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Diffstat (limited to 'src/Network/SocketLike.hs')
-rw-r--r-- | src/Network/SocketLike.hs | 124 |
1 files changed, 0 insertions, 124 deletions
diff --git a/src/Network/SocketLike.hs b/src/Network/SocketLike.hs deleted file mode 100644 index d533dd7f..00000000 --- a/src/Network/SocketLike.hs +++ /dev/null | |||
@@ -1,124 +0,0 @@ | |||
1 | {-# LANGUAGE GeneralizedNewtypeDeriving #-} | ||
2 | {-# LANGUAGE CPP #-} | ||
3 | -- | | ||
4 | -- | ||
5 | -- A socket could be used indirectly via a 'System.IO.Handle' or a conduit from | ||
6 | -- Michael Snoyman's conduit package. But doing so presents an encapsulation | ||
7 | -- problem. Do we allow access to the underlying socket and trust that it wont | ||
8 | -- be used in an unsafe way? Or do we protect it at the higher level and deny | ||
9 | -- access to various state information? | ||
10 | -- | ||
11 | -- The 'SocketLike' class enables the approach that provides a safe wrapper to | ||
12 | -- the underlying socket and gives access to various state information without | ||
13 | -- enabling direct reads or writes. | ||
14 | module Network.SocketLike | ||
15 | ( SocketLike(..) | ||
16 | , RestrictedSocket | ||
17 | , restrictSocket | ||
18 | , restrictHandleSocket | ||
19 | -- * Re-exports | ||
20 | -- | ||
21 | -- | To make the 'SocketLike' methods less awkward to use, the types | ||
22 | -- 'CUInt', 'SockAddr', and 'PortNumber' are re-exported. | ||
23 | , CUInt | ||
24 | , PortNumber | ||
25 | , SockAddr(..) | ||
26 | ) where | ||
27 | |||
28 | import Network.Socket | ||
29 | ( PortNumber | ||
30 | , SockAddr | ||
31 | ) | ||
32 | import Foreign.C.Types ( CUInt ) | ||
33 | |||
34 | import qualified Network.Socket as NS | ||
35 | import System.IO (Handle,hClose,hIsOpen) | ||
36 | |||
37 | -- | A safe (mostly read-only) interface to a 'NS.Socket'. Note that despite | ||
38 | -- how this class is named, it provides no access to typical 'NS.Socket' uses | ||
39 | -- like sending or receiving network packets. | ||
40 | class SocketLike sock where | ||
41 | -- | See 'NS.getSocketName' | ||
42 | getSocketName :: sock -> IO SockAddr | ||
43 | -- | See 'NS.getPeerName' | ||
44 | getPeerName :: sock -> IO SockAddr | ||
45 | -- | See 'NS.getPeerCred' | ||
46 | getPeerCred :: sock -> IO (CUInt, CUInt, CUInt) | ||
47 | -- | See 'NS.socketPort' | ||
48 | socketPort :: sock -> IO PortNumber | ||
49 | -- | See 'NS.sIsConnected' | ||
50 | -- | ||
51 | -- __Warning__: Don't rely on this method if it's possible the socket was | ||
52 | -- converted into a 'Handle'. | ||
53 | sIsConnected :: sock -> IO Bool | ||
54 | -- | See 'NS.sIsBound' | ||
55 | sIsBound :: sock -> IO Bool | ||
56 | -- | See 'NS.sIsListening' | ||
57 | sIsListening :: sock -> IO Bool | ||
58 | -- | See 'NS.sIsReadable' | ||
59 | sIsReadable :: sock -> IO Bool | ||
60 | -- | See 'NS.sIsWritable' | ||
61 | sIsWritable :: sock -> IO Bool | ||
62 | |||
63 | -- | This is the only exposed write-access method to the | ||
64 | -- underlying state. Usually implemented by 'NS.close' | ||
65 | sClose :: sock -> IO () | ||
66 | |||
67 | instance SocketLike NS.Socket where | ||
68 | getSocketName = NS.getSocketName | ||
69 | getPeerName = NS.getPeerName | ||
70 | getPeerCred = NS.getPeerCred | ||
71 | socketPort = NS.socketPort | ||
72 | #if MIN_VERSION_network(2,4,0) | ||
73 | sIsConnected = NS.isConnected -- warning: this is always False if the socket | ||
74 | -- was converted to a Handle | ||
75 | sIsBound = NS.isBound | ||
76 | sIsListening = NS.isListening | ||
77 | sIsReadable = NS.isReadable | ||
78 | sIsWritable = NS.isWritable | ||
79 | sClose = NS.close | ||
80 | #else | ||
81 | sIsConnected = NS.sIsConnected -- warning: this is always False if the socket | ||
82 | -- was converted to a Handle | ||
83 | sIsBound = NS.sIsBound | ||
84 | sIsListening = NS.sIsListening | ||
85 | sIsReadable = NS.sIsReadable | ||
86 | sIsWritable = NS.sIsWritable | ||
87 | sClose = NS.sClose | ||
88 | #endif | ||
89 | |||
90 | |||
91 | -- | An encapsulated socket. Data reads and writes are not possible. | ||
92 | data RestrictedSocket = Restricted (Maybe Handle) NS.Socket deriving Show | ||
93 | |||
94 | instance SocketLike RestrictedSocket where | ||
95 | getSocketName (Restricted mb sock) = NS.getSocketName sock | ||
96 | getPeerName (Restricted mb sock) = NS.getPeerName sock | ||
97 | getPeerCred (Restricted mb sock) = NS.getPeerCred sock | ||
98 | socketPort (Restricted mb sock) = NS.socketPort sock | ||
99 | #if MIN_VERSION_network(2,4,0) | ||
100 | sIsConnected (Restricted mb sock) = maybe (NS.isConnected sock) (hIsOpen) mb | ||
101 | sIsBound (Restricted mb sock) = NS.isBound sock | ||
102 | sIsListening (Restricted mb sock) = NS.isListening sock | ||
103 | sIsReadable (Restricted mb sock) = NS.isReadable sock | ||
104 | sIsWritable (Restricted mb sock) = NS.isWritable sock | ||
105 | sClose (Restricted mb sock) = maybe (NS.close sock) (\h -> hClose h >> NS.close sock) mb | ||
106 | #else | ||
107 | sIsConnected (Restricted mb sock) = maybe (NS.sIsConnected sock) (hIsOpen) mb | ||
108 | sIsBound (Restricted mb sock) = NS.sIsBound sock | ||
109 | sIsListening (Restricted mb sock) = NS.sIsListening sock | ||
110 | sIsReadable (Restricted mb sock) = NS.sIsReadable sock | ||
111 | sIsWritable (Restricted mb sock) = NS.sIsWritable sock | ||
112 | sClose (Restricted mb sock) = maybe (NS.sClose sock) (\h -> hClose h >> NS.sClose sock) mb | ||
113 | #endif | ||
114 | |||
115 | -- | Create a 'RestrictedSocket' that explicitly disallows sending or | ||
116 | -- receiving data. | ||
117 | restrictSocket :: NS.Socket -> RestrictedSocket | ||
118 | restrictSocket socket = Restricted Nothing socket | ||
119 | |||
120 | -- | Build a 'RestrictedSocket' for which 'sClose' will close the given | ||
121 | -- 'Handle'. It is intended that this 'Handle' was obtained via | ||
122 | -- 'NS.socketToHandle'. | ||
123 | restrictHandleSocket :: Handle -> NS.Socket -> RestrictedSocket | ||
124 | restrictHandleSocket h socket = Restricted (Just h) socket | ||