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author | Homu <homu@barosl.com> | 2017-02-18 02:29:01 +0900 |
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committer | Homu <homu@barosl.com> | 2017-02-18 02:29:01 +0900 |
commit | e7629f3e91535464c5857820dfc18ac0795a6893 (patch) | |
tree | 68a68cf56e0b7097cbb786cca2637f0e9de4607d /src/sys/stat.rs | |
parent | 54e6197b32dc3583bde9df797b620b255a75885e (diff) | |
parent | dbd3b16508f103c9567d32ee784731e95ab40493 (diff) | |
download | nix-e7629f3e91535464c5857820dfc18ac0795a6893.zip |
Auto merge of #508 - aidanhs:aphs-major-minor-macros, r=posborne
Implement major/minor macros, correct mkdev
It appears that the previous `mkdev` was based on the kernel headers (https://github.com/torvalds/linux/blob/v4.7/include/linux/kdev_t.h#L6) which (I guess) is the internal kernel dev_t. Scrolling down the file you can see some bitshifting operations to do conversions.
The new implementation(s) are based on [musl](http://git.musl-libc.org/cgit/musl/tree/include/sys/sysmacros.h?id=dbbb3734d8c0176feabd6c46e2e85bbc3b8a60af) and [glibc](https://github.molgen.mpg.de/git-mirror/glibc/blob/20003c49884422da7ffbc459cdeee768a6fee07b/sysdeps/unix/sysv/linux/sys/sysmacros.h#L38), which are in agreement about how dev_t should be handled.
(as it happens I suspect we could omit the shift by 32 since I don't see that in the kernel headers, but doesn't hurt to take the conservative route and mimic the libcs)
Diffstat (limited to 'src/sys/stat.rs')
-rw-r--r-- | src/sys/stat.rs | 18 |
1 files changed, 15 insertions, 3 deletions
diff --git a/src/sys/stat.rs b/src/sys/stat.rs index 1beb349e..4bb4927a 100644 --- a/src/sys/stat.rs +++ b/src/sys/stat.rs @@ -63,11 +63,23 @@ pub fn mknod<P: ?Sized + NixPath>(path: &P, kind: SFlag, perm: Mode, dev: dev_t) } #[cfg(target_os = "linux")] -const MINORBITS: usize = 20; +pub fn major(dev: dev_t) -> u64 { + ((dev >> 32) & 0xfffff000) | + ((dev >> 8) & 0x00000fff) +} + +#[cfg(target_os = "linux")] +pub fn minor(dev: dev_t) -> u64 { + ((dev >> 12) & 0xffffff00) | + ((dev ) & 0x000000ff) +} #[cfg(target_os = "linux")] -pub fn mkdev(major: u64, minor: u64) -> dev_t { - (major << MINORBITS) | minor +pub fn makedev(major: u64, minor: u64) -> dev_t { + ((major & 0xfffff000) << 32) | + ((major & 0x00000fff) << 8) | + ((minor & 0xffffff00) << 12) | + ((minor & 0x000000ff) ) } pub fn umask(mode: Mode) -> Mode { |