Files
sys/unix/dirent.go
dustin-ward 95e765b1cc x/sys/unix: make ReadDirent available on zOS
Currently ReadDirent is not available on zOS. This implementation modifies the current darwin implementation to work on zOS.

Also make tests available on zOS.

Fixes golang/go#54528
Fixes golang/go#54587

Change-Id: I62a09d0068ec8c5fdc849a411ce43bdf14ca3926
Reviewed-on: https://go-review.googlesource.com/c/sys/+/424778
Reviewed-by: Ian Lance Taylor <iant@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Joedian Reid <joedian@golang.org>
Reviewed-by: Bill O'Farrell <billotosyr@gmail.com>
Run-TryBot: Ian Lance Taylor <iant@google.com>
Auto-Submit: Ian Lance Taylor <iant@google.com>
2022-10-13 17:17:32 +00:00

104 lines
3.1 KiB
Go

// 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.
//go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris || zos
// +build aix darwin dragonfly freebsd linux netbsd openbsd solaris zos
package unix
import "unsafe"
// readInt returns the size-bytes unsigned integer in native byte order at offset off.
func readInt(b []byte, off, size uintptr) (u uint64, ok bool) {
if len(b) < int(off+size) {
return 0, false
}
if isBigEndian {
return readIntBE(b[off:], size), true
}
return readIntLE(b[off:], size), true
}
func readIntBE(b []byte, size uintptr) uint64 {
switch size {
case 1:
return uint64(b[0])
case 2:
_ = b[1] // bounds check hint to compiler; see golang.org/issue/14808
return uint64(b[1]) | uint64(b[0])<<8
case 4:
_ = b[3] // bounds check hint to compiler; see golang.org/issue/14808
return uint64(b[3]) | uint64(b[2])<<8 | uint64(b[1])<<16 | uint64(b[0])<<24
case 8:
_ = b[7] // bounds check hint to compiler; see golang.org/issue/14808
return uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 |
uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56
default:
panic("syscall: readInt with unsupported size")
}
}
func readIntLE(b []byte, size uintptr) uint64 {
switch size {
case 1:
return uint64(b[0])
case 2:
_ = b[1] // bounds check hint to compiler; see golang.org/issue/14808
return uint64(b[0]) | uint64(b[1])<<8
case 4:
_ = b[3] // bounds check hint to compiler; see golang.org/issue/14808
return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24
case 8:
_ = b[7] // bounds check hint to compiler; see golang.org/issue/14808
return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 |
uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56
default:
panic("syscall: readInt with unsupported size")
}
}
// ParseDirent parses up to max directory entries in buf,
// appending the names to names. It returns the number of
// bytes consumed from buf, the number of entries added
// to names, and the new names slice.
func ParseDirent(buf []byte, max int, names []string) (consumed int, count int, newnames []string) {
origlen := len(buf)
count = 0
for max != 0 && len(buf) > 0 {
reclen, ok := direntReclen(buf)
if !ok || reclen > uint64(len(buf)) {
return origlen, count, names
}
rec := buf[:reclen]
buf = buf[reclen:]
ino, ok := direntIno(rec)
if !ok {
break
}
if ino == 0 { // File absent in directory.
continue
}
const namoff = uint64(unsafe.Offsetof(Dirent{}.Name))
namlen, ok := direntNamlen(rec)
if !ok || namoff+namlen > uint64(len(rec)) {
break
}
name := rec[namoff : namoff+namlen]
for i, c := range name {
if c == 0 {
name = name[:i]
break
}
}
// Check for useless names before allocating a string.
if string(name) == "." || string(name) == ".." {
continue
}
max--
count++
names = append(names, string(name))
}
return origlen - len(buf), count, names
}