package syscallcompat import ( "bytes" "os" "runtime" "syscall" "testing" "golang.org/x/sys/unix" ) func TestReadlinkat(t *testing.T) { for _, targetLen := range []int{100, 500, 4000} { target := string(bytes.Repeat([]byte("x"), targetLen)) err := syscall.Symlink(target, tmpDir+"/readlinkat") if err != nil { if targetLen > 1000 { // Symlinks longer than 1024 (?) bytes are not supported on // MacOS and XFS t.Logf("skipping targetLen=%d: %v", targetLen, err) continue } t.Fatalf("targetLen=%d: %v", targetLen, err) } target2, err := Readlinkat(tmpDirFd, "readlinkat") if err != nil { t.Fatal(err) } if target != target2 { t.Errorf("target=%q != target2=%q", target, target2) } err = syscall.Unlink(tmpDir + "/readlinkat") if err != nil { t.Fatal(err) } } } func TestOpenat(t *testing.T) { _, err := Openat(tmpDirFd, "testOpenAt", 0, 0) if err == nil { t.Errorf("should have failed") } fd, err := os.Create(tmpDir + "/testOpenAt") if err != nil { t.Fatal(err) } fd.Close() rawFd, err := Openat(tmpDirFd, "testOpenAt", 0, 0) if err != nil { t.Fatal(err) } defer syscall.Close(rawFd) if rawFd < 0 { t.Fatalf("rawFd=%d", rawFd) } // Test with absolute path rawFd, err = Openat(-1, tmpDir+"/testOpenAt", 0, 0) if err != nil { t.Fatal(err) } defer syscall.Close(rawFd) if rawFd < 0 { t.Fatalf("rawFd=%d", rawFd) } } func TestRenameat(t *testing.T) { os.Mkdir(tmpDir+"/dir1", 0700) dir1, err := os.Open(tmpDir + "/dir1") if err != nil { t.Fatal(err) } defer dir1.Close() os.Mkdir(tmpDir+"/dir2", 0700) dir2, err := os.Open(tmpDir + "/dir2") if err != nil { t.Fatal(err) } defer dir2.Close() fd, err := os.Create(tmpDir + "/dir1/f1") if err != nil { t.Fatal(err) } fd.Close() err = Renameat(int(dir1.Fd()), "f1", int(dir2.Fd()), "f2") if err != nil { t.Fatal(err) } _, err = os.Stat(tmpDir + "/dir2/f2") if err != nil { t.Fatal(err) } // Test with absolute path err = Renameat(-1, tmpDir+"/dir2/f2", -1, tmpDir+"/dir2/f1") if err != nil { t.Fatal(err) } _, err = os.Stat(tmpDir + "/dir2/f1") if err != nil { t.Fatal(err) } } func TestUnlinkat(t *testing.T) { os.Mkdir(tmpDir+"/unlink1", 0700) dirfd, err := os.Open(tmpDir + "/unlink1") if err != nil { t.Fatal(err) } defer dirfd.Close() // Try to delete file fd, err := os.Create(tmpDir + "/unlink1/f1") if err != nil { t.Fatal(err) } fd.Close() err = Unlinkat(int(dirfd.Fd()), "f1", 0) if err != nil { t.Fatal(err) } _, err = os.Stat(tmpDir + "/unlink1/f1") if err == nil { t.Fatalf("file not deleted!") } // Try to delete dir err = os.Mkdir(tmpDir+"/unlink1/d1", 0700) if err != nil { t.Fatal(err) } err = Unlinkat(int(dirfd.Fd()), "d1", 0) if err == nil { t.Fatalf("this should fail due to missing AT_REMOVEDIR flag") } err = Unlinkat(int(dirfd.Fd()), "d1", unix.AT_REMOVEDIR) if err != nil { t.Fatal(err) } _, err = os.Stat(tmpDir + "/unlink1/d1") if err == nil { t.Fatalf("dir not deleted!") } // Test with absolute path err = os.Mkdir(tmpDir+"/unlink1/d1", 0700) if err != nil { t.Fatal(err) } err = Unlinkat(-1, tmpDir+"/unlink1/d1", unix.AT_REMOVEDIR) if err != nil { t.Fatal(err) } _, err = os.Stat(tmpDir + "/unlink1/d1") if err == nil { t.Fatalf("dir not deleted!") } } func TestFchmodat(t *testing.T) { regular := "TestFchmodat_Regular" f, err := os.OpenFile(tmpDir+"/"+regular, os.O_CREATE|os.O_WRONLY, 0000) if err != nil { t.Fatal(err) } f.Close() symlink := "TestFchmodat_Symlink" err = syscall.Symlink(regular, tmpDir+"/"+symlink) if err != nil { t.Fatal(err) } dirfd, err := syscall.Open(tmpDir, syscall.O_RDONLY, 0) if err != nil { t.Fatal(err) } defer syscall.Close(dirfd) // Check that chmod on a regular file works ok err = Fchmodat(dirfd, regular, 0111, 0) if err != nil { t.Fatal(err) } var st syscall.Stat_t syscall.Lstat(tmpDir+"/"+regular, &st) st.Mode &= 0777 if st.Mode != 0111 { t.Errorf("wrong mode: %#0o", st.Mode) } err = Fchmodat(dirfd, regular, 0000, 0) if err != nil { t.Error(err) } syscall.Lstat(tmpDir+"/"+regular, &st) st.Mode &= 0777 if st.Mode != 0000 { t.Errorf("wrong mode: %#0o", st.Mode) } // Check what happens on a symlink err = Fchmodat(dirfd, symlink, 0333, 0) if err == nil { syscall.Lstat(tmpDir+"/"+symlink, &st) st.Mode &= 0777 t.Errorf("chmod on symlink should have failed, but did not. New mode=%#0o", st.Mode) } syscall.Lstat(tmpDir+"/"+regular, &st) st.Mode &= 0777 if st.Mode != 0000 { t.Errorf("chmod on symlink affected symlink target: New mode=%#0o", st.Mode) } } // symlinkCheckMode looks if the mode bits in "st" say that this is a symlink. // Calls t.Fatal() if not. func symlinkCheckMode(t *testing.T, st syscall.Stat_t) { if runtime.GOOS == "darwin" { // On MacOS, symlinks don't carry their own permissions, so // only check the file type. if st.Mode&syscall.S_IFMT != syscall.S_IFLNK { t.Fatalf("This is not a symlink: mode = 0%o", st.Mode) } return } if st.Mode != 0120777 { t.Fatalf("Wrong mode, have 0%o, want 0120777", st.Mode) } } func TestSymlinkat(t *testing.T) { err := Symlinkat("/foo/bar/baz", tmpDirFd, "symlink1") if err != nil { t.Fatal(err) } var st syscall.Stat_t err = syscall.Lstat(tmpDir+"/symlink1", &st) if err != nil { t.Fatal(err) } symlinkCheckMode(t, st) // Test with absolute path err = Symlinkat("/foo/bar/baz", -1, tmpDir+"/symlink2") if err != nil { t.Fatal(err) } err = syscall.Lstat(tmpDir+"/symlink2", &st) if err != nil { t.Fatal(err) } symlinkCheckMode(t, st) } func TestMkdirat(t *testing.T) { err := Mkdirat(tmpDirFd, "mkdirat", 0700) if err != nil { t.Fatal(err) } fi, err := os.Stat(tmpDir + "/mkdirat") if err != nil { t.Fatal(err) } if !fi.IsDir() { t.Fatalf("mkdirat did not create a directory") } // Test with absolute path err = Mkdirat(-1, tmpDir+"/mkdirat2", 0700) if err != nil { t.Fatal(err) } fi, err = os.Stat(tmpDir + "/mkdirat2") if err != nil { t.Fatal(err) } if !fi.IsDir() { t.Fatalf("mkdirat did not create a directory") } } func TestFstatat(t *testing.T) { var st unix.Stat_t // stat a normal file (size 3) f, err := os.Create(tmpDir + "/fstatat") if err != nil { t.Fatal(err) } _, err = f.Write([]byte("foo")) if err != nil { t.Fatal(err) } f.Close() err = Fstatat(tmpDirFd, "fstatat", &st, unix.AT_SYMLINK_NOFOLLOW) if err != nil { t.Fatal(err) } if st.Size != 3 { t.Errorf("wrong file size: %d", st.Size) } // stat a symlink and check that the size matches the length of the // symlink target. This proves that we have stat'ed the symlink itself. err = os.Symlink(tmpDir+"/fstatat", tmpDir+"/fstatatSymlink") if err != nil { t.Fatal(err) } err = Fstatat(tmpDirFd, "fstatatSymlink", &st, unix.AT_SYMLINK_NOFOLLOW) if err != nil { t.Fatal(err) } expectedSize := int64(len(tmpDir + "/fstatat")) if st.Size != expectedSize { t.Errorf("symlink size: expected=%d, got=%d", expectedSize, st.Size) } }