X-Git-Url: http://git.annexia.org/?a=blobdiff_plain;f=tools%2Fvirt-edit;h=c1556eb982890f4eebffe7eeed30cab8c47f07a9;hb=439a42efdb052748c8457f866b2c68a581034826;hp=d4e11dbfa3a58f7c6167247eb780fdf457a19a58;hpb=8f6d8b05152fda68e0c01848c0e5239e0093548a;p=libguestfs.git diff --git a/tools/virt-edit b/tools/virt-edit index d4e11db..c1556eb 100755 --- a/tools/virt-edit +++ b/tools/virt-edit @@ -1,6 +1,6 @@ #!/usr/bin/perl -w # virt-edit -# Copyright (C) 2009-2010 Red Hat Inc. +# Copyright (C) 2009-2011 Red Hat 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 @@ -20,12 +20,11 @@ use warnings; use strict; use Sys::Guestfs; -use Sys::Guestfs::Lib qw(open_guest get_partitions resolve_windows_path - inspect_all_partitions inspect_partition - inspect_operating_systems mount_operating_system); +use Sys::Guestfs::Lib qw(open_guest); use Pod::Usage; use Getopt::Long; use File::Temp qw/tempfile/; +use File::Basename; use Locale::TextDomain 'libguestfs'; =encoding utf8 @@ -53,8 +52,13 @@ you from doing this, but doesn't catch all cases. C is a command line tool to edit C where C exists in the named virtual machine (or disk image). -If you want to just view a file, use L. For more complex -cases you should look at the L tool. +If you want to just view a file, use L. + +For more complex cases you should look at the L tool +(see L below). + +C cannot be used to create a new file, nor to edit +multiple files. L can do that and much more. =head1 EXAMPLES @@ -64,6 +68,10 @@ Edit the named files interactively: virt-edit mydomain /etc/passwd +For Windows guests, some Windows paths are understood: + + virt-edit mywindomain 'c:\autoexec.bat' + You can also edit files non-interactively (see L below). To change the init default level to 5: @@ -92,6 +100,22 @@ Display version number and exit. =cut +my $backup; + +=item B<--backup extension> | B<-b extension> + +Create a backup of the original file I. +The backup has the original filename with C added. + +Usually the first character of C would be a dot C<.> +so you would write: + + virt-edit -b .orig [etc] + +By default, no backup file is made. + +=cut + my $uri; =item B<--connect URI> | B<-c URI> @@ -104,6 +128,23 @@ at all. =cut +my $format; + +=item B<--format> raw + +Specify the format of disk images given on the command line. If this +is omitted then the format is autodetected from the content of the +disk image. + +If disk images are requested from libvirt, then this program asks +libvirt for this information. In this case, the value of the format +parameter is ignored. + +If working with untrusted raw-format guest disk images, you should +ensure the format is always specified. + +=cut + my $expr; =item B<--expr EXPR> | B<-e EXPR> @@ -122,7 +163,9 @@ being altered by the shell. GetOptions ("help|?" => \$help, "version" => \$version, "connect|c=s" => \$uri, + "format=s" => \$format, "expr|e=s" => \$expr, + "backup|b=s" => \$backup, ) or pod2usage (2); pod2usage (1) if $help; if ($version) { @@ -139,34 +182,40 @@ my $filename = pop @ARGV; my $g; if ($uri) { - $g = open_guest (\@ARGV, address => $uri, rw => 1); + $g = open_guest (\@ARGV, address => $uri, rw => 1, format => $format); } else { - $g = open_guest (\@ARGV, rw => 1); + $g = open_guest (\@ARGV, rw => 1, format => $format); } $g->launch (); -# List of possible filesystems. -my @partitions = get_partitions ($g); - -# Now query each one to build up a picture of what's in it. -my %fses = - inspect_all_partitions ($g, \@partitions, - use_windows_registry => 0); - -my $oses = inspect_operating_systems ($g, \%fses); - -my @roots = keys %$oses; -die __"multiboot operating systems are not supported by virt-edit" if @roots > 1; -my $root_dev = $roots[0]; +my @roots = $g->inspect_os (); +if (@roots == 0) { + die __x("{prog}: No operating system could be detected inside this disk image.\n\nThis may be because the file is not a disk image, or is not a virtual machine\nimage, or because the OS type is not understood by libguestfs.\n\nIf you feel this is an error, please file a bug report including as much\ninformation about the disk image as possible.\n", + prog => basename ($0)); +} +if (@roots > 1) { + die __x("{prog}: multiboot operating systems are not supported.\n", + prog => basename ($0)) +} +my $root = $roots[0]; +my %fses = $g->inspect_get_mountpoints ($root); +my @fses = sort { length $a <=> length $b } keys %fses; +foreach (@fses) { + $g->mount_options ("", $fses{$_}, $_); +} -my $os = $oses->{$root_dev}; -mount_operating_system ($g, $os, 0); +# Special handling for Windows filenames. +$filename = windows_path ($g, $root, $filename) + if $g->inspect_get_type ($root) eq "windows"; -my ($fh_not_used, $tempname) = tempfile (); +my ($fh, $tempname) = tempfile (UNLINK => 1); +my $fddev = "/dev/fd/" . fileno ($fh); # Allow this to fail in case eg. the file does not exist. -$g->download($filename, $tempname); +$g->download ($filename, $fddev); + +close $fh or die "close: $!"; my $do_upload = $tempname; @@ -186,7 +235,7 @@ if (!defined $expr) { print __"File not changed.\n"; } } else { - my ($fh, $tempout) = tempfile (); + my ($fh, $tempout) = tempfile (UNLINK => 1); # Apply a Perl expression to the lines of the file. open IFILE, $tempname or die "$tempname: $!"; @@ -197,21 +246,37 @@ if (!defined $expr) { die if $@; print $fh $_ or die "print: $!"; } - close $fh; + close $fh or die "close: $!"; $do_upload = $tempout; } if (defined $do_upload) { - $g->upload ($do_upload, $filename); + # Upload to a new file, so if it fails we don't end up with + # a partially written file. Give the new file a completely + # random name so we have only a tiny chance of overwriting + # some existing file. + my $dirname = $filename; + $dirname =~ s{/[^/]+$}{/}; + + my @chars = ('a'..'z', 'A'..'Z', '0'..'9'); + my $newname = $dirname; + foreach (0..7) { + $newname .= $chars[rand @chars]; + } + + $g->upload ($do_upload, $newname); + + # Backup or overwrite? + $g->mv ($filename, "$filename$backup") if defined $backup; + $g->mv ($newname, $filename); + $g->umount_all (); $g->sync (); } undef $g; -exit 0; - =head1 NON-INTERACTIVE EDITING C normally calls out to C<$EDITOR> (or vi) so @@ -274,6 +339,140 @@ file): my $m = $_; chomp $m; $m =~ /some text$/ +=head1 WINDOWS PATHS + +C has a limited ability to understand Windows drive letters +and paths (eg. C). + +If and only if the guest is running Windows then: + +=over 4 + +=item * + +Drive letter prefixes like C are resolved against the +Windows Registry to the correct filesystem. + +=item * + +Any backslash (C<\>) characters in the path are replaced +with forward slashes so that libguestfs can process it. + +=item * + +The path is resolved case insensitively to locate the file +that should be edited. + +=back + +There are some known shortcomings: + +=over 4 + +=item * + +Some NTFS symbolic links may not be followed correctly. + +=item * + +NTFS junction points that cross filesystems are not followed. + +=back + +=cut + +sub windows_path +{ + my $g = shift; + my $root = shift; + my $filename = shift; + + # Deal with drive letters. + if ($filename =~ /^([a-z]):(.*)/i) { + $filename = $2; + my $drive_letter = $1; + + # Look up the drive letter in the drive mapping table. We + # have to do a case insensitive comparison, the slow way. + my $device; + my %drives = $g->inspect_get_drive_mappings ($root); + foreach (keys %drives) { + if (lc $_ eq lc $drive_letter) { + $device = $drives{$_}; + last; + } + } + + die __x("virt-edit: drive '{x}:' not found\n", x => $drive_letter) + unless defined $device; + + # Unmount current disk and remount $device. + $g->umount_all (); + $g->mount_options ("", $device, "/"); + } + + # Replace any backslashes in the rest of the path with + # forward slashes. + $filename =~ s{\\}{/}g; + + # If the user put \foo on the command line without quoting it + # properly, then we'll see that here as a bare path. Add a more + # descriptive error message here. + if (substr ($filename, 0, 1) ne "/") { + die __x("virt-edit: '{f}' does not start with a / or \\ character. +If you are using Windows style paths with backslashes like C:\\foo.txt +then don't forget that you must quote them with single quotes to +prevent the shell from munging the backslashes.\n", + f => $filename) + } + + # Case sensitivity. + $filename = $g->case_sensitive_path ($filename); + + return $filename; +} + +=head1 USING GUESTFISH + +L is a more powerful, lower level tool which you can use +when C doesn't work. + +Using C is approximately equivalent to doing: + + guestfish --rw -i -d domname edit /file + +where C is the name of the libvirt guest, and C is the +full path to the file. + +The command above uses libguestfs's guest inspection feature and so +does not work on guests that libguestfs cannot inspect, or on things +like arbitrary disk images that don't contain guests. To edit a file +on a disk image directly, use: + + guestfish --rw -a disk.img -m /dev/sda1 edit /file + +where C is the disk image, C is the filesystem +within the disk image to edit, and C is the full path to the +file. + +C cannot create new files. Use the guestfish commands +C, C or C instead: + + guestfish --rw -i -d domname touch /newfile + + guestfish --rw -i -d domname write /newfile "new content" + + guestfish --rw -i -d domname upload localfile /newfile + +C cannot edit multiple files, but guestfish can +do it like this: + + guestfish --rw -i -d domname edit /file1 : edit /file2 + +=cut + +exit 0; + =head1 ENVIRONMENT VARIABLES =over 4 @@ -287,11 +486,20 @@ If not set, C is used. =back +=head1 SHELL QUOTING + +Libvirt guest names can contain arbitrary characters, some of which +have meaning to the shell such as C<#> and space. You may need to +quote or escape these characters on the command line. See the shell +manual page L for details. + =head1 SEE ALSO L, L, L, +L, +L, L, L, L, @@ -305,7 +513,7 @@ Richard W.M. Jones L =head1 COPYRIGHT -Copyright (C) 2009-2010 Red Hat Inc. +Copyright (C) 2009-2011 Red Hat 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