xref: /aosp_15_r20/external/abseil-cpp/absl/log/flags.cc (revision 9356374a3709195abf420251b3e825997ff56c0f)
1 //
2 // Copyright 2022 The Abseil Authors.
3 //
4 // Licensed under the Apache License, Version 2.0 (the "License");
5 // you may not use this file except in compliance with the License.
6 // You may obtain a copy of the License at
7 //
8 //      https://www.apache.org/licenses/LICENSE-2.0
9 //
10 // Unless required by applicable law or agreed to in writing, software
11 // distributed under the License is distributed on an "AS IS" BASIS,
12 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 // See the License for the specific language governing permissions and
14 // limitations under the License.
15 
16 #include "absl/log/internal/flags.h"
17 
18 #include <stddef.h>
19 
20 #include <algorithm>
21 #include <cstdlib>
22 #include <string>
23 
24 #include "absl/base/attributes.h"
25 #include "absl/base/config.h"
26 #include "absl/base/log_severity.h"
27 #include "absl/flags/flag.h"
28 #include "absl/flags/marshalling.h"
29 #include "absl/log/globals.h"
30 #include "absl/log/internal/config.h"
31 #include "absl/log/internal/vlog_config.h"
32 #include "absl/strings/numbers.h"
33 #include "absl/strings/string_view.h"
34 
35 namespace absl {
36 ABSL_NAMESPACE_BEGIN
37 namespace log_internal {
38 namespace {
39 
SyncLoggingFlags()40 void SyncLoggingFlags() {
41   absl::SetFlag(&FLAGS_minloglevel, static_cast<int>(absl::MinLogLevel()));
42   absl::SetFlag(&FLAGS_log_prefix, absl::ShouldPrependLogPrefix());
43 }
44 
RegisterSyncLoggingFlags()45 bool RegisterSyncLoggingFlags() {
46   log_internal::SetLoggingGlobalsListener(&SyncLoggingFlags);
47   return true;
48 }
49 
50 ABSL_ATTRIBUTE_UNUSED const bool unused = RegisterSyncLoggingFlags();
51 
52 template <typename T>
GetFromEnv(const char * varname,T dflt)53 T GetFromEnv(const char* varname, T dflt) {
54   const char* val = ::getenv(varname);
55   if (val != nullptr) {
56     std::string err;
57     ABSL_INTERNAL_CHECK(absl::ParseFlag(val, &dflt, &err), err.c_str());
58   }
59   return dflt;
60 }
61 
StderrThresholdDefault()62 constexpr absl::LogSeverityAtLeast StderrThresholdDefault() {
63   return absl::LogSeverityAtLeast::kError;
64 }
65 
66 }  // namespace
67 }  // namespace log_internal
68 ABSL_NAMESPACE_END
69 }  // namespace absl
70 
71 ABSL_FLAG(int, stderrthreshold,
72           static_cast<int>(absl::log_internal::StderrThresholdDefault()),
73           "Log messages at or above this threshold level are copied to stderr.")
__anon2617cab90202null74     .OnUpdate([] {
75       absl::log_internal::RawSetStderrThreshold(
76           static_cast<absl::LogSeverityAtLeast>(
77               absl::GetFlag(FLAGS_stderrthreshold)));
78     });
79 
80 ABSL_FLAG(int, minloglevel, static_cast<int>(absl::LogSeverityAtLeast::kInfo),
81           "Messages logged at a lower level than this don't actually "
82           "get logged anywhere")
__anon2617cab90302null83     .OnUpdate([] {
84       absl::log_internal::RawSetMinLogLevel(
85           static_cast<absl::LogSeverityAtLeast>(
86               absl::GetFlag(FLAGS_minloglevel)));
87     });
88 
89 ABSL_FLAG(std::string, log_backtrace_at, "",
90           "Emit a backtrace when logging at file:linenum.")
__anon2617cab90402null91     .OnUpdate([] {
92       const std::string log_backtrace_at =
93           absl::GetFlag(FLAGS_log_backtrace_at);
94       if (log_backtrace_at.empty()) {
95         absl::ClearLogBacktraceLocation();
96         return;
97       }
98 
99       const size_t last_colon = log_backtrace_at.rfind(':');
100       if (last_colon == log_backtrace_at.npos) {
101         absl::ClearLogBacktraceLocation();
102         return;
103       }
104 
105       const absl::string_view file =
106           absl::string_view(log_backtrace_at).substr(0, last_colon);
107       int line;
108       if (!absl::SimpleAtoi(
109               absl::string_view(log_backtrace_at).substr(last_colon + 1),
110               &line)) {
111         absl::ClearLogBacktraceLocation();
112         return;
113       }
114       absl::SetLogBacktraceLocation(file, line);
115     });
116 
117 ABSL_FLAG(bool, log_prefix, true,
118           "Prepend the log prefix to the start of each log line")
__anon2617cab90502null119     .OnUpdate([] {
120       absl::log_internal::RawEnableLogPrefix(absl::GetFlag(FLAGS_log_prefix));
121     });
122 
123 ABSL_FLAG(int, v, 0,
124           "Show all VLOG(m) messages for m <= this. Overridable by --vmodule.")
__anon2617cab90602null125     .OnUpdate([] {
126       absl::log_internal::UpdateGlobalVLogLevel(absl::GetFlag(FLAGS_v));
127     });
128 
129 ABSL_FLAG(
130     std::string, vmodule, "",
131     "per-module log verbosity level."
132     " Argument is a comma-separated list of <module name>=<log level>."
133     " <module name> is a glob pattern, matched against the filename base"
134     " (that is, name ignoring .cc/.h./-inl.h)."
135     " A pattern without slashes matches just the file name portion, otherwise"
136     " the whole file path below the workspace root"
137     " (still without .cc/.h./-inl.h) is matched."
138     " ? and * in the glob pattern match any single or sequence of characters"
139     " respectively including slashes."
140     " <log level> overrides any value given by --v.")
__anon2617cab90702null141     .OnUpdate([] {
142       absl::log_internal::UpdateVModule(absl::GetFlag(FLAGS_vmodule));
143     });
144