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 @@ +// 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 +} |