If a background process runs a fish function which launches another
background process, ensure that these background procs get different
pgroups. Add a test for it.
Which happened when starting the selection at the end of the commandline.
In this case, selections still interact weirdly with autosuggestions (the
first character of the suggestion appears to be part of the selection
when it's not).
Fixes#6680
Prior to this commit, when executing a builtin, we mark the job as not
foreground. After this commit we no longer modify the foreground state
of the job just for the builtin.
There was the following comment:
// Since this may be the foreground job, and since a builtin may execute another
// foreground job, we need to pretend to suspend this job while running the
// builtin, in order to avoid a situation where two jobs are running at once.
The concern seemed to be in the `bg` and `fg` builtins, which might attempt
to foreground or background the jobs associated with `bg` and `fg` themselves.
But the builtins run before the job is marked constructed, so it cannot
actually happen.
Bravely remove this code.
Mostly line breaks, one instance of tabs!
For some reason clang-format insists on two spaces before a same-line comment?
(I continue to be unimpressed with super-strict line length limits,
but I continue to believe in automatic styling, so it is what it is)
[ci skip]
It used to error out when a command wasn't known, even when it was a
function that would only be discovered via autoloading.
Now we just accept that a command doesn't exist when no-execute is
given - we're not gonna execute it anyway.
Also, in the same breath stop counting empty commands after expansion
and empty wildcard expansions as errors - these depend on runtime
values, so we can't verify them without executing.
Fixes#977.
(note that it still executes "time", but that's another commit)
Appending to an fd doesn't really make sense, but we allowed the
syntax previously and it was actually used.
It's not too harmful to allow it, so let's just do that again.
For the record: Zsh also allows it, bash doesn't.
Fixes#6614
When building fish-shell with the macOS 10.12 SDK, <sys/proc.h> does not
include <sys/time.h> but references `struct itimerval`. This causes a
compilation failure if we don't import <sys/time.h> ourselves.
This was previously masked by an import of <sys/sysctl.h>, which was
removed in fc0c39b6fd.
Glob ordering is used in a variety of places, including figuring out
conf.d and really needs to be stable.
Other ordering, like completions, is really just cosmetic and can
change if it makes for a nicer experience.
So we uncouple it by copying the wcsfilecmp from 3.0.2, which will
return the ordering to what it was in that release.
Fixes#6593
The `function --on-job-exit caller` feature allows a command substitution
to observe when the parent job exits. This has never worked very well - in
particular it is based on job IDs, so a function that observes this will
run multiple times. Implement it properly.
Do this by having a not-recycled "internal job id".
This is only used by psub, but ensure it works properly none-the-less.
"job_exit" events, despite their name, can only be created via
the '--on-job-exit caller' misfeature of function. Rename it to make it
clear that this event type is specifically for caller-exit.
Add the input function undo which is bound to `\c_` (control + / on
some terminals). Redoing the most recent chain of undos is supported,
redo is bound to `\e/` for now.
Closes#1367.
This approach should not have the issues discussed in #5897.
Every single modification to the commandline can be undone individually,
except for adjacent single-character inserts, which are coalesced,
so they can be reverted with a single undo. Coalescing is not done for
space characters, so each word can be undone separately.
When moving between history search entries, only the current history
search entry is reachable via the undo history. This allows to go back
to the original search string with a single undo, or by pressing the
escape key.
Similarly, when moving between pager entries, only the most recent
selection in the pager can be undone.
This switches bufferfills from using an exclusively-owned thread, to
sharing an fd_monitor. This allows multiple bufferfills to all use the same
thread.
fd_monitor is a new class which can monitor a set of fds, waiting for them
to become readable. When an fd becomes readable, a callback is invoked.
Timeouts are also supported.
This is intended to replace the "bufferfill" threads. Rather than one
thread per bufferfill, we will have a single fd_monitor which can service
multiple bufferfills. This helps today with nested command substitutions,
and will help in the future with concurrent execution.
This makes two changes:
1. Remove the 'brace_text_start' idea. The idea of 'brace_text_start' was
to prevent emitting `BRACE_SPACE` at the beginning or end of an item. But
we later strip these off anyways, so there is no apparent benefit. If we
are not doing brace expansion, this prevented emitting whitespace at the
beginning or end of an item, leading to #6564.
2. When performing brace expansion, only stomp the space character with
`BRACE_SPACE`; do not stomp newlines and tabs. This is because the fix in
came from a newline or tab literal, then we would have effectively
replaced a newline or tab with a space, so this is important for #6564 as
well. Moreover, it is not easy to place a literal newline or tab inside a
brace expansion, and users who do probably do not mean for it to be
stripped, so I believe this is a good change in general.
Fixes#6564
fish has some unprincipled code that attempts to tcsetpgrp() to own the
terminal before running a builtin; this was added because 'read' might
want to read from the terminal. I added this code before fully
understanding how process groups and terminals work. A better fix would
be to ensure that fish is marked as the pgroup leader in the job when
the builtin is the first process in the job, and we do that now.
Courageously back out the changes to grab the terminal; see #5147 and
also #5133.
Introduce pgroup_provenance_t, a type which captures "where the pgroup
comes from." This centralizes some logic around how pgroups are
assigned, and it anticipates concurrent execution.
In some cases on some platforms this could clobber errno, so doing something like
aThingThatFailsWithErrno();
FLOG(category, "Some message");
wperror("something");
would print the wrong error (presumably if that category was enabled).
In our case it was our (very) old friend RHEL6 returning ESPIPE instead of EISDIR.
Fixes#6545.
Prior to this fix, the cancellation C++ test would mark the parser as
interactive in an effort to install interactive signal handling (so that,
for example, SIGINT would stop the job and return control to the user).
However this flag would also cause fish to attempt to save and restore tty modes
across the job. This would fail since there is no tty, and so the job would fail
with an unexpected error code.
We don't need to mark the parser as interactive, we can just remove that line.
Fixes#6539.
Use some more move semantics to reduce allocations.
Correctly handle the case where the completion is empty. For example, if
you type:
ls<tab>
we get an empty completion (since ls is already a valid command), but we
still want to show its description.
Remove some unsafe statics - these are unsafe today in weird cases where
completions might invoke complete recursively, and also will soon be
unsafe with concurrent execution.
Prior to this fix, fish was rather inconsistent in when $status gets set
in response to an error. For example, a failed expansion like "$foo["
would not modify $status.
This makes the following inter-related changes:
1. String expansion now directly returns the value to set for $status on
error. The value is always used.
2. parser_t::eval() now directly returns the proc_status_t, which cleans
up a lot of call sites.
3. We expose a new function exec_subshell_for_expand() which ignores
$status but returns errors specifically related to subshell expansion.
4. We reify the notion of "expansion breaking" errors. These include
command-not-found, expand syntax errors, and others.
The upshot is we are more consistent about always setting $status on
errors.
Sometimes we must spawn a new thread, to avoid the risk of deadlock.
Ensure we always spawn a thread in those cases. In particular this
includes the fillthread.
complete -C'echo $HOM ' would complete $HOM instead of a new token.
Fixes another regression introduced in
6fb7f9b6b - Fix completion for builtins with subcommands
64 is too low (it's actually reachable), and every sensible system should have a limit above
this.
On OpenBSD and FreeBSD it's ULONG_MAX, on my linux system it's 61990.
Plus we currently fail by hanging if our limit is reached, so this
should improve things regardless.
On my linux system _POSIX_THREAD_THREADS_MAX works out to 64 here,
which is just too low, even tho the system can handle more.
Fixes#6503 harder.
This commit recognizes an existing pattern: many operations need some
combination of a set of variables, a way to detect cancellation, and
sometimes a parser. For example, tab completion needs a parser to execute
custom completions, the variable set, should cancel on SIGINT. Background
autosuggestions don't need a parser, but they do need the variables and
should cancel if the user types something new. Etc.
This introduces a new triple operation_context_t that wraps these concepts
up. This simplifies many method signatures and argument passing.
When executing a buffered block or builtin, the usual approach is to
execute, collect output in a string, and then output that string to
stdout or whatever the redirections say. Similarly for stderr.
If we get no output, then we can elide the outputting which means
skipping the background thread. In this case we just mark the process as
finished immediately.
We do this in multiple locations which is confusing. Factor them all
together into a new function run_internal_process_or_short_circuit.
for-loops that were not inside a function could overwrite global
and universal variables with the loop variable. Avoid this by making
for-loop-variables local variables in their enclosing scope.
This means that if someone does:
set a global
for a in local; end
echo $a
The local $a will shadow the global one (but not be visible in child
scopes). Which is surprising, but less dangerous than the previous
behavior.
The detection whether the loop is running inside a function was failing
inside command substitutions. Remove this special handling of functions
alltogether, it's not needed anymore.
Fixes#6480
'fish_test_helper print_pid_then_sleep' tried to sleep for .5 seconds,
but instead it divided by .5 so it actually slept for 2 seconds.
This exceeds the maximum value on NetBSD so it wasn't sleeping at all
there.
Fixes#6476
Empty items are used as sentinels to indicate that we've reached the end of
history, so they should not be added as actual items. Enforce this.
Fixes#6032
This reduces the syscall count for `fish -c exit` from 651 to 566.
We don't attempt to *cache* the pgrp or anything, we just call it once
when we're about to execute the job to see if we are in foreground and
to assign it to the job, instead of once for checking foreground and
once to give it to the job.
Caching it with a simple `static` would get the count down to 480, but
it's possible for fish to have its pgroup changed.
Store the entire function declaration, not just its job list.
This allows us to extract the body of the function complete with any
leading comments and indents.
Fixes#5285
In particular, this allows `true && time true`, or `true; and time true`,
and both `time not true` as well as `not time true` (like bash).
time is valid only as job _prefix_, so `true | time true` could call
`/bin/time` (same in bash)
See discussion in #6442
Extend the commit 8e17d29e04 to block processes, for example:
begin ; stuff ; end
or if/while blocks as well.
Note there's an existing optimization where we do not create a job for a
block if it has no redirections.
job_promote attempts to bring the most recently "touched" job to the front
of the job list. It did this via:
std::rotate(begin, job, end)
However this has the effect of pushing job-1 to the end. That is,
promoting '2' in [1, 2, 3] would result in [2, 3, 1].
Correct this by replacing it with:
std::rotate(begin, job, job+1);
now we get the desired [2, 1, 3].
Also add a test.
This PR is aimed at improving how job ids are assigned. In particular,
previous to this commit, a job id would be consumed by functions (and
thus aliases). Since it's usual to use functions as command wrappers
this results in awkward job id assignments.
For example if the user is like me and just made the jump from vim -> neovim
then the user might create the following alias:
```
alias vim=nvim
```
Previous to this commit if the user ran `vim` after setting up this
alias, backgrounded (^Z) and ran `jobs` then the output might be:
```
Job Group State Command
2 60267 stopped nvim $argv
```
If the user subsequently opened another vim (nvim) session, backgrounded
and ran jobs then they might see what follows:
```
Job Group State Command
4 70542 stopped nvim $argv
2 60267 stopped nvim $argv
```
These job ids feel unnatural, especially when transitioning away from
e.g. bash where job ids are sequentially incremented (and aliases/functions
don't consume a job id).
See #6053 for more details.
As @ridiculousfish pointed out in
https://github.com/fish-shell/fish-shell/issues/6053#issuecomment-559899400,
we want to elide a job's job id if it corresponds to a single function in the
foreground. This translates to the following prerequisites:
- A job must correspond to a single process (i.e. the job continuation
must be empty)
- A job must be in the foreground (i.e. `&` wasn't appended)
- The job's single process must resolve to a function invocation
If all of these conditions are true then we should mark a job as
"internal" and somehow remove it from consideration when any
infrastructure tries to interact with jobs / job ids.
I saw two paths to implement these requirements:
- At the time of job creation calculate whether or not a job is
"internal" and use a separate list of job ids to track their ids.
Additionally introduce a new flag denoting that a job is internal so
that e.g. `jobs` doesn't list internal jobs
- I started implementing this route but quickly realized I was
computing the same information that would be computed later on (e.g.
"is this job a single process" and "is this jobs statement a
function"). Specifically I was computing data that populate_job_process
would end up computing later anyway. Additionally this added some
weird complexities to the job system (after the change there were two
job id lists AND an additional flag that had to be taken into
consideration)
- Once a function is about to be executed we release the current jobs
job id if the prerequisites are satisfied (which at this point have
been fully computed).
- I opted for this solution since it seems cleaner. In this
implementation "releasing a job id" is done by both calling
`release_job_id` and by marking the internal job_id member variable to
-1. The former operation allows subsequent child jobs to reuse that
same job id (so e.g. the situation described in Motivation doesn't
occur), and the latter ensures that no other job / job id
infrastructure will interact with these jobs because valid jobs have
positive job ids. The second operation causes job_id to become
non-const which leads to the list of code changes outside of `exec.c`
(i.e. a codemod from `job_t::job_id` -> `job_t::job_id()` and moving the
old member variable to a non-const private `job_t::job_id_`)
Note: Its very possible I missed something and setting the job id to -1
will break some other infrastructure, please let me know if so!
I tried to run `make/ninja lint`, but a bunch of non-relevant issues
appeared (e.g. `fatal error: 'config.h' file not found`). I did
successfully clang-format (`git clang-format -f`) and run tests, though.
This PR closes#6053.
It looks like the last status already contains the signal that cancelled
execution.
Also make `fish -c something` always return the last exit status of
"something", instead of hardcoded 127 if exited or signalled.
Fixes#6444
Previously, the block stack was a true stack. However in most cases, you
want to traverse the stack from the topmost frame down. This is awkward
to do with range-based for loops.
Switch it to pushing new blocks to the front of the block list.
This simplifies some traversals.
This was previously required so that, if there was a redirection to a
file, we would fork a process to create the file even if there was no
output. For example `echo -n >/tmp/file.txt` would have to create
file.txt even though it would be empty.
However now we open the file before fork, so we no longer need special
logic around this.
Do this only when splitting on IFS characters which usually contains
whitespace characters --- read --delimiter is unchanged; it still
consumes no more than one delimiter per variable. This seems better,
because it allows arbitrary delimiters in the last field.
Fixes#6406
user_supplied was used to distinguish IO redirections which were
explicit, vs those that came about through "transmogrphication." But
transmogrification is no more. Remove the flag.
As of GCC 7.4 (at least under macOS 10.10), the previous workaround of
casting a must-use result to `(void)` to avoid warnings about unused
code no longer works.
This workaround is uglier but it quiets these warnings.
The C++ spec (as of C++17/n4713) does not specify the sign of `wchar_t`,
saying only (in section 6.7.1: Fundamental Types)
> Type wchar_t shall have the same size, signedness, and alignment
> requirements (6.6.5) as one of the other integral types, called its
> underlying type.
On most *nix platforms on AMD64 architecture, `wchar_t` is a signed type
and can be compared with `int32_t` without incident, but on at least
some platforms (tested: clang under FreeBSD 12.1 on AARCH64), `wchar_t`
appears to be unsigned leading to sign comparison warnings:
```
../src/widecharwidth/widechar_width.h:512:48: warning: comparison of
integers of different signs: 'const wchar_t' and 'int32_t' (aka 'int')
[-Wsign-compare]
return where != std::end(arr) && where->lo <= c;
```
This patch forces the use of wchar_t for the range start/end values in
`widechar_range` and the associated comparison values.
Previously, if the user control-C'd out of a process, we would set a
bogus exit status in the process, but it was difficult to observe this
because we would be cancelling anyways. But set it properly.
If a Control-C is received during expanding a command substitution, we
may execute the job anyways, because we do not check for cancellation
after the expansion. Ensure that does not happen.
This should fix sporadic test failures in the cancellation unit test.
parser_t::eval indicates whether there was a parse error. It can be
easily confused with the status of the execution. Use a real type to
make it more clear.
Looking up a variable by a string literal implicitly constructs a wcstring.
By avoiding that, we get a noticeable reduction of temporary allocations.
$ HOME=. heaptrack ./fish -c true
heaptrack stats: # baseline
allocations: 7635
leaked allocations: 3277
temporary allocations: 602
heaptrack stats: # new
allocations: 7565
leaked allocations: 3267
temporary allocations: 530
This adds a test for the obscure case where an fd is redirected to
itself. This is tricky because the dup2 will not clear the CLO_EXEC bit.
So do it manually; also posix_spawn can't be used in this case.
The IO cleanup left file redirections open in the child. For example,
/bin/cmd < file.txt would redirect stdin but also leave the file open.
Ensure these get closed properly.
Prior to this fix, a file redirection was turned into an io_file_t. This is
annoying because every place where we want to apply the redirection, we
might fail due to open() failing. Switch to opening the file at the point
we resolve the redirection spec. This will simplify a lot of code.
Prior to this change, a process after it has been constructed by
parse_execution, but before it is executed, was given a list of
io_data_t redirections. The problem is that redirections have a
sensitive ownership policy because they hold onto fds. This made it
rather hard to reason about fd lifetime.
Change these to redirection_spec_t. This is a textual description
of a redirection after expansion. It does not represent an open file and
so its lifetime is no longer important.
This enables files to be held only on the stack, and are no longer owned
by a process of indeterminate lifetime.
fish has to ensure that the pipes it creates do not conflict with any
explicit fds named in redirections. Switch this code to using
autoclose_fd_t to make the ownership logic more explicit, and also
introduce fd_set_t to reduce the dependence on io_chain_t.
Prior to this fix, a job would hold onto any IO redirections from its
parent. For example:
begin
echo a
end < file.txt
The "echo a" job would hold a reference to the I/O redirection.
The problem is that jobs then extend the life of pipes until the job is
cleaned up. This can prevent pipes from closing, leading to hangs.
Fix this by not storing the block IO; this ensures that jobs do not
prolong the life of pipes.
Fixes#6397
Currently a job needs to know three things about its "parents:"
1. Any IO redirections for the block or function containing this job
2. The pgid for the parent job
3. Whether the parent job has been fully constructed (to defer self-disown)
These are all tracked in somewhat separate awkward ways. Collapse them
into a single new type job_lineage_t.
