Formatting Dates

[darfader]

Hi,

I have to alter the format of a date in a string and have written this...

char process_date(FILE ** p_fp, char c)
{
char format[11];
int index = 0;

      /* grab each character from the field */
      if(c != ';')
      {
         index = 0;
         *(format) = NULL;
         while((c != ' '))
         {
            format[index] = c;
            index++;
            c = getc(p_fp[OUT_FILE]);
         }

         /* nullify the string */
         *(format + index) = NULL;

         /* there are four types of date that can be received
          * in the input files
          * 1/1/2003 00:00:00
          * 1/11/2003 00:00:00
          * 11/1/2003 00:00:00
          * 11/11/2003 00:00:00
          * and the finished item should look like this
          * 11/11/2003
          * this is dealt with as follows
          */
         if(format[1] == '/')
         {
            putc('0', p_fp[FIN_FILE]);
            putc(format[0], p_fp[FIN_FILE]);
            putc(format[1], p_fp[FIN_FILE]);

            if(format[3] == '/')
            {
               putc('0', p_fp[FIN_FILE]);
               putc(format[2], p_fp[FIN_FILE]);
               putc(format[3], p_fp[FIN_FILE]);
               putc(format[4], p_fp[FIN_FILE]);
               putc(format[5], p_fp[FIN_FILE]);
               putc(format[6], p_fp[FIN_FILE]);
               putc(format[7], p_fp[FIN_FILE]);
            }
            else
            {
               putc(format[2], p_fp[FIN_FILE]);
               putc(format[3], p_fp[FIN_FILE]);
               putc(format[4], p_fp[FIN_FILE]);
               putc(format[5], p_fp[FIN_FILE]);
               putc(format[6], p_fp[FIN_FILE]);
               putc(format[7], p_fp[FIN_FILE]);
               putc(format[8], p_fp[FIN_FILE]);
            }
         }
         else if(format[2] == '/' && format[4] == '/')
         {
            putc(format[0], p_fp[FIN_FILE]);
            putc(format[1], p_fp[FIN_FILE]);
            putc(format[2], p_fp[FIN_FILE]);
            putc('0', p_fp[FIN_FILE]);
            putc(format[3], p_fp[FIN_FILE]);
            putc(format[4], p_fp[FIN_FILE]);
            putc(format[5], p_fp[FIN_FILE]);
            putc(format[6], p_fp[FIN_FILE]);
            putc(format[7], p_fp[FIN_FILE]);
            putc(format[8], p_fp[FIN_FILE]);
         }
         else
         {
            putc(format[0], p_fp[FIN_FILE]);
            putc(format[1], p_fp[FIN_FILE]);
            putc(format[2], p_fp[FIN_FILE]);
            putc(format[3], p_fp[FIN_FILE]);
            putc(format[4], p_fp[FIN_FILE]);
            putc(format[5], p_fp[FIN_FILE]);
            putc(format[6], p_fp[FIN_FILE]);
            putc(format[7], p_fp[FIN_FILE]);
            putc(format[8], p_fp[FIN_FILE]);
            putc(format[9], p_fp[FIN_FILE]);
         }

         /* remove the time component */
         c = getc(p_fp[OUT_FILE]);
         c = getc(p_fp[OUT_FILE]);
         c = getc(p_fp[OUT_FILE]);
         c = getc(p_fp[OUT_FILE]);
         c = getc(p_fp[OUT_FILE]);
         c = getc(p_fp[OUT_FILE]);
         c = getc(p_fp[OUT_FILE]);
         c = getc(p_fp[OUT_FILE]);

         /* remove the semi-colon */
         c = getc(p_fp[OUT_FILE]);

         /* put the last character back */
         putc(c, p_fp[FIN_FILE]);
         c = getc(p_fp[OUT_FILE]);
      }
      else /* date is null */
      {
         putc(c, p_fp[FIN_FILE]);
         c = getc(p_fp[OUT_FILE]);
      }
      return(c);
}

it is working without error and reasonably quickly, but I was wondering if you would do it differently,

comments welcome,


tia,

[Hammer]

Can you explain what it's supposed to do, showing some examples of input/output too.

[darfader]

sure



before
<more here>;P;LL;LN;0.00;2.40;;30/9/1998 00:00:00;;;;213.16;<more here>
<more here>;P;LL;LN;0.00;9.60;;17/6/1997 00:00:00;;;;303.29;<more here>
<more here>;P;LL;LN;0.00;9.60;;3/7/1997 00:00:00;;;;213.16;<more here>
<more here>;P;LL;LN;0.00;2.40;;19/10/2000 00:00:00;;;;213.16;<more here>


after
<more here>;P;LL;LN;0.00;2.40;;30/09/1998;;;;213.16;<more here>
<more here>;P;LL;LN;0.00;9.60;;17/06/1997;;;;303.29;<more here>
<more here>;P;LL;LN;0.00;9.60;;03/07/1997;;;;213.16;<more here>
<more here>;P;LL;LN;0.00;2.40;;19/10/2000;;;;213.16;<more here>


the specific delimiter before a date is found and that point is then sent to the function where all the characters (before the next delimiter is found) are grabbed and then sorted

I only found four types of possible date
1/1/2003 00:00:00
1/11/2003 00:00:00
11/1/2003 00:00:00
11/11/2003 00:00:00

[Dave_Sinkula]

>but I was wondering if you would do it differently

I might build a string out of the date/time field, then use sscanf to parse the month, day, year, hour, minute and second from the string. And then [f]printf in the desired format. That is, after the string has been built, doing something similar to this.

char buffer[20];
int month, day, year, hour, minute, second;
/* [Build string] */
if ( sscanf(buffer, "%d/%d/%d %d:%d:%d", &day, &month, &year,
            &hour, &minute, &second) == 6 )
{
   fprintf(stdout, "%02d/%02d/%04d", day, month, year);
}

[darfader]

thanks Dave,

that knocks mine into a cocked hat