terraform/config/module/copy_dir.go

125 lines
2.3 KiB
Go
Raw Normal View History

package module
import (
"io"
"os"
"path/filepath"
"strings"
"syscall"
)
// copyDir copies the src directory contents into dst. Both directories
// should already exist.
func copyDir(dst, src string) error {
src, err := filepath.EvalSymlinks(src)
if err != nil {
return err
}
walkFn := func(path string, info os.FileInfo, err error) error {
if err != nil {
return err
}
if path == src {
return nil
}
if strings.HasPrefix(filepath.Base(path), ".") {
// Skip any dot files
if info.IsDir() {
return filepath.SkipDir
} else {
return nil
}
}
// The "path" has the src prefixed to it. We need to join our
// destination with the path without the src on it.
dstPath := filepath.Join(dst, path[len(src):])
// we don't want to try and copy the same file over itself.
if path == dstPath {
return nil
}
// We still might have the same file through a link, so check the
// inode if we can
if eq, err := sameInode(path, dstPath); eq {
return nil
} else if err != nil {
return err
}
// If we have a directory, make that subdirectory, then continue
// the walk.
if info.IsDir() {
if path == filepath.Join(src, dst) {
// dst is in src; don't walk it.
return nil
}
if err := os.MkdirAll(dstPath, 0755); err != nil {
return err
}
return nil
}
// If we have a file, copy the contents.
srcF, err := os.Open(path)
if err != nil {
return err
}
defer srcF.Close()
dstF, err := os.Create(dstPath)
if err != nil {
return err
}
defer dstF.Close()
if _, err := io.Copy(dstF, srcF); err != nil {
return err
}
// Chmod it
return os.Chmod(dstPath, info.Mode())
}
return filepath.Walk(src, walkFn)
}
// sameInode looks up the inode for paths a and b and returns if they are
// equal. On windows this will always return false.
func sameInode(a, b string) (bool, error) {
var aIno, bIno uint64
aStat, err := os.Stat(a)
if err != nil {
if os.IsNotExist(err) {
return false, nil
}
return false, err
}
if st, ok := aStat.Sys().(*syscall.Stat_t); ok {
aIno = st.Ino
}
bStat, err := os.Stat(b)
if err != nil {
if os.IsNotExist(err) {
return false, nil
}
return false, err
}
if st, ok := bStat.Sys().(*syscall.Stat_t); ok {
bIno = st.Ino
}
if aIno > 0 && aIno == bIno {
return true, nil
}
return false, nil
}