modules/ma/bitmask.c

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FUNCTIONS

This source file includes following functions.
  1. MA_isset
  2. MA_set
  3. MA_clear
  4. MA_new
  5. MA_prt
  6. MA_and
  7. MA_xor
  8. MA_or
  9. MA_not
  10. MA_bitcount
  11. MA_to_string
  12. main

   1 /***************************************
   2   $Revision: 1.12 $
   3 
   4   bitmask (ma) - bitmask.c - library for manipulating fixed size bitmasks.
   5 
   6   Status: NOT REVUED, TESTED, INCOMPLETE
   7 
   8   Design and implementation by: Marek Bukowy, Chris Ottrey.
   9 
  10   ******************/ /******************
  11   Copyright (c) 1999                              RIPE NCC
  12  
  13   All Rights Reserved
  14   
  15   Permission to use, copy, modify, and distribute this software and its
  16   documentation for any purpose and without fee is hereby granted,
  17   provided that the above copyright notice appear in all copies and that
  18   both that copyright notice and this permission notice appear in
  19   supporting documentation, and that the name of the author not be
  20   used in advertising or publicity pertaining to distribution of the
  21   software without specific, written prior permission.
  22   
  23   THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
  24   ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS; IN NO EVENT SHALL
  25   AUTHOR BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY
  26   DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
  27   AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
  28   OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  29   ***************************************/
  30 
  31 
  32 
  33 #include <stdio.h>
  34 #include <stdarg.h>
  35 #include <stdlib.h>
  36 #include <assert.h>
  37 
  38 #include <string.h>
  39 
  40 #include "bitmask.h"
  41 #include "memwrap.h"
  42 #include "globaldefs.h"
  43 
  44 int MA_isset(mask_t d, unsigned b) {
     /* [<][>][^][v][top][bottom][index][help] */
  45   return( 
  46  (d.data[b / MASK_BITS_BASESIZE] &(1 <<(b % MASK_BITS_BASESIZE)))
  47    > 0);
  48 }
  49 
  50 void MA_set(mask_t *m_ptr, unsigned b, unsigned v) {
     /* [<][>][^][v][top][bottom][index][help] */
  51   assert(b < MASK_MAX);
  52   assert(v == 0 || v == 1);
  53 
  54   if(v == 1)
  55     m_ptr->data[b / MASK_BITS_BASESIZE] |=(1 <<(b % MASK_BITS_BASESIZE));
  56   else
  57     m_ptr->data[b / MASK_BITS_BASESIZE] &= ~(1 <<(b % MASK_BITS_BASESIZE));
  58 }
  59 
  60 void MA_clear(mask_t *m_ptr) {
     /* [<][>][^][v][top][bottom][index][help] */
  61   memset(m_ptr, 0, sizeof(mask_t));
  62 } /* MA_clear() */
  63 
  64 
  65 /* set bits in dptr. variable number of args, terminated by MA_END
  66    
  67    MA_END is -1, so the arguments are of type signed int
  68  */
  69 mask_t MA_new(int n,...) {
     /* [<][>][^][v][top][bottom][index][help] */
  70   va_list         ap;
  71   mask_t d;
  72 
  73   MA_clear(&d);
  74 
  75   /* cover the "empty mask" case => MA_new(MA_END) invoked */
  76   for ( va_start(ap, n); n != MA_END; n = va_arg(ap, int) ) {
  77       MA_set(&d, (unsigned) n, 1);
  78   }
  79   va_end(ap);
  80 
  81   return d;
  82 }
  83 
  84 
  85 void MA_prt(mask_t m) {
     /* [<][>][^][v][top][bottom][index][help] */
  86   unsigned i;
  87 
  88   for (i = 0; i < MASK_MAX; i++) {
  89     printf("%d", MA_isset(m, i));
  90   }
  91 
  92   printf("\n");
  93 
  94   for (i = 0; i < MASK_BITS_WORDS; i++) {
  95     printf("0x%0*X ", 2 * sizeof(MASK_BITS_BASETYPE), m.data[i]);
  96   }
  97 
  98   printf("\n");
  99 }
 100 
 101 /* Perform a logical AND on two masks.
 102    Author: ottrey
 103    Date: Tue Jul  6 13:28:24 CEST 1999
 104    NB: This operation could/should be done a word at a time?
 105 */
 106 mask_t MA_and(mask_t a, mask_t b) {
     /* [<][>][^][v][top][bottom][index][help] */
 107   mask_t c;
 108   unsigned i;
 109 
 110   for (i=0; i < MASK_BITS_WORDS; i++ )  {
 111     c.data[i] = a.data[i] & b.data[i];
 112   }
 113   return c;
 114 } /* MA_and() */
 115 
 116 /* Perform a logical XOR on two masks.
 117    Author: ottrey
 118    Date: Thu Jul  8 14:50:14 CEST 1999
 119    NB: This operation could/should be done a word at a time?
 120 */
 121 mask_t MA_xor(mask_t a, mask_t b) {
     /* [<][>][^][v][top][bottom][index][help] */
 122   mask_t c;
 123   unsigned i;
 124 
 125   for (i=0; i < MASK_BITS_WORDS; i++ )  {
 126     c.data[i] = a.data[i] ^ b.data[i];
 127   }
 128 
 129   return c;
 130 
 131 } /* MA_xor() */
 132 
 133 /* Perform a logical OR on two masks.
 134    Author: ottrey
 135    Date: Thu Jul  8 16:34:34 CEST 1999
 136    NB: This operation could/should be done a word at a time?
 137 */
 138 mask_t MA_or(mask_t a, mask_t b) {
     /* [<][>][^][v][top][bottom][index][help] */
 139   mask_t c;
 140   unsigned  i;
 141 
 142   for (i=0; i < MASK_BITS_WORDS; i++ )  {
 143     c.data[i] = a.data[i] | b.data[i];
 144   }
 145 
 146   return c;
 147 
 148 } /* MA_or() */
 149 
 150 /* Perform a logical NOT operation on a mask.
 151    Author: marek
 152    Date: Fri Jan 14 17:15:00 MET 2000
 153    NB: This operation is done a word at a time.
 154 */
 155 mask_t MA_not(mask_t a) {
     /* [<][>][^][v][top][bottom][index][help] */
 156   mask_t c;
 157   unsigned i;
 158   
 159   for (i=0; i < MASK_BITS_WORDS; i++ )  {
 160     c.data[i] = ~a.data[i];
 161   }
 162   return c;
 163 }
 164 
 165 /* Counts the number of bits set. */
 166 int MA_bitcount(mask_t m) {
     /* [<][>][^][v][top][bottom][index][help] */
 167   unsigned i;
 168   int count=0;
 169 
 170   for (i=0; i < MASK_MAX; i++) {
 171     count += MA_isset(m, i);
 172   }
 173 
 174   return count;
 175 
 176 } /* MA_bitcount() */
 177 
 178 /* Convert the bitmap to a string comprising of tokens from an array of tokens.
 179    Author: ottrey
 180    Date: Tue Jul  6 13:28:24 CEST 1999
 181 */
 182 char *MA_to_string(mask_t mask, char * const *tokens) {
     /* [<][>][^][v][top][bottom][index][help] */
 183   char *str;
 184   char str_buf[STR_L];
 185   int count;
 186   unsigned i;
 187   int length;
 188 
 189   strcpy(str_buf, "");
 190 
 191   count=0;
 192   sprintf(str_buf, "{");
 193   for (i=0;  tokens[i] != NULL; i++) {
 194     if ( MA_isset(mask, i) != 0) {
 195       strcat(str_buf, tokens[i]);
 196       strcat(str_buf, ",");
 197       count++;
 198     }
 199   }
 200   if (count == 0) {
 201     strcat(str_buf, "NULL ");
 202   }
 203   length = strlen(str_buf);
 204   str_buf[length-1] = '}';
 205 
 206   /* str = (char *)calloc(1, strlen(str_buf)+1); */
 207   dieif(wr_calloc( (void **) &str,  1, strlen(str_buf)+1) != UT_OK);
 208 
 209   strcpy(str, str_buf);
 210 
 211   return str;
 212 
 213 } /* MA_to_string() */
 214 
 215 #ifdef MODULE_TEST
 216 void 
 217 main() {
     /* [<][>][^][v][top][bottom][index][help] */
 218   mask_t  d;
 219 
 220   d = MA_new(1, 4, 56, 3, 5, 7, 19, MA_END);
 221 
 222   MA_prt(d);
 223 
 224   MA_set(&d, 3, 0);
 225   MA_set(&d, 7, 0);
 226   MA_set(&d, 9, 0);
 227   MA_set(&d, 19, 0);
 228 
 229   MA_prt(d);
 230 }
 231 #endif

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