1
0
Fork 0
mirror of https://github.com/moby/moby.git synced 2022-11-09 12:21:53 -05:00
Commit graph

18 commits

Author SHA1 Message Date
Alexander Larsson
24f9187a04 beam: Add simple framing system for UnixConn
This is needed for Send/Recieve to correctly handle borders between
the messages.

The framing uses a single 32bit uint32 length for each frame, of which
the high bit is used to indicate whether the message contains a file
descriptor or not. This is enough to separate out each message sent
and to decide to which message each file descriptors belongs, even
though multiple Sends may be coalesced into a single read, and/or one
Send can be split into multiple writes.

Docker-DCO-1.1-Signed-off-by: Alexander Larsson <alexl@redhat.com> (github: alexlarsson)
Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
2014-05-01 11:06:01 -07:00
Solomon Hykes
bf51f36d8f Fix Go formatting in beam and dockerscript
Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
2014-04-22 16:16:29 -07:00
Alexander Larsson
1fb0bf1b3b beam: Fix double close of fds in SendUnix
Instead of calling syscall.Close() on the fds in sendUnix() we call
Close() on the *os.File in Send(). Otherwise the fd will be closed, but
the *os.File will continue to live, and when it is finalized the
fd will be closed (which by then may be reused and can be anything).

This also adds a note to Send() the the file is closed.

Docker-DCO-1.1-Signed-off-by: Alexander Larsson <alexl@redhat.com> (github: alexlarsson)
2014-04-22 15:50:22 -07:00
Solomon Hykes
70d3262161 beam: improve the API with Sender/Receiver interfaces and utilities: Copy/SendPipe/SendPair
Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
2014-04-22 15:50:21 -07:00
Alexander Larsson
b0228d94be beam: Make extracted Fds CloseOnExec
Grab forklock to make sure no forks accidentally inherit the new fds
before they are made CLOEXEC There is a slight race condition between
ReadMsgUnix returns and when we grap the lock, so this is not
perfect. Unfortunately There is no way to pass MSG_CMSG_CLOEXEC to
recvmsg() nor any way to implement non-blocking i/o in go, so this is
hard to fix.

Docker-DCO-1.1-Signed-off-by: Alexander Larsson <alexl@redhat.com> (github: alexlarsson)
2014-04-22 15:50:21 -07:00
Solomon Hykes
bcd31405cf beam: fix FD leaks in SendPipe
This fixes file descriptor leaks in the SendPipe function.

Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
2014-04-22 15:50:18 -07:00
Solomon Hykes
1737063904 beam: more hooks for interactive debugging
This inserts low-level hooks for interactive step-by-step debugging.
Hooks are triggered by setting the *TEST* environment variable.

This is particularly useful for tracking down file descriptor leaks,
double-closing, or other issues which are difficult to debug with
the usual toolbox.

Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
2014-04-22 15:50:17 -07:00
Solomon Hykes
916372c76f Beam: remove leftover debugging messages
Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
2014-04-22 15:50:17 -07:00
Solomon Hykes
851c1b05d0 Beam: fix bug in beamsh which 'swapped' FDs because of underlying implementation of net.FileConn
Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
2014-04-22 15:50:16 -07:00
Solomon Hykes
07c03944ff Beam: don't close the attachment FD when closing superfluous FDs
Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
2014-04-22 15:50:16 -07:00
Solomon Hykes
8875cdf561 Beam: debugging hooks for easy step-by-step inspection of the FD table
Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
2014-04-22 15:50:16 -07:00
Solomon Hykes
f94a18677a Beam: Send: pass the underlying error unchanged to allow io.EOF detection
Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
2014-04-22 15:50:15 -07:00
Solomon Hykes
59853c188d Beam: USocketPair returns a *net.UnixConn socket pair for convenience.
Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
2014-04-22 15:50:15 -07:00
Solomon Hykes
c401c43cae Beam: fix file descriptor leaks
* Close all file descriptors successfully sent as attachment
* Close duplicate file descriptors created by net.FileCon and net.UnixConn.File

Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
2014-04-22 15:50:15 -07:00
Solomon Hykes
b637e5f04a Beam: change the prototype of SendPipe() to return a *net.UnixSocket
Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
2014-04-22 15:50:14 -07:00
Solomon Hykes
188c2ef806 Beam: allow sending messages without attachments.
Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
2014-04-22 15:50:14 -07:00
Solomon Hykes
3960da04c8 Beam: convenience functions Listen and Connect
These convenience functions expose a familiar face to the unknown and bizarre world of beam networking.

Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
2014-04-22 15:50:14 -07:00
Solomon Hykes
5957e6b385 Beam: a simple stream-oriented communication protocol for distributed systems.
This patch includes a stripped down implementation with a bare minimum
unix socket transport. It relies on fd passing for stream multiplexing.

The purpose of this first patch is to allow implementation of dynamic
linking, which will allow advanced service discovery.

Docker-DCO-1.1-Signed-off-by: Solomon Hykes <solomon@docker.com> (github: shykes)
2014-04-22 15:50:14 -07:00