1 /**
2  * \file socket.c
3  * \brief Socket helper routines
4  * \author Abramo Bagnara <abramo@alsa-project.org>
5  * \date 2003
6  */
7 /*
8  *  Socket helper routines
9  *  Copyright (c) 2003 by Abramo Bagnara <abramo@alsa-project.org>
10  *
11  *
12  *   This library is free software; you can redistribute it and/or modify
13  *   it under the terms of the GNU Lesser General Public License as
14  *   published by the Free Software Foundation; either version 2.1 of
15  *   the License, or (at your option) any later version.
16  *
17  *   This program is distributed in the hope that it will be useful,
18  *   but WITHOUT ANY WARRANTY; without even the implied warranty of
19  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
20  *   GNU Lesser General Public License for more details.
21  *
22  *   You should have received a copy of the GNU Lesser General Public
23  *   License along with this library; if not, write to the Free Software
24  *   Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
25  *
26  */
27 
28 #include <stdio.h>
29 #include <stdlib.h>
30 #include <stddef.h>
31 #include <unistd.h>
32 #include <string.h>
33 #include <sys/socket.h>
34 #include <sys/uio.h>
35 #include <sys/un.h>
36 #include <netinet/in.h>
37 #include <sys/ioctl.h>
38 #include <net/if.h>
39 #include <netdb.h>
40 #include "local.h"
41 
42 #ifndef DOC_HIDDEN
snd_send_fd(int sock,void * data,size_t len,int fd)43 int snd_send_fd(int sock, void *data, size_t len, int fd)
44 {
45 	int ret;
46 	size_t cmsg_len = CMSG_LEN(sizeof(int));
47 	struct cmsghdr *cmsg = alloca(cmsg_len);
48 	int *fds = (int *) CMSG_DATA(cmsg);
49 	struct msghdr msghdr;
50 	struct iovec vec;
51 
52 	vec.iov_base = (void *)&data;
53 	vec.iov_len = len;
54 
55 	cmsg->cmsg_len = cmsg_len;
56 	cmsg->cmsg_level = SOL_SOCKET;
57 	cmsg->cmsg_type = SCM_RIGHTS;
58 	*fds = fd;
59 
60 	msghdr.msg_name = NULL;
61 	msghdr.msg_namelen = 0;
62 	msghdr.msg_iov = &vec;
63  	msghdr.msg_iovlen = 1;
64 	msghdr.msg_control = cmsg;
65 	msghdr.msg_controllen = cmsg_len;
66 	msghdr.msg_flags = 0;
67 
68 	ret = sendmsg(sock, &msghdr, 0 );
69 	if (ret < 0) {
70 		SYSERR("sendmsg failed");
71 		return -errno;
72 	}
73 	return ret;
74 }
75 
snd_receive_fd(int sock,void * data,size_t len,int * fd)76 int snd_receive_fd(int sock, void *data, size_t len, int *fd)
77 {
78 	int ret;
79 	size_t cmsg_len = CMSG_LEN(sizeof(int));
80 	struct cmsghdr *cmsg = alloca(cmsg_len);
81 	int *fds = (int *) CMSG_DATA(cmsg);
82 	struct msghdr msghdr;
83 	struct iovec vec;
84 
85 	vec.iov_base = (void *)&data;
86 	vec.iov_len = len;
87 
88 	cmsg->cmsg_len = cmsg_len;
89 	cmsg->cmsg_level = SOL_SOCKET;
90 	cmsg->cmsg_type = SCM_RIGHTS;
91 	*fds = -1;
92 
93 	msghdr.msg_name = NULL;
94 	msghdr.msg_namelen = 0;
95 	msghdr.msg_iov = &vec;
96 	msghdr.msg_iovlen = 1;
97 	msghdr.msg_control = cmsg;
98 	msghdr.msg_controllen = cmsg_len;
99 	msghdr.msg_flags = 0;
100 
101 	ret = recvmsg(sock, &msghdr, 0);
102 	if (ret < 0) {
103 		SYSERR("recvmsg failed");
104 		return -errno;
105 	}
106 	*fd = *fds;
107 	return ret;
108 }
109 #endif
110