Rollup merge of #136844 - thaliaarchi:const-io-error, r=ChrisDenton

Use `const_error!` when possible

Replace usages of `io::Error::new(io::ErrorKind::Variant, "constant string")` with `io::const_error!(io::ErrorKind::Variant, "constant string")` to avoid allocations when possible. Additionally, fix `&&str` error messages in SGX and missing/misplaced trailing commas in `const_error!`.

4 files changed, 61 insertions, 66 deletions

diff --git a/library/std/src/sys/net/connection/xous/dns.rs b/library/std/src/sys/net/connection/xous/dns.rs
index ff6e49ed2d4..bb29d211fad 100644
--- a/library/std/src/sys/net/connection/xous/dns.rs
+++ b/library/std/src/sys/net/connection/xous/dns.rs
@@ -123,6 +123,6 @@ impl TryFrom<(&str, u16)> for LookupHost {
     type Error = io::Error;
 
     fn try_from(v: (&str, u16)) -> io::Result<LookupHost> {
-        lookup(v.0, v.1).map_err(|_e| io::const_error!(io::ErrorKind::InvalidInput, &"DNS failure"))
+        lookup(v.0, v.1).map_err(|_e| io::const_error!(io::ErrorKind::InvalidInput, "DNS failure"))
     }
 }
diff --git a/library/std/src/sys/net/connection/xous/tcplistener.rs b/library/std/src/sys/net/connection/xous/tcplistener.rs
index 640a02a64f5..851d2eb8178 100644
--- a/library/std/src/sys/net/connection/xous/tcplistener.rs
+++ b/library/std/src/sys/net/connection/xous/tcplistener.rs
@@ -11,7 +11,7 @@ macro_rules! unimpl {
     () => {
         return Err(io::const_error!(
             io::ErrorKind::Unsupported,
-            &"This function is not yet implemented",
+            "This function is not yet implemented",
         ));
     };
 }
@@ -71,7 +71,7 @@ impl TcpListener {
             0,
             4096,
         ) else {
-            return Err(io::const_error!(io::ErrorKind::InvalidInput, &"Invalid response"));
+            return Err(io::const_error!(io::ErrorKind::InvalidInput, "Invalid response"));
         };
 
         // The first four bytes should be zero upon success, and will be nonzero
@@ -80,15 +80,15 @@ impl TcpListener {
         if response[0] != 0 || valid == 0 {
             let errcode = response[1];
             if errcode == NetError::SocketInUse as u8 {
-                return Err(io::const_error!(io::ErrorKind::ResourceBusy, &"Socket in use"));
+                return Err(io::const_error!(io::ErrorKind::ResourceBusy, "Socket in use"));
             } else if errcode == NetError::Invalid as u8 {
-                return Err(io::const_error!(io::ErrorKind::AddrNotAvailable, &"Invalid address"));
+                return Err(io::const_error!(io::ErrorKind::AddrNotAvailable, "Invalid address"));
             } else if errcode == NetError::LibraryError as u8 {
-                return Err(io::const_error!(io::ErrorKind::Other, &"Library error"));
+                return Err(io::const_error!(io::ErrorKind::Other, "Library error"));
             } else {
                 return Err(io::const_error!(
                     io::ErrorKind::Other,
-                    &"Unable to connect or internal error"
+                    "Unable to connect or internal error",
                 ));
             }
         }
@@ -127,15 +127,13 @@ impl TcpListener {
             if receive_request.raw[0] != 0 {
                 // error case
                 if receive_request.raw[1] == NetError::TimedOut as u8 {
-                    return Err(io::const_error!(io::ErrorKind::TimedOut, &"accept timed out",));
+                    return Err(io::const_error!(io::ErrorKind::TimedOut, "accept timed out"));
                 } else if receive_request.raw[1] == NetError::WouldBlock as u8 {
-                    return Err(
-                        io::const_error!(io::ErrorKind::WouldBlock, &"accept would block",),
-                    );
+                    return Err(io::const_error!(io::ErrorKind::WouldBlock, "accept would block"));
                 } else if receive_request.raw[1] == NetError::LibraryError as u8 {
-                    return Err(io::const_error!(io::ErrorKind::Other, &"Library error"));
+                    return Err(io::const_error!(io::ErrorKind::Other, "Library error"));
                 } else {
-                    return Err(io::const_error!(io::ErrorKind::Other, &"library error",));
+                    return Err(io::const_error!(io::ErrorKind::Other, "library error"));
                 }
             } else {
                 // accept successful
@@ -159,7 +157,7 @@ impl TcpListener {
                         port,
                     )
                 } else {
-                    return Err(io::const_error!(io::ErrorKind::Other, &"library error",));
+                    return Err(io::const_error!(io::ErrorKind::Other, "library error"));
                 };
 
                 // replenish the listener
@@ -171,7 +169,7 @@ impl TcpListener {
                 Ok((TcpStream::from_listener(stream_fd, self.local.port(), port, addr), addr))
             }
         } else {
-            Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unable to accept"))
+            Err(io::const_error!(io::ErrorKind::InvalidInput, "Unable to accept"))
         }
     }
 
@@ -182,13 +180,13 @@ impl TcpListener {
 
     pub fn set_ttl(&self, ttl: u32) -> io::Result<()> {
         if ttl > 255 {
-            return Err(io::Error::new(io::ErrorKind::InvalidInput, "TTL must be less than 256"));
+            return Err(io::const_error!(io::ErrorKind::InvalidInput, "TTL must be less than 256"));
         }
         crate::os::xous::ffi::blocking_scalar(
             services::net_server(),
             services::NetBlockingScalar::StdSetTtlTcp(self.fd.load(Ordering::Relaxed), ttl).into(),
         )
-        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, "Unexpected return value")))
         .map(|_| ())
     }
 
@@ -197,7 +195,7 @@ impl TcpListener {
             services::net_server(),
             services::NetBlockingScalar::StdGetTtlTcp(self.fd.load(Ordering::Relaxed)).into(),
         )
-        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, "Unexpected return value")))
         .map(|res| res[0] as _)?)
     }
 
diff --git a/library/std/src/sys/net/connection/xous/tcpstream.rs b/library/std/src/sys/net/connection/xous/tcpstream.rs
index 572dd6b3b63..7f7bbfb7fed 100644
--- a/library/std/src/sys/net/connection/xous/tcpstream.rs
+++ b/library/std/src/sys/net/connection/xous/tcpstream.rs
@@ -12,7 +12,7 @@ macro_rules! unimpl {
     () => {
         return Err(io::const_error!(
             io::ErrorKind::Unsupported,
-            &"This function is not yet implemented",
+            "This function is not yet implemented",
         ));
     };
 }
@@ -96,7 +96,7 @@ impl TcpStream {
             0,
             4096,
         ) else {
-            return Err(io::const_error!(io::ErrorKind::InvalidInput, &"Invalid response"));
+            return Err(io::const_error!(io::ErrorKind::InvalidInput, "Invalid response"));
         };
 
         // The first four bytes should be zero upon success, and will be nonzero
@@ -106,13 +106,13 @@ impl TcpStream {
             // errcode is a u8 but stuck in a u16 where the upper byte is invalid. Mask & decode accordingly.
             let errcode = response[0];
             if errcode == NetError::SocketInUse as u8 {
-                return Err(io::const_error!(io::ErrorKind::ResourceBusy, &"Socket in use",));
+                return Err(io::const_error!(io::ErrorKind::ResourceBusy, "Socket in use"));
             } else if errcode == NetError::Unaddressable as u8 {
-                return Err(io::const_error!(io::ErrorKind::AddrNotAvailable, &"Invalid address",));
+                return Err(io::const_error!(io::ErrorKind::AddrNotAvailable, "Invalid address"));
             } else {
                 return Err(io::const_error!(
                     io::ErrorKind::InvalidInput,
-                    &"Unable to connect or internal error",
+                    "Unable to connect or internal error",
                 ));
             }
         }
@@ -198,7 +198,7 @@ impl TcpStream {
         ) else {
             return Err(io::const_error!(
                 io::ErrorKind::InvalidInput,
-                &"Library failure: wrong message type or messaging error"
+                "Library failure: wrong message type or messaging error",
             ));
         };
 
@@ -212,14 +212,14 @@ impl TcpStream {
             if result[0] != 0 {
                 if result[1] == 8 {
                     // timed out
-                    return Err(io::const_error!(io::ErrorKind::TimedOut, &"Timeout",));
+                    return Err(io::const_error!(io::ErrorKind::TimedOut, "Timeout"));
                 }
                 if result[1] == 9 {
                     // would block
-                    return Err(io::const_error!(io::ErrorKind::WouldBlock, &"Would block",));
+                    return Err(io::const_error!(io::ErrorKind::WouldBlock, "Would block"));
                 }
             }
-            Err(io::const_error!(io::ErrorKind::Other, &"recv_slice failure"))
+            Err(io::const_error!(io::ErrorKind::Other, "recv_slice failure"))
         }
     }
 
@@ -258,20 +258,20 @@ impl TcpStream {
             self.write_timeout.load(Ordering::Relaxed) as usize,
             buf_len,
         )
-        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Internal error")))?;
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, "Internal error")))?;
 
         if send_request.raw[0] != 0 {
             if send_request.raw[4] == 8 {
                 // timed out
                 return Err(io::const_error!(
                     io::ErrorKind::BrokenPipe,
-                    &"Timeout or connection closed",
+                    "Timeout or connection closed",
                 ));
             } else if send_request.raw[4] == 9 {
                 // would block
-                return Err(io::const_error!(io::ErrorKind::WouldBlock, &"Would block",));
+                return Err(io::const_error!(io::ErrorKind::WouldBlock, "Would block"));
             } else {
-                return Err(io::const_error!(io::ErrorKind::InvalidInput, &"Error when sending",));
+                return Err(io::const_error!(io::ErrorKind::InvalidInput, "Error when sending"));
             }
         }
         Ok(u32::from_le_bytes([
@@ -304,7 +304,7 @@ impl TcpStream {
             0,
             0,
         ) else {
-            return Err(io::const_error!(io::ErrorKind::InvalidInput, &"Internal error"));
+            return Err(io::const_error!(io::ErrorKind::InvalidInput, "Internal error"));
         };
         let mut i = get_addr.raw.iter();
         match *i.next().unwrap() {
@@ -324,7 +324,7 @@ impl TcpStream {
                 }
                 Ok(SocketAddr::V6(SocketAddrV6::new(new_addr.into(), self.local_port, 0, 0)))
             }
-            _ => Err(io::const_error!(io::ErrorKind::InvalidInput, &"Internal error")),
+            _ => Err(io::const_error!(io::ErrorKind::InvalidInput, "Internal error")),
         }
     }
 
@@ -333,7 +333,7 @@ impl TcpStream {
             services::net_server(),
             services::NetBlockingScalar::StdTcpStreamShutdown(self.fd, how).into(),
         )
-        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, "Unexpected return value")))
         .map(|_| ())
     }
 
@@ -355,7 +355,7 @@ impl TcpStream {
             services::net_server(),
             services::NetBlockingScalar::StdSetNodelay(self.fd, enabled).into(),
         )
-        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, "Unexpected return value")))
         .map(|_| ())
     }
 
@@ -364,19 +364,19 @@ impl TcpStream {
             services::net_server(),
             services::NetBlockingScalar::StdGetNodelay(self.fd).into(),
         )
-        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, "Unexpected return value")))
         .map(|res| res[0] != 0)?)
     }
 
     pub fn set_ttl(&self, ttl: u32) -> io::Result<()> {
         if ttl > 255 {
-            return Err(io::Error::new(io::ErrorKind::InvalidInput, "TTL must be less than 256"));
+            return Err(io::const_error!(io::ErrorKind::InvalidInput, "TTL must be less than 256"));
         }
         crate::os::xous::ffi::blocking_scalar(
             services::net_server(),
             services::NetBlockingScalar::StdSetTtlTcp(self.fd, ttl).into(),
         )
-        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, "Unexpected return value")))
         .map(|_| ())
     }
 
@@ -385,7 +385,7 @@ impl TcpStream {
             services::net_server(),
             services::NetBlockingScalar::StdGetTtlTcp(self.fd).into(),
         )
-        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, "Unexpected return value")))
         .map(|res| res[0] as _)?)
     }
 
diff --git a/library/std/src/sys/net/connection/xous/udp.rs b/library/std/src/sys/net/connection/xous/udp.rs
index 1b7ecac6d3a..ab5bd357b61 100644
--- a/library/std/src/sys/net/connection/xous/udp.rs
+++ b/library/std/src/sys/net/connection/xous/udp.rs
@@ -13,7 +13,7 @@ macro_rules! unimpl {
     () => {
         return Err(io::const_error!(
             io::ErrorKind::Unsupported,
-            &"This function is not yet implemented",
+            "This function is not yet implemented",
         ));
     };
 }
@@ -72,18 +72,18 @@ impl UdpSocket {
             if response[0] != 0 || valid == 0 {
                 let errcode = response[1];
                 if errcode == NetError::SocketInUse as u8 {
-                    return Err(io::const_error!(io::ErrorKind::ResourceBusy, &"Socket in use"));
+                    return Err(io::const_error!(io::ErrorKind::ResourceBusy, "Socket in use"));
                 } else if errcode == NetError::Invalid as u8 {
                     return Err(io::const_error!(
                         io::ErrorKind::InvalidInput,
-                        &"Port can't be 0 or invalid address"
+                        "Port can't be 0 or invalid address",
                     ));
                 } else if errcode == NetError::LibraryError as u8 {
-                    return Err(io::const_error!(io::ErrorKind::Other, &"Library error"));
+                    return Err(io::const_error!(io::ErrorKind::Other, "Library error"));
                 } else {
                     return Err(io::const_error!(
                         io::ErrorKind::Other,
-                        &"Unable to connect or internal error"
+                        "Unable to connect or internal error",
                     ));
                 }
             }
@@ -98,13 +98,13 @@ impl UdpSocket {
                 nonblocking: Cell::new(false),
             });
         }
-        Err(io::const_error!(io::ErrorKind::InvalidInput, &"Invalid response"))
+        Err(io::const_error!(io::ErrorKind::InvalidInput, "Invalid response"))
     }
 
     pub fn peer_addr(&self) -> io::Result<SocketAddr> {
         match self.remote.get() {
             Some(dest) => Ok(dest),
-            None => Err(io::const_error!(io::ErrorKind::NotConnected, &"No peer specified")),
+            None => Err(io::const_error!(io::ErrorKind::NotConnected, "No peer specified")),
         }
     }
 
@@ -141,13 +141,13 @@ impl UdpSocket {
             if receive_request.raw[0] != 0 {
                 // error case
                 if receive_request.raw[1] == NetError::TimedOut as u8 {
-                    return Err(io::const_error!(io::ErrorKind::TimedOut, &"recv timed out",));
+                    return Err(io::const_error!(io::ErrorKind::TimedOut, "recv timed out"));
                 } else if receive_request.raw[1] == NetError::WouldBlock as u8 {
-                    return Err(io::const_error!(io::ErrorKind::WouldBlock, &"recv would block",));
+                    return Err(io::const_error!(io::ErrorKind::WouldBlock, "recv would block"));
                 } else if receive_request.raw[1] == NetError::LibraryError as u8 {
-                    return Err(io::const_error!(io::ErrorKind::Other, &"Library error"));
+                    return Err(io::const_error!(io::ErrorKind::Other, "Library error"));
                 } else {
-                    return Err(io::const_error!(io::ErrorKind::Other, &"library error",));
+                    return Err(io::const_error!(io::ErrorKind::Other, "library error"));
                 }
             } else {
                 let rr = &receive_request.raw;
@@ -170,7 +170,7 @@ impl UdpSocket {
                         port,
                     )
                 } else {
-                    return Err(io::const_error!(io::ErrorKind::Other, &"library error",));
+                    return Err(io::const_error!(io::ErrorKind::Other, "library error"));
                 };
                 for (&s, d) in rr[22..22 + rxlen as usize].iter().zip(buf.iter_mut()) {
                     *d = s;
@@ -178,7 +178,7 @@ impl UdpSocket {
                 Ok((rxlen as usize, addr))
             }
         } else {
-            Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unable to recv"))
+            Err(io::const_error!(io::ErrorKind::InvalidInput, "Unable to recv"))
         }
     }
 
@@ -208,7 +208,7 @@ impl UdpSocket {
         if let Some(addr) = self.remote.get() {
             self.send_to(buf, &addr)
         } else {
-            Err(io::const_error!(io::ErrorKind::NotConnected, &"No remote specified"))
+            Err(io::const_error!(io::ErrorKind::NotConnected, "No remote specified"))
         }
     }
 
@@ -281,19 +281,19 @@ impl UdpSocket {
                         if errcode == NetError::SocketInUse as u8 {
                             return Err(io::const_error!(
                                 io::ErrorKind::ResourceBusy,
-                                &"Socket in use"
+                                "Socket in use",
                             ));
                         } else if errcode == NetError::Invalid as u8 {
                             return Err(io::const_error!(
                                 io::ErrorKind::InvalidInput,
-                                &"Socket not valid"
+                                "Socket not valid",
                             ));
                         } else if errcode == NetError::LibraryError as u8 {
-                            return Err(io::const_error!(io::ErrorKind::Other, &"Library error"));
+                            return Err(io::const_error!(io::ErrorKind::Other, "Library error"));
                         } else {
                             return Err(io::const_error!(
                                 io::ErrorKind::Other,
-                                &"Unable to connect"
+                                "Unable to connect",
                             ));
                         }
                     } else {
@@ -303,16 +303,13 @@ impl UdpSocket {
                 }
                 Err(crate::os::xous::ffi::Error::ServerQueueFull) => {
                     if now.elapsed() >= write_timeout {
-                        return Err(io::const_error!(
-                            io::ErrorKind::WouldBlock,
-                            &"Write timed out"
-                        ));
+                        return Err(io::const_error!(io::ErrorKind::WouldBlock, "Write timed out"));
                     } else {
                         // question: do we want to do something a bit more gentle than immediately retrying?
                         crate::thread::yield_now();
                     }
                 }
-                _ => return Err(io::const_error!(io::ErrorKind::Other, &"Library error")),
+                _ => return Err(io::const_error!(io::ErrorKind::Other, "Library error")),
             }
         }
     }
@@ -360,13 +357,13 @@ impl UdpSocket {
 
     pub fn set_ttl(&self, ttl: u32) -> io::Result<()> {
         if ttl > 255 {
-            return Err(io::Error::new(io::ErrorKind::InvalidInput, "TTL must be less than 256"));
+            return Err(io::const_error!(io::ErrorKind::InvalidInput, "TTL must be less than 256"));
         }
         crate::os::xous::ffi::blocking_scalar(
             services::net_server(),
             services::NetBlockingScalar::StdSetTtlUdp(self.fd, ttl).into(),
         )
-        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, "Unexpected return value")))
         .map(|_| ())
     }
 
@@ -375,7 +372,7 @@ impl UdpSocket {
             services::net_server(),
             services::NetBlockingScalar::StdGetTtlUdp(self.fd).into(),
         )
-        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, &"Unexpected return value")))
+        .or(Err(io::const_error!(io::ErrorKind::InvalidInput, "Unexpected return value")))
         .map(|res| res[0] as _)?)
     }
 
@@ -441,7 +438,7 @@ impl UdpSocket {
 
 impl fmt::Debug for UdpSocket {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "UDP listening on {:?} to {:?}", self.local, self.remote.get(),)
+        write!(f, "UDP listening on {:?} to {:?}", self.local, self.remote.get())
     }
 }