From 834a3f844a77823bf57c323d0927bc1f42b10e61 Mon Sep 17 00:00:00 2001 From: qiulaidongfeng <2645477756@qq.com> Date: Fri, 4 Aug 2023 05:15:41 +0000 Subject: [PATCH] archive/tar: add FileInfoNames interface An optional interface FileInfoNames has been added. If the parameter fi of FileInfoHeader implements the interface the Gname and Uname of the return value Header are provided by the method of the interface. Also added testing. Fixes #50102 Change-Id: I6fd06c7c9aaf29b22b7384542fe57affed33009a Change-Id: I6fd06c7c9aaf29b22b7384542fe57affed33009a GitHub-Last-Rev: 5e82257948759e13880d8af12743b9524ae3df5a GitHub-Pull-Request: golang/go#61662 Reviewed-on: https://go-review.googlesource.com/c/go/+/514235 Run-TryBot: Ian Lance Taylor Reviewed-by: Ian Lance Taylor Reviewed-by: Michael Knyszek TryBot-Result: Gopher Robot Run-TryBot: Ian Lance Taylor Auto-Submit: Ian Lance Taylor --- api/next/50102.txt | 9 +++++++ src/archive/tar/common.go | 32 ++++++++++++++++++++++++ src/archive/tar/stat_unix.go | 10 ++++++++ src/archive/tar/tar_test.go | 48 ++++++++++++++++++++++++++++++++++++ 4 files changed, 99 insertions(+) create mode 100644 api/next/50102.txt diff --git a/api/next/50102.txt b/api/next/50102.txt new file mode 100644 index 0000000000..dcb7977e83 --- /dev/null +++ b/api/next/50102.txt @@ -0,0 +1,9 @@ +pkg archive/tar, type FileInfoNames interface { Gname, IsDir, ModTime, Mode, Name, Size, Sys, Uname } #50102 +pkg archive/tar, type FileInfoNames interface, Gname(int) (string, error) #50102 +pkg archive/tar, type FileInfoNames interface, IsDir() bool #50102 +pkg archive/tar, type FileInfoNames interface, ModTime() time.Time #50102 +pkg archive/tar, type FileInfoNames interface, Mode() fs.FileMode #50102 +pkg archive/tar, type FileInfoNames interface, Name() string #50102 +pkg archive/tar, type FileInfoNames interface, Size() int64 #50102 +pkg archive/tar, type FileInfoNames interface, Sys() interface{} #50102 +pkg archive/tar, type FileInfoNames interface, Uname(int) (string, error) #50102 diff --git a/src/archive/tar/common.go b/src/archive/tar/common.go index d26463501b..f141548db8 100644 --- a/src/archive/tar/common.go +++ b/src/archive/tar/common.go @@ -614,6 +614,8 @@ func (fi headerFileInfo) String() string { // sysStat, if non-nil, populates h from system-dependent fields of fi. var sysStat func(fi fs.FileInfo, h *Header) error +var loadUidAndGid func(fi fs.FileInfo, uid, gid *int) + const ( // Mode constants from the USTAR spec: // See http://pubs.opengroup.org/onlinepubs/9699919799/utilities/pax.html#tag_20_92_13_06 @@ -639,6 +641,10 @@ const ( // Since fs.FileInfo's Name method only returns the base name of // the file it describes, it may be necessary to modify Header.Name // to provide the full path name of the file. +// +// If fi implements [FileInfoNames] +// the Gname and Uname of the header are +// provided by the methods of the interface. func FileInfoHeader(fi fs.FileInfo, link string) (*Header, error) { if fi == nil { return nil, errors.New("archive/tar: FileInfo is nil") @@ -711,12 +717,38 @@ func FileInfoHeader(fi fs.FileInfo, link string) (*Header, error) { } } } + if iface, ok := fi.(FileInfoNames); ok { + var err error + if loadUidAndGid != nil { + loadUidAndGid(fi, &h.Uid, &h.Gid) + } + h.Gname, err = iface.Gname(h.Gid) + if err != nil { + return nil, err + } + h.Uname, err = iface.Uname(h.Gid) + if err != nil { + return nil, err + } + return h, nil + } if sysStat != nil { return h, sysStat(fi, h) } return h, nil } +// FileInfoNames extends [FileInfo] to translate UID/GID to names. +// Passing an instance of this to [FileInfoHeader] permits the caller +// to control UID/GID resolution. +type FileInfoNames interface { + fs.FileInfo + // Uname should translate a UID into a user name. + Uname(uid int) (string, error) + // Gname should translate a GID into a group name. + Gname(gid int) (string, error) +} + // isHeaderOnlyType checks if the given type flag is of the type that has no // data section even if a size is specified. func isHeaderOnlyType(flag byte) bool { diff --git a/src/archive/tar/stat_unix.go b/src/archive/tar/stat_unix.go index 0f3428bc24..5b23d3c830 100644 --- a/src/archive/tar/stat_unix.go +++ b/src/archive/tar/stat_unix.go @@ -17,6 +17,7 @@ import ( func init() { sysStat = statUnix + loadUidAndGid = loadUidAndGidFunc } // userMap and groupMap caches UID and GID lookups for performance reasons. @@ -99,3 +100,12 @@ func statUnix(fi fs.FileInfo, h *Header) error { } return nil } + +func loadUidAndGidFunc(fi fs.FileInfo, uid, gid *int) { + sys, ok := fi.Sys().(*syscall.Stat_t) + if !ok { + return + } + *uid = int(sys.Uid) + *gid = int(sys.Gid) +} diff --git a/src/archive/tar/tar_test.go b/src/archive/tar/tar_test.go index a476f5eb01..6bb27ec3e8 100644 --- a/src/archive/tar/tar_test.go +++ b/src/archive/tar/tar_test.go @@ -848,3 +848,51 @@ func Benchmark(b *testing.B) { }) } + +type fileInfoNames struct{} + +func (f *fileInfoNames) Name() string { + return "tmp" +} + +func (f *fileInfoNames) Size() int64 { + return 0 +} + +func (f *fileInfoNames) Mode() fs.FileMode { + return 0777 +} + +func (f *fileInfoNames) ModTime() time.Time { + return time.Time{} +} + +func (f *fileInfoNames) IsDir() bool { + return false +} + +func (f *fileInfoNames) Sys() any { + return nil +} + +func (f *fileInfoNames) Uname(uid int) (string, error) { + return "Uname", nil +} + +func (f *fileInfoNames) Gname(gid int) (string, error) { + return "Gname", nil +} + +func TestFileInfoHeaderUseFileInfoNames(t *testing.T) { + info := &fileInfoNames{} + header, err := FileInfoHeader(info, "") + if err != nil { + t.Fatal(err) + } + if header.Uname != "Uname" { + t.Fatalf("header.Uname: got %v, want %v", header.Uname, "Uname") + } + if header.Gname != "Gname" { + t.Fatalf("header.Gname: got %v, want %v", header.Gname, "Gname") + } +} -- 2.50.0