Include 437 (ERR_UNAVAILRESOURCE) as part of "nick in use" resolution upon connecting.

2 files changed, 8 insertions, 4 deletions

diff --git a/TODO b/TODO
index c65634f..6c90f83 100644
--- a/TODO
+++ b/TODO
@@ -43,3 +43,5 @@ BLABOUNCER/stdin functions to add:
 KICK not handled.
 
 Crash when requesting 30 hour replay.
+
+"too many clients, disconnecting and skipping loop iteration!" has been seen in the real world, e.g. Wed Jul 12 16:44:57 2023
diff --git a/message.c b/message.c
index 7067776..3eb35bd 100644
--- a/message.c
+++ b/message.c
@@ -748,10 +748,12 @@ int processservermessage(SSL *server_ssl, char *str, struct client *clients, int
       return 1;
     }
 
-    // Server 432 (ERR_ERRONEUSNICKNAME) or 433 (ERR_NICKNAMEINUSE) received?  See which nick we're on and try another.
-    // (But only if we're not already registered with the real IRC server.)
-    if ((strncmp(tokens[1], "432", strlen(tokens[1])) == 0 || strncmp(tokens[1], "433", strlen(tokens[1])) == 0) && !strlen(ircdstate->greeting004)) {
-      debugprint(DEBUG_SOME, "Server 432 (ERR_ERRONEUSNICKNAME) or 433 (ERR_NICKNAMEINUSE) found and it is: %s with length %zd!  Trying another nick...\n",
+    // Server 432 (ERR_ERRONEUSNICKNAME), 433 (ERR_NICKNAMEINUSE), or 437 (ERR_UNAVAILRESOURCE) received?  See which nick we're on and try another.
+    // (But only if we're not already registered with the real IRC server.  In particular 437 (ERR_UNAVAILRESOURCE) may be about a channel rather
+    // our nick, but if we're not registered yet then it's probably about our nick.)
+    if ((strncmp(tokens[1], "432", strlen(tokens[1])) == 0 || strncmp(tokens[1], "433", strlen(tokens[1])) == 0 || strncmp(tokens[1], "437", strlen(tokens[1])) == 0)
+        && !strlen(ircdstate->greeting004)) {
+      debugprint(DEBUG_SOME, "Server 432 (ERR_ERRONEUSNICKNAME), 433 (ERR_NICKNAMEINUSE), or 437 (ERR_UNAVAILRESOURCE) found and it is: %s with length %zd!  Trying another nick...\n",
                  tokens[1], strlen(tokens[1]));
 
       // Find the nick (its index in the nicks array) currently selected