Avoid prioritising MODE queries for channels with hyphens in their name

If a user has a large number of channels containing hyphens in their
names, the initial MODE queries will have the same high priority as any
PINGs, and so will block the PINGs from being sent, causing the
connection to time out due to a lack of PONGs received.

1 files changed, 28 insertions, 6 deletions

diff --git a/src/common/server.c b/src/common/server.c
index 3db0a963..f7fa8b96 100644
--- a/src/common/server.c
+++ b/src/common/server.c
@@ -200,13 +200,35 @@ tcp_send_len (server *serv, char *buf, int len)
 	}
 	else
 	{
-		/* WHO/MODE get the lowest priority */
-		if (g_ascii_strncasecmp (dbuf + 1, "WHO ", 4) == 0 ||
-		/* but only MODE queries, not changes */
-			(g_ascii_strncasecmp (dbuf + 1, "MODE", 4) == 0 &&
-			 strchr (dbuf, '-') == NULL &&
-			 strchr (dbuf, '+') == NULL))
+		/* WHO gets the lowest priority */
+		if (g_ascii_strncasecmp (dbuf + 1, "WHO ", 4) == 0)
 			dbuf[0] = 0;
+		/* as do MODE queries (but not changes) */
+		else if (g_ascii_strncasecmp (dbuf + 1, "MODE ", 5) == 0)
+		{
+			char *mode_str, *mode_str_end, *loc;
+			/* skip spaces before channel/nickname */
+			for (mode_str = dbuf + 5; *mode_str == ' '; ++mode_str);
+			/* skip over channel/nickname */
+			mode_str = strchr (mode_str, ' ');
+			if (mode_str)
+			{
+				/* skip spaces before mode string */
+				for (; *mode_str == ' '; ++mode_str);
+				/* find spaces after end of mode string */
+				mode_str_end = strchr (mode_str, ' ');
+				/* look for +/- within the mode string */
+				loc = strchr (mode_str, '-');
+				if (loc && (!mode_str_end || loc < mode_str_end))
+					goto keep_priority;
+				loc = strchr (mode_str, '+');
+				if (loc && (!mode_str_end || loc < mode_str_end))
+					goto keep_priority;
+			}
+			dbuf[0] = 0;
+keep_priority:
+			;
+		}
 	}
 
 	serv->outbound_queue = g_slist_append (serv->outbound_queue, dbuf);