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
|
#ifndef TAGGED_PAYLOAD_INL_H_
#error "Direct inclusion of this file is not allowed, include tagged_payload.h"
// For the sake of sane code completion.
#include "tagged_payload.h"
#endif
#include <library/cpp/yt/assert/assert.h>
#include <cstring>
namespace NYT::NLogging {
////////////////////////////////////////////////////////////////////////////////
inline TSharedRef TTaggedPayloadBuilder::Flush()
{
return Buffer_.Slice(0, GetLength());
}
template <class T>
void TTaggedPayloadBuilder::AppendPod(const T& value)
{
::memcpy(Preallocate(sizeof(value)), &value, sizeof(value));
Advance(sizeof(value));
}
template <class T>
void TTaggedPayloadBuilder::WritePodAt(size_t offset, const T& value)
{
YT_ASSERT(offset + sizeof(value) <= GetLength());
::memcpy(Begin_ + offset, &value, sizeof(value));
}
////////////////////////////////////////////////////////////////////////////////
inline TStringBuilderBase* TTaggedPayloadWriter::BeginMessage() &
{
YT_ASSERT(!MessageStarted_);
MessageStarted_ = true;
ReserveLengthPrefix();
return &Builder_;
}
inline TTaggedPayloadWriter& TTaggedPayloadWriter::EndMessage() &
{
YT_ASSERT(MessageStarted_ && !MessageEnded_);
MessageEnded_ = true;
BackpatchLengthPrefix();
return *this;
}
inline TStringBuilderBase* TTaggedPayloadWriter::BeginTag(TStringBuf key) &
{
return DoBeginTag(key, /*wellKnown*/ false);
}
inline TStringBuilderBase* TTaggedPayloadWriter::BeginWellKnownTag(TStringBuf key) &
{
return DoBeginTag(key, /*wellKnown*/ true);
}
inline TStringBuilderBase* TTaggedPayloadWriter::DoBeginTag(TStringBuf key, bool wellKnown)
{
YT_ASSERT(MessageEnded_ && !InTag_);
// High bit reserved for the well-known flag.
YT_ASSERT(key.size() < WellKnownTagFlag);
InTag_ = true;
// Reserve the key-size prefix, the key bytes, and the value-size prefix in a single
// capacity check; the value is then formatted in place and EndTag backpatches its size.
auto keySize = static_cast<ui32>(key.size()) | (wellKnown ? WellKnownTagFlag : 0);
char* ptr = Builder_.Preallocate(2 * sizeof(ui32) + key.size());
PrefixOffset_ = Builder_.GetLength() + sizeof(ui32) + key.size();
::memcpy(ptr, &keySize, sizeof(keySize));
::memcpy(ptr + sizeof(keySize), key.data(), key.size());
// The value-size prefix is left uninitialized; EndTag overwrites it.
Builder_.Advance(2 * sizeof(ui32) + key.size());
return &Builder_;
}
inline TTaggedPayloadWriter& TTaggedPayloadWriter::EndTag() &
{
YT_ASSERT(InTag_);
InTag_ = false;
BackpatchLengthPrefix();
return *this;
}
inline TTaggedLogEventPayload TTaggedPayloadWriter::Finish() &
{
YT_ASSERT(MessageEnded_ && !InTag_);
return TTaggedLogEventPayload(Builder_.Flush());
}
inline void TTaggedPayloadWriter::ReserveLengthPrefix()
{
PrefixOffset_ = Builder_.GetLength();
// Reserve a zeroed ui32; backpatched by BackpatchLengthPrefix.
Builder_.AppendPod<ui32>(0);
}
inline void TTaggedPayloadWriter::BackpatchLengthPrefix()
{
Builder_.WritePodAt<ui32>(PrefixOffset_, Builder_.GetLength() - PrefixOffset_ - sizeof(ui32));
}
////////////////////////////////////////////////////////////////////////////////
} // namespace NYT::NLogging
|
