code review 5334051: runtime: add timer support, use for package time

src/pkg/runtime/freebsd/thread.c

 // Use of this source file is governed by a BSD-style
 // license that can be found in the LICENSE file.`
 
 #include "runtime.h"
 #include "defs.h"
 #include "os.h"
 #include "stack.h"
 
 extern SigTab runtime·sigtab[];
 extern int32 runtime·sys_umtx_op(uint32*, int32, uint32, void*, void*);
 
 // FreeBSD's umtx_op syscall is effectively the same as Linux's futex, and
-// thus the code is largely similar. See linux/thread.c for comments.
+// thus the code is largely similar. See linux/thread.c and lock_futex.c for comments.
 
 void
-runtime·futexsleep(uint32 *addr, uint32 val)
+runtime·futexsleep(uint32 *addr, uint32 val, int64 ns)
 {
         int32 ret;
+        Timespec ts, *tsp;
 
-        ret = runtime·sys_umtx_op(addr, UMTX_OP_WAIT, val, nil, nil);
+        if(ns < 0)
+                tsp = nil;
+        else {
+                ts.sec = ns / 1000000000LL;
+                ts.nsec = ns % 1000000000LL;
+                tsp = &ts;
+        }
+
+        ret = runtime·sys_umtx_op(addr, UMTX_OP_WAIT, val, nil, tsp);
         if(ret >= 0 || ret == -EINTR)
                 return;
 
         runtime·printf("umtx_wait addr=%p val=%d ret=%d\n", addr, val, ret);
         *(int32*)0x1005 = 0x1005;
 }
 
 void
 runtime·futexwakeup(uint32 *addr, uint32 cnt)
 {
@@ skipping 82 matching lines @@
                 runtime·panicstring("floating point error");
         }
         runtime·panicstring(runtime·sigtab[g->sig].name);
 }
 
 // TODO: fill this in properly.
 void
 runtime·osyield(void)
 {
 }