eintr: support for blocking syscall INTR (interrupted) mode

kernel/src/managers/interrupt/interrupt.c

@@ -48,7 +48,7 @@ stack_frame_t *userisr_handler(stack_frame_t *frame, int IRQn)
          * function only if needed
          */
         mgr_time_delay_del_job(owner);
-        mgr_task_set_sysreturn(owner, STATUS_OK);
+        mgr_task_set_sysreturn(owner, STATUS_INTR);
         mgr_task_set_state(owner, JOB_STATE_READY);
         sched_schedule(owner);
     }

kernel/src/syscalls/sysgate_send_ipc.c

@@ -45,8 +45,7 @@ stack_frame_t *gate_send_ipc(stack_frame_t *frame, taskh_t target, uint32_t len)
          * function only if needed
          */
         mgr_time_delay_del_job(target);
-        /* FIXME: define a dedicated return code */
-        mgr_task_set_sysreturn(target, STATUS_OK);
+        mgr_task_set_sysreturn(target, STATUS_INTR);
         mgr_task_set_state(target, JOB_STATE_READY);
         sched_schedule(target);
     }

kernel/src/syscalls/sysgate_send_signal.c

@@ -47,7 +47,7 @@ stack_frame_t *gate_send_signal(stack_frame_t *frame,
          */
         mgr_time_delay_del_job(target);
         /* FIXME: define a dedicated return code */
-        mgr_task_set_sysreturn(target, STATUS_OK);
+        mgr_task_set_sysreturn(target, STATUS_INTR);
         mgr_task_set_state(target, JOB_STATE_READY);
         sched_schedule(target);
     }

uapi/include/uapi/types.h

@@ -203,6 +203,7 @@ typedef enum Status {
   STATUS_CRITICAL,
   STATUS_TIMEOUT,
   STATUS_AGAIN,
+  STATUS_INTR,
   STATUS_NON_SENSE,
 } Status;
 

uapi/uapi/syscall.rs

@@ -219,7 +219,10 @@ pub extern "C" fn sys_irq_disable(irq: u16) -> Status {
 /// POSIX upper layer(s): select(2), poll(2)
 #[no_mangle]
 pub extern "C" fn sys_wait_for_event(mask: u8, timeout: i32) -> Status {
-    syscall!(Syscall::WaitForEvent, u32::from(mask), timeout).into()
+    match syscall!(Syscall::WaitForEvent, u32::from(mask), timeout).into() {
+        Status::Intr => syscall!(Syscall::WaitForEvent, u32::from(mask), timeout).into(),
+        any => return any,
+    }
 }
 
 /// Configure the CPU's sleep behaviour.

uapi/uapi/systypes.rs

@@ -126,6 +126,7 @@ pub enum Status {
     Critical,
     Timeout,
     Again,
+    Intr,
 }
 
 impl From<u32> for Status {
@@ -141,6 +142,7 @@ impl From<u32> for Status {
             7 => Status::Critical,
             8 => Status::Timeout,
             9 => Status::Again,
+            10 => Status::Intr,
             _ => panic!(),
         }
     }