1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
|
//! Bitmap Operations
pub fn set_bit(bitmap: []u8, bit_index: u64) void {
const byte_index = bit_index / 8;
const bit_offset: u3 = @truncate(bit_index % 8);
if (byte_index < bitmap.len) {
bitmap[byte_index] |= @as(u8, 1) << bit_offset;
}
}
pub fn clear_bit(bitmap: []u8, bit_index: u64) void {
const byte_index = bit_index / 8;
const bit_offset: u3 = @truncate(bit_index % 8);
if (byte_index < bitmap.len) {
bitmap[byte_index] &= ~(@as(u8, 1) << bit_offset);
}
}
pub fn test_bit(bitmap: []const u8, bit_index: u64) bool {
const byte_index = bit_index / 8;
const bit_offset: u3 = @truncate(bit_index % 8);
if (byte_index < bitmap.len) {
return (bitmap[byte_index] & (@as(u8, 1) << bit_offset)) != 0;
}
return true;
}
pub fn set_range(bitmap: []u8, start_bit: u64, count: u64) void {
var bit_index = start_bit;
const end_bit = start_bit + count;
while (bit_index < end_bit) : (bit_index += 1) {
set_bit(bitmap, bit_index);
}
}
pub fn clear_range(bitmap: []u8, start_bit: u64, count: u64) void {
var bit_index = start_bit;
const end_bit = start_bit + count;
while (bit_index < end_bit) : (bit_index += 1) {
clear_bit(bitmap, bit_index);
}
}
pub fn find_first_clear(bitmap: []const u8, start_bit: u64, max_bit: u64) ?u64 {
var bit_index = start_bit;
while (bit_index < max_bit) : (bit_index += 1) {
if (!test_bit(bitmap, bit_index)) {
return bit_index;
}
}
return null;
}
pub fn find_contiguous_clear(bitmap: []const u8, start_bit: u64, max_bit: u64, count: u64) ?u64 {
var bit_index = start_bit;
while (bit_index + count <= max_bit) {
var found = true;
var check_index: u64 = 0;
while (check_index < count) : (check_index += 1) {
if (test_bit(bitmap, bit_index + check_index)) {
found = false;
bit_index += check_index + 1;
break;
}
}
if (found) {
return bit_index;
}
}
return null;
}
pub fn count_clear_bits(bitmap: []const u8, max_bit: u64) u64 {
var count: u64 = 0;
var bit_index: u64 = 0;
while (bit_index < max_bit) : (bit_index += 1) {
if (!test_bit(bitmap, bit_index)) {
count += 1;
}
}
return count;
}
|
