feat: add a module (radix scripts memory) to gather memory usage information

modules/radix/utils/memory.scm

@@ -0,0 +1,35 @@
+(define-module (radix utils memory)
+  #:use-module (srfi srfi-26)
+  #:use-module (ice-9 rdelim)
+  #:export (current-memory-info
+            current-ram-usage
+            current-swap-usage))
+
+(define (current-memory-info)
+  (let* ((port (open "/proc/meminfo" O_RDONLY))
+         (lines (let loop ((line (read-line port))
+                           (acc '()))
+                  (if (eof-object? line) acc
+                    (loop (read-line port)
+                          (cons line acc))))))
+    (close-input-port port)
+    (map (compose
+           (lambda (line)
+             (cons (car line)
+                   ((compose (cut round/ <> 1024)
+                             string->number
+                             car
+                             (cut string-split <> #\ )
+                             string-trim
+                             cadr)
+                     line)))
+           (cut string-split <> #\:))
+         lines)))
+
+(define (current-ram-usage)
+  (apply - (map (cut assoc-ref (current-memory-info) <>)
+                '("MemTotal" "MemFree" "Buffers" "Cached" "SReclaimable"))))
+
+(define (current-swap-usage)
+  (apply - (map (cut assoc-ref (current-memory-info) <>)
+                '("SwapTotal" "SwapFree"))))