File 2033-peer-Allow-peers-to-stay-attached-and-use-... of Package erlang

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File 2033-peer-Allow-peers-to-stay-attached-and-use-tty.patch of Package erlang (Revision db1acd30fa2136b2cf32ed954074cb8e)

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From 7f7eac7f92b15f2fb570fe62ce891b6fe75f81cc Mon Sep 17 00:00:00 2001
From: Lukas Larsson <lukas@erlang.org>
Date: Sun, 15 May 2022 22:51:29 +0200
Subject: [PATCH 3/4] peer: Allow peers to stay attached and use tty

---
 erts/etc/common/erlexec.c      | 13 ++++----
 lib/kernel/src/user_sup.erl    |  7 ++--
 lib/stdlib/doc/src/peer.xml    |  7 ++++
 lib/stdlib/src/peer.erl        | 58 ++++++++++++++++++++++++++--------
 lib/stdlib/test/peer_SUITE.erl | 36 +++++++++++++++++++--
 5 files changed, 94 insertions(+), 27 deletions(-)

diff --git a/erts/etc/common/erlexec.c b/erts/etc/common/erlexec.c
index 9c3dc690ba..b1e2118b7a 100644
--- a/erts/etc/common/erlexec.c
+++ b/erts/etc/common/erlexec.c
@@ -650,13 +650,12 @@ int main(int argc, char **argv)
 		    break;
 
 		  case 'd':
-		    if (strcmp(argv[i], "-detached") != 0) {
-			add_arg(argv[i]);
-		    } else {
-			start_detached = 1;
-			add_args("-noshell", "-noinput", NULL);
-		    }
-		    break;
+                    add_arg(argv[i]);
+                    if (strcmp(argv[i], "-detached") == 0) {
+                        start_detached = 1;
+                        add_args("-noshell", "-noinput", NULL);
+                    }
+                    break;
 
 		  case 'e':
 		    if (strcmp(argv[i], "-extra") == 0) {
diff --git a/lib/kernel/src/user_sup.erl b/lib/kernel/src/user_sup.erl
index c1fb1b1a48..6206a8d0ab 100644
--- a/lib/kernel/src/user_sup.erl
+++ b/lib/kernel/src/user_sup.erl
@@ -39,7 +39,9 @@ start() ->
 -spec init([]) -> 'ignore' | {'error', 'nouser'} | {'ok', pid(), pid()}.
 
 init([]) ->
-    case get_user() of
+    init(init:get_arguments());
+init(Flags) ->
+    case get_user(Flags) of
 	nouser ->
 	    ignore;
 	{master, Master} ->
@@ -112,8 +114,7 @@ wait_for_user_p(N) ->
 	    wait_for_user_p(N-1)
     end.
 
-get_user() ->
-    Flags = init:get_arguments(),
+get_user(Flags) ->
     check_flags(Flags, {user_drv, start, []}).
 
 %% These flags depend upon what arguments the erl script passes on
diff --git a/lib/stdlib/doc/src/peer.xml b/lib/stdlib/doc/src/peer.xml
index 299a2b1df2..71bf71e75e 100644
--- a/lib/stdlib/doc/src/peer.xml
+++ b/lib/stdlib/doc/src/peer.xml
@@ -308,6 +308,13 @@ build_image(Dir) ->
               default bash.
             </p>
           </item>
+          <tag><c>detached</c></tag>
+          <item>
+            <p>Defines whether to pass the <c>-detached</c> flag to the started peer.
+              This option cannot be set to <c>false</c> using the standard_io alternative
+              connection type. Default is <c>true</c>.
+            </p>
+          </item>
           <tag><c>args</c></tag>
           <item>
             <p>Extra command line arguments to append to the "erl" command. Arguments are
diff --git a/lib/stdlib/src/peer.erl b/lib/stdlib/src/peer.erl
index f9eefe3d0f..fa2cf53f23 100644
--- a/lib/stdlib/src/peer.erl
+++ b/lib/stdlib/src/peer.erl
@@ -115,6 +115,7 @@
           %%  terminates with underlying reason
           connection => connection(),         %% alternative connection specification
           exec => exec(),                     %% path to executable, or SSH/Docker support
+          detached => boolean(),              %% if the node should be start in detached mode
           args => [string()],                 %% additional command line parameters to append
           post_process_args =>
               fun(([string()]) -> [string()]),%% fix the arguments
@@ -571,8 +572,13 @@ verify_args(Options) ->
             ok;
         {ok, Err2} ->
             error({shutdown, Err2})
+    end,
+    case maps:find(detached, Options) of
+        {ok, false} when map_get(connection, Options) =:= standard_io ->
+            error({detached, cannot_detach_with_standard_io});
+        _ ->
+            ok
     end.
-            
 
 make_notify_ref(infinity) ->
     {self(), make_ref()};
@@ -788,6 +794,14 @@ command_line(Listen, Options) ->
     NameArg = name_arg(maps:find(name, Options), maps:find(host, Options), maps:find(longnames, Options)),
     %% additional command line args
     CmdOpts = maps:get(args, Options, []),
+
+    %% If we should detach from the node. We use -detached to tell erl to detach
+    %% and -peer_detached to tell peer:start that we are detached.
+    DetachArgs = case maps:get(detached, Options, true) of
+                     true -> ["-detached","-peer_detached"];
+                     false -> []
+                 end,
+
     %% start command
     StartCmd =
         case Listen of
@@ -795,14 +809,14 @@ command_line(Listen, Options) ->
                 ["-user", atom_to_list(?MODULE)];
             undefined ->
                 Self = base64:encode_to_string(term_to_binary(self())),
-                ["-detached", "-noinput", "-user", atom_to_list(?MODULE), "-origin", Self];
+                DetachArgs ++ ["-user", atom_to_list(?MODULE), "-origin", Self];
             {Ips, Port} ->
                 IpStr = lists:concat(lists:join(",", [inet:ntoa(Ip) || Ip <- Ips])),
-                ["-detached", "-noinput", "-user", atom_to_list(?MODULE), "-origin", IpStr, integer_to_list(Port)]
+                DetachArgs ++ ["-user", atom_to_list(?MODULE), "-origin", IpStr, integer_to_list(Port)]
         end,
     %% build command line
     {Exec, PreArgs} = exec(Options),
-    {Exec, PreArgs ++ NameArg ++ StartCmd ++ CmdOpts}.
+    {Exec, PreArgs ++ NameArg ++ CmdOpts ++ StartCmd}.
 
 exec(#{exec := Prog}) when is_list(Prog) ->
     {Prog, []};
@@ -1022,23 +1022,41 @@ start_peer_channel_handler() ->
         {ok, [[IpStr, PortString]]} ->
             %% enter this clause when -origin IpList Port is specified in the command line.
             Port = list_to_integer(PortString),
-            Ips = [begin {ok, Addr} = inet:parse_address(Ip), Addr end || Ip <- string:lexemes(IpStr, ",")],
-            spawn(fun () -> tcp_init(Ips, Port) end);
+            Ips = [begin {ok, Addr} = inet:parse_address(Ip), Addr end ||
+                      Ip <- string:lexemes(IpStr, ",")],
+            TCPConnection = spawn(fun () -> tcp_init(Ips, Port) end),
+            case init:get_argument(peer_detached) of
+                {ok, _} ->
+                    register(user, TCPConnection),
+                    TCPConnection;
+                error ->
+                    user_sup:init(
+                      [Flag || Flag <- init:get_arguments(), Flag =/= {user,["peer"]}])
+            end;
         {ok, [[Base64EncProc]]} ->
             %% No alternative connection, but have "-origin Base64EncProc"
             OriginProcess = binary_to_term(base64:decode(Base64EncProc)),
-            %% setup 'user' process, I/O redirection: ask controlling process
-            %%  who is the group leader.
-            GroupLeader = gen_server:call(OriginProcess, group_leader),
-            RelayPid = spawn(fun () -> relay(GroupLeader) end),
-            register(user, RelayPid),
             spawn(
               fun () ->
-                      link(RelayPid),
                       MRef = monitor(process, OriginProcess),
                       notify_when_started(dist, OriginProcess),
                       origin_link(MRef, OriginProcess)
-              end);
+              end),
+            case init:get_argument(peer_detached) of
+                {ok, _} ->
+                    %% We are detached, so setup 'user' process, I/O redirection:
+                    %%   ask controlling process who is the group leader.
+                    GroupLeader = gen_server:call(OriginProcess, group_leader),
+                    RelayPid = spawn(fun () -> relay(GroupLeader) end),
+                    register(user, RelayPid),
+                    %% return RelayPid for user_sup to link to
+                    RelayPid;
+                error ->
+                    %% We are not detached, so after we spawn the link process we
+                    %% start the terminal as normal but without the -user peer flag.
+                    user_sup:init(
+                      [Flag || Flag <- init:get_arguments(), Flag =/= {user,["peer"]}])
+            end;
         error ->
             %% no -origin specified, meaning that standard I/O is used for alternative
             spawn(fun io_server/0)
@@ -949,7 +980,6 @@ io_server() ->
 tcp_init(IpList, Port) ->
     try
         Sock = loop_connect(IpList, Port),
-        register(user, self()),
         erlang:group_leader(self(), self()),
         notify_when_started(tcp, Sock),
         io_server_loop(tcp, Sock, #{}, #{}, undefined)
diff --git a/lib/stdlib/test/peer_SUITE.erl b/lib/stdlib/test/peer_SUITE.erl
index 2612cac48d..5de72cea4f 100644
--- a/lib/stdlib/test/peer_SUITE.erl
+++ b/lib/stdlib/test/peer_SUITE.erl
@@ -47,6 +47,7 @@
     ssh/0, ssh/1,
     docker/0, docker/1,
     post_process_args/0, post_process_args/1,
+    attached/0, attached/1,
     cntrl_channel_handler_crash/0, cntrl_channel_handler_crash/1,
     cntrl_channel_handler_crash_old_release/0, cntrl_channel_handler_crash_old_release/1
 ]).
@@ -59,13 +60,13 @@ shutdown_alternatives() ->
 
 alternative() ->
     [basic, peer_states, cast, detached, dyn_peer, stop_peer,
-     io_redirect, multi_node, duplicate_name, cntrl_channel_handler_crash,
-     cntrl_channel_handler_crash_old_release | shutdown_alternatives()].
+     io_redirect, multi_node, duplicate_name, attached,
+     cntrl_channel_handler_crash, cntrl_channel_handler_crash_old_release | shutdown_alternatives()].
 
 groups() ->
     [
         {dist, [parallel], [errors, dist, peer_down_crash, peer_down_continue, peer_down_boot,
-                            dist_up_down, dist_localhost, post_process_args,
+                            dist_up_down, dist_localhost, post_process_args, attached,
                             cntrl_channel_handler_crash,
                             cntrl_channel_handler_crash_old_release | shutdown_alternatives()]},
         {dist_seq, [], [dist_io_redirect,      %% Cannot be run in parallel in dist group
@@ -593,6 +594,35 @@ docker(Config) when is_list(Config) ->
             peer:stop(Peer)
     end.
 
+attached() ->
+    [{doc, "Test that it is possible to start a peer node using run_erl aka attached"}].
+
+attached(Config) ->
+    RunErl = os:find_executable("run_erl"),
+    [throw({skip, "Could not find run_erl"}) || RunErl =:= false],
+    Erl = string:split(ct:get_progname()," ",all),
+    RunErlDir = filename:join(proplists:get_value(priv_dir, Config),?FUNCTION_NAME),
+    filelib:ensure_path(RunErlDir),
+    Connection = proplists:get_value(connection, Config),
+    Conn = if Connection =:= undefined -> #{ name => ?CT_PEER_NAME() };
+              true -> #{ connection => Connection }
+           end,
+    try peer:start(
+           Conn#{
+                 exec => {RunErl, Erl},
+                 detached => false,
+                 post_process_args =>
+                     fun(Args) ->
+                             [RunErlDir ++ "/", RunErlDir,
+                              lists:flatten(lists:join(" ",[[$',A,$'] || A <- Args]))]
+                     end
+                }) of
+        {ok, Peer, _Node} when Connection =:= undefined; Connection =:= 0 ->
+            peer:stop(Peer)
+    catch error:{detached,_} when Connection =:= standard_io ->
+            ok
+    end.
+
 cntrl_channel_handler_crash() ->
     [{doc, "Test that peer node is halted if peer control channel handler process crashes"}].
 
-- 
2.35.3

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File 2033-peer-Allow-peers-to-stay-attached-and-use-tty.patch of Package erlang (Revision db1acd30fa2136b2cf32ed954074cb8e)

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