From a67c2d33e50a9d154ecf5fef1463279716bba5d6 Mon Sep 17 00:00:00 2001 From: Matthew Wild Date: Wed, 3 Jun 2015 15:51:07 +0100 Subject: util.queue: Allow optional wrap-around when pushing, overwriting oldest unread item --- util/queue.lua | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'util/queue.lua') diff --git a/util/queue.lua b/util/queue.lua index afdcaf45..203da0e3 100644 --- a/util/queue.lua +++ b/util/queue.lua @@ -11,7 +11,7 @@ local have_utable, utable = pcall(require, "util.table"); -- For pre-allocation of table -local function new(size) +local function new(size, allow_wrapping) -- Head is next insert, tail is next read local head, tail = 1, 1; local items = 0; -- Number of stored items @@ -22,7 +22,12 @@ local function new(size) count = function (self) return items; end; push = function (self, item) if items >= size then - return nil, "queue full"; + if allow_wrapping then + tail = (tail%size)+1; -- Advance to next oldest item + items = items - 1; + else + return nil, "queue full"; + end end t[head] = item; items = items + 1; -- cgit v1.2.3