diff options
Diffstat (limited to 'src/sys')
| -rw-r--r-- | src/sys/ioctl/mod.rs | 28 |
1 files changed, 25 insertions, 3 deletions
diff --git a/src/sys/ioctl/mod.rs b/src/sys/ioctl/mod.rs index 43114a5c..058fc60a 100644 --- a/src/sys/ioctl/mod.rs +++ b/src/sys/ioctl/mod.rs @@ -80,7 +80,22 @@ //! The return value for `ioctl` functions generated by the `ioctl!` macro are `nix::Error`s. //! These are generated by assuming the return value of the ioctl is `-1` on error and everything //! else is a valid return value. If this is not the case, `Result::map` can be used to map some -//! of the range of "good" values (-2..-Inf, 0..Inf) into a smaller range in a helper function. +//! of the range of "good" values (-Inf..-2, 0..Inf) into a smaller range in a helper function. +//! +//! Writing `ioctl`s generally use pointers as their data source and these should use the +//! `write_ptr` variant. But in some cases an `int` is passed directly. For these `ioctl`s use the +//! `write_int` variant of the `ioctl!` macro. This variant does not take a type as the last argument: +//! +//! ``` +//! # #[macro_use] extern crate nix; +//! const HCI_IOC_MAGIC: u8 = b'k'; +//! const HCI_IOC_HCIDEVUP: u8 = 1; +//! ioctl!(write_int hci_dev_up with HCI_IOC_MAGIC, HCI_IOC_HCIDEVUP); +//! # fn main() {} +//! ``` +//! +//! Some `ioctl`s don't transfer any data, and those should use the `none` variant. This variant +//! doesn't take a type and so it is declared similar to the `write_int` variant shown above. //! //! The mode for a given `ioctl` should be clear from the documentation if it has good //! documentation. Otherwise it will be clear based on the macro used to generate the `ioctl` @@ -196,13 +211,20 @@ macro_rules! ioctl { convert_ioctl_res!($crate::libc::ioctl(fd, ior!($ioty, $nr, ::std::mem::size_of::<$ty>()) as $crate::sys::ioctl::ioctl_num_type, data)) } ); - (write $name:ident with $ioty:expr, $nr:expr; $ty:ty) => ( + (write_ptr $name:ident with $ioty:expr, $nr:expr; $ty:ty) => ( pub unsafe fn $name(fd: $crate::libc::c_int, - data: $ty) + data: *const $ty) -> $crate::Result<$crate::libc::c_int> { convert_ioctl_res!($crate::libc::ioctl(fd, iow!($ioty, $nr, ::std::mem::size_of::<$ty>()) as $crate::sys::ioctl::ioctl_num_type, data)) } ); + (write_int $name:ident with $ioty:expr, $nr:expr) => ( + pub unsafe fn $name(fd: $crate::libc::c_int, + data: $crate::libc::c_int) + -> $crate::Result<$crate::libc::c_int> { + convert_ioctl_res!($crate::libc::ioctl(fd, iow!($ioty, $nr, ::std::mem::size_of::<$crate::libc::c_int>()) as $crate::sys::ioctl::ioctl_num_type, data)) + } + ); (readwrite $name:ident with $ioty:expr, $nr:expr; $ty:ty) => ( pub unsafe fn $name(fd: $crate::libc::c_int, data: *mut $ty) |