[Libguestfs] [PATCH v8 1/4] mllib: add subdirectory function to common_utils

Signed-off-by: Tomáš Golembiovský <tgolembi(a)redhat.com&gt; --- mllib/common_utils.ml | 9 +++++++++ mllib/common_utils.mli | 10 ++++++++++ mllib/common_utils_tests.ml | 7 +++++++ 3 files changed, 26 insertions(+) diff --git a/mllib/common_utils.ml b/mllib/common_utils.ml index e9ae6a4a2..a79abdd7e 100644 --- a/mllib/common_utils.ml +++ b/mllib/common_utils.ml @@ -236,6 +236,15 @@ end let (//) = Filename.concat let quote = Filename.quote +let subdirectory parent path = + if path = parent then + "" + else if String.is_prefix path (parent // "") then + let len = String.length parent in + String.sub path (len+1) (String.length path - len-1) + else + raise (Invalid_argument (sprintf "%S is not a path prefix of %S" parent path)) + let ( +^ ) = Int64.add let ( -^ ) = Int64.sub let ( *^ ) = Int64.mul diff --git a/mllib/common_utils.mli b/mllib/common_utils.mli index 722e528e5..977ce6576 100644 --- a/mllib/common_utils.mli +++ b/mllib/common_utils.mli @@ -116,6 +116,16 @@ val ( // ) : string -> string -> string val quote : string -> string (** Shell-safe quoting of a string (alias for {!Filename.quote}). *) +val subdirectory : string -> string -> string +(** [subdirectory parent path] returns subdirectory part of [path] relative + to the [parent]. If [path] and [parent] point to the same directory empty + string is returned. + + Note: path normalization on arguments is NOT performed! + + If [parent] is not a path prefix of [path] the function raises + [Invalid_argument]. *) + val ( +^ ) : int64 -> int64 -> int64 val ( -^ ) : int64 -> int64 -> int64 val ( *^ ) : int64 -> int64 -> int64 diff --git a/mllib/common_utils_tests.ml b/mllib/common_utils_tests.ml index 77b0524c1..aacc01e04 100644 --- a/mllib/common_utils_tests.ml +++ b/mllib/common_utils_tests.ml @@ -27,6 +27,12 @@ let assert_equal_int = assert_equal ~printer:(fun x -> string_of_int x) let assert_equal_int64 = assert_equal ~printer:(fun x -> Int64.to_string x) let assert_equal_stringlist = assert_equal ~printer:(fun x -> "(" ^ (String.escaped (String.concat "," x)) ^ ")") +let test_subdirectory ctx = + assert_equal_string "" (subdirectory "/foo" "/foo"); + assert_equal_string "" (subdirectory "/foo" "/foo/"); + assert_equal_string "bar" (subdirectory "/foo" "/foo/bar"); + assert_equal_string "bar/baz" (subdirectory "/foo" "/foo/bar/baz") + (* Test Common_utils.int_of_le32 and Common_utils.le32_of_int. *) let test_le32 ctx = assert_equal_int64 0x20406080L (int_of_le32 "\x80\x60\x40\x20"); @@ -129,6 +135,7 @@ let test_string_lines_split ctx = let suite = "mllib Common_utils" >::: [ + "subdirectory" >:: test_subdirectory; "numeric.le32" >:: test_le32; "sizes.parse_resize" >:: test_parse_resize; "sizes.human_size" >:: test_human_size; -- 2.11.0