From bd3dc9ac24d76bbdc8ce973a739fd52b5caa63ff Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Eric=20Meadows-J=C3=B6nsson?=
 <eric.meadows.jonsson@gmail.com>
Date: Wed, 25 Oct 2017 21:12:21 +0200
Subject: Add options for creating reproducible tars

---
 lib/stdlib/src/erl_tar.erl | 72 +++++++++++++++++++++++++++++++++++-----------
 1 file changed, 56 insertions(+), 16 deletions(-)

(limited to 'lib/stdlib/src/erl_tar.erl')

diff --git a/lib/stdlib/src/erl_tar.erl b/lib/stdlib/src/erl_tar.erl
index 48bbd38f9b..b04cdb3609 100644
--- a/lib/stdlib/src/erl_tar.erl
+++ b/lib/stdlib/src/erl_tar.erl
@@ -1,7 +1,7 @@
 %%
 %% %CopyrightBegin%
 %%
-%% Copyright Ericsson AB 1997-2017. All Rights Reserved.
+%% Copyright Ericsson AB 1997-2018. All Rights Reserved.
 %%
 %% Licensed under the Apache License, Version 2.0 (the "License");
 %% you may not use this file except in compliance with the License.
@@ -457,26 +457,61 @@ add(Reader, NameOrBin, NameInArchive, Options)
 
 do_add(#reader{access=write}=Reader, Name, NameInArchive, Options)
   when is_list(NameInArchive), is_list(Options) ->
-    RF = fun(F) -> file:read_link_info(F, [{time, posix}]) end,
+    RF = apply_file_info_opts_fun(Options, read_link_info),
     Opts = #add_opts{read_info=RF},
-    add1(Reader, Name, NameInArchive, add_opts(Options, Opts));
+    add1(Reader, Name, NameInArchive, add_opts(Options, Options, Opts));
 do_add(#reader{access=read},_,_,_) ->
     {error, eacces};
 do_add(Reader,_,_,_) ->
     {error, {badarg, Reader}}.
 
-add_opts([dereference|T], Opts) ->
-    RF = fun(F) -> file:read_file_info(F, [{time, posix}]) end,
-    add_opts(T, Opts#add_opts{read_info=RF});
-add_opts([verbose|T], Opts) ->
-    add_opts(T, Opts#add_opts{verbose=true});
-add_opts([{chunks,N}|T], Opts) ->
-    add_opts(T, Opts#add_opts{chunk_size=N});
-add_opts([_|T], Opts) ->
-    add_opts(T, Opts);
-add_opts([], Opts) ->
+add_opts([dereference|T], AllOptions, Opts) ->
+    RF = apply_file_info_opts_fun(AllOptions, read_file_info),
+    add_opts(T, AllOptions, Opts#add_opts{read_info=RF});
+add_opts([verbose|T], AllOptions, Opts) ->
+    add_opts(T, AllOptions, Opts#add_opts{verbose=true});
+add_opts([{chunks,N}|T], AllOptions, Opts) ->
+    add_opts(T, AllOptions, Opts#add_opts{chunk_size=N});
+add_opts([{atime,Value}|T], AllOptions, Opts) ->
+    add_opts(T, AllOptions, Opts#add_opts{atime=Value});
+add_opts([{mtime,Value}|T], AllOptions, Opts) ->
+    add_opts(T, AllOptions, Opts#add_opts{mtime=Value});
+add_opts([{ctime,Value}|T], AllOptions, Opts) ->
+    add_opts(T, AllOptions, Opts#add_opts{ctime=Value});
+add_opts([{uid,Value}|T], AllOptions, Opts) ->
+    add_opts(T, AllOptions, Opts#add_opts{uid=Value});
+add_opts([{gid,Value}|T], AllOptions, Opts) ->
+    add_opts(T, AllOptions, Opts#add_opts{gid=Value});
+add_opts([_|T], AllOptions, Opts) ->
+    add_opts(T, AllOptions, Opts);
+add_opts([], _AllOptions, Opts) ->
     Opts.
 
+apply_file_info_opts(Opts, {ok, FileInfo}) ->
+    {ok, do_apply_file_info_opts(Opts, FileInfo)};
+apply_file_info_opts(_Opts, Other) ->
+    Other.
+
+do_apply_file_info_opts([{atime,Value}|T], FileInfo) ->
+    do_apply_file_info_opts(T, FileInfo#file_info{atime=Value});
+do_apply_file_info_opts([{mtime,Value}|T], FileInfo) ->
+    do_apply_file_info_opts(T, FileInfo#file_info{mtime=Value});
+do_apply_file_info_opts([{ctime,Value}|T], FileInfo) ->
+    do_apply_file_info_opts(T, FileInfo#file_info{ctime=Value});
+do_apply_file_info_opts([{uid,Value}|T], FileInfo) ->
+    do_apply_file_info_opts(T, FileInfo#file_info{uid=Value});
+do_apply_file_info_opts([{gid,Value}|T], FileInfo) ->
+    do_apply_file_info_opts(T, FileInfo#file_info{gid=Value});
+do_apply_file_info_opts([_|T], FileInfo) ->
+    do_apply_file_info_opts(T, FileInfo);
+do_apply_file_info_opts([], FileInfo) ->
+    FileInfo.
+
+apply_file_info_opts_fun(Options, InfoFunction) ->
+   fun(F) ->
+       apply_file_info_opts(Options, file:InfoFunction(F, [{time, posix}]))
+   end.
+
 add1(#reader{}=Reader, Name, NameInArchive, #add_opts{read_info=ReadInfo}=Opts)
   when is_list(Name) ->
     Res = case ReadInfo(Name) of
@@ -515,9 +550,11 @@ add1(Reader, Bin, NameInArchive, Opts) when is_binary(Bin) ->
                 name = NameInArchive,
                 size = byte_size(Bin),
                 typeflag = ?TYPE_REGULAR,
-                atime = Now,
-                mtime = Now,
-                ctime = Now,
+                atime = add_opts_time(Opts#add_opts.atime, Now),
+                mtime = add_opts_time(Opts#add_opts.mtime, Now),
+                ctime = add_opts_time(Opts#add_opts.ctime, Now),
+                uid = Opts#add_opts.uid,
+                gid = Opts#add_opts.gid,
                 mode = 8#100644},
     {ok, Reader2} = add_header(Reader, Header, Opts),
     Padding = skip_padding(byte_size(Bin)),
@@ -527,6 +564,9 @@ add1(Reader, Bin, NameInArchive, Opts) when is_binary(Bin) ->
         {error, Reason} -> {error, {NameInArchive, Reason}}
     end.
 
+add_opts_time(undefined, Now) -> Now;
+add_opts_time(Time, _Now) -> Time.
+
 add_directory(Reader, DirName, NameInArchive, Info, Opts) ->
     case file:list_dir(DirName) of
         {ok, []} ->
-- 
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