Source File modules/ma/bitmask.c

    1    | /***************************************
    2    |   $Revision: 1.7 $
    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   |
    42   | #include "globaldefs.h"
    43   |
    44   | void MA_free(mask_t *m) {
    45   |   wr_free(m);
    46   | } /* MA_free() */
    47   |
    48   | int MA_isset(mask_t d, int b) {
    49   |   return(
    50   |  (d.data[b / MASK_BITS_BASESIZE] &(1 <<(b % MASK_BITS_BASESIZE)))
    51   |    > 0);
    52   | }
    53   |
    54   | void MA_set(mask_t *m_ptr, unsigned b, int v) {
    55   |   assert(b < MASK_MAX);
    56   |   assert(v == 0 || v == 1);
    57   |
    58   |   if(v == 1)
    59   |     m_ptr->data[b / MASK_BITS_BASESIZE] |=(1 <<(b % MASK_BITS_BASESIZE));
    60   |   else
    61   |     m_ptr->data[b / MASK_BITS_BASESIZE] &= ~(1 <<(b % MASK_BITS_BASESIZE));
    62   | }
    63   |
    64   | void MA_clear(mask_t *m_ptr) {
    65   |   memset(m_ptr, 0, sizeof(mask_t));
    66   | } /* MA_clear() */
    67   |
    68   |
    69   | /* set bits in dptr. variable number of args, terminated by MA_END */
    70   | mask_t MA_new(int n,...) {
    71   |   va_list         ap;
    72   |   mask_t d;
    73   |
    74   |   MA_clear(&d);
    75   |
    76   |   /* cover the "empty mask" case => MA_new(MA_END) invoked */
    77   |   for ( va_start(ap, n); n != MA_END; n = va_arg(ap, int) ) {
    78   |       MA_set(&d, n, 1);
    79   |   }
    80   |   va_end(ap);
    81   |
    82   |   return d;
    83   | }
    84   |
    85   |
    86   | void MA_prt(mask_t m) {
    87   |   int  i;
    88   |
    89   |   for (i = 0; i < MASK_MAX; i++) {
    90   |     printf("%d", MA_isset(m, i));
    91   |   }
    92   |
    93   |   printf("\n");
    94   |
    95   |   for (i = 0; i < MASK_BITS_WORDS; i++) {
    96   |     printf("0x%0*X ", 2 * sizeof(MASK_BITS_BASETYPE), m.data[i]);
    97   |   }
    98   |
    99   |   printf("\n");
    100  | }
    101  |
    102  | /* Perform a logical AND on two masks.
    103  |    Author: ottrey
    104  |    Date: Tue Jul  6 13:28:24 CEST 1999
    105  |    NB: This operation could/should be done a word at a time?
    106  | */
    107  | mask_t MA_and(mask_t a, mask_t b) {
    108  |   mask_t c;
    109  |   int i;
    110  |
    111  |   for (i=0; i < MASK_BITS_WORDS; i++ )  {
    112  |     c.data[i] = a.data[i] & b.data[i];
    113  |   }
    114  |   return c;
    115  | } /* MA_and() */
    116  |
    117  | /* Perform a logical XOR on two masks.
    118  |    Author: ottrey
    119  |    Date: Thu Jul  8 14:50:14 CEST 1999
    120  |    NB: This operation could/should be done a word at a time?
    121  | */
    122  | mask_t MA_xor(mask_t a, mask_t b) {
    123  |   mask_t c;
    124  |   int i;
    125  |
    126  |   for (i=0; i < MASK_BITS_WORDS; i++ )  {
    127  |     c.data[i] = a.data[i] ^ b.data[i];
    128  |   }
    129  |
    130  |   return c;
    131  |
    132  | } /* MA_xor() */
    133  |
    134  | /* Perform a logical OR on two masks.
    135  |    Author: ottrey
    136  |    Date: Thu Jul  8 16:34:34 CEST 1999
    137  |    NB: This operation could/should be done a word at a time?
    138  | */
    139  | mask_t MA_or(mask_t a, mask_t b) {
    140  |   mask_t c;
    141  |   int i;
    142  |
    143  |   for (i=0; i < MASK_BITS_WORDS; i++ )  {
    144  |     c.data[i] = a.data[i] | b.data[i];
    145  |   }
    146  |
    147  |   return c;
    148  |
    149  | } /* MA_or() */
    150  |
    151  | /* Counts the number of bits set. */
    152  | int MA_bitcount(mask_t m) {
    153  |   int  i;
    154  |   int count=0;
    155  |
    156  |   for (i=0; i < MASK_MAX; i++) {
    157  |     count += MA_isset(m, i);
    158  |   }
    159  |
    160  |   return count;
    161  |
    162  | } /* MA_bitcount() */
    163  |
    164  | /* Convert the bitmap to a string comprising of tokens from an array of tokens.
    165  |    Author: ottrey
    166  |    Date: Tue Jul  6 13:28:24 CEST 1999
    167  | */
    168  | char *MA_to_string(mask_t mask, char * const *tokens) {
    169  |   char *str;
    170  |   char str_buf[STR_L];
    171  |   int count;
    172  |   int i;
    173  |   int length;
    174  |
    175  |   strcpy(str_buf, "");
    176  |
    177  |   count=0;
    178  |   sprintf(str_buf, "{");
    179  |   for (i=0;  tokens[i] != NULL; i++) {
    180  |     if ( MA_isset(mask, i) != 0) {
    181  |       strcat(str_buf, tokens[i]);
    182  |       strcat(str_buf, ",");
    183  |       count++;
    184  |     }
    185  |   }
    186  |   if (count == 0) {
    187  |     strcat(str_buf, "NULL ");
    188  |   }
    189  |   length = strlen(str_buf);
    190  |   str_buf[length-1] = '}';
    191  |
    192  |   str = (char *)calloc(1, strlen(str_buf)+1);
    193  |   strcpy(str, str_buf);
    194  |
    195  |   return str;
    196  |
    197  | } /* MA_to_string() */
    198  |
    199  | #ifdef MODULE_TEST
    200  | void
    201  | main() {
    202  |   mask_t  d;
    203  |
    204  |   d = MA_new(1, 4, 56, 3, 5, 7, 19, MA_END);
    205  |
    206  |   MA_prt(d);
    207  |
    208  |   MA_set(&d, 3, 0);
    209  |   MA_set(&d, 7, 0);
    210  |   MA_set(&d, 9, 0);
    211  |   MA_set(&d, 19, 0);
    212  |
    213  |   MA_prt(d);
    214  | }
    215  | #endif