10:11 a.m.
But allow the warning to be turned off using --no-warn-if-partition.
Ming Xie tried to create a bootable USB key using
'virt-p2v-make-disk -o /dev/sdX1'. That works, but doesn't create a
bootable key because it puts everything into the first partition.
Emit a warning if someone tries to do this to try to prevent user
error:
virt-builder: warning: output device (/dev/sdb1) is a partition. If you
are writing to a USB key or external drive then you probably need to write
to the whole device, not to a partition. If this warning is wrong then you
can disable it with --no-warn-if-partition
---
builder/builder.ml | 9 +++++++++
builder/cmdline.ml | 6 ++++++
builder/cmdline.mli | 1 +
builder/virt-builder.pod | 9 +++++++++
4 files changed, 25 insertions(+)
diff --git a/builder/builder.ml b/builder/builder.ml
index 3c17ccd..affce10 100644
--- a/builder/builder.ml
+++ b/builder/builder.ml
@@ -280,6 +280,15 @@ let main () =
(* --- If we get here, we want to create a guest. --- *)
+ (* Warn if the user might be writing to a partition on a USB key. *)
+ (match cmdline.output with
+ | Some device when is_partition device ->
+ if cmdline.warn_if_partition then
+ warning (f_"output device (%s) is a partition. If you are writing to a USB
key or external drive then you probably need to write to the whole device, not to a
partition. If this warning is wrong then you can disable it with
--no-warn-if-partition")
+ device;
+ | Some _ | None -> ()
+ );
+
(* Download the template, or it may be in the cache. *)
let template =
let template, delete_on_exit =
diff --git a/builder/cmdline.ml b/builder/cmdline.ml
index f872bd4..7b33013 100644
--- a/builder/cmdline.ml
+++ b/builder/cmdline.ml
@@ -51,6 +51,7 @@ type cmdline = {
smp : int option;
sources : (string * string) list;
sync : bool;
+ warn_if_partition : bool;
}
let parse_cmdline () =
@@ -115,6 +116,7 @@ let parse_cmdline () =
let add_source arg = sources := arg :: !sources in
let sync = ref true in
+ let warn_if_partition = ref true in
let argspec = [
"--arch", Arg.Set_string arch, "arch" ^ " " ^
s_"Set the output architecture";
@@ -163,6 +165,8 @@ let parse_cmdline () =
"--smp", Arg.Int set_smp, "vcpus" ^ " " ^
s_"Set number of vCPUs";
"--source", Arg.String add_source, "URL" ^ " " ^
s_"Set source URL";
"--no-sync", Arg.Clear sync, " " ^ s_"Do not
fsync output file on exit";
+ "--no-warn-if-partition", Arg.Clear warn_if_partition,
+ " " ^ s_"Do not warn if
writing to a partition";
] in
let customize_argspec, get_customize_ops = Customize_cmdline.argspec () in
let customize_argspec =
@@ -212,6 +216,7 @@ read the man page virt-builder(1).
let smp = !smp in
let sources = List.rev !sources in
let sync = !sync in
+ let warn_if_partition = !warn_if_partition in
(* No arguments and machine-readable mode? Print some facts. *)
if args = [] && machine_readable then (
@@ -324,4 +329,5 @@ read the man page virt-builder(1).
gpg = gpg; list_format = list_format; memsize = memsize;
network = network; ops = ops; output = output;
size = size; smp = smp; sources = sources; sync = sync;
+ warn_if_partition = warn_if_partition;
}
diff --git a/builder/cmdline.mli b/builder/cmdline.mli
index 4c201dd..854db61 100644
--- a/builder/cmdline.mli
+++ b/builder/cmdline.mli
@@ -39,6 +39,7 @@ type cmdline = {
smp : int option;
sources : (string * string) list;
sync : bool;
+ warn_if_partition : bool;
}
val parse_cmdline : unit -> cmdline
diff --git a/builder/virt-builder.pod b/builder/virt-builder.pod
index be5b568..cd3be9d 100644
--- a/builder/virt-builder.pod
+++ b/builder/virt-builder.pod
@@ -496,6 +496,15 @@ Note that you should not point I<--source> to sources that you
don't
trust (unless the source is signed by someone you do trust). See also
the I<--no-network> option.
+=item B<--no-warn-if-partition>
+
+Do not emit a warning if the output device is a partition. This
+warning avoids a common user error when writing to a USB key or
+external drive, when you should normally write to the whole device
+(S<I<--output /dev/sdX>>), not to a partition on the device
+(S<I<--output /dev/sdX1>>). Use this option to I<suppress> this
+warning.
+
=item B<-v>
=item B<--verbose>
--
2.7.4