bors 1b225414f3 Auto merge of #93668 - SUPERCILEX:path_alloc, r=joshtriplett ... 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.		2022-10-09 15:07:10 +00:00
..
condvar	make Condvar, Mutex, RwLock const constructors work with unsupported impl	2022-06-27 12:37:06 +02:00
memchr	Move std::memchr to sys_common	2021-05-14 03:54:46 +02:00
net	Use implicit capture syntax in format_args	2022-03-10 10:23:40 -05:00
once	std: use futex in Once	2022-10-07 12:12:36 +02:00
remutex	std: make ReentrantMutex movable and const; simplify Stdout initialization	2022-09-03 14:05:28 +02:00
thread_local_key	avoid some int2ptr casts in thread_local_key tests	2022-08-11 09:39:25 -04:00
thread_parker	std: use futex-based locks and thread parker on Hermit	2022-09-09 11:56:50 +02:00
wtf8	Remove is_known_utf8 checks from more tests where it's no longer set.	2022-06-23 13:10:47 -07:00
backtrace.rs	Use implicit capture syntax in format_args	2022-03-10 10:23:40 -05:00
condvar.rs	make Condvar, Mutex, RwLock const constructors work with unsupported impl	2022-06-27 12:37:06 +02:00
fs.rs	Hide Repr details from io::Error, and rework io::Error::new_const.	2022-02-04 18:47:29 -08:00
io.rs	Avoid double panics when using TempDir in tests	2022-01-25 10:36:10 +00:00
lazy_box.rs	Leak pthreax_mutex_t when it's dropped while locked.	2022-06-16 12:09:12 +02:00
memchr.rs	Move std::memchr to sys_common	2021-05-14 03:54:46 +02:00
mod.rs	std: use futex in Once	2022-10-07 12:12:36 +02:00
mutex.rs	make Condvar, Mutex, RwLock const constructors work with unsupported impl	2022-06-27 12:37:06 +02:00
net.rs	Reduce CString allocations in std as much as possible	2022-10-03 11:13:17 -07:00
process.rs	Remove CommandEnv::apply	2021-12-29 10:07:44 +01:00
remutex.rs	std: make ReentrantMutex movable and const; simplify Stdout initialization	2022-09-03 14:05:28 +02:00
rwlock.rs	Auto merge of #98457 - japaric:gh98378, r=m-ou-se	2022-09-25 04:12:30 +00:00
tests.rs	std: move "mod tests/benches" to separate files	2020-08-31 02:56:59 +00:00
thread.rs	Relax memory ordering used in min_stack	2022-05-01 15:55:54 -07:00
thread_info.rs	Merge two THREAD_INFO.with and following RefCell borrow	2021-09-16 15:24:53 +02:00
thread_local_dtor.rs	Remove "sys isn't exported yet" phrase	2022-05-30 12:07:43 +02:00
thread_local_key.rs	update and extend some comments, and cfg-out some unused code	2022-08-22 09:14:33 -04:00
wtf8.rs	Auto merge of #96869 - sunfishcode:main, r=joshtriplett	2022-08-24 01:17:52 +00:00