Merge branch 'bjorn/stdlib/erl_tar/OTP-11854' into maint

* bjorn/stdlib/erl_tar/OTP-11854:
  Correct typo in type specification
  Fix typo in erl_tar docs
  Update information about compatibility
  Correct end of tape marker
  Support path names with characters outside the US ASCII range

3 files changed, 118 insertions, 13 deletions

diff --git a/lib/stdlib/doc/src/erl_tar.xml b/lib/stdlib/doc/src/erl_tar.xml
index f81e36f810..7f25f5b7bc 100644
--- a/lib/stdlib/doc/src/erl_tar.xml
+++ b/lib/stdlib/doc/src/erl_tar.xml
@@ -35,10 +35,11 @@
   <modulesummary>Unix 'tar' utility for reading and writing tar archives</modulesummary>
   <description>
     <p>The <c>erl_tar</c> module archives and extract files to and from
-      a tar file. The tar file format is the POSIX extended tar file format
-      specified in IEEE Std 1003.1 and ISO/IEC&nbsp;9945-1. That is the same
-      format as used by <c>tar</c> program on Solaris, but is not the same
-      as used by the GNU tar program.</p>
+      a tar file. <c>erl_tar</c> supports the <c>ustar</c> format
+      (IEEE Std 1003.1 and ISO/IEC&nbsp;9945-1). All modern <c>tar</c>
+      programs (including GNU tar) can read this format. To ensure that
+      that GNU tar produces a tar file that <c>erl_tar</c> can read,
+      give the <c>--format=ustar</c> option to GNU tar.</p>
     <p>By convention, the name of a tar file should end in "<c>.tar</c>".
       To abide to the convention, you'll need to add "<c>.tar</c>" yourself
       to the name.</p>
@@ -65,6 +66,20 @@
   </description>
 
   <section>
+    <title>UNICODE SUPPORT</title>
+    <p>If <seealso
+    marker="kernel:file#native_name_encoding/0">file:native_name_encoding/0</seealso>
+    returns <c>utf8</c>, path names will be encoded in UTF-8 when
+    creating tar files and path names will be assumed to be encoded in
+    UTF-8 when extracting tar files.</p>
+
+    <p>If <seealso
+    marker="kernel:file#native_name_encoding/0">file:native_name_encoding/0</seealso>
+    returns <c>latin1</c>, no translation of path names will be
+    done.</p>
+  </section>
+
+  <section>
     <title>LIMITATIONS</title>
     <p>For maximum compatibility, it is safe to archive files with names
       up to 100 characters in length. Such tar files can generally be
@@ -112,8 +127,8 @@
       <fsummary>Add a file to an open tar file</fsummary>
       <type>
         <v>TarDescriptor = term()</v>
-        <v>FilenameOrBin = Filename()|binary()</v>
-        <v>Filename = filename()()</v>
+        <v>FilenameOrBin = filename()|binary()</v>
+        <v>Filename = filename()</v>
         <v>NameInArchive = filename()</v>
         <v>Options = [Option]</v>
         <v>Option = dereference|verbose</v>
diff --git a/lib/stdlib/src/erl_tar.erl b/lib/stdlib/src/erl_tar.erl
index 40b48d7999..acf7a5cd40 100644
--- a/lib/stdlib/src/erl_tar.erl
+++ b/lib/stdlib/src/erl_tar.erl
@@ -381,7 +381,12 @@ to_octal(Int, Count, Result) ->
     to_octal(Int div 8, Count-1, [Int rem 8 + $0|Result]).
 
 to_string(Str0, Count) ->
-    Str = list_to_binary(Str0),
+    Str = case file:native_name_encoding() of
+	      utf8 ->
+		  unicode:characters_to_binary(Str0);
+	      latin1 ->
+		  list_to_binary(Str0)
+	  end,
     case byte_size(Str) of
 	Size when Size < Count ->
 	    [Str|zeroes(Count-Size)];
@@ -392,9 +397,17 @@ to_string(Str0, Count) ->
 
 pad_file(File) ->
     {ok,Position} = file:position(File, {cur,0}),
-    %% There must be at least one empty record at the end of the file.
-    Zeros = zeroes(?block_size - (Position rem ?block_size)),
-    file:write(File, Zeros).
+    %% There must be at least two zero records at the end.
+    Fill = case ?block_size - (Position rem ?block_size) of
+	       Fill0 when Fill0 < 2*?record_size ->
+		   %% We need to another block here to ensure that there
+		   %% are at least two zero records at the end.
+		   Fill0 + ?block_size;
+	       Fill0 ->
+		   %% Large enough.
+		   Fill0
+	   end,
+    file:write(File, zeroes(Fill)).
 
 split_filename(Name) when length(Name) =< ?th_name_len ->
     {"", Name};
@@ -608,7 +621,22 @@ typeflag(Bin) ->
 %% Get the name of the file from the prefix and name fields of the
 %% tar header.
 
-get_name(Bin) ->
+get_name(Bin0) ->
+    List0 = get_name_raw(Bin0),
+    case file:native_name_encoding() of
+	utf8 ->
+	    Bin = list_to_binary(List0),
+	    case unicode:characters_to_list(Bin) of
+		{error,_,_} ->
+		    List0;
+		List when is_list(List) ->
+		    List
+	    end;
+	latin1 ->
+	    List0
+    end.
+
+get_name_raw(Bin) ->
     Name = from_string(Bin, ?th_name, ?th_name_len),
     case binary_to_list(Bin, ?th_prefix+1, ?th_prefix+1) of
 	[0] ->
diff --git a/lib/stdlib/test/tar_SUITE.erl b/lib/stdlib/test/tar_SUITE.erl
index 5bc34e35af..6349139925 100644
--- a/lib/stdlib/test/tar_SUITE.erl
+++ b/lib/stdlib/test/tar_SUITE.erl
@@ -23,7 +23,7 @@
 	 create_long_names/1, bad_tar/1, errors/1, extract_from_binary/1,
 	 extract_from_binary_compressed/1,
 	 extract_from_open_file/1, symlinks/1, open_add_close/1, cooked_compressed/1,
-	 memory/1]).
+	 memory/1,unicode/1]).
 
 -include_lib("test_server/include/test_server.hrl").
 -include_lib("kernel/include/file.hrl").
@@ -34,7 +34,7 @@ all() ->
     [borderline, atomic, long_names, create_long_names,
      bad_tar, errors, extract_from_binary,
      extract_from_binary_compressed, extract_from_open_file,
-     symlinks, open_add_close, cooked_compressed, memory].
+     symlinks, open_add_close, cooked_compressed, memory, unicode].
 
 groups() -> 
     [].
@@ -73,6 +73,7 @@ borderline(Config) when is_list(Config) ->
 
     ?line lists:foreach(fun(Size) -> borderline_test(Size, TempDir) end,
 			[0, 1, 10, 13, 127, 333, Record-1, Record, Record+1,
+			 Block-2*Record-1, Block-2*Record, Block-2*Record+1,
 			 Block-Record-1, Block-Record, Block-Record+1,
 			 Block-1, Block, Block+1,
 			 Block+Record-1, Block+Record, Block+Record+1]),
@@ -726,6 +727,56 @@ memory(Config) when is_list(Config) ->
     ?line ok = delete_files([Name1,Name2]),
     ok.
 
+%% Test filenames with characters outside the US ASCII range.
+unicode(Config) when is_list(Config) ->
+    PrivDir = ?config(priv_dir, Config),
+    do_unicode(PrivDir),
+    case has_transparent_naming() of
+	true ->
+	    Pa = filename:dirname(code:which(?MODULE)),
+	    Node = start_node(unicode, "+fnl -pa "++Pa),
+	    ok = rpc:call(Node, erlang, apply,
+			  [fun() -> do_unicode(PrivDir) end,[]]),
+	    true = test_server:stop_node(Node),
+	    ok;
+	false ->
+	    ok
+    end.
+
+has_transparent_naming() ->
+    case os:type() of
+	{unix,darwin} -> false;
+	{unix,_} -> true;
+	_ -> false
+    end.
+
+do_unicode(PrivDir) ->
+    ok = file:set_cwd(PrivDir),
+    ok = file:make_dir("unicöde"),
+
+    Names = unicode_create_files(),
+    Tar = "unicöde.tar",
+    ok = erl_tar:create(Tar, ["unicöde"], []),
+    {ok,Names} = erl_tar:table(Tar, []),
+    _ = [ok = file:delete(Name) || Name <- Names],
+    ok = erl_tar:extract(Tar),
+    _ = [{ok,_} = file:read_file(Name) || Name <- Names],
+    _ = [ok = file:delete(Name) || Name <- Names],
+    ok = file:del_dir("unicöde"),
+    ok.
+
+unicode_create_files() ->
+    FileA = "unicöde/smörgåsbord",
+    ok = file:write_file(FileA, "yum!\n"),
+    [FileA|case file:native_name_encoding() of
+	       utf8 ->
+		   FileB = "unicöde/Хороший файл!",
+		   ok = file:write_file(FileB, "But almost empty.\n"),
+		   [FileB];
+	       latin1 ->
+		   []
+	   end].
+
 %% Delete the given list of files.
 delete_files([]) -> ok;
 delete_files([Item|Rest]) ->
@@ -791,3 +842,14 @@ make_temp_dir(Base, I) ->
 	ok -> Name;
 	{error,eexist} -> make_temp_dir(Base, I+1)
     end.
+
+start_node(Name, Args) ->
+    [_,Host] = string:tokens(atom_to_list(node()), "@"),
+    ct:log("Trying to start ~w@~s~n", [Name,Host]),
+    case test_server:start_node(Name, peer, [{args,Args}]) of
+	{error,Reason} ->
+	    test_server:fail(Reason);
+	{ok,Node} ->
+	    ct:log("Node ~p started~n", [Node]),
+	    Node
+    end.