chore: fix crash in loop_gc

src/handle.c

@@ -88,13 +88,19 @@ static int luv_is_closing(lua_State* L) {
   return 1;
 }
 
+static void luv_handle_free(uv_handle_t* handle);
+
 static void luv_close_cb(uv_handle_t* handle) {
   lua_State* L;
   luv_handle_t* data = (luv_handle_t*)handle->data;
   if (!data) return;
   L = data->ctx->L;
-  luv_call_callback(L, data, LUV_CLOSED, 0);
-  luv_unref_handle(L, data);
+  if(data->ref > 0) {
+    luv_call_callback(L, data, LUV_CLOSED, 0);
+    luv_unref_handle(L, data);
+  } else {
+    luv_handle_free(handle);
+  }
 }
 
 static int luv_close(lua_State* L) {
@@ -127,19 +133,24 @@ static void luv_gc_cb(uv_handle_t* handle) {
 static int luv_handle_gc(lua_State* L) {
   uv_handle_t** udata = (uv_handle_t**)lua_touserdata(L, 1);
   uv_handle_t* handle = *udata;
+  luv_handle_t* data = (luv_handle_t*)handle->data;
 
   // Only cleanup if the handle hasn't been cleaned up yet.
-  if (handle) {
+  if (data->ref == LUA_NOREF) {
     if (!uv_is_closing(handle)) {
       // If the handle is not closed yet, close it first before freeing memory.
-      uv_close(handle, luv_gc_cb);
+      uv_close(handle, luv_handle_free);
     }
     else {
       // Otherwise, free the memory right away.
       luv_handle_free(handle);
     }
     // Mark as cleaned up by wiping the dangling pointer.
     *udata = NULL;
+  } else {
+    // os.exit maybe cause gc before close_cb
+    // use LUA_REFNIL to tell close_cb to free memory.
+    data->ref = LUA_REFNIL;
   }
 
   return 0;

src/lhandle.c

@@ -104,6 +104,7 @@ static void luv_call_callback(lua_State* L, luv_handle_t* data, luv_callback_id
 
 static void luv_unref_handle(lua_State* L, luv_handle_t* data) {
   luaL_unref(L, LUA_REGISTRYINDEX, data->ref);
+  data->ref = LUA_NOREF;
   luaL_unref(L, LUA_REGISTRYINDEX, data->callbacks[0]);
   luaL_unref(L, LUA_REGISTRYINDEX, data->callbacks[1]);
 }

tests/manual-test-exit.lua

@@ -0,0 +1,22 @@
+--come from https://github.com/luvit/luv/issues/599
+
+-- run `lua manual-test-exit.lua || echo $?`
+-- it shoud print `5`
+
+local uv = require('luv')
+
+local function setTimeout(callback, ms)
+  local timer = uv.new_timer()
+  timer:start(ms, 0, function()
+    timer:stop()
+    timer:close()
+    callback()
+  end)
+  return timer
+end
+
+setTimeout(function()
+  os.exit(5, true)
+end, 1000)
+
+uv.run()

tests/manual-test-without-uv.run.lua

@@ -0,0 +1,4 @@
+local uv = require('luv')
+
+local test = uv.new_pipe(false)
+uv.close(test)

tests/test-loop.lua

@@ -1,5 +1,18 @@
 return require('lib/tap')(function (test)
 
+  local function get_cmd()
+    local i=1
+    repeat
+      i=i-1
+    until not arg[i]
+    return arg[i+1]
+  end
+
+  local cmd = get_cmd()
+  local cwd = require('luv').cwd()
+  print("cmd: ", cmd)
+  print("cwd: ", cwd)
+
 	test("uv.loop_mode", function (print, p, expect, uv)
 		assert(uv.loop_mode() == nil)
     local timer = uv.new_timer()
@@ -10,4 +23,48 @@ return require('lib/tap')(function (test)
     end))
   end)
 
+  test("issue #437, crash without uv.run", function (print, p, expect, uv)
+    local handle
+    local stdout = uv.new_pipe(false)
+
+    handle = uv.spawn(cmd, {
+      args = { "tests/manual-test-without-uv.run.lua" },
+      cwd = cwd,
+      stdio = {nil, stdout},
+    },
+    expect(function(status, signal)
+      print('#437', status, signal)
+      assert(status==0)
+      assert(signal==0)
+      handle:close()
+    end))
+
+    uv.read_start(stdout, expect(function (err, chunk)
+      p("stdout", {err=err,chunk=chunk})
+      uv.close(stdout)
+    end))
+  end)
+
+  test("issue #599, crash during calling os.exit", function (print, p, expect, uv)
+    local handle
+    local stdout = uv.new_pipe(false)
+
+    handle = uv.spawn(cmd, {
+      args = { "tests/manual-test-exit.lua" },
+      cwd = cwd,
+      stdio = {nil, stdout},
+    },
+    expect(function(status, signal)
+      print('#599', status, signal)
+      assert(status==5)
+      assert(signal==0)
+      handle:close()
+    end))
+
+    uv.read_start(stdout, expect(function (err, chunk)
+      p("stdout", {err=err,chunk=chunk})
+      uv.close(stdout)
+    end))
+  end)
+
 end)