[Libguestfs] [PATCH v3 4/7] resize: add function calculate_target_partitions

[Richard W.M. Jones]

On Mon, Sep 22, 2014 at 03:47:37PM +0800, Hu Tao wrote:
> And introduce parameter create_surplus to indicate whether to
> create surplus partition or not. Later this parameter will be
> used by when calculating positions for target logical partitions.
> 
> Signed-off-by: Hu Tao <hutao at cn.fujitsu.com>
> ---
>  resize/resize.ml | 14 +++++++-------
>  1 file changed, 7 insertions(+), 7 deletions(-)
> 
> diff --git a/resize/resize.ml b/resize/resize.ml
> index cfd02fc..8b43306 100644
> --- a/resize/resize.ml
> +++ b/resize/resize.ml
> @@ -1019,11 +1019,10 @@ read the man page virt-resize(1).
>     * the final list just contains partitions that need to be created
>     * on the target.
>     *)
> -  let partitions =
> -    let rec loop partnum start = function
> +    let rec calculate_target_partitions partnum start ~create_surplus = function
>        | p :: ps ->
>          (match p.p_operation with
> -        | OpDelete -> loop partnum start ps (* skip p *)
> +        | OpDelete -> calculate_target_partitions partnum start ~create_surplus ps (* skip p *)
>  
>          | OpIgnore | OpCopy ->          (* same size *)
>            (* Size in sectors. *)
> @@ -1037,7 +1036,7 @@ read the man page virt-resize(1).
>                partnum start (end_ -^ 1L);
>  
>            { p with p_target_start = start; p_target_end = end_ -^ 1L;
> -            p_target_partnum = partnum } :: loop (partnum+1) next ps
> +            p_target_partnum = partnum } :: calculate_target_partitions (partnum+1) next ~create_surplus ps
>  
>          | OpResize newsize ->           (* resized partition *)
>            (* New size in sectors. *)
> @@ -1051,12 +1050,12 @@ read the man page virt-resize(1).
>                partnum newsize start (next -^ 1L);
>  
>            { p with p_target_start = start; p_target_end = next -^ 1L;
> -            p_target_partnum = partnum } :: loop (partnum+1) next ps
> +            p_target_partnum = partnum } :: calculate_target_partitions (partnum+1) next ~create_surplus ps
>          )
>  
>        | [] ->
>          (* Create the surplus partition if there is room for it. *)
> -        if extra_partition && surplus >= min_extra_partition then (
> +        if create_surplus && extra_partition && surplus >= min_extra_partition then (
>            [ {
>              (* Since this partition has no source, this data is
>               * meaningless and not used since the operation is
> @@ -1077,6 +1076,7 @@ read the man page virt-resize(1).
>          else
>            [] in
>  
> +  let partitions =
>      (* Choose the alignment of the first partition based on the
>       * '--align-first' option.  Old virt-resize used to always align this
>       * to 64 sectors, but this causes boot failures unless we are able to
> @@ -1089,7 +1089,7 @@ read the man page virt-resize(1).
>          (* Preserve the existing start, but convert to sectors. *)
>          (List.hd partitions).p_part.G.part_start /^ sectsize in
>  
> -    loop 1 start partitions in
> +    calculate_target_partitions 1 start ~create_surplus:true partitions in
>  
>    (* Now partition the target disk. *)
>    List.iter (
> -- 
> 1.9.3

Yes, this looks fine now, although the indentation is wrong for
the final patch (but easier to review!)

Rich.

-- 
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