mirror of
https://github.com/vbatts/go-mtree.git
synced 2024-11-25 17:45:39 +00:00
247 lines
8.3 KiB
Go
247 lines
8.3 KiB
Go
package mtree
|
|
|
|
import (
|
|
"crypto/md5"
|
|
"crypto/sha1"
|
|
"crypto/sha256"
|
|
"crypto/sha512"
|
|
"fmt"
|
|
"hash"
|
|
"io"
|
|
"os"
|
|
"strings"
|
|
|
|
"golang.org/x/crypto/ripemd160"
|
|
)
|
|
|
|
// KeywordFunc is the type of a function called on each file to be included in
|
|
// a DirectoryHierarchy, that will produce the string output of the keyword to
|
|
// be included for the file entry. Otherwise, empty string.
|
|
type KeywordFunc func(path string, info os.FileInfo) (string, error)
|
|
|
|
// KeyVal is a "keyword=value"
|
|
type KeyVal string
|
|
|
|
// Keyword is the mapping to the available keywords
|
|
func (kv KeyVal) Keyword() string {
|
|
if !strings.Contains(string(kv), "=") {
|
|
return ""
|
|
}
|
|
chunks := strings.SplitN(strings.TrimSpace(string(kv)), "=", 2)[0]
|
|
if !strings.Contains(chunks, ".") {
|
|
return chunks
|
|
}
|
|
return strings.SplitN(chunks, ".", 2)[0]
|
|
}
|
|
|
|
// KeywordSuffix is really only used for xattr, as the keyword is a prefix to
|
|
// the xattr "namespace.key"
|
|
func (kv KeyVal) KeywordSuffix() string {
|
|
if !strings.Contains(string(kv), "=") {
|
|
return ""
|
|
}
|
|
chunks := strings.SplitN(strings.TrimSpace(string(kv)), "=", 2)[0]
|
|
if !strings.Contains(chunks, ".") {
|
|
return ""
|
|
}
|
|
return strings.SplitN(chunks, ".", 2)[1]
|
|
}
|
|
|
|
// Value is the data/value portion of "keyword=value"
|
|
func (kv KeyVal) Value() string {
|
|
if !strings.Contains(string(kv), "=") {
|
|
return ""
|
|
}
|
|
return strings.SplitN(strings.TrimSpace(string(kv)), "=", 2)[1]
|
|
}
|
|
|
|
// keywordSelector takes an array of "keyword=value" and filters out that only the set of words
|
|
func keywordSelector(keyval, words []string) []string {
|
|
retList := []string{}
|
|
for _, kv := range keyval {
|
|
if inSlice(KeyVal(kv).Keyword(), words) {
|
|
retList = append(retList, kv)
|
|
}
|
|
}
|
|
return retList
|
|
}
|
|
|
|
// NewKeyVals constructs a list of KeyVal from the list of strings, like "keyword=value"
|
|
func NewKeyVals(keyvals []string) KeyVals {
|
|
kvs := make(KeyVals, len(keyvals))
|
|
for i := range keyvals {
|
|
kvs[i] = KeyVal(keyvals[i])
|
|
}
|
|
return kvs
|
|
}
|
|
|
|
// KeyVals is a list of KeyVal
|
|
type KeyVals []KeyVal
|
|
|
|
// Has the "keyword" present in the list of KeyVal, and returns the
|
|
// corresponding KeyVal, else an empty string.
|
|
func (kvs KeyVals) Has(keyword string) KeyVal {
|
|
for i := range kvs {
|
|
if kvs[i].Keyword() == keyword {
|
|
return kvs[i]
|
|
}
|
|
}
|
|
return emptyKV
|
|
}
|
|
|
|
var emptyKV = KeyVal("")
|
|
|
|
// MergeSet takes the current setKeyVals, and then applies the entryKeyVals
|
|
// such that the entry's values win. The union is returned.
|
|
func MergeSet(setKeyVals, entryKeyVals []string) KeyVals {
|
|
retList := NewKeyVals(append([]string{}, setKeyVals...))
|
|
eKVs := NewKeyVals(entryKeyVals)
|
|
seenKeywords := []string{}
|
|
for i := range retList {
|
|
word := retList[i].Keyword()
|
|
if ekv := eKVs.Has(word); ekv != emptyKV {
|
|
retList[i] = ekv
|
|
}
|
|
seenKeywords = append(seenKeywords, word)
|
|
}
|
|
for i := range eKVs {
|
|
if !inSlice(eKVs[i].Keyword(), seenKeywords) {
|
|
retList = append(retList, eKVs[i])
|
|
}
|
|
}
|
|
return retList
|
|
}
|
|
|
|
var (
|
|
// DefaultKeywords has the several default keyword producers (uid, gid,
|
|
// mode, nlink, type, size, mtime)
|
|
DefaultKeywords = []string{
|
|
"size",
|
|
"type",
|
|
"uid",
|
|
"gid",
|
|
"mode",
|
|
"link",
|
|
"nlink",
|
|
"time",
|
|
}
|
|
// SetKeywords is the default set of keywords calculated for a `/set` SpecialType
|
|
SetKeywords = []string{
|
|
"uid",
|
|
"gid",
|
|
}
|
|
// KeywordFuncs is the map of all keywords (and the functions to produce them)
|
|
KeywordFuncs = map[string]KeywordFunc{
|
|
"size": sizeKeywordFunc, // The size, in bytes, of the file
|
|
"type": typeKeywordFunc, // The type of the file
|
|
"time": timeKeywordFunc, // The last modification time of the file
|
|
"link": linkKeywordFunc, // The target of the symbolic link when type=link
|
|
"uid": uidKeywordFunc, // The file owner as a numeric value
|
|
"gid": gidKeywordFunc, // The file group as a numeric value
|
|
"nlink": nlinkKeywordFunc, // The number of hard links the file is expected to have
|
|
"uname": unameKeywordFunc, // The file owner as a symbolic name
|
|
"mode": modeKeywordFunc, // The current file's permissions as a numeric (octal) or symbolic value
|
|
"cksum": cksumKeywordFunc, // The checksum of the file using the default algorithm specified by the cksum(1) utility
|
|
"md5": hasherKeywordFunc("md5", md5.New), // The MD5 message digest of the file
|
|
"md5digest": hasherKeywordFunc("md5digest", md5.New), // A synonym for `md5`
|
|
"rmd160": hasherKeywordFunc("rmd160", ripemd160.New), // The RIPEMD160 message digest of the file
|
|
"rmd160digest": hasherKeywordFunc("rmd160digest", ripemd160.New), // A synonym for `rmd160`
|
|
"ripemd160digest": hasherKeywordFunc("ripemd160digest", ripemd160.New), // A synonym for `rmd160`
|
|
"sha1": hasherKeywordFunc("sha1", sha1.New), // The SHA1 message digest of the file
|
|
"sha1digest": hasherKeywordFunc("sha1digest", sha1.New), // A synonym for `sha1`
|
|
"sha256": hasherKeywordFunc("sha256", sha256.New), // The SHA256 message digest of the file
|
|
"sha256digest": hasherKeywordFunc("sha256digest", sha256.New), // A synonym for `sha256`
|
|
"sha384": hasherKeywordFunc("sha384", sha512.New384), // The SHA384 message digest of the file
|
|
"sha384digest": hasherKeywordFunc("sha384digest", sha512.New384), // A synonym for `sha384`
|
|
"sha512": hasherKeywordFunc("sha512", sha512.New), // The SHA512 message digest of the file
|
|
"sha512digest": hasherKeywordFunc("sha512digest", sha512.New), // A synonym for `sha512`
|
|
|
|
// This is not an upstreamed keyword, but a needed attribute for file validation.
|
|
// The pattern for this keyword key is prefixed by "xattr." followed by the extended attribute "namespace.key".
|
|
// The keyword value is the SHA1 digest of the extended attribute's value.
|
|
// In this way, the order of the keys does not matter, and the contents of the value is not revealed.
|
|
"xattr": xattrKeywordFunc,
|
|
}
|
|
)
|
|
|
|
var (
|
|
modeKeywordFunc = func(path string, info os.FileInfo) (string, error) {
|
|
return fmt.Sprintf("mode=%#o", info.Mode().Perm()), nil
|
|
}
|
|
sizeKeywordFunc = func(path string, info os.FileInfo) (string, error) {
|
|
return fmt.Sprintf("size=%d", info.Size()), nil
|
|
}
|
|
cksumKeywordFunc = func(path string, info os.FileInfo) (string, error) {
|
|
if !info.Mode().IsRegular() {
|
|
return "", nil
|
|
}
|
|
|
|
fh, err := os.Open(path)
|
|
if err != nil {
|
|
return "", err
|
|
}
|
|
defer fh.Close()
|
|
sum, _, err := cksum(fh)
|
|
if err != nil {
|
|
return "", err
|
|
}
|
|
return fmt.Sprintf("cksum=%d", sum), nil
|
|
}
|
|
hasherKeywordFunc = func(name string, newHash func() hash.Hash) KeywordFunc {
|
|
return func(path string, info os.FileInfo) (string, error) {
|
|
if !info.Mode().IsRegular() {
|
|
return "", nil
|
|
}
|
|
|
|
fh, err := os.Open(path)
|
|
if err != nil {
|
|
return "", err
|
|
}
|
|
defer fh.Close()
|
|
|
|
h := newHash()
|
|
if _, err := io.Copy(h, fh); err != nil {
|
|
return "", err
|
|
}
|
|
return fmt.Sprintf("%s=%x", name, h.Sum(nil)), nil
|
|
}
|
|
}
|
|
timeKeywordFunc = func(path string, info os.FileInfo) (string, error) {
|
|
t := info.ModTime().UnixNano()
|
|
return fmt.Sprintf("time=%d.%d", (t / 1e9), (t % (t / 1e9))), nil
|
|
}
|
|
linkKeywordFunc = func(path string, info os.FileInfo) (string, error) {
|
|
if info.Mode()&os.ModeSymlink != 0 {
|
|
str, err := os.Readlink(path)
|
|
if err != nil {
|
|
return "", err
|
|
}
|
|
return fmt.Sprintf("link=%s", str), nil
|
|
}
|
|
return "", nil
|
|
}
|
|
typeKeywordFunc = func(path string, info os.FileInfo) (string, error) {
|
|
if info.Mode().IsDir() {
|
|
return "type=dir", nil
|
|
}
|
|
if info.Mode().IsRegular() {
|
|
return "type=file", nil
|
|
}
|
|
if info.Mode()&os.ModeSocket != 0 {
|
|
return "type=socket", nil
|
|
}
|
|
if info.Mode()&os.ModeSymlink != 0 {
|
|
return "type=link", nil
|
|
}
|
|
if info.Mode()&os.ModeNamedPipe != 0 {
|
|
return "type=fifo", nil
|
|
}
|
|
if info.Mode()&os.ModeDevice != 0 {
|
|
if info.Mode()&os.ModeCharDevice != 0 {
|
|
return "type=char", nil
|
|
}
|
|
return "type=device", nil
|
|
}
|
|
return "", nil
|
|
}
|
|
)
|