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
|
/* Copyright (C) 2011 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz>
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/*!
* \file fdset.h
*
* \author Marek Vavrusa <marek.vavrusa@nic.cz>
*
* \brief I/O multiplexing with context and timeouts for each fd.
*
* \addtogroup common_lib
* @{
*/
#ifndef _KNOTD_FDSET_H_
#define _KNOTD_FDSET_H_
#include <config.h>
#include <stddef.h>
#include <poll.h>
#include <sys/time.h>
#include <signal.h>
#define FDSET_INIT_SIZE 256 /* Resize step. */
/*! \brief Set of filedescriptors with associated context and timeouts. */
typedef struct fdset {
unsigned n; /*!< Active fds. */
unsigned size; /*!< Array size (allocated). */
void* *ctx; /*!< Context for each fd. */
struct pollfd *pfd; /*!< poll state for each fd */
time_t *timeout; /*!< Timeout for each fd (seconds precision). */
} fdset_t;
/*! \brief Mark-and-sweep state. */
enum fdset_sweep_state {
FDSET_KEEP,
FDSET_SWEEP
};
/*! \brief Sweep callback (set, index, data) */
typedef enum fdset_sweep_state (*fdset_sweep_cb_t)(fdset_t*, int, void*);
/*!
* \brief Initialize fdset to given size.
*/
int fdset_init(fdset_t *set, unsigned size);
/*!
* \brief Destroy FDSET.
*
* \retval 0 if successful.
* \retval -1 on error.
*/
int fdset_clear(fdset_t* set);
/*!
* \brief Add file descriptor to watched set.
*
* \param set Target set.
* \param fd Added file descriptor.
* \param events Mask of watched events.
* \param ctx Context (optional).
*
* \retval index of the added fd if successful.
* \retval -1 on errors.
*/
int fdset_add(fdset_t *set, int fd, unsigned events, void *ctx);
/*!
* \brief Remove file descriptor from watched set.
*
* \param set Target set.
* \param i Index of the removed fd.
*
* \retval 0 if successful.
* \retval -1 on errors.
*/
int fdset_remove(fdset_t *set, unsigned i);
/*!
* \brief Set file descriptor watchdog interval.
*
* Set time (interval from now) after which the associated file descriptor
* should be sweeped (see fdset_sweep). Good example is setting a grace period
* of N seconds between socket activity. If socket is not active within
* <now, now + interval>, it is sweeped and potentially closed.
*
* \param set Target set.
* \param i Index for the file descriptor.
* \param interval Allowed interval without activity (seconds).
* -1 disables watchdog timer
*
* \retval 0 if successful.
* \retval -1 on errors.
*/
int fdset_set_watchdog(fdset_t* set, int i, int interval);
/*!
* \brief Sweep file descriptors with exceeding inactivity period.
*
* \param fdset Target set.
* \param cb Callback for sweeped descriptors.
* \param data Pointer to extra data.
*
* \retval number of sweeped descriptors.
* \retval -1 on errors.
*/
int fdset_sweep(fdset_t* set, fdset_sweep_cb_t cb, void *data);
/*!
* \brief pselect(2) compatibility wrapper.
* \param n Number of file descriptors.
* \param readfds Array of fds to read.
* \param writefds Array of fds to write.
* \param exceptfds Array of fds for exceptions.
* \param timeout Upper bound of time elapsed.
* \param sigmask If != NULL, replaces current signal mask.
* \return Number of events or -1 if fails.
*/
int fdset_pselect(int n, fd_set *readfds, fd_set *writefds, fd_set *exceptfds,
const struct timespec *timeout, const sigset_t *sigmask);
#endif /* _KNOTD_FDSET_H_ */
/*! @} */
|
