1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
|
{- P2P protocol, partial IO implementation
-
- Copyright 2016 Joey Hess <id@joeyh.name>
-
- Licensed under the GNU GPL version 3 or higher.
-}
{-# LANGUAGE RankNTypes, CPP #-}
module Remote.Helper.P2P.IO
( RunProto
, runNetProtoHandle
) where
import Remote.Helper.P2P
import Utility.Process
import Git
import Git.Command
import Utility.SafeCommand
import Utility.SimpleProtocol
import Utility.Exception
import Control.Monad
import Control.Monad.Free
import Control.Monad.IO.Class
import System.Exit (ExitCode(..))
import System.IO
import Control.Concurrent
import Control.Concurrent.Async
import qualified Data.ByteString as B
import qualified Data.ByteString.Lazy as L
type RunProto = forall a m. (MonadIO m, MonadMask m) => Proto a -> m a
data S = S
{ repo :: Repo
, ihdl :: Handle
, ohdl :: Handle
}
-- Implementation of the protocol, communicating with a peer
-- over a Handle. No Local actions will be run.
runNetProtoHandle :: (MonadIO m, MonadMask m) => Handle -> Handle -> Repo -> Proto a -> m a
runNetProtoHandle i o r = go
where
go :: RunProto
go (Pure a) = pure a
go (Free (Net n)) = runNetHandle (S r i o) go n
go (Free (Local _)) = error "local actions not allowed"
runNetHandle :: (MonadIO m, MonadMask m) => S -> RunProto -> NetF (Proto a) -> m a
runNetHandle s runner f = case f of
SendMessage m next -> do
liftIO $ do
hPutStrLn (ohdl s) (unwords (formatMessage m))
hFlush (ohdl s)
runner next
ReceiveMessage next -> do
l <- liftIO $ hGetLine (ihdl s)
case parseMessage l of
Just m -> runner (next m)
Nothing -> runner $ do
let e = ERROR $ "protocol parse error: " ++ show l
net $ sendMessage e
next e
SendBytes _len b next -> do
liftIO $ do
L.hPut (ohdl s) b
hFlush (ohdl s)
runner next
ReceiveBytes (Len n) next -> do
b <- liftIO $ L.hGet (ihdl s) (fromIntegral n)
runner (next b)
CheckAuthToken u t next -> do
authed <- return True -- TODO XXX FIXME really check
runner (next authed)
Relay hin hout next ->
runRelay runner hin hout >>= runner . next
RelayService service next ->
runRelayService s runner service >> runner next
runRelay
:: MonadIO m
=> RunProto
-> RelayHandle
-> RelayHandle
-> m ExitCode
runRelay runner (RelayHandle hout) (RelayHandle hin) = liftIO $
bracket setup cleanup go
where
setup = do
v <- newEmptyMVar
void $ forkIO $ relayFeeder runner v
void $ forkIO $ relayReader v hout
return v
cleanup _ = do
hClose hin
hClose hout
go v = relayHelper runner v hin
runRelayService
:: MonadIO m
=> S
-> RunProto
-> Service
-> m ()
runRelayService s runner service = liftIO $ bracket setup cleanup go
where
cmd = case service of
UploadPack -> "upload-pack"
ReceivePack -> "receive-pack"
serviceproc = gitCreateProcess
[ Param cmd
, File (repoPath (repo s))
] (repo s)
setup = do
(Just hin, Just hout, _, pid) <- createProcess serviceproc
{ std_out = CreatePipe
, std_in = CreatePipe
}
v <- newEmptyMVar
feeder <- async $ relayFeeder runner v
reader <- async $ relayReader v hout
waiter <- async $ waitexit v pid
return (v, feeder, reader, waiter, hin, hout, pid)
cleanup (_, feeder, reader, waiter, hin, hout, pid) = do
hPutStrLn stderr "!!!!\n\nIN CLEANUP"
hFlush stderr
hClose hin
hClose hout
cancel reader
cancel waiter
void $ waitForProcess pid
go (v, _, _, _, hin, _, _) = do
exitcode <- relayHelper runner v hin
runner $ net $ relayToPeer (RelayDone exitcode)
waitexit v pid = putMVar v . RelayDone =<< waitForProcess pid
-- Processes RelayData as it is put into the MVar.
relayHelper :: RunProto -> MVar RelayData -> Handle -> IO ExitCode
relayHelper runner v hin = loop
where
loop = do
d <- takeMVar v
case d of
RelayFromPeer b -> do
L.hPut hin b
hFlush hin
loop
RelayToPeer b -> do
runner $ net $ relayToPeer (RelayToPeer b)
loop
RelayDone exitcode -> do
runner $ net $ relayToPeer (RelayDone exitcode)
return exitcode
-- Takes input from the peer, and puts it into the MVar for processing.
-- Repeats until the peer tells it it's done.
relayFeeder :: RunProto -> MVar RelayData -> IO ()
relayFeeder runner v = loop
where
loop = do
rd <- runner $ net relayFromPeer
putMVar v rd
case rd of
RelayDone _ -> return ()
_ -> loop
-- Reads input from the Handle and puts it into the MVar for relaying to
-- the peer. Continues until EOF on the Handle.
relayReader :: MVar RelayData -> Handle -> IO ()
relayReader v hout = loop
where
loop = do
bs <- getsome []
case bs of
[] -> return ()
_ -> do
putMVar v $ RelayToPeer (L.fromChunks bs)
loop
-- Waiit for the first available chunk. Then, without blocking,
-- try to get more chunks, in case a stream of chunks is being
-- written in close succession.
--
-- On Windows, hGetNonBlocking is broken, so avoid using it there.
getsome [] = do
b <- B.hGetSome hout chunk
if B.null b
then return []
#ifndef mingw32_HOST_OS
else getsome [b]
#else
else return [b]
#endif
getsome bs = do
b <- B.hGetNonBlocking hout chunk
if B.null b
then return (reverse bs)
else getsome (b:bs)
chunk = 65536
|
