Commit graph

15998 commits

Author SHA1 Message Date
jade 4fa6961aa2 Merge "gc: refactor the gc server thread out into a class without changing it" into main 2024-07-21 10:36:10 +00:00
Winter Cute 1917e6c765 Merge "Fix namespace warning being emitted if sandbox is disabled" into main 2024-07-20 22:14:33 +00:00
Qyriad 72ee25b402 libexpr: add a strongly typed version of gcAllocBytes()
This commit adds a new helper template function to gc-alloc.hh (which is
probably where you want to look at first, O great reviewer [custom file
ordering in review diffs when]), which uses a type argument to determine
the size to allocate, rather than making the caller use sizeof().

Change-Id: Ib5d138d91a28bdda304a80db24ea9fb08669ad22
2024-07-20 20:20:01 +00:00
Qyriad e67dac1d74 libexpr: rename confusing makeImmutableString -> gcCopyStringIfNeeded
The purpose of this function has little to do with immutability. Value's
strings are never mutated, and the point of this function is to
singleton empty strings.

Change-Id: Ifd41dd952409d54e4d3de9ab59064e6928b0e480
2024-07-20 20:20:01 +00:00
Qyriad a3361557e3 libexpr: refactor gc-agnostic helpers into one place
Change-Id: Icc4b367e4f670d47256f62a3a002cd248a5c2d3b
2024-07-20 20:20:01 +00:00
eldritch horrors 0109368c3f libutil: make basic loggers thread-safe
SimpleLogger is not fully thread-safe, and all loggers that wrap it are
also not safe accordingly. this does not affect much, but in rare cases
it can cause interleaving of messages on stderr when used with the json
or raw log formats. the fix applied here is a bit of a hack, but fixing
this properly requires rearchitecting the logger infrastructure. nested
loggers are not the most natural abstraction here, and it is biting us.

Change-Id: Ifbf34fe1e85c60e73b59faee50e7411c7b5e7c12
2024-07-20 12:33:49 +00:00
eldritch horrors d8c09b5836 libutil: remove warnOnce macro
it's only used once, and even that one use is highly questionable. more
instances of warnOnce should be much more principled than this has been

Change-Id: I5856570c99cb44462e700d753d0c706a5db03c4b
2024-07-20 12:33:49 +00:00
Winter Cute 3da41fdb82 Fix namespace warning being emitted if sandbox is disabled
If useChroot = false, and user namespaces aren't available for some
reason (e.g. within a Docker container), this fixes a pointless warning
being emitted, as we would never attempt to use them even if they were
available.

Change-Id: Ibcee91c088edd2cd19e70218d5a5802bff8f537b
2024-07-19 19:14:54 -04:00
jade 77ff799cc8 gc: refactor the gc server thread out into a class without changing it
This removes a *whole load* of variables from scope and enforces thread
boundaries with the type system.

There is not much change of significance in here, so the things to watch
out for while reviewing it are primarily that the destructor ordering
may have changed inadvertently, I think.

Change-Id: I3cd87e6d5a08dfcf368637407251db22a8906316
2024-07-19 20:55:55 +00:00
jade 22252825c4 Merge changes Id8b3d289,Ib75ab5b8,I3792eeb3 into main
* changes:
  Fixup a bunch of references to nixos.org manuals
  Add release notes for removing overflow from Nix language
  expr: fix a compiler warning about different signs in comparison
2024-07-19 18:52:46 +00:00
alois31 aba5f19680 Merge changes I829581a3,I0016970d,I5dac8e77,Ib7560fe5 into main
* changes:
  doc/release-notes: add for pretty printing improvements
  libexpr/print: do not show elided nested items when there are none
  libexpr/print: never show empty attrsets or derivations as «repeated»
  libexpr/print: pretty-print idempotently
2024-07-19 06:40:13 +00:00
jade 26e56780ca Fixup a bunch of references to nixos.org manuals
(plus one reference to CppNix github)

Change-Id: Id8b3d2897f3b54e286861805cfd421adc4d5de47
2024-07-18 19:27:33 +00:00
jade 10cc3b288d Add release notes for removing overflow from Nix language
Change-Id: Ib75ab5b8b4d879035d7ee7678f9cd0c491a39c0a
2024-07-18 19:27:33 +00:00
jade 50a63f8435 expr: fix a compiler warning about different signs in comparison
We know that variable is >=0, so we can just cast it to unsigned.

Change-Id: I3792eeb3ca43e6a507cc44c1a70584d42b2acd7b
2024-07-18 19:27:33 +00:00
jade 5ee1e6ea98 Merge changes Ib20e9aa0,I178a038b,I29c7de04 into main
* changes:
  docs: document the actual comparison rules instead of lies
  daemon: remove workaround for macOS kernel bug that seems fixed
  daemon: fix a crash bug "FATAL: exception not rethrown"
2024-07-18 17:40:32 +00:00
alois31 768d1f29a2
doc/release-notes: add for pretty printing improvements
Change-Id: I829581a3f5b8b742e6c866dcdbbc635f91afceb5
2024-07-18 19:08:20 +02:00
alois31 40c39aa5d2
libexpr/print: do not show elided nested items when there are none
When the configured maximum depth has been reached, attribute sets and lists
are printed with ellipsis to indicate the elision of nested items. Previously,
this happened even in case the structure being printed is empty, so that such
items do not in fact exist. This is confusing, so stop doing it.

Change-Id: I0016970dad3e42625e085dc896e6f476b21226c9
2024-07-18 18:41:34 +02:00
alois31 b5da823138
libexpr/print: never show empty attrsets or derivations as «repeated»
The repeated value detection logic exists so that the occurrence of large
common substructures does not fill up the screen or the computer's memory.
However, empty attribute sets and derivations (when their detection is enabled)
are always cheap to print, and in practice I have observed them to make up a
significant majority of the cases where I was annoyed by the repeated value
detection kicking in. Furthermore, `nix-instantiate --eval` already disables
this logic for empty attribute sets, and empty lists are already exempted
everywhere. For these reasons, always print empty attribute sets and
derivations as what they are.

Change-Id: I5dac8e7739f9d726b76fd0521ec46f38af94463f
2024-07-18 18:41:34 +02:00
alois31 81a0624d76
libexpr/print: pretty-print idempotently
When pretty-printing is enabled, previously an unforced thunk would trigger
indentation, even when it subsequently does not evaluate to a nested structure.
The resulting output looked inconsistent, and furthermore pretty-printing was
not idempotent (since pretty-printing the same value again, which is now fully
evaluated, will not trigger indentation).
When strict evaluation is enabled, force the item before inspecting its type,
so that it is properly known whether it contains a nested structure.
Furthermore, there is no need to cause indentation for unforced thunks, since
the very next operation will be printing them as `«thunk»`.

This is mostly a port of https://github.com/NixOS/nix/pull/11100 , but we only
force the item when it's going to be forced anyway due to strict
pretty-printing, and a new test was written since the REPL testing framework in
Lix is different.

Co-Authored-By: Robert Hensing <robert@roberthensing.nl>
Change-Id: Ib7560fe531d09e05ca6b2037a523fe21a26d9d58
2024-07-18 18:41:28 +02:00
alois31 7b1abf8107 Merge "doc/manual: clarify documentation related to the $$ parser bug" into main 2024-07-18 15:01:20 +00:00
alois31 72db9cd67b doc/release-notes: link the upcoming release notes again
The insertion marker comment broke the list into two parts, the first
containing only the link to the upcoming release notes and the second the
past releases. This confused the generator, leading to the first part being
discarded. Indent the marker comment so that it's syntactically part of the
preceding item, and in particular doesn't split the list any more.

Change-Id: I357c51bb03e4e0d79a76d30158615fd9eda95ea8
2024-07-17 22:12:41 +00:00
raito 67f62bcdb4 doc/release-notes: add date for major release
Change-Id: I93aab93c069bb3989c3f8d17e0862899e6f76865
Signed-off-by: Raito Bezarius <raito@lix.systems>
2024-07-17 22:12:41 +00:00
alois31 beb231784e doc/manual: clarify documentation related to the $$ parser bug
Due to a mistake in the grammar, a dollar character implicitly escapes a second
dollar character that immediately follows, so that it cannot start an
interpolation. Unfortunately, this behaviour has since come to be relied upon,
so it cannot be fixed. Furthermore, the documentation on regular strings did
not mention this behaviour at all, while in the case of indented strings it was
rather implicit.
Mention it explicitly in both cases, and describe how an interpolation can
follow a dollar character (namely, by escaping that). Since we have to touch
that section anyway, state that any character (other than n, r, and t; but
notably including `$` even if not succeeded by `{`) can be escaped using a
backslash in regular strings.

Change-Id: I7e5d68a9a4130eec98ce8218b485168f4b31a677
2024-07-17 22:01:48 +00:00
Max “Goldstein” Siling 68567206f2 Merge "tests/functional/repl.sh: actually fail test on wrong stdout" into main 2024-07-17 21:50:59 +00:00
Max “Goldstein” Siling 3a36c8bb90 tests/functional/repl.sh: actually fail test on wrong stdout
Previous test implementation assumed that grep supports newlines
in patterns. It doesn't, so tests spuriously passed, even though
some tests outputs were broken.

This patches output (and expected output) before grepping,
so there're no newlines in pattern.

Change-Id: Ie6561f9f2e18b83d976f162269d20136e2595141
2024-07-17 21:48:13 +00:00
eldritch horrors ef0de7c79f remove boost coroutine references
we no longer need these since sinkToSource and sourceToSink are gone.

Change-Id: Ibbf440e2cf71bf3e9f3b833af2d78a21fb1b3193
2024-07-16 01:50:16 +00:00
eldritch horrors dfedbc154f remove sourceToSink, sinkToSource, and boehm patch
Change-Id: I1379841299713175d0225b82a67f50660f9eb5e2
2024-07-16 01:50:16 +00:00
eldritch horrors d094dd0396 libstore: remove remaining sinkToSource uses
Change-Id: Id1ee0d2ad4a3774f4bbb960d76f0f76ac4f3eff9
2024-07-16 01:50:16 +00:00
eldritch horrors 6b4d46e9e0 libstore: remove WriteConn::sink fields
we no longer need these since we're no longer using sinks to serialize things.

Change-Id: Iffb1a3eab33c83f611c88fa4e8beaa8d5ffa079b
2024-07-16 00:57:42 +00:00
eldritch horrors a5d1f69841 libstore: generatorize protocol serializers
this is cursed. deeply and profoundly cursed. under NO CIRCUMSTANCES
must protocol serializer helpers be applied to temporaries! doing so
will inevitably cause dangling references and cause the entire thing
to crash. we need to do this even so to get rid of boost coroutines,
and likewise to encapsulate the serializers we suffer today at least
a little bit to allow a gradual migration to an actual IPC protocol.

(this isn't a problem that's unique to generators. c++ coroutines in
general cannot safely take references to arbitrary temporaries since
c++ does not have a lifetime system that can make this safe. -sigh-)

Change-Id: I2921ba451e04d86798752d140885d3c5cc08e146
2024-07-16 00:57:42 +00:00
eldritch horrors 5271424d14 libstore: remove a sinkToSouce from old daemon protocol
this doesn't have a test because this code path is only reached by
clients that predate 2.4, and we really should not be caring about
those any more right now. even the test suite doesn't, and the few
tests that might care are disabled because they will not even work

Change-Id: Id9eb190065138fedb2c7d90c328ff9eb9d97385b
2024-07-16 00:57:42 +00:00
eldritch horrors 4ec87742a1 libstore: rewrite the nar parser as a contents generator
this is not completely necessary at this point because the parser right
now already returns a generator to pass through all input data it read,
but the nar parser *was* very lax and would accept nars that weren't in
canonical form (defined as the form dumpPath would return). nar hashing
depends on these things, and as such rewriting the parser now allows us
to reject non-canonical nars that extract to the same store contents as
their canonical counterpart but have different nar hashes despite that.

Change-Id: Iccd319e3bd5912d8297014c84c495edc59019bb7
2024-07-16 00:57:42 +00:00
Qyriad c052716edd Merge changes I8d87c0e9,I25937702 into main
* changes:
  nix3-upgrade-nix: always use the /new/ nix-env to perform the installation
  libutil: implement a realPath() utility
2024-07-15 23:18:03 +00:00
eldritch horrors 3447dbfb2c libstore: rewrite narFromPath as generator
Change-Id: Ifa783c2c65c06ddd1d0212016d5bfd07666ea91c
2024-07-15 21:50:25 +00:00
Lunaphied 5e16b10cb1 Merge "use clangStdenv for the default devShell, so we get clangd by default" into main 2024-07-15 21:47:23 +00:00
Qyriad ae7eab49b9 nix3-upgrade-nix: always use the /new/ nix-env to perform the installation
Fixes #411.

Change-Id: I8d87c0e9295deea26ff33234e15ee33cc68ab303
2024-07-15 15:26:53 -06:00
Qyriad d9c51ec4e5 libutil: implement a realPath() utility
Just a wrapper around POSIX realpath().

Change-Id: I2593770285dbae573eace490efce5b272b00b001
2024-07-15 15:26:53 -06:00
nan-git 1eb5d22132 Merge "libexpr/eval.cc: remove unnecessary C string conversion" into main 2024-07-14 16:53:54 +00:00
nan-git 505640baec libexpr/eval.cc: remove unnecessary C string conversion
Change-Id: I5b7c21df84ff8ff64cf6a1e261fc3729a06bd4f6
2024-07-14 02:13:58 +00:00
Artemis Tosini 201e8b6994
nix-support/binary-tarball.nix: Pass through root paths
Passing through root paths allows external programs to see
which nix and cacert are in a binary tarball,
e.g. to recreate it from substituters

Change-Id: I27431134df53bbc6623484f8a0822004b51f7c87
2024-07-13 23:22:43 +00:00
jade 702f02c31f docs: document the actual comparison rules instead of lies
Although the comparison rules are ugly and we do not like various parts
of them, we must not hide them away for only catgirls to know about, so
the documentation should actually say how they work.

Change-Id: Ib20e9aa0e7b6486ade4f401035aafd85fbb08c91
2024-07-13 01:17:14 +02:00
jade 69e2ee5b25 daemon: remove workaround for macOS kernel bug that seems fixed
This was filed as https://github.com/nixos/nix/issues/7584, but as far
as I can tell, the previous solution of POLLHUP works just fine on macOS
14. I've also tested on an ancient machine with macOS 10.15.7, which
also has POLLHUP work correctly.

It's possible this might regress some older versions of macOS that have
a kernel bug, but I went looking through the history on the sources and
didn't find anything that looked terribly convincingly like a bug fix
between 2020 and today. If such a broken version exists, it seems pretty
reasonable to suggest simply updating the OS.

Change-Id: I178a038baa000f927ea2cbc4587d69d8ab786843
2024-07-13 01:17:14 +02:00
jade a8f443d960 docs: update to define integer overflow
Change-Id: Ie8a1b31035f2d27a220e5df2e9e178ec3b39ee68
2024-07-13 00:59:33 +02:00
jade b3fb8d9822 daemon: fix a crash bug "FATAL: exception not rethrown"
This is caused by pthread_cancel effectively throwing a
not-specifically-identifiable C++ exception into the targeted thread,
which, if it is not rethrown, terminates the process entirely.

This is rather "impolite" behaviour, we would say. But thread
cancellation is *always* busted, and we should simply not use it where
unnecessary. It's particularly unnecessary when what we *actually* need
it for is, err, interrupting a poll(2).

That can in turn be achieved by simply listening to more stuff in the
poll, namely, a pipe, which we send a character to when needing to
stop the thread.

While looking at this code, we also investigated whether any of the
poll() madness is required, or was even *ever* required. Curiously we
found in the XNU kernel source code that the thing about needing to
listen to POLLHUP is probably *correct*, but switching it to POLLRDNORM
should not have made any difference at all. We've left a FIXME to look
into that further because what's written here is super janky.

94d3b45284/bsd/kern/sys_generic.c (L1751-L1758)

This is the crash on some Hydra machines:

Thread 1 (Thread 0x7f56b77776c0 (LWP 955542) (Exiting)):
0  0x00007f56b8e9b7dc in __pthread_kill_implementation () from /nix/store/m71p7f0nymb19yn1dascklyya2i96jfw-glibc-2.39-52/lib/libc.so.6
1  0x00007f56b8e49516 in raise () from /nix/store/m71p7f0nymb19yn1dascklyya2i96jfw-glibc-2.39-52/lib/libc.so.6
2  0x00007f56b8e31935 in abort () from /nix/store/m71p7f0nymb19yn1dascklyya2i96jfw-glibc-2.39-52/lib/libc.so.6
3  0x00007f56b8e327f3 in __libc_message_impl.cold () from /nix/store/m71p7f0nymb19yn1dascklyya2i96jfw-glibc-2.39-52/lib/libc.so.6
4  0x00007f56b8e8e8e9 in __libc_fatal () from /nix/store/m71p7f0nymb19yn1dascklyya2i96jfw-glibc-2.39-52/lib/libc.so.6
5  0x00007f56b8ea23c4 in unwind_cleanup () from /nix/store/m71p7f0nymb19yn1dascklyya2i96jfw-glibc-2.39-52/lib/libc.so.6
6  0x00007f56b9d2a1b8 in nix::triggerInterrupt() [clone .cold] () from /nix/store/sahgw550p621m9dy1pd7whl9c5g1g0p7-lix-2.90.0-rc1/lib/liblixutil.so
7  0x00007f56b990ac9d in std:🧵:_State_impl<std:🧵:_Invoker<std::tuple<nix::MonitorFdHup::MonitorFdHup(int)::{lambda()#1}> > >::_M_run() () from /nix/store/sahgw550p621m9dy1pd7whl9c5g1g0p7-lix-2.90.0-rc1/lib/liblixstore.so
8  0x00007f56b90e86d3 in execute_native_thread_routine () from /nix/store/c6r62m84hywf4i6qq1h28f13zv38yqyp-gcc-13.3.0-lib/lib/libstdc++.so.6
9  0x00007f56b8e99a42 in start_thread () from /nix/store/m71p7f0nymb19yn1dascklyya2i96jfw-glibc-2.39-52/lib/libc.so.6
10 0x00007f56b8f1905c in clone3 () from /nix/store/m71p7f0nymb19yn1dascklyya2i96jfw-glibc-2.39-52/lib/libc.so.6

As for testing, we've started a daemon with this change and verified it
deals with HUPs correctly on x86_64-linux, but I don't think we can
easily test the destructor behaviour without whatever Hydra was
doing that broke.

Change-Id: I29c7de0425674494b6e43c075810126c3ff77363
2024-07-13 00:59:33 +02:00
jade 917c9bdee7 language: cleanly ban integer overflows
This also bans various sneaking of negative numbers from the language
into unsuspecting builtins as was exposed while auditing the
consequences of changing the Nix language integer type to a newtype.

It's unlikely that this change comprehensively ensures correctness when
passing integers out of the Nix language and we should probably add a
checked-narrowing function or something similar, but that's out of scope
for the immediate change.

During the development of this I found a few fun facts about the
language:
- You could overflow integers by converting from unsigned JSON values.
- You could overflow unsigned integers by converting negative numbers
  into them when going into Nix config, into fetchTree, and into flake
  inputs.

  The flake inputs and Nix config cannot actually be tested properly
  since they both ban thunks, however, we put in checks anyway because
  it's possible these could somehow be used to do such shenanigans some
  other way.

Note that Lix has banned Nix language integer overflows since the very
first public beta, but threw a SIGILL about them because we run with
-fsanitize=signed-overflow -fsanitize-undefined-trap-on-error in
production builds. Since the Nix language uses signed integers, overflow
was simply undefined behaviour, and since we defined that to trap, it
did.

Trapping on it was a bad UX, but we didn't even entirely notice
that we had done this at all until it was reported as a bug a couple of
months later (which is, to be fair, that flag working as intended), and
it's got enough production time that, aside from code that is IMHO buggy
(and which is, in any case, not in nixpkgs) such as
#445, we don't think
anyone doing anything reasonable actually depends on wrapping overflow.

Even for weird use cases such as doing funny bit crimes, it doesn't make
sense IMO to have wrapping behaviour, since two's complement arithmetic
overflow behaviour is so *aggressively* not what you want for *any* kind
of mathematics/algorithms. The Nix language exists for package
management, a domain where bit crimes are already only dubiously in
scope to begin with, and it makes a lot more sense for that domain for
the integers to never lose precision, either by throwing errors if they
would, or by being arbitrary-precision.

This change will be ported to CppNix as well, to maintain language
consistency.

Fixes: #423

Change-Id: I51f253840c4af2ea5422b8a420aa5fafbf8fae75
2024-07-13 00:59:33 +02:00
jade f9641b9efd libutil: add checked arithmetic tools
This is in preparation for adding checked arithmetic to the evaluator.

Change-Id: I6e115ce8f5411feda1706624977a4dcd5efd4d13
2024-07-13 00:56:37 +02:00
Lunaphied 0339b2fbd2 use clangStdenv for the default devShell, so we get clangd by default
The default-stdenv-devShell can always be used with `.#native-stdenvPackages`.

Change-Id: I9b3e72210ba5219b6b65c71a2818110769623904
2024-07-12 20:52:33 +00:00
jade dde51af97d Use std::strong_ordering for version comparison
The actual motive here is the avoidance of integer overflow if we were
to make these use checked NixInts and retain the subtraction.

However, the actual *intent* of this code is a three-way comparison,
which can be done with operator<=>, so we should just do *that* instead.

Change-Id: I7f9a7da1f3176424b528af6d1b4f1591e4ab26bf
2024-07-12 16:48:28 +02:00
eldritch horrors 4b109ec1a8 libstore: remove upcast_goal
upcast_goal was only ever needed to break circular includes, but the
same solution that gave us upcast_goal also lets us fully remove it:
just upcast goals without a wrapper function, but only in .cc files.

Change-Id: I9c71654b2535121459ba7dcfd6c5da5606904032
2024-07-11 21:31:52 +00:00
eldritch horrors a5d431a911 libstore: turn copyNAR into a generator
Change-Id: Id452f6a03faa1037ff13af0f63e32883966ff40d
2024-07-11 20:37:27 +00:00