/* date - print or set the date Author: Adri Koppes */ #include "stdio.h" int qflag; int days_per_month[] = { 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 }; char *months[] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" }; char *days[] = { "Thu", "Fri", "Sat", "Sun", "Mon", "Tue", "Wed" }; struct { int year, month, day, hour, min, sec; } tm; long s_p_min; long s_p_hour; long s_p_day; long s_p_year; main(argc, argv) int argc; char **argv; { long t, time(); if (argc > 2) usage(); s_p_min = 60; s_p_hour = 60 * s_p_min; s_p_day = 24 * s_p_hour; s_p_year = 365 * s_p_day; if (argc == 2) { if (*argv[1] == '-' && (argv[1][1] | 0x60) == 'q') { /* Query option. */ char time_buf[15]; qflag = 1; freopen(stdin, "/dev/tty0", "r"); printf("\nPlease enter date (MMDDYYhhmmss). Then hit RETURN.\n"); gets(time_buf); set_time(time_buf); exit(0); } set_time(argv[1]); } else { time(&t); cv_time(t); printf("%s %s %d %02d:%02d:%02d %d\n", days[(t / s_p_day) % 7], months[tm.month], tm.day, tm.hour, tm.min, tm.sec, tm.year); } exit(0); } cv_time(t) long t; { tm.year = 0; tm.month = 0; tm.day = 1; tm.hour = 0; tm.min = 0; tm.sec = 0; while (t >= s_p_year) { if (((tm.year + 2) % 4) == 0) t -= s_p_day; tm.year += 1; t -= s_p_year; } if (((tm.year + 2) % 4) == 0) days_per_month[1]++; tm.year += 1970; while ( t >= (days_per_month[tm.month] * s_p_day)) t -= days_per_month[tm.month++] * s_p_day; while (t >= s_p_day) { t -= s_p_day; tm.day++; } while (t >= s_p_hour) { t -= s_p_hour; tm.hour++; } while (t >= s_p_min) { t -= s_p_min; tm.min++; } tm.sec = (int) t; } set_time(t) char *t; { char *tp; long ct, time(); int len; time(&ct); cv_time(ct); tm.year -= 1970; tm.month++; len = strlen(t); if (len != 12 && len != 10 && len != 6 && len != 4) usage(); tp = t; while (*tp) if (!isdigit(*tp++)) bad(); if (len == 6 || len == 12) tm.sec = conv(&tp, 59); tm.min = conv(&tp, 59); tm.hour = conv(&tp, 23); if (len == 12 || len == 10) { tm.year = conv(&tp, 99); tm.day = conv(&tp, 31); tm.month = conv(&tp, 12); tm.year -= 70; } ct = tm.year * s_p_year; ct += ((tm.year + 1) / 4) * s_p_day; if (((tm.year + 2) % 4) == 0) days_per_month[1]++; len = 0; tm.month--; while (len < tm.month) ct += days_per_month[len++] * s_p_day; ct += --tm.day * s_p_day; ct += tm.hour * s_p_hour; ct += tm.min * s_p_min; ct += tm.sec; if (days_per_month[1] > 28) days_per_month[1] = 28; if (stime(&ct)) { fprintf(stderr, "Set date not allowed\n"); } else { cv_time(ct); } } conv(ptr, max) char **ptr; int max; { int buf; *ptr -=2; buf = atoi(*ptr); **ptr = 0; if (buf < 0 || buf > max) bad(); return(buf); } bad() { fprintf(stderr, "Date: bad conversion\n"); exit(1); } usage() { if (qflag==0) fprintf(stderr, "Usage: date [-q] [[MMDDYY]hhmm[ss]]\n"); exit(1); } isdigit(c) char c; { if (c >= '0' && c <= '9') return(1); else return(0); }