Fix a race condition when asking a client to take over the terminal (switching
to a different poll loop):
If a MSG_READY was followed very quickly by a MSG_EXIT (for example if doing
"tmux new 'exit'"), both messages could be read as part of the same imsg_read
in the first client poll loop. The MSG_READY would then cause a switch to the
second client loop, which would immediately call poll(2) again, causing the
client to hang forever waiting for an exit message that it already had.
Change to call imsg_get to process any existing messages before polling.
use the error and exit on MSG_EXIT (it was being handled in the default
case). Undo the last change, move the errstr check into the MSG_EXIT case, and
add a comment.
imsg closes the fd after sending, so dup() STDIN_FILENO before passing it to
the parent, otherwise TIOCGWINSZ will fail when the window is resized (that
could actually be moved into the server but this is more future-proof and
avoids breaking the protocol).
Have the client pass its stdin fd to the server when identifying itself and
have the server use that rather than reopening the tty. If the fd isn't given,
use the old behaviour (so no need for a version change).
This allows tmux to be used as the shell, so also change so that when working
out the command to execute if default-command is empty (the default), tmux will
try not execute itself.
Switch tmux to use imsg. This is the last major change to make the
client-server protocol more resilient and make the protocol versioning work
properly. In future, the only things requiring a protocol version bump will be
changes in the message structs, and (when both client and server have this
change) mixing different versions should nicely report an error message.
As a side effect this also makes the code tidier, fixes a problem with the way
errors reported during server startup were handled, and supports fd passing
(which will be used in future).
Looked over by eric@, thanks.
Please note that mixing a client with this change with an older server or vice
versa may cause tmux to crash or hang - tmux should be completely exited before
upgrading.
Infrastructure and commands to manage the environment for processes started
within tmux.
There is a global environment, copied from the external environment when the
server is started and each session has an (initially empty) session
environment which overrides it.
New commands set-environment and show-environment manipulate or display the
environments.
A new session option, update-environment, is a space-separated list of
variables which are updated from the external environment into the session
environment every time a new session is created - the default is DISPLAY.
There aren't many client message types or code to handle them so get rid of
the lookup table and use a switch, merge the tiny handler functions into it,
and move the whole lot to client.c.
Also change client_msg_dispatch to consume as many messages as possible and
move the call to it to the right place so it checks for signals afterwards.
Prompted by suggestions from eric@.
Make all messages sent between the client and server fixed size.
This is the first of two changes to make the protocol more resilient and less
sensitive to other changes in the code, particularly with commands. The client
now packs argv into a buffer and sends it to the server for parsing, rather
than doing it itself and sending the parsed command data.
As a side-effect this also removes a lot of now-unused command marshalling
code.
Mixing a server without this change and a client with or vice versa will cause
tmux to hang or crash, please ensure that tmux is entirely killed before
upgrading.
done for UTF-8, limit to the maximum length correctly when printing, and always
print a space even if the left string is longer than the width available.
script which must be run before building.
Still two makefiles but they are a hell of a lot simpler.
HAVE_* also will make it easier to move to $buildsystem if necessary later.
