Correctly recode client infomation to the slowlog when runing script (#805)

Currently when we are runing a script, we will passing a fake client.
So if the command executed in the script is recoded in the slowlog,
the client's ip:port and name information will be empty.

before:
```
127.0.0.1:6379> client setname myclient
OK
127.0.0.1:6379> config set slowlog-log-slower-than 0
OK
127.0.0.1:6379> eval "redis.call('ping')" 0
(nil)
127.0.0.1:6379> slowlog get 2
1) 1) (integer) 2
   2) (integer) 1721314289
   3) (integer) 96
   4) 1) "eval"
      2) "redis.call('ping')"
      3) "0"
   5) "127.0.0.1:61106"
   6) "myclient"
2) 1) (integer) 1
   2) (integer) 1721314289
   3) (integer) 4
   4) 1) "ping"
   5) ""
   6) ""
```

after:
```
127.0.0.1:6379> client setname myclient
OK
127.0.0.1:6379> config set slowlog-log-slower-than 0
OK
127.0.0.1:6379> eval "redis.call('ping')" 0
(nil)
127.0.0.1:6379> slowlog get 2
1) 1) (integer) 2
   2) (integer) 1721314371
   3) (integer) 53
   4) 1) "eval"
      2) "redis.call('ping')"
      3) "0"
   5) "127.0.0.1:51983"
   6) "myclient"
2) 1) (integer) 1
   2) (integer) 1721314371
   3) (integer) 1
   4) 1) "ping"
   5) "127.0.0.1:51983"
   6) "myclient"
```

Signed-off-by: Binbin <binloveplay1314@qq.com>

src/server.c

@@ -3275,6 +3275,13 @@ void slowlogPushCurrentCommand(client *c, struct serverCommand *cmd, ustime_t du
      * arguments. */
     robj **argv = c->original_argv ? c->original_argv : c->argv;
     int argc = c->original_argv ? c->original_argc : c->argc;
+
+    /* If a script is currently running, the client passed in is a
+     * fake client. Or the client passed in is the original client
+     * if this is a EVAL or alike, doesn't matter. In this case,
+     * use the original client to get the client information. */
+    c = scriptIsRunning() ? scriptGetCaller() : c;
+
     slowlogPushEntryIfNeeded(c, argv, argc, duration);
 }
 

tests/unit/slowlog.tcl

@@ -248,4 +248,42 @@ start_server {tags {"slowlog"} overrides {slowlog-log-slower-than 1000000}} {
         
         $rd close
     }
+
+    foreach is_eval {0 1} {
+        test "SLOWLOG - the commands in script are recorded normally - is_eval: $is_eval" {
+            if {$is_eval == 0} {
+                r function load replace "#!lua name=mylib \n redis.register_function('myfunc', function(KEYS, ARGS) server.call('ping') end)"
+            }
+
+            r client setname test-client
+            r config set slowlog-log-slower-than 0
+            r slowlog reset
+
+            if {$is_eval} {
+                r eval "server.call('ping')" 0
+            } else {
+                r fcall myfunc 0
+            }
+            set slowlog_resp [r slowlog get 2]
+            assert_equal 2 [llength $slowlog_resp]
+
+            # The first one is the script command, and the second one is the ping command executed in the script
+            # Each slowlog contains: id, timestamp, execution time, command array, ip:port, client name
+            set script_cmd [lindex $slowlog_resp 0]
+            set ping_cmd [lindex $slowlog_resp 1]
+
+            # Make sure the command are logged.
+            if {$is_eval} {
+                assert_equal {eval server.call('ping') 0} [lindex $script_cmd 3]
+            } else {
+                assert_equal {fcall myfunc 0} [lindex $script_cmd 3]
+            }
+            assert_equal {ping} [lindex $ping_cmd 3]
+
+            # Make sure the client info are the logged.
+            assert_equal [lindex $script_cmd 4] [lindex $ping_cmd 4]
+            assert_equal {test-client} [lindex $script_cmd 5]
+            assert_equal {test-client} [lindex $ping_cmd 5]
+        }
+    }
 }