This adds support for `fish_trace`, a new variable intended to serve the
same purpose as `set -x` as in bash. Setting this variable to anything
non-empty causes execution to be traced. In the future we may give more
specific meaning to the value of the variable.
The user's prompt is not traced unless you run it explicitly. Events are
also not traced because it is noisy; however autoloading is.
Fixes#3427
Soon we will have more complicated logic around whether to call tcsetpgrp.
Prepare to centralize the logic by passing in the new term owner pgrp,
instead of having child_setup_process perform the decision.
When executing a job, if the first process is fish internal, then have
fish claim the job's pgroup.
The idea here is that the terminal must be owned by a pgroup containing
the process reading from the terminal. If the first process is fish
internal (a function or builtin) then the pgroup must contain the fish
process.
This is a bit of a workaround of the behavior where the first process that
executes in a job becomes the process group leader. If there's a deferred
process, then we will execute processes out of order so the pgroup can be
wrong. Fix this by setting the process group leader explicitly as fish
when necessary.
Fixes#5855
25afc9b377 made this unnecessary by
having child processes wait for a signal after fork(), but this change
was later reverted. If we artificially slow down fish (e.g. with a sleep)
after the fork call, we see commands getting backgrounded by mistake.
Put back the tcsetgrp() call.
Prior to this fix, a function_block stored a process_t, which was only used
when printing backtraces. Switch this to an array of arguments, and make
various other cleanups around null terminated argument arrays.
This runs build_tools/style.fish, which runs clang-format on C++, fish_indent on fish and (new) black on python.
If anything is wrong with the formatting, we should fix the tools, but automated formatting is worth it.
Prior to this change, fish used a global flag to decide if we should check
for changes to universal variables. This flag was then checked at arbitrary
locations, potentially triggering variable updates and event handlers for
those updates; this was very hard to reason about.
Switch to triggering a universal variable update at a fixed location,
after running an external command. The common case is that the variable
file has not changed, which we can identify with just a stat() call, so
this is pretty cheap.
This reverts commit cdce8511a1.
This change was unsafe. The prior version (now restored) took the lock and
then copied the data. By returning a reference, the caller holds a
reference to data outside of the lock.
This function isn't worth optimizing. Hardly any functions use this
facility, and for those that do, they typically just capture one or two
variables.
