[Libguestfs] [PATCH 1/2] v2v: support tar.gz and tar.xz ova files

When dealing with a ova detected as gzip of xz, uncompress few bytes of it to check whether it is a compressed tarball, and if so untar it. Related to RHBZ#1186800. --- v2v/input_ova.ml | 48 ++++++++++++++++++++++++++++++++++++++++++------ 1 file changed, 42 insertions(+), 6 deletions(-) diff --git a/v2v/input_ova.ml b/v2v/input_ova.ml index 74db1f7..a84037d 100644 --- a/v2v/input_ova.ml +++ b/v2v/input_ova.ml @@ -43,13 +43,32 @@ object *) if is_directory ova then ova else ( + let uncompress_head zcat file = + let cmd = sprintf "%s %s" zcat (quote file) in + let chan_out, chan_in, chan_err = Unix.open_process_full cmd [||] in + let buf = String.create 512 in + let len = input chan_out buf 0 (String.length buf) in + (* We're expecting the subprocess to fail because we close + * the pipe early, so: + *) + ignore (Unix.close_process_full (chan_out, chan_in, chan_err)); + + let tmpfile, chan = Filename.open_temp_file ~temp_dir:tmpdir "ova.file." "" in + output chan buf 0 len; + close_out chan; + + tmpfile in + + let untar ?(format = "") file outdir = + let cmd = sprintf "tar -x%sf %s -C %s" format (quote file) (quote outdir) in + if verbose then printf "%s\n%!" cmd; + if Sys.command cmd <> 0 then + error (f_"error unpacking %s, see earlier error messages") ova in + match detect_file_type ova with | `Tar -> (* Normal ovas are tar file (not compressed). *) - let cmd = sprintf "tar -xf %s -C %s" (quote ova) (quote tmpdir) in - if verbose then printf "%s\n%!" cmd; - if Sys.command cmd <> 0 then - error (f_"error unpacking %s, see earlier error messages") ova; + untar ova tmpdir; tmpdir | `Zip -> (* However, although not permitted by the spec, people ship @@ -62,8 +81,25 @@ object if Sys.command cmd <> 0 then error (f_"error unpacking %s, see earlier error messages") ova; tmpdir - | `GZip | `XZ | `Unknown -> - error (f_"%s: unsupported file format\n\nFormats which we currently understand for '-i ova' are: uncompressed tar, zip") ova + | (`GZip|`XZ) as format -> + let zcat, tar_fmt = + match format with + | `GZip -> "zcat", "z" + | `XZ -> "xzcat", "J" + | _ -> assert false in + let tmpfile = uncompress_head zcat ova in + let tmpfiletype = detect_file_type tmpfile in + (* Remove tmpfile from tmpdir, to leave it empty. *) + Sys.remove tmpfile; + (match tmpfiletype with + | `Tar -> + untar ~format:tar_fmt ova tmpdir; + tmpdir + | `Zip | `GZip | `XZ | `Unknown -> + error (f_"%s: unsupported file format\n\nFormats which we currently understand for '-i ova' are: tar (uncompressed, compress with gzip or xz), zip") ova + ) + | `Unknown -> + error (f_"%s: unsupported file format\n\nFormats which we currently understand for '-i ova' are: tar (uncompressed, compress with gzip or xz), zip") ova ) in (* Exploded path must be absolute (RHBZ#1155121). *) -- 2.1.0