You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
102 lines
3.0 KiB
102 lines
3.0 KiB
// 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 |
|
|
|
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 |
|
}
|
|
|