Memory: new argument to scale usage units

Fixes #624

4 files changed, 33 insertions, 15 deletions

diff --git a/changelog.md b/changelog.md
index 102fedb..ebf7941 100644
--- a/changelog.md
+++ b/changelog.md
@@ -4,6 +4,7 @@ _New features_
 
   - New monitor `Load` providing load averages (stolen from Finn
     Lawler, with FreeBSD support thanks to Michał Zielonka).
+  - New argument `scale` for `Memory` monitor to scale size units.
 
 _Bug fixes_
 
diff --git a/doc/plugins.org b/doc/plugins.org
index 8ff75e4..383207c 100644
--- a/doc/plugins.org
+++ b/doc/plugins.org
@@ -510,6 +510,10 @@
           =freeipat=.
         - =--available-icon-pattern=: dynamic string for available memory
           ratio in =availableipat=.
+        - =--scale=: sizes (total, free, etc.) are reported in units of
+          ~Mb/scale~, with scale defaulting to 1.0.  So, for
+          instance, to get sizes reported in Gb, set this parameter
+          to 1024.
 
       - Thresholds refer to percentage of used memory
       - Variables that can be used with the =-t/--template= argument:
@@ -517,8 +521,18 @@
         =usedbar=, =usedvbar=, =usedipat=, =freeratio=, =freebar=, =freevbar=,
         =freeipat=, =availableratio=, =availablebar=, =availablevbar=,
         =availableipat=
+
       - Default template: =Mem: <usedratio>% (<cache>M)=
 
+      - Examples:
+
+        #+begin_src haskell
+          -- A monitor reporting memory used in Gb
+          Memory [ "-t", "<used> Gb", "--", "--scale", "1024"] 20
+          -- As above, but using one decimal digit to print numbers
+          Memory [ "-t", "<used> Gb", "-d", "1", "--", "--scale", "1024"] 20
+        #+end_src
+
 ***** =Swap Args RefreshRate=
 
       - Aliases to =swap=
diff --git a/src/Xmobar/Plugins/Monitors/Mem.hs b/src/Xmobar/Plugins/Monitors/Mem.hs
index 6a863ce..d55ac2b 100644
--- a/src/Xmobar/Plugins/Monitors/Mem.hs
+++ b/src/Xmobar/Plugins/Monitors/Mem.hs
@@ -13,7 +13,7 @@
 --
 -----------------------------------------------------------------------------
 
-module Xmobar.Plugins.Monitors.Mem (memConfig, runMem, totalMem, usedMem) where
+module Xmobar.Plugins.Monitors.Mem (memConfig, runMem) where
 
 import Xmobar.Plugins.Monitors.Common
 import System.Console.GetOpt
@@ -29,6 +29,7 @@ data MemOpts = MemOpts
   { usedIconPattern :: Maybe IconPattern
   , freeIconPattern :: Maybe IconPattern
   , availableIconPattern :: Maybe IconPattern
+  , scale :: Float
   }
 
 defaultOpts :: MemOpts
@@ -36,6 +37,7 @@ defaultOpts = MemOpts
   { usedIconPattern = Nothing
   , freeIconPattern = Nothing
   , availableIconPattern = Nothing
+  , scale = 1.0
   }
 
 options :: [OptDescr (MemOpts -> MemOpts)]
@@ -46,31 +48,29 @@ options =
      o { freeIconPattern = Just $ parseIconPattern x }) "") ""
   , Option "" ["available-icon-pattern"] (ReqArg (\x o ->
      o { availableIconPattern = Just $ parseIconPattern x }) "") ""
+  , Option "" ["scale"] (ReqArg (\x o -> o { scale = read x }) "") ""
   ]
 
 memConfig :: IO MConfig
 memConfig = mkMConfig
-       "Mem: <usedratio>% (<cache>M)" -- template
+       "Mem: <usedratio>% (<cache>M)"
        ["usedbar", "usedvbar", "usedipat", "freebar", "freevbar", "freeipat",
         "availablebar", "availablevbar", "availableipat",
         "usedratio", "freeratio", "availableratio",
-        "total", "free", "buffer", "cache", "available", "used"] -- available replacements
-
-totalMem :: IO Float
-totalMem = fmap ((*1024) . (!!1)) MM.parseMEM
-
-usedMem :: IO Float
-usedMem = fmap ((*1024) . (!!6)) MM.parseMEM
+        "total", "free", "buffer", "cache", "available", "used"]
 
 formatMem :: MemOpts -> [Float] -> Monitor [String]
 formatMem opts (r:fr:ar:xs) =
-    do let f = showDigits 0
-           mon i x = [showPercentBar (100 * x) x, showVerticalBar (100 * x) x, showIconPattern i x]
+    do d <- getConfigValue decDigits
+       let f = showDigits d
+           mon i x = [ showPercentBar (100 * x) x
+                     , showVerticalBar (100 * x) x
+                     , showIconPattern i x]
        sequence $ mon (usedIconPattern opts) r
            ++ mon (freeIconPattern opts) fr
            ++ mon (availableIconPattern opts) ar
            ++ map showPercentWithColors [r, fr, ar]
-           ++ map (showWithColors f) xs
+           ++ map (showWithColors f . (/ scale opts)) xs
 formatMem _ _ = replicate 10 `fmap` getConfigValue naString
 
 runMem :: [String] -> Monitor String
diff --git a/src/Xmobar/Plugins/Monitors/Mem/Linux.hs b/src/Xmobar/Plugins/Monitors/Mem/Linux.hs
index 9e48d22..79dcc9d 100644
--- a/src/Xmobar/Plugins/Monitors/Mem/Linux.hs
+++ b/src/Xmobar/Plugins/Monitors/Mem/Linux.hs
@@ -23,11 +23,14 @@ parseMEM :: IO [Float]
 parseMEM =
     do file <- fileMEM
        let content = map words $ take 8 $ lines file
-           info = M.fromList $ map (\line -> (head line, (read $ line !! 1 :: Float) / 1024)) content
-           [total, free, buffer, cache] = map (info M.!) ["MemTotal:", "MemFree:", "Buffers:", "Cached:"]
+           info = M.fromList $ map (
+             \line -> (head line, (read $ line !! 1 :: Float) / 1024)) content
+           [total, free, buffer, cache] =
+             map (info M.!) ["MemTotal:", "MemFree:", "Buffers:", "Cached:"]
            available = M.findWithDefault (free + buffer + cache) "MemAvailable:" info
            used = total - available
            usedratio = used / total
            freeratio = free / total
            availableratio = available / total
-       return [usedratio, freeratio, availableratio, total, free, buffer, cache, available, used]
+       return [ usedratio, freeratio, availableratio
+              , total, free, buffer, cache, available, used]