Merge branch 'il/remote-fd-ext'

* il/remote-fd-ext:
  remote-fd/ext: finishing touches after code review
  git-remote-ext
  git-remote-fd
  Add bidirectional_transfer_loop()

Conflicts:
	compat/mingw.h

.gitignore

@@ -112,6 +112,8 @@
 /git-remote-https
 /git-remote-ftp
 /git-remote-ftps
+/git-remote-fd
+/git-remote-ext
 /git-remote-testgit
 /git-repack
 /git-replace

Documentation/git-remote-ext.txt

@@ -0,0 +1,125 @@
+git-remote-ext(1)
+=================
+
+NAME
+----
+git-remote-ext - Bridge smart transport to external command.
+
+SYNOPSIS
+--------
+git remote add nick "ext::<command>[ <arguments>...]"
+
+DESCRIPTION
+-----------
+This remote helper uses the specified 'program' to connect
+to a remote git server.
+
+Data written to stdin of this specified 'program' is assumed
+to be sent to git:// server, git-upload-pack, git-receive-pack
+or git-upload-archive (depending on situation), and data read
+from stdout of this program is assumed to be received from
+the same service.
+
+Command and arguments are separated by unescaped space.
+
+The following sequences have a special meaning:
+
+'% '::
+	Literal space in command or argument.
+
+'%%'::
+	Literal percent sign.
+
+'%s'::
+	Replaced with name (receive-pack, upload-pack, or
+	upload-archive) of the service git wants to invoke.
+
+'%S'::
+	Replaced with long name (git-receive-pack,
+	git-upload-pack, or git-upload-archive) of the service
+	git wants to invoke.
+
+'%G' (must be first characters in argument)::
+	This argument will not be passed to 'program'. Instead, it
+	will cause helper to start by sending git:// service request to
+	remote side with service field set to approiate value and
+	repository field set to rest of the argument. Default is not to send
+	such request.
++
+This is useful if remote side is git:// server accessed over
+some tunnel.
+
+'%V' (must be first characters in argument)::
+	This argument will not be passed to 'program'. Instead it sets
+	the vhost field in git:// service request (to rest of the argument).
+	Default is not to send vhost in such request (if sent).
+
+ENVIRONMENT VARIABLES:
+----------------------
+
+GIT_TRANSLOOP_DEBUG::
+	If set, prints debugging information about various reads/writes.
+
+ENVIRONMENT VARIABLES PASSED TO COMMAND:
+----------------------------------------
+
+GIT_EXT_SERVICE::
+	Set to long name (git-upload-pack, etc...) of service helper needs
+	to invoke.
+
+GIT_EXT_SERVICE_NOPREFIX::
+	Set to long name (upload-pack, etc...) of service helper needs
+	to invoke.
+
+
+EXAMPLES:
+---------
+This remote helper is transparently used by git when
+you use commands such as "git fetch <URL>", "git clone <URL>",
+, "git push <URL>" or "git remote add nick <URL>", where <URL>
+begins with `ext::`.  Examples:
+
+"ext::ssh -i /home/foo/.ssh/somekey user&#64;host.example %S 'foo/repo'"::
+	Like host.example:foo/repo, but use /home/foo/.ssh/somekey as
+	keypair and user as user on remote side. This avoids needing to
+	edit .ssh/config.
+
+"ext::socat -t3600 - ABSTRACT-CONNECT:/git-server %G/somerepo"::
+	Represents repository with path /somerepo accessable over
+	git protocol at abstract namespace address /git-server.
+
+"ext::git-server-alias foo %G/repo"::
+	Represents a repository with path /repo accessed using the
+	helper program "git-server-alias foo".  The path to the
+	repository and type of request are not passed on the command
+	line but as part of the protocol stream, as usual with git://
+	protocol.
+
+"ext::git-server-alias foo %G/repo %Vfoo"::
+	Represents a repository with path /repo accessed using the
+	helper program "git-server-alias foo".  The hostname for the
+	remote server passed in the protocol stream will be "foo"
+	(this allows multiple virtual git servers to share a
+	link-level address).
+
+"ext::git-server-alias foo %G/repo% with% spaces %Vfoo"::
+	Represents a repository with path '/repo with spaces' accessed
+	using the helper program "git-server-alias foo".  The hostname for
+	the remote server passed in the protocol stream will be "foo"
+	(this allows multiple virtual git servers to share a
+	link-level address).
+
+"ext::git-ssl foo.example /bar"::
+	Represents a repository accessed using the helper program
+	"git-ssl foo.example /bar".  The type of request can be
+	determined by the helper using environment variables (see
+	above).
+
+Documentation
+--------------
+Documentation by Ilari Liusvaara, Jonathan Nieder and the git list
+<[email protected]>
+
+GIT
+---
+Part of the linkgit:git[1] suite

Documentation/git-remote-fd.txt

@@ -0,0 +1,59 @@
+git-remote-fd(1)
+================
+
+NAME
+----
+git-remote-fd - Reflect smart transport stream back to caller
+
+SYNOPSIS
+--------
+"fd::<infd>[,<outfd>][/<anything>]" (as URL)
+
+DESCRIPTION
+-----------
+This helper uses specified file descriptors to connect to remote git server.
+This is not meant for end users but for programs and scripts calling git
+fetch, push or archive.
+
+If only <infd> is given, it is assumed to be bidirectional socket connected
+to remote git server (git-upload-pack, git-receive-pack or
+git-upload-achive). If both <infd> and <outfd> are given, they are assumed
+to be pipes connected to remote git server (<infd> being the inbound pipe
+and <outfd> being the outbound pipe.
+
+It is assumed that any handshaking procedures have already been completed
+(such as sending service request for git://) before this helper is started.
+
+<anything> can be any string. It is ignored. It is meant for provoding
+information to user in the URL in case that URL is displayed in some
+context.
+
+ENVIRONMENT VARIABLES
+---------------------
+GIT_TRANSLOOP_DEBUG::
+	If set, prints debugging information about various reads/writes.
+
+EXAMPLES
+--------
+git fetch fd::17 master::
+	Fetch master, using file descriptor #17 to communicate with
+	git-upload-pack.
+
+git fetch fd::17/foo master::
+	Same as above.
+
+git push fd::7,8 master (as URL)::
+	Push master, using file descriptor #7 to read data from
+	git-receive-pack and file descriptor #8 to write data to
+	same service.
+
+git push fd::7,8/bar master::
+	Same as above.
+
+Documentation
+--------------
+Documentation by Ilari Liusvaara and the git list <[email protected]>
+
+GIT
+---
+Part of the linkgit:git[1] suite

Makefile

@@ -739,6 +739,8 @@ BUILTIN_OBJS += builtin/read-tree.o
 BUILTIN_OBJS += builtin/receive-pack.o
 BUILTIN_OBJS += builtin/reflog.o
 BUILTIN_OBJS += builtin/remote.o
+BUILTIN_OBJS += builtin/remote-ext.o
+BUILTIN_OBJS += builtin/remote-fd.o
 BUILTIN_OBJS += builtin/replace.o
 BUILTIN_OBJS += builtin/rerere.o
 BUILTIN_OBJS += builtin/reset.o

builtin.h

@@ -108,6 +108,8 @@ extern int cmd_read_tree(int argc, const char **argv, const char *prefix);
 extern int cmd_receive_pack(int argc, const char **argv, const char *prefix);
 extern int cmd_reflog(int argc, const char **argv, const char *prefix);
 extern int cmd_remote(int argc, const char **argv, const char *prefix);
+extern int cmd_remote_ext(int argc, const char **argv, const char *prefix);
+extern int cmd_remote_fd(int argc, const char **argv, const char *prefix);
 extern int cmd_config(int argc, const char **argv, const char *prefix);
 extern int cmd_rerere(int argc, const char **argv, const char *prefix);
 extern int cmd_reset(int argc, const char **argv, const char *prefix);