jetsung / copy.go

/* MIT License * * Copyright (c) 2017 Roland Singer [[email protected]] * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in all * copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. */ // CopyFile copies the contents of the file named src to the file named // by dst. The file will be created if it does not already exist. If the // destination file exists, all it's contents will be replaced by the contents // of the source file. The file mode will be copied from the source and // the copied data is synced/flushed to stable storage. func CopyFile(src, dst string) (err error) { in, err := os.Open(src) if err != nil { return } defer in.Close() out, err := os.Create(dst) if err != nil { return } defer func() { if e := out.Close(); e != nil { err = e } }() _, err = io.Copy(out, in) if err != nil { return } err = out.Sync() if err != nil { return } si, err := os.Stat(src) if err != nil { return } err = os.Chmod(dst, si.Mode()) if err != nil { return } return } // CopyDir recursively copies a directory tree, attempting to preserve permissions. // Source directory must exist, destination directory must *not* exist. // Symlinks are ignored and skipped. func CopyDir(src string, dst string) (err error) { src = filepath.Clean(src) dst = filepath.Clean(dst) si, err := os.Stat(src) if err != nil { return err } if !si.IsDir() { return fmt.Errorf("source is not a directory") } _, err = os.Stat(dst) if err != nil && !os.IsNotExist(err) { return } if err == nil { return fmt.Errorf("destination already exists") } err = os.MkdirAll(dst, si.Mode()) if err != nil { return } entries, err := ioutil.ReadDir(src) if err != nil { return } for _, entry := range entries { srcPath := filepath.Join(src, entry.Name()) dstPath := filepath.Join(dst, entry.Name()) if entry.IsDir() { err = CopyDir(srcPath, dstPath) if err != nil { return } } else { // Skip symlinks. if entry.Mode()&os.ModeSymlink != 0 { continue } err = CopyFile(srcPath, dstPath) if err != nil { return } } } return }