1 files changed, 103 insertions, 0 deletions
diff --git a/nix/buildManPages/default.nix b/nix/buildManPages/default.nix
new file mode 100644
index 000000000000..746ed25182b4
--- /dev/null
+++ b/nix/buildManPages/default.nix
@@ -0,0 +1,103 @@
+{ depot, pkgs, lib, ... }:
+
+let
+  inherit (pkgs)
+    gzip
+    mandoc
+    coreutils
+    ;
+
+  inherit (depot.nix)
+    runExecline
+    getBins
+    ;
+
+  bins = getBins mandoc [ "mandoc" ]
+    // getBins gzip [ "gzip" ]
+    // getBins coreutils [ "mkdir" "ln" "cp" ]
+  ;
+
+  defaultGzip = true;
+
+  basename = gzip: { name, section, ... }:
+    "${name}.${toString section}${lib.optionalString gzip ".gz"}";
+
+  manDir = { section, ... }:
+    "\${out}/share/man/man${toString section}";
+
+  target = gzip: args:
+    "${manDir args}/${basename gzip args}";
+
+  buildManPage =
+    { requireLint ? false
+    , gzip ? defaultGzip
+    , ...
+    }:
+    { content
+    , ...
+    }@page:
+    let
+      source = builtins.toFile (basename false page) content;
+    in
+    runExecline (basename gzip page) { } ([
+      (if requireLint then "if" else "foreground")
+      [
+        bins.mandoc
+        "-mdoc"
+        "-T"
+        "lint"
+        source
+      ]
+      "importas"
+      "out"
+      "out"
+    ] ++ (if gzip then [
+      "redirfd"
+      "-w"
+      "1"
+      "$out"
+      bins.gzip
+      "-c"
+      source
+    ] else [
+      bins.cp
+      "--reflink=auto"
+      source
+      "$out"
+    ]));
+
+  buildManPages =
+    name:
+    { derivationArgs ? { }
+    , gzip ? defaultGzip
+    , ...
+    }@args:
+    pages:
+    runExecline "${name}-man-pages"
+      {
+        inherit derivationArgs;
+      }
+      ([
+        "importas"
+        "out"
+        "out"
+      ] ++ lib.concatMap
+        ({ name, section, content }@page: [
+          "if"
+          [ bins.mkdir "-p" (manDir page) ]
+          "if"
+          [
+            bins.ln
+            "-s"
+            (buildManPage args page)
+            (target gzip page)
+          ]
+        ])
+        pages);
+
+in
+{
+  __functor = _: buildManPages;
+
+  single = buildManPage;
+}