897b515f77d145b4001532cb67e0e4d8c10ae00a
[jelmer/samba4-debian.git] / source / 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 3 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, see <http://www.gnu.org/licenses/>.
20 */
21
22 #include "includes.h"
23 #include "librpc/gen_ndr/winsrepl.h"
24 #include "wrepl_server/wrepl_server.h"
25 #include "libcli/composite/composite.h"
26 #include "nbt_server/wins/winsdb.h"
27
28 static void wreplsrv_out_partner_push(struct wreplsrv_partner *partner, BOOL propagate);
29
30 static void wreplsrv_push_handler_creq(struct composite_context *creq)
31 {
32         struct wreplsrv_partner *partner = talloc_get_type(creq->async.private_data, struct wreplsrv_partner);
33         struct wreplsrv_push_notify_io *old_notify_io;
34
35         partner->push.last_status = wreplsrv_push_notify_recv(partner->push.creq);
36         partner->push.creq = NULL;
37
38         old_notify_io = partner->push.notify_io;
39         partner->push.notify_io = NULL;
40
41         if (NT_STATUS_IS_OK(partner->push.last_status)) {
42                 partner->push.error_count = 0;
43                 DEBUG(2,("wreplsrv_push_notify(%s): %s\n",
44                          partner->address, nt_errstr(partner->push.last_status)));
45                 goto done;
46         }
47
48         partner->push.error_count++;
49
50         if (partner->push.error_count > 1) {
51                 DEBUG(1,("wreplsrv_push_notify(%s): %s: error_count: %u: giving up\n",
52                          partner->address, nt_errstr(partner->push.last_status),
53                          partner->push.error_count));
54                 goto done;
55         }
56
57         DEBUG(1,("wreplsrv_push_notify(%s): %s: error_count: %u: retry\n",
58                  partner->address, nt_errstr(partner->push.last_status),
59                  partner->push.error_count));
60         wreplsrv_out_partner_push(partner, old_notify_io->in.propagate);
61 done:
62         talloc_free(old_notify_io);
63 }
64
65 static void wreplsrv_out_partner_push(struct wreplsrv_partner *partner, BOOL propagate)
66 {
67         /* a push for this partner is currently in progress, so we're done */
68         if (partner->push.creq) return;
69
70         /* now prepare the push notify */
71         partner->push.notify_io = talloc(partner, struct wreplsrv_push_notify_io);
72         if (!partner->push.notify_io) {
73                 goto nomem;
74         }
75
76         partner->push.notify_io->in.partner     = partner;
77         partner->push.notify_io->in.inform      = partner->push.use_inform;
78         partner->push.notify_io->in.propagate   = propagate;
79         partner->push.creq = wreplsrv_push_notify_send(partner->push.notify_io, partner->push.notify_io);
80         if (!partner->push.creq) {
81                 DEBUG(1,("wreplsrv_push_notify_send(%s) failed nomem?\n",
82                          partner->address));
83                 goto nomem;
84         }
85
86         partner->push.creq->async.fn            = wreplsrv_push_handler_creq;
87         partner->push.creq->async.private_data  = partner;
88
89         return;
90 nomem:
91         talloc_free(partner->push.notify_io);
92         partner->push.notify_io = NULL;
93         DEBUG(1,("wreplsrv_out_partner_push(%s,%u) failed nomem? (ignoring)\n",
94                  partner->address, propagate));
95         return;
96 }
97
98 static uint32_t wreplsrv_calc_change_count(struct wreplsrv_partner *partner, uint64_t maxVersionID)
99 {
100         uint64_t tmp_diff = UINT32_MAX;
101
102         /* catch an overflow */
103         if (partner->push.maxVersionID > maxVersionID) {
104                 goto done;
105         }
106
107         tmp_diff = maxVersionID - partner->push.maxVersionID;
108
109         if (tmp_diff > UINT32_MAX) {
110                 tmp_diff = UINT32_MAX;
111                 goto done;
112         }
113
114 done:
115         partner->push.maxVersionID = maxVersionID;
116         return (uint32_t)(tmp_diff & UINT32_MAX);
117 }
118
119 NTSTATUS wreplsrv_out_push_run(struct wreplsrv_service *service)
120 {
121         struct wreplsrv_partner *partner;
122         uint64_t seqnumber;
123         uint32_t change_count;
124
125         seqnumber = winsdb_get_maxVersion(service->wins_db);
126
127         for (partner = service->partners; partner; partner = partner->next) {
128                 /* if it's not a push partner, go to the next partner */
129                 if (!(partner->type & WINSREPL_PARTNER_PUSH)) continue;
130
131                 /* if push notifies are disabled for this partner, go to the next partner */
132                 if (partner->push.change_count == 0) continue;
133
134                 /* get the actual change count for the partner */
135                 change_count = wreplsrv_calc_change_count(partner, seqnumber);
136
137                 /* if the configured change count isn't reached, go to the next partner */
138                 if (change_count < partner->push.change_count) continue;
139
140                 wreplsrv_out_partner_push(partner, False);
141         }
142
143         return NT_STATUS_OK;
144 }