This fixes segfaults with nix copy when there was an error processing
addMultipleToStore.
Running with ASAN/TSAN pointed at an use-after-free with threads from
the pool accessing the graph declared in processGraph after the function
was exiting and destructing the variables.
It turns out that if there is an error before pool.process() is called,
for example while we are still enqueuing tasks, then pool.process()
isn't called and threads are still left to run.
By creating the pool last we ensure that it is stopped first before
running other destructors even if an exception happens early.
[ lix porting note: nix does not name threads so the patch has been
adapted to not pass thread name ]
Link: https://git.lix.systems/lix-project/lix/issues/618
Link: https://gerrit.lix.systems/c/lix/+/2355
All OS and IO operations should be moved out, leaving only some misc
portable pure functions.
This is useful to avoid copious CPP when doing things like Windows and
Emscripten ports.
Newly exposed functions to break cycles:
- `restoreSignals`
- `updateWindowSize`
* Finish converting existing comments for internal API docs
99% of this was just reformatting existing comments. Only two exceptions:
- Expanded upon `BuildResult::status` compat note
- Split up file-level `symbol-table.hh` doc comments to get
per-definition docs
Also fixed a few whitespace goofs, turning leading tabs to spaces and
removing trailing spaces.
Picking up from #8133
* Fix two things from comments
* Use triple-backtick not indent for `dumpPath`
* Convert GNU-style `\`..'` quotes to markdown style in API docs
This will render correctly.
The worker threads could exit prematurely if they finished processing
all items while the main thread was still adding items. In particular,
this caused hanging nix-store --serve processes in the build farm.
Also, process items from the main thread.
In particular, process() won't return as long as there are active
items. This prevents work item lambdas from referring to stack frames
that no longer exist.
Unlike "nix-store --verify-path", this command verifies signatures in
addition to store path contents, is multi-threaded (especially useful
when verifying binary caches), and has a progress indicator.
Example use:
$ nix verify-paths --store https://cache.nixos.org -r $(type -p thunderbird)
...
[17/132 checked] checking ‘/nix/store/rawakphadqrqxr6zri2rmnxh03gqkrl3-autogen-5.18.6’
