) = ($1, $2);
+	    }
+	} else {
+	    # Could do heuristics based on the country and language
+	    # parts of LC_ALL and LANG (the parts before the dot (if any)),
+	    # since we have Locale::Country and Locale::Language available.
+	    # TODO: get a database of Language -> Encoding mappings
+	    # (the Estonian database at http://www.eki.ee/letter/
+	    # would be excellent!) --jhi
+	}
+	if (defined $locale_encoding &&
+	    $locale_encoding eq 'euc' &&
+	    defined $country_language) {
+	    if ($country_language =~ /^ja_JP|japan(?:ese)?$/i) {
+		$locale_encoding = 'eucjp';
+	    } elsif ($country_language =~ /^ko_KR|korean?$/i) {
+		$locale_encoding = 'euckr';
+	    } elsif ($country_language =~ /^zh_TW|taiwan(?:ese)?$/i) {
+		$locale_encoding = 'euctw';
+	    }
+	    croak "Locale encoding 'euc' too ambiguous"
+		if $locale_encoding eq 'euc';
+	}
+    }
+}
 
 sub import {
     my ($class,@args) = @_;
     croak("`use open' needs explicit list of disciplines") unless @args;
     $^H |= $open::hint_bits;
-    my ($in,$out) = split(/\0/,(${^OPEN} || '\0'));
-    my @in  = split(/\s+/,$in);
-    my @out = split(/\s+/,$out);
+    my ($in,$out) = split(/\0/,(${^OPEN} || "\0"), -1);
     while (@args) {
 	my $type = shift(@args);
 	my $discp = shift(@args);
 	my @val;
 	foreach my $layer (split(/\s+/,$discp)) {
             $layer =~ s/^://;
-	    unless(exists $layers{$layer}) {
-		carp("Unknown discipline layer '$layer'");
+	    if ($layer eq 'locale') {
+		use Encode;
+		_get_locale_encoding()
+		    unless defined $locale_encoding;
+		croak "Cannot figure out an encoding to use"
+		    unless defined $locale_encoding;
+		if ($locale_encoding =~ /^utf-?8$/i) {
+		    $layer = "utf8";
+		} else {
+		    $layer = "encoding($locale_encoding)";
+		}
+	    } else {
+		unless(PerlIO::Layer::->find($layer)) {
+		    carp("Unknown discipline layer '$layer'");
+		}
 	    }
 	    push(@val,":$layer");
 	    if ($layer =~ /^(crlf|raw)$/) {
 		$^H{"open_$type"} = $layer;
 	    }
 	}
+	# print "# type = $type, val = @val\n";
 	if ($type eq 'IN') {
 	    $in  = join(' ',@val);
 	}
 	elsif ($type eq 'OUT') {
 	    $out = join(' ',@val);
 	}
+	elsif ($type eq 'INOUT') {
+	    $in = $out = join(' ',@val);
+	}
 	else {
 	    croak "Unknown discipline class '$type'";
 	}
@@ -56,6 +108,7 @@ open - perl pragma to set default disciplines for input and output
 =head1 SYNOPSIS
 
     use open IN => ":crlf", OUT => ":raw";
+    use open INOUT => ":utf8";
 
 =head1 DESCRIPTION
 
@@ -90,33 +143,16 @@ everywhere if PerlIO is enabled.
 
 =head1 IMPLEMENTATION DETAILS
 
-There are two package variables C<%layers> and C<@layers> which are
-mainly manipulated by C code in F<perlio.c>, but are visible to the
-nosy:
-
-  print "Have ",join(',',keys %open::layers),"\n";
-  print "Using ",join(',',@open::layers),"\n";
-
-The C<%open::layers> hash is a record of the available "layers" that
-may be pushed onto a C<PerlIO> stream. The values of the hash are Perl
-objects, of class C<PerlIO::Layer> which are created by the C code in
-F<perlio.c>.  As yet there is nothing useful you can do with the
-objects at the perl level.
-
-The C<@open::layers> array is the current set of layers and their
-arguments.  The array consists of layer => argument pairs and I<must>
-always have even number of entries and the even entries I<must> be
-C<PerlIO::Layer> objects or Perl will "die" when it attempts to open a
-filehandle. In most cases the odd entry will be C<undef>, but in the
-case of (say) ":encoding(iso-8859-1)" it will be 'iso-8859-1'. These
-argument entries are currently restricted to being strings.
-
-When a new C<PerlIO> stream is opened, the C code looks at the array
-to determine the default layers to be pushed. So with care it is
-possible to manipulate the default layer "stack":
-
-    splice(@PerlIO::layers,-2,2);
-    push(@PerlIO::layers,$PerlIO::layers{'stdio'} => undef);
+There is a class method in C<PerlIO::Layer> C<find> which is
+implemented as XS code.  It is called by C<import> to validate the
+layers:
+
+   PerlIO::Layer::->find("perlio")
+
+The return value (if defined) is a Perl object, of class
+C<PerlIO::Layer> which is created by the C code in F<perlio.c>.  As
+yet there is nothing useful you can do with the object at the perl
+level.
 
 =head1 SEE ALSO