1 files changed, 55 insertions, 0 deletions
diff --git a/src/file_path.ml b/src/file_path.ml
new file mode 100644
index 0000000..ea3068c
--- /dev/null
+++ b/src/file_path.ml
@@ -0,0 +1,55 @@
+type opts = {
+  must_be_file : bool;
+  parent : string option;
+  lookup_path : string option;
+  strict : bool; 
+}
+
+let default_opts = {
+  must_be_file = true;
+  parent = None;
+  lookup_path = None;
+  strict = false
+}
+
+let opts = ref default_opts
+
+let path_arg = ref ""
+
+let args = [
+    ("--file", Arg.Unit (fun () -> opts := {!opts with must_be_file=true}), "Path must point to a file and not a directory (default)");
+    ("--directory", Arg.Unit (fun () -> opts := {!opts with must_be_file=false}), "Path must point to a directory");
+    ("--parent-dir", Arg.String (fun s -> opts := {!opts with parent=(Some s)}), "Path must be inside specific parent directory");
+    ("--lookup-path", Arg.String (fun s -> opts := {!opts with lookup_path=(Some s)}), "Prefix path argument with lookup path");
+    ("--strict", Arg.Unit (fun () -> opts := {!opts with strict=true}), "Treat warnings as errors");
+]
+let usage = Printf.sprintf "Usage: %s [OPTIONS] <path>" Sys.argv.(0)
+
+let () = if Array.length Sys.argv = 1 then (Arg.usage args usage; exit 1)
+let () = Arg.parse args (fun s -> path_arg := s) usage
+
+let fail msg =
+  let () = print_endline msg in
+  exit 1
+
+let () =
+  let opts = !opts in
+  let path =
+    match opts.lookup_path with
+    | None -> !path_arg
+    | Some lookup_path -> FilePath.concat lookup_path !path_arg
+  in
+  (* First, check if the file/dir path exists at all. *)
+  let exists = FileUtil.test FileUtil.Exists path in
+  if not exists then Printf.ksprintf fail {|Incorrect path %s: no such file or directory|} path else
+  (* If yes, check if it's of the correct type: file or directory. *)
+  let is_file =	FileUtil.test FileUtil.Is_file path in
+  if ((not is_file) && opts.must_be_file) then Printf.ksprintf fail {|%s is a directory, not a file|} path else 
+  if (is_file && (not opts.must_be_file)) then Printf.ksprintf fail {|%s is a file, not a directory|} path else
+  match opts.parent with
+  | None ->
+    exit 0
+  | Some parent ->
+    if not (FilePath.is_subdir (FilePath.reduce path) (FilePath.reduce parent)) then
+    let msg = Printf.sprintf {|Path %s is not under %s directory|} path parent in
+    if opts.strict then fail msg else Printf.printf "Warning: %s\n" msg