dkchcbd.c

roots--一个轻量级的内存数据库系统。基于Hash Map的table设计。快速轻巧。

/*
Copyright (c) 2003, Dan Kranz and Arnold Rom
All rights reserved.

Redistribution and use in source and binary forms, with or
without modification, are permitted provided that the following
conditions are met:

    * Redistributions of source code must retain the above
      copyright notice, this list of conditions and the following
      disclaimer.

    * Redistributions in binary form must reproduce the above
      copyright notice, this list of conditions and the following
      disclaimer in the documentation and/or other materials
      provided with the distribution.

    * The names of its contributors may not be used to endorse or
      promote products derived from this software without specific
      prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/

/* The nf binary integers stored in array are converted to ASCII tokens.
   These are stored in block at the nf fields.

   The entries in field are paired, i.e. field start, field length.
   
   The length parameters of the field entries are used to control
   conversion as follows:

      field length = 0     The number is ignored.

      field length > 0     The number is converted and stored.
                           The output field is set to blanks before
                           conversion.  The resulting ASCII number is right
                           justified in the field.  Zero valued numbers are
                           not moved to block.

      field length < 0     Use the absolute value of field length to
                           determine the output field length.  The output
                           field is set to zeros before conversion.  This
                           allows us to produce numbers with leading zeros.
                           Oversized numbers are truncated on the left.
*/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <roots.h>

void chcbd(long *array, void *block, long *fields, long *nf)
{
   char number[80];
   BYTE *bpt;
   long n, field_start, field_length;
   int digits;

   for (n = *nf; n--;) {
      field_start = *fields++;
      field_length = *fields++;

      /* Ignore number if output field length equal zero */
      if (field_length != 0) {

         bpt = (BYTE*) block - 1 + field_start;

         /* Initialize field with leading zeros if field_length < 0  */
         if (field_length < 0) {
            field_length = -field_length;
            memset(bpt,'0', (size_t) field_length);
         }

         /* Otherwise fill field with blanks */
         else memset(bpt,' ', (size_t) field_length);

         /* No conversion if number = zero */
         if (*array != 0) {

            /* Convert to ascii */
            sprintf(number,"%ld", *array);
            digits = strlen(number);

            /* If the number doesn't fit field */
            if (digits > field_length) {

               /* Output field width is greater than zero */
               if (*(fields-1) > 0)
                  memset(bpt,'*', (size_t) field_length);

               /* Truncate digits on left, move remaining digits to block */
               else
                  memcpy(bpt,&number[digits-field_length],digits);
            }
      
            /* Move number to block(field) */
            else {
               bpt += (field_length - digits);
               memcpy(bpt,number,digits);
            }
         }
      }

      /* Next number */
      ++array;
   }
}