i3/conky: Autodetect CPU load and temperature.

Device ordering is something that can vastly differ from system to
system, so we're detecting the available CPUs on conky startup and pass
the corresponding hwmon/cpu expressions to -t.

Signed-off-by: aszlig <aszlig@redmoonstudios.org>

1 files changed, 27 insertions, 24 deletions

diff --git a/modules/i3/conky.nix b/modules/i3/conky.nix
index 9463ae32..baee9c6f 100644
--- a/modules/i3/conky.nix
+++ b/modules/i3/conky.nix
@@ -3,7 +3,7 @@
 with pkgs.lib;
 
 let
-  mkConfig = text: pkgs.writeText "conkyrc" ''
+  baseConfig = pkgs.writeText "conkyrc" ''
     cpu_avg_samples 2
     net_avg_samples 2
     no_buffers yes
@@ -17,27 +17,12 @@ let
     pad_percents 3
     use_spacer left
     TEXT
-    ${text}
   '';
 
-  cexpr = name: args: "\${${name} ${concatStringsSep " " args}}";
+  cexpr = name: args: "\\\${${name} ${concatStringsSep " " args}}";
 
   primaryNetInterface = "enp0s25";
 
-  mkCpuLoad = threads: let
-    mkThread = thread: (cexpr "cpu" [ "cpu${toString thread}" ]) + "%";
-    loads = map mkThread (range 1 threads);
-  in concatStringsSep " " loads;
-
-  mkCpuTemp = cores: let
-    mkCore = core: (cexpr "platform" [
-      "coretemp.0"
-      "temp"
-      "${toString (core + 1)}"
-    ]) + "C";
-    temps = map mkCore (range 1 cores);
-  in concatStringsSep " " temps;
-
   mkNetInfo = iface: let
     upspeed = cexpr "upspeed" [ iface ];
     downspeed = cexpr "downspeed" [ iface ];
@@ -62,23 +47,41 @@ let
     conky = pkgs.conky.override {
       weatherMetar = true;
     };
-    cfg = mkConfig text;
   in pkgs.writeScript "conky-run.sh" ''
     #!${pkgs.stdenv.shell}
-    ${conky}/bin/conky -c "${cfg}"
+    PATH="${pkgs.coreutils}/bin"
+    cpuload() {
+      for i in $(seq 1 $(nproc))
+      do
+        [ $i -eq 1 ] || echo -n ' '
+        echo -n "\''${cpu cpu$i}%"
+      done
+    }
+    cputemp_collect() {
+      for i in /sys/bus/platform/devices/coretemp.?/hwmon/hwmon?/temp?_input
+      do
+        [ -e "$i" ] || continue
+        echo "$i" | ${pkgs.gnused}/bin/sed -re \
+          's/^.*hwmon([0-9]+)[^0-9]*([0-9]+).*$/''${hwmon \1 temp \2}/'
+      done
+    }
+    cputemp() {
+      echo $(cputemp_collect)
+    }
+    ${conky}/bin/conky -c "${baseConfig}" -t "${text}"
   '';
 
 in {
   left = mkConky [
-    "CPU: ${mkCpuLoad 8} - ${cexpr "cpu" [ "cpu0" ]}%"
-    "MEM: $mem/$memmax - $memperc%"
-    "SWAP: $swap/$swapmax $swapperc%"
+    "CPU: $(cpuload) - ${cexpr "cpu" [ "cpu0" ]}%"
+    "MEM: \\$mem/\\$memmax - \\$memperc%"
+    "SWAP: \\$swap/\\$swapmax \\$swapperc%"
   ];
 
   right = mkConky [
     "NET: ${mkNetInfo primaryNetInterface}"
     "DF: ${mkDiskFree "/"}"
-    "LAVG: $loadavg"
-    "TEMP - CPU: ${mkCpuTemp 4} - GPU: ${gpuTemp} - OUTSIDE: ${weather}"
+    "LAVG: \\$loadavg"
+    "TEMP - CPU: $(cputemp) - GPU: ${gpuTemp} - OUTSIDE: ${weather}"
   ];
 }