[Libguestfs] [PATCH 2/3] v2v: -i ova: Refactor constructing zcat command.
---
v2v/input_ova.ml | 23 ++++++++++++-----------
1 file changed, 12 insertions(+), 11 deletions(-)
diff --git a/v2v/input_ova.ml b/v2v/input_ova.ml
index c85cca508..e21de35fb 100644
--- a/v2v/input_ova.ml
+++ b/v2v/input_ova.ml
@@ -40,6 +40,10 @@ let libvirt_supports_json_raw_driver () =
else
true
+let zcat_command_of_format = function
+ | `GZip -> "gzip -c -d"
+ | `XZ -> "xz -c -d"
+
(* Untar part or all files from tar archive. If [paths] is specified it is
* a list of paths in the tar archive.
*)
@@ -50,12 +54,10 @@ let untar ?format ?(paths = []) file outdir =
| None ->
sprintf "tar -xf %s -C %s %s"
(quote file) (quote outdir) paths
- | Some `GZip ->
- sprintf "gzip -c -d %s | tar -xf - -C %s %s"
- (quote file) (quote outdir) paths
- | Some `XZ ->
- sprintf "xz -c -d %s | tar -xf - -C %s %s"
- (quote file) (quote outdir) paths in
+ | Some ((`GZip|`XZ) as format) ->
+ sprintf "%s %s | tar -xf - -C %s %s"
+ (zcat_command_of_format format) (quote file)
+ (quote outdir) paths in
if shell_command cmd <> 0 then
error (f_"error unpacking %s, see earlier error messages") file
@@ -72,10 +74,10 @@ let untar_metadata file outdir =
untar ~paths:files file outdir
(* Uncompress the first few bytes of [file] and return it as
- * [(bytes, len)]. [zcat] is the command to use (eg. zcat or xzcat).
+ * [(bytes, len)].
*)
-let uncompress_head zcat file =
- let cmd = sprintf "%s %s" zcat (quote file) in
+let uncompress_head format file =
+ let cmd = sprintf "%s %s" (zcat_command_of_format format) (quote file) in
let chan_out, chan_in, chan_err = Unix.open_process_full cmd [||] in
let b = Bytes.create 512 in
let len = input chan_out b 0 (Bytes.length b) in
@@ -89,8 +91,7 @@ let uncompress_head zcat file =
* type of the uncompressed content (if known).
*)
let uncompressed_type format file =
- let zcat = match format with `GZip -> "zcat" | `XZ -> "xzcat"
in
- let head, headlen = uncompress_head zcat file in
+ let head, headlen = uncompress_head format file in
let tmpfile, chan =
Filename.open_temp_file "ova.file." "" in
output chan head 0 headlen;
--
2.12.0