Remove checking all UUIDs for generating new one

The risk is ridiculous compared to the performance lost, even for several millions of messages.

migrate.lua

@@ -80,34 +80,70 @@ local function migrate_v2_to_v3()
 	end)
 end
 
+
+
+local function search_box(playername, box, uuid)
+	local e = mail.get_storage_entry(playername)
+	for _, m in ipairs(e[box]) do
+		if m.id == uuid then
+		return { time = m.time, from = m.from, to = m.to, cc = m.cc, bcc = m.bcc, subject = m.subject, body = m.body } end
+	end
+	return false
+end
+
+local function is_uuid_existing(uuid)
+    for _, k in ipairs(mail.storage:get_keys()) do
+        if string.sub(k,1,5) == "mail/" then
+			local p = string.sub(k, 6)
+			local result
+			local boxes = {"inbox", "outbox", "drafts", "trash"}
+			for _, b in ipairs(boxes) do
+				result = search_box(p, b, uuid)
+				if result then return result end
+			end
+		end
+    end
+    return false
+end
+
+local function are_message_sames(a, b)
+	return a.time == b.time
+	   and a.from == b.from
+	   and a.to == b.to
+	   and a.cc == b.cc
+	   and a.bcc == b.bcc
+	   and a.subject == b.subject
+	   and a.body == b.body
+end
+
 local function repair_box(playername, box)
 	local e = mail.get_storage_entry(playername)
 	for _, m in ipairs(e[box]) do
 		local uuid = m.id
-		local exists = mail.is_uuid_existing(uuid)
+		local exists = is_uuid_existing(uuid)
-		if exists and not mail.are_message_sames(exists, m) then
+		if exists and not are_message_sames(exists, m) then
 			local new_uuid = mail.new_uuid() -- generates a new uuid to replace doublons
 			for _, k in ipairs(mail.storage:get_keys()) do
 				if string.sub(k,1,5) == "mail/" then
 					local p = string.sub(k, 6)
 					local er = mail.get_storage_entry(p)
 					for _, r in ipairs(er.inbox) do
-						if r.id == uuid and not mail.are_message_sames(m, r) then
+						if r.id == uuid and not are_message_sames(m, r) then
 							r.id = new_uuid
 						end
 					end
 					for _, r in ipairs(er.outbox) do
-						if r.id == uuid and not mail.are_message_sames(m, r) then
+						if r.id == uuid and not are_message_sames(m, r) then
 							r.id = new_uuid
 						end
 					end
 					for _, r in ipairs(er.drafts) do
-						if r.id == uuid and not mail.are_message_sames(m, r) then
+						if r.id == uuid and not are_message_sames(m, r) then
 							r.id = new_uuid
 						end
 					end
 					for _, r in ipairs(er.trash) do
-						if r.id == uuid and not mail.are_message_sames(m, r) then
+						if r.id == uuid and not are_message_sames(m, r) then
 							r.id = new_uuid
 						end
 					end

util/uuid.lua

@@ -1,49 +1,11 @@
 -- source: https://gist.github.com/jrus/3197011
 local random = math.random
 
-function mail.search_box(playername, box, uuid)
-	local e = mail.get_storage_entry(playername)
-	for _, m in ipairs(e[box]) do
-		if m.id == uuid then
-		return { time = m.time, from = m.from, to = m.to, cc = m.cc, bcc = m.bcc, subject = m.subject, body = m.body } end
-	end
-	return false
-end
-
-function mail.is_uuid_existing(uuid)
-    for _, k in ipairs(mail.storage:get_keys()) do
-        if string.sub(k,1,5) == "mail/" then
-			local p = string.sub(k, 6)
-			local result
-			local boxes = {"inbox", "outbox", "drafts", "trash"}
-			for _, b in ipairs(boxes) do
-				result = mail.search_box(p, b, uuid)
-				if result then return result end
-			end
-		end
-    end
-    return false
-end
-
-function mail.are_message_sames(a, b)
-	return a.time == b.time
-	   and a.from == b.from
-	   and a.to == b.to
-	   and a.cc == b.cc
-	   and a.bcc == b.bcc
-	   and a.subject == b.subject
-	   and a.body == b.body
-end
-
 function mail.new_uuid()
     local template ='xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'
-    local candidate_uuid
+    return string.gsub(template, '[xy]',
-    repeat
-        candidate_uuid = string.gsub(template, '[xy]',
 		function (c)
 			local v = (c == 'x') and random(0, 0xf) or random(8, 0xb)
 			return string.format('%x', v)
 		end)
-    until not mail.is_uuid_existing(candidate_uuid)
-    return candidate_uuid
 end