Use c:: instead of libc:: and linux_raw_sys:: in more places. (#1307)

This helps unify some code between the two backends.

Author: sunfishcode

src/backend/libc/c.rs

@@ -479,15 +479,15 @@ bitflags! {
         /// created. `MCL_ONFAULT` must be used with either `MCL_CURRENT` or
         /// `MCL_FUTURE` or both.
         #[cfg(linux_kernel)]
-        const ONFAULT = bitcast!(libc::MCL_ONFAULT);
+        const ONFAULT = bitcast!(c::MCL_ONFAULT);
         /// Lock all pages which will become mapped into the address space of
         /// the process in the future. These could be, for instance, new pages
         /// required by a growing heap and stack as well as new memory-mapped
         /// files or shared memory regions.
-        const FUTURE = bitcast!(libc::MCL_FUTURE);
+        const FUTURE = bitcast!(c::MCL_FUTURE);
         /// Lock all pages which are currently mapped into the address space of
         /// the process.
-        const CURRENT = bitcast!(libc::MCL_CURRENT);
+        const CURRENT = bitcast!(c::MCL_CURRENT);
 
         /// <https://docs.rs/bitflags/*/bitflags/#externally-defined-flags>
         const _ = !0;

src/backend/libc/mm/types.rs

@@ -4,12 +4,13 @@
 
 #[cfg(feature = "alloc")]
 use crate::alloc::string::String;
+use crate::backend::c;
 use crate::backend::io::syscalls::ioctl;
 use crate::fd::AsFd;
 use crate::io;
 #[cfg(feature = "alloc")]
-use libc::SIOCGIFNAME;
-use libc::{__c_anonymous_ifr_ifru, c_char, ifreq, IFNAMSIZ, SIOCGIFINDEX};
+use c::SIOCGIFNAME;
+use c::{__c_anonymous_ifr_ifru, c_char, ifreq, IFNAMSIZ, SIOCGIFINDEX};
 
 pub(crate) fn name_to_index(fd: impl AsFd, if_name: &str) -> io::Result<u32> {
     let if_name_bytes = if_name.as_bytes();

src/backend/libc/net/netdevice.rs

@@ -66,7 +66,7 @@ pub(crate) fn ptsname(fd: BorrowedFd<'_>, mut buffer: Vec<u8>) -> io::Result<CSt
             if let Some(func) = ptsname_r.get() {
                 func(borrowed_fd(fd), buffer.as_mut_ptr().cast(), buffer.len())
             } else {
-                libc::ENOSYS
+                c::ENOSYS
             }
         };
 

src/backend/libc/pty/syscalls.rs

@@ -102,7 +102,7 @@ pub(crate) fn tcgetattr(fd: BorrowedFd<'_>) -> io::Result<Termios> {
         let mut result = MaybeUninit::<Termios>::uninit();
 
         // `result` is a `Termios` which starts with the same layout as
-        // `libc::termios`, so we can cast the pointer.
+        // `c::termios`, so we can cast the pointer.
         ret(c::tcgetattr(borrowed_fd(fd), result.as_mut_ptr().cast()))?;
 
         Ok(result.assume_init())

src/backend/libc/termios/syscalls.rs

@@ -665,7 +665,7 @@ pub(crate) fn setgroups_thread(groups: &[crate::ugid::Gid]) -> io::Result<()> {
 #[cfg(any(linux_kernel, target_os = "dragonfly"))]
 #[inline]
 pub(crate) fn sched_getcpu() -> usize {
-    let r = unsafe { libc::sched_getcpu() };
+    let r = unsafe { c::sched_getcpu() };
     debug_assert!(r >= 0);
     r as usize
 }

src/backend/libc/thread/syscalls.rs

@@ -50,24 +50,24 @@ impl From<Itimerspec> for LibcItimerspec {
 
 #[cfg(any(linux_kernel, target_os = "fuchsia"))]
 #[cfg(not(fix_y2038))]
-pub(crate) fn as_libc_itimerspec_ptr(itimerspec: &Itimerspec) -> *const libc::itimerspec {
+pub(crate) fn as_libc_itimerspec_ptr(itimerspec: &Itimerspec) -> *const c::itimerspec {
     #[cfg(test)]
     {
-        assert_eq_size!(Itimerspec, libc::itimerspec);
+        assert_eq_size!(Itimerspec, c::itimerspec);
     }
-    crate::utils::as_ptr(itimerspec).cast::<libc::itimerspec>()
+    crate::utils::as_ptr(itimerspec).cast::<c::itimerspec>()
 }
 
 #[cfg(any(linux_kernel, target_os = "fuchsia"))]
 #[cfg(not(fix_y2038))]
 pub(crate) fn as_libc_itimerspec_mut_ptr(
     itimerspec: &mut core::mem::MaybeUninit<Itimerspec>,
-) -> *mut libc::itimerspec {
+) -> *mut c::itimerspec {
     #[cfg(test)]
     {
-        assert_eq_size!(Itimerspec, libc::itimerspec);
+        assert_eq_size!(Itimerspec, c::itimerspec);
     }
-    itimerspec.as_mut_ptr().cast::<libc::itimerspec>()
+    itimerspec.as_mut_ptr().cast::<c::itimerspec>()
 }
 
 #[cfg(any(linux_kernel, target_os = "fuchsia"))]

src/backend/libc/time/types.rs

@@ -35,6 +35,13 @@ pub(crate) use linux_raw_sys::general::{
 #[cfg(test)]
 pub(crate) use linux_raw_sys::general::epoll_event;
 
+#[cfg(feature = "mm")]
+mod mm {
+    pub(crate) use linux_raw_sys::general::{MAP_HUGETLB, MAP_HUGE_SHIFT};
+}
+#[cfg(feature = "mm")]
+pub(crate) use mm::*;
+
 #[cfg(any(
     feature = "fs",
     all(

src/backend/linux_raw/c.rs

@@ -58,7 +58,7 @@ mod tests {
         assert!(CWD.as_raw_fd() != -1);
         #[cfg(linux_kernel)]
         #[cfg(feature = "io_uring")]
-        assert!(CWD.as_raw_fd() != linux_raw_sys::io_uring::IORING_REGISTER_FILES_SKIP);
+        assert!(CWD.as_raw_fd() != crate::io_uring::IORING_REGISTER_FILES_SKIP.as_raw_fd());
     }
 
     #[test]
@@ -68,6 +68,6 @@ mod tests {
         assert!(ABS.as_raw_fd() != c::AT_FDCWD);
         #[cfg(linux_kernel)]
         #[cfg(feature = "io_uring")]
-        assert!(ABS.as_raw_fd() != linux_raw_sys::io_uring::IORING_REGISTER_FILES_SKIP);
+        assert!(ABS.as_raw_fd() != crate::io_uring::IORING_REGISTER_FILES_SKIP.as_raw_fd());
     }
 }

src/fs/special.rs

@@ -34,9 +34,9 @@ impl MapFlags {
     /// ```
     #[cfg(linux_kernel)]
     pub const fn hugetlb_with_size_log2(huge_page_size_log2: u32) -> Option<Self> {
-        use linux_raw_sys::general::{MAP_HUGETLB, MAP_HUGE_SHIFT};
+        use crate::backend::c;
         if 16 <= huge_page_size_log2 && huge_page_size_log2 <= 63 {
-            let bits = MAP_HUGETLB | (huge_page_size_log2 << MAP_HUGE_SHIFT);
+            let bits = bitcast!(c::MAP_HUGETLB) | (huge_page_size_log2 << c::MAP_HUGE_SHIFT);
             Self::from_bits(bits)
         } else {
             None