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Diffstat (limited to 'vendor/github.com/containerd/continuity/fs/copy_linux.go')
-rw-r--r--vendor/github.com/containerd/continuity/fs/copy_linux.go144
1 files changed, 144 insertions, 0 deletions
diff --git a/vendor/github.com/containerd/continuity/fs/copy_linux.go b/vendor/github.com/containerd/continuity/fs/copy_linux.go
new file mode 100644
index 000000000..81c71522a
--- /dev/null
+++ b/vendor/github.com/containerd/continuity/fs/copy_linux.go
@@ -0,0 +1,144 @@
+/*
+ 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"
+ "os"
+ "syscall"
+
+ "github.com/containerd/continuity/sysx"
+ "github.com/pkg/errors"
+ "golang.org/x/sys/unix"
+)
+
+func copyFileInfo(fi os.FileInfo, name string) error {
+ st := fi.Sys().(*syscall.Stat_t)
+ if err := os.Lchown(name, int(st.Uid), int(st.Gid)); err != nil {
+ if os.IsPermission(err) {
+ // Normally if uid/gid are the same this would be a no-op, but some
+ // filesystems may still return EPERM... for instance NFS does this.
+ // In such a case, this is not an error.
+ if dstStat, err2 := os.Lstat(name); err2 == nil {
+ st2 := dstStat.Sys().(*syscall.Stat_t)
+ if st.Uid == st2.Uid && st.Gid == st2.Gid {
+ err = nil
+ }
+ }
+ }
+ if err != nil {
+ return errors.Wrapf(err, "failed to chown %s", name)
+ }
+ }
+
+ if (fi.Mode() & os.ModeSymlink) != os.ModeSymlink {
+ if err := os.Chmod(name, fi.Mode()); err != nil {
+ return errors.Wrapf(err, "failed to chmod %s", name)
+ }
+ }
+
+ timespec := []unix.Timespec{unix.Timespec(StatAtime(st)), unix.Timespec(StatMtime(st))}
+ if err := unix.UtimesNanoAt(unix.AT_FDCWD, name, timespec, unix.AT_SYMLINK_NOFOLLOW); err != nil {
+ return errors.Wrapf(err, "failed to utime %s", name)
+ }
+
+ return nil
+}
+
+const maxSSizeT = int64(^uint(0) >> 1)
+
+func copyFileContent(dst, src *os.File) error {
+ st, err := src.Stat()
+ if err != nil {
+ return errors.Wrap(err, "unable to stat source")
+ }
+
+ size := st.Size()
+ first := true
+ srcFd := int(src.Fd())
+ dstFd := int(dst.Fd())
+
+ for size > 0 {
+ // Ensure that we are never trying to copy more than SSIZE_MAX at a
+ // time and at the same time avoids overflows when the file is larger
+ // than 4GB on 32-bit systems.
+ var copySize int
+ if size > maxSSizeT {
+ copySize = int(maxSSizeT)
+ } else {
+ copySize = int(size)
+ }
+ n, err := unix.CopyFileRange(srcFd, nil, dstFd, nil, copySize, 0)
+ if err != nil {
+ if (err != unix.ENOSYS && err != unix.EXDEV) || !first {
+ return errors.Wrap(err, "copy file range failed")
+ }
+
+ buf := bufferPool.Get().(*[]byte)
+ _, err = io.CopyBuffer(dst, src, *buf)
+ bufferPool.Put(buf)
+ return errors.Wrap(err, "userspace copy failed")
+ }
+
+ first = false
+ size -= int64(n)
+ }
+
+ return nil
+}
+
+func copyXAttrs(dst, src string, xeh XAttrErrorHandler) error {
+ xattrKeys, err := sysx.LListxattr(src)
+ if err != nil {
+ e := errors.Wrapf(err, "failed to list xattrs on %s", src)
+ if xeh != nil {
+ e = xeh(dst, src, "", e)
+ }
+ return e
+ }
+ for _, xattr := range xattrKeys {
+ data, err := sysx.LGetxattr(src, xattr)
+ if err != nil {
+ e := errors.Wrapf(err, "failed to get xattr %q on %s", xattr, src)
+ if xeh != nil {
+ if e = xeh(dst, src, xattr, e); e == nil {
+ continue
+ }
+ }
+ return e
+ }
+ if err := sysx.LSetxattr(dst, xattr, data, 0); err != nil {
+ e := errors.Wrapf(err, "failed to set xattr %q on %s", xattr, dst)
+ if xeh != nil {
+ if e = xeh(dst, src, xattr, e); e == nil {
+ continue
+ }
+ }
+ return e
+ }
+ }
+
+ return nil
+}
+
+func copyDevice(dst string, fi os.FileInfo) error {
+ st, ok := fi.Sys().(*syscall.Stat_t)
+ if !ok {
+ return errors.New("unsupported stat type")
+ }
+ return unix.Mknod(dst, uint32(fi.Mode()), int(st.Rdev))
+}