Merge branch 'peppe/jcl_mode_improvements'

* peppe/jcl_mode_improvements:
  Fix problem with unitialized edlin text buffer
  Fix shell crash when in switch command mode

OTP-12673

2 files changed, 19 insertions, 1 deletions

diff --git a/lib/kernel/src/user_drv.erl b/lib/kernel/src/user_drv.erl
index e6ce85c379..380c685869 100644
--- a/lib/kernel/src/user_drv.erl
+++ b/lib/kernel/src/user_drv.erl
@@ -133,6 +133,7 @@ server1(Iport, Oport, Shell) ->
 		flatten(io_lib:format("~ts\n",
 				      [erlang:system_info(system_version)]))},
 	       Iport, Oport),
+
     %% Enter the server loop.
     server_loop(Iport, Oport, Curr, User, Gr, queue:new()).
 
@@ -315,6 +316,9 @@ handle_escape(Iport, Oport, User, Gr, IOQueue) ->
 
 	_ ->					% {ok,jcl} | undefined
 	    io_request({put_chars,unicode,"\nUser switch command\n"}, Iport, Oport),
+	    %% init edlin used by switch command and have it copy the
+	    %% text buffer from current group process
+	    edlin:init(gr_cur_pid(Gr)),
 	    server_loop(Iport, Oport, User, switch_loop(Iport, Oport, Gr), IOQueue)
     end.
 
diff --git a/lib/stdlib/src/edlin.erl b/lib/stdlib/src/edlin.erl
index b3bc5f6d92..362669545e 100644
--- a/lib/stdlib/src/edlin.erl
+++ b/lib/stdlib/src/edlin.erl
@@ -21,7 +21,7 @@
 %% A simple Emacs-like line editor.
 %% About Latin-1 characters: see the beginning of erl_scan.erl.
 
--export([init/0,start/1,start/2,edit_line/2,prefix_arg/1]).
+-export([init/0,init/1,start/1,start/2,edit_line/2,prefix_arg/1]).
 -export([erase_line/1,erase_inp/1,redraw_line/1]).
 -export([length_before/1,length_after/1,prompt/1]).
 -export([current_line/1, current_chars/1]).
@@ -44,6 +44,20 @@
 init() ->
     put(kill_buffer, []).
 
+init(Pid) ->
+    %% copy the kill_buffer from the process Pid
+    CopiedKillBuf =
+	case erlang:process_info(Pid, dictionary) of
+	    {dictionary,Dict} ->
+		case proplists:get_value(kill_buffer, Dict) of
+		    undefined -> [];
+		    Buf       -> Buf
+		end;
+	    undefined ->
+		[]
+	end,
+    put(kill_buffer, CopiedKillBuf).
+
 %% start(Prompt)
 %% edit(Characters, Continuation)
 %%  Return