1 /* Set tai offset 2 * by: John Stultz <john.stultz@linaro.org> 3 * (C) Copyright Linaro 2013 4 * Licensed under the GPLv2 5 * 6 * This program is free software: you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation, either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 */ 16 17 18 #include <stdio.h> 19 #include <stdlib.h> 20 #include <time.h> 21 #include <sys/time.h> 22 #include <sys/timex.h> 23 #include <string.h> 24 #include <signal.h> 25 #include <unistd.h> 26 #include "../kselftest.h" 27 28 int set_tai(int offset) 29 { 30 struct timex tx; 31 32 memset(&tx, 0, sizeof(tx)); 33 34 tx.modes = ADJ_TAI; 35 tx.constant = offset; 36 37 return adjtimex(&tx); 38 } 39 40 int get_tai(void) 41 { 42 struct timex tx; 43 44 memset(&tx, 0, sizeof(tx)); 45 46 adjtimex(&tx); 47 return tx.tai; 48 } 49 50 int main(int argc, char **argv) 51 { 52 int i, ret; 53 54 ret = get_tai(); 55 printf("tai offset started at %i\n", ret); 56 57 printf("Checking tai offsets can be properly set: "); 58 for (i = 1; i <= 60; i++) { 59 ret = set_tai(i); 60 ret = get_tai(); 61 if (ret != i) { 62 printf("[FAILED] expected: %i got %i\n", i, ret); 63 return ksft_exit_fail(); 64 } 65 } 66 printf("[OK]\n"); 67 return ksft_exit_pass(); 68 } 69