File: buffer.c

package info (click to toggle)
openntpd 3.9p1-3
  • links: PTS
  • area: main
  • in suites: etch, etch-m68k
  • size: 952 kB
  • ctags: 725
  • sloc: ansic: 4,379; sh: 2,730; yacc: 354; awk: 323; makefile: 218
file content (152 lines) | stat: -rw-r--r-- 3,129 bytes parent folder | download | duplicates (5)
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
/*	$OpenBSD: buffer.c,v 1.9 2005/08/11 16:26:29 henning Exp $ */

/*
 * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
 * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include "includes.h"

#include <sys/types.h>
#include <sys/uio.h>

#include <errno.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "ntpd.h"

void	buf_enqueue(struct msgbuf *, struct buf *);
void	buf_dequeue(struct msgbuf *, struct buf *);

struct buf *
buf_open(size_t len)
{
	struct buf	*buf;

	if ((buf = calloc(1, sizeof(struct buf))) == NULL)
		return (NULL);
	if ((buf->buf = malloc(len)) == NULL) {
		free(buf);
		return (NULL);
	}
	buf->size = len;

	return (buf);
}

int
buf_add(struct buf *buf, void *data, size_t len)
{
	if (buf->wpos + len > buf->size)
		return (-1);

	memcpy(buf->buf + buf->wpos, data, len);
	buf->wpos += len;
	return (0);
}

int
buf_close(struct msgbuf *msgbuf, struct buf *buf)
{
	buf_enqueue(msgbuf, buf);
	return (1);
}

void
buf_free(struct buf *buf)
{
	free(buf->buf);
	free(buf);
}

void
msgbuf_init(struct msgbuf *msgbuf)
{
	msgbuf->queued = 0;
	msgbuf->fd = -1;
	TAILQ_INIT(&msgbuf->bufs);
}

void
msgbuf_clear(struct msgbuf *msgbuf)
{
	struct buf	*buf;

	while ((buf = TAILQ_FIRST(&msgbuf->bufs)) != NULL)
		buf_dequeue(msgbuf, buf);
}

int
msgbuf_write(struct msgbuf *msgbuf)
{
	struct iovec	 iov[IOV_MAX];
	struct buf	*buf, *next;
	int		 i = 0;
	ssize_t		 n;

	bzero(&iov, sizeof(iov));
	TAILQ_FOREACH(buf, &msgbuf->bufs, entry) {
		if (i >= IOV_MAX)
			break;
		iov[i].iov_base = buf->buf + buf->rpos;
		iov[i].iov_len = buf->size - buf->rpos;
		i++;
	}

	if ((n = writev(msgbuf->fd, iov, i)) == -1) {
		if (errno == EAGAIN || errno == EINTR ||
		    errno == ENOBUFS)	/* try again later */
			return (0);
		else
			return (-1);
	}

	if (n == 0) {			/* connection closed */
		errno = 0;
		return (-2);
	}

	for (buf = TAILQ_FIRST(&msgbuf->bufs); buf != NULL && n > 0;
	    buf = next) {
		next = TAILQ_NEXT(buf, entry);
		if (buf->rpos + n >= buf->size) {
			n -= buf->size - buf->rpos;
			buf_dequeue(msgbuf, buf);
		} else {
			buf->rpos += n;
			n = 0;
		}
	}

	return (0);
}

void
buf_enqueue(struct msgbuf *msgbuf, struct buf *buf)
{
	TAILQ_INSERT_TAIL(&msgbuf->bufs, buf, entry);
	msgbuf->queued++;
}

void
buf_dequeue(struct msgbuf *msgbuf, struct buf *buf)
{
	TAILQ_REMOVE(&msgbuf->bufs, buf, entry);
	msgbuf->queued--;
	buf_free(buf);
}