errors

libuwuc/src/error.rs

@@ -17,6 +17,37 @@ pub fn set_errno(errno: i32) {
     unsafe { ERRNO.0.get().write(errno) }
 }
 
+pub trait IntoOkOrErrno {
+    type Int: ReturnInt;
+    fn into_ok_or_errno(self) -> Self::Int;
+}
+
+impl<T: ReturnInt> IntoOkOrErrno for Result<T, i32> {
+    type Int = T;
+    fn into_ok_or_errno(self) -> Self::Int {
+        self.unwrap_or_else(|err| {
+            set_errno(err);
+            T::negative_one()
+        })
+    }
+}
+
+pub trait ReturnInt {
+    fn negative_one() -> Self;
+}
+
+macro_rules! return_int_impl_s {
+    ($($ty:ty)*) => {
+        $(impl ReturnInt for $ty {
+            fn negative_one() -> Self {
+                -1
+            }
+        })*
+    };
+}
+
+return_int_impl_s!(i8 i16 i32 i64 isize);
+
 pub const EPERM: i32 = 1; /* Operation not permitted */
 pub const ENOENT: i32 = 2; /* No such file or directory */
 pub const ESRCH: i32 = 3; /* No such process */

rawc/src/stdio.rs

@@ -3,6 +3,7 @@ use core::ffi::{c_char, c_int};
 use libuwuc::{
     io::{stream::FileStream, traits::WriteCounter, STDERR, STDIN, STDOUT},
     utils::SharedThinCstr,
+    error::IntoOkOrErrno
 };
 
 #[no_mangle]
@@ -22,10 +23,7 @@ pub unsafe extern "C" fn __printf_chk(_flag: c_int, format: *const u8, mut args:
         args.as_va_list(),
     );
 
-    match result {
-        Ok(()) => sink.1 as _,
-        Err(err) => err,
-    }
+    result.map(|()| sink.1 as i32).into_ok_or_errno()
 }
 
 #[no_mangle]
@@ -38,10 +36,7 @@ pub unsafe extern "C" fn printf(format: *const u8, mut args: ...) -> c_int {
         args.as_va_list(),
     );
 
-    match result {
-        Ok(()) => sink.1 as _,
-        Err(err) => err,
-    }
+    result.map(|()| sink.1 as i32).into_ok_or_errno()
 }
 
 #[no_mangle]
@@ -59,10 +54,7 @@ pub unsafe extern "C" fn __fprintf_chk(
         args.as_va_list(),
     );
 
-    match result {
-        Ok(()) => sink.1 as _,
-        Err(err) => err,
-    }
+    result.map(|()| sink.1 as i32).into_ok_or_errno()
 }
 
 #[no_mangle]
@@ -75,10 +67,7 @@ pub unsafe extern "C" fn fprintf(file: &FileStream, format: *const u8, mut args:
         args.as_va_list(),
     );
 
-    match result {
-        Ok(()) => sink.1 as _,
-        Err(err) => err,
-    }
+    result.map(|()| sink.1 as i32).into_ok_or_errno()
 }
 
 // STREAMS: