v2v: -i ova: Allow directories and ZIP files to be used as input (RHBZ#1152998).

OVA is not a particularly well-specified format.  The specification
allows a directory to be an OVA, so enable that.  The spec doesn't
mention that ZIP can be used in place of tar, but since we have seen
these in the wild, allow that too.

README

@@ -179,6 +179,8 @@ The full requirements are described below.
 +--------------+-------------+---+-----------------------------------------+
 | gtk2         |             | O | Used by virt-p2v user interface.        |
 +--------------+-------------+---+-----------------------------------------+
+| zip, unzip   |             | O | Used by virt-v2v for OVA files.         |
++--------------+-------------+---+-----------------------------------------+
 | python-evtx  |             | O | Used by virt-log to parse Windows       |
 |              |             |   | Event Log files.                        |
 +--------------+-------------+---+-----------------------------------------+

configure.ac

@@ -720,6 +720,13 @@ if test "x$YACC" = "xyacc"; then
     AC_MSG_FAILURE([GNU 'bison' is required (yacc won't work).])
 fi
 
+dnl zip/unzip, used by virt-v2v
+AC_PATH_PROGS([ZIP],[zip],[no])
+AC_DEFINE_UNQUOTED([ZIP],["$ZIP"],[Name of zip program.])
+AM_CONDITIONAL([HAVE_ZIP],[test "x$ZIP" != "xno"])
+AC_PATH_PROGS([UNZIP],[unzip],[no])
+AC_DEFINE_UNQUOTED([UNZIP],["$UNZIP"],[Name of unzip program.])
+
 dnl Check for QEMU for running binaries on this $host_cpu, fall
 dnl back to basic 'qemu'.  Allow the user to override it.
 qemu_system="$(

v2v/input_ova.ml

@@ -36,13 +36,37 @@ object
   method as_options = "-i ova " ^ ova
 
   method source () =
-    (* Extract ova (tar) file. *)
-    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;
+    (* Extract ova file. *)
+    let exploded =
+      (* The spec allows a directory to be specified as an ova.  This
+       * is also pretty convenient.
+       *)
+      if is_directory ova then ova
+      else (
+        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;
+          tmpdir
+        | `Zip ->
+          (* However, although not permitted by the spec, people ship
+           * zip files as ova too.
+           *)
+          let cmd = sprintf "unzip%s -j -d %s %s"
+            (if verbose then "" else " -q")
+            (quote tmpdir) (quote ova) in
+          if verbose then printf "%s\n%!" cmd;
+          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") ova
+      ) in
 
-    let files = Sys.readdir tmpdir in
+    let files = Sys.readdir exploded in
     let ovf = ref "" in
     (* Search for the ovf file. *)
     Array.iter (
@@ -58,13 +82,13 @@ object
     Array.iter (
       fun mf ->
         if Filename.check_suffix mf ".mf" then (
-          let chan = open_in (tmpdir // mf) in
+          let chan = open_in (exploded // mf) in
           let rec loop () =
             let line = input_line chan in
             if Str.string_match rex line 0 then (
               let disk = Str.matched_group 1 line in
               let expected = Str.matched_group 2 line in
-              let cmd = sprintf "sha1sum %s" (quote (tmpdir // disk)) in
+              let cmd = sprintf "sha1sum %s" (quote (exploded // disk)) in
               let out = external_command ~prog cmd in
               match out with
               | [] ->
@@ -86,7 +110,7 @@ object
     ) files;
 
     (* Parse the ovf file. *)
-    let xml = read_whole_file (tmpdir // ovf) in
+    let xml = read_whole_file (exploded // ovf) in
     let doc = Xml.parse_memory xml in
 
     (* Handle namespaces. *)
@@ -164,7 +188,7 @@ object
           let expr = sprintf "/ovf:Envelope/ovf:References/ovf:File[@ovf:id='%s']/@ovf:href" file_ref in
           let file_name = xpath_to_string expr "" in
           let disk = {
-            s_qemu_uri= tmpdir // file_name;
+            s_qemu_uri= exploded // file_name;
             s_format = Some "vmdk";
             s_target_dev = Some target_dev;
           } in