[Libguestfs] [PATCH] builder: add an arch field to sources read from indexes

[Pino Toscano]

Add an architecture field for all the entries in each index, so we know
which architecture they are (not used right now, but will be in the
future).

The problematic part here is properly marking with the correct
architecture: since we only know the current index on libguestfs.org
contains x86_64/amd64 images, entries coming from it are marked that
way; images in all the other indexes (user-provided ones) are not known
to us, so assume they are using the same architecture as virt-builder,
hence the special "@same".
---
 builder/builder.ml       |  5 +++--
 builder/cmdline.ml       | 16 +++++++++-------
 builder/index_parser.ml  |  6 +++++-
 builder/index_parser.mli |  3 ++-
 4 files changed, 19 insertions(+), 11 deletions(-)

diff --git a/builder/builder.ml b/builder/builder.ml
index 80ccef7..d6d7570 100644
--- a/builder/builder.ml
+++ b/builder/builder.ml
@@ -42,7 +42,7 @@ let main () =
     edit, firstboot, run, format, gpg, hostname, install, list_format, links,
     memsize, mkdirs,
     network, output, password_crypto, quiet, root_password, scrub,
-    scrub_logfile, selinux_relabel, size, smp, sources, sync, timezone,
+    scrub_logfile, selinux_relabel, size, smp, sources, indexarch, sync, timezone,
     update, upload, writes =
     parse_cmdline () in
 
@@ -143,7 +143,8 @@ let main () =
           let sigchecker =
             Sigchecker.create ~debug ~gpg ~check_signature
               ~gpgkey:(Sigchecker.Fingerprint fingerprint) in
-          Index_parser.get_index ~prog ~debug ~downloader ~sigchecker source
+          Index_parser.get_index ~prog ~debug ~downloader ~sigchecker
+            ~arch:indexarch source
       ) sources
     ) in
 
diff --git a/builder/cmdline.ml b/builder/cmdline.ml
index e9e47ae..8959429 100644
--- a/builder/cmdline.ml
+++ b/builder/cmdline.ml
@@ -31,6 +31,8 @@ open Printf
 let prog = Filename.basename Sys.executable_name
 
 let default_source = "http://libguestfs.org/download/builder/index.asc"
+(* So far images in the "default_source" index were x86_64/amd64. *)
+let default_source_architecture = "x86_64"
 
 let parse_cmdline () =
   let display_version () =
@@ -408,18 +410,18 @@ read the man page virt-builder(1).
       ) in
 
   (* Check source(s) and fingerprint(s), or use environment or default. *)
-  let sources =
+  let sources, indexarch =
     let list_split = function "" -> [] | str -> string_nsplit "," str in
     let rec repeat x = function
       | 0 -> [] | 1 -> [x]
       | n -> x :: repeat x (n-1)
     in
 
-    let sources =
-      if sources <> [] then sources
+    let sources, indexarch =
+      if sources <> [] then sources, "@same"
       else (
-        try list_split (Sys.getenv "VIRT_BUILDER_SOURCE")
-        with Not_found -> [ default_source ]
+        try list_split (Sys.getenv "VIRT_BUILDER_SOURCE"), "@same"
+        with Not_found -> [ default_source ], default_source_architecture
       ) in
     let fingerprints =
       if fingerprints <> [] then fingerprints
@@ -447,12 +449,12 @@ read the man page virt-builder(1).
     assert (nr_sources > 0);
 
     (* Combine the sources and fingerprints into a single list of pairs. *)
-    List.combine sources fingerprints in
+    List.combine sources fingerprints, indexarch in
 
   mode, arg,
   attach, cache, check_signature, curl, debug, delete, delete_on_failure,
   edit, firstboot, run, format, gpg, hostname, install, list_format, links,
   memsize, mkdirs,
   network, output, password_crypto, quiet, root_password, scrub,
-  scrub_logfile, selinux_relabel, size, smp, sources, sync, timezone,
+  scrub_logfile, selinux_relabel, size, smp, sources, indexarch, sync, timezone,
   update, upload, writes
diff --git a/builder/index_parser.ml b/builder/index_parser.ml
index 2d4a642..0b9a1b9 100644
--- a/builder/index_parser.ml
+++ b/builder/index_parser.ml
@@ -37,6 +37,7 @@ and entry = {
   lvexpand : string option;
   notes : (string * string) list;
   hidden : bool;
+  arch : string;
 
   sigchecker : Sigchecker.t;
 }
@@ -53,6 +54,7 @@ let print_entry chan (name, { printable_name = printable_name;
                               expand = expand;
                               lvexpand = lvexpand;
                               notes = notes;
+                              arch = arch;
                               hidden = hidden }) =
   let fp fs = fprintf chan fs in
   fp "[%s]\n" name;
@@ -91,6 +93,7 @@ let print_entry chan (name, { printable_name = printable_name;
   | None -> ()
   | Some lvexpand -> fp "lvexpand=%s\n" lvexpand
   );
+  fp "arch=%s\n" arch;
   List.iter (
     fun (lang, notes) ->
       match lang with
@@ -108,7 +111,7 @@ and field = string * string option * string    (* key + subkey + value *)
 (* Calls yyparse in the C code. *)
 external parse_index : string -> sections = "virt_builder_parse_index"
 
-let get_index ~prog ~debug ~downloader ~sigchecker source =
+let get_index ~prog ~debug ~downloader ~sigchecker ~arch source =
   let corrupt_file () =
     eprintf (f_"\nThe index file downloaded from '%s' is corrupt.\nYou need to ask the supplier of this file to fix it and upload a fixed version.\n")
       source;
@@ -255,6 +258,7 @@ let get_index ~prog ~debug ~downloader ~sigchecker source =
                         lvexpand = lvexpand;
                         notes = notes;
                         hidden = hidden;
+                        arch = arch;
                         sigchecker = sigchecker } in
           n, entry
       ) sections in
diff --git a/builder/index_parser.mli b/builder/index_parser.mli
index 3c679b3..4fe9a8a 100644
--- a/builder/index_parser.mli
+++ b/builder/index_parser.mli
@@ -31,8 +31,9 @@ and entry = {
   lvexpand : string option;
   notes : (string * string) list;
   hidden : bool;
+  arch : string;
 
   sigchecker : Sigchecker.t;
 }
 
-val get_index : prog:string -> debug:bool -> downloader:Downloader.t -> sigchecker:Sigchecker.t -> string -> index
+val get_index : prog:string -> debug:bool -> downloader:Downloader.t -> sigchecker:Sigchecker.t -> arch:string -> string -> index
-- 
1.8.3.1