Switch PalPtrace to Rusty error handling.

src/header/sys_ptrace/mod.rs

@@ -1,6 +1,9 @@
 //! ptrace compatibility layer for Redox OS
 
-use crate::platform::{types::*, PalPtrace, Sys};
+use crate::{
+    error::ResultExt,
+    platform::{types::*, PalPtrace, Sys},
+};
 use core::ffi::VaList;
 
 pub const PTRACE_TRACEME: c_int = 0;
@@ -25,5 +28,5 @@ pub const PTRACE_SYSEMU_SINGLESTEP: c_int = 32;
 #[no_mangle]
 pub unsafe extern "C" fn ptrace(request: c_int, mut __valist: ...) -> c_int {
     // Musl also just grabs the arguments from the varargs...
-    Sys::ptrace(request, __valist.arg(), __valist.arg(), __valist.arg())
+    Sys::ptrace(request, __valist.arg(), __valist.arg(), __valist.arg()).or_minus_one_errno()
 }

src/platform/linux/ptrace.rs

@@ -1,10 +1,16 @@
 use super::{
     super::{types::*, PalPtrace},
-    e, Sys,
+    e_raw, Sys,
 };
+use crate::error::Result;
 
 impl PalPtrace for Sys {
-    fn ptrace(request: c_int, pid: pid_t, addr: *mut c_void, data: *mut c_void) -> c_int {
-        unsafe { e(syscall!(PTRACE, request, pid, addr, data)) as c_int }
+    unsafe fn ptrace(
+        request: c_int,
+        pid: pid_t,
+        addr: *mut c_void,
+        data: *mut c_void,
+    ) -> Result<c_int> {
+        Ok(unsafe { e_raw(syscall!(PTRACE, request, pid, addr, data))? as c_int })
     }
 }

src/platform/pal/ptrace.rs

@@ -1,5 +1,13 @@
-use super::super::{types::*, Pal};
+use crate::{
+    error::Result,
+    platform::{types::*, Pal},
+};
 
 pub trait PalPtrace: Pal {
-    fn ptrace(request: c_int, pid: pid_t, addr: *mut c_void, data: *mut c_void) -> c_int;
+    unsafe fn ptrace(
+        request: c_int,
+        pid: pid_t,
+        addr: *mut c_void,
+        data: *mut c_void,
+    ) -> Result<c_int>;
 }

src/platform/redox/ptrace.rs

@@ -11,8 +11,12 @@ use crate::header::arch_aarch64_user::user_regs_struct;
 use crate::header::arch_x64_user::user_regs_struct;
 use crate::{
     c_str::{CStr, CString},
+    error::Errno,
     fs::File,
-    header::{errno as errnoh, fcntl, signal, sys_ptrace},
+    header::{
+        errno::{self as errnoh, EIO},
+        fcntl, signal, sys_ptrace,
+    },
     io::{self, prelude::*},
     sync::Mutex,
 };
@@ -104,7 +108,7 @@ pub fn get_session(
 }
 
 #[cfg(target_arch = "aarch64")]
-fn inner_ptrace(
+unsafe fn inner_ptrace(
     request: c_int,
     pid: pid_t,
     addr: *mut c_void,
@@ -115,7 +119,7 @@ fn inner_ptrace(
 }
 
 #[cfg(target_arch = "x86")]
-fn inner_ptrace(
+unsafe fn inner_ptrace(
     request: c_int,
     pid: pid_t,
     addr: *mut c_void,
@@ -126,7 +130,7 @@ fn inner_ptrace(
 }
 
 #[cfg(target_arch = "x86_64")]
-fn inner_ptrace(
+unsafe fn inner_ptrace(
     request: c_int,
     pid: pid_t,
     addr: *mut c_void,
@@ -253,7 +257,13 @@ fn inner_ptrace(
 }
 
 impl PalPtrace for Sys {
-    fn ptrace(request: c_int, pid: pid_t, addr: *mut c_void, data: *mut c_void) -> c_int {
-        inner_ptrace(request, pid, addr, data).unwrap_or(-1)
+    unsafe fn ptrace(
+        request: c_int,
+        pid: pid_t,
+        addr: *mut c_void,
+        data: *mut c_void,
+    ) -> Result<c_int, Errno> {
+        inner_ptrace(request, pid, addr, data)
+            .map_err(|err| Errno(err.raw_os_error().unwrap_or(EIO)))
     }
 }