diff options
Diffstat (limited to 'vendor/github.com/containerd/continuity/fs/copy.go')
-rw-r--r-- | vendor/github.com/containerd/continuity/fs/copy.go | 172 |
1 files changed, 172 insertions, 0 deletions
diff --git a/vendor/github.com/containerd/continuity/fs/copy.go b/vendor/github.com/containerd/continuity/fs/copy.go new file mode 100644 index 000000000..ad61022ad --- /dev/null +++ b/vendor/github.com/containerd/continuity/fs/copy.go @@ -0,0 +1,172 @@ +/* + Copyright The containerd 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 fs + +import ( + "io/ioutil" + "os" + "path/filepath" + "sync" + + "github.com/pkg/errors" +) + +var bufferPool = &sync.Pool{ + New: func() interface{} { + buffer := make([]byte, 32*1024) + return &buffer + }, +} + +// XAttrErrorHandlers transform a non-nil xattr error. +// Return nil to ignore an error. +// xattrKey can be empty for listxattr operation. +type XAttrErrorHandler func(dst, src, xattrKey string, err error) error + +type copyDirOpts struct { + xeh XAttrErrorHandler +} + +type CopyDirOpt func(*copyDirOpts) error + +// WithXAttrErrorHandler allows specifying XAttrErrorHandler +// If nil XAttrErrorHandler is specified (default), CopyDir stops +// on a non-nil xattr error. +func WithXAttrErrorHandler(xeh XAttrErrorHandler) CopyDirOpt { + return func(o *copyDirOpts) error { + o.xeh = xeh + return nil + } +} + +// WithAllowXAttrErrors allows ignoring xattr errors. +func WithAllowXAttrErrors() CopyDirOpt { + xeh := func(dst, src, xattrKey string, err error) error { + return nil + } + return WithXAttrErrorHandler(xeh) +} + +// CopyDir copies the directory from src to dst. +// Most efficient copy of files is attempted. +func CopyDir(dst, src string, opts ...CopyDirOpt) error { + var o copyDirOpts + for _, opt := range opts { + if err := opt(&o); err != nil { + return err + } + } + inodes := map[uint64]string{} + return copyDirectory(dst, src, inodes, &o) +} + +func copyDirectory(dst, src string, inodes map[uint64]string, o *copyDirOpts) error { + stat, err := os.Stat(src) + if err != nil { + return errors.Wrapf(err, "failed to stat %s", src) + } + if !stat.IsDir() { + return errors.Errorf("source is not directory") + } + + if st, err := os.Stat(dst); err != nil { + if err := os.Mkdir(dst, stat.Mode()); err != nil { + return errors.Wrapf(err, "failed to mkdir %s", dst) + } + } else if !st.IsDir() { + return errors.Errorf("cannot copy to non-directory: %s", dst) + } else { + if err := os.Chmod(dst, stat.Mode()); err != nil { + return errors.Wrapf(err, "failed to chmod on %s", dst) + } + } + + fis, err := ioutil.ReadDir(src) + if err != nil { + return errors.Wrapf(err, "failed to read %s", src) + } + + if err := copyFileInfo(stat, dst); err != nil { + return errors.Wrapf(err, "failed to copy file info for %s", dst) + } + + for _, fi := range fis { + source := filepath.Join(src, fi.Name()) + target := filepath.Join(dst, fi.Name()) + + switch { + case fi.IsDir(): + if err := copyDirectory(target, source, inodes, o); err != nil { + return err + } + continue + case (fi.Mode() & os.ModeType) == 0: + link, err := getLinkSource(target, fi, inodes) + if err != nil { + return errors.Wrap(err, "failed to get hardlink") + } + if link != "" { + if err := os.Link(link, target); err != nil { + return errors.Wrap(err, "failed to create hard link") + } + } else if err := CopyFile(target, source); err != nil { + return errors.Wrap(err, "failed to copy files") + } + case (fi.Mode() & os.ModeSymlink) == os.ModeSymlink: + link, err := os.Readlink(source) + if err != nil { + return errors.Wrapf(err, "failed to read link: %s", source) + } + if err := os.Symlink(link, target); err != nil { + return errors.Wrapf(err, "failed to create symlink: %s", target) + } + case (fi.Mode() & os.ModeDevice) == os.ModeDevice: + if err := copyDevice(target, fi); err != nil { + return errors.Wrapf(err, "failed to create device") + } + default: + // TODO: Support pipes and sockets + return errors.Wrapf(err, "unsupported mode %s", fi.Mode()) + } + if err := copyFileInfo(fi, target); err != nil { + return errors.Wrap(err, "failed to copy file info") + } + + if err := copyXAttrs(target, source, o.xeh); err != nil { + return errors.Wrap(err, "failed to copy xattrs") + } + } + + return nil +} + +// CopyFile copies the source file to the target. +// The most efficient means of copying is used for the platform. +func CopyFile(target, source string) error { + src, err := os.Open(source) + if err != nil { + return errors.Wrapf(err, "failed to open source %s", source) + } + defer src.Close() + tgt, err := os.Create(target) + if err != nil { + return errors.Wrapf(err, "failed to open target %s", target) + } + defer tgt.Close() + + return copyFileContent(tgt, src) +} |