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#include <u.h>
#define NOPLAN9DEFINES
#include <libc.h>
#include <sys/socket.h>
#include <sys/uio.h>
#include <unistd.h>
#include <errno.h>
#ifndef CMSG_ALIGN
# ifdef __sun__
# define CMSG_ALIGN _CMSG_DATA_ALIGN
# else
# define CMSG_ALIGN(len) (((len)+sizeof(long)-1) & ~(sizeof(long)-1))
# endif
#endif
#ifndef CMSG_SPACE
# define CMSG_SPACE(len) (CMSG_ALIGN(sizeof(struct cmsghdr))+CMSG_ALIGN(len))
#endif
#ifndef CMSG_LEN
# define CMSG_LEN(len) (CMSG_ALIGN(sizeof(struct cmsghdr))+(len))
#endif
int
sendfd(int s, int fd)
{
char buf[1];
struct iovec iov;
struct msghdr msg;
struct cmsghdr *cmsg;
int n;
char cms[CMSG_SPACE(sizeof(int))];
buf[0] = 0;
iov.iov_base = buf;
iov.iov_len = 1;
memset(&msg, 0, sizeof msg);
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
msg.msg_control = (caddr_t)cms;
msg.msg_controllen = CMSG_LEN(sizeof(int));
cmsg = CMSG_FIRSTHDR(&msg);
cmsg->cmsg_len = CMSG_LEN(sizeof(int));
cmsg->cmsg_level = SOL_SOCKET;
cmsg->cmsg_type = SCM_RIGHTS;
memmove(CMSG_DATA(cmsg), &fd, sizeof(int));
if((n=sendmsg(s, &msg, 0)) != iov.iov_len)
return -1;
return 0;
}
int
recvfd(int s)
{
int n;
int fd;
char buf[1];
struct iovec iov;
struct msghdr msg;
struct cmsghdr *cmsg;
char cms[CMSG_SPACE(sizeof(int))];
iov.iov_base = buf;
iov.iov_len = 1;
memset(&msg, 0, sizeof msg);
msg.msg_name = 0;
msg.msg_namelen = 0;
msg.msg_iov = &iov;
msg.msg_iovlen = 1;
msg.msg_control = (caddr_t)cms;
msg.msg_controllen = sizeof cms;
if((n=recvmsg(s, &msg, 0)) < 0)
return -1;
if(n == 0){
werrstr("unexpected EOF");
return -1;
}
cmsg = CMSG_FIRSTHDR(&msg);
memmove(&fd, CMSG_DATA(cmsg), sizeof(int));
return fd;
}
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