X-Git-Url: http://git.cielonegro.org/gitweb.cgi?p=Lucu.git;a=blobdiff_plain;f=Network%2FHTTP%2FLucu%2FUtils.hs;h=1070d66f28042193a0337b02f1e9d858d63c9403;hp=d7ace3f8309aab60c21f2c8c6c4362189a05bc73;hb=b22e702f8161447a460847c6e6c97104c150534f;hpb=0b4db5681e3b0b27357a87316822ea3671f8c174

diff --git a/Network/HTTP/Lucu/Utils.hs b/Network/HTTP/Lucu/Utils.hs
index d7ace3f..1070d66 100644
--- a/Network/HTTP/Lucu/Utils.hs
+++ b/Network/HTTP/Lucu/Utils.hs
@@ -1,75 +1,146 @@
--- |Utility functions used internally in the Lucu httpd. These
--- functions may be useful too for something else.
+{-# LANGUAGE
+    FlexibleContexts
+  , OverloadedStrings
+  , UnicodeSyntax
+  #-}
+-- |Utility functions used internally in this package.
 module Network.HTTP.Lucu.Utils
     ( splitBy
-    , joinWith
-    , trim
-    , noCaseEq
-    , isWhiteSpace
     , quoteStr
     , parseWWWFormURLEncoded
+    , uriPathSegments
+    , trim
+
+    , (⊲)
+    , (⊳)
+    , (⋈)
+    , mapM
+
+    , getLastModified
     )
     where
-
-import Control.Monad.Trans
+import Control.Applicative hiding (empty)
+import Control.Monad hiding (mapM)
+import Data.Ascii (Ascii, AsciiBuilder)
+import qualified Data.Ascii as A
+import Data.ByteString (ByteString)
+import qualified Data.ByteString.Char8 as Strict
 import Data.Char
-import Data.List
-import Foreign
-import Foreign.C
+import Data.Collections
+import Data.Collections.BaseInstances ()
+import Data.Monoid.Unicode
+import Data.Ratio
+import Data.Time
+import Data.Time.Clock.POSIX
 import Network.URI
+import Prelude hiding (last, mapM, null, reverse)
+import Prelude.Unicode
+import System.Directory
+import System.Time (ClockTime(..))
+
+-- |>>> splitBy (== ':') "ab:c:def"
+-- ["ab", "c", "def"]
+splitBy ∷ (a → Bool) → [a] → [[a]]
+{-# INLINEABLE splitBy #-}
+splitBy isSep src
+    = case break isSep src of
+        (last , []       ) → [last]
+        (first, _sep:rest) → first : splitBy isSep rest
+
+-- |>>> quoteStr "abc"
+-- "\"abc\""
+--
+-- >>> quoteStr "ab\"c"
+-- "\"ab\\\"c\""
+quoteStr ∷ Ascii → AsciiBuilder
+quoteStr str = A.toAsciiBuilder "\"" ⊕
+               go (A.toByteString str) (∅) ⊕
+               A.toAsciiBuilder "\""
+    where
+      go ∷ Strict.ByteString → AsciiBuilder → AsciiBuilder
+      go bs ab
+          = case Strict.break (≡ '"') bs of
+              (x, y)
+                  | Strict.null y
+                      → ab ⊕ b2ab x
+                  | otherwise
+                      → go (Strict.tail y)
+                           (ab ⊕ b2ab x ⊕ A.toAsciiBuilder "\\\"")
+
+      b2ab ∷ Strict.ByteString → AsciiBuilder
+      b2ab = A.toAsciiBuilder ∘ A.unsafeFromByteString
 
--- |> splitBy (== ':') "ab:c:def"
---  > ==> ["ab", "c", "def"]
-splitBy :: (a -> Bool) -> [a] -> [[a]]
-splitBy isSeparator src
-    = case break isSeparator src
-      of (last , []      ) -> last  : []
-         (first, sep:rest) -> first : splitBy isSeparator rest
+-- |>>> parseWWWFormURLEncoded "aaa=bbb&ccc=ddd"
+-- [("aaa", "bbb"), ("ccc", "ddd")]
+parseWWWFormURLEncoded ∷ Ascii → [(ByteString, ByteString)]
+parseWWWFormURLEncoded src
+    -- THINKME: We could gain some performance by using attoparsec
+    -- here.
+    | src ≡ ""  = []
+    | otherwise = do pairStr ← splitBy (\ c → c ≡ ';' ∨ c ≡ '&') (A.toString src)
+                     let (key, value) = break (≡ '=') pairStr
+                     return ( unescape key
+                            , unescape $ case value of
+                                           ('=':val) → val
+                                           val       → val
+                            )
+    where
+      unescape ∷ String → ByteString
+      unescape = Strict.pack ∘ unEscapeString ∘ (plusToSpace <$>)
 
--- |> joinWith ':' ["ab", "c", "def"]
---  > ==> "ab:c:def"
-joinWith :: [a] -> [[a]] -> [a]
-joinWith separator xs
-    = foldr (++) [] $ intersperse separator xs
+      plusToSpace ∷ Char → Char
+      plusToSpace '+' = ' '
+      plusToSpace c   = c
 
--- |> trim (== '_') "__ab_c__def___"
---  > ==> "ab_c__def"
-trim :: (a -> Bool) -> [a] -> [a]
-trim p = trimTail . trimHead
+-- |>>> uriPathSegments "http://example.com/foo/bar"
+-- ["foo", "bar"]
+uriPathSegments ∷ URI → [ByteString]
+uriPathSegments uri
+    = let reqPathStr = uriPath uri
+          reqPath    = [unEscapeString x | x ← splitBy (≡ '/') reqPathStr, (¬) (null x)]
+      in
+        Strict.pack <$> reqPath
+
+-- |>>> trim "  ab c d "
+-- "ab c d"
+trim ∷ String → String
+trim = reverse ∘ f ∘ reverse ∘ f
     where
-      trimHead = dropWhile p
-      trimTail = reverse . trimHead . reverse
+      f = dropWhile isSpace
 
--- |@'noCaseEq' a b@ is equivalent to @(map toLower a) == (map toLower
--- b)@
-noCaseEq :: String -> String -> Bool
-noCaseEq a b
-    = (map toLower a) == (map toLower b)
+infixr 5 ⊲
+-- | (&#22B2;) = ('<|')
+--
+-- U+22B2, NORMAL SUBGROUP OF
+(⊲) ∷ Sequence α a ⇒ a → α → α
+(⊲) = (<|)
 
--- |@'isWhiteSpace' c@ is True iff c is one of SP, HT, CR and LF.
-isWhiteSpace :: Char -> Bool
-isWhiteSpace = flip elem " \t\r\n"
+infixl 5 ⊳
+-- | (&#22B3;) = ('|>')
+--
+-- U+22B3, CONTAINS AS NORMAL SUBGROUP
+(⊳) ∷ Sequence α a ⇒ α → a → α
+(⊳) = (|>)
 
--- |> quoteStr "abc"
---  > ==> "\"abc\""
+infixr 5 ⋈
+-- | (&#22C8;) = ('><')
 --
---  > quoteStr "ab\"c"
---  > ==> "\"ab\\\"c\""
-quoteStr :: String -> String
-quoteStr str = foldr (++) "" (["\""] ++ map quote str ++ ["\""])
-    where
-      quote :: Char -> String
-      quote '"' = "\\\""
-      quote c   = [c]
+-- U+22C8, BOWTIE
+(⋈) ∷ Sequence α a ⇒ α → α → α
+(⋈) = (><)
 
+-- |Generalised @mapM@ from any 'Foldable' to 'Unfoldable'. Why isn't
+-- this in the @collections-api@?
+mapM ∷ (Foldable α a, Unfoldable β b, Functor m, Monad m)
+     ⇒ (a → m b) → α → m β
+{-# INLINE mapM #-}
+mapM = flip foldrM empty ∘ (flip ((<$>) ∘ flip insert) ∘)
 
--- |> parseWWWFormURLEncoded "aaa=bbb&ccc=ddd"
---  > ==> [("aaa", "bbb"), ("ccc", "ddd")]
-parseWWWFormURLEncoded :: String -> [(String, String)]
-parseWWWFormURLEncoded src
-    | src == "" = []
-    | otherwise = do pairStr <- splitBy (\ c -> c == ';' || c == '&') src
-                     let pair = break (== '=') pairStr
-                     return ( unEscapeString $ fst pair
-                            , unEscapeString $ snd pair
-                            )
+-- |Get the modification time of a given file.
+getLastModified ∷ FilePath → IO UTCTime
+getLastModified = (clockTimeToUTC <$>) ∘ getModificationTime
+    where
+      clockTimeToUTC ∷ ClockTime → UTCTime
+      clockTimeToUTC (TOD sec picoSec)
+          = posixSecondsToUTCTime ∘ fromRational
+            $ sec % 1 + picoSec % (1000 ⋅ 1000 ⋅ 1000 ⋅ 1000)