View file File name : locale.pm Content :package locale; our $VERSION = '1.09'; use Config; $Carp::Internal{ (__PACKAGE__) } = 1; =head1 NAME locale - Perl pragma to use or avoid POSIX locales for built-in operations =head1 WARNING DO NOT USE this pragma in scripts that have multiple L<threads|threads> active. The locale is not local to a single thread. Another thread may change the locale at any time, which could cause at a minimum that a given thread is operating in a locale it isn't expecting to be in. On some platforms, segfaults can also occur. The locale change need not be explicit; some operations cause perl to change the locale itself. You are vulnerable simply by having done a C<"use locale">. =head1 SYNOPSIS @x = sort @y; # Native-platform/Unicode code point sort order { use locale; @x = sort @y; # Locale-defined sort order } @x = sort @y; # Native-platform/Unicode code point sort order # again =head1 DESCRIPTION This pragma tells the compiler to enable (or disable) the use of POSIX locales for built-in operations (for example, LC_CTYPE for regular expressions, LC_COLLATE for string comparison, and LC_NUMERIC for number formatting). Each "use locale" or "no locale" affects statements to the end of the enclosing BLOCK. See L<perllocale> for more detailed information on how Perl supports locales. On systems that don't have locales, this pragma will cause your operations to behave as if in the "C" locale; attempts to change the locale will fail. =cut # A separate bit is used for each of the two forms of the pragma, to save # having to look at %^H for the normal case of a plain 'use locale' without an # argument. $locale::hint_bits = 0x4; $locale::partial_hint_bits = 0x10; # If pragma has an argument # The pseudo-category :characters consists of 2 real ones; but it also is # given its own number, -1, because in the complement form it also has the # side effect of "use feature 'unicode_strings'" sub import { shift; # should be 'locale'; not checked $^H{locale} = 0 unless defined $^H{locale}; if (! @_) { # If no parameter, use the plain form that changes all categories $^H |= $locale::hint_bits; } else { my @categories = ( qw(:ctype :collate :messages :numeric :monetary :time) ); for (my $i = 0; $i < @_; $i++) { my $arg = $_[$i]; $complement = $arg =~ s/ : ( ! | not_ ) /:/x; if (! grep { $arg eq $_ } @categories, ":characters") { require Carp; Carp::croak("Unknown parameter '$_[$i]' to 'use locale'"); } if ($complement) { if ($i != 0 || $i < @_ - 1) { require Carp; Carp::croak("Only one argument to 'use locale' allowed" . "if is $complement"); } if ($arg eq ':characters') { push @_, grep { $_ ne ':ctype' && $_ ne ':collate' } @categories; # We add 1 to the category number; This category number # is -1 $^H{locale} |= (1 << 0); } else { push @_, grep { $_ ne $arg } @categories; } next; } elsif ($arg eq ':characters') { push @_, ':ctype', ':collate'; next; } $^H |= $locale::partial_hint_bits; # This form of the pragma overrides the other $^H &= ~$locale::hint_bits; $arg =~ s/^://; eval { require POSIX; import POSIX 'locale_h'; }; # Map our names to the ones defined by POSIX my $LC = "LC_" . uc($arg); my $bit = eval "&POSIX::$LC"; if (defined $bit) { # XXX Should we warn that this category isn't # supported on this platform, or make it # always be the C locale? # Verify our assumption. if (! ($bit >= 0 && $bit < 31)) { require Carp; Carp::croak("Cannot have ':$arg' parameter to 'use locale'" . " on this platform. Use the 'perlbug' utility" . " to report this problem, or send email to" . " 'perlbug\@perl.org'. $LC=$bit"); } # 1 is added so that the pseudo-category :characters, which is # -1, comes out 0. $^H{locale} |= 1 << ($bit + 1); } } } } sub unimport { $^H &= ~($locale::hint_bits|$locale::partial_hint_bits); $^H{locale} = 0; } 1;