We want to avoid synchronization overhead when checking if a log message is enabled. Most of the time, most messages will be disabled, so incurring the locking overhead on each message would be too expensive and would discourage developers from creating logs. Furthermore, missing a few messages while the change of state "propagates" to other threads does not affect the correctness of the program.
Note that memory_order_relaxed does not provide a compiler barrier either, so in theory stores into the atomic could be reordered by the optimizer. We have no reason to worry about that because all the writes are done inside a critical section protected by a mutex. The compiler cannot (or should not) reorder operations around those.
Returns
Type
Description
bool
is_enabled(Severity) const
Return true if severity is enabled.
We want to avoid synchronization overhead when checking if a log message is enabled. Most of the time, most messages will be disabled, so incurring the locking overhead on each message would be too expensive and would discourage developers from creating logs. Furthermore, missing a few messages while the change of state "propagates" to other threads does not affect the correctness of the program.
Note that memory_order_relaxed does not provide a compiler barrier either, so in theory stores into the atomic could be reordered by the optimizer. We have no reason to worry about that because all the writes are done inside a critical section protected by a mutex. The compiler cannot (or should not) reorder operations around those.
Parameter
Name
Description
severity
Severity
Returns
Type
Description
bool
set_minimum_severity(Severity)
Parameter
Name
Description
minimum
Severity
Returns
Type
Description
void
minimum_severity() const
Returns
Type
Description
Severity
AddBackend(std::shared_ptr< LogBackend >)
Parameter
Name
Description
backend
std::shared_ptr< LogBackend >
Returns
Type
Description
BackendId
RemoveBackend(BackendId)
Parameter
Name
Description
id
BackendId
Returns
Type
Description
void
ClearBackends()
Returns
Type
Description
void
BackendCount() const
Returns
Type
Description
std::size_t
Log(LogRecord)
Parameter
Name
Description
log_record
LogRecord
Returns
Type
Description
void
Flush()
Flush all the current backends.
Returns
Type
Description
void
static CompileTimeEnabled(Severity)
Return true if the severity is enabled at compile time.
Parameter
Name
Description
level
Severity
Returns
Type
Description
bool constexpr
static Instance()
Return the singleton instance for this application.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Hard to understand","hardToUnderstand","thumb-down"],["Incorrect information or sample code","incorrectInformationOrSampleCode","thumb-down"],["Missing the information/samples I need","missingTheInformationSamplesINeed","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-03-05 UTC."],[[["This page details the `LogSink` class in the Google Cloud C++ client library, which is designed to receive and manage log records, providing a central hub for logging functionality."],["The `LogSink` class allows for the configuration of minimum severity levels for log messages, enabling control over the verbosity of the logs being recorded, and providing the ability to check if specific severities are enabled."],["`LogSink` manages log backends, enabling users to add, remove, clear, and count them, along with providing the ability to flush the backends."],["The class contains features to enable or disable `std::clog` as a logging destination via environmental variables, and also includes methods for compile-time checking of severity levels."],["The `LogSink` documentation lists the different versions available, ranging from the latest release candidate 2.37.0-rc down to 2.10.1, all of which have their own specific documentation pages."]]],[]]
