publish semacquire and semrelease for use by sync.

more enforcing package boundaries

R=r
DELTA=46  (13 added, 15 deleted, 18 changed)
OCL=35806
CL=35806

2 files changed, 14 insertions, 3 deletions

diff --git a/src/pkg/runtime/extern.go b/src/pkg/runtime/extern.go
index 131767aef..70c6f434b 100644
--- a/src/pkg/runtime/extern.go
+++ b/src/pkg/runtime/extern.go
@@ -46,3 +46,14 @@ func GOMAXPROCS(n int)
 
 // Cgocalls returns the number of cgo calls made by the current process.
 func Cgocalls() int64
+
+// Semacquire waits until *s > 0 and then atomically decrements it.
+// It is intended as a simple sleep primitive for use by the synchronization
+// library and should not be used directly.
+func Semacquire(s *uint32)
+
+// Semrelease atomically increments *s and notifies a waiting goroutine
+// if one is blocked in Semacquire.
+// It is intended as a simple wakeup primitive for use by the synchronization
+// library and should not be used directly.
+func Semrelease(s *uint32)
diff --git a/src/pkg/runtime/sema.cgo b/src/pkg/runtime/sema.cgo
index 81834ae6d..71395ce77 100644
--- a/src/pkg/runtime/sema.cgo
+++ b/src/pkg/runtime/sema.cgo
@@ -17,7 +17,7 @@
 // See Mullender and Cox, ``Semaphores in Plan 9,''
 // http://swtch.com/semaphore.pdf
 
-package sync
+package runtime
 #include "runtime.h"
 
 typedef struct Sema Sema;
@@ -176,10 +176,10 @@ semrelease(uint32 *addr)
 	semwakeup(addr);
 }
 
-func semacquire(addr *uint32) {
+func Semacquire(addr *uint32) {
 	semacquire(addr);
 }
 
-func semrelease(addr *uint32) {
+func Semrelease(addr *uint32) {
 	semrelease(addr);
 }