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Reduce CString allocations in std as much as possible Currently, every operation involving paths in `fs` allocates memory to hold the path before sending it through the syscall. This PR instead uses a stack allocation (chosen size is somewhat arbitrary) when the path is short before falling back to heap allocations for long paths. Benchmarks show that the stack allocation is ~2x faster for short paths: ``` test sys::unix::fd::tests::bench_heap_path_alloc ... bench: 34 ns/iter (+/- 2) test sys::unix::fd::tests::bench_stack_path_alloc ... bench: 15 ns/iter (+/- 1) ``` For long paths, I couldn't find any measurable difference. --- I'd be surprised if I was the first to think of this, so I didn't fully flush out the PR. If this change is desirable, I'll make use of `run_with_cstr` across all platforms in every fs method (currently just unix open for testing). I also added an `impl From<FromBytesWithNulError>` which is presumably a no-no (or at least needs to be done in another PR). --- Also see https://github.com/nix-rust/nix/pull/1655 with a bunch of discussion where I'm doing something similar.
This directory contains the source code of the rust project, including:
- The test suite
- The bootstrapping build system
- Various submodules for tools, like cargo, etc.
For more information on how various parts of the compiler work, see the rustc dev guide.