builder: Implement --hostname (set hostname of guest).

This also makes a minor rearrangement so that the random seed, root
password, hostname setting all happen before package installation.
This keeps these configuration changes together and means that the
packages that are installed can act differently based on hostname
(which is conceivable).

builder/Makefile.am

@@ -57,6 +57,7 @@ OBJECTS = \
 	$(top_builddir)/mllib/common_gettext.cmx \
 	$(top_builddir)/mllib/common_utils.cmx \
 	$(top_builddir)/mllib/random_seed.cmx \
+	$(top_builddir)/mllib/hostname.cmx \
 	$(top_builddir)/mllib/firstboot.cmx \
 	$(top_builddir)/mllib/crypt-c.o \
 	$(top_builddir)/mllib/crypt.cmx \

builder/builder.ml

@@ -41,7 +41,7 @@ let cachedir =
 let mode, arg,
   attach, cache, check_signature, curl, debug, fingerprint,
   firstboot, run,
-  format, gpg, install, list_long, network, output,
+  format, gpg, hostname, install, list_long, network, output,
   password_crypto, quiet, root_password,
   size, source, upload =
   let display_version () =
@@ -96,6 +96,9 @@ let mode, arg,
   let format = ref "" in
   let gpg = ref "gpg" in
 
+  let hostname = ref None in
+  let set_hostname s = hostname := Some s in
+
   let install = ref [] in
   let add_install pkgs =
     let pkgs = string_nsplit "," pkgs in
@@ -180,6 +183,7 @@ let mode, arg,
     "--get-kernel", Arg.Unit get_kernel_mode,
                                             "image" ^ " " ^ s_"Get kernel from image";
     "--gpg",    Arg.Set_string gpg,         "gpg" ^ " " ^ s_"Set GPG binary/command";
+    "--hostname", Arg.String set_hostname,  "hostname" ^ " " ^ s_"Set the hostname";
     "--install", Arg.String add_install,    "pkg,pkg" ^ " " ^ s_"Add package(s) to install";
     "-l",        Arg.Unit list_mode,        " " ^ s_"List available templates";
     "--list",    Arg.Unit list_mode,        ditto;
@@ -231,6 +235,7 @@ read the man page virt-builder(1).
   let run = List.rev !run in
   let format = match !format with "" -> None | s -> Some s in
   let gpg = !gpg in
+  let hostname = !hostname in
   let install = !install in
   let list_long = !list_long in
   let network = !network in
@@ -283,7 +288,7 @@ read the man page virt-builder(1).
   mode, arg,
   attach, cache, check_signature, curl, debug, fingerprint,
   firstboot, run,
-  format, gpg, install, list_long, network, output,
+  format, gpg, hostname, install, list_long, network, output,
   password_crypto, quiet, root_password,
   size, source, upload
 
@@ -571,6 +576,48 @@ let root =
 (* Set the random seed. *)
 let () = ignore (Random_seed.set_random_seed g root)
 
+(* Set the hostname. *)
+let () =
+  match hostname with
+  | None -> ()
+  | Some hostname ->
+    ignore (Hostname.set_hostname g root hostname)
+
+(* Root password.
+ * Note 'None' means that we randomize the root password.
+ *)
+let () =
+  let make_random_password () =
+    (* Get random characters from the set [A-Za-z0-9] *)
+    let chars =
+      "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789" in
+    let nr_chars = String.length chars in
+
+    let chan = open_in "/dev/urandom" in
+    let buf = String.create 16 in
+    for i = 0 to 15 do
+      buf.[i] <- chars.[Char.code (input_char chan) mod nr_chars]
+    done;
+    close_in chan;
+
+    msg "Random root password: %s [did you mean to use --root-password?]" buf;
+
+    buf
+  in
+
+  let root_password =
+    match root_password with
+    | Some pw -> pw
+    | None -> make_random_password () in
+
+  match g#inspect_get_type root with
+  | "linux" ->
+    let h = Hashtbl.create 1 in
+    Hashtbl.replace h "root" root_password;
+    set_linux_passwords ~prog ?password_crypto g root h
+  | _ ->
+    ()
+
 (* Useful wrapper for scripts. *)
 let do_run cmd =
   (* Add a prologue to the scripts:
@@ -628,41 +675,6 @@ let () =
     do_run cmd;
   )
 
-(* Root password.
- * Note 'None' means that we randomize the root password.
- *)
-let () =
-  let make_random_password () =
-    (* Get random characters from the set [A-Za-z0-9] *)
-    let chars =
-      "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789" in
-    let nr_chars = String.length chars in
-
-    let chan = open_in "/dev/urandom" in
-    let buf = String.create 16 in
-    for i = 0 to 15 do
-      buf.[i] <- chars.[Char.code (input_char chan) mod nr_chars]
-    done;
-    close_in chan;
-
-    msg "Random root password: %s [did you mean to use --root-password?]" buf;
-
-    buf
-  in
-
-  let root_password =
-    match root_password with
-    | Some pw -> pw
-    | None -> make_random_password () in
-
-  match g#inspect_get_type root with
-  | "linux" ->
-    let h = Hashtbl.create 1 in
-    Hashtbl.replace h "root" root_password;
-    set_linux_passwords ~prog ?password_crypto g root h
-  | _ ->
-    ()
-
 (* Upload files. *)
 let () =
   List.iter (

builder/test-virt-builder.sh

@@ -38,6 +38,7 @@ rm -f phony-fedora.qcow2
 ./virt-builder phony-fedora \
     --no-cache --no-check-signature \
     --size 2G --format qcow2 \
+    --hostname test.example.com \
     --root-password password:123456 \
     --upload Makefile:/Makefile \
     --firstboot Makefile --firstboot-command 'echo "hello"' \

builder/virt-builder.pod

@@ -8,8 +8,9 @@ virt-builder - Build virtual machine images quickly
 
  virt-builder [-o|--output DISKIMAGE] [--size SIZE] [--format raw|qcow2]
     [--attach ISOFILE]
-    [--install PKG,[PKG...]]
     [--root-password ...]
+    [--hostname HOSTNAME]
+    [--install PKG,[PKG...]]
     [--upload FILE:DEST]
     [--run SCRIPT] [--run-command 'CMD ARGS ...']
     [--firstboot SCRIPT] [--firstboot-command 'CMD ARGS ...']
@@ -94,6 +95,12 @@ a I<random> root password.
 
 You can also create user accounts.  See L</USERS AND PASSWORDS> below.
 
+=head2 Set the hostname
+
+ virt-builder fedora-20 --hostname virt.example.com
+
+Set the hostname to C<virt.example.com>.
+
 =head2 Installing software
 
 To install packages from the ordinary (guest) software repository
@@ -276,6 +283,11 @@ alternate home directory:
 
  virt-builder --gpg "gpg --homedir /tmp" [...]
 
+=item B<--hostname> HOSTNAME
+
+Set the hostname of the guest to C<HOSTNAME>.  You can use a
+dotted hostname.domainname (FQDN) if you want.
+
 =item B<--install> PKG[,PKG,...]
 
 Install the named packages (a comma-separated list).  These are
@@ -595,7 +607,7 @@ A new random seed is generated for the guest.
 
 =item *
 
-Packages are installed (I<--install>).
+The hostname is set (I<--hostname>).
 
 =item *
 
@@ -603,6 +615,10 @@ The root password is changed (I<--root-password>).
 
 =item *
 
+Packages are installed (I<--install>).
+
+=item *
+
 Files are uploaded (I<--upload>).
 
 =item *