Add some documents for management GUI and protocol.

readme.md

@@ -304,15 +304,118 @@ The EPC has some debug functions for analyzing low level communication.
 
 ## Management Interface
 
-TODO...
+The EPC has a management interface for the EPC connections. Users can check the current connection status, inspect method specs and terminate the connection.
+
+### Current Connections
+
+Executing `M-x epc:controller`, one can display the list of current established connections.
+
+![Current Connections](img/mm-conns.png)
+
+This table shows following information:
+
+| Column | Note |
+|--------|------|
+| <Process> | Process name |
+| <Proc> | Process status (`process-status` for the process) |
+| <Conn> | Connection status (`process-status` for the TCP connection) |
+| Title | Connection title which is defined by the EPC user program. |
+| Command | Process command and arguments. |
+| Port | TCP port which is opened by the remote process. |
+| Methods | Number of methods which are defined at the Emacs side. |
+| Live sessions | Number of sessions which are waiting for a return value.|
+
+One can use following key-bind:
+
+| Key | Command | Note |
+|-----|---------|------|
+| g | `epc:controller-update-command` | Refresh the table. |
+| R | `epc:controller-connection-restart-command` | Restart the selected connection. |
+| D,K | `epc:controller-connection-kill-command` | Kill the selected process and connection. |
+| m,RET | `epc:controller-methods-show-command` | Display a method list of the remote process. (See the next sub-section for details.) |
+| B | `epc:controller-connection-buffer-command` | Display the connection buffer. |
+
+### Remote Method List
+
+Displaying a method list, one can inspect the methods which are defined by the remote process.
+
+![Remote Method List](img/mm-methods.png)
+
+This table shows following information:
+
+| Column | Note |
+|--------|------|
+| Method Name | Method name to call.|
+| Arguments | [optional] Argument names.|
+| Document | [optional] Method spec document.|
+
+Here, 'Arguments' and 'Document' may be blank, because those are not essential slots.
+
+| Key | Command | Note |
+|-----|---------|------|
+| e | `epc:controller-methods-eval-command` | Evaluate the selected remote method with some arguments. |
+| q | `bury-buffer`| Bury this buffer. |
 
 # Implementation
 
 This section describes the EPC architecture and the wire-protocol so as to implement the peer stacks.
 
 ## Protocol Details
 
-TODO...
+The EPC protocol is based on the SWANK protocol.
+
+- [Understanding SLIME (Using Emacs and Lisp Cooperatively)](http://bc.tech.coop/blog/081209.html)
+
+### Message Envelope
+
+- PAYLOAD-LENGTH  : 24-bit hex-encoded integer
+- PAYLOAD-CONTENT : S-expression, text, utf-8
+  - (MESSAGE-TYPE . MESSAGE-BODY-LIST)
+
+- MESSAGE-TYPE : `call` | `return` | `return-error` | `epc-error` | `methods`
+- MESSAGE-BODY-LIST : (Dependent on message types.)
+
+### Message [call]
+
+This message represents initiating method calling.
+
+- MESSAGE-BODY-LIST : `(call UID METHOD-NAME ARGS)`
+  - UID : The session ID, which is an unique ID generated by the caller side.
+  - METHOD-NAME : A symbol for method name.
+  - ARGS : A list of method arguments.
+
+### Message [return]
+
+This message represents the normal finish of the method calling.
+
+- MESSAGE-BODY-LIST : `(return UID RETURN-VALUE)`
+  - UID : The session ID to return.
+  - RETURN-VALUE : A return object.
+
+### Message [return-error]
+
+This message represents the application error, which is due to the application.
+
+- MESSAGE-BODY-LIST : `(return-error UID ERROR-MESSAGE)`
+  - UID : The session ID to return.
+  - ERROR-MESSAGE : An error message.
+
+### Message [epc-error]
+
+This message represents the EPC error, which is due to the EPC stack.
+
+- MESSAGE-BODY-LIST : `(epc-error UID ERROR-MESSAGE)`
+  - UID : The session ID to return.
+  - ERROR-MESSAGE : An error message.
+
+### Message [methods]
+
+This message represents the method query.
+
+- MESSAGE-BODY-LIST : `(methods UID)`
+  - UID : The session ID, which is an unique ID generated by the caller side.
+
+The response message is returned by the `return` message.
 
 ## Other Stacks