Fix a bug in linkat
#690
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Fix a bug in linkat
#690
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This commit fixes a longstanding issue in wasi-libc where the `linkat` function, when both parameters are `AT_FDCWD` or absolute paths, would relativize the two input paths in such a way that the previous stomped over the first, meaning that the wrong actual syscall was issued. This fixes the problem in the same manner as other two-path-taking functions which is to use `find_relpath` for one path and `find_relpath_alt` for the other path.
This was referenced Dec 10, 2025
yamt
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Dec 12, 2025
| char dst[] = "/dir/b"; | ||
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| TEST(mkdir("dir", 0700) == 0); | ||
| TEST((fd = open(src, flags | O_WRONLY | O_CREAT | O_EXCL, 0600)) > 2); |
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I'm hoping to work on clang-format after #685 is merged but for now it's a bit messy all the style in the repo, this is I believe not the first test with this for example.
abrown
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Dec 12, 2025
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LGTM! And thanks for the extra tests.
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…joboet std: Don't use `linkat` on the `wasm32-wasi*` targets This commit is a follow-up to rust-lang#147572 and the issue reported at the end of that PR where the `std::fs::hard_link` function is broken after that PR landed. The true culprit and bug here is fixed in WebAssembly/wasi-libc#690 but until that's released in a wasi-sdk version it should be reasonable, on WASI, to skip the `linkat` function.
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…joboet std: Don't use `linkat` on the `wasm32-wasi*` targets This commit is a follow-up to rust-lang#147572 and the issue reported at the end of that PR where the `std::fs::hard_link` function is broken after that PR landed. The true culprit and bug here is fixed in WebAssembly/wasi-libc#690 but until that's released in a wasi-sdk version it should be reasonable, on WASI, to skip the `linkat` function.
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…joboet std: Don't use `linkat` on the `wasm32-wasi*` targets This commit is a follow-up to rust-lang#147572 and the issue reported at the end of that PR where the `std::fs::hard_link` function is broken after that PR landed. The true culprit and bug here is fixed in WebAssembly/wasi-libc#690 but until that's released in a wasi-sdk version it should be reasonable, on WASI, to skip the `linkat` function.
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Rollup merge of #149864 - alexcrichton:wasi-avoid-linkat, r=joboet std: Don't use `linkat` on the `wasm32-wasi*` targets This commit is a follow-up to #147572 and the issue reported at the end of that PR where the `std::fs::hard_link` function is broken after that PR landed. The true culprit and bug here is fixed in WebAssembly/wasi-libc#690 but until that's released in a wasi-sdk version it should be reasonable, on WASI, to skip the `linkat` function.
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Dec 18, 2025
std: Don't use `linkat` on the `wasm32-wasi*` targets This commit is a follow-up to rust-lang/rust#147572 and the issue reported at the end of that PR where the `std::fs::hard_link` function is broken after that PR landed. The true culprit and bug here is fixed in WebAssembly/wasi-libc#690 but until that's released in a wasi-sdk version it should be reasonable, on WASI, to skip the `linkat` function.
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This commit fixes a longstanding issue in wasi-libc where the
linkatfunction, when both parameters areAT_FDCWDor absolute paths, would relativize the two input paths in such a way that the previous stomped over the first, meaning that the wrong actual syscall was issued. This fixes the problem in the same manner as other two-path-taking functions which is to usefind_relpathfor one path andfind_relpath_altfor the other path.