datetime.c File Reference

Data and time processing functions. More...

#include "tpcclibConfig.h"
#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <string.h>
#include <locale.h>
#include <ctype.h>
#include <unistd.h>
#include <math.h>
#include "tpcextensions.h"

Go to the source code of this file.

Functions
struct tm *	gmtime_r (const time_t *t, struct tm *tm)
	Convert time_t to GMT struct tm.
struct tm *	localtime_r (const time_t *t, struct tm *tm)
	Convert time_t to local time in struct tm.
time_t	timegm (struct tm *tm)
	Inverse of gmtime, converting struct tm to time_t.
char *	ctime_r_int (const time_t *t, char *buf)
	Convert calendar time t into a null-terminated string of the form YYYY-MM-DD hh:mm:ss, with length of 19 characters and the null.
int	strDateValid (const char *str)
int	strDateValid2 (const char *str, char *intdate)
int	strDateValid3 (const char *str, char *intdate)
int	strDateValid4 (int dateint, char *intdate, int *year, int *month, int *day)
int	strTimeValid (const char *str)
int	strDateTimeValid (const char *str, char *intdate)
int	strDateTimeRead (const char *str, struct tm *date)
int	strDateRead (const char *str, struct tm *date)
void	time_to_tm (time_t totalsecs, int offset, struct tm *result)
double	tmDifference (struct tm *tm1, struct tm *tm0)
void	tmAdd (int s, struct tm *d)
double	strDateTimeDifference (const char *dt1, const char *dt0)
int	strDateTimeAdd (int s, char *dt)

Detailed Description

Data and time processing functions.

Todo

Use strptime function, when available, to convert string to struct tm.

Definition in file datetime.c.

Function Documentation

ctime_r_int()

char * ctime_r_int	(	const time_t *	t,
		char *	buf )

Convert calendar time t into a null-terminated string of the form YYYY-MM-DD hh:mm:ss, with length of 19 characters and the null.

This is a replacement of the thread-safe ctime_r function which converts to date and time in English format.

Author

Vesa Oikonen

Returns

Returns pointer to the string, or null in case of an error.

See also

time_to_tm, strDateTimeValid, strDateTimeRead

Parameters

t	Pointer to calendar time ; do not give pointer to int here, like &e7mhdr.scan_start_time
buf	Pointer to string where the date and time will be written. It must be pre-allocated for at least 20 characters.

Definition at line 119 of file datetime.c.

  {
  if(buf==NULL) return(NULL);
  buf[0]=(char)0;
  struct tm tm;
  if(!gmtime_r(t, &tm)) return(NULL);
  if(!strftime(buf, 20, "%Y-%m-%d %H:%M:%S", &tm)) return(NULL);
  return(buf);
}

Referenced by parWriteRES().

gmtime_r()

struct tm * gmtime_r	(	const time_t *	t,
		struct tm *	tm )

Convert time_t to GMT struct tm.

This version of gmtime_r function is here for systems (at least Windows) where it is not defined. Uses gmtime, which is threadsafe in Windows.

See also

localtime_r

Returns

Pointer to struct tm, or null in case of an error.

Parameters

t	Pointer to time_t; do not give pointer to int here, like &e7mhdr.scan_start_time
tm	Pointer to struct tm, to be filled here.

Definition at line 31 of file datetime.c.

  {
  struct tm *ltm=gmtime(t);
  if(ltm==NULL || tm==NULL) return(NULL);
  *tm=*ltm; tm->tm_isdst=-1;
  return tm;
}

Referenced by ctime_r_int(), tacReadGEMS(), and timegm().

localtime_r()

struct tm * localtime_r	(	const time_t *	t,
		struct tm *	tm )

Convert time_t to local time in struct tm.

This version of localtime_r function is here for systems (at least Windows) where it is not defined. Uses localtime, which is threadsafe in Windows.

See also

gmtime_r

Returns

Pointer to struct tm, or null in case of an error.

Parameters

t	Pointer to time_t; do not give pointer to int here, like &e7mhdr.scan_start_time
tm	Pointer to struct tm, to be filled here.

Definition at line 54 of file datetime.c.

  {
  struct tm *ltm=localtime(t);
  if(ltm==NULL || tm==NULL) return(NULL);
  *tm=*ltm; tm->tm_isdst=-1;
  return tm;
}

Referenced by tacReadScanditronics().

strDateRead()

int strDateRead	(	const char *	str,
		struct tm *	date )

Reads date from a standard string representation of date.

Returns

0 when successful, <>0 in case of an error.

See also

strDateTimeRead, strDateTimeValid, ctime_r_int

Author

Vesa Oikonen

Parameters

str	Pointer to string that contains date in one of the formats YYYY-MM-DD, DD/MM/YYYY, DD.MM.YYYY, DD/MM/YY, or DD.MM.YYYY.
date	Pointer to allocated struct tm where the date is written; undefined if date is not valid.

Definition at line 378 of file datetime.c.

  {
  char buf[32];
  int ret, n, YYYY=0, MM=0, DD=0;
 
  if(strnlen(str, 10)<8) return 1;
  if((ret=strDateValid(str))<=0) {
    strlcpy(buf, str, 11); 
  } else {
    ret=strDateValid2(str, buf);
    if(ret>0) ret=strDateValid3(str, buf);
  }
  if(ret>0) return 2;
  n=sscanf(buf, "%d-%d-%d", &YYYY, &MM, &DD);
  if(n!=3) return(3);
  date->tm_year=YYYY-1900; date->tm_mday=DD; date->tm_mon=MM-1;
  date->tm_hour=0; date->tm_min=0; date->tm_sec=0; date->tm_isdst=-1;
  ret=strftime(buf, 32, "%Y-%m-%d %H:%M:%S", date);
  if(ret==0) return(4);
  return(0);
}

Referenced by tacReadGEMS(), and tacReadScanditronics().

strDateTimeAdd()

int strDateTimeAdd	(	int	s,
		char *	dt )

Add given time in seconds to the date and time.

Returns

0 if successful.

See also

tmAdd, tmDifference, time_to_tm, strDateTimeDifference

Parameters

s	Time to add in seconds; can be negative.
dt	Pointer to date and time string, edited here. It must be allocated for at least 20 characters.

Definition at line 537 of file datetime.c.

  {
  if(dt==NULL) return(1);
  struct tm tm0;
  if(strDateTimeRead(dt, &tm0)) return(1);
  if(s==0) return(0);
  tmAdd(s, &tm0);
  if(!strftime(dt, 20, "%Y-%m-%d %H:%M:%S", &tm0)) return(2);
  return(0);
}

strDateTimeDifference()

double strDateTimeDifference	(	const char *	dt1,
		const char *	dt0 )

Calculate the difference in seconds between two dates and times in international date and time string format (YYYY-MM-DD hh:mm:ss).

See also

tmDifference, strDateTimeAdd, strDateTimeRead, strDateTimeValid, ctime_r_int

Returns

Returns dt1-dt0 time difference in seconds.

Parameters

dt1	Pointer to date and time string.
dt0	Pointer to date and time string.

Definition at line 519 of file datetime.c.

  {
  if(dt1==NULL || dt0==NULL) return(0.0);
  struct tm tm1, tm0;
  if(strDateTimeRead(dt1, &tm1) || strDateTimeRead(dt0, &tm0)) return(0.0);
  return(tmDifference(&tm1, &tm0));
}

Referenced by dcmMListRead(), and imgReadDICOM().

strDateTimeRead()

int strDateTimeRead	(	const char *	str,
		struct tm *	date )

Reads time and date from a standard string representation of date and time.

Returns

0 when successful, <>0 in case of an error.

See also

strDateRead, strDateTimeValid, ctime_r_int, tmDifference, strClean

Author

Vesa Oikonen

Parameters

str	Pointer to string that contains date and time in one of the formats YYYY-MM-DD hh:mm:ss, DD.MM.YYYY hh:mm:ss, or DD/MM/YY hh:mm:ss
date	Pointer to allocated struct tm where date and time is written. undefined if date or time is not valid.

Definition at line 350 of file datetime.c.

  {
  char buf[32];
  int ret, n, YYYY=0, MM=0, DD=0, hh=0, mm=0, ss=0;
 
  ret=strDateTimeValid(str, buf); if(ret!=0) return(ret);
  n=sscanf(buf, "%d-%d-%d %d:%d:%d", &YYYY, &MM, &DD, &hh, &mm, &ss);
  if(n!=6) return(40);
  date->tm_year=YYYY-1900; date->tm_mday=DD; date->tm_mon=MM-1;
  date->tm_hour=hh; date->tm_min=mm; date->tm_sec=ss; date->tm_isdst=-1;
  ret=strftime(buf, 32, "%Y-%m-%d %H:%M:%S", date);
  if(ret==0) return(50);
  return(0);
}

Referenced by abssWrite(), strDateTimeAdd(), strDateTimeDifference(), tacReadAllogg(), tacReadGEMS(), and tacReadScanditronics().

strDateTimeValid()

int strDateTimeValid	(	const char *	str,
		char *	intdate )

Verify that specified string contains date and time in correct format (YYYY-MM-DD hh:mm:ss, DD.MM.YYYY hh:mm:ss, D.M.YYYY hh:mm:ss, DD.MM.YY hh:mm:ss, or D.M.YY hh:mm:ss). String must start with date, but any contents after time is ignored.

Returns

0 if date and time are in correct format, <0 if format is correct but date or time is invalid, and otherwise >0.

Author

Vesa Oikonen

See also

strDateTimeRead, strTimeValid, strDateValid, strClean

Parameters

str	String to be verified.
intdate	Pointer to preallocated string where date and time is written in international format (YYYY-MM-DD hh:mm:ss); enter NULL, if not needed. Undefined, if date is not valid.

Definition at line 308 of file datetime.c.

  {
  int ret1, ret2, len;
  char correct_date[20], *time_ptr=NULL, tmp[20];
 
  if(str==NULL) return 1;
  // 1/1/70 00:00:00 or 1970-01-01 00:00:00
  if(strnlen(str, 19)<15) return 1;
  /* Separate date and time */
  len=strcspn(str, " \t");
  if(len<6 || len>10) return 1;
  strlcpy(tmp, str, len+1); time_ptr=(char*)str+len+1;
  /* and check the date */
  correct_date[0]=(char)0;
  if((ret1=strDateValid(tmp))<=0) {strlcpy(correct_date, tmp, 20);}
  else if((ret1=strDateValid2(tmp, correct_date))<=0) {}
  else if((ret1=strDateValid3(tmp, correct_date))<=0) {}
  else {return 2;}
 
  /* the check the time */
  ret2=strTimeValid(time_ptr);
  if(ret1>0) {if(ret2>=0) return(100*ret1+ret2); else return(100*ret2);}
  if(ret2>0) return(10*ret2);
  if(ret1<0) {if(ret2<0) return(-3); else return(-1);}
  if(ret2<0) return(-2);
  if(intdate!=NULL) sprintf(intdate, "%10.10s %8.8s", correct_date, time_ptr);
  return 0;
}

Referenced by dcmDT2intl(), strDateTimeRead(), tacReadOldAllogg(), and tacReadSIF().

strDateValid()

int strDateValid

(

const char *

str

)

Verify that specified string contains date in correct international format (YYYY-MM-DD). String must start with date, but any contents after it is ignored.

Returns

0 if date is in correct format, -1 if format is correct but date is invalid, and otherwise >0.

Author

Vesa Oikonen

See also

ctime_r_int, strDateValid2, strDateValid3, strDateValid4, strDateTimeValid, strClean

Parameters

str	String to be verified.

Definition at line 155 of file datetime.c.

  {
  if(str==NULL || strnlen(str, 10)<10) return 1;
  if(str[4]!='-' || str[7]!='-') return 2;
  if(strncasecmp(str, "YYYY-MM-DD", 10)==0) return -1;
  int Y, M, D, n;
  n=sscanf(str, "%4d-%2d-%2d", &Y, &M, &D); if(n!=3) return 3;
  if(M>12 || D>31) return -1;
  if(Y<0 || M<1 || D<1) return -1;
  return 0;
}

Referenced by dcmDA2intl(), strDateRead(), and strDateTimeValid().

strDateValid2()

int strDateValid2	(	const char *	str,
		char *	intdate )

Verify that specified string contains date in correct format (DD.MM.YYYY, D.M.YYYY, DD/MM/YYYY, or D/M/YYYY). String must start with date, but any contents after it is ignored.

Returns

0 if date is in correct format, -1 if format is correct but date is invalid, and otherwise >0.

Author

Vesa Oikonen

See also

ctime_r_int, strDateValid, strDateValid3, strDateValid4, strDateTimeValid

Parameters

str	String to be verified.
intdate	Pointer to preallocated string where date is written in international format; enter NULL, if not needed. Undefined, if date is not valid.

Definition at line 179 of file datetime.c.

  {
  if(str==NULL || strnlen(str, 10)<8) return 1;
  int n; char *cptr;
  cptr=(char*)str; n=strcspn(cptr, "./"); if(n<1 || n>2) return 2;
  cptr+=n+1; n=strcspn(cptr, "./"); if(n<1 || n>2) return 2;
  cptr+=n+1; n=strcspn(cptr, "./- \t\n\r"); if(n!=4) return 2;
  if(strncasecmp(str, "DD.MM.YYYY", 10)==0 || strncasecmp(str, "DD/MM/YYYY", 10)==0) {
    return -1;
  }
  int Y, M, D;
  n=sscanf(str, "%d/%d/%4d", &D, &M, &Y);
  if(n<3) n=sscanf(str, "%d.%d.%4d", &D, &M, &Y);
  if(n!=3) return 3;
  if(M>12 || D>31) return -1;
  if(Y<0 || M<1 || D<1) return -1;
  if(intdate!=NULL) sprintf(intdate, "%04d-%02d-%02d", Y, M, D);
  return 0;
}

Referenced by strDateRead(), and strDateTimeValid().

strDateValid3()

int strDateValid3	(	const char *	str,
		char *	intdate )

Verify that specified string contains date in correct format (DD.MM.YY, D.M.YY, DD/MM/YY, or D/M/YY). String must start with date, but any contents after it is ignored.

Returns

0 if date is in correct format, -1 if format is correct but date is invalid, and otherwise >0.

Author

Vesa Oikonen

See also

ctime_r_int, strDateValid2, strDateValid, strDateValid4, strDateTimeValid

Parameters

str	String to be verified.
intdate	Pointer to allocated string where date is written in international format; enter NULL, if not needed. Undefined, if date is not valid.

Definition at line 214 of file datetime.c.

  {
  if(str==NULL || strnlen(str, 8)<6) return 1;
  int n; char *cptr;
  cptr=(char*)str; n=strcspn(cptr, "./"); if(n<1 || n>2) return 2;
  cptr+=n+1; n=strcspn(cptr, "./"); if(n<1 || n>2) return 2;
  cptr+=n+1; n=strcspn(cptr, "./- \t\n\r"); if(n!=2) return 2;
  if(strncasecmp(str, "DD.MM.YY", 8)==0 || strncasecmp(str, "DD/MM/YY", 8)==0) {
    return -1;
  }
  int Y, M, D;
  n=sscanf(str, "%d/%d/%2d", &D, &M, &Y);
  if(n<3) n=sscanf(str, "%d.%d.%2d", &D, &M, &Y);
  if(n!=3) return 3;
  if(Y>99 || M>12 || D>31) return -1;
  if(Y<0 || M<1 || D<1) return -1;
  if(intdate!=NULL) {
    if(Y>=70) Y+=1900; else Y+=2000;
    sprintf(intdate, "%04d-%02d-%02d", Y, M, D);
  }
  return 0;
}

Referenced by strDateRead(), and strDateTimeValid().

strDateValid4()

int strDateValid4	(	int	dateint,
		char *	intdate,
		int *	year,
		int *	month,
		int *	day )

Verify that specified integer contains date in format YYYYMMDD.

Returns

0 if date is in correct format, -1 if format is correct but date is invalid, and otherwise >0.

Author

Vesa Oikonen

See also

ctime_r_int, strDateValid2, strDateValid3, strDateValid, strDateTimeValid

Parameters

dateint	Integer to be checked; not changed in this routine.
intdate	Pointer to allocated string where date is written in international format; enter NULL, if not needed. Undefined, if date is not valid.
year	Year is written in this pointer; enter NULL if not needed.
month	Month is written in this pointer; enter NULL if not needed.
day	Day is written in this pointer; enter NULL if not needed.

Definition at line 250 of file datetime.c.

  {
  if(dateint<18000101 || dateint>99991231) return 1;
  int Y, M, D, n;
  n=dateint/100; D=dateint-100*n; Y=n/100; M=n-100*Y;
  if(M>12 || D>31) return -1;
  if(Y<1 || M<1 || D<1) return -1;
  if(year!=NULL) *year=Y;
  if(month!=NULL) *month=M;
  if(day!=NULL) *day=D;
  if(intdate!=NULL) {sprintf(intdate, "%04d-%02d-%02d", Y, M, D);}
  return 0;
}

strTimeValid()

int strTimeValid

(

const char *

str

)

Verify that specified string contains time in correct format (hh:mm:ss). String must start with time, but any contents after it is ignored.

Returns

0 if time is in correct format, -1 if format is correct but time is invalid, and otherwise >0.

Author

Vesa Oikonen

See also

strDateTimeRead, strDateTimeValid, strDateValid

Parameters

str	String to be verified.

Definition at line 284 of file datetime.c.

  {
  if(str==NULL || strnlen(str, 8)<8) return 1;
  if(str[2]!=':' || str[5]!=':') return 2;
  if(strncasecmp(str, "hh:mm:ss", 8)==0) return -1;
  int h, m, s, n;
  n=sscanf(str, "%d:%d:%d", &h, &m, &s); if(n!=3) return 3;
  if(h<0 || h>23 || m<0 || m>59 || s<0 || s>59) return -1;
  return 0;
}

Referenced by dcmTM2intl(), iftPutFromString(), and strDateTimeValid().

time_to_tm()

void time_to_tm	(	time_t	totalsecs,
		int	offset,
		struct tm *	result )

Convert calendar time to local broken-down time.

This function is copied from GNU C Library with tiny modifications.

See also

ctime_r_int, tmDifference, tmAdd

Parameters

totalsecs	number of seconds elapsed since 00:00:00 on January 1, 1970, UTC; can be negative to represent times before 1970.
offset	offset seconds adding to totalsecs (e.g. -timezone).
result	pointer to struct tm variable to receive broken-down time.

Definition at line 443 of file datetime.c.

  {
  long int days, rem, y, yg;
  const unsigned short *ip;
 
  days=totalsecs/86400; rem=totalsecs%86400; rem+=offset;
  while(rem<0) {rem+=86400; --days;}
  while(rem>=86400) {rem-=86400; ++days;}
  result->tm_hour=rem/3600;
  rem%=3600; result->tm_min=rem/60;
  result->tm_sec=rem%60;
 
  /* January 1, 1970 was a Thursday. */
  result->tm_wday=(4+days)%7;
  if(result->tm_wday<0) result->tm_wday+=7;
  y=1970;
  while(days<0 || days>=(isleapyear(y)?366:365)) {
    /* Guess a corrected year, assuming 365 days per year. */
    yg=y+math_div(days, 365);
    /* Adjust days and y to match the guessed year. */
    days-=(yg-y)*365 + leaps_between(y, yg);
    y=yg;
  }
  result->tm_year=y-1900; result->tm_yday=days;
  ip=__mon_yday[isleapyear(y)];
  for(y=11; days<ip[y]; y--) continue;
  days-=ip[y]; result->tm_mon=y; result->tm_mday=days+1;
  result->tm_isdst=-1;
}

timegm()

time_t timegm

(

struct tm *

tm

)

Inverse of gmtime, converting struct tm to time_t.

Otherwise same as mktime, except that mktime uses local time. Uses gmtime_r or gmtime_s, if available, otherwise gmtime, which is thread-safe in Windows.

See also

gmtime_r, localtime_r

Returns

Returns the time_t, or -1 in case of an error.

Parameters

tm	Pointer to struct tm.

Definition at line 77 of file datetime.c.

  {
#ifdef HAVE_GMTIME_R
  {
  time_t temp_lt;
  struct tm temp_gm;
  if(!tm) temp_lt=0; else temp_lt=mktime(tm);
  if(gmtime_r(&temp_lt, &temp_gm)==NULL) return((time_t)-1);
  return(time_t)(temp_lt + (temp_lt - mktime(&temp_gm)));
  }
#endif
 
#ifdef HAVE_GMTIME_S
  {
  time_t temp_lt;
  struct tm temp_gm;
  if(!tm) temp_lt=0; else temp_lt=mktime(tm);
  if(gmtime_s(&temp_gm, &temp_lt)!=0) return(time_t)-1);
  return(time_t)(temp_lt + (temp_lt - mktime(&temp_gm)));
  }
#endif
 
  time_t temp_lt;
  struct tm *temp_gm;
  if(!tm) temp_lt=0; else {tm->tm_isdst=-1; temp_lt=mktime(tm);}
  temp_gm=gmtime(&temp_lt); if(temp_gm) temp_gm->tm_isdst=-1;
  return(time_t)(temp_lt + (temp_lt - mktime(temp_gm)));
}

Referenced by tmAdd().

tmAdd()

void tmAdd	(	int	s,
		struct tm *	d )

Add given time in seconds to the date and time.

See also

tmDifference, time_to_tm, strDateTimeAdd, strDateTimeDifference

Parameters

s	Time to add in seconds; can be negative.
d	Pointer to tm structure.

Definition at line 500 of file datetime.c.

  {
  if(d==NULL) return;
  d->tm_sec+=s; 
  //mktime(d); // this automatically normalizes sec to hours etc if necessary
  timegm(d); // this automatically normalizes sec to hours etc if necessary
}

Referenced by abssWrite(), and strDateTimeAdd().

tmDifference()

double tmDifference	(	struct tm *	tm1,
		struct tm *	tm0 )

Calculate the difference in seconds between two given dates and times.

See also

strDateTimeDifference, tmAdd, time_to_tm

Returns

Returns tm1-tm0 in seconds.

Parameters

tm1	Pointer to tm structure.
tm0	Pointer to tm structure.

Definition at line 486 of file datetime.c.

  {
  return(difftime(mktime(tm1), mktime(tm0)));
}

Referenced by strDateTimeDifference().