internal: remove sys package

This package is replaced by container/stub. Remove and replace it with unexported implementation for the upcoming test suite rewrite.

Signed-off-by: Ophestra <cat@gensokyo.uk>

internal/app/paths.go

@@ -0,0 +1,36 @@
+package app
+
+import (
+	"strconv"
+
+	"hakurei.app/container"
+	"hakurei.app/hst"
+)
+
+// CopyPaths populates a [hst.Paths] struct.
+func CopyPaths(v *hst.Paths, userid int) { copyPaths(direct{}, v, userid) }
+
+// copyPaths populates a [hst.Paths] struct.
+func copyPaths(k syscallDispatcher, v *hst.Paths, userid int) {
+	const xdgRuntimeDir = "XDG_RUNTIME_DIR"
+
+	if tempDir, err := container.NewAbs(k.tempdir()); err != nil {
+		k.fatalf("invalid TMPDIR: %v", err)
+	} else {
+		v.TempDir = tempDir
+	}
+
+	v.SharePath = v.TempDir.Append("hakurei." + strconv.Itoa(userid))
+	k.verbosef("process share directory at %q", v.SharePath)
+
+	r, _ := k.lookupEnv(xdgRuntimeDir)
+	if a, err := container.NewAbs(r); err != nil {
+		// fall back to path in share since hakurei has no hard XDG dependency
+		v.RunDirPath = v.SharePath.Append("run")
+		v.RuntimePath = v.RunDirPath.Append("compat")
+	} else {
+		v.RuntimePath = a
+		v.RunDirPath = v.RuntimePath.Append("hakurei")
+	}
+	k.verbosef("runtime directory at %q", v.RunDirPath)
+}