/* $NetBSD: msg.h,v 1.3 2020/03/06 14:06:56 kamil Exp $ */ /*- * Copyright (c) 2016 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Christos Zoulas. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. */ struct msg_fds { int pfd[2]; int cfd[2]; }; #define CLOSEFD(fd) do { \ if (fd != -1) { \ close(fd); \ fd = -1; \ } \ } while (/*CONSTCOND*/ 0) static int __used msg_open(struct msg_fds *fds) { if (pipe(fds->pfd) == -1) return -1; if (pipe(fds->cfd) == -1) { close(fds->pfd[0]); close(fds->pfd[1]); return -1; } return 0; } static void __used msg_close(struct msg_fds *fds) { CLOSEFD(fds->pfd[0]); CLOSEFD(fds->pfd[1]); CLOSEFD(fds->cfd[0]); CLOSEFD(fds->cfd[1]); } static int __used msg_write_child(const char *info, struct msg_fds *fds, void *msg, size_t len) { ssize_t rv; CLOSEFD(fds->cfd[1]); CLOSEFD(fds->pfd[0]); // printf("Send %s\n", info); rv = write(fds->pfd[1], msg, len); if (rv != (ssize_t)len) return 1; // printf("Wait %s\n", info); rv = read(fds->cfd[0], msg, len); if (rv != (ssize_t)len) return 1; return 0; } static int __used msg_write_parent(const char *info, struct msg_fds *fds, void *msg, size_t len) { ssize_t rv; CLOSEFD(fds->pfd[1]); CLOSEFD(fds->cfd[0]); // printf("Send %s\n", info); rv = write(fds->cfd[1], msg, len); if (rv != (ssize_t)len) return 1; // printf("Wait %s\n", info); rv = read(fds->pfd[0], msg, len); if (rv != (ssize_t)len) return 1; return 0; } static int __used msg_read_parent(const char *info, struct msg_fds *fds, void *msg, size_t len) { ssize_t rv; CLOSEFD(fds->pfd[1]); CLOSEFD(fds->cfd[0]); // printf("Wait %s\n", info); rv = read(fds->pfd[0], msg, len); if (rv != (ssize_t)len) return 1; // printf("Send %s\n", info); rv = write(fds->cfd[1], msg, len); if (rv != (ssize_t)len) return 1; return 0; } static int __used msg_read_child(const char *info, struct msg_fds *fds, void *msg, size_t len) { ssize_t rv; CLOSEFD(fds->cfd[1]); CLOSEFD(fds->pfd[0]); // printf("Wait %s\n", info); rv = read(fds->cfd[0], msg, len); if (rv != (ssize_t)len) return 1; // printf("Send %s\n", info); rv = write(fds->pfd[1], msg, len); if (rv != (ssize_t)len) return 1; return 0; } #define PARENT_TO_CHILD(info, fds, msg) \ SYSCALL_REQUIRE(msg_write_child(info " to child " # fds, &fds, &msg, \ sizeof(msg)) == 0) #define CHILD_FROM_PARENT(info, fds, msg) \ FORKEE_ASSERT(msg_read_parent(info " from parent " # fds, &fds, &msg, \ sizeof(msg)) == 0) #define CHILD_TO_PARENT(info, fds, msg) \ FORKEE_ASSERT(msg_write_parent(info " to parent " # fds, &fds, &msg, \ sizeof(msg)) == 0) #define PARENT_FROM_CHILD(info, fds, msg) \ SYSCALL_REQUIRE(msg_read_child(info " from parent " # fds, &fds, &msg, \ sizeof(msg)) == 0)