[PATCH v2] tarantoolctl: return an error on enter to a dead socket.

[Serge Petrenko <sergepetrenko@tarantool.org>]

Tarantoolctl enter didn't check whether connection to a socket was established
if a socket file existed. It just executed a local console.
Fix this by adding a check and an error, also add a test case.

Closes #3364
---
https://github.com/tarantool/tarantool/issues/3364
https://github.com/tarantool/tarantool/tree/sergepetrenko/gh-3364-tarantoolctl-enter-fix

Changes in v2:
  - alter testcase.
  - remove explicit deletion of unix
    socket from patch due to poor
    implementation.

 extra/dist/tarantoolctl.in         | 19 +++++++++------
 test/app-tap/tarantoolctl.test.lua | 48 +++++++++++++++++++++++++++++++++++++-
 2 files changed, 59 insertions(+), 8 deletions(-)

diff --git a/extra/dist/tarantoolctl.in b/extra/dist/tarantoolctl.in
index 70747bd0c..6b6e78cd2 100755
--- a/extra/dist/tarantoolctl.in
+++ b/extra/dist/tarantoolctl.in
@@ -638,15 +638,20 @@ local function enter()
         end
         return 1
     end
-
-    local cmd = string.format(
-        "require('console').connect('%s', { connect_timeout = %s })",
-        console_sock, TIMEOUT_INFINITY
-    )
-
-    console.on_start(function(self) self:eval(cmd) end)
+    local status, ret
+    console.on_start(function(self)
+        status, ret = pcall(console.connect, console_sock,
+              {connect_timeout = TIMEOUT_INFINITY})
+        if not status then
+            log.error("Can't connect to %s (%s)", console_sock_path, ret)
+            self.running = false
+        end
+    end)
     console.on_client_disconnect(function(self) self.running = false end)
     console.start()
+    if not status then
+        return 1
+    end
     return 0
 end
 
diff --git a/test/app-tap/tarantoolctl.test.lua b/test/app-tap/tarantoolctl.test.lua
index ac9a208ca..c37c8f365 100755
--- a/test/app-tap/tarantoolctl.test.lua
+++ b/test/app-tap/tarantoolctl.test.lua
@@ -120,6 +120,14 @@ local function tctl_wait_stop(dir, name)
     end
 end
 
+local function wait_delete(path)
+    if path then
+        while fio.path.exists(path) do
+            fiber.sleep(0.001)
+        end
+    end
+end
+
 local function tctl_command(dir, cmd, args, name)
     local pid = nil
     if not fio.stat(fio.pathjoin(dir, '.tarantoolctl')) then
@@ -157,7 +165,7 @@ local function check_ok(test, dir, cmd, args, e_res, e_stdout, e_stderr)
 end
 
 local test = tap.test('tarantoolctl')
-test:plan(6)
+test:plan(7)
 
 -- basic start/stop test
 -- must be stopped afterwards
@@ -258,6 +266,44 @@ do
     end
 end
 
+-- check enter
+do
+    local dir = fio.tempdir()
+
+    local code = [[ box.cfg{} ]]
+    create_script(dir, 'script.lua', code)
+
+    local status, err = pcall(function()
+        test:test("check error codes in case of enter", function(test_i)
+            test_i:plan(10)
+            check_ok(test_i, dir, 'enter', 'script', 1, nil, "Can't connect to")
+            local console_sock = 'script.control'
+            console_sock = fio.pathjoin(dir, console_sock)
+            test_i:is(fio.path.exists(console_sock), false, "directory clean")
+            check_ok(test_i, dir, 'start', 'script', 0)
+            tctl_wait_start(dir, 'script')
+            test_i:is(fio.path.exists(console_sock), true,
+                      "unix socket created")
+            check_ok(test_i, dir, 'stop', 'script', 0)
+            wait_delete(console_sock)
+            test_i:is(fio.path.exists(console_sock), false,
+                      "remove unix socket upon exit")
+            fio.open(console_sock, 'O_CREAT')
+            test_i:is(fio.path.exists(console_sock), true, "file created")
+            check_ok(test_i, dir, 'enter', 'script', 1, nil, "Can't connect to")
+            fio.unlink(console_sock)
+        end)
+    end)
+
+    cleanup_instance(dir, 'script')
+    recursive_rmdir(dir)
+
+    if status == false then
+        print(("Error: %s"):format(err))
+        os.exit()
+    end
+end
+
 -- check basic help
 do
     local dir = fio.tempdir()
-- 
2.15.2 (Apple Git-101.1)