jcs.org
Serenity Operating System
1/*
2 * Copyright (c) 2020, Liav A. <liavalb@hotmail.co.il>
3 *
4 * SPDX-License-Identifier: BSD-2-Clause
5 */
6
7#include <AK/AllOf.h>
8#include <AK/Hex.h>
9#include <AK/StringBuilder.h>
10#include <AK/UUID.h>
11
12namespace AK {
13
14UUID::UUID(Array<u8, 16> uuid_buffer)
15{
16 uuid_buffer.span().copy_to(m_uuid_buffer);
17}
18
19void UUID::convert_string_view_to_little_endian_uuid(StringView uuid_string_view)
20{
21 VERIFY(uuid_string_view.length() == 36);
22 auto first_unit = MUST(decode_hex(uuid_string_view.substring_view(0, 8)));
23 auto second_unit = MUST(decode_hex(uuid_string_view.substring_view(9, 4)));
24 auto third_unit = MUST(decode_hex(uuid_string_view.substring_view(14, 4)));
25 auto fourth_unit = MUST(decode_hex(uuid_string_view.substring_view(19, 4)));
26 auto fifth_unit = MUST(decode_hex(uuid_string_view.substring_view(24, 12)));
27
28 VERIFY(first_unit.size() == 4 && second_unit.size() == 2
29 && third_unit.size() == 2 && fourth_unit.size() == 2
30 && fifth_unit.size() == 6);
31
32 m_uuid_buffer.span().overwrite(0, first_unit.data(), first_unit.size());
33 m_uuid_buffer.span().overwrite(4, second_unit.data(), second_unit.size());
34 m_uuid_buffer.span().overwrite(6, third_unit.data(), third_unit.size());
35 m_uuid_buffer.span().overwrite(8, fourth_unit.data(), fourth_unit.size());
36 m_uuid_buffer.span().overwrite(10, fifth_unit.data(), fifth_unit.size());
37}
38
39void UUID::convert_string_view_to_mixed_endian_uuid(StringView uuid_string_view)
40{
41 VERIFY(uuid_string_view.length() == 36);
42 auto first_unit = MUST(decode_hex(uuid_string_view.substring_view(0, 8)));
43 auto second_unit = MUST(decode_hex(uuid_string_view.substring_view(9, 4)));
44 auto third_unit = MUST(decode_hex(uuid_string_view.substring_view(14, 4)));
45 auto fourth_unit = MUST(decode_hex(uuid_string_view.substring_view(19, 4)));
46 auto fifth_unit = MUST(decode_hex(uuid_string_view.substring_view(24, 12)));
47
48 VERIFY(first_unit.size() == 4 && second_unit.size() == 2
49 && third_unit.size() == 2 && fourth_unit.size() == 2
50 && fifth_unit.size() == 6);
51
52 // Revert endianness for first 4 bytes
53 for (size_t index = 0; index < 4; index++) {
54 m_uuid_buffer[3 - index] = first_unit[index];
55 }
56
57 // Revert endianness for second 2 bytes and again for 2 bytes
58 for (size_t index = 0; index < 2; index++) {
59 m_uuid_buffer[3 + 2 - index] = second_unit[index];
60 m_uuid_buffer[5 + 2 - index] = third_unit[index];
61 }
62
63 m_uuid_buffer.span().overwrite(8, fourth_unit.data(), fourth_unit.size());
64 m_uuid_buffer.span().overwrite(10, fifth_unit.data(), fifth_unit.size());
65}
66
67UUID::UUID(StringView uuid_string_view, Endianness endianness)
68{
69 if (endianness == Endianness::Little) {
70 convert_string_view_to_little_endian_uuid(uuid_string_view);
71 return;
72 } else if (endianness == Endianness::Mixed) {
73 convert_string_view_to_mixed_endian_uuid(uuid_string_view);
74 return;
75 }
76 VERIFY_NOT_REACHED();
77}
78
79#ifdef KERNEL
80ErrorOr<NonnullOwnPtr<Kernel::KString>> UUID::to_string() const
81{
82 StringBuilder builder(36);
83 auto nibble0 = TRY(encode_hex(m_uuid_buffer.span().trim(4)));
84 TRY(builder.try_append(nibble0->view()));
85 TRY(builder.try_append('-'));
86 auto nibble1 = TRY(encode_hex(m_uuid_buffer.span().slice(4).trim(2)));
87 TRY(builder.try_append(nibble1->view()));
88 TRY(builder.try_append('-'));
89 auto nibble2 = TRY(encode_hex(m_uuid_buffer.span().slice(6).trim(2)));
90 TRY(builder.try_append(nibble2->view()));
91 TRY(builder.try_append('-'));
92 auto nibble3 = TRY(encode_hex(m_uuid_buffer.span().slice(8).trim(2)));
93 TRY(builder.try_append(nibble3->view()));
94 TRY(builder.try_append('-'));
95 auto nibble4 = TRY(encode_hex(m_uuid_buffer.span().slice(10).trim(6)));
96 TRY(builder.try_append(nibble4->view()));
97 return Kernel::KString::try_create(builder.string_view());
98}
99#else
100ErrorOr<String> UUID::to_string() const
101{
102 auto buffer_span = m_uuid_buffer.span();
103 StringBuilder builder(36);
104 TRY(builder.try_append(encode_hex(buffer_span.trim(4)).view()));
105 TRY(builder.try_append('-'));
106 TRY(builder.try_append(encode_hex(buffer_span.slice(4, 2)).view()));
107 TRY(builder.try_append('-'));
108 TRY(builder.try_append(encode_hex(buffer_span.slice(6, 2)).view()));
109 TRY(builder.try_append('-'));
110 TRY(builder.try_append(encode_hex(buffer_span.slice(8, 2)).view()));
111 TRY(builder.try_append('-'));
112 TRY(builder.try_append(encode_hex(buffer_span.slice(10, 6)).view()));
113 return builder.to_string();
114}
115#endif
116
117bool UUID::is_zero() const
118{
119 return all_of(m_uuid_buffer, [](auto const octet) { return octet == 0; });
120}
121
122}