diff --git a/.gitignore b/.gitignore index 274208fd..b721fd95 100644 --- a/.gitignore +++ b/.gitignore @@ -1,3 +1,4 @@ /target Cargo.lock /gen/linux +/.vscode \ No newline at end of file diff --git a/src/lib.rs b/src/lib.rs index 199cddef..3204531d 100644 --- a/src/lib.rs +++ b/src/lib.rs @@ -78,6 +78,59 @@ impl PartialEq for general::__kernel_timespec { #[cfg(feature = "general")] impl Eq for general::__kernel_timespec {} +#[cfg(feature = "general")] +pub mod cmsg_macros { + use crate::ctypes::{c_long, c_uint, c_uchar}; + use crate::general::{cmsghdr, msghdr}; + use core::mem::size_of; + use core::ptr; + + pub unsafe fn CMSG_ALIGN(len: c_uint) -> c_uint { + let c_long_size = size_of::() as c_uint; + (len + c_long_size - 1) & !(c_long_size - 1) + } + + pub unsafe fn CMSG_DATA(cmsg: *const cmsghdr) -> *mut c_uchar { + (cmsg as *mut c_uchar).offset(size_of::() as isize) + } + + pub unsafe fn CMSG_SPACE(len: c_uint) -> c_uint { + size_of::() as c_uint + CMSG_ALIGN(len) + } + + pub unsafe fn CMSG_LEN(len: c_uint) -> c_uint { + size_of::() as c_uint + len + } + + pub unsafe fn CMSG_FIRSTHDR(mhdr: *const msghdr) -> *mut cmsghdr { + if (*mhdr).msg_controllen < size_of::() as _ { + return ptr::null_mut(); + } + + (*mhdr).msg_control as *mut cmsghdr + } + + pub unsafe fn CMSG_NXTHDR(mhdr: *const msghdr, cmsg: *const cmsghdr) -> *mut cmsghdr { + // We convert from raw pointers to isize here, which may not be sound in a future version of Rust. + // Once the provenance rules are set in stone, it will be a good idea to give this function a once-over. + + let cmsg_len = (*cmsg).cmsg_len; + let next_cmsg = (cmsg as *mut u8).offset(CMSG_ALIGN(cmsg_len as _) as isize) as *mut cmsghdr; + let max = ((*mhdr).msg_control as usize) + ((*mhdr).msg_controllen as usize); + + if cmsg_len < size_of::() as _ { + return ptr::null_mut(); + } + + if next_cmsg.offset(1) as usize > max || next_cmsg as usize + CMSG_ALIGN(cmsg_len as _) as usize > max + { + return ptr::null_mut(); + } + + next_cmsg + } +} + // The rest of this file is auto-generated! #[cfg(feature = "errno")] #[cfg(target_arch = "arm")]