libutil: Get rid of double-quoting and .string() calls in file-system.cc#15330
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Significantly reduces the amount of churny .string() conversions when we don't need them and gets rid of annoying double-quoting issues once again.
xokdvium
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Feb 24, 2026
| mode, | ||
| { | ||
| .truncateExisting = true, | ||
| .followSymlinksOnTruncate = true, /* FIXME: Do we want this? */ |
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I think we ought to tighten this down for hardening reasons tbh.
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Caller should always open the file descriptor, and this function should go away.
xokdvium
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Feb 24, 2026
| auto st = lstat(path); | ||
| if (S_ISREG(st.st_mode)) { | ||
| AutoCloseFD fd = toDescriptor(open(path.string().c_str(), O_RDONLY, 0)); | ||
| AutoCloseFD fd = openFileReadonly(path); /* TODO: O_NOFOLLOW? */ |
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This lacked O_NOFOLLOW so technically there was a TOCTOU issue, but since it's just for fsync it's not too bad.
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Yeah this whole file is TOCTOU city :)
Ericson2314
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Feb 24, 2026
amaanq
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Feb 25, 2026
Six translation units failed to compile or link when targeting `x86_64-w64-mingw32`. `ExecutablePath::render` used `PathView` (narrow `string_view`) where `OsStringView` is needed since `p.native()` returns `std::wstring` on Windows. `createTempFile` used `_wmkstemp`, which mingw does not provide; replaced with `_wmktemp` plus `_wopen`. `PosixSourceAccessor::readLink` needed `.string()` on the `std::filesystem::path` returned by `nix::readLink` after NixOS#15330 changed the return type. `unix-domain-socket.cc` passed a `wchar_t*` to `unlink` and a bare `Descriptor` to `nix::bind`; use `_wunlink` and `toSocket()`. `windows/file-path.cc` had `static` linkage on `maybePath` conflicting with the `extern` declaration in the header.
amaanq
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Several translation units failed to compile for `x86_64-w64-mingw32`, mostly exposed by the file-system refactor in NixOS#15330.
amaanq
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Several translation units failed to compile for `x86_64-w64-mingw32`, mostly exposed by the file-system refactor in NixOS#15330.
amaanq
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Several translation units failed to compile for `x86_64-w64-mingw32`, mostly exposed by the file-system refactor in NixOS#15330.
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Apr 1, 2026
…o-string libutil: Get rid of double-quoting and .string() calls in file-system.cc
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Motivation
Significantly reduces the amount of churny .string() conversions when
we don't need them and gets rid of annoying double-quoting issues once again.
Note that .fsync() is currently and was always broken on windows due to the required GENERIC_WRITE for FlushFileBuffers.
https://learn.microsoft.com/en-us/previous-versions/ms960615(v=msdn.10)
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