1 /* $NetBSD: msg.h,v 1.1 2016/12/05 20:10:10 christos Exp $ */ 2 3 /*- 4 * Copyright (c) 2016 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Christos Zoulas. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 struct msg_fds { 33 int pfd[2]; 34 int cfd[2]; 35 }; 36 37 #define CLOSEFD(fd) do { \ 38 if (fd != -1) { \ 39 close(fd); \ 40 fd = -1; \ 41 } \ 42 } while (/*CONSTCOND*/ 0) 43 44 static int 45 msg_open(struct msg_fds *fds) 46 { 47 if (pipe(fds->pfd) == -1) 48 return -1; 49 if (pipe(fds->cfd) == -1) { 50 close(fds->pfd[0]); 51 close(fds->pfd[1]); 52 return -1; 53 } 54 return 0; 55 } 56 57 static void 58 msg_close(struct msg_fds *fds) 59 { 60 CLOSEFD(fds->pfd[0]); 61 CLOSEFD(fds->pfd[1]); 62 CLOSEFD(fds->cfd[0]); 63 CLOSEFD(fds->cfd[1]); 64 } 65 66 static int 67 msg_write_child(const char *info, struct msg_fds *fds, void *msg, size_t len) 68 { 69 ssize_t rv; 70 CLOSEFD(fds->cfd[1]); 71 CLOSEFD(fds->pfd[0]); 72 73 printf("Send %s\n", info); 74 rv = write(fds->pfd[1], msg, len); 75 if (rv != (ssize_t)len) 76 return 1; 77 // printf("Wait %s\n", info); 78 rv = read(fds->cfd[0], msg, len); 79 if (rv != (ssize_t)len) 80 return 1; 81 return 0; 82 } 83 84 static int 85 msg_write_parent(const char *info, struct msg_fds *fds, void *msg, size_t len) 86 { 87 ssize_t rv; 88 CLOSEFD(fds->pfd[1]); 89 CLOSEFD(fds->cfd[0]); 90 91 printf("Send %s\n", info); 92 rv = write(fds->cfd[1], msg, len); 93 if (rv != (ssize_t)len) 94 return 1; 95 // printf("Wait %s\n", info); 96 rv = read(fds->pfd[0], msg, len); 97 if (rv != (ssize_t)len) 98 return 1; 99 return 0; 100 } 101 102 static int 103 msg_read_parent(const char *info, struct msg_fds *fds, void *msg, size_t len) 104 { 105 ssize_t rv; 106 CLOSEFD(fds->pfd[1]); 107 CLOSEFD(fds->cfd[0]); 108 109 printf("Wait %s\n", info); 110 rv = read(fds->pfd[0], msg, len); 111 if (rv != (ssize_t)len) 112 return 1; 113 // printf("Send %s\n", info); 114 rv = write(fds->cfd[1], msg, len); 115 if (rv != (ssize_t)len) 116 return 1; 117 return 0; 118 } 119 120 static int 121 msg_read_child(const char *info, struct msg_fds *fds, void *msg, size_t len) 122 { 123 ssize_t rv; 124 CLOSEFD(fds->cfd[1]); 125 CLOSEFD(fds->pfd[0]); 126 127 printf("Wait %s\n", info); 128 rv = read(fds->cfd[0], msg, len); 129 if (rv != (ssize_t)len) 130 return 1; 131 // printf("Send %s\n", info); 132 rv = write(fds->pfd[1], msg, len); 133 if (rv != (ssize_t)len) 134 return 1; 135 return 0; 136 } 137