This was removed in https://github.com/NixOS/nix/pull/11152. However,
we need it for the multi-threaded evaluator, because otherwise Boehm
GC will crash while scanning the thread stack:
#0 GC_push_all_eager (bottom=<optimized out>, top=<optimized out>) at extra/../mark.c:1488
#1 0x00007ffff74691d5 in GC_push_all_stack_sections (lo=<optimized out>, hi=<optimized out>, traced_stack_sect=0x0) at extra/../mark_rts.c:704
#2 GC_push_all_stacks () at extra/../pthread_stop_world.c:876
#3 GC_default_push_other_roots () at extra/../os_dep.c:2893
#4 0x00007ffff746235c in GC_mark_some (cold_gc_frame=0x7ffee8ecaa50 "`\304G\367\377\177") at extra/../mark.c:374
#5 0x00007ffff7465a8d in GC_stopped_mark (stop_func=stop_func@entry=0x7ffff7453c80 <GC_never_stop_func>) at extra/../alloc.c:875
#6 0x00007ffff7466724 in GC_try_to_collect_inner (stop_func=0x7ffff7453c80 <GC_never_stop_func>) at extra/../alloc.c:624
#7 0x00007ffff7466a22 in GC_collect_or_expand (needed_blocks=needed_blocks@entry=1, ignore_off_page=ignore_off_page@entry=0, retry=retry@entry=0) at extra/../alloc.c:1688
#8 0x00007ffff746878f in GC_allocobj (gran=<optimized out>, kind=<optimized out>) at extra/../alloc.c:1798
#9 GC_generic_malloc_inner (lb=<optimized out>, k=k@entry=1) at extra/../malloc.c:193
#10 0x00007ffff746cd40 in GC_generic_malloc_many (lb=<optimized out>, k=<optimized out>, result=<optimized out>) at extra/../mallocx.c:477
#11 0x00007ffff746cf35 in GC_malloc_kind (bytes=120, kind=1) at extra/../thread_local_alloc.c:187
#12 0x00007ffff796ede5 in nix::allocBytes (n=<optimized out>, n=<optimized out>) at ../src/libexpr/include/nix/expr/eval-inline.hh:19
This is because it will use the stack pointer of the coroutine, so it
will scan a region of memory that doesn't exist, e.g.
Stack for thread 0x7ffea4ff96c0 is [0x7ffe80197af0w,0x7ffea4ffa000)
(where 0x7ffe80197af0w is the sp of the coroutine and 0x7ffea4ffa000
is the base of the thread stack).
We don't scan coroutine stacks, because currently they don't have GC
roots (there is no evaluation happening in coroutines). So there is
currently no need to restore the other parts of the original patch,
such as BoehmGCStackAllocator.
I had not wanted to cause unncessary churn before, but now that we've
bitten the bullet with the Big Reformat, I feel it is the right time.
Future readers will appreciate that the declarations and definitions
files are one-to-one as they should be, and `store-api.cc` is good to
shrink in any event.
I don't think there are outstanding PRs changing this code either. (I
had some for a while, but they are all merged.)
- No more private constructor that is kinda weird
- Two new static functions, `baseFromSize` and `baseFromSize`, that do
one thing, and one thing only (simple).
- Two `Hash::parse*` that previously used the private constructor now
can use these two functions directly.
- The remaining `Hash::parseAny*` methods, which are inherently more
complex, are written in terms of a `parseAnyHelper` static function
which is also complex, but keeps the complexity in one spot.
This patch allows users to specify the connection port
in the store URLS like so:
```
nix store info --store "ssh-ng://localhost:22" --json
```
Previously this failed with: `error: failed to start SSH connection to 'localhost:22'`,
because the code did not distinguish the port from the hostname. This
patch remedies that problem by introducing a ParsedURL::Authority type
for working with parsed authority components of URIs.
Now that the URL parsing code is less ad-hoc we can
add more long-awaited fixes for specifying SSH connection
ports in store URIs.
Builds upon the work from bd1d2d1041.
Co-authored-by: Sergei Zimmerman <sergei@zimmerman.foo>
Co-authored-by: John Ericson <John.Ericson@Obsidian.Systems>
Prior to this patch, mode 0444 is not updated to 0555 for directories.
That means for instance 0554 is canonicalized, but not 0444.
We don't believe this has any implications for backwards compatibility,
because directories do not have permissions in NAR format and so are
always 0555 after deserialization, and store paths with wrong
permissions can’t be copied to another host.
Co-authored-by: Robert Hensing <robert@roberthensing.nl>
Make it separate from Hash, since other things can be base-encoded too.
This isn't really needed for Nix, but it makes the code easier to read
e.g. for someone reimplementing this stuff in a different language. (Of
course, Base16/Base64 should be gotten off-the-shelf, but now the hash
code, which is more bespoke, is less cluttered with the parts that would
be from some library.)
Many reimplementations of "Nix32" and our hash type already exist, so
this cleanup is coming years too late, but I say better late than never
/ it is always good to nudge the code in the direction of being a
"living spec".
Co-authored-by: Sergei Zimmerman <sergei@zimmerman.foo>
Having a State class in the nix namespace is asking
for ODR trouble. This class is already private to the
translation unit, let's move it into an anonymous namespace.
There have been prior concerns about reogranizing the repo, but
this seems like a trivial simplification which will not interfere
with either our packaging or the modular builds in nixpkgs.
This adds the necessary infrastructure to collect
code coverage in CI, which could be useful to look
at munually or track consistently via something like
codecov.
Co-authored-by: Jade Lovelace <lix@jade.fyi>
This keeps things fast by making the function inline, but also prevents
people from having to know about the `0xFF` implementation detail
directly, instead making one go through a `std::optional` (which could be
fused away with a sufficiently smart compiler).
Additionally, the base "nix32" implementation is moved to its own header
file pair, as it is logically distinct and prior to the `Hash` data
type. It would probably be nice to do this with all the hash format
implementations.
Some binary caches (incorrectly) use this header to indicate lack of
compression, inspired by the valid "identity" token in the
"Accept-Encoding" header.
This benchmark should provide a relatively realistic
scenario for reference scanning.
As shown by the following results, reference scanning code
is already plenty fast and is definitely not a bottleneck:
```
BM_RefScanSinkRandom/10000 1672 ns 1682 ns 413354 bytes_per_second=5.53691Gi/s
BM_RefScanSinkRandom/100000 11217 ns 11124 ns 64341 bytes_per_second=8.37231Gi/s
BM_RefScanSinkRandom/1000000 205745 ns 204421 ns 3360 bytes_per_second=4.55591Gi/s
BM_RefScanSinkRandom/5000000 1208407 ns 1201046 ns 597 bytes_per_second=3.87713Gi/s
BM_RefScanSinkRandom/10000000 2534397 ns 2523344 ns 273 bytes_per_second=3.69083Gi/s
```
(Measurements on Ryzen 5900X via `nix build --file ci/gha/tests componentTests.nix-store-tests-run -L`)
The changes include:
* Defining nix32Chars as a constexpr char[].
* Adding a constexpr std::array<unsigned char, 256> (reverseNix32Map) to map characters to their base-32 digit values at compile time.
* Replacing the slow character search loop with a direct lookup using reverseNix32Map.
* Removing std::once_flag/isBase32 logic in references.cc in favor of reverseNix32Map
Signed-off-by: Alexander V. Nikolaev <avn@avnik.info>
