-- file: ch27/SyslogTypes.hs

module SyslogTypes where

-- | Priorities define how important a log message is.

data Priority =

DEBUG -- ^ Debug messages

| INFO -- ^ Information

| NOTICE -- ^ Normal runtime conditions

| WARNING -- ^ General Warnings

| ERROR -- ^ General Errors

| CRITICAL -- ^ Severe situations

| ALERT -- ^ Take immediate action

| EMERGENCY -- ^ System is unusable

deriving (Eq, Ord, Show, Read, Enum)

{- | Facilities are used by the system to determine where messages

are sent. -}

data Facility =

KERN -- ^ Kernel messages

| USER -- ^ General userland messages

| MAIL -- ^ E-Mail system

| DAEMON -- ^ Daemon (server process) messages

| AUTH -- ^ Authentication or security messages

| SYSLOG -- ^ Internal syslog messages

| LPR -- ^ Printer messages

| NEWS -- ^ Usenet news

| UUCP -- ^ UUCP messages

| CRON -- ^ Cron messages

| AUTHPRIV -- ^ Private authentication messages

| FTP -- ^ FTP messages

| LOCAL0

| LOCAL1

| LOCAL2

| LOCAL3

| LOCAL4

| LOCAL5

| LOCAL6

| LOCAL7

deriving (Eq, Show, Read)

facToCode = [

(KERN, 0),

(USER, 1),

(MAIL, 2),

(DAEMON, 3),

(AUTH, 4),

(SYSLOG, 5),

(LPR, 6),

(NEWS, 7),

(UUCP, 8),

(CRON, 9),

(AUTHPRIV, 10),

(FTP, 11),

(LOCAL0, 16),

(LOCAL1, 17),

(LOCAL2, 18),

(LOCAL3, 19),

(LOCAL4, 20),

(LOCAL5, 21),

(LOCAL6, 22),

(LOCAL7, 23)

]

codeToFac = map (\ (x, y) -> (y, x)) facToCode

-- | We can't use enum here because the numbering is discontiguous

codeOfFac :: Facility -> Int

codeOfFac f = case lookup f facToCode of

Just x -> x

_ -> error "Internal error in codeOfFac"

facOfCode :: Int -> Facility

facOfCode f = case lookup f codeToFac of

Just x -> x

_ -> error "Invalid code in facOfCode"