Fix up parseUpToLen(). (#46)

The parseUpToLen function would not handle the max chars limit.
Found when using a syslog client which used > max chars for the
APP-NAME. I changed the syslog client to use max chars and it still
didn't work. There was an off by 1 error. One of the tests even
gave a max chars string and expected an error - changed that test
to try with max+1 chars.

Author: scorptec68

format/rfc6587_test.go

@@ -85,5 +85,5 @@ func (s *FormatSuite) TestRFC6587_GetSplitBadSplit(c *C) {
 	c.Assert(r, NotNil)
 
 	err := scanner.Err()
-	c.Assert(err, ErrorMatches, "strconv.ParseInt: parsing \".2\": invalid syntax")
+	c.Assert(err, ErrorMatches, "strconv.*: parsing \".2\": invalid syntax")
 }

internal/syslogparser/rfc5424/rfc5424.go

@@ -579,7 +579,7 @@ func parseUpToLen(buff []byte, cursor *int, l int, maxLen int, e error) (string,
 
 	max := *cursor + maxLen
 
-	for to = *cursor; (to < max) && (to < l); to++ {
+	for to = *cursor; (to <= max) && (to < l); to++ {
 		if buff[to] == ' ' {
 			found = true
 			break
@@ -588,6 +588,8 @@ func parseUpToLen(buff []byte, cursor *int, l int, maxLen int, e error) (string,
 
 	if found {
 		result = string(buff[*cursor:to])
+	} else if (to > max) {
+		to = max; // don't go past max
 	}
 
 	*cursor = to

internal/syslogparser/rfc5424/rfc5424_test.go

@@ -22,6 +22,7 @@ func (s *Rfc5424TestSuite) TestParser_Valid(c *C) {
 		// no STRUCTURED-DATA
 		"<34>1 2003-10-11T22:14:15.003Z mymachine.example.com su - ID47 - 'su root' failed for lonvick on /dev/pts/8",
 		"<165>1 2003-08-24T05:14:15.000003-07:00 192.0.2.1 myproc 8710 - - %% It's time to make the do-nuts.",
+		"<165>1 2003-08-24T05:14:15.000003-07:00 192.0.2.1 012345678901234567890123456789012345678901234567 8710 - - %% It's time to make the do-nuts.",
 		// with STRUCTURED-DATA
 		`<165>1 2003-10-11T22:14:15.003Z mymachine.example.com evntslog - ID47 [exampleSDID@32473 iut="3" eventSource="Application" eventID="1011"] An application event log entry...`,
 		// STRUCTURED-DATA Only
@@ -60,6 +61,19 @@ func (s *Rfc5424TestSuite) TestParser_Valid(c *C) {
 			"structured_data": "-",
 			"message":         "%% It's time to make the do-nuts.",
 		},
+		syslogparser.LogParts{
+			"priority":        165,
+			"facility":        20,
+			"severity":        5,
+			"version":         1,
+			"timestamp":       time.Date(2003, time.August, 24, 5, 14, 15, 3*10e2, tmpTs.Location()),
+			"hostname":        "192.0.2.1",
+			"app_name":        "012345678901234567890123456789012345678901234567",
+			"proc_id":         "8710",
+			"msg_id":          "-",
+			"structured_data": "-",
+			"message":         "%% It's time to make the do-nuts.",
+		},
 		syslogparser.LogParts{
 			"priority":        165,
 			"facility":        20,
@@ -684,7 +698,7 @@ func (s *Rfc5424TestSuite) TestParseMsgId_Valid(c *C) {
 
 func (s *Rfc5424TestSuite) TestParseMsgId_TooLong(c *C) {
 	// > 32chars
-	buff := []byte("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa ")
+	buff := []byte("aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa ")
 	procId := ""
 
 	s.assertParseMsgId(c, procId, buff, 32, ErrInvalidMsgId)