1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
|
From 789325996ab38d1b8be5c2d204b536c355105844 Mon Sep 17 00:00:00 2001
From: Kaarle Ritvanen <kaarle.ritvanen@datakunkku.fi>
Date: Thu, 4 Aug 2016 12:26:56 +0200
Subject: [PATCH 13/15] ntpd: postpone hostname resolution if fails on startup
Signed-off-by: Kaarle Ritvanen <kaarle.ritvanen@datakunkku.fi>
---
networking/ntpd.c | 129 ++++++++++++++++++++++++++----------------------------
1 file changed, 63 insertions(+), 66 deletions(-)
diff --git a/networking/ntpd.c b/networking/ntpd.c
index 98158a3..7f7d69e 100644
--- a/networking/ntpd.c
+++ b/networking/ntpd.c
@@ -267,6 +267,7 @@ typedef struct {
typedef struct {
len_and_sockaddr *p_lsa;
+ char *p_hostname;
char *p_dotted;
int p_fd;
int datapoint_idx;
@@ -292,7 +293,6 @@ typedef struct {
datapoint_t filter_datapoint[NUM_DATAPOINTS];
/* last sent packet: */
msg_t p_xmt_msg;
- char p_hostname[1];
} peer_t;
@@ -765,27 +765,17 @@ reset_peer_stats(peer_t *p, double offset)
}
static void
-resolve_peer_hostname(peer_t *p, int loop_on_fail)
-{
- len_and_sockaddr *lsa;
-
- again:
- lsa = host2sockaddr(p->p_hostname, 123);
- if (!lsa) {
- /* error message already emitted by host2sockaddr() */
- if (!loop_on_fail)
- return;
-//FIXME: do this to avoid infinite looping on typo in a hostname?
-//well... in which case, what is a good value for loop_on_fail?
- //if (--loop_on_fail == 0)
- // xfunc_die();
- sleep(5);
- goto again;
+resolve_peer_hostname(peer_t *p) {
+ len_and_sockaddr *lsa = host2sockaddr(p->p_hostname, 123);
+ if (lsa) {
+ if (p->p_lsa) {
+ free(p->p_lsa);
+ free(p->p_dotted);
+ }
+ p->p_lsa = lsa;
+ p->p_dotted = xmalloc_sockaddr2dotted_noport(&lsa->u.sa);
}
- free(p->p_lsa);
- free(p->p_dotted);
- p->p_lsa = lsa;
- p->p_dotted = xmalloc_sockaddr2dotted_noport(&lsa->u.sa);
+ set_next(p, lsa ? 0 : RETRY_INTERVAL);
}
static void
@@ -794,28 +784,29 @@ add_peers(const char *s)
llist_t *item;
peer_t *p;
- p = xzalloc(sizeof(*p) + strlen(s));
- strcpy(p->p_hostname, s);
- resolve_peer_hostname(p, /*loop_on_fail=*/ 1);
+ p = xzalloc(sizeof(*p));
+ p->p_hostname = xstrdup(s);
+ resolve_peer_hostname(p);
/* Names like N.<country2chars>.pool.ntp.org are randomly resolved
* to a pool of machines. Sometimes different N's resolve to the same IP.
* It is not useful to have two peers with same IP. We skip duplicates.
*/
- for (item = G.ntp_peers; item != NULL; item = item->link) {
- peer_t *pp = (peer_t *) item->data;
- if (strcmp(p->p_dotted, pp->p_dotted) == 0) {
- bb_error_msg("duplicate peer %s (%s)", s, p->p_dotted);
- free(p->p_lsa);
- free(p->p_dotted);
- free(p);
- return;
+ if (p->p_lsa)
+ for (item = G.ntp_peers; item != NULL; item = item->link) {
+ peer_t *pp = (peer_t *) item->data;
+ if (pp->p_lsa && strcmp(p->p_dotted, pp->p_dotted) == 0) {
+ bb_error_msg("duplicate peer %s (%s)", s, p->p_dotted);
+ free(p->p_hostname);
+ free(p->p_lsa);
+ free(p->p_dotted);
+ free(p);
+ return;
+ }
}
- }
p->p_fd = -1;
p->p_xmt_msg.m_status = MODE_CLIENT | (NTP_VERSION << 3);
- p->next_action_time = G.cur_time; /* = set_next(p, 0); */
reset_peer_stats(p, STEP_THRESHOLD);
llist_add_to(&G.ntp_peers, p);
@@ -2340,44 +2331,50 @@ int ntpd_main(int argc UNUSED_PARAM, char **argv)
for (item = G.ntp_peers; item != NULL; item = item->link) {
peer_t *p = (peer_t *) item->data;
- if (p->next_action_time <= G.cur_time) {
- if (p->p_fd == -1) {
- /* Time to send new req */
- if (--cnt == 0) {
- VERB4 bb_error_msg("disabling burst mode");
- G.polladj_count = 0;
- G.poll_exp = MINPOLL;
+ if (p->p_lsa) {
+
+ if (p->next_action_time <= G.cur_time) {
+ if (p->p_fd == -1) {
+ /* Time to send new req */
+ if (--cnt == 0) {
+ VERB4 bb_error_msg("disabling burst mode");
+ G.polladj_count = 0;
+ G.poll_exp = MINPOLL;
+ }
+ send_query_to_peer(p);
+ } else {
+ /* Timed out waiting for reply */
+ close(p->p_fd);
+ p->p_fd = -1;
+ /* If poll interval is small, increase it */
+ if (G.poll_exp < BIGPOLL)
+ adjust_poll(MINPOLL);
+ timeout = poll_interval(NOREPLY_INTERVAL);
+ bb_error_msg("timed out waiting for %s, reach 0x%02x, next query in %us",
+ p->p_dotted, p->reachable_bits, timeout);
+
+ /* What if don't see it because it changed its IP? */
+ if (p->reachable_bits == 0)
+ resolve_peer_hostname(p);
+
+ set_next(p, timeout);
}
- send_query_to_peer(p);
- } else {
- /* Timed out waiting for reply */
- close(p->p_fd);
- p->p_fd = -1;
- /* If poll interval is small, increase it */
- if (G.poll_exp < BIGPOLL)
- adjust_poll(MINPOLL);
- timeout = poll_interval(NOREPLY_INTERVAL);
- bb_error_msg("timed out waiting for %s, reach 0x%02x, next query in %us",
- p->p_dotted, p->reachable_bits, timeout);
-
- /* What if don't see it because it changed its IP? */
- if (p->reachable_bits == 0)
- resolve_peer_hostname(p, /*loop_on_fail=*/ 0);
-
- set_next(p, timeout);
}
- }
+
+ if (p->p_fd >= 0) {
+ /* Wait for reply from this peer */
+ pfd[i].fd = p->p_fd;
+ pfd[i].events = POLLIN;
+ idx2peer[i] = p;
+ i++;
+ }
+
+ } else
+ resolve_peer_hostname(p);
if (p->next_action_time < nextaction)
nextaction = p->next_action_time;
- if (p->p_fd >= 0) {
- /* Wait for reply from this peer */
- pfd[i].fd = p->p_fd;
- pfd[i].events = POLLIN;
- idx2peer[i] = p;
- i++;
- }
}
timeout = nextaction - G.cur_time;
--
2.9.1
|
