X-Git-Url: http://git.annexia.org/?a=blobdiff_plain;f=tools%2Fvirt-edit;h=887ef4b64609dad086b13e9e6834a26f4290c459;hb=607dcadd2dc7883865ada5ae158e750f19dfff67;hp=d4e11dbfa3a58f7c6167247eb780fdf457a19a58;hpb=8f6d8b05152fda68e0c01848c0e5239e0093548a;p=libguestfs.git

diff --git a/tools/virt-edit b/tools/virt-edit
index d4e11db..887ef4b 100755
--- a/tools/virt-edit
+++ b/tools/virt-edit
@@ -92,6 +92,22 @@ Display version number and exit.
 
 =cut
 
+my $backup;
+
+=item B<--backup extension> | B<-b extension>
+
+Create a backup of the original file I<in the guest disk image>.
+The backup has the original filename with C<extension> added.
+
+Usually the first character of C<extension> 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 +120,23 @@ 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 +155,9 @@ 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) {
@@ -139,9 +174,9 @@ 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 ();
@@ -163,7 +198,7 @@ my $root_dev = $roots[0];
 my $os = $oses->{$root_dev};
 mount_operating_system ($g, $os, 0);
 
-my ($fh_not_used, $tempname) = tempfile ();
+my ($fh_not_used, $tempname) = tempfile (UNLINK => 1);
 
 # Allow this to fail in case eg. the file does not exist.
 $g->download($filename, $tempname);
@@ -186,7 +221,7 @@ 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: $!";
@@ -203,7 +238,25 @@ if (!defined $expr) {
 }
 
 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 ();
 }
@@ -287,6 +340,13 @@ If not set, C<vi> 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<sh(1)> for details.
+
 =head1 SEE ALSO
 
 L<guestfs(3)>,