8128: Add runtime tokens for containers, and locks for multiple dispatchers

[arvados.git] / services / keepstore / volume_unix.go

diff --git a/services/keepstore/volume_unix.go b/services/keepstore/volume_unix.go
index 996068cf3d2438f71364b0b2c9ddafcdbd712c54..edec048dfe5836701f821beefdc3d7b131777982 100644 (file)
--- a/services/keepstore/volume_unix.go
+++ b/services/keepstore/volume_unix.go
@@ -181,26 +181,24 @@ func (v *UnixVolume) stat(path string) (os.FileInfo, error) {
        return stat, err
 }
 
-// Get retrieves a block identified by the locator string "loc", and
-// returns its contents as a byte slice.
-//
-// Get returns a nil buffer IFF it returns a non-nil error.
-func (v *UnixVolume) Get(loc string) ([]byte, error) {
+// Get retrieves a block, copies it to the given slice, and returns
+// the number of bytes copied.
+func (v *UnixVolume) Get(loc string, buf []byte) (int, error) {
        path := v.blockPath(loc)
        stat, err := v.stat(path)
        if err != nil {
-               return nil, v.translateError(err)
+               return 0, v.translateError(err)
+       }
+       if stat.Size() > int64(len(buf)) {
+               return 0, TooLongError
        }
-       buf := bufs.Get(int(stat.Size()))
+       var read int
+       size := int(stat.Size())
        err = v.getFunc(path, func(rdr io.Reader) error {
-               _, err = io.ReadFull(rdr, buf)
+               read, err = io.ReadFull(rdr, buf[:size])
                return err
        })
-       if err != nil {
-               bufs.Put(buf)
-               return nil, err
-       }
-       return buf, nil
+       return read, err
 }
 
 // Compare returns nil if Get(loc) would return the same content as