dip/vendor/github.com/karrick/godirwalk/readdir_unix.go

132 lines
3.5 KiB
Go

// +build !windows
package godirwalk
import (
"os"
"syscall"
"unsafe"
)
// MinimumScratchBufferSize specifies the minimum size of the scratch buffer
// that ReadDirents, ReadDirnames, Scanner, and Walk will use when reading file
// entries from the operating system. During program startup it is initialized
// to the result from calling `os.Getpagesize()` for non Windows environments,
// and 0 for Windows.
var MinimumScratchBufferSize = os.Getpagesize()
func newScratchBuffer() []byte { return make([]byte, MinimumScratchBufferSize) }
func readDirents(osDirname string, scratchBuffer []byte) ([]*Dirent, error) {
var entries []*Dirent
var workBuffer []byte
dh, err := os.Open(osDirname)
if err != nil {
return nil, err
}
fd := int(dh.Fd())
if len(scratchBuffer) < MinimumScratchBufferSize {
scratchBuffer = newScratchBuffer()
}
var sde syscall.Dirent
for {
if len(workBuffer) == 0 {
n, err := syscall.ReadDirent(fd, scratchBuffer)
// n, err := unix.ReadDirent(fd, scratchBuffer)
if err != nil {
if err == syscall.EINTR /* || err == unix.EINTR */ {
continue
}
_ = dh.Close()
return nil, err
}
if n <= 0 { // end of directory: normal exit
if err = dh.Close(); err != nil {
return nil, err
}
return entries, nil
}
workBuffer = scratchBuffer[:n] // trim work buffer to number of bytes read
}
copy((*[unsafe.Sizeof(syscall.Dirent{})]byte)(unsafe.Pointer(&sde))[:], workBuffer)
workBuffer = workBuffer[reclen(&sde):] // advance buffer for next iteration through loop
if inoFromDirent(&sde) == 0 {
continue // inode set to 0 indicates an entry that was marked as deleted
}
nameSlice := nameFromDirent(&sde)
nameLength := len(nameSlice)
if nameLength == 0 || (nameSlice[0] == '.' && (nameLength == 1 || (nameLength == 2 && nameSlice[1] == '.'))) {
continue
}
childName := string(nameSlice)
mt, err := modeTypeFromDirent(&sde, osDirname, childName)
if err != nil {
_ = dh.Close()
return nil, err
}
entries = append(entries, &Dirent{name: childName, path: osDirname, modeType: mt})
}
}
func readDirnames(osDirname string, scratchBuffer []byte) ([]string, error) {
var entries []string
var workBuffer []byte
var sde *syscall.Dirent
dh, err := os.Open(osDirname)
if err != nil {
return nil, err
}
fd := int(dh.Fd())
if len(scratchBuffer) < MinimumScratchBufferSize {
scratchBuffer = newScratchBuffer()
}
for {
if len(workBuffer) == 0 {
n, err := syscall.ReadDirent(fd, scratchBuffer)
// n, err := unix.ReadDirent(fd, scratchBuffer)
if err != nil {
if err == syscall.EINTR /* || err == unix.EINTR */ {
continue
}
_ = dh.Close()
return nil, err
}
if n <= 0 { // end of directory: normal exit
if err = dh.Close(); err != nil {
return nil, err
}
return entries, nil
}
workBuffer = scratchBuffer[:n] // trim work buffer to number of bytes read
}
sde = (*syscall.Dirent)(unsafe.Pointer(&workBuffer[0])) // point entry to first syscall.Dirent in buffer
// Handle first entry in the work buffer.
workBuffer = workBuffer[reclen(sde):] // advance buffer for next iteration through loop
if inoFromDirent(sde) == 0 {
continue // inode set to 0 indicates an entry that was marked as deleted
}
nameSlice := nameFromDirent(sde)
nameLength := len(nameSlice)
if nameLength == 0 || (nameSlice[0] == '.' && (nameLength == 1 || (nameLength == 2 && nameSlice[1] == '.'))) {
continue
}
entries = append(entries, string(nameSlice))
}
}