44 lines
1.3 KiB
Go
44 lines
1.3 KiB
Go
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package migration
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import "github.com/btcsuite/btclog"
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// log is a logger that is initialized with no output filters. This
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// means the package will not perform any logging by default until the caller
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// requests it.
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var log btclog.Logger
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// The default amount of logging is none.
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func init() {
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DisableLog()
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}
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// DisableLog disables all library log output. Logging output is disabled
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// by default until either UseLogger or SetLogWriter are called.
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func DisableLog() {
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UseLogger(btclog.Disabled)
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}
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// UseLogger uses a specified Logger to output package logging info.
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// This should be used in preference to SetLogWriter if the caller is also
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// using btclog.
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func UseLogger(logger btclog.Logger) {
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log = logger
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}
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// LogClosure is a closure that can be printed with %v to be used to
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// generate expensive-to-create data for a detailed log level and avoid doing
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// the work if the data isn't printed.
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type logClosure func() string
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// String invokes the log closure and returns the results string.
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func (c logClosure) String() string {
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return c()
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}
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// newLogClosure returns a new closure over the passed function which allows
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// it to be used as a parameter in a logging function that is only invoked when
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// the logging level is such that the message will actually be logged.
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func newLogClosure(c func() string) logClosure {
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return logClosure(c)
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}
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