New tool: virt-edit

Edit any file in a guest.  This was possibly previously
using guestfish, but having a separate command makes it
simpler.

The usage is simply:

  virt-edit mydomain /some/file

It runs $EDITOR or vi on the file, and if the user changes
it, uploads the result back to the VM.

.gitignore

@@ -48,6 +48,7 @@ daemon/stubs.c
 depcomp
 .deps
 df/virt-df.1
+edit/virt-edit.1
 emptydisk
 examples/hello
 examples/to-xml
@@ -73,6 +74,7 @@ html/guestfs.3.html
 html/recipes.html
 html/virt-cat.1.html
 html/virt-df.1.html
+html/virt-edit.1.html
 html/virt-inspector.1.html
 html/virt-rescue.1.html
 images/100kallnewlines

HACKING

@@ -83,6 +83,9 @@ daemon/
 df/
         The virt-df tool.
 
+edit/
+	The virt-edit tool.
+
 examples/
         The examples.
 

Makefile.am

@@ -50,6 +50,9 @@ endif
 if HAVE_RESCUE
 SUBDIRS += rescue
 endif
+if HAVE_EDIT
+SUBDIRS += edit
+endif
 
 EXTRA_DIST = \
 	guestfs.pod guestfs-actions.pod guestfs-structs.pod \

cat/virt-cat.pl

@@ -44,8 +44,9 @@ virt-cat - Display a file in a virtual machine
 C<virt-cat> is a command line tool to display the contents of C<file>
 where C<file> exists in the named virtual machine (or disk image).
 
-C<virt-cat> can be used to quickly view a single file.  For more
-complex cases you should look at the L<guestfish(1)> tool.
+C<virt-cat> can be used to quickly view a single file.  To edit a
+file, use C<virt-edit>.  For more complex cases you should look at the
+L<guestfish(1)> tool.
 
 =head1 EXAMPLES
 
@@ -164,6 +165,7 @@ print $g->download($filename, "/dev/stdout");
 
 L<guestfs(3)>,
 L<guestfish(1)>,
+L<virt-edit(1)>,
 L<Sys::Guestfs(3)>,
 L<Sys::Guestfs::Lib(3)>,
 L<Sys::Virt(3)>,

configure.ac

@@ -653,13 +653,15 @@ for pm in Pod::Usage Getopt::Long Sys::Virt Data::Dumper XML::Writer Locale::Tex
     fi
 done
 if test "x$missing_perl_modules" = "xyes"; then
-    AC_MSG_WARN([some Perl modules required to compile virt-cat, virt-df, virt-inspector and virt-rescue are missing])
+    AC_MSG_WARN([some Perl modules required to compile virt-cat, virt-df, virt-edit, virt-inspector and virt-rescue are missing])
 fi
 
 AM_CONDITIONAL([HAVE_CAT],
     [test "x$PERL" != "xno" -a "x$missing_perl_modules" != "xyes"])
 AM_CONDITIONAL([HAVE_DF],
     [test "x$PERL" != "xno" -a "x$missing_perl_modules" != "xyes"])
+AM_CONDITIONAL([HAVE_EDIT],
+    [test "x$PERL" != "xno" -a "x$missing_perl_modules" != "xyes"])
 AM_CONDITIONAL([HAVE_INSPECTOR],
     [test "x$PERL" != "xno" -a "x$missing_perl_modules" != "xyes"])
 AM_CONDITIONAL([HAVE_RESCUE],
@@ -701,6 +703,7 @@ AC_CONFIG_FILES([Makefile
                  haskell/Makefile
                  cat/Makefile
                  df/Makefile
+                 edit/Makefile
                  inspector/Makefile
                  rescue/Makefile
                  libguestfs.pc
@@ -734,6 +737,8 @@ echo -n "virt-cat ............................ "
 if test "x$HAVE_CAT" = "x"; then echo "yes"; else echo "no"; fi
 echo -n "virt-df ............................. "
 if test "x$HAVE_DF" = "x"; then echo "yes"; else echo "no"; fi
+echo -n "virt-edit ........................... "
+if test "x$HAVE_EDIT" = "x"; then echo "yes"; else echo "no"; fi
 echo -n "virt-inspector ...................... "
 if test "x$HAVE_INSPECTOR" = "x"; then echo "yes"; else echo "no"; fi
 echo -n "virt-rescue ......................... "

edit/Makefile.am

@@ -0,0 +1,48 @@
+# libguestfs virt-edit
+# Copyright (C) 2009 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
+# the Free Software Foundation; either version 2 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, write to the Free Software
+# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+EXTRA_DIST = \
+	run-edit-locally \
+	virt-edit.pl
+
+if HAVE_EDIT
+
+man_MANS = virt-edit.1
+
+noinst_DATA = @top_builddir@/html/virt-edit.1.html
+
+virt-edit.1: virt-edit.pl
+	$(POD2MAN) \
+	  --section 1 \
+	  -c "Virtualization Support" \
+	  --release "$(PACKAGE_NAME)-$(PACKAGE_VERSION)" \
+	  $< > $@
+
+@top_builddir@/html/virt-edit.1.html: virt-edit.pl
+	mkdir -p @top_builddir@/html
+	cd @top_builddir@ && pod2html \
+	  --css 'pod.css' \
+	  --title 'virt-edit, edit a file in a virtual machine' \
+	  --htmldir html \
+	  --outfile html/virt-edit.1.html \
+	  edit/$<
+
+install-data-hook:
+	mkdir -p $(DESTDIR)$(bindir)
+	install -m 0755 virt-edit.pl $(DESTDIR)$(bindir)/virt-edit
+
+endif

edit/run-edit-locally

@@ -0,0 +1,52 @@
+#!/usr/bin/perl
+# virt-edit
+# Copyright (C) 2009 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
+# the Free Software Foundation; either version 2 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, write to the Free Software
+# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+# This script sets up the environment so you can run virt-edit in place
+# without needing to do 'make install' first. You can also run virt-edit
+# by creating a symlink to this script and putting it in your path.
+#
+# Use it like this:
+#   ./run-edit-locally [usual virt-edit args ...]
+
+use strict;
+use warnings;
+
+use File::Basename qw(dirname);
+use File::Spec;
+use Cwd qw(abs_path);
+
+my $path = $0;
+
+# Follow symlinks until we get to the real file
+while(-l $path) {
+    my $link = readlink($path);
+    if(File::Spec->file_name_is_absolute($link)) {
+        $path = $link;
+    } else {
+        $path = File::Spec->catfile(dirname($path), $link);
+    }
+}
+
+# Get the absolute path of the parent directory
+$path = abs_path(dirname($path).'/..');
+
+$ENV{LD_LIBRARY_PATH} = $path.'/src/.libs';
+$ENV{LIBGUESTFS_PATH} = $path.'/appliance';
+$ENV{PERL5LIB}        = $path.'/perl/blib/lib:'.$path.'/perl/blib/arch';
+
+exec('perl', $path.'/edit/virt-edit.pl', @ARGV);

edit/virt-edit.pl

@@ -0,0 +1,210 @@
+#!/usr/bin/perl -w
+# virt-edit
+# Copyright (C) 2009 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
+# the Free Software Foundation; either version 2 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, write to the Free Software
+# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+
+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 Pod::Usage;
+use Getopt::Long;
+use File::Temp qw/tempfile/;
+use Locale::TextDomain 'libguestfs';
+
+=encoding utf8
+
+=head1 NAME
+
+virt-edit - Edit a file in a virtual machine
+
+=head1 SYNOPSIS
+
+ virt-edit [--options] domname file
+
+ virt-edit [--options] disk.img [disk.img ...] file
+
+=head1 DESCRIPTION
+
+C<virt-edit> is a command line tool to edit C<file> where C<file>
+exists in the named virtual machine (or disk image).
+
+B<Note> you must I<not> use virt-edit on live virtual machines.  If
+you do this, you risk disk corruption in the VM.
+
+If you want to just view a file, use L<virt-cat(1)>.  For more complex
+cases you should look at the L<guestfish(1)> tool.
+
+=head1 EXAMPLES
+
+ virt-edit mydomain /boot/grub/grub.conf
+
+ virt-edit mydomain /etc/passwd
+
+=head1 OPTIONS
+
+=over 4
+
+=cut
+
+my $help;
+
+=item B<--help>
+
+Display brief help.
+
+=cut
+
+my $version;
+
+=item B<--version>
+
+Display version number and exit.
+
+=cut
+
+my $uri;
+
+=item B<--connect URI> | B<-c URI>
+
+If using libvirt, connect to the given I<URI>.  If omitted, then we
+connect to the default libvirt hypervisor.
+
+If you specify guest block devices directly, then libvirt is not used
+at all.
+
+=back
+
+=cut
+
+GetOptions ("help|?" => \$help,
+            "version" => \$version,
+            "connect|c=s" => \$uri,
+    ) or pod2usage (2);
+pod2usage (1) if $help;
+if ($version) {
+    my $g = Sys::Guestfs->new ();
+    my %h = $g->version ();
+    print "$h{major}.$h{minor}.$h{release}$h{extra}\n";
+    exit
+}
+
+pod2usage (__"virt-edit: no image, VM names or filenames to edit given")
+    if @ARGV <= 1;
+
+my $filename = pop @ARGV;
+
+my $g;
+if ($uri) {
+    $g = open_guest (\@ARGV, address => $uri, rw => 1);
+} else {
+    $g = open_guest (\@ARGV, rw => 1);
+}
+
+$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 __"no root device found in this operating system image" if @roots == 0;
+die __"multiboot operating systems are not supported by virt-edit" if @roots > 1;
+my $root_dev = $roots[0];
+
+my $os = $oses->{$root_dev};
+mount_operating_system ($g, $os, 0);
+
+my ($fh, $tempname) = tempfile ();
+
+# Allow this to fail in case eg. the file does not exist.
+$g->download($filename, $tempname);
+
+my $oldctime = (stat ($tempname))[10];
+
+my $editor = $ENV{EDITOR};
+$editor ||= "vi";
+system ("$editor $tempname") == 0
+    or die "edit failed: $editor: $?";
+
+my $newctime = (stat ($tempname))[10];
+
+if ($oldctime != $newctime) {
+    $g->upload ($tempname, $filename)
+} else {
+    print __"File not changed.\n";
+}
+
+$g->sync ();
+$g->umount_all ();
+
+undef $g;
+
+exit 0;
+
+=head1 ENVIRONMENT VARIABLES
+
+=over 4
+
+=item C<EDITOR>
+
+If set, this string is used as the editor.  It may contain arguments,
+eg. C<"emacs -nw">
+
+If not set, C<vi> is used.
+
+=back
+
+=head1 SEE ALSO
+
+L<guestfs(3)>,
+L<guestfish(1)>,
+L<virt-cat(1)>,
+L<Sys::Guestfs(3)>,
+L<Sys::Guestfs::Lib(3)>,
+L<Sys::Virt(3)>,
+L<http://libguestfs.org/>.
+
+=head1 AUTHOR
+
+Richard W.M. Jones L<http://et.redhat.com/~rjones/>
+
+=head1 COPYRIGHT
+
+Copyright (C) 2009 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
+the Free Software Foundation; either version 2 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, write to the Free Software
+Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.

po/POTFILES.in

@@ -56,6 +56,7 @@ daemon/xattr.c
 daemon/zero.c
 daemon/zerofree.c
 df/virt-df.pl
+edit/virt-edit.pl
 fish/alloc.c
 fish/cmds.c
 fish/completion.c