www.pudn.com > system.rar > bsearch.c

/****************************************************************************/ 
/*  bsearch v2.54                                                           */ 
/*  Copyright (c) 1993-2004  Texas Instruments Incorporated                 */ 
/****************************************************************************/ 
#include  
 
_CODE_ACCESS void *bsearch( 
	      register const void *key,     /* ITEM TO SEARCH FOR           */ 
              register const void *base,    /* POINTER TO ARRAY OF ELEMENTS */ 
              size_t nmemb,                 /* NUMBER OF ELEMENTS TO SORT   */ 
              size_t size,                  /* SIZE IN BYTES OF EACH ITEM   */ 
              int (*compar)(const void *,const void *)) /* COMPARE FUNCTION */ 
 
{ 
   register int i       = 0;             /* left scan index  */ 
   register int j       = nmemb - 1;     /* right scan index */ 
 
   while( i <= j ) 
   { 
      register int pivot = (j + i) / 2;             
      int result = (*compar) (key, (char *)base + (pivot * size)); 
      if (result == 0) return((char *)base + (pivot * size)); 
      if (result < 0) j = pivot - 1; 
		 else i = pivot + 1; 
   } 
 
   return ((void *)0);   /* IF WE GET TO HERE, WE FAILED */ 
}