From 67b055009db0f56f33e4cd0b7334bb7484dc35be Mon Sep 17 00:00:00 2001
From: Cloud Wu <cloudwu@gmail.com>
Date: Mon, 20 Mar 2017 16:25:15 +0800
Subject: [PATCH] bugfix isse #592

---
 service/debug_agent.lua   | 14 +++++++++++---
 service/debug_console.lua | 22 +++++++++++++++++++---
 2 files changed, 30 insertions(+), 6 deletions(-)

diff --git a/service/debug_agent.lua b/service/debug_agent.lua
index b4c4667d..451e2215 100644
--- a/service/debug_agent.lua
+++ b/service/debug_agent.lua
@@ -10,9 +10,13 @@ function CMD.start(address, fd)
 	skynet.error(string.format("Attach to :%08x", address))
 	local handle
 	channel, handle = debugchannel.create()
-	skynet.call(address, "debug", "REMOTEDEBUG", fd, handle)
-	-- todo hook
-	skynet.ret(skynet.pack(nil))
+	local ok, err = pcall(skynet.call, address, "debug", "REMOTEDEBUG", fd, handle)
+	if not ok then
+		skynet.ret(skynet.pack(false, "Debugger attach failed"))
+	else
+		-- todo hook
+		skynet.ret(skynet.pack(true))
+	end
 	skynet.exit()
 end
 
@@ -20,6 +24,10 @@ function CMD.cmd(cmdline)
 	channel:write(cmdline)
 end
 
+function CMD.ping()
+	skynet.ret()
+end
+
 skynet.start(function()
 	skynet.dispatch("lua", function(_,_,cmd,...)
 		local f = CMD[cmd]
diff --git a/service/debug_console.lua b/service/debug_console.lua
index d76a1e58..2db38e46 100644
--- a/service/debug_console.lua
+++ b/service/debug_console.lua
@@ -91,7 +91,7 @@ end
 local function console_main_loop(stdin, print)
 	print("Welcome to skynet console")
 	skynet.error(stdin, "connected")
-	pcall(function()
+	local ok, err = pcall(function()
 		while true do
 			local cmdline = socket.readline(stdin, "\n")
 			if not cmdline then
@@ -109,6 +109,9 @@ local function console_main_loop(stdin, print)
 			end
 		end
 	end)
+	if not ok then
+		skynet.error(stdin, err)
+	end
 	skynet.error(stdin, "disconnected")
 	socket.close(stdin)
 end
@@ -262,8 +265,11 @@ function COMMANDX.debug(cmd)
 	local address = adjust_address(cmd[2])
 	local agent = skynet.newservice "debug_agent"
 	local stop
-	skynet.fork(function()
+	local term_co = coroutine.running()
+	local function forward_cmd()
 		repeat
+			-- notice :  It's a bad practice to call socket.readline from two threads (this one and console_main_loop), be careful.
+			skynet.call(agent, "lua", "cmd", "ping")	-- detect agent alive, if agent exit, raise error
 			local cmdline = socket.readline(cmd.fd, "\n")
 			cmdline = cmdline and cmdline:gsub("(.*)\r$", "%1")
 			if not cmdline then
@@ -272,9 +278,19 @@ function COMMANDX.debug(cmd)
 			end
 			skynet.send(agent, "lua", "cmd", cmdline)
 		until stop or cmdline == "cont"
+	end
+	skynet.fork(function()
+		pcall(forward_cmd)
+		skynet.wakeup(term_co)
 	end)
-	skynet.call(agent, "lua", "start", address, cmd.fd)
+	local ok, err = skynet.call(agent, "lua", "start", address, cmd.fd)
 	stop = true
+	-- wait for fork coroutine exit.
+	skynet.wait(term_co)
+
+	if not ok then
+		error(err)
+	end
 end
 
 function COMMAND.logon(address)