gcc/libgo/go/os/dir.go

91 lines
1.8 KiB
Go
Raw Normal View History

// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package os
import (
"io"
"syscall"
"unsafe"
)
//extern opendir
func libc_opendir(*byte) *syscall.DIR
//extern closedir
func libc_closedir(*syscall.DIR) int
// FIXME: pathconf returns long, not int.
//extern pathconf
func libc_pathconf(*byte, int) int
func clen(n []byte) int {
for i := 0; i < len(n); i++ {
if n[i] == 0 {
return i
}
}
return len(n)
}
var elen int
func (file *File) readdirnames(n int) (names []string, err error) {
if elen == 0 {
var dummy syscall.Dirent
elen = (int(unsafe.Offsetof(dummy.Name)) +
libc_pathconf(syscall.StringBytePtr(file.name), syscall.PC_NAME_MAX) +
1)
}
if file.dirinfo == nil {
file.dirinfo = new(dirInfo)
file.dirinfo.buf = make([]byte, elen)
p := syscall.StringBytePtr(file.name)
syscall.Entersyscall()
r := libc_opendir(p)
syscall.Exitsyscall()
file.dirinfo.dir = r
}
entry_dirent := (*syscall.Dirent)(unsafe.Pointer(&file.dirinfo.buf[0]))
size := n
if size <= 0 {
size = 100
n = -1
}
names = make([]string, 0, size) // Empty with room to grow.
dir := file.dirinfo.dir
if dir == nil {
return names, NewSyscallError("opendir", syscall.GetErrno())
}
for n != 0 {
var result *syscall.Dirent
pr := &result
syscall.Entersyscall()
i := libc_readdir_r(dir, entry_dirent, pr)
syscall.Exitsyscall()
if i != 0 {
return names, NewSyscallError("readdir_r", i)
}
if result == nil {
break // EOF
}
var name = string(result.Name[0:clen(result.Name[0:])])
if name == "." || name == ".." { // Useless names
continue
}
names = append(names, name)
n--
}
if n >= 0 && len(names) == 0 {
return names, io.EOF
}
return names, nil
}