Remove unused defs, add 'inhibit' sigcontrol flag.

src/call.rs

@@ -1,10 +1,10 @@
 use super::arch::*;
-use super::data::{Map, SigAction, Stat, StatVfs, TimeSpec};
+use super::data::{Map, Stat, StatVfs, TimeSpec};
 use super::error::Result;
 use super::flag::*;
 use super::number::*;
 
-use core::{mem, ptr};
+use core::mem;
 
 /// Close a file
 pub fn close(fd: usize) -> Result<usize> {

src/data.rs

@@ -2,8 +2,8 @@ use core::cell::SyncUnsafeCell;
 use core::ops::{Deref, DerefMut};
 use core::sync::atomic::AtomicU64;
 use core::{mem, slice};
-use crate::IntRegisters;
-use crate::flag::{EventFlags, MapFlags, PtraceFlags, SigActionFlags};
+
+use crate::flag::{EventFlags, MapFlags, PtraceFlags, SigcontrolFlags};
 
 #[derive(Copy, Clone, Debug, Default)]
 #[repr(C)]
@@ -145,41 +145,6 @@ impl DerefMut for Packet {
     }
 }
 
-#[derive(Copy, Clone, Debug, Default, PartialEq)]
-#[repr(C)]
-pub struct SigAction {
-    pub sa_handler: Option<extern "C" fn(usize)>,
-    pub sa_mask: u64,
-    pub sa_flags: SigActionFlags,
-}
-impl Deref for SigAction {
-    type Target = [u8];
-    fn deref(&self) -> &[u8] {
-        unsafe {
-            slice::from_raw_parts(self as *const SigAction as *const u8,
-                                  mem::size_of::<SigAction>())
-        }
-    }
-}
-
-impl DerefMut for SigAction {
-    fn deref_mut(&mut self) -> &mut [u8] {
-        unsafe {
-            slice::from_raw_parts_mut(self as *mut SigAction as *mut u8,
-                                      mem::size_of::<SigAction>())
-        }
-    }
-}
-
-#[allow(dead_code)]
-unsafe fn _assert_size_of_function_is_sane() {
-    // Transmuting will complain *at compile time* if sizes differ.
-    // Rust forbids a fn-pointer from being 0 so to allow SIG_DFL to
-    // exist, we use Option<extern "C" fn(usize)> which will mean 0
-    // becomes None
-    let _ = mem::transmute::<Option<extern "C" fn(usize)>, usize>(None);
-}
-
 #[derive(Copy, Clone, Debug, Default, PartialEq)]
 #[repr(C)]
 pub struct Stat {
@@ -396,7 +361,7 @@ pub struct Sigcontrol {
     // composed of [lo pend|lo mask, hi pend|hi mask]
     pub word: [AtomicU64; 2],
 
-    pub control: SyncUnsafeCell<usize>,
+    pub control_flags: SyncUnsafeCell<SigcontrolFlags>,
 
     pub saved_scratch_a: SyncUnsafeCell<usize>,
     pub saved_scratch_b: SyncUnsafeCell<usize>,

src/flag.rs

@@ -257,26 +257,6 @@ pub const SIGIO: usize =    29;
 pub const SIGPWR: usize =   30;
 pub const SIGSYS: usize =   31;
 
-pub const SIG_DFL: usize = 0;
-pub const SIG_IGN: usize = 1;
-
-pub const SIG_BLOCK: usize = 0;
-pub const SIG_UNBLOCK: usize = 1;
-pub const SIG_SETMASK: usize = 2;
-
-bitflags! {
-    pub struct SigActionFlags: usize {
-        const SA_NOCLDSTOP = 0x00000001;
-        const SA_NOCLDWAIT = 0x00000002;
-        const SA_SIGINFO =   0x00000004;
-        const SA_RESTORER =  0x04000000;
-        const SA_ONSTACK =   0x08000000;
-        const SA_RESTART =   0x10000000;
-        const SA_NODEFER =   0x40000000;
-        const SA_RESETHAND = 0x80000000;
-    }
-}
-
 bitflags! {
     pub struct WaitFlags: usize {
         const WNOHANG =    0x01;
@@ -345,3 +325,11 @@ bitflags! {
         // TODO: O_DIRECT?
     }
 }
+bitflags! {
+    pub struct SigcontrolFlags: usize {
+        /// Prevents the kernel from jumping the context to the signal trampoline, but otherwise
+        /// has absolutely no effect on which signals are blocked etc. Meant to be used for
+        /// short-lived critical sections inside libc.
+        const INHIBIT_DELIVERY = 1;
+    }
+}