add option to octect counting parser to set message buffer to be bigg…

makefile

@@ -42,7 +42,7 @@ snake2camel:
 	}' $(file)
 
 .PHONY: bench
-bench: rfc5424/*_test.go rfc5424/machine.go
+bench: rfc5424/*_test.go rfc5424/machine.go octetcounting/performance_test.go
 	go test -bench=. -benchmem -benchtime=5s ./...
 
 .PHONY: tests

nontransparent/parser.go

@@ -218,6 +218,9 @@ func NewParser(options ...syslog.ParserOption) syslog.Parser {
 	return m
 }
 
+// WithMaxMessageLength does nothing for this parser
+func (m *machine) WithMaxMessageLength(length int) {}
+
 // HasBestEffort tells whether the receiving parser has best effort mode on or off.
 func (m *machine) HasBestEffort() bool {
 	return m.bestEffort

octetcounting/parser.go

@@ -12,19 +12,21 @@ import (
 //
 // Use NewParser function to instantiate one.
 type parser struct {
-	msglen     int64
-	s          Scanner
-	internal   syslog.Machine
-	last       Token
-	stepback   bool // Wheter to retrieve the last token or not
-	bestEffort bool // Best effort mode flag
-	emit       syslog.ParserListener
+	msglen           int64
+	maxMessageLength int
+	s                Scanner
+	internal         syslog.Machine
+	last             Token
+	stepback         bool // Wheter to retrieve the last token or not
+	bestEffort       bool // Best effort mode flag
+	emit             syslog.ParserListener
 }
 
 // NewParser returns a syslog.Parser suitable to parse syslog messages sent with transparent - ie. octet counting (RFC 5425) - framing.
 func NewParser(opts ...syslog.ParserOption) syslog.Parser {
 	p := &parser{
-		emit: func(*syslog.Result) { /* noop */ },
+		emit:             func(*syslog.Result) { /* noop */ },
+		maxMessageLength: 8192, // size as per RFC5425#section-4.3.1
 	}
 
 	for _, opt := range opts {
@@ -41,6 +43,10 @@ func NewParser(opts ...syslog.ParserOption) syslog.Parser {
 	return p
 }
 
+func (p *parser) WithMaxMessageLength(length int) {
+	p.maxMessageLength = length
+}
+
 // HasBestEffort tells whether the receiving parser has best effort mode on or off.
 func (p *parser) HasBestEffort() bool {
 	return p.bestEffort
@@ -64,7 +70,7 @@ func (p *parser) WithListener(f syslog.ParserListener) {
 //
 // It stops parsing when an error regarding RFC 5425 is found.
 func (p *parser) Parse(r io.Reader) {
-	p.s = *NewScanner(r)
+	p.s = *NewScanner(r, p.maxMessageLength)
 	p.run()
 }