fork_exec(struct socket *so, const char *ex, int do_pty) { int s; struct sockaddr_in addr; socklen_t addrlen = sizeof(addr); int opt; const char *argv[256]; /* don't want to clobber the original */ char *bptr; const char *curarg; int c, i, ret; pid_t pid; DEBUG_CALL("fork_exec"); DEBUG_ARG("so = %p", so); DEBUG_ARG("ex = %p", ex); DEBUG_ARG("do_pty = %x", do_pty); if (do_pty == 2) { return 0; } else { addr.sin_family = AF_INET; addr.sin_port = 0; addr.sin_addr.s_addr = INADDR_ANY; if ((s = qemu_socket(AF_INET, SOCK_STREAM, 0)) < 0 || bind(s, (struct sockaddr *)&addr, addrlen) < 0 || listen(s, 1) < 0) { error_report("Error: inet socket: %s", strerror(errno)); closesocket(s); return 0; } } pid = fork(); switch(pid) { case -1: error_report("Error: fork failed: %s", strerror(errno)); close(s); return 0; case 0: setsid(); /* Set the DISPLAY */ getsockname(s, (struct sockaddr *)&addr, &addrlen); close(s); /* * Connect to the socket * XXX If any of these fail, we're in trouble! */ s = qemu_socket(AF_INET, SOCK_STREAM, 0); addr.sin_addr = loopback_addr; do { ret = connect(s, (struct sockaddr *)&addr, addrlen); } while (ret < 0 && errno == EINTR); dup2(s, 0); dup2(s, 1); dup2(s, 2); for (s = getdtablesize() - 1; s >= 3; s--) close(s); i = 0; bptr = g_strdup(ex); /* No need to free() this */ if (do_pty == 1) { /* Setup "slirp.telnetd -x" */ argv[i++] = "slirp.telnetd"; argv[i++] = "-x"; argv[i++] = bptr; } else do { /* Change the string into argv[] */ curarg = bptr; while (*bptr != ' ' && *bptr != (char)0) bptr++; c = *bptr; *bptr++ = (char)0; argv[i++] = g_strdup(curarg); } while (c); argv[i] = NULL; execvp(argv[0], (char **)argv); /* Ooops, failed, let's tell the user why */ fprintf(stderr, "Error: execvp of %s failed: %s\n", argv[0], strerror(errno)); close(0); close(1); close(2); /* XXX */ exit(1); default: qemu_add_child_watch(pid); /* * XXX this could block us... * XXX Should set a timer here, and if accept() doesn't * return after X seconds, declare it a failure * The only reason this will block forever is if socket() * of connect() fail in the child process */ do { so->s = accept(s, (struct sockaddr *)&addr, &addrlen); } while (so->s < 0 && errno == EINTR); closesocket(s); socket_set_fast_reuse(so->s); opt = 1; qemu_setsockopt(so->s, SOL_SOCKET, SO_OOBINLINE, &opt, sizeof(int)); qemu_set_nonblock(so->s); /* Append the telnet options now */ if (so->so_m != NULL && do_pty == 1) { sbappend(so, so->so_m); so->so_m = NULL; } return 1; } }