Move pkg/gate to pkg/syncutil, to house more stuff.

Change-Id: I737458641a9de03da55ed627bfac10f3377a13aa

cmd/camput/camput.go

@@ -28,8 +28,8 @@ import (
 
 	"camlistore.org/pkg/client"
 	"camlistore.org/pkg/cmdmain"
-	"camlistore.org/pkg/gate"
 	"camlistore.org/pkg/httputil"
+	"camlistore.org/pkg/syncutil"
 )
 
 const buffered = 16 // arbitrary
@@ -128,7 +128,7 @@ func newUploader() *Uploader {
 		Client:    cc,
 		transport: httpStats,
 		pwd:       pwd,
-		fdGate:    gate.New(100), // gate things that waste fds, assuming a low system limit
+		fdGate:    syncutil.NewGate(100), // gate things that waste fds, assuming a low system limit
 	}
 }
 

cmd/camput/uploader.go

@@ -22,15 +22,15 @@ import (
 
 	"camlistore.org/pkg/blobserver"
 	"camlistore.org/pkg/client"
-	"camlistore.org/pkg/gate"
 	"camlistore.org/pkg/httputil"
+	"camlistore.org/pkg/syncutil"
 )
 
 type Uploader struct {
 	*client.Client
 
 	// fdGate guards gates the creation of file descriptors.
-	fdGate *gate.Gate
+	fdGate *syncutil.Gate
 
 	fileOpts *fileOptions // per-file options; may be nil
 

pkg/blobserver/localdisk/stat.go

@@ -20,7 +20,7 @@ import (
 	"os"
 
 	"camlistore.org/pkg/blob"
-	"camlistore.org/pkg/gate"
+	"camlistore.org/pkg/syncutil"
 )
 
 const maxParallelStats = 20
@@ -48,7 +48,7 @@ func (ds *DiskStorage) StatBlobs(dest chan<- blob.SizedRef, blobs []blob.Ref) er
 
 	errc := make(chan error, len(blobs))
 
-	gt := gate.New(maxParallelStats)
+	gt := syncutil.NewGate(maxParallelStats)
 	for _, ref := range blobs {
 		gt.Start()
 		go func(ref blob.Ref) {

pkg/blobserver/s3/stat.go

@@ -21,10 +21,10 @@ import (
 	"os"
 
 	"camlistore.org/pkg/blob"
-	"camlistore.org/pkg/gate"
+	"camlistore.org/pkg/syncutil"
 )
 
-var statGate = gate.New(20) // arbitrary
+var statGate = syncutil.NewGate(20) // arbitrary
 
 func (sto *s3Storage) StatBlobs(dest chan<- blob.SizedRef, blobs []blob.Ref) error {
 	errc := make(chan error, len(blobs))

pkg/schema/filewriter.go

@@ -26,8 +26,8 @@ import (
 
 	"camlistore.org/pkg/blob"
 	"camlistore.org/pkg/blobserver"
-	"camlistore.org/pkg/gate"
 	"camlistore.org/pkg/rollsum"
+	"camlistore.org/pkg/syncutil"
 )
 
 const (
@@ -340,7 +340,7 @@ func writeFileChunks(bs blobserver.StatReceiver, file *Builder, r io.Reader) (n
 	blobSize := 0 // of the next blob being built, should be same as buf.Len()
 
 	const chunksInFlight = 32 // at ~64 KB chunks, this is ~2MB memory per file
-	gatec := gate.New(chunksInFlight)
+	gatec := syncutil.NewGate(chunksInFlight)
 	firsterrc := make(chan error, 1)
 
 	// uploadLastSpan runs in the same goroutine as the loop below and is responsible for

pkg/syncutil/gate.go

@@ -14,17 +14,16 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-// Package gate provides a mechanism to control a maximum number of
-// operations happening at once.
-package gate
+// Package syncutil provides various concurrency mechanisms.
+package syncutil
 
 // A Gate limits concurrency.
 type Gate struct {
 	c chan struct{}
 }
 
-// New returns a new gate that will only permit max operations at once.
-func New(max int) *Gate {
+// NewGate returns a new gate that will only permit max operations at once.
+func NewGate(max int) *Gate {
 	return &Gate{make(chan struct{}, max)}
 }