irc: add server option "anti_flood", remove server options "anti_flood_prio_{high|low}" (issue #1039)

The new option is set in milliseconds.

8 files changed, 317 insertions, 268 deletions

diff --git a/ChangeLog.adoc b/ChangeLog.adoc
index 569049d49..533ac7732 100644
--- a/ChangeLog.adoc
+++ b/ChangeLog.adoc
@@ -27,6 +27,7 @@ New features::
   * core: add number of processes in command `/sys waitpid`
   * core, alias, trigger: allow wildcard in commands `/bar`, `/item`, `/proxy`, `/alias` and `/trigger` (issue #1956)
   * buflist: jump to previous/next buffer displayed in buflist item with ctrl+wheel up/down on a buflist item (issue #1473)
+  * irc: add server option "anti_flood" (now in milliseconds), remove server options "anti_flood_prio_{high|low}" (issue #1039)
   * irc: add option irc.look.list_buffer
   * irc: change default value of server option "tls_priorities" to `NORMAL`
   * irc: add support of RGB colors in messages, add option irc.color.term_remap (issue #2025)
diff --git a/ReleaseNotes.adoc b/ReleaseNotes.adoc
index 9ca9bc3f6..eb5e214dc 100644
--- a/ReleaseNotes.adoc
+++ b/ReleaseNotes.adoc
@@ -14,6 +14,33 @@ For a complete list of changes, please look at ChangeLog.
 [[v4.2.0]]
 == Version 4.2.0 (under dev)
 
+[[v4.2.0_irc_anti_flood]]
+=== IRC anti-flood
+
+The anti-flood mechanism in IRC plugin has been improved and is now configured
+in milliseconds instead of seconds. +
+It is done with a single option `irc.server_default.anti_flood` (and same option
+in servers), which replaces both options `anti_flood_prio_high` and
+`anti_flood_prio_low`.
+
+The default value is 2000 (2 seconds), and for example if you want to set
+a delay of 0.5 seconds between your messages sent:
+
+----
+/set irc.server_default.anti_flood 500
+----
+
+When upgrading from an old WeeChat version, you'll see such messages, which are
+perfectly normal (they're displayed to warn you about unknown options, and then
+you have to set the new option if needed):
+
+----
+=!= | Warning: /home/user/.config/weechat/irc.conf, line 131: ignoring unknown option for section "server_default": anti_flood_prio_high = 2
+=!= | Warning: /home/user/.config/weechat/irc.conf, line 132: ignoring unknown option for section "server_default": anti_flood_prio_low = 2
+=!= | Warning: /home/user/.config/weechat/irc.conf, line 212: ignoring invalid value for option in section "server": libera.anti_flood_prio_high
+=!= | Warning: //home/user/.config/weechat/irc.conf, line 213: ignoring invalid value for option in section "server": libera.anti_flood_prio_low
+----
+
 [[v4.2.0_search_commands_history]]
 === Search in commands history
 
diff --git a/src/plugins/irc/irc-command.c b/src/plugins/irc/irc-command.c
index 8f6f165d5..61d977332 100644
--- a/src/plugins/irc/irc-command.c
+++ b/src/plugins/irc/irc-command.c
@@ -2366,11 +2366,13 @@ irc_command_quit_server (struct t_irc_server *server, const char *arguments)
     if (ptr_arg && ptr_arg[0])
     {
         msg = irc_server_get_default_msg (ptr_arg, server, NULL, NULL);
-        irc_server_sendf (server, 0, NULL, "QUIT :%s", msg);
+        irc_server_sendf (server, IRC_SERVER_SEND_OUTQ_PRIO_IMMEDIATE, NULL,
+                          "QUIT :%s", msg);
     }
     else
     {
-        irc_server_sendf (server, 0, NULL, "QUIT");
+        irc_server_sendf (server, IRC_SERVER_SEND_OUTQ_PRIO_IMMEDIATE, NULL,
+                          "QUIT");
     }
 
     if (msg)
@@ -5495,26 +5497,16 @@ irc_command_display_server (struct t_irc_server *server, int with_detail)
                             IRC_COLOR_CHAT_VALUE,
                             weechat_config_integer (server->options[IRC_SERVER_OPTION_CONNECTION_TIMEOUT]),
                             NG_("second", "seconds", weechat_config_integer (server->options[IRC_SERVER_OPTION_CONNECTION_TIMEOUT])));
-        /* anti_flood_prio_high */
-        if (weechat_config_option_is_null (server->options[IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_HIGH]))
-            weechat_printf (NULL, "  anti_flood_prio_high :   (%d %s)",
-                            IRC_SERVER_OPTION_INTEGER(server, IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_HIGH),
-                            NG_("second", "seconds", IRC_SERVER_OPTION_INTEGER(server, IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_HIGH)));
+        /* anti_flood */
+        if (weechat_config_option_is_null (server->options[IRC_SERVER_OPTION_ANTI_FLOOD]))
+            weechat_printf (NULL, "  anti_flood . . . . . :   (%d %s)",
+                            IRC_SERVER_OPTION_INTEGER(server, IRC_SERVER_OPTION_ANTI_FLOOD),
+                            NG_("second", "seconds", IRC_SERVER_OPTION_INTEGER(server, IRC_SERVER_OPTION_ANTI_FLOOD)));
         else
-            weechat_printf (NULL, "  anti_flood_prio_high : %s%d %s",
+            weechat_printf (NULL, "  anti_flood . . . . . : %s%d %s",
                             IRC_COLOR_CHAT_VALUE,
-                            weechat_config_integer (server->options[IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_HIGH]),
-                            NG_("second", "seconds", weechat_config_integer (server->options[IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_HIGH])));
-        /* anti_flood_prio_low */
-        if (weechat_config_option_is_null (server->options[IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_LOW]))
-            weechat_printf (NULL, "  anti_flood_prio_low. :   (%d %s)",
-                            IRC_SERVER_OPTION_INTEGER(server, IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_LOW),
-                            NG_("second", "seconds", IRC_SERVER_OPTION_INTEGER(server, IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_LOW)));
-        else
-            weechat_printf (NULL, "  anti_flood_prio_low. : %s%d %s",
-                            IRC_COLOR_CHAT_VALUE,
-                            weechat_config_integer (server->options[IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_LOW]),
-                            NG_("second", "seconds", weechat_config_integer (server->options[IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_LOW])));
+                            weechat_config_integer (server->options[IRC_SERVER_OPTION_ANTI_FLOOD]),
+                            NG_("second", "seconds", weechat_config_integer (server->options[IRC_SERVER_OPTION_ANTI_FLOOD])));
         /* away_check */
         if (weechat_config_option_is_null (server->options[IRC_SERVER_OPTION_AWAY_CHECK]))
             weechat_printf (NULL, "  away_check . . . . . :   (%d %s)",
@@ -6176,7 +6168,8 @@ IRC_COMMAND_CALLBACK(squit)
 
     WEECHAT_COMMAND_MIN_ARGS(2, "");
 
-    irc_server_sendf (ptr_server, 0, NULL, "SQUIT %s", argv_eol[1]);
+    irc_server_sendf (ptr_server, IRC_SERVER_SEND_OUTQ_PRIO_IMMEDIATE, NULL,
+                      "SQUIT %s", argv_eol[1]);
 
     return WEECHAT_RC_OK;
 }
diff --git a/src/plugins/irc/irc-config.c b/src/plugins/irc/irc-config.c
index 21606cfdb..6c9973497 100644
--- a/src/plugins/irc/irc-config.c
+++ b/src/plugins/irc/irc-config.c
@@ -179,12 +179,7 @@ struct t_config_option *irc_config_network_whois_double_nick = NULL;
 
 /* IRC config, server section */
 
-struct t_config_option *irc_config_server_default[IRC_SERVER_NUM_OPTIONS] = {
-    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
-    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
-    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
-    NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL,
-};
+struct t_config_option *irc_config_server_default[IRC_SERVER_NUM_OPTIONS];
 struct t_hook *irc_config_hook_config_nick_color_options = NULL;
 struct t_hook *irc_config_hook_config_chat_nick_colors = NULL;
 struct t_hashtable *irc_config_hashtable_display_join_message = NULL;
@@ -1102,6 +1097,13 @@ irc_config_server_default_change_cb (const void *pointer, void *data,
                         irc_server_set_nicks (ptr_server,
                                               weechat_config_string (option));
                         break;
+                    case IRC_SERVER_OPTION_ANTI_FLOOD:
+                        if (ptr_server->hook_timer_anti_flood)
+                        {
+                            irc_server_outqueue_timer_remove (ptr_server);
+                            irc_server_outqueue_timer_add (ptr_server);
+                        }
+                        break;
                     case IRC_SERVER_OPTION_AWAY_CHECK:
                     case IRC_SERVER_OPTION_AWAY_CHECK_MAX_NICKS:
                         if (IRC_SERVER_OPTION_INTEGER(
@@ -1401,6 +1403,13 @@ irc_config_server_change_cb (const void *pointer, void *data,
                         IRC_SERVER_OPTION_STRING(ptr_server,
                                                  IRC_SERVER_OPTION_NICKS));
                     break;
+                case IRC_SERVER_OPTION_ANTI_FLOOD:
+                    if (ptr_server->hook_timer_anti_flood)
+                    {
+                        irc_server_outqueue_timer_remove (ptr_server);
+                        irc_server_outqueue_timer_add (ptr_server);
+                    }
+                    break;
                 case IRC_SERVER_OPTION_AWAY_CHECK:
                 case IRC_SERVER_OPTION_AWAY_CHECK_MAX_NICKS:
                     if (IRC_SERVER_OPTION_INTEGER(ptr_server, IRC_SERVER_OPTION_AWAY_CHECK) > 0)
@@ -2503,32 +2512,19 @@ irc_config_server_new_option (struct t_config_file *config_file,
                 callback_change_data,
                 NULL, NULL, NULL);
             break;
-        case IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_HIGH:
+        case IRC_SERVER_OPTION_ANTI_FLOOD:
             new_option = weechat_config_new_option (
                 config_file, section,
                 option_name, "integer",
-                N_("anti-flood for high priority queue: number of seconds "
-                   "between two user messages or commands sent to IRC server "
-                   "(0 = no anti-flood)"),
-                NULL, 0, 60,
-                default_value, value,
-                null_value_allowed,
-                callback_check_value,
-                callback_check_value_pointer,
-                callback_check_value_data,
-                callback_change,
-                callback_change_pointer,
-                callback_change_data,
-                NULL, NULL, NULL);
-            break;
-        case IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_LOW:
-            new_option = weechat_config_new_option (
-                config_file, section,
-                option_name, "integer",
-                N_("anti-flood for low priority queue: number of seconds "
-                   "between two messages sent to IRC server (messages like "
-                   "automatic CTCP replies) (0 = no anti-flood)"),
-                NULL, 0, 60,
+                N_("delay in milliseconds between two messages sent to server "
+                   "(anti-flood); 0 = disable anti-flood and always send "
+                   "all messages immediately (not recommended as you can be "
+                   "quickly killed by the server); "
+                   "internally there are queues with different priorities: "
+                   "when connecting to the server all messages are sent "
+                   "immediately and your messages have higher priority than "
+                   "some automatic messages that are sent in background"),
+                NULL, 0, 60000,
                 default_value, value,
                 null_value_allowed,
                 callback_check_value,
@@ -3010,6 +3006,8 @@ irc_config_update_cb (const void *pointer, void *data,
 int
 irc_config_init ()
 {
+    int i;
+
     irc_config_hashtable_display_join_message = weechat_hashtable_new (
         32,
         WEECHAT_HASHTABLE_STRING,
@@ -3031,6 +3029,11 @@ irc_config_init ()
         WEECHAT_HASHTABLE_STRING,
         NULL, NULL);
 
+    for (i = 0; i < IRC_SERVER_NUM_OPTIONS; i++)
+    {
+        irc_config_server_default[i] = NULL;
+    }
+
     irc_config_file = weechat_config_new (IRC_CONFIG_PRIO_NAME,
                                           &irc_config_reload, NULL, NULL);
     if (!irc_config_file)
diff --git a/src/plugins/irc/irc-protocol.c b/src/plugins/irc/irc-protocol.c
index 68fe3249d..dc343d25a 100644
--- a/src/plugins/irc/irc-protocol.c
+++ b/src/plugins/irc/irc-protocol.c
@@ -2965,7 +2965,8 @@ IRC_PROTOCOL_CALLBACK(ping)
 
     str_params = irc_protocol_string_params (ctxt->params, 0, ctxt->num_params - 1);
 
-    irc_server_sendf (ctxt->server, 0, NULL, "PONG :%s", str_params);
+    irc_server_sendf (ctxt->server, IRC_SERVER_SEND_OUTQ_PRIO_IMMEDIATE, NULL,
+                      "PONG :%s", str_params);
 
     if (str_params)
         free (str_params);
@@ -7060,7 +7061,7 @@ IRC_PROTOCOL_CALLBACK(432)
         irc_server_set_nick (ctxt->server, alternate_nick);
 
         irc_server_sendf (
-            ctxt->server, 0, NULL,
+            ctxt->server, IRC_SERVER_SEND_OUTQ_PRIO_IMMEDIATE, NULL,
             "NICK %s%s",
             (ctxt->server->nick && strchr (ctxt->server->nick, ':')) ? ":" : "",
             ctxt->server->nick);
@@ -7111,7 +7112,7 @@ IRC_PROTOCOL_CALLBACK(433)
         irc_server_set_nick (ctxt->server, alternate_nick);
 
         irc_server_sendf (
-            ctxt->server, 0, NULL,
+            ctxt->server, IRC_SERVER_SEND_OUTQ_PRIO_IMMEDIATE, NULL,
             "NICK %s%s",
             (ctxt->server->nick && strchr (ctxt->server->nick, ':')) ? ":" : "",
             ctxt->server->nick);
@@ -7168,7 +7169,7 @@ IRC_PROTOCOL_CALLBACK(437)
             irc_server_set_nick (ctxt->server, alternate_nick);
 
             irc_server_sendf (
-                ctxt->server, 0, NULL,
+                ctxt->server, IRC_SERVER_SEND_OUTQ_PRIO_IMMEDIATE, NULL,
                 "NICK %s%s",
                 (ctxt->server->nick && strchr (ctxt->server->nick, ':')) ? ":" : "",
                 ctxt->server->nick);
diff --git a/src/plugins/irc/irc-server.c b/src/plugins/irc/irc-server.c
index 40f444b93..a1eea10ed 100644
--- a/src/plugins/irc/irc-server.c
+++ b/src/plugins/irc/irc-server.c
@@ -116,8 +116,7 @@ char *irc_server_options[IRC_SERVER_NUM_OPTIONS][2] =
   { "autorejoin",           "off"                     },
   { "autorejoin_delay",     "30"                      },
   { "connection_timeout",   "60"                      },
-  { "anti_flood_prio_high", "2"                       },
-  { "anti_flood_prio_low",  "2"                       },
+  { "anti_flood",           "2000"                    },
   { "away_check",           "0"                       },
   { "away_check_max_nicks", "25"                      },
   { "msg_kick",             ""                        },
@@ -153,6 +152,7 @@ int irc_fingerprint_digest_algos_size[IRC_FINGERPRINT_NUM_ALGOS] =
 { 160, 256, 512 };
 
 
+void irc_server_outqueue_send (struct t_irc_server *server);
 void irc_server_reconnect (struct t_irc_server *server);
 void irc_server_free_data (struct t_irc_server *server);
 void irc_server_autojoin_create_buffers (struct t_irc_server *server);
@@ -1697,6 +1697,7 @@ irc_server_alloc (const char *name)
     new_server->hook_fd = NULL;
     new_server->hook_timer_connection = NULL;
     new_server->hook_timer_sasl = NULL;
+    new_server->hook_timer_anti_flood = NULL;
     new_server->sasl_scram_client_first = NULL;
     new_server->sasl_scram_salted_pwd = NULL;
     new_server->sasl_scram_salted_pwd_size = 0;
@@ -1768,7 +1769,6 @@ irc_server_alloc (const char *name)
     new_server->lag_last_refresh = 0;
     new_server->cmd_list_regexp = NULL;
     new_server->list = irc_list_alloc (new_server);
-    new_server->last_user_message = 0;
     new_server->last_away_check = 0;
     new_server->last_data_purge = 0;
     for (i = 0; i < IRC_SERVER_NUM_OUTQUEUES_PRIO; i++)
@@ -2323,6 +2323,8 @@ irc_server_free_data (struct t_irc_server *server)
         weechat_unhook (server->hook_timer_connection);
     if (server->hook_timer_sasl)
         weechat_unhook (server->hook_timer_sasl);
+    if (server->hook_timer_anti_flood)
+        weechat_unhook (server->hook_timer_anti_flood);
     irc_server_free_sasl_data (server);
     if (server->unterminated_message)
         free (server->unterminated_message);
@@ -2798,101 +2800,188 @@ irc_server_get_tags_to_send (const char *tags)
 }
 
 /*
- * Sends a message from out queue.
+ * Checks if all out queues are empty.
+ *
+ * Returns:
+ *   1: all out queues are empty
+ *   0: at least one out queue contains a message
+ */
+
+int
+irc_server_outqueue_all_empty (struct t_irc_server *server)
+{
+    int priority;
+
+    for (priority = 0; priority < IRC_SERVER_NUM_OUTQUEUES_PRIO; priority++)
+    {
+        if (server->outqueue[priority])
+            return 0;
+    }
+    return 1;
+}
+
+/*
+ * Timer called to send out queue (anti-flood).
+ */
+
+int
+irc_server_outqueue_timer_cb (const void *pointer, void *data, int remaining_calls)
+{
+    struct t_irc_server *server;
+
+    /* make C compiler happy */
+    (void) data;
+    (void) remaining_calls;
+
+    server = (struct t_irc_server *)pointer;
+
+    irc_server_outqueue_send (server);
+
+    return WEECHAT_RC_OK;
+}
+
+/*
+ * Removes anti-flood timer form a server (if set).
  */
 
 void
-irc_server_outqueue_send (struct t_irc_server *server)
+irc_server_outqueue_timer_remove (struct t_irc_server *server)
+{
+    if (!server)
+        return;
+
+    if (server->hook_timer_anti_flood)
+    {
+        weechat_unhook (server->hook_timer_anti_flood);
+        server->hook_timer_anti_flood = NULL;
+    }
+}
+
+/*
+ * Adds anti-flood timer in a server (removes it first if already set).
+ */
+
+void
+irc_server_outqueue_timer_add (struct t_irc_server *server)
+{
+    if (!server)
+        return;
+
+    if (server->hook_timer_anti_flood)
+        irc_server_outqueue_timer_remove (server);
+
+    server->hook_timer_anti_flood = weechat_hook_timer (
+        IRC_SERVER_OPTION_INTEGER(server, IRC_SERVER_OPTION_ANTI_FLOOD),
+        0, 0,
+        &irc_server_outqueue_timer_cb,
+        server, NULL);
+}
+
+/*
+ * Sends one message from out queue.
+ */
+
+void
+irc_server_outqueue_send_one_msg (struct t_irc_server *server,
+                                  struct t_irc_outqueue *message)
 {
-    time_t time_now;
     char *pos, *tags_to_send;
-    int priority, anti_flood;
 
-    time_now = time (NULL);
+    if (!server || !message)
+        return;
 
-    /* detect if system clock has been changed (now lower than before) */
-    if (server->last_user_message > time_now)
-        server->last_user_message = time_now;
+    if (message->message_before_mod)
+    {
+        pos = strchr (message->message_before_mod, '\r');
+        if (pos)
+            pos[0] = '\0';
+        irc_raw_print (server, IRC_RAW_FLAG_SEND, message->message_before_mod);
+        if (pos)
+            pos[0] = '\r';
+    }
 
-    for (priority = 0; priority < IRC_SERVER_NUM_OUTQUEUES_PRIO; priority++)
+    if (message->message_after_mod)
     {
-        switch (priority)
+        pos = strchr (message->message_after_mod, '\r');
+        if (pos)
+            pos[0] = '\0';
+
+        irc_raw_print (
+            server,
+            IRC_RAW_FLAG_SEND | ((message->modified) ? IRC_RAW_FLAG_MODIFIED : 0),
+            message->message_after_mod);
+
+        /* send signal with command that will be sent to server */
+        (void) irc_server_send_signal (
+            server,
+            "irc_out",
+            message->command,
+            message->message_after_mod,
+            NULL);
+        tags_to_send = irc_server_get_tags_to_send (message->tags);
+        (void) irc_server_send_signal (
+            server,
+            "irc_outtags",
+            message->command,
+            message->message_after_mod,
+            (tags_to_send) ? tags_to_send : "");
+        if (tags_to_send)
+            free (tags_to_send);
+
+        if (pos)
+            pos[0] = '\r';
+
+        /* send command */
+        irc_server_send (server,
+                         message->message_after_mod,
+                         strlen (message->message_after_mod));
+
+        /* start redirection if redirect is set */
+        if (message->redirect)
         {
-            case 0: /* immediate send */
-                anti_flood = 0;
-                break;
-            case 1: /* high priority */
-                anti_flood = IRC_SERVER_OPTION_INTEGER(
-                    server, IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_HIGH);
-                break;
-            default: /* low priority */
-                anti_flood = IRC_SERVER_OPTION_INTEGER(
-                    server, IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_LOW);
-                break;
+            irc_redirect_init_command (message->redirect,
+                                       message->message_after_mod);
         }
-        if (server->outqueue[priority]
-            && (time_now >= server->last_user_message + anti_flood))
-        {
-            if (server->outqueue[priority]->message_before_mod)
-            {
-                pos = strchr (server->outqueue[priority]->message_before_mod,
-                              '\r');
-                if (pos)
-                    pos[0] = '\0';
-                irc_raw_print (server, IRC_RAW_FLAG_SEND,
-                               server->outqueue[priority]->message_before_mod);
-                if (pos)
-                    pos[0] = '\r';
-            }
-            if (server->outqueue[priority]->message_after_mod)
-            {
-                pos = strchr (server->outqueue[priority]->message_after_mod,
-                              '\r');
-                if (pos)
-                    pos[0] = '\0';
-
-                irc_raw_print (server, IRC_RAW_FLAG_SEND |
-                               ((server->outqueue[priority]->modified) ? IRC_RAW_FLAG_MODIFIED : 0),
-                               server->outqueue[priority]->message_after_mod);
-
-                /* send signal with command that will be sent to server */
-                (void) irc_server_send_signal (
-                    server, "irc_out",
-                    server->outqueue[priority]->command,
-                    server->outqueue[priority]->message_after_mod,
-                    NULL);
-                tags_to_send = irc_server_get_tags_to_send (
-                    server->outqueue[priority]->tags);
-                (void) irc_server_send_signal (
-                    server, "irc_outtags",
-                    server->outqueue[priority]->command,
-                    server->outqueue[priority]->message_after_mod,
-                    (tags_to_send) ? tags_to_send : "");
-                if (tags_to_send)
-                    free (tags_to_send);
+    }
+}
 
-                if (pos)
-                    pos[0] = '\r';
+/*
+ * Sends one or multiple message from out queues, by order of priority
+ * (immediate/high/low), then from oldest message to newest in queue.
+ */
 
-                /* send command */
-                irc_server_send (
-                    server, server->outqueue[priority]->message_after_mod,
-                    strlen (server->outqueue[priority]->message_after_mod));
-                server->last_user_message = time_now;
+void
+irc_server_outqueue_send (struct t_irc_server *server)
+{
+    int priority, anti_flood;
 
-                /* start redirection if redirect is set */
-                if (server->outqueue[priority]->redirect)
-                {
-                    irc_redirect_init_command (
-                        server->outqueue[priority]->redirect,
-                        server->outqueue[priority]->message_after_mod);
-                }
-            }
-            irc_server_outqueue_free (server, priority,
-                                      server->outqueue[priority]);
+    if (irc_server_outqueue_all_empty (server))
+    {
+        irc_server_outqueue_timer_remove (server);
+        return;
+    }
+
+    anti_flood = IRC_SERVER_OPTION_INTEGER(server, IRC_SERVER_OPTION_ANTI_FLOOD);
+
+    for (priority = 0; priority < IRC_SERVER_NUM_OUTQUEUES_PRIO; priority++)
+    {
+        if (!server->outqueue[priority])
+            continue;
+
+        irc_server_outqueue_send_one_msg (server, server->outqueue[priority]);
+        irc_server_outqueue_free (server, priority, server->outqueue[priority]);
+
+        /*
+         * continue to send for immediate priority (= 0),
+         * exit loop now for high/low priorities (> 0) if anti flood is enabled
+         */
+        if ((priority > 0) && (anti_flood > 0))
             break;
-        }
     }
+
+    /* schedule next send if anti-flood is enabled */
+    if ((anti_flood > 0) && !server->hook_timer_anti_flood)
+        irc_server_outqueue_timer_add (server);
 }
 
 /*
@@ -2903,13 +2992,9 @@ irc_server_outqueue_send (struct t_irc_server *server)
  * queue_msg is priority:
  *   1 = higher priority, for user messages
  *   2 = lower priority, for other messages (like auto reply to CTCP queries)
- *
- * Returns:
- *   1: OK
- *   0: error
  */
 
-int
+void
 irc_server_send_one_msg (struct t_irc_server *server, int flags,
                          const char *message, const char *nick,
                          const char *command, const char *channel,
@@ -2919,13 +3004,9 @@ irc_server_send_one_msg (struct t_irc_server *server, int flags,
     const char *ptr_msg, *ptr_chan_nick;
     char *new_msg, *pos, *tags_to_send, *msg_encoded;
     char str_modifier[128], modifier_data[1024];
-    int rc, queue_msg, add_to_queue, first_message, anti_flood;
-    int pos_channel, pos_text, pos_encode;
-    time_t time_now;
+    int first_message, queue_msg, pos_channel, pos_text, pos_encode;
     struct t_irc_redirect *ptr_redirect;
 
-    rc = 1;
-
     /* run modifier "irc_out_xxx" */
     snprintf (str_modifier, sizeof (str_modifier),
               "irc_out_%s",
@@ -3017,7 +3098,7 @@ irc_server_send_one_msg (struct t_irc_server *server, int flags,
         if (msg_encoded)
             ptr_msg = msg_encoded;
 
-        while (rc && ptr_msg && ptr_msg[0])
+        while (ptr_msg && ptr_msg[0])
         {
             pos = strchr (ptr_msg, '\n');
             if (pos)
@@ -3025,101 +3106,41 @@ irc_server_send_one_msg (struct t_irc_server *server, int flags,
 
             snprintf (buffer, sizeof (buffer), "%s\r\n", ptr_msg);
 
-            /* anti-flood: look whether we should queue outgoing message or not */
-            time_now = time (NULL);
-
-            /* detect if system clock has been changed (now lower than before) */
-            if (server->last_user_message > time_now)
-                server->last_user_message = time_now;
-
-            /* get queue from flags */
-            queue_msg = 0;
             if (flags & IRC_SERVER_SEND_OUTQ_PRIO_IMMEDIATE)
-                queue_msg = 1;
+                queue_msg = 0;
             else if (flags & IRC_SERVER_SEND_OUTQ_PRIO_HIGH)
-                queue_msg = 2;
+                queue_msg = 1;
             else if (flags & IRC_SERVER_SEND_OUTQ_PRIO_LOW)
-                queue_msg = 3;
-
-            switch (queue_msg - 1)
-            {
-                case 0:
-                    anti_flood = 0;
-                    break;
-                case 1:
-                    anti_flood = IRC_SERVER_OPTION_INTEGER(
-                        server, IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_HIGH);
-                    break;
-                default:
-                    anti_flood = IRC_SERVER_OPTION_INTEGER(
-                        server, IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_LOW);
-                    break;
-            }
-
-            add_to_queue = 0;
-            if ((queue_msg > 0)
-                && (server->outqueue[queue_msg - 1]
-                    || ((anti_flood > 0)
-                        && (time_now - server->last_user_message < anti_flood))))
+                queue_msg = 2;
+            else
             {
-                add_to_queue = queue_msg;
+                /*
+                 * if connected to server (message 001 received), consider
+                 * it's low priority (otherwise send immediately)
+                 */
+                queue_msg = (server->is_connected) ? 2 : 0;
             }
 
             tags_to_send = irc_server_get_tags_to_send (tags);
 
             ptr_redirect = irc_redirect_search_available (server);
 
-            if (add_to_queue > 0)
-            {
-                /* queue message (do not send anything now) */
-                irc_server_outqueue_add (server, add_to_queue - 1, command,
-                                         (new_msg && first_message) ? message : NULL,
-                                         buffer,
-                                         (new_msg) ? 1 : 0,
-                                         tags_to_send,
-                                         ptr_redirect);
-                /* mark redirect as "used" */
-                if (ptr_redirect)
-                    ptr_redirect->assigned_to_command = 1;
-            }
-            else
-            {
-                if (first_message)
-                {
-                    irc_raw_print (server, IRC_RAW_FLAG_SEND, message);
-                }
-                if (new_msg)
-                {
-                    irc_raw_print (server,
-                                   IRC_RAW_FLAG_SEND | IRC_RAW_FLAG_MODIFIED,
-                                   ptr_msg);
-                }
+            /* queue message (do not send anything now) */
+            irc_server_outqueue_add (server,
+                                     queue_msg,
+                                     command,
+                                     (new_msg && first_message) ? message : NULL,
+                                     buffer,
+                                     (new_msg) ? 1 : 0,
+                                     tags_to_send,
+                                     ptr_redirect);
 
-                /* send signal with command that will be sent to server */
-                (void) irc_server_send_signal (
-                    server, "irc_out",
-                    (command) ? command : "unknown",
-                    ptr_msg,
-                    NULL);
-                (void) irc_server_send_signal (
-                    server, "irc_outtags",
-                    (command) ? command : "unknown",
-                    ptr_msg,
-                    (tags_to_send) ? tags_to_send : "");
-
-                if (irc_server_send (server, buffer, strlen (buffer)) <= 0)
-                    rc = 0;
-                else
-                {
-                    if (queue_msg > 0)
-                        server->last_user_message = time_now;
-                }
-                if (ptr_redirect)
-                    irc_redirect_init_command (ptr_redirect, buffer);
-            }
+            /* mark redirect as "used" */
+            if (ptr_redirect)
+                ptr_redirect->assigned_to_command = 1;
 
             if (tags_to_send)
-                    free (tags_to_send);
+                free (tags_to_send);
 
             if (pos)
             {
@@ -3142,8 +3163,6 @@ irc_server_send_one_msg (struct t_irc_server *server, int flags,
 
     if (new_msg)
         free (new_msg);
-
-    return rc;
 }
 
 /*
@@ -3293,9 +3312,8 @@ irc_server_sendf (struct t_irc_server *server, int flags, const char *tags,
                 str_message = weechat_hashtable_get (hashtable, hash_key);
                 if (!str_message)
                     break;
-                if (!irc_server_send_one_msg (server, flags, str_message,
-                                              nick, command, channel, tags))
-                    break;
+                irc_server_send_one_msg (server, flags, str_message,
+                                         nick, command, channel, tags);
                 if (!multiline && list_messages)
                 {
                     snprintf (hash_key, sizeof (hash_key), "args%d", number);
@@ -3319,6 +3337,17 @@ irc_server_sendf (struct t_irc_server *server, int flags, const char *tags,
         free (new_msg);
     free (vbuffer);
 
+    /* send all messages with "immediate" priority */
+    while (server->outqueue[0])
+    {
+        irc_server_outqueue_send_one_msg (server, server->outqueue[0]);
+        irc_server_outqueue_free (server, 0, server->outqueue[0]);
+    }
+
+    /* send any other messages, if any, possibly with anti-flood */
+    if (!server->hook_timer_anti_flood)
+        irc_server_outqueue_send (server);
+
     return list_messages;
 }
 
@@ -4008,15 +4037,15 @@ irc_server_timer_cb (const void *pointer, void *data, int remaining_calls)
             if (!ptr_server->is_connected)
                 continue;
 
-            /* send queued messages */
-            irc_server_outqueue_send (ptr_server);
-
             /* check for lag */
             if ((weechat_config_integer (irc_config_network_lag_check) > 0)
                 && (ptr_server->lag_check_time.tv_sec == 0)
                 && (current_time >= ptr_server->lag_next_check))
             {
-                irc_server_sendf (ptr_server, 0, NULL, "PING %s",
+                irc_server_sendf (ptr_server,
+                                  IRC_SERVER_SEND_OUTQ_PRIO_IMMEDIATE,
+                                  NULL,  /* tags */
+                                  "PING %s",
                                   (ptr_server->current_address) ?
                                   ptr_server->current_address : "weechat");
                 gettimeofday (&(ptr_server->lag_check_time), NULL);
@@ -4202,6 +4231,12 @@ irc_server_close_connection (struct t_irc_server *server)
     }
     irc_server_free_sasl_data (server);
 
+    if (server->hook_timer_anti_flood)
+    {
+        weechat_unhook (server->hook_timer_anti_flood);
+        server->hook_timer_anti_flood = NULL;
+    }
+
     if (server->hook_fd)
     {
         weechat_unhook (server->hook_fd);
@@ -4364,7 +4399,7 @@ irc_server_login (struct t_irc_server *server)
     if (password && password[0])
     {
         irc_server_sendf (
-            server, 0, NULL,
+            server, IRC_SERVER_SEND_OUTQ_PRIO_IMMEDIATE, NULL,
             "PASS %s%s",
             ((password[0] == ':') || (strchr (password, ' '))) ? ":" : "",
             password);
@@ -4384,18 +4419,19 @@ irc_server_login (struct t_irc_server *server)
 
     if (irc_server_sasl_enabled (server) || (capabilities && capabilities[0]))
     {
-        irc_server_sendf (server, 0, NULL, "CAP LS " IRC_SERVER_VERSION_CAP);
+        irc_server_sendf (server, IRC_SERVER_SEND_OUTQ_PRIO_IMMEDIATE, NULL,
+                          "CAP LS " IRC_SERVER_VERSION_CAP);
     }
 
     username2 = (username && username[0]) ?
         weechat_string_replace (username, " ", "_") : strdup ("weechat");
     irc_server_sendf (
-        server, 0, NULL,
+        server, IRC_SERVER_SEND_OUTQ_PRIO_IMMEDIATE, NULL,
         "NICK %s%s",
         (server->nick && strchr (server->nick, ':')) ? ":" : "",
         server->nick);
     irc_server_sendf (
-        server, 0, NULL,
+        server, IRC_SERVER_SEND_OUTQ_PRIO_IMMEDIATE, NULL,
         "USER %s 0 * :%s",
         (username2) ? username2 : "weechat",
         (realname && realname[0]) ? realname : ((username2) ? username2 : "weechat"));
@@ -6482,6 +6518,7 @@ irc_server_hdata_server_cb (const void *pointer, void *data,
         WEECHAT_HDATA_VAR(struct t_irc_server, hook_fd, POINTER, 0, NULL, "hook");
         WEECHAT_HDATA_VAR(struct t_irc_server, hook_timer_connection, POINTER, 0, NULL, "hook");
         WEECHAT_HDATA_VAR(struct t_irc_server, hook_timer_sasl, POINTER, 0, NULL, "hook");
+        WEECHAT_HDATA_VAR(struct t_irc_server, hook_timer_anti_flood, POINTER, 0, NULL, "hook");
         WEECHAT_HDATA_VAR(struct t_irc_server, sasl_scram_client_first, STRING, 0, NULL, NULL);
         WEECHAT_HDATA_VAR(struct t_irc_server, sasl_scram_salted_pwd, OTHER, 0, NULL, NULL);
         WEECHAT_HDATA_VAR(struct t_irc_server, sasl_scram_salted_pwd_size, INTEGER, 0, NULL, NULL);
@@ -6542,7 +6579,6 @@ irc_server_hdata_server_cb (const void *pointer, void *data,
         WEECHAT_HDATA_VAR(struct t_irc_server, lag_last_refresh, TIME, 0, NULL, NULL);
         WEECHAT_HDATA_VAR(struct t_irc_server, cmd_list_regexp, POINTER, 0, NULL, NULL);
         WEECHAT_HDATA_VAR(struct t_irc_server, list, POINTER, 0, NULL, "irc_list");
-        WEECHAT_HDATA_VAR(struct t_irc_server, last_user_message, TIME, 0, NULL, NULL);
         WEECHAT_HDATA_VAR(struct t_irc_server, last_away_check, TIME, 0, NULL, NULL);
         WEECHAT_HDATA_VAR(struct t_irc_server, last_data_purge, TIME, 0, NULL, NULL);
         WEECHAT_HDATA_VAR(struct t_irc_server, outqueue, POINTER, 0, NULL, NULL);
@@ -6711,11 +6747,8 @@ irc_server_add_to_infolist (struct t_infolist *infolist,
     if (!weechat_infolist_new_var_integer (ptr_item, "connection_timeout",
                                            IRC_SERVER_OPTION_INTEGER(server, IRC_SERVER_OPTION_CONNECTION_TIMEOUT)))
         return 0;
-    if (!weechat_infolist_new_var_integer (ptr_item, "anti_flood_prio_high",
-                                           IRC_SERVER_OPTION_INTEGER(server, IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_HIGH)))
-        return 0;
-    if (!weechat_infolist_new_var_integer (ptr_item, "anti_flood_prio_low",
-                                           IRC_SERVER_OPTION_INTEGER(server, IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_LOW)))
+    if (!weechat_infolist_new_var_integer (ptr_item, "anti_flood",
+                                           IRC_SERVER_OPTION_INTEGER(server, IRC_SERVER_OPTION_ANTI_FLOOD)))
         return 0;
     if (!weechat_infolist_new_var_integer (ptr_item, "away_check",
                                            IRC_SERVER_OPTION_INTEGER(server, IRC_SERVER_OPTION_AWAY_CHECK)))
@@ -6920,8 +6953,6 @@ irc_server_add_to_infolist (struct t_infolist *infolist,
         return 0;
     if (!weechat_infolist_new_var_integer (ptr_item, "disable_autojoin", server->disable_autojoin))
         return 0;
-    if (!weechat_infolist_new_var_time (ptr_item, "last_user_message", server->last_user_message))
-        return 0;
     if (!weechat_infolist_new_var_time (ptr_item, "last_away_check", server->last_away_check))
         return 0;
     if (!weechat_infolist_new_var_time (ptr_item, "last_data_purge", server->last_data_purge))
@@ -7185,20 +7216,13 @@ irc_server_print_log ()
         else
             weechat_log_printf ("  connection_timeout. . . . : %d",
                                 weechat_config_integer (ptr_server->options[IRC_SERVER_OPTION_CONNECTION_TIMEOUT]));
-        /* anti_flood_prio_high */
-        if (weechat_config_option_is_null (ptr_server->options[IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_HIGH]))
-            weechat_log_printf ("  anti_flood_prio_high. . . : null (%d)",
-                                IRC_SERVER_OPTION_INTEGER(ptr_server, IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_HIGH));
-        else
-            weechat_log_printf ("  anti_flood_prio_high. . . : %d",
-                                weechat_config_integer (ptr_server->options[IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_HIGH]));
-        /* anti_flood_prio_low */
-        if (weechat_config_option_is_null (ptr_server->options[IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_LOW]))
-            weechat_log_printf ("  anti_flood_prio_low . . . : null (%d)",
-                                IRC_SERVER_OPTION_INTEGER(ptr_server, IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_LOW));
+        /* anti_flood */
+        if (weechat_config_option_is_null (ptr_server->options[IRC_SERVER_OPTION_ANTI_FLOOD]))
+            weechat_log_printf ("  anti_flood. . . . . . . . : null (%d)",
+                                IRC_SERVER_OPTION_INTEGER(ptr_server, IRC_SERVER_OPTION_ANTI_FLOOD));
         else
-            weechat_log_printf ("  anti_flood_prio_low . . . : %d",
-                                weechat_config_integer (ptr_server->options[IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_LOW]));
+            weechat_log_printf ("  anti_flood. . . . . . . . : %d",
+                                weechat_config_integer (ptr_server->options[IRC_SERVER_OPTION_ANTI_FLOOD]));
         /* away_check */
         if (weechat_config_option_is_null (ptr_server->options[IRC_SERVER_OPTION_AWAY_CHECK]))
             weechat_log_printf ("  away_check. . . . . . . . : null (%d)",
@@ -7254,6 +7278,7 @@ irc_server_print_log ()
         weechat_log_printf ("  hook_fd . . . . . . . . . : 0x%lx", ptr_server->hook_fd);
         weechat_log_printf ("  hook_timer_connection . . : 0x%lx", ptr_server->hook_timer_connection);
         weechat_log_printf ("  hook_timer_sasl . . . . . : 0x%lx", ptr_server->hook_timer_sasl);
+        weechat_log_printf ("  hook_timer_anti_flood . . : 0x%lx", ptr_server->hook_timer_anti_flood);
         weechat_log_printf ("  sasl_scram_client_first . : '%s'",  ptr_server->sasl_scram_client_first);
         weechat_log_printf ("  sasl_scram_salted_pwd . . : (hidden)");
         weechat_log_printf ("  sasl_scram_salted_pwd_size: %d",    ptr_server->sasl_scram_salted_pwd_size);
@@ -7331,7 +7356,6 @@ irc_server_print_log ()
             weechat_log_printf ("    channels. . . . . . . . : 0x%lx", ptr_server->list->channels);
             weechat_log_printf ("    filter_channels . . . . : 0x%lx", ptr_server->list->filter_channels);
         }
-        weechat_log_printf ("  last_user_message . . . . : %lld",  (long long)ptr_server->last_user_message);
         weechat_log_printf ("  last_away_check . . . . . : %lld",  (long long)ptr_server->last_away_check);
         weechat_log_printf ("  last_data_purge . . . . . : %lld",  (long long)ptr_server->last_data_purge);
         for (i = 0; i < IRC_SERVER_NUM_OUTQUEUES_PRIO; i++)
diff --git a/src/plugins/irc/irc-server.h b/src/plugins/irc/irc-server.h
index 2b6b652d7..1e807a186 100644
--- a/src/plugins/irc/irc-server.h
+++ b/src/plugins/irc/irc-server.h
@@ -83,8 +83,7 @@ enum t_irc_server_option
     IRC_SERVER_OPTION_AUTOREJOIN,    /* auto rejoin channels when kicked     */
     IRC_SERVER_OPTION_AUTOREJOIN_DELAY,     /* delay before auto rejoin      */
     IRC_SERVER_OPTION_CONNECTION_TIMEOUT,   /* timeout for connection        */
-    IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_HIGH, /* anti-flood (high priority)    */
-    IRC_SERVER_OPTION_ANTI_FLOOD_PRIO_LOW,  /* anti-flood (low priority)     */
+    IRC_SERVER_OPTION_ANTI_FLOOD,           /* anti-flood (in ms)            */
     IRC_SERVER_OPTION_AWAY_CHECK,           /* delay between away checks     */
     IRC_SERVER_OPTION_AWAY_CHECK_MAX_NICKS, /* max nicks for away check      */
     IRC_SERVER_OPTION_MSG_KICK,             /* default kick message          */
@@ -217,6 +216,7 @@ struct t_irc_server
     struct t_hook *hook_fd;         /* hook for server socket                */
     struct t_hook *hook_timer_connection; /* timer for connection            */
     struct t_hook *hook_timer_sasl; /* timer for SASL authentication         */
+    struct t_hook *hook_timer_anti_flood; /* anti-flood timer                */
     char *sasl_scram_client_first;  /* first message sent for SASL SCRAM     */
     char *sasl_scram_salted_pwd;    /* salted password for SASL SCRAM        */
     int sasl_scram_salted_pwd_size; /* size of salted password for SASL SCRAM*/
@@ -282,7 +282,6 @@ struct t_irc_server
     time_t lag_last_refresh;        /* last refresh of lag item              */
     regex_t *cmd_list_regexp;       /* compiled Regular Expression for /list */
     struct t_irc_list *list;        /* /list buffer management               */
-    time_t last_user_message;       /* time of last user message (anti flood)*/
     time_t last_away_check;         /* time of last away check on server     */
     time_t last_data_purge;         /* time of last purge (some hashtables)  */
     struct t_irc_outqueue *outqueue[IRC_SERVER_NUM_OUTQUEUES_PRIO];
@@ -413,6 +412,8 @@ extern int irc_server_send_signal (struct t_irc_server *server,
                                    const char *full_message,
                                    const char *tags);
 extern void irc_server_set_send_default_tags (const char *tags);
+extern void irc_server_outqueue_timer_remove (struct t_irc_server *server);
+extern void irc_server_outqueue_timer_add (struct t_irc_server *server);
 extern struct t_arraylist *irc_server_sendf (struct t_irc_server *server,
                                              int flags,
                                              const char *tags,
diff --git a/src/plugins/irc/irc-upgrade.c b/src/plugins/irc/irc-upgrade.c
index fa82d20e8..8745477d1 100644
--- a/src/plugins/irc/irc-upgrade.c
+++ b/src/plugins/irc/irc-upgrade.c
@@ -663,7 +663,6 @@ irc_upgrade_read_cb (const void *pointer, void *data,
                         memcpy (&(irc_upgrade_current_server->lag_check_time), buf, size);
                     irc_upgrade_current_server->lag_next_check = weechat_infolist_time (infolist, "lag_next_check");
                     irc_upgrade_current_server->lag_last_refresh = weechat_infolist_time (infolist, "lag_last_refresh");
-                    irc_upgrade_current_server->last_user_message = weechat_infolist_time (infolist, "last_user_message");
                     irc_upgrade_current_server->last_away_check = weechat_infolist_time (infolist, "last_away_check");
                     irc_upgrade_current_server->last_data_purge = weechat_infolist_time (infolist, "last_data_purge");
                 }