Imported Upstream version 1.4upstream/1.4

1 files changed, 0 insertions, 118 deletions

diff --git a/src/pkg/sync/cond.go b/src/pkg/sync/cond.go
deleted file mode 100644
index 9e6bc170f..000000000
--- a/src/pkg/sync/cond.go
+++ /dev/null
@@ -1,118 +0,0 @@
-// Copyright 2011 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-package sync
-
-import (
-	"sync/atomic"
-	"unsafe"
-)
-
-// Cond implements a condition variable, a rendezvous point
-// for goroutines waiting for or announcing the occurrence
-// of an event.
-//
-// Each Cond has an associated Locker L (often a *Mutex or *RWMutex),
-// which must be held when changing the condition and
-// when calling the Wait method.
-//
-// A Cond can be created as part of other structures.
-// A Cond must not be copied after first use.
-type Cond struct {
-	// L is held while observing or changing the condition
-	L Locker
-
-	sema    syncSema
-	waiters uint32 // number of waiters
-	checker copyChecker
-}
-
-// NewCond returns a new Cond with Locker l.
-func NewCond(l Locker) *Cond {
-	return &Cond{L: l}
-}
-
-// Wait atomically unlocks c.L and suspends execution
-// of the calling goroutine.  After later resuming execution,
-// Wait locks c.L before returning.  Unlike in other systems,
-// Wait cannot return unless awoken by Broadcast or Signal.
-//
-// Because c.L is not locked when Wait first resumes, the caller
-// typically cannot assume that the condition is true when
-// Wait returns.  Instead, the caller should Wait in a loop:
-//
-//    c.L.Lock()
-//    for !condition() {
-//        c.Wait()
-//    }
-//    ... make use of condition ...
-//    c.L.Unlock()
-//
-func (c *Cond) Wait() {
-	c.checker.check()
-	if raceenabled {
-		raceDisable()
-	}
-	atomic.AddUint32(&c.waiters, 1)
-	if raceenabled {
-		raceEnable()
-	}
-	c.L.Unlock()
-	runtime_Syncsemacquire(&c.sema)
-	c.L.Lock()
-}
-
-// Signal wakes one goroutine waiting on c, if there is any.
-//
-// It is allowed but not required for the caller to hold c.L
-// during the call.
-func (c *Cond) Signal() {
-	c.signalImpl(false)
-}
-
-// Broadcast wakes all goroutines waiting on c.
-//
-// It is allowed but not required for the caller to hold c.L
-// during the call.
-func (c *Cond) Broadcast() {
-	c.signalImpl(true)
-}
-
-func (c *Cond) signalImpl(all bool) {
-	c.checker.check()
-	if raceenabled {
-		raceDisable()
-	}
-	for {
-		old := atomic.LoadUint32(&c.waiters)
-		if old == 0 {
-			if raceenabled {
-				raceEnable()
-			}
-			return
-		}
-		new := old - 1
-		if all {
-			new = 0
-		}
-		if atomic.CompareAndSwapUint32(&c.waiters, old, new) {
-			if raceenabled {
-				raceEnable()
-			}
-			runtime_Syncsemrelease(&c.sema, old-new)
-			return
-		}
-	}
-}
-
-// copyChecker holds back pointer to itself to detect object copying.
-type copyChecker uintptr
-
-func (c *copyChecker) check() {
-	if uintptr(*c) != uintptr(unsafe.Pointer(c)) &&
-		!atomic.CompareAndSwapUintptr((*uintptr)(c), 0, uintptr(unsafe.Pointer(c))) &&
-		uintptr(*c) != uintptr(unsafe.Pointer(c)) {
-		panic("sync.Cond is copied")
-	}
-}