/*  * This file is part of the UCB release of Plan 9. It is subject to the license * terms in the LICENSE file found in the top-level directory of this * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No * part of the UCB release of Plan 9, including this file, may be copied, * modified, propagated, or distributed except according to the terms contained * in the LICENSE file. */ /* posix */#include <sys/types.h>#include <unistd.h>#include <stdlib.h>#include <stdio.h>#include <fcntl.h>#include <errno.h>#include <string.h>#include <sys/stat.h> /* bsd extensions */#include <sys/uio.h>#include <sys/socket.h>#include <netinet/in.h>#include <sys/un.h> #include "priv.h" intaccept(int fd, void *a, int *alen){	int n, nfd, cfd;	Rock *r, *nr;	struct sockaddr_in *ip;	char name[Ctlsize];	char file[8+Ctlsize+1];	char *net; 	r = _sock_findrock(fd, 0);	if(r == 0){		errno = ENOTSOCK;		return -1;	} 	switch(r->domain){	case PF_INET:		switch(r->stype){		case SOCK_DGRAM:			net = "udp";			break;		case SOCK_STREAM:			net = "tcp";			break;		default:			net = "gok";			break;		} 		/* get control file name from listener process */		n = read(fd, name, sizeof(name)-1);		if(n <= 0){			_syserrno();			return -1;		}		name[n] = 0;		cfd = open(name, O_RDWR);		if(cfd < 0){			_syserrno();			return -1;		} 		nfd = _sock_data(cfd, net, r->domain, r->stype, r->protocol, &nr);		if(nfd < 0){			_syserrno();			return -1;		} 		if(write(fd, "OK", 2) < 0){			close(nfd);			_syserrno();			return -1;		} 		/* get remote address */		ip = (struct sockaddr_in*)&nr->raddr;		_sock_ingetaddr(nr, ip, &n, "remote");		if(a){			memmove(a, ip, sizeof(struct sockaddr_in));			*alen = sizeof(struct sockaddr_in);		} 		return nfd;	case PF_UNIX:		if(r->other >= 0){			errno = EGREG;			return -1;		} 		for(;;){			/* read path to new connection */			n = read(fd, name, sizeof(name) - 1);			if(n < 0)				return -1;			if(n == 0)				continue;			name[n] = 0; 			/* open new connection */			_sock_srvname(file, name);			nfd = open(file, O_RDWR);			if(nfd < 0)				continue; 			/* confirm opening on new connection */			if(write(nfd, name, strlen(name)) > 0)				break; 			close(nfd);		} 		nr = _sock_newrock(nfd);		if(nr == 0){			close(nfd);			return -1;		}		nr->domain = r->domain;		nr->stype = r->stype;		nr->protocol = r->protocol; 		return nfd;	default:		errno = EOPNOTSUPP;		return -1;	}}