sys_util: make IntoIovec return an actual vector

Allow IntoIovec to produce an iovec with more than one entry.

BUG=None
TEST=./build_test.py

Change-Id: I21e8512f3edb06d9c0be4a1707432dde9fda6e9e
Signed-off-by: Daniel Verkamp <dverkamp@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosvm/+/1815316
Tested-by: kokoro <noreply+kokoro@google.com>
Reviewed-by: Zach Reizner <zachr@chromium.org>
This commit is contained in:
Daniel Verkamp 2019-09-19 10:26:05 -07:00 committed by Commit Bot
parent 5d0415bc79
commit 21556bf5d8

View file

@ -107,15 +107,12 @@ fn raw_sendmsg<D: IntoIovec>(fd: RawFd, out_data: D, out_fds: &[RawFd]) -> Resul
let cmsg_capacity = CMSG_SPACE!(size_of::<RawFd>() * out_fds.len()); let cmsg_capacity = CMSG_SPACE!(size_of::<RawFd>() * out_fds.len());
let mut cmsg_buffer = CmsgBuffer::with_capacity(cmsg_capacity); let mut cmsg_buffer = CmsgBuffer::with_capacity(cmsg_capacity);
let mut iovec = iovec { let mut iovec = out_data.into_iovec();
iov_base: out_data.as_ptr() as *mut c_void,
iov_len: out_data.size(),
};
let mut msg = msghdr { let mut msg = msghdr {
msg_name: null_mut(), msg_name: null_mut(),
msg_namelen: 0, msg_namelen: 0,
msg_iov: &mut iovec as *mut iovec, msg_iov: iovec.as_mut_ptr(),
msg_iovlen: 1, msg_iovlen: 1,
msg_control: null_mut(), msg_control: null_mut(),
msg_controllen: 0, msg_controllen: 0,
@ -307,36 +304,29 @@ impl ScmSocket for UnixSeqpacket {
/// This trait is unsafe because interfaces that use this trait depend on the base pointer and size /// This trait is unsafe because interfaces that use this trait depend on the base pointer and size
/// being accurate. /// being accurate.
pub unsafe trait IntoIovec { pub unsafe trait IntoIovec {
/// Gets the base pointer of this `iovec`. /// Gets a vector of structures describing each contiguous region of a memory buffer.
fn as_ptr(&self) -> *const c_void; fn into_iovec(&self) -> Vec<libc::iovec>;
/// Gets the size in bytes of this `iovec`.
fn size(&self) -> usize;
} }
// Safe because this slice can not have another mutable reference and it's pointer and size are // Safe because this slice can not have another mutable reference and it's pointer and size are
// guaranteed to be valid. // guaranteed to be valid.
unsafe impl<'a> IntoIovec for &'a [u8] { unsafe impl<'a> IntoIovec for &'a [u8] {
// Clippy false positive: https://github.com/rust-lang/rust-clippy/issues/3480 fn into_iovec(&self) -> Vec<libc::iovec> {
#[allow(clippy::useless_asref)] vec![libc::iovec {
fn as_ptr(&self) -> *const c_void { iov_base: self.as_ref().as_ptr() as *const c_void as *mut c_void,
self.as_ref().as_ptr() as *const c_void iov_len: self.len(),
} }]
fn size(&self) -> usize {
self.len()
} }
} }
// Safe because volatile slices are only ever accessed with other volatile interfaces and the // Safe because volatile slices are only ever accessed with other volatile interfaces and the
// pointer and size are guaranteed to be accurate. // pointer and size are guaranteed to be accurate.
unsafe impl<'a> IntoIovec for VolatileSlice<'a> { unsafe impl<'a> IntoIovec for VolatileSlice<'a> {
fn as_ptr(&self) -> *const c_void { fn into_iovec(&self) -> Vec<libc::iovec> {
self.as_ptr() as *const c_void vec![libc::iovec {
} iov_base: self.as_ptr() as *const c_void as *mut c_void,
iov_len: self.size() as usize,
fn size(&self) -> usize { }]
self.size() as usize
} }
} }