source4/wrepl_server/wrepl_out_push.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3
   4    WINS Replication server
   5
   6    Copyright (C) Stefan Metzmacher      2005
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    You should have received a copy of the GNU General Public License
  19    along with this program; if not, write to the Free Software
  20    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  21 */
  22
  23 #include "includes.h"
  24 #include "librpc/gen_ndr/ndr_winsrepl.h"
  25 #include "wrepl_server/wrepl_server.h"
  26 #include "libcli/composite/composite.h"
  27 #include "nbt_server/wins/winsdb.h"
  28
  29 static void wreplsrv_out_partner_push(struct wreplsrv_partner *partner, BOOL propagate);
  30
  31 static void wreplsrv_push_handler_creq(struct composite_context *creq)
  32 {
  33         struct wreplsrv_partner *partner = talloc_get_type(creq->async.private_data, struct wreplsrv_partner);
  34         struct wreplsrv_push_notify_io *old_notify_io;
  35
  36         partner->push.last_status = wreplsrv_push_notify_recv(partner->push.creq);
  37         partner->push.creq = NULL;
  38
  39         old_notify_io = partner->push.notify_io;
  40         partner->push.notify_io = NULL;
  41
  42         if (NT_STATUS_IS_OK(partner->push.last_status)) {
  43                 partner->push.error_count = 0;
  44                 DEBUG(2,("wreplsrv_push_notify(%s): %s\n",
  45                          partner->address, nt_errstr(partner->push.last_status)));
  46                 goto done;
  47         }
  48
  49         partner->push.error_count++;
  50
  51         if (partner->push.error_count > 1) {
  52                 DEBUG(1,("wreplsrv_push_notify(%s): %s: error_count: %u: giving up\n",
  53                          partner->address, nt_errstr(partner->push.last_status),
  54                          partner->push.error_count));
  55                 goto done;
  56         }
  57
  58         DEBUG(1,("wreplsrv_push_notify(%s): %s: error_count: %u: retry\n",
  59                  partner->address, nt_errstr(partner->push.last_status),
  60                  partner->push.error_count));
  61         wreplsrv_out_partner_push(partner, old_notify_io->in.propagate);
  62 done:
  63         talloc_free(old_notify_io);
  64 }
  65
  66 static void wreplsrv_out_partner_push(struct wreplsrv_partner *partner, BOOL propagate)
  67 {
  68         /* a push for this partner is currently in progress, so we're done */
  69         if (partner->push.creq) return;
  70
  71         /* now prepare the push notify */
  72         partner->push.notify_io = talloc(partner, struct wreplsrv_push_notify_io);
  73         if (!partner->push.notify_io) {
  74                 goto nomem;
  75         }
  76
  77         partner->push.notify_io->in.partner     = partner;
  78         partner->push.notify_io->in.inform      = partner->push.use_inform;
  79         partner->push.notify_io->in.propagate   = propagate;
  80         partner->push.creq = wreplsrv_push_notify_send(partner->push.notify_io, partner->push.notify_io);
  81         if (!partner->push.creq) {
  82                 DEBUG(1,("wreplsrv_push_notify_send(%s) failed nomem?\n",
  83                          partner->address));
  84                 goto nomem;
  85         }
  86
  87         partner->push.creq->async.fn            = wreplsrv_push_handler_creq;
  88         partner->push.creq->async.private_data  = partner;
  89
  90         return;
  91 nomem:
  92         talloc_free(partner->push.notify_io);
  93         partner->push.notify_io = NULL;
  94         DEBUG(1,("wreplsrv_out_partner_push(%s,%u) failed nomem? (ignoring)\n",
  95                  partner->address, propagate));
  96         return;
  97 }
  98
  99 static uint32_t wreplsrv_calc_change_count(struct wreplsrv_partner *partner, uint64_t seqnumber)
 100 {
 101         uint64_t tmp_diff = UINT32_MAX;
 102
 103         /* catch an overflow */
 104         if (partner->push.seqnumber > seqnumber) {
 105                 goto done;
 106         }
 107
 108         tmp_diff = seqnumber - partner->push.seqnumber;
 109
 110         if (tmp_diff > UINT32_MAX) {
 111                 tmp_diff = UINT32_MAX;
 112                 goto done;
 113         }
 114
 115 done:
 116         partner->push.seqnumber = seqnumber;
 117         return (uint32_t)(tmp_diff & UINT32_MAX);
 118 }
 119
 120 NTSTATUS wreplsrv_out_push_run(struct wreplsrv_service *service)
 121 {
 122         struct wreplsrv_partner *partner;
 123         uint64_t seqnumber;
 124         uint32_t change_count;
 125
 126         seqnumber = winsdb_get_seqnumber(service->wins_db);
 127
 128         for (partner = service->partners; partner; partner = partner->next) {
 129                 /* if it's not a push partner, go to the next partner */
 130                 if (!(partner->type & WINSREPL_PARTNER_PUSH)) continue;
 131
 132                 /* if push notifies are disabled for this partner, go to the next partner */
 133                 if (partner->push.change_count == 0) continue;
 134
 135                 /* get the actual change count for the partner */
 136                 change_count = wreplsrv_calc_change_count(partner, seqnumber);
 137
 138                 /* if the configured change count isn't reached, go to the next partner */
 139                 if (change_count < partner->push.change_count) continue;
 140
 141                 wreplsrv_out_partner_push(partner, False);
 142         }
 143
 144         return NT_STATUS_OK;
 145 }