Browse packets no longer sent after reload

[michaelrsweet]

Version: 1.2.0
CUPS.org User: twaugh.redhat

Reloading cupsd (by sending it SIGHUP) causes browse packets to be stopped.

See RH Bugzilla bug #191217:

https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=191217

[michaelrsweet]

CUPS.org User: mike

Everything looks OK here, looking into it some more...

[michaelrsweet]

CUPS.org User: mike

I can't reproduce this at all - can you get a cupsd.conf and error_log file from the user?

[michaelrsweet]

CUPS.org User: twaugh.redhat

https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=191217 now has the cupsd.conf used, as well as an error_log snippet. The important line is:

E [09/May/2006:14:01:19 -0600] cupsdSendBrowseList: sendto failed for browser 1 - Bad file descriptor.

It seems like this is what happens:

In main.c at line 611, cupsdStopServer() calls cupsdStopBrowsing() which closes the browse socket and sets BrowseSocket to -1.

Then, from main.c:617, while reading configuration, NumBrowsers gets set to 1. But later during cupsdReadConfiguration() (conf.c:938), the scheduler attempts to send 'delete' browse messages from cupsdDeletePrinter() (printers.c:681).

This fails, because BrowseSocket == -1, and so at dirsvc.c:2608 we decrement NumBrowsers back to 0.

Later, in cupsdStartBrowsing, we do open the browse socket -- but NumBrowsers is still 0 so it never gets used.

Perhaps the key to reproducing this problem is having both 'BrowseDeny All' and 'BrowseAddress @Local' in cupsd.conf.

[michaelrsweet]

CUPS.org User: twaugh.redhat

Actually you need a specific 'BrowseAddress' network mask like 192.168.1.255 to trigger this.

[michaelrsweet]

CUPS.org User: twaugh.redhat

Attached is a fix that works for me.

[michaelrsweet]

CUPS.org User: mike

Actually, I'm opting to localize the check to cupsdSendBrowseDelete(), since we want to disable browsing if BrowseSocket is -1 after a successful startup.

I also added corresponding checks for SLP as well...

Let me know if this doesn't work for you...

(And BTW, thanks for the clear debugging into the cause!)

[michaelrsweet]

"cups-str1670.patch":

--- cups-1.2.x/scheduler/dirsvc.c.str1670 2006-05-18 13:48:42.000000000 +0100
+++ cups-1.2.x/scheduler/dirsvc.c 2006-05-18 13:49:45.000000000 +0100
@@ -2596,7 +2596,8 @@
cupsdLogMessage(CUPSD_LOG_DEBUG2,
"cupsdSendBrowseList: (%d bytes) %s", bytes, packet);

•  if (sendto(BrowseSocket, packet, bytes, 0,
  

•  if (BrowseSocket != -1 &&
  

• sendto(BrowseSocket, packet, bytes, 0,
   (struct sockaddr *)&(b->to),
   sizeof(struct sockaddr_in)) <= 0)
  

  {

[michaelrsweet]

"str1670.patch":

Index: dirsvc.c

--- dirsvc.c (revision 5547)
+++ dirsvc.c (working copy)
@@ -665,10 +665,10 @@

• Announce the deletion...
  */

• if (BrowseLocalProtocols & BROWSE_CUPS)

• if ((BrowseLocalProtocols & BROWSE_CUPS) && BrowseSocket >= 0)
  send_cups_browse(p);
  #ifdef HAVE_LIBSLP

• if (BrowseLocalProtocols & BROWSE_SLP)

• if ((BrowseLocalProtocols & BROWSE_SLP) && BrowseSLPHandle)
  slp_dereg_printer(p);
  #endif /* HAVE_LIBSLP */
  }
  @@ -934,6 +934,8 @@

  BrowseSLPRefresh = 0;
  }

• else

• BrowseSLPHandle = NULL;
  #endif /* HAVE_LIBSLP */

#ifdef HAVE_OPENLDAP