lib/other/lsearch.c

   1 #include <lib.h>
   2 #include <string.h>
   3 /*  lsearch(3)  and  lfind(3)
   4  *
   5  *  Author: Terrence W. Holm          Sep. 1988
   6  */
   7
   8 #include <stddef.h>
   9
  10 _PROTOTYPE( char *lsearch, (char *key, char *base,
  11                             unsigned *count, unsigned width,
  12                             int (*keycmp)(const void *, const void *)));
  13 _PROTOTYPE( char *lfind, (char *key, char *base,
  14                             unsigned *count, unsigned width,
  15                             int (*keycmp)(const void *, const void *)));
  16
  17 char *lsearch(key, base, count, width, keycmp)
  18 char *key;
  19 char *base;
  20 unsigned *count;
  21 unsigned width;
  22 _PROTOTYPE( int (*keycmp), (const void *, const void *));
  23 {
  24   char *entry;
  25   char *last = base + *count * width;
  26
  27   for (entry = base; entry < last; entry += width)
  28         if (keycmp(key, entry) == 0) return(entry);
  29
  30   bcopy(key, last, width);
  31   *count += 1;
  32   return(last);
  33 }
  34
  35
  36 char *lfind(key, base, count, width, keycmp)
  37 char *key;
  38 char *base;
  39 unsigned *count;
  40 unsigned width;
  41 _PROTOTYPE( int (*keycmp), (const void *, const void *));
  42 {
  43   char *entry;
  44   char *last = base + *count * width;
  45
  46   for (entry = base; entry < last; entry += width)
  47         if (keycmp(key, entry) == 0) return(entry);
  48
  49   return((char *)NULL);
  50 }