/**********************************************************************
*  Time comparation  example  for   SQL.RU 
*
************************************************************************/

#include <stdio.h>
#include <time.h>
#include <sys/time.h>
#include <string.h>

struct tm tm_1;  // first time parameter
struct tm tm_2;  // second time parameter
struct timeval s_time; // start time
struct timeval e_time; // end time
time_t l_time1= 0 ;        // first time in a  digit format
time_t l_time2= 0 ;        // second time in a digit format

char cres[ 16 ] ="less then\0";  //character result

int res; // any results

/********************************************************************
*********************************************************************/

int main(int argc, char* argv[])
{

if(argc <  3  )
{
printf ("Invalid number of parameters\n");
return - 1 ;
};

bzero(&tm_1, sizeof(tm));
bzero(&tm_2, sizeof(tm));
bzero(&s_time, sizeof(timeval));
bzero(&e_time, sizeof(timeval));


gettimeofday(&s_time, NULL);  // save start time point

//parsing first parameter
res=sscanf(argv[ 1 ], "%4d-%2d-%2d:%2d:%2d:%2d", 
&tm_1.tm_year, &tm_1.tm_sec,  &tm_1.tm_mon,  &tm_1.tm_mday, &tm_1.tm_hour, &tm_1.tm_min, &tm_1.tm_sec );
if (res !=  6 ) 
{
printf("Invalid format on %s\n Must be a YYYY-MM-DD:HH24:MI:SS \n", argv[ 1 ]);
return - 1 ;
};
tm_1.tm_year=tm_1.tm_year- 1900 ;



//parsing second parameter
res=sscanf(argv[ 2 ], "%4d-%2d-%2d:%2d:%2d:%2d", &tm_2.tm_year, &tm_2.tm_sec,  &tm_2.tm_mon,  &tm_2.tm_mday, &tm_2.tm_hour, &tm_2.tm_min, &tm_2.tm_sec );
if (res !=  6 ) 
{
printf("Invalid format on %s\n Must be a YYYY-MM-DD:HH24:MI:SS \n", argv[ 2 ]);
return - 1 ;
};
tm_2.tm_year=tm_2.tm_year- 1900 ;

l_time1=mktime(&tm_1);
l_time2=mktime(&tm_2);


if(l_time1 > l_time2) sprintf(&cres[ 0 ],  "more then\0");
if(l_time1 == l_time2) sprintf(&cres[ 0 ], "equal to\0");

gettimeofday(&e_time, NULL); // save end time point

printf( "%s %s %s\n", argv[ 1 ], &cres[ 0 ], argv[ 2 ] );
printf ("comparaion takes 0.%.6d second\n", e_time.tv_usec - s_time.tv_usec);

return  0 ;
};