1 12eb29d8 2024-01-07 op /* $OpenBSD: imsg-buffer.c,v 1.18 2023/12/12 15:47:41 claudio Exp $ */
4 12eb29d8 2024-01-07 op * Copyright (c) 2023 Claudio Jeker <claudio@openbsd.org>
5 6b191ed5 2021-02-23 op * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
7 6b191ed5 2021-02-23 op * Permission to use, copy, modify, and distribute this software for any
8 6b191ed5 2021-02-23 op * purpose with or without fee is hereby granted, provided that the above
9 6b191ed5 2021-02-23 op * copyright notice and this permission notice appear in all copies.
11 6b191ed5 2021-02-23 op * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12 6b191ed5 2021-02-23 op * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13 6b191ed5 2021-02-23 op * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14 6b191ed5 2021-02-23 op * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15 6b191ed5 2021-02-23 op * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16 6b191ed5 2021-02-23 op * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17 6b191ed5 2021-02-23 op * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
20 6b191ed5 2021-02-23 op #include "../config.h"
22 6b191ed5 2021-02-23 op #include <sys/types.h>
23 6b191ed5 2021-02-23 op #include <sys/socket.h>
24 6b191ed5 2021-02-23 op #include <sys/uio.h>
26 6b191ed5 2021-02-23 op #include <limits.h>
27 6b191ed5 2021-02-23 op #include <errno.h>
28 12eb29d8 2024-01-07 op #include <stdint.h>
29 6b191ed5 2021-02-23 op #include <stdlib.h>
30 6b191ed5 2021-02-23 op #include <string.h>
31 6b191ed5 2021-02-23 op #include <unistd.h>
33 6b191ed5 2021-02-23 op #include "imsg.h"
35 6b191ed5 2021-02-23 op static int ibuf_realloc(struct ibuf *, size_t);
36 6b191ed5 2021-02-23 op static void ibuf_enqueue(struct msgbuf *, struct ibuf *);
37 6b191ed5 2021-02-23 op static void ibuf_dequeue(struct msgbuf *, struct ibuf *);
38 c9c44c65 2023-07-02 op static void msgbuf_drain(struct msgbuf *, size_t);
41 6b191ed5 2021-02-23 op ibuf_open(size_t len)
43 6b191ed5 2021-02-23 op struct ibuf *buf;
45 c9c44c65 2023-07-02 op if (len == 0) {
46 c9c44c65 2023-07-02 op errno = EINVAL;
47 c9c44c65 2023-07-02 op return (NULL);
49 6b191ed5 2021-02-23 op if ((buf = calloc(1, sizeof(struct ibuf))) == NULL)
50 6b191ed5 2021-02-23 op return (NULL);
51 c9c44c65 2023-07-02 op if ((buf->buf = calloc(len, 1)) == NULL) {
53 6b191ed5 2021-02-23 op return (NULL);
55 6b191ed5 2021-02-23 op buf->size = buf->max = len;
62 6b191ed5 2021-02-23 op ibuf_dynamic(size_t len, size_t max)
64 6b191ed5 2021-02-23 op struct ibuf *buf;
66 12eb29d8 2024-01-07 op if (max == 0 || max < len) {
67 c9c44c65 2023-07-02 op errno = EINVAL;
68 6b191ed5 2021-02-23 op return (NULL);
71 c9c44c65 2023-07-02 op if ((buf = calloc(1, sizeof(struct ibuf))) == NULL)
72 6b191ed5 2021-02-23 op return (NULL);
73 c9c44c65 2023-07-02 op if (len > 0) {
74 c9c44c65 2023-07-02 op if ((buf->buf = calloc(len, 1)) == NULL) {
76 c9c44c65 2023-07-02 op return (NULL);
79 c9c44c65 2023-07-02 op buf->size = len;
80 c9c44c65 2023-07-02 op buf->max = max;
87 6b191ed5 2021-02-23 op ibuf_realloc(struct ibuf *buf, size_t len)
89 6b191ed5 2021-02-23 op unsigned char *b;
91 6b191ed5 2021-02-23 op /* on static buffers max is eq size and so the following fails */
92 c9c44c65 2023-07-02 op if (len > SIZE_MAX - buf->wpos || buf->wpos + len > buf->max) {
93 6b191ed5 2021-02-23 op errno = ERANGE;
97 6b191ed5 2021-02-23 op b = recallocarray(buf->buf, buf->size, buf->wpos + len, 1);
98 6b191ed5 2021-02-23 op if (b == NULL)
100 6b191ed5 2021-02-23 op buf->buf = b;
101 6b191ed5 2021-02-23 op buf->size = buf->wpos + len;
107 6b191ed5 2021-02-23 op ibuf_reserve(struct ibuf *buf, size_t len)
111 12eb29d8 2024-01-07 op if (len > SIZE_MAX - buf->wpos || buf->max == 0) {
112 c9c44c65 2023-07-02 op errno = ERANGE;
113 c9c44c65 2023-07-02 op return (NULL);
116 6b191ed5 2021-02-23 op if (buf->wpos + len > buf->size)
117 6b191ed5 2021-02-23 op if (ibuf_realloc(buf, len) == -1)
118 6b191ed5 2021-02-23 op return (NULL);
120 6b191ed5 2021-02-23 op b = buf->buf + buf->wpos;
121 6b191ed5 2021-02-23 op buf->wpos += len;
126 c9c44c65 2023-07-02 op ibuf_add(struct ibuf *buf, const void *data, size_t len)
130 c9c44c65 2023-07-02 op if ((b = ibuf_reserve(buf, len)) == NULL)
133 c9c44c65 2023-07-02 op memcpy(b, data, len);
138 12eb29d8 2024-01-07 op ibuf_add_ibuf(struct ibuf *buf, const struct ibuf *from)
140 12eb29d8 2024-01-07 op return ibuf_add(buf, ibuf_data(from), ibuf_size(from));
143 12eb29d8 2024-01-07 op /* remove after tree is converted */
145 c9c44c65 2023-07-02 op ibuf_add_buf(struct ibuf *buf, const struct ibuf *from)
147 12eb29d8 2024-01-07 op return ibuf_add_ibuf(buf, from);
151 c9c44c65 2023-07-02 op ibuf_add_n8(struct ibuf *buf, uint64_t value)
155 c9c44c65 2023-07-02 op if (value > UINT8_MAX) {
156 c9c44c65 2023-07-02 op errno = EINVAL;
160 c9c44c65 2023-07-02 op return ibuf_add(buf, &v, sizeof(v));
164 c9c44c65 2023-07-02 op ibuf_add_n16(struct ibuf *buf, uint64_t value)
168 c9c44c65 2023-07-02 op if (value > UINT16_MAX) {
169 c9c44c65 2023-07-02 op errno = EINVAL;
172 c9c44c65 2023-07-02 op v = htobe16(value);
173 c9c44c65 2023-07-02 op return ibuf_add(buf, &v, sizeof(v));
177 c9c44c65 2023-07-02 op ibuf_add_n32(struct ibuf *buf, uint64_t value)
181 c9c44c65 2023-07-02 op if (value > UINT32_MAX) {
182 c9c44c65 2023-07-02 op errno = EINVAL;
185 c9c44c65 2023-07-02 op v = htobe32(value);
186 c9c44c65 2023-07-02 op return ibuf_add(buf, &v, sizeof(v));
190 c9c44c65 2023-07-02 op ibuf_add_n64(struct ibuf *buf, uint64_t value)
192 c9c44c65 2023-07-02 op value = htobe64(value);
193 12eb29d8 2024-01-07 op return ibuf_add(buf, &value, sizeof(value));
197 12eb29d8 2024-01-07 op ibuf_add_h16(struct ibuf *buf, uint64_t value)
201 12eb29d8 2024-01-07 op if (value > UINT16_MAX) {
202 12eb29d8 2024-01-07 op errno = EINVAL;
206 12eb29d8 2024-01-07 op return ibuf_add(buf, &v, sizeof(v));
210 12eb29d8 2024-01-07 op ibuf_add_h32(struct ibuf *buf, uint64_t value)
214 12eb29d8 2024-01-07 op if (value > UINT32_MAX) {
215 12eb29d8 2024-01-07 op errno = EINVAL;
219 12eb29d8 2024-01-07 op return ibuf_add(buf, &v, sizeof(v));
223 12eb29d8 2024-01-07 op ibuf_add_h64(struct ibuf *buf, uint64_t value)
225 c9c44c65 2023-07-02 op return ibuf_add(buf, &value, sizeof(value));
229 c9c44c65 2023-07-02 op ibuf_add_zero(struct ibuf *buf, size_t len)
233 c9c44c65 2023-07-02 op if ((b = ibuf_reserve(buf, len)) == NULL)
235 12eb29d8 2024-01-07 op memset(b, 0, len);
240 6b191ed5 2021-02-23 op ibuf_seek(struct ibuf *buf, size_t pos, size_t len)
242 12eb29d8 2024-01-07 op /* only allow seeking between rpos and wpos */
243 12eb29d8 2024-01-07 op if (ibuf_size(buf) < pos || SIZE_MAX - pos < len ||
244 12eb29d8 2024-01-07 op ibuf_size(buf) < pos + len) {
245 c9c44c65 2023-07-02 op errno = ERANGE;
246 6b191ed5 2021-02-23 op return (NULL);
249 12eb29d8 2024-01-07 op return (buf->buf + buf->rpos + pos);
253 c9c44c65 2023-07-02 op ibuf_set(struct ibuf *buf, size_t pos, const void *data, size_t len)
257 c9c44c65 2023-07-02 op if ((b = ibuf_seek(buf, pos, len)) == NULL)
260 c9c44c65 2023-07-02 op memcpy(b, data, len);
265 c9c44c65 2023-07-02 op ibuf_set_n8(struct ibuf *buf, size_t pos, uint64_t value)
269 c9c44c65 2023-07-02 op if (value > UINT8_MAX) {
270 c9c44c65 2023-07-02 op errno = EINVAL;
274 c9c44c65 2023-07-02 op return (ibuf_set(buf, pos, &v, sizeof(v)));
278 c9c44c65 2023-07-02 op ibuf_set_n16(struct ibuf *buf, size_t pos, uint64_t value)
282 c9c44c65 2023-07-02 op if (value > UINT16_MAX) {
283 c9c44c65 2023-07-02 op errno = EINVAL;
286 c9c44c65 2023-07-02 op v = htobe16(value);
287 c9c44c65 2023-07-02 op return (ibuf_set(buf, pos, &v, sizeof(v)));
291 c9c44c65 2023-07-02 op ibuf_set_n32(struct ibuf *buf, size_t pos, uint64_t value)
295 c9c44c65 2023-07-02 op if (value > UINT32_MAX) {
296 c9c44c65 2023-07-02 op errno = EINVAL;
299 c9c44c65 2023-07-02 op v = htobe32(value);
300 c9c44c65 2023-07-02 op return (ibuf_set(buf, pos, &v, sizeof(v)));
304 c9c44c65 2023-07-02 op ibuf_set_n64(struct ibuf *buf, size_t pos, uint64_t value)
306 c9c44c65 2023-07-02 op value = htobe64(value);
307 c9c44c65 2023-07-02 op return (ibuf_set(buf, pos, &value, sizeof(value)));
311 12eb29d8 2024-01-07 op ibuf_set_h16(struct ibuf *buf, size_t pos, uint64_t value)
315 12eb29d8 2024-01-07 op if (value > UINT16_MAX) {
316 12eb29d8 2024-01-07 op errno = EINVAL;
320 12eb29d8 2024-01-07 op return (ibuf_set(buf, pos, &v, sizeof(v)));
324 12eb29d8 2024-01-07 op ibuf_set_h32(struct ibuf *buf, size_t pos, uint64_t value)
328 12eb29d8 2024-01-07 op if (value > UINT32_MAX) {
329 12eb29d8 2024-01-07 op errno = EINVAL;
333 12eb29d8 2024-01-07 op return (ibuf_set(buf, pos, &v, sizeof(v)));
337 12eb29d8 2024-01-07 op ibuf_set_h64(struct ibuf *buf, size_t pos, uint64_t value)
339 12eb29d8 2024-01-07 op return (ibuf_set(buf, pos, &value, sizeof(value)));
343 12eb29d8 2024-01-07 op ibuf_data(const struct ibuf *buf)
345 12eb29d8 2024-01-07 op return (buf->buf + buf->rpos);
349 12eb29d8 2024-01-07 op ibuf_size(const struct ibuf *buf)
351 12eb29d8 2024-01-07 op return (buf->wpos - buf->rpos);
355 12eb29d8 2024-01-07 op ibuf_left(const struct ibuf *buf)
357 12eb29d8 2024-01-07 op if (buf->max == 0)
359 6b191ed5 2021-02-23 op return (buf->max - buf->wpos);
363 12eb29d8 2024-01-07 op ibuf_truncate(struct ibuf *buf, size_t len)
365 12eb29d8 2024-01-07 op if (ibuf_size(buf) >= len) {
366 12eb29d8 2024-01-07 op buf->wpos = buf->rpos + len;
369 12eb29d8 2024-01-07 op if (buf->max == 0) {
370 12eb29d8 2024-01-07 op /* only allow to truncate down */
371 12eb29d8 2024-01-07 op errno = ERANGE;
374 12eb29d8 2024-01-07 op return ibuf_add_zero(buf, len - ibuf_size(buf));
378 12eb29d8 2024-01-07 op ibuf_rewind(struct ibuf *buf)
380 12eb29d8 2024-01-07 op buf->rpos = 0;
384 6b191ed5 2021-02-23 op ibuf_close(struct msgbuf *msgbuf, struct ibuf *buf)
386 6b191ed5 2021-02-23 op ibuf_enqueue(msgbuf, buf);
390 12eb29d8 2024-01-07 op ibuf_from_buffer(struct ibuf *buf, void *data, size_t len)
392 12eb29d8 2024-01-07 op memset(buf, 0, sizeof(*buf));
393 12eb29d8 2024-01-07 op buf->buf = data;
394 12eb29d8 2024-01-07 op buf->size = buf->wpos = len;
395 12eb29d8 2024-01-07 op buf->fd = -1;
399 12eb29d8 2024-01-07 op ibuf_from_ibuf(struct ibuf *buf, const struct ibuf *from)
401 12eb29d8 2024-01-07 op ibuf_from_buffer(buf, ibuf_data(from), ibuf_size(from));
405 12eb29d8 2024-01-07 op ibuf_get(struct ibuf *buf, void *data, size_t len)
407 12eb29d8 2024-01-07 op if (ibuf_size(buf) < len) {
408 12eb29d8 2024-01-07 op errno = EBADMSG;
412 12eb29d8 2024-01-07 op memcpy(data, ibuf_data(buf), len);
413 12eb29d8 2024-01-07 op buf->rpos += len;
418 12eb29d8 2024-01-07 op ibuf_get_ibuf(struct ibuf *buf, size_t len, struct ibuf *new)
420 12eb29d8 2024-01-07 op if (ibuf_size(buf) < len) {
421 12eb29d8 2024-01-07 op errno = EBADMSG;
425 12eb29d8 2024-01-07 op ibuf_from_buffer(new, ibuf_data(buf), len);
426 12eb29d8 2024-01-07 op buf->rpos += len;
431 12eb29d8 2024-01-07 op ibuf_get_n8(struct ibuf *buf, uint8_t *value)
433 12eb29d8 2024-01-07 op return ibuf_get(buf, value, sizeof(*value));
437 12eb29d8 2024-01-07 op ibuf_get_n16(struct ibuf *buf, uint16_t *value)
441 12eb29d8 2024-01-07 op rv = ibuf_get(buf, value, sizeof(*value));
442 12eb29d8 2024-01-07 op *value = be16toh(*value);
447 12eb29d8 2024-01-07 op ibuf_get_n32(struct ibuf *buf, uint32_t *value)
451 12eb29d8 2024-01-07 op rv = ibuf_get(buf, value, sizeof(*value));
452 12eb29d8 2024-01-07 op *value = be32toh(*value);
457 12eb29d8 2024-01-07 op ibuf_get_n64(struct ibuf *buf, uint64_t *value)
461 12eb29d8 2024-01-07 op rv = ibuf_get(buf, value, sizeof(*value));
462 12eb29d8 2024-01-07 op *value = be64toh(*value);
467 12eb29d8 2024-01-07 op ibuf_get_h16(struct ibuf *buf, uint16_t *value)
469 12eb29d8 2024-01-07 op return ibuf_get(buf, value, sizeof(*value));
473 12eb29d8 2024-01-07 op ibuf_get_h32(struct ibuf *buf, uint32_t *value)
475 12eb29d8 2024-01-07 op return ibuf_get(buf, value, sizeof(*value));
479 12eb29d8 2024-01-07 op ibuf_get_h64(struct ibuf *buf, uint64_t *value)
481 12eb29d8 2024-01-07 op return ibuf_get(buf, value, sizeof(*value));
485 12eb29d8 2024-01-07 op ibuf_skip(struct ibuf *buf, size_t len)
487 12eb29d8 2024-01-07 op if (ibuf_size(buf) < len) {
488 12eb29d8 2024-01-07 op errno = EBADMSG;
492 12eb29d8 2024-01-07 op buf->rpos += len;
497 c9c44c65 2023-07-02 op ibuf_free(struct ibuf *buf)
499 c9c44c65 2023-07-02 op if (buf == NULL)
501 12eb29d8 2024-01-07 op if (buf->max == 0) /* if buf lives on the stack */
502 12eb29d8 2024-01-07 op abort(); /* abort before causing more harm */
503 c9c44c65 2023-07-02 op if (buf->fd != -1)
504 c9c44c65 2023-07-02 op close(buf->fd);
505 c9c44c65 2023-07-02 op freezero(buf->buf, buf->size);
510 c9c44c65 2023-07-02 op ibuf_fd_avail(struct ibuf *buf)
512 c9c44c65 2023-07-02 op return (buf->fd != -1);
516 c9c44c65 2023-07-02 op ibuf_fd_get(struct ibuf *buf)
520 c9c44c65 2023-07-02 op fd = buf->fd;
521 c9c44c65 2023-07-02 op buf->fd = -1;
526 c9c44c65 2023-07-02 op ibuf_fd_set(struct ibuf *buf, int fd)
528 12eb29d8 2024-01-07 op if (buf->max == 0) /* if buf lives on the stack */
529 12eb29d8 2024-01-07 op abort(); /* abort before causing more harm */
530 c9c44c65 2023-07-02 op if (buf->fd != -1)
531 c9c44c65 2023-07-02 op close(buf->fd);
532 c9c44c65 2023-07-02 op buf->fd = fd;
536 6b191ed5 2021-02-23 op ibuf_write(struct msgbuf *msgbuf)
538 6b191ed5 2021-02-23 op struct iovec iov[IOV_MAX];
539 6b191ed5 2021-02-23 op struct ibuf *buf;
540 6b191ed5 2021-02-23 op unsigned int i = 0;
543 6b191ed5 2021-02-23 op memset(&iov, 0, sizeof(iov));
544 6b191ed5 2021-02-23 op TAILQ_FOREACH(buf, &msgbuf->bufs, entry) {
545 6b191ed5 2021-02-23 op if (i >= IOV_MAX)
547 12eb29d8 2024-01-07 op iov[i].iov_base = ibuf_data(buf);
548 12eb29d8 2024-01-07 op iov[i].iov_len = ibuf_size(buf);
553 6b191ed5 2021-02-23 op if ((n = writev(msgbuf->fd, iov, i)) == -1) {
554 6b191ed5 2021-02-23 op if (errno == EINTR)
556 6b191ed5 2021-02-23 op if (errno == ENOBUFS)
557 6b191ed5 2021-02-23 op errno = EAGAIN;
561 6b191ed5 2021-02-23 op if (n == 0) { /* connection closed */
566 6b191ed5 2021-02-23 op msgbuf_drain(msgbuf, n);
572 6b191ed5 2021-02-23 op msgbuf_init(struct msgbuf *msgbuf)
574 6b191ed5 2021-02-23 op msgbuf->queued = 0;
575 6b191ed5 2021-02-23 op msgbuf->fd = -1;
576 6b191ed5 2021-02-23 op TAILQ_INIT(&msgbuf->bufs);
580 6b191ed5 2021-02-23 op msgbuf_drain(struct msgbuf *msgbuf, size_t n)
582 6b191ed5 2021-02-23 op struct ibuf *buf, *next;
584 6b191ed5 2021-02-23 op for (buf = TAILQ_FIRST(&msgbuf->bufs); buf != NULL && n > 0;
585 6b191ed5 2021-02-23 op buf = next) {
586 6b191ed5 2021-02-23 op next = TAILQ_NEXT(buf, entry);
587 12eb29d8 2024-01-07 op if (n >= ibuf_size(buf)) {
588 12eb29d8 2024-01-07 op n -= ibuf_size(buf);
589 6b191ed5 2021-02-23 op ibuf_dequeue(msgbuf, buf);
591 6b191ed5 2021-02-23 op buf->rpos += n;
598 6b191ed5 2021-02-23 op msgbuf_clear(struct msgbuf *msgbuf)
600 6b191ed5 2021-02-23 op struct ibuf *buf;
602 6b191ed5 2021-02-23 op while ((buf = TAILQ_FIRST(&msgbuf->bufs)) != NULL)
603 6b191ed5 2021-02-23 op ibuf_dequeue(msgbuf, buf);
607 6b191ed5 2021-02-23 op msgbuf_write(struct msgbuf *msgbuf)
609 6b191ed5 2021-02-23 op struct iovec iov[IOV_MAX];
610 894e9984 2022-03-19 op struct ibuf *buf, *buf0 = NULL;
611 6b191ed5 2021-02-23 op unsigned int i = 0;
613 6b191ed5 2021-02-23 op struct msghdr msg;
614 6b191ed5 2021-02-23 op struct cmsghdr *cmsg;
616 6b191ed5 2021-02-23 op struct cmsghdr hdr;
617 6b191ed5 2021-02-23 op char buf[CMSG_SPACE(sizeof(int))];
620 6b191ed5 2021-02-23 op memset(&iov, 0, sizeof(iov));
621 6b191ed5 2021-02-23 op memset(&msg, 0, sizeof(msg));
622 6b191ed5 2021-02-23 op memset(&cmsgbuf, 0, sizeof(cmsgbuf));
623 6b191ed5 2021-02-23 op TAILQ_FOREACH(buf, &msgbuf->bufs, entry) {
624 6b191ed5 2021-02-23 op if (i >= IOV_MAX)
626 894e9984 2022-03-19 op if (i > 0 && buf->fd != -1)
628 12eb29d8 2024-01-07 op iov[i].iov_base = ibuf_data(buf);
629 12eb29d8 2024-01-07 op iov[i].iov_len = ibuf_size(buf);
631 6b191ed5 2021-02-23 op if (buf->fd != -1)
635 6b191ed5 2021-02-23 op msg.msg_iov = iov;
636 6b191ed5 2021-02-23 op msg.msg_iovlen = i;
638 894e9984 2022-03-19 op if (buf0 != NULL) {
639 6b191ed5 2021-02-23 op msg.msg_control = (caddr_t)&cmsgbuf.buf;
640 6b191ed5 2021-02-23 op msg.msg_controllen = sizeof(cmsgbuf.buf);
641 6b191ed5 2021-02-23 op cmsg = CMSG_FIRSTHDR(&msg);
642 6b191ed5 2021-02-23 op cmsg->cmsg_len = CMSG_LEN(sizeof(int));
643 6b191ed5 2021-02-23 op cmsg->cmsg_level = SOL_SOCKET;
644 6b191ed5 2021-02-23 op cmsg->cmsg_type = SCM_RIGHTS;
645 894e9984 2022-03-19 op *(int *)CMSG_DATA(cmsg) = buf0->fd;
649 6b191ed5 2021-02-23 op if ((n = sendmsg(msgbuf->fd, &msg, 0)) == -1) {
650 6b191ed5 2021-02-23 op if (errno == EINTR)
652 6b191ed5 2021-02-23 op if (errno == ENOBUFS)
653 6b191ed5 2021-02-23 op errno = EAGAIN;
657 6b191ed5 2021-02-23 op if (n == 0) { /* connection closed */
663 6b191ed5 2021-02-23 op * assumption: fd got sent if sendmsg sent anything
664 6b191ed5 2021-02-23 op * this works because fds are passed one at a time
666 894e9984 2022-03-19 op if (buf0 != NULL) {
667 894e9984 2022-03-19 op close(buf0->fd);
668 894e9984 2022-03-19 op buf0->fd = -1;
671 6b191ed5 2021-02-23 op msgbuf_drain(msgbuf, n);
677 12eb29d8 2024-01-07 op msgbuf_queuelen(struct msgbuf *msgbuf)
679 12eb29d8 2024-01-07 op return (msgbuf->queued);
683 6b191ed5 2021-02-23 op ibuf_enqueue(struct msgbuf *msgbuf, struct ibuf *buf)
685 12eb29d8 2024-01-07 op if (buf->max == 0) /* if buf lives on the stack */
686 12eb29d8 2024-01-07 op abort(); /* abort before causing more harm */
687 6b191ed5 2021-02-23 op TAILQ_INSERT_TAIL(&msgbuf->bufs, buf, entry);
688 6b191ed5 2021-02-23 op msgbuf->queued++;
692 6b191ed5 2021-02-23 op ibuf_dequeue(struct msgbuf *msgbuf, struct ibuf *buf)
694 6b191ed5 2021-02-23 op TAILQ_REMOVE(&msgbuf->bufs, buf, entry);
695 6b191ed5 2021-02-23 op msgbuf->queued--;
696 6b191ed5 2021-02-23 op ibuf_free(buf);