Source File ma/bitmask.c

    1    | /***************************************
    2    |   $Revision: 1.15 $
    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) 1999,2000,2001,2002               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 "rip.h"
    34   |
    35   | #include <stdio.h>
    36   | #include <stdarg.h>
    37   | #include <stdlib.h>
    38   | #include <assert.h>
    39   |
    40   | #include <string.h>
    41   |
    42   | int MA_isset(mask_t d, unsigned b) {
    43   |   return(
    44   |  (d.data[b / MASK_BITS_BASESIZE] &(1 <<(b % MASK_BITS_BASESIZE)))
    45   |    > 0);
    46   | }
    47   |
    48   | void MA_set(mask_t *m_ptr, unsigned b, unsigned v) {
    49   |   assert(b < MASK_MAX);
    50   |   assert(v == 0 || v == 1);
    51   |
    52   |   if(v == 1)
    53   |     m_ptr->data[b / MASK_BITS_BASESIZE] |=(1 <<(b % MASK_BITS_BASESIZE));
    54   |   else
    55   |     m_ptr->data[b / MASK_BITS_BASESIZE] &= ~(1 <<(b % MASK_BITS_BASESIZE));
    56   | }
    57   |
    58   | void MA_clear(mask_t *m_ptr) {
    59   |   memset(m_ptr, 0, sizeof(mask_t));
    60   | } /* MA_clear() */
    61   |
    62   |
    63   | /* set bits in dptr. variable number of args, terminated by MA_END
    64   |
    65   |    MA_END is -1, so the arguments are of type signed int
    66   |  */
    67   | mask_t MA_new(int n,...) {
    68   |   va_list         ap;
    69   |   mask_t d;
    70   |
    71   |   MA_clear(&d);
    72   |
    73   |   /* cover the "empty mask" case => MA_new(MA_END) invoked */
    74   |   for ( va_start(ap, n); n != MA_END; n = va_arg(ap, int) ) {
    75   |       MA_set(&d, (unsigned) n, 1);
    76   |   }
    77   |   va_end(ap);
    78   |
    79   |   return d;
    80   | }
    81   |
    82   |
    83   | void MA_prt(mask_t m) {
    84   |   unsigned i;
    85   |
    86   |   for (i = 0; i < MASK_MAX; i++) {
    87   |     printf("%d", MA_isset(m, i));
    88   |   }
    89   |
    90   |   printf("\n");
    91   |
    92   |   for (i = 0; i < MASK_BITS_WORDS; i++) {
    93   |     printf("0x%0*X ", 2 * (int)sizeof(MASK_BITS_BASETYPE), m.data[i]);
    94   |   }
    95   |
    96   |   printf("\n");
    97   | }
    98   |
    99   | /* Perform a logical AND on two masks.
    100  |    Author: ottrey
    101  |    Date: Tue Jul  6 13:28:24 CEST 1999
    102  |    NB: This operation could/should be done a word at a time?
    103  | */
    104  | mask_t MA_and(mask_t a, mask_t b) {
    105  |   mask_t c;
    106  |   unsigned i;
    107  |
    108  |   for (i=0; i < MASK_BITS_WORDS; i++ )  {
    109  |     c.data[i] = a.data[i] & b.data[i];
    110  |   }
    111  |   return c;
    112  | } /* MA_and() */
    113  |
    114  | /* Perform a logical XOR on two masks.
    115  |    Author: ottrey
    116  |    Date: Thu Jul  8 14:50:14 CEST 1999
    117  |    NB: This operation could/should be done a word at a time?
    118  | */
    119  | mask_t MA_xor(mask_t a, mask_t b) {
    120  |   mask_t c;
    121  |   unsigned i;
    122  |
    123  |   for (i=0; i < MASK_BITS_WORDS; i++ )  {
    124  |     c.data[i] = a.data[i] ^ b.data[i];
    125  |   }
    126  |
    127  |   return c;
    128  |
    129  | } /* MA_xor() */
    130  |
    131  | /* Perform a logical OR on two masks.
    132  |    Author: ottrey
    133  |    Date: Thu Jul  8 16:34:34 CEST 1999
    134  |    NB: This operation could/should be done a word at a time?
    135  | */
    136  | mask_t MA_or(mask_t a, mask_t b) {
    137  |   mask_t c;
    138  |   unsigned  i;
    139  |
    140  |   for (i=0; i < MASK_BITS_WORDS; i++ )  {
    141  |     c.data[i] = a.data[i] | b.data[i];
    142  |   }
    143  |
    144  |   return c;
    145  |
    146  | } /* MA_or() */
    147  |
    148  | /* Perform a logical NOT operation on a mask.
    149  |    Author: marek
    150  |    Date: Fri Jan 14 17:15:00 MET 2000
    151  |    NB: This operation is done a word at a time.
    152  | */
    153  | mask_t MA_not(mask_t a) {
    154  |   mask_t c;
    155  |   unsigned i;
    156  |
    157  |   for (i=0; i < MASK_BITS_WORDS; i++ )  {
    158  |     c.data[i] = ~a.data[i];
    159  |   }
    160  |   return c;
    161  | }
    162  |
    163  | /* Counts the number of bits set. */
    164  | int MA_bitcount(mask_t m) {
    165  |   unsigned i;
    166  |   int count=0;
    167  |
    168  |   for (i=0; i < MASK_MAX; i++) {
    169  |     count += MA_isset(m, i);
    170  |   }
    171  |
    172  |   return count;
    173  |
    174  | } /* MA_bitcount() */
    175  |
    176  | /* Convert the bitmap to a string comprising of tokens from an array of tokens.
    177  |    Author: ottrey
    178  |    Date: Tue Jul  6 13:28:24 CEST 1999
    179  | */
    180  | char *MA_to_string(mask_t mask, char * const *tokens) {
    181  |   char str_buf[STR_L];
    182  |   int count;
    183  |   unsigned i;
    184  |   int length;
    185  |
    186  |   count=0;
    187  |   strcpy(str_buf, "{");
    188  |   for (i=0;  tokens[i] != NULL; i++) {
    189  |     if ( MA_isset(mask, i) != 0) {
    190  |       strcat(str_buf, tokens[i]);
    191  |       strcat(str_buf, ",");
    192  |       count++;
    193  |     }
    194  |   }
    195  |   if (count == 0) {
    196  |     strcat(str_buf, "NULL ");
    197  |   }
    198  |   length = strlen(str_buf);
    199  |   str_buf[length-1] = '}';
    200  |
    201  |   return UT_strdup(str_buf);
    202  |
    203  | } /* MA_to_string() */
    204  |
    205  | #ifdef MODULE_TEST
    206  | void
    207  | main() {
    208  |   mask_t  d;
    209  |
    210  |   d = MA_new(1, 4, 56, 3, 5, 7, 19, MA_END);
    211  |
    212  |   MA_prt(d);
    213  |
    214  |   MA_set(&d, 3, 0);
    215  |   MA_set(&d, 7, 0);
    216  |   MA_set(&d, 9, 0);
    217  |   MA_set(&d, 19, 0);
    218  |
    219  |   MA_prt(d);
    220  | }
    221  | #endif