feat: add the disks and cache samplers

1 files changed, 33 insertions, 0 deletions

diff --git a/bin/cache-sample.sh b/bin/cache-sample.sh
new file mode 100755
index 0000000..cac8911
--- /dev/null
+++ b/bin/cache-sample.sh
@@ -0,0 +1,33 @@
+#!/bin/bash
+# Sample ~/.cache sizes into a cache file, for widgets/cache.lua.
+#
+# du walks the tree and costs about 100ms warm, which is fine every 15 minutes
+# and unthinkable on a 2-second draw. The old conky config used the same
+# interval for the same reason.
+
+set -u
+
+CACHE_DIR="${XDG_CACHE_HOME:-$HOME/.cache}/udt"
+CACHE="$CACHE_DIR/cachesize.txt"
+TARGET="${XDG_CACHE_HOME:-$HOME/.cache}"
+
+mkdir -p "$CACHE_DIR"
+
+TMP="$CACHE.tmp.$$"
+trap 'rm -f "$TMP"' EXIT
+umask 077
+
+# Total first, then the four largest children. `sort -h` compares human sizes
+# numerically; the Lua side converts them again because it needs the ratio to
+# the total, not just the order.
+{
+    du -sh "$TARGET" 2>/dev/null
+    du -sh "$TARGET"/* 2>/dev/null | sort -hr | head -4
+} > "$TMP"
+
+if [ ! -s "$TMP" ]; then
+    echo "cache-sample: du produced nothing" >&2
+    exit 1
+fi
+
+mv -f "$TMP" "$CACHE"