/*++ /* NAME /* unix_pass_listen 3 /* SUMMARY /* start UNIX-domain file descriptor listener /* SYNOPSIS /* #include <listen.h> /* /* int unix_pass_listen(path, backlog, block_mode) /* const char *path; /* int backlog; /* int block_mode; /* /* int unix_pass_accept(fd) /* int fd; /* DESCRIPTION /* This module implements a listener that receives one file descriptor /* across each UNIX-domain connection that is made to it. /* /* unix_pass_listen() creates a listener endpoint with the specified /* permissions, and returns a file descriptor to be used for accepting /* descriptors. /* /* unix_pass_accept() accepts a descriptor. /* /* Arguments: /* .IP path /* Null-terminated string with connection destination. /* .IP backlog /* This argument exists for compatibility and is ignored. /* .IP block_mode /* Either NON_BLOCKING or BLOCKING. This does not affect the /* mode of accepted connections. /* .IP fd /* File descriptor returned by unix_pass_listen(). /* DIAGNOSTICS /* Fatal errors: unix_pass_listen() aborts upon any system call failure. /* unix_pass_accept() leaves all error handling up to the caller. /* LICENSE /* .ad /* .fi /* The Secure Mailer license must be distributed with this software. /* AUTHOR(S) /* Wietse Venema /* IBM T.J. Watson Research /* P.O. Box 704 /* Yorktown Heights, NY 10598, USA /*--*/ /* System library. */ #include <sys_defs.h> #include <sys/socket.h> #include <errno.h> #include <unistd.h> /* Utility library. */ #include <msg.h> #include <sane_accept.h> #include <listen.h> /* unix_pass_accept - accept descriptor */ int unix_pass_accept(int listen_fd) { const char *myname = "unix_pass_accept"; int accept_fd; int recv_fd = -1; accept_fd = sane_accept(listen_fd, (struct sockaddr *) 0, (SOCKADDR_SIZE *) 0); if (accept_fd < 0) { if (errno != EAGAIN) msg_warn("%s: accept connection: %m", myname); return (-1); } else { if (read_wait(accept_fd, 100) < 0) msg_warn("%s: timeout receiving file descriptor: %m", myname); else if ((recv_fd = unix_recv_fd(accept_fd)) < 0) msg_warn("%s: cannot receive file descriptor: %m", myname); if (close(accept_fd) < 0) msg_warn("%s: close: %m", myname); return (recv_fd); } }