1 /* 2 * Check delay injection. 3 * 4 * Copyright (c) 2018 The strace developers. 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. The name of the author may not be used to endorse or promote products 16 * derived from this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28 */ 29 30 #include "tests.h" 31 #include <limits.h> 32 #include <stdio.h> 33 #include <stdint.h> 34 #include <stdlib.h> 35 #include <unistd.h> 36 #include <time.h> 37 #include <sys/time.h> 38 #include <sys/wait.h> 39 #include <asm/unistd.h> 40 41 static int64_t 42 usecs_from_tv(const struct timeval *const tv) 43 { 44 return (int64_t) tv->tv_sec * 1000000 + tv->tv_usec; 45 } 46 47 static int64_t 48 usecs_from_ts(const struct timespec *const ts) 49 { 50 return (int64_t) ts->tv_sec * 1000000 + ts->tv_nsec / 1000; 51 } 52 53 static void 54 check_delay(const struct timeval *const tv0, 55 const struct timespec *const ts, 56 const struct timeval *const tv1, 57 const int nproc, 58 const int64_t delay_enter, 59 const int64_t delay_exit) 60 { 61 const int64_t us0 = usecs_from_tv(tv0); 62 const int64_t us = usecs_from_ts(ts); 63 const int64_t us1 = usecs_from_tv(tv1); 64 65 if (us - us0 < delay_exit * (nproc - 1) / nproc) 66 _exit(1); 67 68 if (us - us0 > delay_exit * (nproc + 1) / nproc) 69 _exit(2); 70 71 if (us1 - us < delay_enter * (nproc - 1) / nproc) 72 _exit(3); 73 74 if (us1 - us > delay_enter * (nproc + 1) / nproc) 75 _exit(4); 76 } 77 78 static void 79 run(const int nproc, const int delay_enter, const int delay_exit) 80 { 81 struct timeval prev = { 0, 0 }, now; 82 83 for (int i = 0; i < nproc; ++i, prev = now) { 84 struct timespec ts; 85 86 if (i && clock_gettime(CLOCK_REALTIME, &ts)) 87 perror_msg_and_fail("clock_gettime"); 88 89 if (syscall(__NR_gettimeofday, &now, NULL)) 90 perror_msg_and_fail("gettimeofday"); 91 92 if (!i) 93 continue; 94 95 check_delay(&prev, &ts, &now, nproc, delay_enter, delay_exit); 96 } 97 98 _exit(0); 99 } 100 101 int 102 main(int ac, char *av[]) 103 { 104 if (ac != 4) 105 error_msg_and_fail("usage: delay <nproc> <delay_enter> <delay_exit>"); 106 107 const int nproc = atoi(av[1]); 108 if (nproc <= 1) 109 perror_msg_and_fail("invalid nproc: %s", av[1]); 110 111 const int delay_enter = atoi(av[2]); 112 if (delay_enter <= 0) 113 perror_msg_and_fail("invalid delay_enter: %s", av[2]); 114 115 const int delay_exit = atoi(av[3]); 116 if (delay_exit <= 0) 117 perror_msg_and_fail("invalid delay_exit: %s", av[3]); 118 119 for (int i = 0; i < nproc; ++i) { 120 pid_t pid = fork(); 121 122 if (pid) 123 usleep(MAX(delay_enter, delay_exit) / nproc); 124 else 125 run(nproc, delay_enter, delay_exit); 126 } 127 128 int status; 129 while (wait(&status) > 0) { 130 if (status) 131 perror_msg_and_fail("wait status %d", status); 132 } 133 134 return 0; 135 } 136
