2 * Copyright (C) 2007 Michael Brown <mbrown@fensystems.co.uk>.
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License as
6 * published by the Free Software Foundation; either version 2 of the
7 * License, or any later version.
9 * This program is distributed in the hope that it will be useful, but
10 * WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
20 FILE_LICENCE ( GPL2_OR_LATER );
23 #include <ipxe/bitmap.h>
27 * Bitmaps for multicast downloads
35 * @v new_length New length of bitmap, in bits
36 * @ret rc Return status code
38 int bitmap_resize ( struct bitmap *bitmap, unsigned int new_length ) {
39 unsigned int old_num_blocks;
40 unsigned int new_num_blocks;
42 bitmap_block_t *new_blocks;
44 old_num_blocks = BITMAP_INDEX ( bitmap->length + BITMAP_BLKSIZE - 1 );
45 new_num_blocks = BITMAP_INDEX ( new_length + BITMAP_BLKSIZE - 1 );
47 if ( old_num_blocks != new_num_blocks ) {
48 new_size = ( new_num_blocks * sizeof ( bitmap->blocks[0] ) );
49 new_blocks = realloc ( bitmap->blocks, new_size );
51 DBGC ( bitmap, "Bitmap %p could not resize to %d "
52 "bits\n", bitmap, new_length );
55 bitmap->blocks = new_blocks;
57 bitmap->length = new_length;
59 while ( old_num_blocks < new_num_blocks ) {
60 bitmap->blocks[old_num_blocks++] = 0;
63 DBGC ( bitmap, "Bitmap %p resized to %d bits\n", bitmap, new_length );
72 * @ret is_set Bit is set
74 int bitmap_test ( struct bitmap *bitmap, unsigned int bit ) {
75 unsigned int index = BITMAP_INDEX ( bit );
76 bitmap_block_t mask = BITMAP_MASK ( bit );
78 if ( bit >= bitmap->length )
80 return ( ( bitmap->blocks[index] & mask ) != 0 );
89 void bitmap_set ( struct bitmap *bitmap, unsigned int bit ) {
90 unsigned int index = BITMAP_INDEX ( bit );
91 bitmap_block_t mask = BITMAP_MASK ( bit );
93 DBGC ( bitmap, "Bitmap %p setting bit %d\n", bitmap, bit );
96 bitmap->blocks[index] |= mask;
98 /* Update first gap counter */
99 while ( bitmap_test ( bitmap, bitmap->first_gap ) ) {