blob: 0a9d0d6f07fb88e7a7ece985142f13f5e1f4dc19 (
plain)
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
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
|
/*
* Copyright (c) 2021, kleines Filmröllchen <filmroellchen@serenityos.org>.
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibCore/MemoryStream.h>
namespace Core::Stream {
FixedMemoryStream::FixedMemoryStream(Bytes bytes)
: m_bytes(bytes)
{
}
FixedMemoryStream::FixedMemoryStream(ReadonlyBytes bytes)
: m_bytes({ const_cast<u8*>(bytes.data()), bytes.size() })
, m_writing_enabled(false)
{
}
ErrorOr<NonnullOwnPtr<FixedMemoryStream>> FixedMemoryStream::construct(Bytes bytes)
{
return adopt_nonnull_own_or_enomem<FixedMemoryStream>(new (nothrow) FixedMemoryStream(bytes));
}
ErrorOr<NonnullOwnPtr<FixedMemoryStream>> FixedMemoryStream::construct(ReadonlyBytes bytes)
{
return adopt_nonnull_own_or_enomem<FixedMemoryStream>(new (nothrow) FixedMemoryStream(bytes));
}
bool FixedMemoryStream::is_eof() const
{
return m_offset >= m_bytes.size();
}
bool FixedMemoryStream::is_open() const
{
return true;
}
void FixedMemoryStream::close()
{
// FIXME: It doesn't make sense to close a memory stream. Therefore, we don't do anything here. Is that fine?
}
ErrorOr<void> FixedMemoryStream::truncate(off_t)
{
return Error::from_errno(ENOTSUP);
}
ErrorOr<Bytes> FixedMemoryStream::read(Bytes bytes)
{
auto to_read = min(remaining(), bytes.size());
if (to_read == 0)
return Bytes {};
m_bytes.slice(m_offset, to_read).copy_to(bytes);
m_offset += to_read;
return bytes.trim(to_read);
}
ErrorOr<off_t> FixedMemoryStream::seek(i64 offset, SeekMode seek_mode)
{
switch (seek_mode) {
case SeekMode::SetPosition:
if (offset > static_cast<i64>(m_bytes.size()))
return Error::from_string_literal("Offset past the end of the stream memory");
m_offset = offset;
break;
case SeekMode::FromCurrentPosition:
if (offset + static_cast<i64>(m_offset) > static_cast<i64>(m_bytes.size()))
return Error::from_string_literal("Offset past the end of the stream memory");
m_offset += offset;
break;
case SeekMode::FromEndPosition:
if (offset > static_cast<i64>(m_bytes.size()))
return Error::from_string_literal("Offset past the start of the stream memory");
m_offset = m_bytes.size() - offset;
break;
}
return static_cast<off_t>(m_offset);
}
ErrorOr<size_t> FixedMemoryStream::write(ReadonlyBytes bytes)
{
VERIFY(m_writing_enabled);
// FIXME: Can this not error?
auto const nwritten = bytes.copy_trimmed_to(m_bytes.slice(m_offset));
m_offset += nwritten;
return nwritten;
}
ErrorOr<void> FixedMemoryStream::write_entire_buffer(ReadonlyBytes bytes)
{
if (remaining() < bytes.size())
return Error::from_string_literal("Write of entire buffer ends past the memory area");
TRY(write(bytes));
return {};
}
Bytes FixedMemoryStream::bytes()
{
VERIFY(m_writing_enabled);
return m_bytes;
}
ReadonlyBytes FixedMemoryStream::bytes() const
{
return m_bytes;
}
size_t FixedMemoryStream::offset() const
{
return m_offset;
}
size_t FixedMemoryStream::remaining() const
{
return m_bytes.size() - m_offset;
}
}
|
