This is required for other bindings like nix-flake-c to hook into
nix-expr-c appropriately.
The `_internal` part should be a sufficient deterrent normally,
and it may also be useful for bindings that migrate from the C++
interface.
For example, instead of doing
#include "nix/store-config.hh"
#include "nix/derived-path.hh"
Now do
#include "nix/store/config.hh"
#include "nix/store/derived-path.hh"
This was originally planned in the issue, and also recent requested by
Eelco.
Most of the change is purely mechanical. There is just one small
additional issue. See how, in the example above, we took this
opportunity to also turn `<comp>-config.hh` into `<comp>/config.hh`.
Well, there was already a `nix/util/config.{cc,hh}`. Even though there
is not a public configuration header for libutil (which also would be
called `nix/util/config.{cc,hh}`) that's still confusing, To avoid any
such confusion, we renamed that to `nix/util/configuration.{cc,hh}`.
Finally, note that the libflake headers already did this, so we didn't
need to do anything to them. We wouldn't want to mistakenly get
`nix/flake/flake/flake.hh`!
Progress on #7876
There are two big changes:
1. Public and private config is now separated. Configuration variables
that are only used internally do not go in a header which is
installed.
(Additionally, libutil has a unix-specific private config header,
which should only be used in unix-specific code. This keeps things a
bit more organized, in a purely private implementation-internal way.)
2. Secondly, there is no more `-include`. There are very few config
items that need to be publically exposed, so now it is feasible to
just make the headers that need them just including the (public)
configuration header.
And there are also a few more small cleanups on top of those:
- The configuration files have better names.
- The few CPP variables that remain exposed in the public headers are
now also renamed to always start with `NIX_`. This ensures they should
not conflict with variables defined elsewhere.
- We now always use `#if` and not `#ifdef`/`#ifndef` for our
configuration variables, which helps avoid bugs by requiring that
variables must be defined in all cases.
See comments on the script; this is supposed to avoid breaking muscle
memory without complicating the build system (which proved harder than I
thought too) or not doing the header hygiene change at all.
link-headers: use pathlib consistenly and fix type errors
The short answer for why we need to do this is so we can consistently do
`#include "nix/..."`. Without this change, there are ways to still make
that work, but they are hacky, and they have downsides such as making it
harder to make sure headers from the wrong Nix library (e..g.
`libnixexpr` headers in `libnixutil`) aren't being used.
The C API alraedy used `nix_api_*`, so its headers are *not* put in
subdirectories accordingly.
Progress on #7876
We resisted doing this for a while because it would be annoying to not
have the header source file pairs close by / easy to change file
path/name from one to the other. But I am ameliorating that with
symlinks in the next commit.
- Since it's now private, give it a rename. Note that I want to switch the
word order on the public ones too.
- Since it is only needed by two files, just include there rather than
the nasty blanket-forced thing.
On my system (Ubuntu 24.04 with nix installed using
https://zero-to-nix.com/), I noticed that my PATH
contained multiple times the following entries:
/home/thomas/.nix-profile/bin
/nix/var/nix/profiles/default/bin
Fix it by inserting a missing `export`, to make
sure `nix-daemon.sh` is really only executed once.
This makes it behave the same as nix-daemon. Opening the store in the
parent can cause a SIGBUS in libsqlite in the child:
#0 0x00007f141cf6f789 in __memset_avx2_unaligned_erms () from /nix/store/wn7v2vhyyyi6clcyn0s9ixvl7d4d87ic-glibc-2.40-36/lib/libc.so.6
#1 0x00007f141c322fe8 in walIndexAppend () from /nix/store/bbd59cqw259149r2ddk4w1q0lr2fch8c-sqlite-3.46.1/lib/libsqlite3.so.0
#2 0x00007f141c3711a2 in pagerWalFrames () from /nix/store/bbd59cqw259149r2ddk4w1q0lr2fch8c-sqlite-3.46.1/lib/libsqlite3.so.0
#3 0x00007f141c38317e in sqlite3PagerCommitPhaseOne.part.0 () from /nix/store/bbd59cqw259149r2ddk4w1q0lr2fch8c-sqlite-3.46.1/lib/libsqlite3.so.0
#4 0x00007f141c383555 in sqlite3BtreeCommitPhaseOne.part.0 () from /nix/store/bbd59cqw259149r2ddk4w1q0lr2fch8c-sqlite-3.46.1/lib/libsqlite3.so.0
#5 0x00007f141c384797 in sqlite3VdbeHalt () from /nix/store/bbd59cqw259149r2ddk4w1q0lr2fch8c-sqlite-3.46.1/lib/libsqlite3.so.0
#6 0x00007f141c3b8f60 in sqlite3VdbeExec () from /nix/store/bbd59cqw259149r2ddk4w1q0lr2fch8c-sqlite-3.46.1/lib/libsqlite3.so.0
#7 0x00007f141c3bbfef in sqlite3_step () from /nix/store/bbd59cqw259149r2ddk4w1q0lr2fch8c-sqlite-3.46.1/lib/libsqlite3.so.0
#8 0x00007f141c3bd0e5 in sqlite3_exec () from /nix/store/bbd59cqw259149r2ddk4w1q0lr2fch8c-sqlite-3.46.1/lib/libsqlite3.so.0
#9 0x00007f141da140e0 in nix::SQLiteTxn::commit() () from /nix/store/1m4r8s7s1v54zq9isncvjgia02bffxlz-determinate-nix-store-3.1.0/lib/libnixstore.so
#10 0x00007f141d9ce69c in nix::LocalStore::registerValidPaths(std::map<nix::StorePath, nix::ValidPathInfo, std::less<nix::StorePath>, std::allocator<std::pair<nix::StorePath const, nix::ValidPathInfo> > > const&)::{lambda()#1}::operator()() const () from /nix/store/1m4r8s7s1v54zq9isncvjgia02bffxlz-determinate-nix-store-3.1.0/lib/libnixstore.so
