]> git.ipfire.org Git - thirdparty/cups.git/commitdiff
More Avahi changes to make cupsd resiliant to Avahi failures (STR #4373)
authormsweet <msweet@a1ca3aef-8c08-0410-bb20-df032aa958be>
Wed, 5 Mar 2014 21:10:04 +0000 (21:10 +0000)
committermsweet <msweet@a1ca3aef-8c08-0410-bb20-df032aa958be>
Wed, 5 Mar 2014 21:10:04 +0000 (21:10 +0000)
git-svn-id: svn+ssh://src.apple.com/svn/cups/cups.org/trunk@11687 a1ca3aef-8c08-0410-bb20-df032aa958be

CHANGES-1.7.txt
scheduler/dirsvc.c

index df9d3c88620c4dbb963a9f8fad7ac92874d3f2a0..7ef0ef95f2ad6e07f362a9977dae0cc4dbc6fa61 100644 (file)
@@ -20,7 +20,7 @@ CHANGES IN CUPS V1.7.2
        - Fixed a D-BUS threading issue that caused the scheduler to crash
          (STR #4347)
        - The scheduler now automatically reconnects to Avahi as needed
-         (STR #4370)
+         (STR #4370, STR #4373)
        - The scheduler did not handle GET requests for the log files properly
          (STR #3265)
        - The dnssd backend did not always report all discovered printers using
index 3f053f67f29a77c4488bfd08c4867f48343e7a0e..495bf1b7f51f9e8f32d6befb2577f330518d01ad 100644 (file)
 #endif /* HAVE_DNSSD && __APPLE__ */
 
 
+/*
+ * Local globals...
+ */
+
+#ifdef HAVE_AVAHI
+static int     avahi_running = 0;
+#endif /* HAVE_AVAHI */
+
+
 /*
  * Local functions...
  */
@@ -48,11 +57,15 @@ static void         dnssdAddAlias(const void *key, const void *value,
                                      void *context);
 #  endif /* __APPLE__ */
 static cupsd_txt_t     dnssdBuildTxtRecord(cupsd_printer_t *p, int for_lpd);
-static void            dnssdDeregisterInstance(cupsd_srv_t *srv);
-static void            dnssdDeregisterPrinter(cupsd_printer_t *p,
-                                              int clear_name);
+#  ifdef HAVE_AVAHI
+static void            dnssdClientCallback(AvahiClient *c, AvahiClientState state, void *userdata);
+#  endif /* HAVE_AVAHI */
+static void            dnssdDeregisterAllPrinters(int from_callback);
+static void            dnssdDeregisterInstance(cupsd_srv_t *srv, int from_callback);
+static void            dnssdDeregisterPrinter(cupsd_printer_t *p, int clear_name, int from_callback);
 static const char      *dnssdErrorString(int error);
 static void            dnssdFreeTxtRecord(cupsd_txt_t *txt);
+static void            dnssdRegisterAllPrinters(int from_callback);
 #  ifdef HAVE_DNSSD
 static void            dnssdRegisterCallback(DNSServiceRef sdRef,
                                              DNSServiceFlags flags,
@@ -66,16 +79,13 @@ static void         dnssdRegisterCallback(AvahiEntryGroup *p,
                                              AvahiEntryGroupState state,
                                              void *context);
 #  endif /* HAVE_DNSSD */
-static int             dnssdRegisterInstance(cupsd_srv_t *srv,
-                                             cupsd_printer_t *p,
-                                             char *name, const char *type,
-                                             const char *subtypes, int port,
-                                             cupsd_txt_t *txt, int commit);
-static void            dnssdRegisterPrinter(cupsd_printer_t *p);
+static int             dnssdRegisterInstance(cupsd_srv_t *srv, cupsd_printer_t *p, char *name, const char *type, const char *subtypes, int port, cupsd_txt_t *txt, int commit, int from_callback);
+static void            dnssdRegisterPrinter(cupsd_printer_t *p, int from_callback);
 static void            dnssdStop(void);
 #  ifdef HAVE_DNSSD
 static void            dnssdUpdate(void);
 #  endif /* HAVE_DNSSD */
+static void            dnssdUpdateDNSSDName(int from_callback);
 #endif /* HAVE_DNSSD || HAVE_AVAHI */
 
 
@@ -108,7 +118,7 @@ cupsdDeregisterPrinter(
 
 #if defined(HAVE_DNSSD) || defined(HAVE_AVAHI)
   if (removeit && (BrowseLocalProtocols & BROWSE_DNSSD) && DNSSDMaster)
-    dnssdDeregisterPrinter(p, 1);
+    dnssdDeregisterPrinter(p, 1, 0);
 #endif /* HAVE_DNSSD || HAVE_AVAHI */
 }
 
@@ -130,7 +140,7 @@ cupsdRegisterPrinter(cupsd_printer_t *p)/* I - Printer */
 
 #if defined(HAVE_DNSSD) || defined(HAVE_AVAHI)
   if ((BrowseLocalProtocols & BROWSE_DNSSD) && DNSSDMaster)
-    dnssdRegisterPrinter(p);
+    dnssdRegisterPrinter(p, 0);
 #endif /* HAVE_DNSSD || HAVE_AVAHI */
 }
 
@@ -142,16 +152,12 @@ cupsdRegisterPrinter(cupsd_printer_t *p)/* I - Printer */
 void
 cupsdStartBrowsing(void)
 {
-  cupsd_printer_t      *p;             /* Current printer */
-
-
   if (!Browsing || !BrowseLocalProtocols)
     return;
 
 #if defined(HAVE_DNSSD) || defined(HAVE_AVAHI)
   if (BrowseLocalProtocols & BROWSE_DNSSD)
   {
-    cupsd_listener_t   *lis;           /* Current listening socket */
 #  ifdef HAVE_DNSSD
     DNSServiceErrorType error;         /* Error from service creation */
 
@@ -181,6 +187,13 @@ cupsdStartBrowsing(void)
       cupsdAddSelect(fd, (cupsd_selfunc_t)dnssdUpdate, NULL, NULL);
     }
 
+   /*
+    * Set the computer name and register the web interface...
+    */
+
+    DNSSDPort = 0;
+    cupsdUpdateDNSSDName();
+
 #  else /* HAVE_AVAHI */
     if ((DNSSDMaster = avahi_threaded_poll_new()) == NULL)
     {
@@ -193,7 +206,7 @@ cupsdStartBrowsing(void)
     {
       int error;                       /* Error code, if any */
 
-      DNSSDClient = avahi_client_new(avahi_threaded_poll_get(DNSSDMaster), AVAHI_CLIENT_NO_FAIL, NULL, NULL, &error);
+      DNSSDClient = avahi_client_new(avahi_threaded_poll_get(DNSSDMaster), AVAHI_CLIENT_NO_FAIL, dnssdClientCallback, NULL, &error);
 
       if (DNSSDClient == NULL)
       {
@@ -211,31 +224,6 @@ cupsdStartBrowsing(void)
        avahi_threaded_poll_start(DNSSDMaster);
     }
 #  endif /* HAVE_DNSSD */
-
-   /*
-    * Then get the port we use for registrations.  If we are not listening
-    * on any non-local ports, there is no sense sharing local printers via
-    * Bonjour...
-    */
-
-    DNSSDPort = 0;
-
-    for (lis = (cupsd_listener_t *)cupsArrayFirst(Listeners);
-        lis;
-        lis = (cupsd_listener_t *)cupsArrayNext(Listeners))
-    {
-      if (httpAddrLocalhost(&(lis->address)))
-       continue;
-
-      DNSSDPort = httpAddrPort(&(lis->address));
-      break;
-    }
-
-   /*
-    * Set the computer name and register the web interface...
-    */
-
-    cupsdUpdateDNSSDName();
   }
 #endif /* HAVE_DNSSD || HAVE_AVAHI */
 
@@ -253,11 +241,7 @@ cupsdStartBrowsing(void)
   * Register the individual printers
   */
 
-  for (p = (cupsd_printer_t *)cupsArrayFirst(Printers);
-       p;
-       p = (cupsd_printer_t *)cupsArrayNext(Printers))
-    if (!(p->type & (CUPS_PRINTER_REMOTE | CUPS_PRINTER_SCANNER)))
-      cupsdRegisterPrinter(p);
+  dnssdRegisterAllPrinters(0);
 }
 
 
@@ -268,9 +252,6 @@ cupsdStartBrowsing(void)
 void
 cupsdStopBrowsing(void)
 {
-  cupsd_printer_t      *p;             /* Current printer */
-
-
   if (!Browsing || !BrowseLocalProtocols)
     return;
 
@@ -278,11 +259,7 @@ cupsdStopBrowsing(void)
   * De-register the individual printers
   */
 
-  for (p = (cupsd_printer_t *)cupsArrayFirst(Printers);
-       p;
-       p = (cupsd_printer_t *)cupsArrayNext(Printers))
-    if (!(p->type & (CUPS_PRINTER_REMOTE | CUPS_PRINTER_SCANNER)))
-      cupsdDeregisterPrinter(p, 1);
+  dnssdDeregisterAllPrinters(0);
 
  /*
   * Shut down browsing sockets...
@@ -313,161 +290,7 @@ cupsdStopBrowsing(void)
 void
 cupsdUpdateDNSSDName(void)
 {
-  char         webif[1024];            /* Web interface share name */
-#  ifdef __APPLE__
-  SCDynamicStoreRef sc;                        /* Context for dynamic store */
-  CFDictionaryRef btmm;                        /* Back-to-My-Mac domains */
-  CFStringEncoding nameEncoding;       /* Encoding of computer name */
-  CFStringRef  nameRef;                /* Host name CFString */
-  char         nameBuffer[1024];       /* C-string buffer */
-#  endif /* __APPLE__ */
-
-
- /*
-  * Only share the web interface and printers when non-local listening is
-  * enabled...
-  */
-
-  if (!DNSSDPort)
-    return;
-
- /*
-  * Get the computer name as a c-string...
-  */
-
-#  ifdef __APPLE__
-  sc = SCDynamicStoreCreate(kCFAllocatorDefault, CFSTR("cupsd"), NULL, NULL);
-
-  if (sc)
-  {
-   /*
-    * Get the computer name from the dynamic store...
-    */
-
-    cupsdClearString(&DNSSDComputerName);
-
-    if ((nameRef = SCDynamicStoreCopyComputerName(sc, &nameEncoding)) != NULL)
-    {
-      if (CFStringGetCString(nameRef, nameBuffer, sizeof(nameBuffer),
-                            kCFStringEncodingUTF8))
-      {
-        cupsdLogMessage(CUPSD_LOG_DEBUG,
-                       "Dynamic store computer name is \"%s\".", nameBuffer);
-       cupsdSetString(&DNSSDComputerName, nameBuffer);
-      }
-
-      CFRelease(nameRef);
-    }
-
-    if (!DNSSDComputerName)
-    {
-     /*
-      * Use the ServerName instead...
-      */
-
-      cupsdLogMessage(CUPSD_LOG_DEBUG,
-                      "Using ServerName \"%s\" as computer name.", ServerName);
-      cupsdSetString(&DNSSDComputerName, ServerName);
-    }
-
-   /*
-    * Get the local hostname from the dynamic store...
-    */
-
-    cupsdClearString(&DNSSDHostName);
-
-    if ((nameRef = SCDynamicStoreCopyLocalHostName(sc)) != NULL)
-    {
-      if (CFStringGetCString(nameRef, nameBuffer, sizeof(nameBuffer),
-                            kCFStringEncodingUTF8))
-      {
-        cupsdLogMessage(CUPSD_LOG_DEBUG,
-                       "Dynamic store host name is \"%s\".", nameBuffer);
-       cupsdSetString(&DNSSDHostName, nameBuffer);
-      }
-
-      CFRelease(nameRef);
-    }
-
-    if (!DNSSDHostName)
-    {
-     /*
-      * Use the ServerName instead...
-      */
-
-      cupsdLogMessage(CUPSD_LOG_DEBUG,
-                      "Using ServerName \"%s\" as host name.", ServerName);
-      cupsdSetString(&DNSSDHostName, ServerName);
-    }
-
-   /*
-    * Get any Back-to-My-Mac domains and add them as aliases...
-    */
-
-    cupsdFreeAliases(DNSSDAlias);
-    DNSSDAlias = NULL;
-
-    btmm = SCDynamicStoreCopyValue(sc, CFSTR("Setup:/Network/BackToMyMac"));
-    if (btmm && CFGetTypeID(btmm) == CFDictionaryGetTypeID())
-    {
-      cupsdLogMessage(CUPSD_LOG_DEBUG, "%d Back to My Mac aliases to add.",
-                     (int)CFDictionaryGetCount(btmm));
-      CFDictionaryApplyFunction(btmm, dnssdAddAlias, NULL);
-    }
-    else if (btmm)
-      cupsdLogMessage(CUPSD_LOG_ERROR,
-                     "Bad Back to My Mac data in dynamic store!");
-    else
-      cupsdLogMessage(CUPSD_LOG_DEBUG, "No Back to My Mac aliases to add.");
-
-    if (btmm)
-      CFRelease(btmm);
-
-    CFRelease(sc);
-  }
-  else
-#  endif /* __APPLE__ */
-#  ifdef HAVE_AVAHI
-  if (DNSSDClient)
-  {
-    const char *host_name = avahi_client_get_host_name(DNSSDClient);
-    const char *host_fqdn = avahi_client_get_host_name_fqdn(DNSSDClient);
-
-    cupsdSetString(&DNSSDComputerName, host_name ? host_name : ServerName);
-
-    if (host_fqdn)
-      cupsdSetString(&DNSSDHostName, host_fqdn);
-    else if (strchr(ServerName, '.'))
-      cupsdSetString(&DNSSDHostName, ServerName);
-    else
-      cupsdSetStringf(&DNSSDHostName, "%s.local", ServerName);
-  }
-  else
-#  endif /* HAVE_AVAHI */
-  {
-    cupsdSetString(&DNSSDComputerName, ServerName);
-
-    if (strchr(ServerName, '.'))
-      cupsdSetString(&DNSSDHostName, ServerName);
-    else
-      cupsdSetStringf(&DNSSDHostName, "%s.local", ServerName);
-  }
-
- /*
-  * Then (re)register the web interface if enabled...
-  */
-
-  if (BrowseWebIF)
-  {
-    if (DNSSDComputerName)
-      snprintf(webif, sizeof(webif), "CUPS @ %s", DNSSDComputerName);
-    else
-      strlcpy(webif, "CUPS", sizeof(webif));
-
-    dnssdDeregisterInstance(&WebIFSrv);
-    dnssdRegisterInstance(&WebIFSrv, NULL, webif, "_http._tcp", "_printer",
-                          DNSSDPort, NULL, 1);
-  }
+  dnssdUpdateDNSSDName(0);
 }
 
 
@@ -702,24 +525,158 @@ dnssdBuildTxtRecord(
 }
 
 
+#  ifdef HAVE_AVAHI
+/*
+ * 'dnssdClientCallback()' - Client callback for Avahi.
+ *
+ * Called whenever the client or server state changes...
+ */
+
+static void
+dnssdClientCallback(
+    AvahiClient      *c,               /* I - Client */
+    AvahiClientState state,            /* I - Current state */
+    void             *userdata)                /* I - User data (unused) */
+{
+  int  error;                          /* Error code, if any */
+
+
+  (void)userdata;
+
+  if (!c)
+    return;
+
+ /*
+  * Make sure DNSSDClient is already set also if this callback function is
+  * already running before avahi_client_new() in dnssdStartBrowsing()
+  * finishes.
+  */
+
+  if (!DNSSDClient)
+    DNSSDClient = c;
+
+  switch (state)
+  {
+    case AVAHI_CLIENT_S_REGISTERING:
+    case AVAHI_CLIENT_S_RUNNING:
+    case AVAHI_CLIENT_S_COLLISION:
+       cupsdLogMessage(CUPSD_LOG_DEBUG, "Avahi server connection now available, registering printers for Bonjour broadcasting.");
+
+       /*
+       * Mark that Avahi server is running...
+       */
+
+       avahi_running = 1;
+
+       /*
+       * Set the computer name and register the web interface...
+       */
+
+       DNSSDPort = 0;
+       dnssdUpdateDNSSDName(1);
+
+       /*
+       * Register the individual printers
+       */
+
+       dnssdRegisterAllPrinters(1);
+       break;
+
+    case AVAHI_CLIENT_FAILURE:
+       if (avahi_client_errno(c) == AVAHI_ERR_DISCONNECTED)
+       {
+         cupsdLogMessage(CUPSD_LOG_DEBUG, "Avahi server disappeared, unregistering printers for Bonjour broadcasting.");
+
+        /*
+         * Unregister everything and close the client...
+         */
+
+         dnssdDeregisterAllPrinters(1);
+         dnssdDeregisterInstance(&WebIFSrv, 1);
+         avahi_client_free(DNSSDClient);
+         DNSSDClient = NULL;
+
+        /*
+         * Mark that Avahi server is not running...
+         */
+
+         avahi_running = 0;
+
+        /*
+         * Renew Avahi client...
+         */
+
+         DNSSDClient = avahi_client_new(avahi_threaded_poll_get(DNSSDMaster), AVAHI_CLIENT_NO_FAIL, dnssdClientCallback, NULL, &error);
+
+         if (!DNSSDClient)
+         {
+           cupsdLogMessage(CUPSD_LOG_ERROR, "Unable to communicate with avahi-daemon: %s", dnssdErrorString(error));
+           if (FatalErrors & CUPSD_FATAL_BROWSE)
+             cupsdEndProcess(getpid(), 0);
+         }
+       }
+       else
+       {
+         cupsdLogMessage(CUPSD_LOG_ERROR, "Communication with avahi-daemon has failed: %s", avahi_strerror(avahi_client_errno(c)));
+         if (FatalErrors & CUPSD_FATAL_BROWSE)
+           cupsdEndProcess(getpid(), 0);
+       }
+       break;
+
+    default:
+        break;
+  }
+}
+#  endif /* HAVE_AVAHI */
+
+
+/*
+ * 'dnssdDeregisterAllPrinters()' - Deregister all printers.
+ */
+
+static void
+dnssdDeregisterAllPrinters(
+    int             from_callback)     /* I - Deregistering because of callback? */
+{
+  cupsd_printer_t      *p;             /* Current printer */
+
+
+  if (!DNSSDMaster)
+    return;
+
+  for (p = (cupsd_printer_t *)cupsArrayFirst(Printers);
+       p;
+       p = (cupsd_printer_t *)cupsArrayNext(Printers))
+    if (!(p->type & (CUPS_PRINTER_REMOTE | CUPS_PRINTER_SCANNER)))
+      dnssdDeregisterPrinter(p, 1, from_callback);
+}
+
+
 /*
  * 'dnssdDeregisterInstance()' - Deregister a DNS-SD service instance.
  */
 
 static void
 dnssdDeregisterInstance(
-    cupsd_srv_t     *srv)              /* I - Service */
+    cupsd_srv_t     *srv,              /* I - Service */
+    int             from_callback)     /* I - Called from callback? */
 {
   if (!srv || !*srv)
     return;
 
 #  ifdef HAVE_DNSSD
+  (void)from_callback;
+
   DNSServiceRefDeallocate(*srv);
 
 #  else /* HAVE_AVAHI */
-  avahi_threaded_poll_lock(DNSSDMaster);
+  if (!from_callback)
+    avahi_threaded_poll_lock(DNSSDMaster);
+
   avahi_entry_group_free(*srv);
-  avahi_threaded_poll_unlock(DNSSDMaster);
+
+  if (!from_callback)
+    avahi_threaded_poll_unlock(DNSSDMaster);
 #  endif /* HAVE_DNSSD */
 
   *srv = NULL;
@@ -733,7 +690,8 @@ dnssdDeregisterInstance(
 static void
 dnssdDeregisterPrinter(
     cupsd_printer_t *p,                        /* I - Printer */
-    int             clear_name)                /* I - Clear the name? */
+    int             clear_name,                /* I - Clear the name? */
+    int             from_callback)     /* I - Called from callback? */
 
 {
   cupsdLogMessage(CUPSD_LOG_DEBUG2,
@@ -742,13 +700,13 @@ dnssdDeregisterPrinter(
 
   if (p->ipp_srv)
   {
-    dnssdDeregisterInstance(&p->ipp_srv);
+    dnssdDeregisterInstance(&p->ipp_srv, from_callback);
 
 #  ifdef HAVE_DNSSD
 #    ifdef HAVE_SSL
-    dnssdDeregisterInstance(&p->ipps_srv);
+    dnssdDeregisterInstance(&p->ipps_srv, from_callback);
 #    endif /* HAVE_SSL */
-    dnssdDeregisterInstance(&p->printer_srv);
+    dnssdDeregisterInstance(&p->printer_srv, from_callback);
 #  endif /* HAVE_DNSSD */
   }
 
@@ -899,6 +857,27 @@ dnssdFreeTxtRecord(cupsd_txt_t *txt)       /* I - TXT record */
 }
 
 
+/*
+ * 'dnssdRegisterAllPrinters()' - Register all printers.
+ */
+
+static void
+dnssdRegisterAllPrinters(int from_callback)    /* I - Called from callback? */
+{
+  cupsd_printer_t      *p;                     /* Current printer */
+
+
+  if (!DNSSDMaster)
+    return;
+
+  for (p = (cupsd_printer_t *)cupsArrayFirst(Printers);
+       p;
+       p = (cupsd_printer_t *)cupsArrayNext(Printers))
+    if (!(p->type & (CUPS_PRINTER_REMOTE | CUPS_PRINTER_SCANNER)))
+      dnssdRegisterPrinter(p, from_callback);
+}
+
+
 /*
  * 'dnssdRegisterCallback()' - DNSServiceRegister callback.
  */
@@ -979,15 +958,19 @@ dnssdRegisterInstance(
     const char      *subtypes,         /* I - Subtypes to register or NULL */
     int             port,              /* I - Port number or 0 */
     cupsd_txt_t     *txt,              /* I - TXT record */
-    int             commit)            /* I - Commit registration? */
+    int             commit,            /* I - Commit registration? */
+    int             from_callback)     /* I - Called from callback? */
 {
   char temp[256],                      /* Temporary string */
        *ptr;                           /* Pointer into string */
   int  error;                          /* Any error */
 
 
-  cupsdLogMessage(CUPSD_LOG_DEBUG,
-                 "Registering \"%s\" with DNS-SD type \"%s\".", name, type);
+#  ifdef HAVE_DNSSD
+  (void)from_callback;
+#  endif /* HAVE_DNSSD */
+
+  cupsdLogMessage(CUPSD_LOG_DEBUG, "Registering \"%s\" with DNS-SD type \"%s\".", name, type);
 
   if (p && !srv)
   {
@@ -1014,13 +997,15 @@ dnssdRegisterInstance(
   (void)commit;
 
 #  else /* HAVE_AVAHI */
-  avahi_threaded_poll_lock(DNSSDMaster);
+  if (!from_callback)
+    avahi_threaded_poll_lock(DNSSDMaster);
 
   if (!*srv)
     *srv = avahi_entry_group_new(DNSSDClient, dnssdRegisterCallback, NULL);
   if (!*srv)
   {
-    avahi_threaded_poll_unlock(DNSSDMaster);
+    if (!from_callback)
+      avahi_threaded_poll_unlock(DNSSDMaster);
 
     cupsdLogMessage(CUPSD_LOG_WARN, "DNS-SD registration of \"%s\" failed: %s",
                     name, dnssdErrorString(avahi_client_errno(DNSSDClient)));
@@ -1137,7 +1122,8 @@ dnssdRegisterInstance(
                       name);
   }
 
-  avahi_threaded_poll_unlock(DNSSDMaster);
+  if (!from_callback)
+    avahi_threaded_poll_unlock(DNSSDMaster);
 #  endif /* HAVE_DNSSD */
 
   if (error)
@@ -1159,7 +1145,9 @@ dnssdRegisterInstance(
  */
 
 static void
-dnssdRegisterPrinter(cupsd_printer_t *p)/* I - Printer */
+dnssdRegisterPrinter(
+    cupsd_printer_t *p,                        /* I - Printer */
+    int             from_callback)     /* I - Called from callback? */
 {
   char         name[256];              /* Service name */
   int          printer_port;           /* LPD port number */
@@ -1167,15 +1155,21 @@ dnssdRegisterPrinter(cupsd_printer_t *p)/* I - Printer */
   cupsd_txt_t  ipp_txt,                /* IPP(S) TXT record */
                printer_txt;            /* LPD TXT record */
 
+
   cupsdLogMessage(CUPSD_LOG_DEBUG2, "dnssdRegisterPrinter(%s) %s", p->name,
                   !p->ipp_srv ? "new" : "update");
 
+#  ifdef HAVE_AVAHI
+  if (!avahi_running)
+    return;
+#  endif /* HAVE_AVAHI */
+
  /*
   * Remove the current registrations if we have them and then return if
   * per-printer sharing was just disabled...
   */
 
-  dnssdDeregisterPrinter(p, 0);
+  dnssdDeregisterPrinter(p, 0, from_callback);
 
   if (!p->shared)
     return;
@@ -1218,13 +1212,11 @@ dnssdRegisterPrinter(cupsd_printer_t *p)/* I - Printer */
   else
     printer_port = 0;
 
-  status = dnssdRegisterInstance(NULL, p, name, "_printer._tcp", NULL,
-                                 printer_port, &printer_txt, 0);
+  status = dnssdRegisterInstance(NULL, p, name, "_printer._tcp", NULL, printer_port, &printer_txt, 0, from_callback);
 
 #  ifdef HAVE_SSL
   if (status)
-    dnssdRegisterInstance(NULL, p, name, "_ipps._tcp", DNSSDSubTypes,
-                         DNSSDPort, &ipp_txt, 0);
+    dnssdRegisterInstance(NULL, p, name, "_ipps._tcp", DNSSDSubTypes, DNSSDPort, &ipp_txt, 0, from_callback);
 #  endif /* HAVE_SSL */
 
   if (status)
@@ -1234,11 +1226,9 @@ dnssdRegisterPrinter(cupsd_printer_t *p)/* I - Printer */
     */
 
     if (p->type & CUPS_PRINTER_FAX)
-      status = dnssdRegisterInstance(NULL, p, name, "_fax-ipp._tcp",
-                                     DNSSDSubTypes, DNSSDPort, &ipp_txt, 1);
+      status = dnssdRegisterInstance(NULL, p, name, "_fax-ipp._tcp", DNSSDSubTypes, DNSSDPort, &ipp_txt, 1, from_callback);
     else
-      status = dnssdRegisterInstance(NULL, p, name, "_ipp._tcp", DNSSDSubTypes,
-                                     DNSSDPort, &ipp_txt, 1);
+      status = dnssdRegisterInstance(NULL, p, name, "_ipp._tcp", DNSSDSubTypes, DNSSDPort, &ipp_txt, 1, from_callback);
   }
 
   dnssdFreeTxtRecord(&ipp_txt);
@@ -1260,13 +1250,13 @@ dnssdRegisterPrinter(cupsd_printer_t *p)/* I - Printer */
     * Registration failed for this printer...
     */
 
-    dnssdDeregisterInstance(&p->ipp_srv);
+    dnssdDeregisterInstance(&p->ipp_srv, from_callback);
 
 #  ifdef HAVE_DNSSD
 #    ifdef HAVE_SSL
-    dnssdDeregisterInstance(&p->ipps_srv);
+    dnssdDeregisterInstance(&p->ipps_srv, from_callback);
 #    endif /* HAVE_SSL */
-    dnssdDeregisterInstance(&p->printer_srv);
+    dnssdDeregisterInstance(&p->printer_srv, from_callback);
 #  endif /* HAVE_DNSSD */
   }
 }
@@ -1289,13 +1279,13 @@ dnssdStop(void)
   for (p = (cupsd_printer_t *)cupsArrayFirst(Printers);
        p;
        p = (cupsd_printer_t *)cupsArrayNext(Printers))
-    dnssdDeregisterPrinter(p, 1);
+    dnssdDeregisterPrinter(p, 1, 0);
 
  /*
   * Shutdown the rest of the service refs...
   */
 
-  dnssdDeregisterInstance(&WebIFSrv);
+  dnssdDeregisterInstance(&WebIFSrv, 0);
 
 #  ifdef HAVE_DNSSD
   cupsdRemoveSelect(DNSServiceRefSockFD(DNSSDMaster));
@@ -1342,6 +1332,191 @@ dnssdUpdate(void)
 #  endif /* HAVE_DNSSD */
 
 
+/*
+ * 'dnssdUpdateDNSSDName()' - Update the listen port, computer name, and web interface registration.
+ */
+
+static void
+dnssdUpdateDNSSDName(int from_callback)        /* I - Called from callback? */
+{
+  char         webif[1024];            /* Web interface share name */
+#  ifdef __APPLE__
+  SCDynamicStoreRef sc;                        /* Context for dynamic store */
+  CFDictionaryRef btmm;                        /* Back-to-My-Mac domains */
+  CFStringEncoding nameEncoding;       /* Encoding of computer name */
+  CFStringRef  nameRef;                /* Host name CFString */
+  char         nameBuffer[1024];       /* C-string buffer */
+#  endif /* __APPLE__ */
+
+
+ /*
+  * Only share the web interface and printers when non-local listening is
+  * enabled...
+  */
+
+  if (!DNSSDPort)
+  {
+   /*
+    * Get the port we use for registrations.  If we are not listening on any
+    * non-local ports, there is no sense sharing local printers via Bonjour...
+    */
+
+    cupsd_listener_t   *lis;           /* Current listening socket */
+
+    for (lis = (cupsd_listener_t *)cupsArrayFirst(Listeners);
+        lis;
+        lis = (cupsd_listener_t *)cupsArrayNext(Listeners))
+    {
+      if (httpAddrLocalhost(&(lis->address)))
+       continue;
+
+      DNSSDPort = httpAddrPort(&(lis->address));
+      break;
+    }
+  }
+
+  if (!DNSSDPort)
+    return;
+
+ /*
+  * Get the computer name as a c-string...
+  */
+
+#  ifdef __APPLE__
+  sc = SCDynamicStoreCreate(kCFAllocatorDefault, CFSTR("cupsd"), NULL, NULL);
+
+  if (sc)
+  {
+   /*
+    * Get the computer name from the dynamic store...
+    */
+
+    cupsdClearString(&DNSSDComputerName);
+
+    if ((nameRef = SCDynamicStoreCopyComputerName(sc, &nameEncoding)) != NULL)
+    {
+      if (CFStringGetCString(nameRef, nameBuffer, sizeof(nameBuffer),
+                            kCFStringEncodingUTF8))
+      {
+        cupsdLogMessage(CUPSD_LOG_DEBUG,
+                       "Dynamic store computer name is \"%s\".", nameBuffer);
+       cupsdSetString(&DNSSDComputerName, nameBuffer);
+      }
+
+      CFRelease(nameRef);
+    }
+
+    if (!DNSSDComputerName)
+    {
+     /*
+      * Use the ServerName instead...
+      */
+
+      cupsdLogMessage(CUPSD_LOG_DEBUG,
+                      "Using ServerName \"%s\" as computer name.", ServerName);
+      cupsdSetString(&DNSSDComputerName, ServerName);
+    }
+
+   /*
+    * Get the local hostname from the dynamic store...
+    */
+
+    cupsdClearString(&DNSSDHostName);
+
+    if ((nameRef = SCDynamicStoreCopyLocalHostName(sc)) != NULL)
+    {
+      if (CFStringGetCString(nameRef, nameBuffer, sizeof(nameBuffer),
+                            kCFStringEncodingUTF8))
+      {
+        cupsdLogMessage(CUPSD_LOG_DEBUG,
+                       "Dynamic store host name is \"%s\".", nameBuffer);
+       cupsdSetString(&DNSSDHostName, nameBuffer);
+      }
+
+      CFRelease(nameRef);
+    }
+
+    if (!DNSSDHostName)
+    {
+     /*
+      * Use the ServerName instead...
+      */
+
+      cupsdLogMessage(CUPSD_LOG_DEBUG,
+                      "Using ServerName \"%s\" as host name.", ServerName);
+      cupsdSetString(&DNSSDHostName, ServerName);
+    }
+
+   /*
+    * Get any Back-to-My-Mac domains and add them as aliases...
+    */
+
+    cupsdFreeAliases(DNSSDAlias);
+    DNSSDAlias = NULL;
+
+    btmm = SCDynamicStoreCopyValue(sc, CFSTR("Setup:/Network/BackToMyMac"));
+    if (btmm && CFGetTypeID(btmm) == CFDictionaryGetTypeID())
+    {
+      cupsdLogMessage(CUPSD_LOG_DEBUG, "%d Back to My Mac aliases to add.",
+                     (int)CFDictionaryGetCount(btmm));
+      CFDictionaryApplyFunction(btmm, dnssdAddAlias, NULL);
+    }
+    else if (btmm)
+      cupsdLogMessage(CUPSD_LOG_ERROR,
+                     "Bad Back to My Mac data in dynamic store!");
+    else
+      cupsdLogMessage(CUPSD_LOG_DEBUG, "No Back to My Mac aliases to add.");
+
+    if (btmm)
+      CFRelease(btmm);
+
+    CFRelease(sc);
+  }
+  else
+#  endif /* __APPLE__ */
+#  ifdef HAVE_AVAHI
+  if (DNSSDClient)
+  {
+    const char *host_name = avahi_client_get_host_name(DNSSDClient);
+    const char *host_fqdn = avahi_client_get_host_name_fqdn(DNSSDClient);
+
+    cupsdSetString(&DNSSDComputerName, host_name ? host_name : ServerName);
+
+    if (host_fqdn)
+      cupsdSetString(&DNSSDHostName, host_fqdn);
+    else if (strchr(ServerName, '.'))
+      cupsdSetString(&DNSSDHostName, ServerName);
+    else
+      cupsdSetStringf(&DNSSDHostName, "%s.local", ServerName);
+  }
+  else
+#  endif /* HAVE_AVAHI */
+  {
+    cupsdSetString(&DNSSDComputerName, ServerName);
+
+    if (strchr(ServerName, '.'))
+      cupsdSetString(&DNSSDHostName, ServerName);
+    else
+      cupsdSetStringf(&DNSSDHostName, "%s.local", ServerName);
+  }
+
+ /*
+  * Then (re)register the web interface if enabled...
+  */
+
+  if (BrowseWebIF)
+  {
+    if (DNSSDComputerName)
+      snprintf(webif, sizeof(webif), "CUPS @ %s", DNSSDComputerName);
+    else
+      strlcpy(webif, "CUPS", sizeof(webif));
+
+    dnssdDeregisterInstance(&WebIFSrv, from_callback);
+    dnssdRegisterInstance(&WebIFSrv, NULL, webif, "_http._tcp", "_printer", DNSSDPort, NULL, 1, from_callback);
+  }
+}
+
+
 /*
  * 'get_auth_info_required()' - Get the auth-info-required value to advertise.
  */