/* Source: date.c Author: Linda Murphy, murphy@dccs.upenn.edu Date: December 1991 4/29/92 wade@mit.edu Added print_wday() to create a date string in the form "Wed Apr 1 1992". */ #include #include #include #include #include "date.h" #define ASECOND 1 #define AMINUTE 60 #define ANHOUR 3600 #define ADAY 86400 /* 24 x ANHOUR */ #define AMONTH 2419200 /* 28 x ADAY */ #define AYEAR 31536000 /* 365 x ADAY */ #define NUMMONTHS 12 void print_wday(short year, short month, short day, char *result); char *monthnames[] = { "", /* there is no 0th month */ "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" }; int monthlen[] = { 0, /* there is no 0th month */ 31, /* jan */ 29, /* feb */ 31, /* mar */ 30, /* apr */ 31, /* may */ 30, /* jun */ 31, /* jul */ 31, /* aug */ 30, /* sep */ 31, /* oct */ 30, /* nov */ 31 /* dec */ }; /***************************************************************************** * amon to imon - convert ascii string to integer month (0 to 11) * *****************************************************************************/ int atoi_mon (name) char *name; { int i, imon; if (isdigit(*name)) return(atoi(name)); for (imon = -1, i=1; i < 13 && imon<0 ; i++) { if ( strcasecmp(name, monthnames[i]) == 0) imon = i; } return(imon); } /* The delta returned is not precisely correct, it is only an approximate value of the # of seconds between date1 & date2 */ int datecmp (struct daterec date1, struct daterec date2) { int delta; if ( (delta = date1.year - date2.year) != 0) return (delta * AYEAR); if ((delta = date1.month - date2.month) != 0) return (delta * AMONTH); if ((delta = date1.day - date2.day) != 0) return (delta * ADAY); if ((delta = date1.hour - date2.hour) != 0) return (delta * ANHOUR); if ((delta = date1.minute - date2.minute) != 0) return (delta * AMINUTE); if ((delta = date1.sec - date2.sec) != 0) return (delta * ASECOND); /* if we got this far, the dates are equal */ return 0; } /* parse_logdate: expecting " Jan 1 00:00:00 1990" (Month Day Hour:Min:Sec Year) accepts a number instead of 3 letter monthname. year is optional (current year is default). any # of spaces greater than 0 is accepted (where whitespace is indicated) time_opt parameter is true, then "month day year" is acceptable */ int parse_logdate (char *datestr, struct daterec *dt, int opt_time) { char *ptr, *ptr2; time_t now; dt->year = dt->month = dt->day = dt->hour = dt->minute = dt->sec = 0; for (ptr = datestr; *ptr == ' '; ptr++); /* skip blanks */ for (ptr2=ptr; *ptr2 && *ptr2 != ' '; ptr2++); /* find end of month str*/ if (*ptr2 == ' ') { *ptr2 = '\0'; ptr2++; } if ((dt->month = atoi_mon(ptr)) < 1) return 0; ptr = ptr2; /* move past month */ for (; *ptr == ' '; ptr++); /* skip blanks */ if ((dt->day = atoi (ptr)) <= 0) return 0; for (; *ptr && *ptr != ' '; ptr++); /* move past day */ for (; *ptr == ' '; ptr++); /* skip blanks */ for (ptr2 = ptr; *ptr2 && *ptr2 != ':'; ptr2++); /*if there's :, move to it*/ if (*ptr2 != ':' && !opt_time) /* time is not optional */ return 0; if (*ptr2 == ':') { *ptr2 = '\0'; dt->hour = atoi(ptr); ptr = ptr2+1; dt->minute = atoi(ptr); for (; *ptr && *ptr != ':' && *ptr != ' '; ptr++); /* move past minute */ if (*ptr != ':' && !opt_time) /* seconds are not optional */ return 0; if (*ptr == ':') { /* seconds are optional, so look for colon */ ptr++; dt->sec = atoi(ptr); for (; *ptr && *ptr != ' '; ptr++); /* move past second */ } } for (; *ptr == ' '; ptr++); /* skip blanks */ if (!isdigit(*ptr)) { now = time(0); dt->year = atoi(ctime(&now)+20); /* default year is current one */ return 1; } if ((dt->year = atoi(ptr)) < 1) return 0; return 1; } sprintdate(struct daterec date, char *datestr, int fmt) { switch(fmt) { case 1: sprintf(datestr, "%02d/%02d/%d %02d:%02d:%02d", date.month, date.day, date.year, date.hour, date.minute, date.sec); break; case 2: sprintf(datestr, "%d/%02d/%02d %02d:%02d:%02d", date.year, date.month, date.day, date.hour, date.minute, date.sec); break; case 3: sprintf(datestr, "%s %2d %d", monthnames[date.month], date.day, date.year); break; case 4: print_wday(date.year, date.month, date.day, datestr); break; case 0: default: sprintf(datestr, "%s %2d %02d:%02d:%02d %d", monthnames[date.month], date.day, date.hour, date.minute, date.sec, date.year); break; } } int leapyear (y) int y; { if ( (y % 400 == 0) || ( (y % 4 == 0) && (y % 100 != 0) ) ) { return(1); } else return(0); } dateincre (struct daterec *dat, char incrementch) { int daysinmonth; switch (incrementch) { case 'H': if (dat->hour < 23) { (dat->hour)++; break; /* break out of switch */ } dat->hour = 0; /* if hour was 23:, next hour is 00: */ /* continue to next case to incre day */ case 'W': case 'D': dat->day += (incrementch == 'W') ? 7 : 1; if (dat->month == 2) daysinmonth = leapyear(dat->year) ? 29 : 28; else daysinmonth = monthlen[dat->month]; if (dat->day <= daysinmonth) break; /* break out of switch */ /* past the end of the month: fix the day, and incr month */ dat->day -= daysinmonth; /* contine to next case to increment month */ case 'M': if (dat->month < 12) { (dat->month)++; break; /* break out of switch */ } /* if month is December, next month is January, and year increases */ dat->month = 1; /* continue to next case to incre year */ case 'Y': (dat->year)++; break; default: fprintf(stderr,"Increment character must be one of HDWMY\n"); exit (-1); break; } } datedecr (struct daterec *dat, char decrementch) { int daysinmonth; switch (decrementch) { case 'H': if (dat->hour > 0) { (dat->hour)--; break; /* break out of switch */ } dat->hour = 23; /* if hour was 00:, prev hour is 23: */ /* continue to next case to decre day */ case 'W': case 'D': dat->day -= (decrementch == 'W') ? 7 : 1; if (dat->day > 0) break; /* break out of switch */ /* day is <= 0, so we need to fix day, and decre month */ /* how many days are in the previous month? */ if (dat->month == 3) /* previous month was Feb */ daysinmonth = leapyear(dat->year) ? 29 : 28; else if (dat->month <= 1) /* previous month was Dec */ daysinmonth = monthlen[12]; else daysinmonth = monthlen[(dat->month - 1)]; /* since day is 0 or less, adding is really subtracting */ dat->day += daysinmonth; /* contine to next case to decre month */ case 'M': if (dat->month > 1) { (dat->month)--; break; /* break out of switch */ } /* if month is January, prev month is December, and year decreases */ dat->month = 12; /* continue to next case to decre year */ case 'Y': (dat->year)--; break; default: fprintf(stderr,"Decrement character must be one of HDWMY\n"); exit (-1); break; } } setdaterec (struct daterec *dt, time_t tim) { char *timestr; time_t thetime; thetime = tim; timestr = ctime (&thetime); dt->year = atoi(timestr+20); *(timestr+7) = '\0'; dt->month = atoi_mon (timestr+4); dt->day = atoi(timestr+8); dt->hour = atoi(timestr+11); dt->minute = atoi(timestr+14); dt->sec = atoi(timestr+17); } datecpy (struct daterec *d1, struct daterec d2) /* copy d2 into d1 */ { d1->year = d2.year; d1->month = d2.month; d1->day = d2.day; d1->hour = d2.hour; d1->minute = d2.minute; d1->sec = d2.sec; } void print_wday(short year, short month, short day, char *datestr) { struct tm tm; short jan01; short ctr; short days; char *helpptr; short known_yr; char *astr; /* complete tm struct */ tm.tm_sec = 0; tm.tm_min = 0; tm.tm_hour = 0; tm.tm_mday = day; tm.tm_mon = month - 1; tm.tm_year = year - 1900; tm.tm_yday = 0; /* determine day the year starts on - watch out for leap years */ for (known_yr=90,jan01=1; known_yr < tm.tm_year; known_yr++) { if (leapyear(known_yr)) jan01 = (jan01 + (366 % 7)) % 7; else jan01 = (jan01 + (365 % 7)) % 7; } /* correct Febuary days if it is a leap year*/ (leapyear(year)) ? (monthlen[2] = 29) : (monthlen[2] = 28); /* get day of the week 0:6 based on year offset */ for (ctr = 1,days = 0; ctr <= tm.tm_mon; ctr++) days = days + monthlen[ctr]; tm.tm_wday = ((((days + tm.tm_mday) % 7) + jan01 - 1) % 7); /* rip out eol terminator and time */ astr = asctime(&tm); astr[strlen(astr)-1] = '\0'; helpptr = (char *)index(astr,':'); *(helpptr-2) = '\0'; helpptr = helpptr + 7; strcat(astr,helpptr); strcpy(datestr,astr); }