Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Fix p{read,write}v{,v2}'s encoding of the offset argument on Linux. (#…
…896) (#898) Unlike with `p{read,write}`, Linux's `p{read,write}v` syscall's offset argument is not passed in an endian-specific order. And, the expectation is for syscall wrappers to always pass both the high and low halves of the offset as separate arguments, even though on 64-bit architectures the low half is passed throgh as a 64-bit value containing the full offset and the kernel doesn't mask it. And `p{read,write}v2` follow the behavior of `p{read,write}`.
- Loading branch information
1 parent
6534992
commit 1c6013a
Showing
5 changed files
with
292 additions
and
154 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,80 @@ | ||
| /// Test seek positions related to file "holes". | ||
| #[cfg(any(apple, freebsdlike, linux_kernel, solarish))] | ||
| #[test] | ||
| fn test_seek_holes() { | ||
| use rustix::fs::{fstat, openat, seek, Mode, OFlags, SeekFrom, CWD}; | ||
| use std::io::Write; | ||
|
|
||
| let tmp = tempfile::tempdir().unwrap(); | ||
| let dir = openat(CWD, tmp.path(), OFlags::RDONLY, Mode::empty()).unwrap(); | ||
| let foo = openat( | ||
| &dir, | ||
| "foo", | ||
| OFlags::RDWR | OFlags::CREATE | OFlags::TRUNC, | ||
| Mode::RUSR | Mode::WUSR, | ||
| ) | ||
| .unwrap(); | ||
| let mut foo = std::fs::File::from(foo); | ||
|
|
||
| let stat = fstat(&foo).unwrap(); | ||
| let hole_size = stat.st_blksize as u64; | ||
|
|
||
| #[cfg(any(solarish, freebsdlike, netbsdlike))] | ||
| let hole_size = unsafe { | ||
| use std::os::unix::io::AsRawFd; | ||
|
|
||
| let r = libc::fpathconf(foo.as_raw_fd(), libc::_PC_MIN_HOLE_SIZE); | ||
|
|
||
| if r < 0 { | ||
| // Holes not supported. | ||
| return; | ||
| } | ||
|
|
||
| // Holes are supported. | ||
| core::cmp::max(hole_size, r as u64) | ||
| }; | ||
|
|
||
| foo.write_all(b"prefix").unwrap(); | ||
| assert_eq!( | ||
| seek(&foo, SeekFrom::Start(hole_size * 2)), | ||
| Ok(hole_size * 2) | ||
| ); | ||
| foo.write_all(b"suffix").unwrap(); | ||
| assert_eq!(seek(&foo, SeekFrom::Start(0)), Ok(0)); | ||
| assert_eq!(seek(&foo, SeekFrom::Current(0)), Ok(0)); | ||
| assert_eq!(seek(&foo, SeekFrom::Hole(0)), Ok(hole_size)); | ||
| assert_eq!(seek(&foo, SeekFrom::Hole(hole_size as i64)), Ok(hole_size)); | ||
| assert_eq!( | ||
| seek(&foo, SeekFrom::Hole(hole_size as i64 * 2)), | ||
| Ok(hole_size * 2 + 6) | ||
| ); | ||
| assert_eq!(seek(&foo, SeekFrom::Data(0)), Ok(0)); | ||
| assert_eq!( | ||
| seek(&foo, SeekFrom::Data(hole_size as i64)), | ||
| Ok(hole_size * 2) | ||
| ); | ||
| assert_eq!( | ||
| seek(&foo, SeekFrom::Data(hole_size as i64 * 2)), | ||
| Ok(hole_size * 2) | ||
| ); | ||
| } | ||
|
|
||
| #[test] | ||
| fn test_seek_offsets() { | ||
| use rustix::fs::{openat, seek, Mode, OFlags, SeekFrom, CWD}; | ||
|
|
||
| let f = openat(CWD, "Cargo.toml", OFlags::RDONLY, Mode::empty()).unwrap(); | ||
|
|
||
| match seek(&f, SeekFrom::Start(0)) { | ||
| Ok(_) => {} | ||
| Err(e) => panic!("seek failed with an unexpected error: {:?}", e), | ||
| } | ||
| for invalid_offset in &[i32::MIN as u64, !1 as u64, i64::MIN as u64] { | ||
| let invalid_offset = *invalid_offset; | ||
| match seek(&f, SeekFrom::Start(invalid_offset)) { | ||
| Err(rustix::io::Errno::INVAL) => {} | ||
| Ok(_) => panic!("seek unexpectedly succeeded"), | ||
| Err(e) => panic!("seek failed with an unexpected error: {:?}", e), | ||
| } | ||
| } | ||
| } |
Oops, something went wrong.