src/vendor/nix/src/sys/ioctl/platform/linux.rs

   1 pub const NRBITS: u32 = 8;
   2 pub const TYPEBITS: u32 = 8;
   3
   4 #[cfg(any(target_arch = "mips", target_arch = "powerpc"))]
   5 mod consts {
   6     pub const NONE: u8 = 1;
   7     pub const READ: u8 = 2;
   8     pub const WRITE: u8 = 4;
   9     pub const SIZEBITS: u8 = 13;
  10     pub const DIRBITS: u8 = 3;
  11 }
  12
  13 #[cfg(not(any(target_arch = "powerpc",
  14               target_arch = "mips",
  15               target_arch = "x86",
  16               target_arch = "arm",
  17               target_arch = "x86_64",
  18               target_arch = "aarch64")))]
  19 use this_arch_not_supported;
  20
  21 // "Generic" ioctl protocol
  22 #[cfg(any(target_arch = "x86",
  23           target_arch = "arm",
  24           target_arch = "x86_64",
  25           target_arch = "aarch64"))]
  26 mod consts {
  27     pub const NONE: u8 = 0;
  28     pub const READ: u8 = 2;
  29     pub const WRITE: u8 = 1;
  30     pub const SIZEBITS: u8 = 14;
  31     pub const DIRBITS: u8 = 2;
  32 }
  33
  34 pub use self::consts::*;
  35
  36 pub const NRSHIFT: u32 = 0;
  37 pub const TYPESHIFT: u32 = NRSHIFT + NRBITS as u32;
  38 pub const SIZESHIFT: u32 = TYPESHIFT + TYPEBITS as u32;
  39 pub const DIRSHIFT: u32 = SIZESHIFT + SIZEBITS as u32;
  40
  41 pub const NRMASK: u32 = (1 << NRBITS) - 1;
  42 pub const TYPEMASK: u32 = (1 << TYPEBITS) - 1;
  43 pub const SIZEMASK: u32 = (1 << SIZEBITS) - 1;
  44 pub const DIRMASK: u32 = (1 << DIRBITS) - 1;
  45
  46 /// Encode an ioctl command.
  47 #[macro_export]
  48 macro_rules! ioc {
  49     ($dir:expr, $ty:expr, $nr:expr, $sz:expr) => (
  50         (($dir as u32) << $crate::sys::ioctl::DIRSHIFT) |
  51         (($ty as u32) << $crate::sys::ioctl::TYPESHIFT) |
  52         (($nr as u32) << $crate::sys::ioctl::NRSHIFT) |
  53         (($sz as u32) << $crate::sys::ioctl::SIZESHIFT))
  54 }
  55
  56 /// Encode an ioctl command that has no associated data.
  57 #[macro_export]
  58 macro_rules! io {
  59     ($ty:expr, $nr:expr) => (ioc!($crate::sys::ioctl::NONE, $ty, $nr, 0))
  60 }
  61
  62 /// Encode an ioctl command that reads.
  63 #[macro_export]
  64 macro_rules! ior {
  65     ($ty:expr, $nr:expr, $sz:expr) => (ioc!($crate::sys::ioctl::READ, $ty, $nr, $sz))
  66 }
  67
  68 /// Encode an ioctl command that writes.
  69 #[macro_export]
  70 macro_rules! iow {
  71     ($ty:expr, $nr:expr, $sz:expr) => (ioc!($crate::sys::ioctl::WRITE, $ty, $nr, $sz))
  72 }
  73
  74 /// Encode an ioctl command that both reads and writes.
  75 #[macro_export]
  76 macro_rules! iorw {
  77     ($ty:expr, $nr:expr, $sz:expr) => (ioc!($crate::sys::ioctl::READ | $crate::sys::ioctl::WRITE, $ty, $nr, $sz))
  78 }
  79
  80 /// Extracts the "direction" (read/write/none) from an encoded ioctl command.
  81 #[inline(always)]
  82 pub fn ioc_dir(nr: u32) -> u8 {
  83     ((nr >> DIRSHIFT) & DIRMASK) as u8
  84 }
  85
  86 /// Extracts the type from an encoded ioctl command.
  87 #[inline(always)]
  88 pub fn ioc_type(nr: u32) -> u32 {
  89     (nr >> TYPESHIFT) & TYPEMASK
  90 }
  91
  92 /// Extracts the ioctl number from an encoded ioctl command.
  93 #[inline(always)]
  94 pub fn ioc_nr(nr: u32) -> u32 {
  95     (nr >> NRSHIFT) & NRMASK
  96 }
  97
  98 /// Extracts the size from an encoded ioctl command.
  99 #[inline(always)]
 100 pub fn ioc_size(nr: u32) -> u32 {
 101     ((nr >> SIZESHIFT) as u32) & SIZEMASK
 102 }
 103
 104 pub const IN: u32 = (WRITE as u32) << DIRSHIFT;
 105 pub const OUT: u32 = (READ as u32) << DIRSHIFT;
 106 pub const INOUT: u32 = ((READ|WRITE) as u32) << DIRSHIFT;
 107 pub const SIZE_MASK: u32 = SIZEMASK << SIZESHIFT;