These stack traces kind of suck for the reasons mentioned on the
CppTrace page here (no symbols for inline functions is a major one):
https://github.com/jeremy-rifkin/cpptrace
I would consider using CppTrace if it were packaged, but to be honest, I
think that the more reasonable option is actually to move entirely to
out-of-process crash handling and symbolization.
The reason for this is that if you want to generate anything of
substance on SIGSEGV or really any deadly signal, you are stuck in
async-signal-safe land, which is not a place to be trying to run a
symbolizer. LLVM does it anyway, probably carefully, and chromium *can*
do it on debug builds but in general uses crashpad:
https://source.chromium.org/chromium/chromium/src/+/main:base/debug/stack_trace_posix.cc;l=974;drc=82dff63dbf9db05e9274e11d9128af7b9f51ceaa;bpv=1;bpt=1
However, some stack traces are better than *no* stack traces when we get
mystery exceptions falling out the bottom of the program. I've also
promoted the path for "mystery exceptions falling out the bottom of the
program" to hard crash and generate a core dump because although there's
been some months since the last one of these, these are nonetheless
always *atrociously* diagnosed.
We can't improve the crash handling further until either we use Crashpad
(which involves more C++ deps, no thanks) or we put in the ostensibly
work in progress Rust minidump infrastructure, in which case we need to
finish full support for Rust in libutil first.
Sample report:
Lix crashed. This is a bug. We would appreciate if you report it at https://git.lix.systems/lix-project/lix/issues with the following information included:
Exception: std::runtime_error: lol
Stack trace:
0# nix::printStackTrace() in /home/jade/lix/lix3/build/src/nix/../libutil/liblixutil.so
1# 0x000073C9862331F2 in /home/jade/lix/lix3/build/src/nix/../libmain/liblixmain.so
2# 0x000073C985F2E21A in /nix/store/p44qan69linp3ii0xrviypsw2j4qdcp2-gcc-13.2.0-lib/lib/libstdc++.so.6
3# 0x000073C985F2E285 in /nix/store/p44qan69linp3ii0xrviypsw2j4qdcp2-gcc-13.2.0-lib/lib/libstdc++.so.6
4# nix::handleExceptions(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::function<void ()>) in /home/jade/lix/lix3/build/src/nix/../libmain/liblixmain.so
5# 0x00005CF65B6B048B in /home/jade/lix/lix3/build/src/nix/nix
6# 0x000073C985C8810E in /nix/store/dbcw19dshdwnxdv5q2g6wldj6syyvq7l-glibc-2.39-52/lib/libc.so.6
7# __libc_start_main in /nix/store/dbcw19dshdwnxdv5q2g6wldj6syyvq7l-glibc-2.39-52/lib/libc.so.6
8# 0x00005CF65B610335 in /home/jade/lix/lix3/build/src/nix/nix
Change-Id: I1a9f6d349b617fd7145a37159b78ecb9382cb4e9
This caused an infinite loop before since it would just keep asking the
underlying source for more data.
In practice this happened because an HTTP server served a
response to a HEAD request (for which curl will not retrieve any body or
call our write callback function) with Content-Encoding: br, leading to
decompressing nothing at all and going into an infinite loop.
This adds a test to make sure none of our compression methods do that
again, as well as just patching the HTTP client to never feed empty data
into a compression algorithm (since they absolutely have the right to
throw CompressionError on unexpectedly-short streams!).
Reported on Matrix: https://matrix.to/#/!lymvtcwDJ7ZA9Npq:lix.systems/$8BWQR_zKxCQDJ40C5NnDo4bQPId3pZ_aoDj2ANP7Itc?via=lix.systems&via=matrix.org&via=tchncs.de
Change-Id: I027566e280f0f569fdb8df40e5ecbf46c211dad1
The legitimate output of `nix path-info` may visually interfere with the
progress bar, by appending to stale progress output before the latter has been
erased. Conveniently, all expensive operations (evaluation or building) have
already been performed before, so we can simply wipe the progress bar at this
point to fix the issue.
Fixes: #343
Change-Id: Id9a807a5c882295b3e6fbf841f9c15dc96f67f6e
This test suite was in desperate need of using the parameterization
available with gtest, and was a bunch of useless duplicated code. At
least now it's not duplicated code, though it still probably should be
more full of property tests.
Change-Id: Ia8ccee7ef4f02b2fa40417b79aa8c8f0626ea479
See #496.
The core idea is to be able to do e.g.
nix-instantiate -A some-nonfree-thing --arg config.allowUnfree true
which is currently not possible since `config.allowUnfree` is
interpreted as attribute name with a dot in it.
In order to change that (probably), Jade suggested to find out if there
are any folks out there relying on this behavior.
For such a use-case, it may still be possible to accept strings, i.e.
`--arg '"config.allowUnfree"'.
Change-Id: I986c73619fbd87a95b55e2f0ac03feaed3de2d2d
Apparently forgejo has a more creative interpretation of \(\) than I was
hoping in their markdown parser and thought it was maths. I have no idea
then how you put a link in parens next to another square-bracket link,
but I am not going to worry about it.
There were several more typos, which I also fixed.
Fixes: #517
Change-Id: I6b144c6881f92ca60ba72a304ce7a0bcb9c6659a
* Move the extended attribute deletion after the hardlink sanity check. We
shouldn't be removing extended attributes on random files.
* Make the entity owner-writable before attempting to remove extended
attributes, since this operation usually requires write access on the file,
and we shouldn't fail xattr deletion on a file that has been made unwritable
by the builder or a previous canonicalisation pass.
Fixes: #507
Change-Id: I7e6ccb71649185764cd5210f4a4794ee174afea6
Remove the mutable state stuff that assumes that one file is being
written a time. It's true that we don't write multiple files
interleaved, but that mutable state is evil.
Change-Id: Ia1481da48255d901e4b09a9b783e7af44fae8cff
When generating shell completions, no logging output should be visible because
it would destroy the shell prompt. Originally this was attempted to be done by
simply disabling the progress bar (ca946860ce),
since the situation is particularly bad there (the screen clearing required for
the rendering ends up erasing the shell prompt). Due to overlooking the
implementation of this hack, it was accidentally undone during a later change
(0dd1d8ca1c).
Since even with the hack correctly in place, it is still possible to mess up
the prompt by logging output (for example warnings for disabled experimental
features, or messages generated by `builtins.trace`), simply send it to the bit
bucket where it belongs. This was already done for bash and zsh
(9d840758a8), and it seems that fish was simply
missed at that time. The last trace of the no-longer-working and obsolete hack
is deleted too.
Fixes: #513
Change-Id: I59f1ebf90903034e2059298fa8d76bf970bc3315
- Rename the listener to not be called a "sink". If it were a "sink" it
would be eating bytes and conform with any of the Nix sink stuff
(maybe FileHandle should be a Sink itself! but that's a later CL's
problem). This is a parser listener.
- Move the RetrieveRegularNARSink thing into store-api.cc, which is its
only usage, and fix it to actually do what it is stated to do: crash
if its invariants are violated.
It's, of course, used to erm, unpack single-file NAR files, generated
via a horrible contraption of sources and sinks that looks like a
plumbing blueprint. Refactoring that is a future task.
- Add a description of the invariants of NARParseVisitor in preparation
of refactoring it.
Change-Id: Ifca1d74d2947204a1f66349772e54dad0743e944
while gcc 12 and older miscompile our generators, gcc 13 and older
outright crash on kj coroutines. (newer gcc versions may fix this)
Change-Id: I19f12c8c147239680eb0fa5a84ef5c7de38c9263
using a proper event loop basis we no longer have to worry about most of
the intricacies of poll(), or platform-dependent replacements for it. we
may even be able to use the event loop and its promise system for all of
our scheduling in the future. we don't do any real async processing yet,
this is just preparation to separate the first such change from the huge
api design difference with the async framework we chose (kj from capnp):
kj::Promise, unlike std::future, doesn't return exceptions unmangled. it
instead wraps any non-kj exception into a kj exception, erasing all type
information and preserving mostly the what() string in the process. this
makes sense in the capnp rpc use case where unrestricted exception types
can't be transferred, and since it moves error handling styles closer to
a world we'd actually like there's no harm in doing it only here for now
Change-Id: I20f888de74d525fb2db36ca30ebba4bcfe9cc838
we're using boost::outcome rather than leaf or stl types because stl
types are not available everywhere and leaf does not provide its own
storage for error values, relying on thread-locals and the stack. if
we want to use promises we won't have a stack and would have to wrap
everything into leaf-specific allocating wrappers, so outcome it is.
Change-Id: I35111a1f9ed517e7f12a839e2162b1ba6a993f8f
When the multi-line log format is enabled, the progress bar usually occupies
multiple lines on the screen. When stopping the progress bar, only the last
line was wiped, leaving all others visible on the screen. Erase all lines
belonging to the progress bar to prevent these leftovers.
Asking the user for input is theoretically affected by a similar issue, but
this is not observed in practice since the only place where the user is asked
(whether configuration options coming from flakes should be accepted) does not
actually have multiple lines on the progress bar. However, there is no real
reason to not fix this either, so let's do it anyway.
Change-Id: Iaa5a701874fca32e6f06d85912835d86b8fa7a16
The AcceptFlakeConfig type used was missing its JSON serialisation definition,
so it was incorrectly serialised as an integer, ending up that way for example
in the nix.conf manual page. Declare a proper serialisation.
Change-Id: If8ec210f9d4dd42fe480c4e97d0a4920eb66a01e
The JSON serialisation should be declared in the header so that all translation
units can see it when needed, even though it seems that it has not been used
anywhere else so far. Unfortunately, this means we cannot use the
NLOHMANN_JSON_SERIALIZE_ENUM convenience macro, since it uses a slightly
different signature, but the code is not too bad either.
Change-Id: I6e2851b250e0b53114d2fecb8011ff1ea9379d0f
This is the repl overlay from my dotfiles, which I think provides a
reasonable and ergonomic set of variables. We can iterate on this over
time, or (perhaps?) provide a sentinel value like `repl-overlays =
<DEFAULT>` to include a "suggested default" overlay like this one.
Change-Id: I8eba3934c50fbac8367111103e66c7375b8d134e
it just makes sense to have it too, rather than just the pass/fail
information we keep so far. once we turn goals into something more
promise-shaped it'll also help detangle the current data flow mess
Change-Id: I915cf04d177cad849ea7a5833215d795326f1946
it doesn't have a purpose except cache priming, which is largely
irrelevant by default (since another code path already runs this
exact query). our store implementations do not benefit that much
from this either, and the more bursty load may indeed harm them.
Change-Id: I1cc12f8c21cede42524317736d5987f1e43fc9c9
updating statistics *immediately* when any counter changes declutters
things somewhat and makes useful status reports less dependent on the
current worker main loop. using callbacks will make it easier to move
the worker loop into kj entirely, using only promises for scheduling.
Change-Id: I695dfa83111b1ec09b1a54cff268f3c1d7743ed6
there's no reason to go through the event loop in these cases. returning
ContinueImmediately here is just a very convoluted way of jumping to the
state we've just set after unwinding one frame of the stack, which never
matters in the cases changed here because there are no live RAII guards.
Change-Id: I7c00948c22e3caf35e934c1a14ffd2d40efc5547
this is not ideal, but it's better than having this stuck in the worker
loop itself. setting ex on all failing goals is not problematic because
only toplevel goals can ever be observable, all the others are ignored.
notably only derivation goals ever set `ex`, substitution goals do not.
Change-Id: I02e2164487b2955df053fef3c8e774d557aa638a
this doesn't serve a great purpose yet except to confine construction of
goals to the stack frame of Worker::run() and its child frames. we don't
need this yet (and the goal constructors remain fully visible), but in a
future change that fully removes the current worker loop we'll need some
way of knowing which goals are top-level goals without passing the goals
themselves around. once that's possible we can remove visible goals as a
concept and rely on build result futures and a scheduler built upon them
Change-Id: Ia73cdeffcfb9ba1ce9d69b702dc0bc637a4c4ce6
whether goal errors are reported via the `ex` member or just printed to
the log depends on whether the goal is a toplevel goal or a dependency.
if goals are aware of this themselves we can move error printing out of
the worker loop, and since a running worker can only be used by running
goals it's totally sufficient to keep a `Worker::running` flag for this
Change-Id: I6b5cbe6eccee1afa5fde80653c4b968554ddd16f
jade
alois31
Rebecca Turner
Maximilian Bosch
eldritch horrors