Libguestfs - Dec 2017 - [PATCH] v2v: bootloaders: handle no default grubby kernel (RHBZ#1519204)

When using grubby to get the default kernel of a guest, do not fail
with a bogus error like:

virt-v2v: error: libguestfs error: statns: statns_stub: path must start
with a / character

in case there is no default kernel that can be determined (e.g. because
of a bogus configuration).
---
 v2v/linux_bootloaders.ml | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/v2v/linux_bootloaders.ml b/v2v/linux_bootloaders.ml
index 8de3f0469..b820f731f 100644
--- a/v2v/linux_bootloaders.ml
+++ b/v2v/linux_bootloaders.ml
@@ -239,7 +239,10 @@ object (self)
       let res          match get_default_method with
         | MethodGrubby ->
-          Some (g#command [| "grubby"; "--default-kernel"
|])
+          let res = g#command [| "grubby";
"--default-kernel" |] in
+          (match res with
+           | "" -> None
+           | _ -> Some res)
         | MethodPerlBootloader ->
           let cmd              [| "/usr/bin/perl";
"-MBootloader::Tools"; "-e"; "
-- 
2.14.3

On Fri, Dec 01, 2017 at 02:49:30PM +0100, Pino Toscano
wrote:
> When using grubby to get the default kernel of a guest, do not fail
> with a bogus error like:
> 
> virt-v2v: error: libguestfs error: statns: statns_stub: path must start
> with a / character
> 
> in case there is no default kernel that can be determined (e.g. because
> of a bogus configuration).
> ---
>  v2v/linux_bootloaders.ml | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/v2v/linux_bootloaders.ml b/v2v/linux_bootloaders.ml
> index 8de3f0469..b820f731f 100644
> --- a/v2v/linux_bootloaders.ml
> +++ b/v2v/linux_bootloaders.ml
> @@ -239,7 +239,10 @@ object (self)
>        let res >          match get_default_method with
>          | MethodGrubby ->
> -          Some (g#command [| "grubby";
"--default-kernel" |])
> +          let res = g#command [| "grubby";
"--default-kernel" |] in
> +          (match res with
> +           | "" -> None
> +           | _ -> Some res)
>          | MethodPerlBootloader ->
>            let cmd >              [| "/usr/bin/perl";
"-MBootloader::Tools"; "-e"; "
Looks good, ACK.

Rich.

-- 
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