feat: add unified microvm & container definition; add net, misc, disko lib extension

lib/misc.nix

@@ -0,0 +1,84 @@
+_inputs: _final: prev: let
+  inherit
+    (prev.lib)
+    filter
+    foldl'
+    genAttrs
+    genList
+    mergeAttrs
+    mkMerge
+    stringToCharacters
+    substring
+    unique
+    ;
+
+  # Counts how often each element occurrs in xs.
+  # Elements must be strings.
+  countOccurrences =
+    foldl'
+    (acc: x: acc // {${x} = (acc.${x} or 0) + 1;})
+    {};
+
+  # Returns all elements in xs that occur at least twice
+  duplicates = xs: let
+    occurrences = countOccurrences xs;
+  in
+    unique (filter (x: occurrences.${x} > 1) xs);
+
+  # Concatenates all given attrsets as if calling a // b in order.
+  concatAttrs = foldl' mergeAttrs {};
+
+  # True if the path or string starts with /
+  isAbsolutePath = x: substring 0 1 x == "/";
+
+  # Merges all given attributes from the given attrsets using mkMerge.
+  # Useful to merge several top-level configs in a module.
+  mergeToplevelConfigs = keys: attrs:
+    genAttrs keys (attr: mkMerge (map (x: x.${attr} or {}) attrs));
+
+  # Calculates base^exp, but careful, this overflows for results > 2^62
+  pow = base: exp: foldl' (a: x: x * a) 1 (genList (_: base) exp);
+
+  hexLiteralValues = {
+    "0" = 0;
+    "1" = 1;
+    "2" = 2;
+    "3" = 3;
+    "4" = 4;
+    "5" = 5;
+    "6" = 6;
+    "7" = 7;
+    "8" = 8;
+    "9" = 9;
+    "a" = 10;
+    "b" = 11;
+    "c" = 12;
+    "d" = 13;
+    "e" = 14;
+    "f" = 15;
+    "A" = 10;
+    "B" = 11;
+    "C" = 12;
+    "D" = 13;
+    "E" = 14;
+    "F" = 15;
+  };
+
+  # Converts the given hex string to an integer. Only reliable for inputs in [0, 2^63),
+  # after that the sign bit will overflow.
+  hexToDec = v: foldl' (acc: x: acc * 16 + hexLiteralValues.${x}) 0 (stringToCharacters v);
+in {
+  lib =
+    prev.lib
+    // {
+      inherit
+        concatAttrs
+        countOccurrences
+        duplicates
+        hexToDec
+        isAbsolutePath
+        mergeToplevelConfigs
+        pow
+        ;
+    };
+}