tests: added test cases for sending HUP signal to nginx processes without the master process.

Signed-off-by: Yichun Zhang (agentzh) <yichun@openresty.com>

Author: zhuizhuhaomeng

t/163-signal.t

@@ -0,0 +1,51 @@
+# vi:ft=
+
+use Test::Nginx::Socket::Lua;
+
+plan tests => 2 * blocks();
+
+no_long_string();
+
+
+run_tests();
+
+__DATA__
+
+=== TEST 1: SIGHUP followed by SIGQUIT
+--- config
+    location = /t {
+        content_by_lua_block {
+            local pid = ngx.worker.pid()
+            os.execute("kill -HUP " .. pid)
+            ngx.sleep(0.01)
+
+            os.execute("kill -QUIT " .. pid)
+        }
+    }
+--- request
+GET /t
+--- ignore_response
+--- wait: 0.1
+--- error_log eval
+qr/\[notice\] \d+#\d+: exit$/
+--- no_error_log eval
+qr/\[notice\] \d+#\d+: reconfiguring/
+
+
+
+=== TEST 2: exit after receiving SIGHUP in single process mode
+--- config
+    location = /t {
+        content_by_lua_block {
+            local pid = ngx.worker.pid()
+            os.execute("kill -HUP " .. pid)
+        }
+    }
+--- request
+GET /t
+--- ignore_response
+--- wait: 0.1
+--- error_log eval
+qr/\[notice\] \d+#\d+: exit$/
+--- no_error_log eval
+qr/\[notice\] \d+#\d+: reconfiguring/