diff --git a/wal/wal.go b/wal/wal.go index 2cac25c1c904..598e565e530a 100644 --- a/wal/wal.go +++ b/wal/wal.go @@ -157,6 +157,47 @@ func Create(dirpath string, metadata []byte) (*WAL, error) { return w, nil } +func (w *WAL) renameWal(tmpdirpath string) (*WAL, error) { + if err := os.RemoveAll(w.dir); err != nil { + return nil, err + } + // On non-Windows platforms, hold the lock while renaming. Releasing + // the lock and trying to reacquire it quickly can be flaky because + // it's possible the process will fork to spawn a process while this is + // happening. The fds are set up as close-on-exec by the Go runtime, + // but there is a window between the fork and the exec where another + // process holds the lock. + if err := os.Rename(tmpdirpath, w.dir); err != nil { + if err == os.ErrPermission { + return w.renameWalUnlock(tmpdirpath) + } + return nil, err + } + w.fp = newFilePipeline(w.dir, SegmentSizeBytes) + df, err := fileutil.OpenDir(w.dir) + w.dirFile = df + return w, err +} + +func (w *WAL) renameWalUnlock(tmpdirpath string) (*WAL, error) { + // rename of directory with locked files doesn't work on windows/cifs; + // close the WAL to release the locks so the directory can be renamed. + w.Close() + if err := os.Rename(tmpdirpath, w.dir); err != nil { + return nil, err + } + // reopen and relock + newWAL, oerr := Open(w.dir, walpb.Snapshot{}) + if oerr != nil { + return nil, oerr + } + if _, _, _, err := newWAL.ReadAll(); err != nil { + newWAL.Close() + return nil, err + } + return newWAL, nil +} + // Open opens the WAL at the given snap. // The snap SHOULD have been previously saved to the WAL, or the following // ReadAll will fail. diff --git a/wal/wal_unix.go b/wal/wal_unix.go deleted file mode 100644 index 82fd6a17a741..000000000000 --- a/wal/wal_unix.go +++ /dev/null @@ -1,44 +0,0 @@ -// Copyright 2016 The etcd Authors -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -// +build !windows - -package wal - -import ( - "os" - - "github.com/coreos/etcd/pkg/fileutil" -) - -func (w *WAL) renameWal(tmpdirpath string) (*WAL, error) { - // On non-Windows platforms, hold the lock while renaming. Releasing - // the lock and trying to reacquire it quickly can be flaky because - // it's possible the process will fork to spawn a process while this is - // happening. The fds are set up as close-on-exec by the Go runtime, - // but there is a window between the fork and the exec where another - // process holds the lock. - - if err := os.RemoveAll(w.dir); err != nil { - return nil, err - } - if err := os.Rename(tmpdirpath, w.dir); err != nil { - return nil, err - } - - w.fp = newFilePipeline(w.dir, SegmentSizeBytes) - df, err := fileutil.OpenDir(w.dir) - w.dirFile = df - return w, err -} diff --git a/wal/wal_windows.go b/wal/wal_windows.go deleted file mode 100644 index 0b9e434cf546..000000000000 --- a/wal/wal_windows.go +++ /dev/null @@ -1,41 +0,0 @@ -// Copyright 2016 The etcd Authors -// -// Licensed under the Apache License, Version 2.0 (the "License"); -// you may not use this file except in compliance with the License. -// You may obtain a copy of the License at -// -// http://www.apache.org/licenses/LICENSE-2.0 -// -// Unless required by applicable law or agreed to in writing, software -// distributed under the License is distributed on an "AS IS" BASIS, -// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. -// See the License for the specific language governing permissions and -// limitations under the License. - -package wal - -import ( - "os" - - "github.com/coreos/etcd/wal/walpb" -) - -func (w *WAL) renameWal(tmpdirpath string) (*WAL, error) { - // rename of directory with locked files doesn't work on - // windows; close the WAL to release the locks so the directory - // can be renamed - w.Close() - if err := os.Rename(tmpdirpath, w.dir); err != nil { - return nil, err - } - // reopen and relock - newWAL, oerr := Open(w.dir, walpb.Snapshot{}) - if oerr != nil { - return nil, oerr - } - if _, _, _, err := newWAL.ReadAll(); err != nil { - newWAL.Close() - return nil, err - } - return newWAL, nil -}