# Copyright (C) 2001, 2003, 2004, 2006 Free Software Foundation, Inc. # This program is free software: you can redistribute it and/or modify # it under the terms of the GNU General Public License as published by # the Free Software Foundation, either version 3 of the License, or # (at your option) any later version. # This program is distributed in the hope that it will be useful, # but WITHOUT ANY WARRANTY; without even the implied warranty of # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # GNU General Public License for more details. # You should have received a copy of the GNU General Public License # along with this program. If not, see . # Written by Akim Demaille . ############################################################### # The main copy of this file is in Automake's CVS repository. # # Updates should be sent to automake-patches@gnu.org. # ############################################################### package Autom4te::XFile; =head1 NAME Autom4te::XFile - supply object methods for filehandles with error handling =head1 SYNOPSIS use Autom4te::XFile; $fh = new Autom4te::XFile; $fh->open ("< file"); # No need to check $FH: we died if open failed. print <$fh>; $fh->close; # No need to check the return value of close: we died if it failed. $fh = new Autom4te::XFile "> file"; # No need to check $FH: we died if new failed. print $fh "bar\n"; $fh->close; $fh = new Autom4te::XFile "file", "r"; # No need to check $FH: we died if new failed. defined $fh print <$fh>; undef $fh; # automatically closes the file and checks for errors. $fh = new Autom4te::XFile "file", O_WRONLY | O_APPEND; # No need to check $FH: we died if new failed. print $fh "corge\n"; $pos = $fh->getpos; $fh->setpos ($pos); undef $fh; # automatically closes the file and checks for errors. autoflush STDOUT 1; =head1 DESCRIPTION C inherits from C. It provides the method C returning the file name. It provides dying version of the methods C, C (corresponding to C), C, C, C, and C. It also overrides the C and C methods to translate C<\r\n> to C<\n>. =head1 SEE ALSO L, L, L L L =head1 HISTORY Derived from IO::File.pm by Akim Demaille EFE. =cut require 5.000; use strict; use vars qw($VERSION @EXPORT @EXPORT_OK $AUTOLOAD @ISA); use Carp; use Errno; use IO::File; use File::Basename; use Autom4te::ChannelDefs; use Autom4te::Channels qw(msg); use Autom4te::FileUtils; require Exporter; require DynaLoader; @ISA = qw(IO::File Exporter DynaLoader); $VERSION = "1.2"; @EXPORT = @IO::File::EXPORT; eval { # Make all Fcntl O_XXX and LOCK_XXX constants available for importing require Fcntl; my @O = grep /^(LOCK|O)_/, @Fcntl::EXPORT, @Fcntl::EXPORT_OK; Fcntl->import (@O); # first we import what we want to export push (@EXPORT, @O); }; # Used in croak error messages. my $me = basename ($0); ################################################ ## Constructor ## sub new { my $type = shift; my $class = ref $type || $type || "Autom4te::XFile"; my $fh = $class->SUPER::new (); if (@_) { $fh->open (@_); } $fh; } ################################################ ## Open ## sub open { my $fh = shift; my ($file) = @_; # WARNING: Gross hack: $FH is a typeglob: use its hash slot to store # the `name' of the file we are opening. See the example with # io_socket_timeout in IO::Socket for more, and read Graham's # comment in IO::Handle. ${*$fh}{'autom4te_xfile_file'} = "$file"; if (!$fh->SUPER::open (@_)) { fatal "cannot open $file: $!"; } # In case we're running under MSWindows, don't write with CRLF. # (This circumvents a bug in at least Cygwin bash where the shell # parsing fails on lines ending with the continuation character '\' # and CRLF). binmode $fh if $file =~ /^\s*>/; } ################################################ ## Close ## sub close { my $fh = shift; if (!$fh->SUPER::close (@_)) { my $file = $fh->name; Autom4te::FileUtils::handle_exec_errors $file unless $!; fatal "cannot close $file: $!"; } } ################################################ ## Getline ## # Some Win32/perl installations fail to translate \r\n to \n on input # so we do that here. sub getline { local $_ = $_[0]->SUPER::getline; # Perform a _global_ replacement: $_ may can contains many lines # in slurp mode ($/ = undef). s/\015\012/\n/gs if defined $_; return $_; } ################################################ ## Getlines ## sub getlines { my @res = (); my $line; push @res, $line while $line = $_[0]->getline; return @res; } ################################################ ## Name ## sub name { my $fh = shift; return ${*$fh}{'autom4te_xfile_file'}; } ################################################ ## Lock ## sub lock { my ($fh, $mode) = @_; # Cannot use @_ here. # Unless explicitly configured otherwise, Perl implements its `flock' with the # first of flock(2), fcntl(2), or lockf(3) that works. These can fail on # NFS-backed files, with ENOLCK (GNU/Linux) or EOPNOTSUPP (FreeBSD); we # usually ignore these errors. If $ENV{MAKEFLAGS} suggests that a parallel # invocation of GNU `make' has invoked the tool we serve, report all locking # failures and abort. # # On Unicos, flock(2) and fcntl(2) over NFS hang indefinitely when `lockd' is # not running. NetBSD NFS clients silently grant all locks. We do not # attempt to defend against these dangers. if (!flock ($fh, $mode)) { my $make_j = (exists $ENV{'MAKEFLAGS'} && " -$ENV{'MAKEFLAGS'}" =~ / (-[BdeikrRsSw]*j|---?jobs)/); my $note = "\nforgo `make -j' or use a file system that supports locks"; my $file = $fh->name; msg ($make_j ? 'fatal' : 'unsupported', "cannot lock $file with mode $mode: $!" . ($make_j ? $note : "")) if $make_j || !($!{ENOLCK} || $!{EOPNOTSUPP}); } } ################################################ ## Seek ## sub seek { my $fh = shift; # Cannot use @_ here. if (!seek ($fh, $_[0], $_[1])) { my $file = $fh->name; fatal "$me: cannot rewind $file with @_: $!"; } } ################################################ ## Truncate ## sub truncate { my ($fh, $len) = @_; if (!truncate ($fh, $len)) { my $file = $fh->name; fatal "cannot truncate $file at $len: $!"; } } 1; ### Setup "GNU" style for perl-mode and cperl-mode. ## Local Variables: ## perl-indent-level: 2 ## perl-continued-statement-offset: 2 ## perl-continued-brace-offset: 0 ## perl-brace-offset: 0 ## perl-brace-imaginary-offset: 0 ## perl-label-offset: -2 ## cperl-indent-level: 2 ## cperl-brace-offset: 0 ## cperl-continued-brace-offset: 0 ## cperl-label-offset: -2 ## cperl-extra-newline-before-brace: t ## cperl-merge-trailing-else: nil ## cperl-continued-statement-offset: 2 ## End: