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git.proxmox.com Git - mirror_frr.git/blob - lib/imsg-buffer.c
4 * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
24 static int ibuf_realloc(struct ibuf
*, size_t);
25 static void ibuf_enqueue(struct msgbuf
*, struct ibuf
*);
26 static void ibuf_dequeue(struct msgbuf
*, struct ibuf
*);
28 struct ibuf
*ibuf_open(size_t len
)
32 if ((buf
= calloc(1, sizeof(struct ibuf
))) == NULL
)
34 if ((buf
->buf
= malloc(len
)) == NULL
) {
38 buf
->size
= buf
->max
= len
;
44 struct ibuf
*ibuf_dynamic(size_t len
, size_t max
)
51 if ((buf
= ibuf_open(len
)) == NULL
)
60 static int ibuf_realloc(struct ibuf
*buf
, size_t len
)
64 /* on static buffers max is eq size and so the following fails */
65 if (buf
->wpos
+ len
> buf
->max
) {
70 b
= realloc(buf
->buf
, buf
->wpos
+ len
);
74 buf
->size
= buf
->wpos
+ len
;
79 int ibuf_add(struct ibuf
*buf
, const void *data
, size_t len
)
81 if (buf
->wpos
+ len
> buf
->size
)
82 if (ibuf_realloc(buf
, len
) == -1)
85 memcpy(buf
->buf
+ buf
->wpos
, data
, len
);
90 void *ibuf_reserve(struct ibuf
*buf
, size_t len
)
94 if (buf
->wpos
+ len
> buf
->size
)
95 if (ibuf_realloc(buf
, len
) == -1)
98 b
= buf
->buf
+ buf
->wpos
;
103 void *ibuf_seek(struct ibuf
*buf
, size_t pos
, size_t len
)
105 /* only allowed to seek in already written parts */
106 if (pos
+ len
> buf
->wpos
)
109 return (buf
->buf
+ pos
);
112 size_t ibuf_size(struct ibuf
*buf
)
117 size_t ibuf_left(struct ibuf
*buf
)
119 return (buf
->max
- buf
->wpos
);
122 void ibuf_close(struct msgbuf
*msgbuf
, struct ibuf
*buf
)
124 ibuf_enqueue(msgbuf
, buf
);
127 int ibuf_write(struct msgbuf
*msgbuf
)
129 struct iovec iov
[IOV_MAX
];
134 memset(&iov
, 0, sizeof(iov
));
135 TAILQ_FOREACH (buf
, &msgbuf
->bufs
, entry
) {
138 iov
[i
].iov_base
= buf
->buf
+ buf
->rpos
;
139 iov
[i
].iov_len
= buf
->wpos
- buf
->rpos
;
144 if ((n
= writev(msgbuf
->fd
, iov
, i
)) == -1) {
147 if (errno
== ENOBUFS
)
152 if (n
== 0) { /* connection closed */
157 msgbuf_drain(msgbuf
, n
);
162 void ibuf_free(struct ibuf
*buf
)
170 void msgbuf_init(struct msgbuf
*msgbuf
)
174 TAILQ_INIT(&msgbuf
->bufs
);
177 void msgbuf_drain(struct msgbuf
*msgbuf
, size_t n
)
179 struct ibuf
*buf
, *next
;
181 for (buf
= TAILQ_FIRST(&msgbuf
->bufs
); buf
!= NULL
&& n
> 0;
183 next
= TAILQ_NEXT(buf
, entry
);
184 if (buf
->rpos
+ n
>= buf
->wpos
) {
185 n
-= buf
->wpos
- buf
->rpos
;
187 TAILQ_REMOVE(&msgbuf
->bufs
, buf
, entry
);
188 ibuf_dequeue(msgbuf
, buf
);
196 void msgbuf_clear(struct msgbuf
*msgbuf
)
200 while ((buf
= TAILQ_POP_FIRST(&msgbuf
->bufs
, entry
)) != NULL
)
201 ibuf_dequeue(msgbuf
, buf
);
204 int msgbuf_write(struct msgbuf
*msgbuf
)
206 struct iovec iov
[IOV_MAX
];
211 struct cmsghdr
*cmsg
;
214 char buf
[CMSG_SPACE(sizeof(int))];
217 memset(&iov
, 0, sizeof(iov
));
218 memset(&msg
, 0, sizeof(msg
));
219 memset(&cmsgbuf
, 0, sizeof(cmsgbuf
));
220 TAILQ_FOREACH (buf
, &msgbuf
->bufs
, entry
) {
223 iov
[i
].iov_base
= buf
->buf
+ buf
->rpos
;
224 iov
[i
].iov_len
= buf
->wpos
- buf
->rpos
;
233 if (buf
!= NULL
&& buf
->fd
!= -1) {
234 msg
.msg_control
= (caddr_t
)&cmsgbuf
.buf
;
235 msg
.msg_controllen
= sizeof(cmsgbuf
.buf
);
236 cmsg
= CMSG_FIRSTHDR(&msg
);
237 cmsg
->cmsg_len
= CMSG_LEN(sizeof(int));
238 cmsg
->cmsg_level
= SOL_SOCKET
;
239 cmsg
->cmsg_type
= SCM_RIGHTS
;
240 memcpy(CMSG_DATA(cmsg
), &buf
->fd
, sizeof(int));
244 if ((n
= sendmsg(msgbuf
->fd
, &msg
, 0)) == -1) {
247 if (errno
== ENOBUFS
)
252 if (n
== 0) { /* connection closed */
258 * assumption: fd got sent if sendmsg sent anything
259 * this works because fds are passed one at a time
261 if (buf
!= NULL
&& buf
->fd
!= -1) {
266 msgbuf_drain(msgbuf
, n
);
271 static void ibuf_enqueue(struct msgbuf
*msgbuf
, struct ibuf
*buf
)
273 TAILQ_INSERT_TAIL(&msgbuf
->bufs
, buf
, entry
);
277 static void ibuf_dequeue(struct msgbuf
*msgbuf
, struct ibuf
*buf
)
279 /* TAILQ_REMOVE done by caller */