Support GIT_SSH and GIT_SSH_COMMAND

They are handled close the same as they are by git. However, unlike git,
git-annex sometimes needs to pass the -n parameter when using these.

So, this has the potential for breaking some setup, and perhaps there ought
to be a ANNEX_USE_GIT_SSH=1 needed to use these. But I'd rather avoid that
if possible, so let's see if anyone complains.

Almost all places where "ssh" was run have been changed to support the env
vars. Anything still calling sshOptions does not support them. In
particular, rsync special remotes don't. Seems that annex-rsync-transport
already gives sufficient control there.

(Fixed in passing: Remote.Helper.Ssh.toRepo used to extract
remoteAnnexSshOptions and pass them to sshOptions, which was redundant
since sshOptions also extracts those.)

This commit was sponsored by Jeff Goeke-Smith on Patreon.

Remote/Bup.hs

@@ -212,11 +212,11 @@ storeBupUUID u buprepo = do
 	v = fromUUID u
 
 onBupRemote :: Git.Repo -> (FilePath -> [CommandParam] -> IO a) -> FilePath -> [CommandParam] -> Annex a
-onBupRemote r a command params = do
+onBupRemote r runner command params = do
 	c <- Annex.getRemoteGitConfig r
-	sshparams <- Ssh.toRepo NoConsumeStdin r c [Param $
-			"cd " ++ dir ++ " && " ++ unwords (command : toCommand params)]
-	liftIO $ a "ssh" sshparams
+	let remotecmd = "cd " ++ dir ++ " && " ++ unwords (command : toCommand params)
+	(sshcmd, sshparams) <- Ssh.toRepo NoConsumeStdin r c remotecmd
+	liftIO $ runner sshcmd sshparams
   where
 	path = Git.repoPath r
 	base = fromMaybe path (stripPrefix "/~/" path)

Remote/Ddar.hs

@@ -121,13 +121,12 @@ splitRemoteDdarRepo ddarrepo =
 ddarRemoteCall :: ConsumeStdin -> DdarRepo -> Char -> [CommandParam] -> Annex (String, [CommandParam])
 ddarRemoteCall cs ddarrepo cmd params
 	| ddarLocal ddarrepo = return ("ddar", localParams)
-	| otherwise = do
-		os <- sshOptions cs (host, Nothing) (ddarRepoConfig ddarrepo) []
-		return ("ssh", os ++ remoteParams)
+	| otherwise = sshCommand cs (host, Nothing) (ddarRepoConfig ddarrepo) remoteCommand
   where
 	(host, ddarrepo') = splitRemoteDdarRepo ddarrepo
 	localParams = Param [cmd] : Param (ddarRepoLocation ddarrepo) : params
-	remoteParams = Param host : Param "ddar" : Param [cmd] : Param ddarrepo' : params
+	remoteCommand = unwords $ map shellEscape $ toCommand $
+		[Param "ddar", Param [cmd], Param ddarrepo'] ++ params
 
 {- Specialized ddarRemoteCall that includes extraction command and flags -}
 ddarExtractRemoteCall :: ConsumeStdin -> DdarRepo -> Key -> Annex (String, [CommandParam])
@@ -159,23 +158,19 @@ ddarDirectoryExists ddarrepo
 			Left _ -> Right False
 			Right status -> Right $ isDirectory status
 	| otherwise = do
-		ps <- sshOptions NoConsumeStdin (host, Nothing)
-			(ddarRepoConfig ddarrepo) []
-		exitCode <- liftIO $ safeSystem "ssh" (ps ++ params)
+		let remotecmd = unwords $ map shellEscape
+			[ "test", "-d", ddarrepo' ]
+		(sshcmd, sshps) <- sshCommand NoConsumeStdin (host, Nothing)
+			(ddarRepoConfig ddarrepo) remotecmd
+		exitCode <- liftIO $ safeSystem sshcmd sshps
 		case exitCode of
 			ExitSuccess -> return $ Right True
 			ExitFailure 1 -> return $ Right False
-			ExitFailure code -> return $ Left $ "ssh call " ++
-				show (unwords $ toCommand params) ++
+			ExitFailure code -> return $ Left $ "ssh " ++
+				show (unwords $ toCommand sshps) ++
 				" failed with status " ++ show code
   where
 	(host, ddarrepo') = splitRemoteDdarRepo ddarrepo
-	params =
-		[ Param host
-		, Param "test"
-		, Param "-d"
-		, Param ddarrepo'
-		]
 
 {- Use "ddar t" to determine if a given key is present in a ddar archive -}
 inDdarManifest :: DdarRepo -> Key -> Annex (Either String Bool)

Remote/Helper/Ssh.hs

@@ -23,15 +23,10 @@ import Types.Remote
 import Types.Transfer
 import Config
 
-{- Generates parameters to ssh to a repository's host and run a command.
- - Caller is responsible for doing any neccessary shellEscaping of the
- - passed command. -}
-toRepo :: ConsumeStdin -> Git.Repo -> RemoteGitConfig -> [CommandParam] -> Annex [CommandParam]
-toRepo cs r gc sshcmd = do
-	let opts = map Param $ remoteAnnexSshOptions gc
+toRepo :: ConsumeStdin -> Git.Repo -> RemoteGitConfig -> SshCommand -> Annex (FilePath, [CommandParam])
+toRepo cs r gc remotecmd = do
 	let host = fromMaybe (giveup "bad ssh url") $ Git.Url.hostuser r
-	params <- sshOptions cs (host, Git.Url.port r) gc opts
-	return $ params ++ Param host : sshcmd
+	sshCommand cs (host, Git.Url.port r) gc remotecmd
 
 {- Generates parameters to run a git-annex-shell command on a remote
  - repository. -}
@@ -49,8 +44,7 @@ git_annex_shell cs r command params fields
 				: map shellEscape (toCommand shellopts) ++
 			uuidcheck u ++
 			map shellEscape (toCommand fieldopts)
-		sshparams <- toRepo cs r gc [Param sshcmd]
-		return $ Just ("ssh", sshparams)
+		Just <$> toRepo cs r gc sshcmd
 	| otherwise = return Nothing
   where
 	dir = Git.repoPath r

Remote/Rsync.hs

@@ -121,7 +121,6 @@ rsyncTransport gc url
 			"ssh":sshopts -> do
 				let (port, sshopts') = sshReadPort sshopts
 				    userhost = takeWhile (/=':') url
-				-- Connection caching
 				(Param "ssh":) <$> sshOptions ConsumeStdin
 					(userhost, port) gc
 					(map Param $ loginopt ++ sshopts')