[antlir] Add standard uidmaps

Summary: Adding lists of known UIDs and GIDs. Each file represents a logical namespace (e.g. instagram, wsl, metalos). All UIDs/GIDs should be unique within a namespace. Code is extracted from D66000745, see that diff for more context.

Test Plan: used in next diffs

Reviewed By: epilatow

Differential Revision: D66301414

fbshipit-source-id: c68fcfb67acb91de091b72c58dea4e4d0cb42baf

antlir/uidmaps/BUCK

@@ -0,0 +1,24 @@
+load("@prelude//:paths.bzl", "paths")
+load("//antlir/bzl:build_defs.bzl", "alias", "export_file", "internal_external")
+# @oss-disable
+
+oncall("antlir")
+
+alias(
+    name = "default",
+    actual = internal_external(
+        fb = ":metalos",
+        oss = ":antlir",
+    ),
+    visibility = ["PUBLIC"],
+)
+
+[
+    export_file(
+        name = paths.basename(f).removesuffix(".json"),
+        src = f,
+    )
+    for f in glob(["**/*.json"])
+]
+
+# @oss-disable

antlir/uidmaps/antlir.json

@@ -0,0 +1,24 @@
+{
+    "users": {
+        "antlir": {
+            "uid": 1000
+        },
+        "foouser": {
+            "uid": 1001
+        },
+        "demoservice": {
+            "uid": 1002
+        }
+    },
+    "groups": {
+        "antlir": {
+            "gid": 1000
+        },
+        "foogroup": {
+            "gid": 1001
+        },
+        "demoservice": {
+            "gid": 1002
+        }
+    }
+}

antlir/uidmaps/centos.json

@@ -0,0 +1,10 @@
+{
+    "users": {
+        "systemd-network": {"uid": 192},
+        "systemd-resolve": {"uid": 193}
+    },
+    "groups": {
+        "systemd-network": {"gid": 192},
+        "systemd-resolve": {"gid": 193}
+    }
+}