pipe_reverse_test.c revision 302408
1/* 2Copyright (C) 2004 Michael J. Silbersack. All rights reserved. 3 4Redistribution and use in source and binary forms, with or without 5modification, are permitted provided that the following conditions 6are met: 71. Redistributions of source code must retain the above copyright 8 notice, this list of conditions and the following disclaimer. 92. Redistributions in binary form must reproduce the above copyright 10 notice, this list of conditions and the following disclaimer in the 11 documentation and/or other materials provided with the distribution. 12 13THIS SOFTWARE IS PROVIDED BY AUTHOR AND CONTRIBUTORS ``AS IS'' AND 14ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 15IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 16ARE DISCLAIMED. IN NO EVENT SHALL AUTHOR OR CONTRIBUTORS BE LIABLE 17FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 18DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 19OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 20HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 21LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 22OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 23SUCH DAMAGE. 24*/ 25 26#include <sys/types.h> 27#include <sys/stat.h> 28#include <sys/wait.h> 29#include <assert.h> 30#include <err.h> 31#include <errno.h> 32#include <stdio.h> 33#include <stdlib.h> 34#include <string.h> 35#include <unistd.h> 36 37/* 38 * $FreeBSD: stable/11/tests/sys/kern/pipe/pipe_reverse_test.c 290914 2015-11-16 05:38:40Z ngie $ 39 * This program simply tests writing through the reverse direction of 40 * a pipe. Nothing too fancy, it's only needed because most pipe-using 41 * programs never touch the reverse direction (it doesn't exist on 42 * Linux.) 43 */ 44 45int 46main(void) 47{ 48 char buffer[65535], buffer2[65535], go[] = "go", go2[] = "go2"; 49 int desc[2], ipc_coord[2]; 50 size_t i; 51 ssize_t total; 52 int buggy, error; 53 pid_t new_pid; 54 55 buggy = 0; 56 total = 0; 57 58 error = pipe(desc); 59 if (error == -1) 60 err(1, "Couldn't allocate data pipe"); 61 62 error = pipe(ipc_coord); 63 if (error == -1) 64 err(1, "Couldn't allocate IPC coordination pipe"); 65 66 buffer[0] = 'A'; 67 68 for (i = 1; i < (int)sizeof(buffer); i++) { 69 buffer[i] = buffer[i - 1] + 1; 70 if (buffer[i] > 'Z') 71 buffer[i] = 'A'; 72 } 73 74 new_pid = fork(); 75 assert(new_pid != -1); 76 77#define SYNC_R(i, _buf) do { \ 78 int _error = errno; \ 79 warnx("%d: waiting for synchronization", __LINE__); \ 80 if (read(ipc_coord[i], &_buf, sizeof(_buf)) != sizeof(_buf)) \ 81 err(1, "failed to synchronize (%s)", (i == 0 ? "parent" : "child")); \ 82 errno = _error; \ 83 } while(0) 84 85#define SYNC_W(i, _buf) do { \ 86 int _error = errno; \ 87 warnx("%d: sending synchronization", __LINE__); \ 88 if (write(ipc_coord[i], &_buf, sizeof(_buf)) != sizeof(_buf)) \ 89 err(1, "failed to synchronize (%s)", (i == 0 ? "child" : "parent")); \ 90 errno = _error; \ 91 } while(0) 92 93#define WRITE(s) do { \ 94 ssize_t _size; \ 95 if ((_size = write(desc[1], &buffer[total], s)) != s) \ 96 warn("short write; wrote %zd, expected %d", _size, s); \ 97 total += _size; \ 98 } while(0) 99 100 if (new_pid == 0) { 101 SYNC_R(0, go); 102 for (i = 0; i < 8; i++) 103 WRITE(4096); 104 105 SYNC_W(0, go2); 106 SYNC_R(0, go); 107 108 for (i = 0; i < 2; i++) 109 WRITE(4096); 110 111 SYNC_W(0, go2); 112 113 _exit(0); 114 } 115 116 SYNC_W(1, go); 117 SYNC_R(1, go2); 118 119 error = read(desc[0], &buffer2, 8 * 4096); 120 total += error; 121 printf("Read %d bytes\n", error); 122 123 SYNC_W(1, go); 124 SYNC_R(1, go2); 125 126 error = read(desc[0], &buffer2[total], 2 * 4096); 127 total += error; 128 printf("Read %d bytes, done\n", error); 129 130 if (memcmp(buffer, buffer2, total) != 0) { 131 for (i = 0; i < (size_t)total; i++) { 132 if (buffer[i] != buffer2[i]) { 133 buggy = 1; 134 printf("Location %zu input: %hhx " 135 "output: %hhx\n", 136 i, buffer[i], buffer2[i]); 137 } 138 } 139 } 140 141 waitpid(new_pid, NULL, 0); 142 143 if ((buggy == 1) || (total != 10 * 4096)) 144 errx(1, "FAILED"); 145 else 146 printf("SUCCESS\n"); 147 148 exit(0); 149} 150