/** * sleep-until – Sleeps until a specified time * * Copyright © 2015 Mattias Andrée (maandree@member.fsf.org) * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU Affero General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU Affero General Public License for more details. * * You should have received a copy of the GNU Affero General Public License * along with this program. If not, see . */ #include #include #include int main(int argc, char* argv[]) { char* argv0; char float_part[10]; struct itimerspec value; struct itimerspec largest_value; int i; if (argc < 2) return 0; argv0 = argv[0]; argc--, argv--; memset(&value, 0, sizeof(value)); float_part[9] = '\0'; for (i = 0; i < argc; i++) { char* p1 = argv[i]; char* p2 = strchr(p1, '.'); char excess; size_t len; if (p2) *p2++ = '\0'; value.it_value.tv_sec = (time_t)atoll(p1); if (p2) { len = strlen(p2); memset(float_part, '0', 9 * sizeof(char)); excess = len > 9 ? p2[9] : '0'; len = len > 9 ? 9 : len; memcpy(float_part + 9 - len, p2, len * sizeof(char)); value.it_value.tv_nsec = atol(float_part); if ((excess >= '5') && (value.it_value.tv_nsec++ == 999999999L)) value.it_value.tv_nsec = 0, value.it_value.tv_sec++; } if (i == 0) largest_value = value; else if (value.it_value.tv_sec > largest_value.it_value.tv_sec) largest_value = value; else if (value.it_value.tv_nsec > largest_value.it_value.tv_nsec) largest_value = value; } return 0; }