Release v0.1.0

vendor/github.com/lightninglabs/neutrino/blockntfns/log.go

@@ -0,0 +1,43 @@
+package blockntfns
+
+import "github.com/btcsuite/btclog"
+
+// log is a logger that is initialized with no output filters.  This
+// means the package will not perform any logging by default until the caller
+// requests it.
+var log btclog.Logger
+
+// The default amount of logging is none.
+func init() {
+	DisableLog()
+}
+
+// DisableLog disables all library log output.  Logging output is disabled
+// by default until either UseLogger or SetLogWriter are called.
+func DisableLog() {
+	UseLogger(btclog.Disabled)
+}
+
+// UseLogger uses a specified Logger to output package logging info.
+// This should be used in preference to SetLogWriter if the caller is also
+// using btclog.
+func UseLogger(logger btclog.Logger) {
+	log = logger
+}
+
+// LogClosure is a closure that can be printed with %v to be used to
+// generate expensive-to-create data for a detailed log level and avoid doing
+// the work if the data isn't printed.
+type logClosure func() string
+
+// String invokes the log closure and returns the results string.
+func (c logClosure) String() string {
+	return c()
+}
+
+// newLogClosure returns a new closure over the passed function which allows
+// it to be used as a parameter in a logging function that is only invoked when
+// the logging level is such that the message will actually be logged.
+func newLogClosure(c func() string) logClosure {
+	return logClosure(c)
+}