mem: rewrite and simplify

mem.lua

@@ -8,7 +8,7 @@
 local io = { open = io.open }
 local setmetatable = setmetatable
 local math = { floor = math.floor }
-local string = { match = string.match }
+local string = { gmatch = string.gmatch }
 -- }}}
 
 
@@ -23,33 +23,28 @@ local function worker(format)
     local mem = { buf = {}, swp = {} }
 
     for line in f:lines() do
-        if string.match(line, "^MemTotal.*") then
-            mem.total = math.floor(string.match(line, "([%d]+)")/1024)
-        elseif string.match(line, "^MemFree.*") then
-            mem.buf.f = math.floor(string.match(line, "([%d]+)")/1024)
-        elseif string.match(line, "^Buffers.*") then
-            mem.buf.b = math.floor(string.match(line, "([%d]+)")/1024)
-        elseif string.match(line, "^Cached.*") then
-            mem.buf.c = math.floor(string.match(line, "([%d]+)")/1024)
-        -- Get swap stats while we are at it
-        elseif string.match(line, "^SwapTotal.*") then
-            mem.swp.total = math.floor(string.match(line, "([%d]+)")/1024)
-        elseif string.match(line, "^SwapFree.*") then
-            mem.swp.free = math.floor(string.match(line, "([%d]+)")/1024)
+        for k, v in string.gmatch(line, "([%a]+):[%s]+([%d]+).+") do
+            if     k == "MemTotal"  then mem.total = math.floor(v/1024)
+            elseif k == "MemFree"   then mem.buf.f = math.floor(v/1024)
+            elseif k == "Buffers"   then mem.buf.b = math.floor(v/1024)
+            elseif k == "Cached"    then mem.buf.c = math.floor(v/1024)
+            elseif k == "SwapTotal" then mem.swp.t = math.floor(v/1024)
+            elseif k == "SwapFree"  then mem.swp.f = math.floor(v/1024)
+            end
         end
     end
     f:close()
 
-    -- Calculate percentage
+    -- Calculate memory percentage
     mem.free  = mem.buf.f + mem.buf.b + mem.buf.c
     mem.inuse = mem.total - mem.free
     mem.usep  = math.floor(mem.inuse / mem.total * 100)
     -- Calculate swap percentage
-    mem.swp.inuse = mem.swp.total - mem.swp.free
-    mem.swp.usep  = math.floor(mem.swp.inuse / mem.swp.total * 100)
+    mem.swp.inuse = mem.swp.t - mem.swp.f
+    mem.swp.usep  = math.floor(mem.swp.inuse / mem.swp.t * 100)
 
     return {mem.usep,     mem.inuse,     mem.total, mem.free,
-            mem.swp.usep, mem.swp.inuse, mem.swp.total, mem.swp.free}
+            mem.swp.usep, mem.swp.inuse, mem.swp.t, mem.swp.f}
 end
 -- }}}