1 files changed, 26 insertions, 0 deletions
diff --git a/kernel/sysproc.c b/kernel/sysproc.c
index bd9d0f0..fac1d83 100644
--- a/kernel/sysproc.c
+++ b/kernel/sysproc.c
@@ -65,6 +65,9 @@ sys_sleep(void)
     }
     sleep(&ticks, &tickslock);
   }
+
+  backtrace();
+
   release(&tickslock);
   return 0;
 }
@@ -124,3 +127,26 @@ sys_sysinfo(void)
   return sys_info(si);
 }
 
+uint64
+sys_sigalarm(void)
+{
+  struct proc *p = myproc();
+  uint64 handler;
+
+  argint(0, &p->alarm_interval);
+  argaddr(1, &handler);
+  p->alarm_handler = handler;
+
+  return 0;
+}
+
+uint64 sys_sigreturn(void)
+{
+  struct proc *p = myproc();
+  // retore saved trapframe to resume
+  memmove(p->trapframe, p->atpfm, sizeof(struct trapframe));
+  p->alarm_tickspassed = 0;
+  p->alarm_caninvoke = 1;
+  // make sure return the original a0 in trapframe to pass test3
+  return p->trapframe->a0;
+}