Re: [Libguestfs] [PATCH 2/8] v2v: add basic support for the "deb" package manager

On Mon, 8 Aug 2016 18:38:49 +0200 Pino Toscano <ptoscano(a)redhat.com&gt; wrote: > Implement the 'remove', 'file_list_of_package', and 'file_owner' methods > of the Linux module for the "deb" package manager (dpkg basically, on > Debian and derived distributions). > > Also allow it for the main conversion code. > --- > v2v/convert_linux.ml | 2 +- > v2v/linux.ml | 23 +++++++++++++++++++++++ > 2 files changed, 24 insertions(+), 1 deletion(-) > > diff --git a/v2v/convert_linux.ml b/v2v/convert_linux.ml > index 4b1ce99..65796d6 100644 > --- a/v2v/convert_linux.ml > +++ b/v2v/convert_linux.ml > @@ -79,7 +79,7 @@ let rec convert ~keep_serial_console (g : G.guestfs) inspect source rcaps = > | "sles" | "suse-based" | "opensuse" -> `SUSE_family > | _ -> assert false in > > - assert (inspect.i_package_format = "rpm"); > + assert (inspect.i_package_format = "rpm" || inspect.i_package_format = "deb"); > > (* We use Augeas for inspection and conversion, so initialize it early. *) > Linux.augeas_init g; > diff --git a/v2v/linux.ml b/v2v/linux.ml > index ed639c1..5713f64 100644 > --- a/v2v/linux.ml > +++ b/v2v/linux.ml > @@ -48,6 +48,10 @@ and do_remove g inspect packages = > assert (List.length packages > 0); > let package_format = inspect.i_package_format in > match package_format with > + | "deb" -> > + let cmd = [ "dpkg"; "--purge" ] @ packages in > + let cmd = Array.of_list cmd in > + ignore (g#command cmd); > | "rpm" -> > let cmd = [ "rpm"; "-e" ] @ packages in > let cmd = Array.of_list cmd in > @@ -61,6 +65,12 @@ let file_list_of_package (g : Guestfs.guestfs) inspect app = > let package_format = inspect.i_package_format in > > match package_format with > + | "deb" -> > + let cmd = [| "dpkg"; "-L"; app.G.app2_name |] in > + debug "%s" (String.concat " " (Array.to_list cmd)); > + let files = g#command_lines cmd in > + let files = Array.to_list files in > + List.sort compare files > | "rpm" -> > (* Since RPM allows multiple packages installed with the same > * name, always check the full ENVR here (RHBZ#1161250). > @@ -98,6 +108,19 @@ let file_list_of_package (g : Guestfs.guestfs) inspect app = > let rec file_owner (g : G.guestfs) inspect path = > let package_format = inspect.i_package_format in > match package_format with > + | "deb" -> > + let cmd = [| "dpkg"; "-S"; path |] in > + debug "%s" (String.concat " " (Array.to_list cmd)); > + let lines = > + try g#command_lines cmd This is not good. dpkg-query command behaves differently from rpm.

First, the returned packages are all on one line separated by commas. What I came up with is this: let cmd = [| "dpkg-query"; "-S"; path |] in debug "%s" (String.concat " " (Array.to_list cmd)); (try let pkg = g#command cmd in (* What we get is a string of form "pkg1, pkg2:arch, pkg3: /path" *) let len = String.length pkg in let rec loop i = if i >= len then (* This is fishy. Internal bug? *) error (f_"internal error: file_owner: failed to process string '%s'") pkg else if pkg.[i] = ' ' && (pkg.[i-1] = ':' || pkg.[i-1] = ',') then String.sub pkg 0 (i-1) else loop (i+1) in loop 1 with Guestfs.Error msg as exn -> if String.find msg "no path found matching pattern" >= 0 then raise Not_found else raise exn ) The other concern is, whether we should escape the argument somehow. The fact is that dpkg-query accepts a glob expression, not just a simple path. If you provide it with a pattern you will get all the matching paths, each on a single line (prefixed by the package list).