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
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
|
// Copyright 2017 The Abseil Authors.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#ifndef ABSL_BASE_LOG_SEVERITY_H_
#define ABSL_BASE_LOG_SEVERITY_H_
#include <array>
#include <ostream>
#include "absl/base/attributes.h"
#include "absl/base/config.h"
namespace absl {
ABSL_NAMESPACE_BEGIN
// absl::LogSeverity
//
// Four severity levels are defined. Logging APIs should terminate the program
// when a message is logged at severity `kFatal`; the other levels have no
// special semantics.
//
// Values other than the four defined levels (e.g. produced by `static_cast`)
// are valid, but their semantics when passed to a function, macro, or flag
// depend on the function, macro, or flag. The usual behavior is to normalize
// such values to a defined severity level, however in some cases values other
// than the defined levels are useful for comparison.
//
// Example:
//
// // Effectively disables all logging:
// SetMinLogLevel(static_cast<absl::LogSeverity>(100));
//
// Abseil flags may be defined with type `LogSeverity`. Dependency layering
// constraints require that the `AbslParseFlag()` overload be declared and
// defined in the flags library itself rather than here. The `AbslUnparseFlag()`
// overload is defined there as well for consistency.
//
// absl::LogSeverity Flag String Representation
//
// An `absl::LogSeverity` has a string representation used for parsing
// command-line flags based on the enumerator name (e.g. `kFatal`) or
// its unprefixed name (without the `k`) in any case-insensitive form. (E.g.
// "FATAL", "fatal" or "Fatal" are all valid.) Unparsing such flags produces an
// unprefixed string representation in all caps (e.g. "FATAL") or an integer.
//
// Additionally, the parser accepts arbitrary integers (as if the type were
// `int`).
//
// Examples:
//
// --my_log_level=kInfo
// --my_log_level=INFO
// --my_log_level=info
// --my_log_level=0
//
// `DFATAL` and `kLogDebugFatal` are similarly accepted.
//
// Unparsing a flag produces the same result as `absl::LogSeverityName()` for
// the standard levels and a base-ten integer otherwise.
enum class LogSeverity : int {
kInfo = 0,
kWarning = 1,
kError = 2,
kFatal = 3,
};
// LogSeverities()
//
// Returns an iterable of all standard `absl::LogSeverity` values, ordered from
// least to most severe.
constexpr std::array<absl::LogSeverity, 4> LogSeverities() {
return {{absl::LogSeverity::kInfo, absl::LogSeverity::kWarning,
absl::LogSeverity::kError, absl::LogSeverity::kFatal}};
}
// `absl::kLogDebugFatal` equals `absl::LogSeverity::kFatal` in debug builds
// (i.e. when `NDEBUG` is not defined) and `absl::LogSeverity::kError`
// otherwise. Avoid ODR-using this variable as it has internal linkage and thus
// distinct storage in different TUs.
#ifdef NDEBUG
static constexpr absl::LogSeverity kLogDebugFatal = absl::LogSeverity::kError;
#else
static constexpr absl::LogSeverity kLogDebugFatal = absl::LogSeverity::kFatal;
#endif
// LogSeverityName()
//
// Returns the all-caps string representation (e.g. "INFO") of the specified
// severity level if it is one of the standard levels and "UNKNOWN" otherwise.
constexpr const char* LogSeverityName(absl::LogSeverity s) {
return s == absl::LogSeverity::kInfo
? "INFO"
: s == absl::LogSeverity::kWarning
? "WARNING"
: s == absl::LogSeverity::kError
? "ERROR"
: s == absl::LogSeverity::kFatal ? "FATAL" : "UNKNOWN";
}
// NormalizeLogSeverity()
//
// Values less than `kInfo` normalize to `kInfo`; values greater than `kFatal`
// normalize to `kError` (**NOT** `kFatal`).
constexpr absl::LogSeverity NormalizeLogSeverity(absl::LogSeverity s) {
return s < absl::LogSeverity::kInfo
? absl::LogSeverity::kInfo
: s > absl::LogSeverity::kFatal ? absl::LogSeverity::kError : s;
}
constexpr absl::LogSeverity NormalizeLogSeverity(int s) {
return absl::NormalizeLogSeverity(static_cast<absl::LogSeverity>(s));
}
// operator<<
//
// The exact representation of a streamed `absl::LogSeverity` is deliberately
// unspecified; do not rely on it.
std::ostream& operator<<(std::ostream& os, absl::LogSeverity s);
// Enums representing a lower bound for LogSeverity. APIs that only operate on
// messages of at least a certain level (for example, `SetMinLogLevel()`) use
// this type to specify that level. absl::LogSeverityAtLeast::kInfinity is
// a level above all threshold levels and therefore no log message will
// ever meet this threshold.
enum class LogSeverityAtLeast : int {
kInfo = static_cast<int>(absl::LogSeverity::kInfo),
kWarning = static_cast<int>(absl::LogSeverity::kWarning),
kError = static_cast<int>(absl::LogSeverity::kError),
kFatal = static_cast<int>(absl::LogSeverity::kFatal),
kInfinity = 1000,
};
std::ostream& operator<<(std::ostream& os, absl::LogSeverityAtLeast s);
// Enums representing an upper bound for LogSeverity. APIs that only operate on
// messages of at most a certain level (for example, buffer all messages at or
// below a certain level) use this type to specify that level.
// absl::LogSeverityAtMost::kNegativeInfinity is a level below all threshold
// levels and therefore will exclude all log messages.
enum class LogSeverityAtMost : int {
kNegativeInfinity = -1000,
kInfo = static_cast<int>(absl::LogSeverity::kInfo),
kWarning = static_cast<int>(absl::LogSeverity::kWarning),
kError = static_cast<int>(absl::LogSeverity::kError),
kFatal = static_cast<int>(absl::LogSeverity::kFatal),
};
std::ostream& operator<<(std::ostream& os, absl::LogSeverityAtMost s);
#define COMPOP(op1, op2, T) \
constexpr bool operator op1(absl::T lhs, absl::LogSeverity rhs) { \
return static_cast<absl::LogSeverity>(lhs) op1 rhs; \
} \
constexpr bool operator op2(absl::LogSeverity lhs, absl::T rhs) { \
return lhs op2 static_cast<absl::LogSeverity>(rhs); \
}
// Comparisons between `LogSeverity` and `LogSeverityAtLeast`/
// `LogSeverityAtMost` are only supported in one direction.
// Valid checks are:
// LogSeverity >= LogSeverityAtLeast
// LogSeverity < LogSeverityAtLeast
// LogSeverity <= LogSeverityAtMost
// LogSeverity > LogSeverityAtMost
COMPOP(>, <, LogSeverityAtLeast)
COMPOP(<=, >=, LogSeverityAtLeast)
COMPOP(<, >, LogSeverityAtMost)
COMPOP(>=, <=, LogSeverityAtMost)
#undef COMPOP
ABSL_NAMESPACE_END
} // namespace absl
#endif // ABSL_BASE_LOG_SEVERITY_H_
|
