Switch to rebar3 and an escript.

This also contains various commits I found in other places which seemed
useful.  I updated the README to reflect where the escript is built.
The shell script is no longer necessary so was removed.

Author: djnym

.gitignore

@@ -1,2 +1,5 @@
 *.beam
 deps
+_build
+.rebar3
+rebar.lock

README.md

@@ -3,45 +3,46 @@ A top-like Erlang node monitoring tool
 
 
 ## Introduction
-Entop is a tool which shows information about a remote Erlang node in a way which is similar to unix 'top'. 
+Entop is a tool which shows information about a remote Erlang node in a way which is similar to unix 'top'.
 
-For entop to run it needs `cecho 0.3.0` or higher for pre-R15 or `cecho 0.4.0` or higher for R15 and above
+For entop to run it needs `cecho 0.5.1` or higher
 (http://www.github.com/mazenharake/cecho).
 
 ## Compile
 To clean/compile run
 
-    ./rebar clean
-    ./rebar compile
+    ./rebar3 clean
+    ./rebar3 escriptize
 
-NOTE: If you have problems with dependencies to `cecho` then create a symlink to cecho in `deps/` (if you already have cecho somewhere) or run `./rebar get-deps` to download the latest version. Don't forget to recompile if you get the dependencies through rebar.
+A relocatable escript named 'entop' is now in '_build/default/bin/entop', you can copy that to your path somewhere.
 
 ## Usage
-To run entop make sure you have Erlang installed and that the cecho library (http://www.github.com/mazenharake/cecho) is available in your Erlang code path. The start script assumes that you run it inside the entop application root directory, if you don't want that then change the paths in the scripts accordingly or just make sure you have the ebin/ directory for entop in your Erlang code path. Look at the start script for more details.
+To run entop make sure you have Erlang installed and that the escript is in your path.
 
-    Usage: ./entop <TARGETNODE> [-name <NAME>|-sname <SNAME>] [-setcookie <COOKIE>]
+    Usage: ./entop <TARGETNODE> [<COOKIE>]
 
 ### An example of how you run entop:
 
-    > ./entop [email protected] -name [email protected] -setcookie secret
+    > ./entop [email protected] secret
 
 ### User Interface:
 entop's interface can be customized so this section only applies for the "built-in" interface.
 
 #### Headers
-**First row** shows information about the node which is more or less static such as the node name the operating system, erl flags and erlang version it is running.    
-**The second** row shows information on what the local time is (according to the node), how long it has been up for (Days:Hours:Minutes:Seconds) and how much latency there is to the node I.e. how long a net_adm:ping() takes.    
-**Third row** shows information about the processes of the system; the total number of processes, the run queue (number of processes scheduled to run by the scheduler(s)), the reductions per interval (RpI) which shows how many reductions the system has made since it last called the node and how much memory the processes are using.   
-**Fourth row** shows how much system memory, atom memory (currently used/total allocated), binary memory, code memory and ets memory.    
-**Fifth row** is left blank and is reserved for now.    
-**Sixth row** shows information about the rows in the list such as the interval in which the information is fetched, what the list is sorted on and how long it took to retrieve the information.
+**First row** shows information about the node which is more or less static such as the node name the operating system, erl flags and erlang version it is running.
+**Second row** shows information on what the local time is (according to the node), how long it has been up for (Days:Hours:Minutes:Seconds) and how much latency there is to the node I.e. how long a net_adm:ping() takes.
+**Third row** shows information about the processes of the system; the total number of processes, the run queue (number of processes scheduled to run by the scheduler(s)), the reductions per interval (RpI) which shows how many reductions the system has made since it last called the node.
+**Fourth row** shows how much process memory is being used and the total amount.
+**Fifth row** shows how much system memory, atom memory (currently used/total allocated), binary memory, code memory and ets memory.
+**Sixth row** is left blank and is reserved for now.
+**Seventh row** shows information about the rows in the list such as the interval in which the information is fetched, what the list is sorted on and how long it took to retrieve the information.
 
 ### Commands when running entop:
 
-[1-N]: 
+[1-N]:
   Sort on column number 1 through N. Starts with first column (1) and up to N
   where N is the last column.
-    
+
 r:
   Toggles the sorting order from ascending to descending and vice versa.
 

entop

@@ -1,5 +1,13 @@
-{erl_opts, [fail_on_warning, debug_info]}.
-{deps_dir, "deps"}.
-{clean_files, ["ebin/*.beam"]}.
-{deps, [{cecho, ".*", {git, "https://github.com/mazenharake/cecho.git", "HEAD"}}]}.
-{escript_name, "rebar_tmp"}.
+{erl_opts, [fail_on_warning,
+            debug_info,
+            {platform_define, "^(R14|R15|R16B|17)", 'random_module_available'}
+           ]}.
+
+{escript_emu_args, "%%! -hidden -noinput +A 20 +Bc"}.
+
+{ deps, [
+    {cecho, ".*",
+      {git, "https://github.com/mazenharake/cecho.git", {tag, "0.5.1"}}
+    }
+  ]
+}.

rebar

@@ -1,7 +1,15 @@
 {application, entop,
  [{description, "A top-like tool for monitoring an erlang node"},
-  {vsn, "0.0.1"},
-  {modules, [entop,  entop_collector, entop_format, entop_view, entop_net]},
-  {applications, []},
+  {vsn, "0.3.0"},
   {registered, []},
-  {env, []}]}.
+  {applications,
+   [kernel,
+    stdlib,
+    cecho
+   ]},
+  {env,[]},
+  {modules, [entop,  entop_collector, entop_format, entop_view, entop_net]},
+  {maintainers, []},
+  {licenses, ["Apache 2.0"]},
+  {links, []}
+ ]}.

rebar.config

@@ -20,9 +20,91 @@
 -include("entop.hrl").
 -include_lib("cecho/include/cecho.hrl").
 
+%% escript bits
+-export([main/1]).
+
 %% Application API
 -export([start/1]).
 
+-ifdef(random_module_available).
+rand_seed() ->
+  random:seed(os:timestamp()).
+rand_uniform(N) ->
+  random:uniform(N).
+-else.
+rand_seed() ->
+  ok.
+rand_uniform(N) ->
+  rand:uniform(N).
+-endif.
+
+main([]) ->
+  io:format("Usage: ./entop <TARGETNODE> [<COOKIE>]~n", []),
+  halt(1);
+main([Node]) ->
+  main([Node,undefined]);
+main([NodeIn,CookieIn]) ->
+  % node and cookie should both be atoms
+  Node = normalize_to_atom(NodeIn),
+  Cookie = normalize_to_atom(CookieIn),
+  case name_type(Node) of
+    { error, improper_node_name } ->
+      io:format("Nodename ~p is malformed, use form 'node@host'~n", [Node]),
+      halt(101);
+    {ok, NameType} ->
+      case net_kernel:start(NameType) of
+        {ok, _} ->
+          case maybe_set_cookie(Node,Cookie) of
+            ok ->
+              case net_kernel:connect(Node) of
+                true ->
+                  ViewPid = entop_view:start(#state{ node = Node,
+                                                     connected = true }),
+                  control(ViewPid);
+                false ->
+                  io:format("Unable to connect to '~p', check nodename, cookie and network~n",[Node]),
+                  halt(101)
+              end;
+            CE ->
+              io:format("Cookie ~p is malformed, got error ~p~n", [Cookie,CE]),
+              halt(101)
+          end;
+        NetError ->
+          io:format("Couldn't start network with ~p, got error ~p~n",
+                    [NameType, NetError]),
+          halt(101)
+      end
+  end.
+
+normalize_to_atom(L) when is_list(L) ->
+  list_to_atom(L);
+normalize_to_atom(A) when is_atom(A) ->
+  A.
+
+maybe_set_cookie(_, undefined) -> ok;
+maybe_set_cookie(Node, Cookie) ->
+  case erlang:set_cookie(Node,Cookie) of
+    true -> ok;
+    E -> E
+  end.
+
+name_type (Node) when is_atom(Node) ->
+  name_type(atom_to_list(Node));
+name_type (Node) when is_list(Node) ->
+  case string:tokens(Node,"@") of
+    [_] -> {error, improper_node_name};
+    [N,H] ->
+      T =
+        case lists:member($.,H) of
+          true -> longnames;
+          false -> shortnames
+        end,
+      rand_seed(),
+      R = rand_uniform(1000000),
+      EntopName = list_to_atom("entop-" ++ integer_to_list(R) ++ "-" ++ N),
+      {ok,[EntopName,T]}
+  end.
+
 %% =============================================================================
 %% Application API
 %% =============================================================================