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
|
/* Generic write queue implementation */
/*
* (C) 2010 by Holger Hans Peter Freyther
* (C) 2010 by On-Waves
*
* All Rights Reserved
*
* 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 2 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, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*
*/
#include <errno.h>
#include <osmocom/core/write_queue.h>
/*! \addtogroup write_queue
* @{
*/
/*! \file write_queue.c */
/*! \brief Select loop function for write queue handling
* \param[in] fd osmocom file descriptor
* \param[in] what bit-mask of events that have happened
*
* This function is provided so that it can be registered with the
* select loop abstraction code (\ref osmo_fd::cb).
*/
int osmo_wqueue_bfd_cb(struct osmo_fd *fd, unsigned int what)
{
struct osmo_wqueue *queue;
int rc;
queue = container_of(fd, struct osmo_wqueue, bfd);
if (what & BSC_FD_READ) {
rc = queue->read_cb(fd);
if (rc == -EBADF)
goto err_badfd;
}
if (what & BSC_FD_EXCEPT) {
rc = queue->except_cb(fd);
if (rc == -EBADF)
goto err_badfd;
}
if (what & BSC_FD_WRITE) {
struct msgb *msg;
fd->when &= ~BSC_FD_WRITE;
/* the queue might have been emptied */
if (!llist_empty(&queue->msg_queue)) {
--queue->current_length;
msg = msgb_dequeue(&queue->msg_queue);
rc = queue->write_cb(fd, msg);
msgb_free(msg);
if (rc == -EBADF)
goto err_badfd;
if (!llist_empty(&queue->msg_queue))
fd->when |= BSC_FD_WRITE;
}
}
err_badfd:
/* Return value is not checked in osmo_select_main() */
return 0;
}
/*! \brief Initialize a \ref osmo_wqueue structure
* \param[in] queue Write queue to operate on
* \param[in] max_length Maximum length of write queue
*/
void osmo_wqueue_init(struct osmo_wqueue *queue, int max_length)
{
queue->max_length = max_length;
queue->current_length = 0;
queue->read_cb = NULL;
queue->write_cb = NULL;
queue->bfd.cb = osmo_wqueue_bfd_cb;
INIT_LLIST_HEAD(&queue->msg_queue);
}
/*! \brief Enqueue a new \ref msgb into a write queue
* \param[in] queue Write queue to be used
* \param[in] data to-be-enqueued message buffer
*/
int osmo_wqueue_enqueue(struct osmo_wqueue *queue, struct msgb *data)
{
// if (queue->current_length + 1 >= queue->max_length)
// LOGP(DMSC, LOGL_ERROR, "The queue is full. Dropping not yet implemented.\n");
++queue->current_length;
msgb_enqueue(&queue->msg_queue, data);
queue->bfd.when |= BSC_FD_WRITE;
return 0;
}
/*! \brief Clear a \ref osmo_wqueue
* \param[in] queue Write queue to be cleared
*
* This function will clear (remove/release) all messages in it.
*/
void osmo_wqueue_clear(struct osmo_wqueue *queue)
{
while (!llist_empty(&queue->msg_queue)) {
struct msgb *msg = msgb_dequeue(&queue->msg_queue);
msgb_free(msg);
}
queue->current_length = 0;
queue->bfd.when &= ~BSC_FD_WRITE;
}
/*! @} */
|
