[PATCH v1 2/2] oxenstored: make Quota.t pure

[Edwin Török <edwin.torok@xxxxxxxxx>]

Now that we no longer have a hashtable inside we can make Quota.t pure,
and push the mutable update to its callers.
Store.t already had a mutable Quota.t field.

No functional change.

Signed-off-by: Edwin Török <edwin.torok@xxxxxxxxx>
---
 tools/ocaml/xenstored/quota.ml |  8 ++++----
 tools/ocaml/xenstored/store.ml | 17 ++++++++++-------
 2 files changed, 14 insertions(+), 11 deletions(-)

diff --git a/tools/ocaml/xenstored/quota.ml b/tools/ocaml/xenstored/quota.ml
index f6e28ecc6a..1f652040d8 100644
--- a/tools/ocaml/xenstored/quota.ml
+++ b/tools/ocaml/xenstored/quota.ml
@@ -33,7 +33,7 @@ module DomidMap = Map.Make(Domid)
 type t = {
   maxent: int;               (* max entities per domU *)
   maxsize: int;              (* max size of data store in one node *)
-  mutable cur: int DomidMap.t; (* current domains quota *)
+  cur: int DomidMap.t; (* current domains quota *)
 }
 
 let to_string quota domid =
@@ -76,10 +76,10 @@ let update_entry quota_cur id diff =
   else DomidMap.add id nb quota_cur
 
 let del_entry quota id =
-  quota.cur <- update_entry quota.cur id (-1)
+  {quota with cur = update_entry quota.cur id (-1)}
 
 let add_entry quota id =
-  quota.cur <- update_entry quota.cur id (+1)
+  {quota with cur = update_entry quota.cur id (+1)}
 
 let merge orig_quota mod_quota dest_quota =
   let fold_merge id nb dest =
@@ -87,5 +87,5 @@ let merge orig_quota mod_quota dest_quota =
     | 0 -> dest (* not modified *)
     | diff -> update_entry dest id diff (* update with [x=x+diff] *)
   in
-  dest_quota.cur <- DomidMap.fold fold_merge mod_quota.cur dest_quota.cur
+  {dest_quota with cur = DomidMap.fold fold_merge mod_quota.cur dest_quota.cur}
   (* dest_quota = dest_quota + (mod_quota - orig_quota) *)
diff --git a/tools/ocaml/xenstored/store.ml b/tools/ocaml/xenstored/store.ml
index 38a4945372..9b8dd2812d 100644
--- a/tools/ocaml/xenstored/store.ml
+++ b/tools/ocaml/xenstored/store.ml
@@ -85,7 +85,9 @@ module Node = struct
       raise Define.Permission_denied;
     end
 
-  let rec recurse fct node = fct node; SymbolMap.iter (fun _ -> recurse fct) 
node.children
+  let rec recurse fct node acc =
+    let acc = fct node acc in
+    SymbolMap.fold (fun _ -> recurse fct) node.children acc
 
   (** [recurse_filter_map f tree] applies [f] on each node in the tree 
recursively,
       possibly removing some nodes.
@@ -408,7 +410,7 @@ let dump_buffer store = dump_store_buf store.root
 let set_node store path node orig_quota mod_quota =
   let root = Path.set_node store.root path node in
   store.root <- root;
-  Quota.merge orig_quota mod_quota store.quota
+  store.quota <- Quota.merge orig_quota mod_quota store.quota
 
 let write store perm path value =
   let node, existing = get_deepest_existing_node store path in
@@ -422,7 +424,7 @@ let write store perm path value =
   let root, node_created = path_write store perm path value in
   store.root <- root;
   if node_created
-  then Quota.add_entry store.quota owner
+  then store.quota <- Quota.add_entry store.quota owner
 
 let mkdir store perm path =
   let node, existing = get_deepest_existing_node store path in
@@ -431,7 +433,7 @@ let mkdir store perm path =
   if not (existing || (Perms.Connection.is_dom0 perm)) then Quota.check 
store.quota owner 0;
   store.root <- path_mkdir store perm path;
   if not existing then
-    Quota.add_entry store.quota owner
+    store.quota <- Quota.add_entry store.quota owner
 
 let rm store perm path =
   let rmed_node = Path.get_node store.root path in
@@ -439,7 +441,7 @@ let rm store perm path =
   | None -> raise Define.Doesnt_exist
   | Some rmed_node ->
     store.root <- path_rm store perm path;
-    Node.recurse (fun node -> Quota.del_entry store.quota (Node.get_owner 
node)) rmed_node
+    store.quota <- Node.recurse (fun node quota -> Quota.del_entry quota 
(Node.get_owner node)) rmed_node store.quota
 
 let setperms store perm path nperms =
   match Path.get_node store.root path with
@@ -450,8 +452,9 @@ let setperms store perm path nperms =
     if not ((old_owner = new_owner) || (Perms.Connection.is_dom0 perm)) then
       raise Define.Permission_denied;
     store.root <- path_setperms store perm path nperms;
-    Quota.del_entry store.quota old_owner;
-    Quota.add_entry store.quota new_owner
+    store.quota <-
+      let quota = Quota.del_entry store.quota old_owner in
+      Quota.add_entry quota new_owner
 
 let reset_permissions store domid =
   Logging.info "store|node" "Cleaning up xenstore ACLs for domid %d" domid;
-- 
2.43.0