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
|
#include <sys/socket.h>
#include <errno.h>
#include <stdlib.h>
#include "events.h"
#include "network.h"
struct accept_cookie {
int (* callback)(void *, int);
void * cookie;
int fd;
};
/* Accept the connection and invoke the callback. */
static int
callback_accept(void * cookie)
{
struct accept_cookie * C = cookie;
int s;
int rc;
/* Attempt to accept a new connection. */
if ((s = accept(C->fd, NULL, NULL)) == -1) {
/* If a connection isn't available, reset the callback. */
if ((errno == EAGAIN) ||
#if EAGAIN != EWOULDBLOCK
(errno == EWOULDBLOCK) ||
#endif
(errno == ECONNABORTED) ||
(errno == EINTR))
goto tryagain;
}
/* Call the upstream callback. */
rc = (C->callback)(C->cookie, s);
/* Free the cookie. */
free(C);
/* Return status from upstream callback. */
return (rc);
tryagain:
/* Reset the callback. */
return (events_network_register(callback_accept, C, C->fd,
EVENTS_NETWORK_OP_READ));
}
/**
* network_accept(fd, callback, cookie):
* Asynchronously accept a connection on the socket ${fd}, which must be
* already marked as listening and non-blocking. When a connection has been
* accepted or an error occurs, invoke ${callback}(${cookie}, s) where s is
* the accepted connection or -1 on error. Return a cookie which can be
* passed to network_accept_cancel() in order to cancel the accept.
*/
void *
network_accept(int fd, int (* callback)(void *, int), void * cookie)
{
struct accept_cookie * C;
/* Bake a cookie. */
if ((C = malloc(sizeof(struct accept_cookie))) == NULL)
goto err0;
C->callback = callback;
C->cookie = cookie;
C->fd = fd;
/*
* Register a network event. A connection arriving on a listening
* socket is treated by select(2) as the socket becoming readable.
*/
if (events_network_register(callback_accept, C, C->fd,
EVENTS_NETWORK_OP_READ))
goto err1;
/* Success! */
return (C);
err1:
free(C);
err0:
/* Failure! */
return (NULL);
}
/**
* network_accept_cancel(cookie):
* Cancel the connection accept for which the cookie ${cookie} was returned
* by network_accept(). Do not invoke the callback associated with the accept.
*/
void
network_accept_cancel(void * cookie)
{
struct accept_cookie * C = cookie;
/* Cancel the network event. */
events_network_cancel(C->fd, EVENTS_NETWORK_OP_READ);
/* Free the cookie. */
free(C);
}
|
