diff options
Diffstat (limited to 'vendor/golang.org/x/sys/unix/dirent.go')
| -rw-r--r-- | vendor/golang.org/x/sys/unix/dirent.go | 102 |
1 files changed, 102 insertions, 0 deletions
diff --git a/vendor/golang.org/x/sys/unix/dirent.go b/vendor/golang.org/x/sys/unix/dirent.go new file mode 100644 index 0000000..1ebf117 --- /dev/null +++ b/vendor/golang.org/x/sys/unix/dirent.go | |||
| @@ -0,0 +1,102 @@ | |||
| 1 | // Copyright 2009 The Go Authors. All rights reserved. | ||
| 2 | // Use of this source code is governed by a BSD-style | ||
| 3 | // license that can be found in the LICENSE file. | ||
| 4 | |||
| 5 | //go:build aix || darwin || dragonfly || freebsd || linux || netbsd || openbsd || solaris || zos | ||
| 6 | |||
| 7 | package unix | ||
| 8 | |||
| 9 | import "unsafe" | ||
| 10 | |||
| 11 | // readInt returns the size-bytes unsigned integer in native byte order at offset off. | ||
| 12 | func readInt(b []byte, off, size uintptr) (u uint64, ok bool) { | ||
| 13 | if len(b) < int(off+size) { | ||
| 14 | return 0, false | ||
| 15 | } | ||
| 16 | if isBigEndian { | ||
| 17 | return readIntBE(b[off:], size), true | ||
| 18 | } | ||
| 19 | return readIntLE(b[off:], size), true | ||
| 20 | } | ||
| 21 | |||
| 22 | func readIntBE(b []byte, size uintptr) uint64 { | ||
| 23 | switch size { | ||
| 24 | case 1: | ||
| 25 | return uint64(b[0]) | ||
| 26 | case 2: | ||
| 27 | _ = b[1] // bounds check hint to compiler; see golang.org/issue/14808 | ||
| 28 | return uint64(b[1]) | uint64(b[0])<<8 | ||
| 29 | case 4: | ||
| 30 | _ = b[3] // bounds check hint to compiler; see golang.org/issue/14808 | ||
| 31 | return uint64(b[3]) | uint64(b[2])<<8 | uint64(b[1])<<16 | uint64(b[0])<<24 | ||
| 32 | case 8: | ||
| 33 | _ = b[7] // bounds check hint to compiler; see golang.org/issue/14808 | ||
| 34 | return uint64(b[7]) | uint64(b[6])<<8 | uint64(b[5])<<16 | uint64(b[4])<<24 | | ||
| 35 | uint64(b[3])<<32 | uint64(b[2])<<40 | uint64(b[1])<<48 | uint64(b[0])<<56 | ||
| 36 | default: | ||
| 37 | panic("syscall: readInt with unsupported size") | ||
| 38 | } | ||
| 39 | } | ||
| 40 | |||
| 41 | func readIntLE(b []byte, size uintptr) uint64 { | ||
| 42 | switch size { | ||
| 43 | case 1: | ||
| 44 | return uint64(b[0]) | ||
| 45 | case 2: | ||
| 46 | _ = b[1] // bounds check hint to compiler; see golang.org/issue/14808 | ||
| 47 | return uint64(b[0]) | uint64(b[1])<<8 | ||
| 48 | case 4: | ||
| 49 | _ = b[3] // bounds check hint to compiler; see golang.org/issue/14808 | ||
| 50 | return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 | ||
| 51 | case 8: | ||
| 52 | _ = b[7] // bounds check hint to compiler; see golang.org/issue/14808 | ||
| 53 | return uint64(b[0]) | uint64(b[1])<<8 | uint64(b[2])<<16 | uint64(b[3])<<24 | | ||
| 54 | uint64(b[4])<<32 | uint64(b[5])<<40 | uint64(b[6])<<48 | uint64(b[7])<<56 | ||
| 55 | default: | ||
| 56 | panic("syscall: readInt with unsupported size") | ||
| 57 | } | ||
| 58 | } | ||
| 59 | |||
| 60 | // ParseDirent parses up to max directory entries in buf, | ||
| 61 | // appending the names to names. It returns the number of | ||
| 62 | // bytes consumed from buf, the number of entries added | ||
| 63 | // to names, and the new names slice. | ||
| 64 | func ParseDirent(buf []byte, max int, names []string) (consumed int, count int, newnames []string) { | ||
| 65 | origlen := len(buf) | ||
| 66 | count = 0 | ||
| 67 | for max != 0 && len(buf) > 0 { | ||
| 68 | reclen, ok := direntReclen(buf) | ||
| 69 | if !ok || reclen > uint64(len(buf)) { | ||
| 70 | return origlen, count, names | ||
| 71 | } | ||
| 72 | rec := buf[:reclen] | ||
| 73 | buf = buf[reclen:] | ||
| 74 | ino, ok := direntIno(rec) | ||
| 75 | if !ok { | ||
| 76 | break | ||
| 77 | } | ||
| 78 | if ino == 0 { // File absent in directory. | ||
| 79 | continue | ||
| 80 | } | ||
| 81 | const namoff = uint64(unsafe.Offsetof(Dirent{}.Name)) | ||
| 82 | namlen, ok := direntNamlen(rec) | ||
| 83 | if !ok || namoff+namlen > uint64(len(rec)) { | ||
| 84 | break | ||
| 85 | } | ||
| 86 | name := rec[namoff : namoff+namlen] | ||
| 87 | for i, c := range name { | ||
| 88 | if c == 0 { | ||
| 89 | name = name[:i] | ||
| 90 | break | ||
| 91 | } | ||
| 92 | } | ||
| 93 | // Check for useless names before allocating a string. | ||
| 94 | if string(name) == "." || string(name) == ".." { | ||
| 95 | continue | ||
| 96 | } | ||
| 97 | max-- | ||
| 98 | count++ | ||
| 99 | names = append(names, string(name)) | ||
| 100 | } | ||
| 101 | return origlen - len(buf), count, names | ||
| 102 | } | ||
