windows: make SID.String() conform to the String interface
This function shouldn't return an error. Like other String() functions
everywhere in Golang, this should instead return empty or a token value
during an error, so that it can be passed to %v and similar. Also, allow
for SID strings of maximum size.
Change-Id: Ib6d8407f8ad0bdabcb22c31b8f387594f2ea7672
Reviewed-on: https://go-review.googlesource.com/c/sys/+/196799
Run-TryBot: Jason A. Donenfeld <Jason@zx2c4.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Alex Brainman <alex.brainman@gmail.com>
diff --git a/windows/security_windows.go b/windows/security_windows.go
index 8e2971d..308d484 100644
--- a/windows/security_windows.go
+++ b/windows/security_windows.go
@@ -227,16 +227,15 @@
}
}
-// String converts SID to a string format
-// suitable for display, storage, or transmission.
-func (sid *SID) String() (string, error) {
+// String converts SID to a string format suitable for display, storage, or transmission.
+func (sid *SID) String() string {
var s *uint16
e := ConvertSidToStringSid(sid, &s)
if e != nil {
- return "", e
+ return ""
}
defer LocalFree((Handle)(unsafe.Pointer(s)))
- return UTF16ToString((*[256]uint16)(unsafe.Pointer(s))[:]), nil
+ return UTF16ToString((*[(1 << 30) - 1]uint16)(unsafe.Pointer(s))[:])
}
// Len returns the length, in bytes, of a valid security identifier SID.
diff --git a/windows/syscall_windows_test.go b/windows/syscall_windows_test.go
index b800409..6130cf2 100644
--- a/windows/syscall_windows_test.go
+++ b/windows/syscall_windows_test.go
@@ -99,12 +99,8 @@
if err != nil {
t.Fatalf("Unable to create well known sid for administrators: %v", err)
}
- sidStr, err := sid.String()
- if err != nil {
- t.Fatalf("Unable to convert sid into string: %v", err)
- }
- if sidStr != "S-1-5-32-544" {
- t.Fatalf("Expecting administrators to be S-1-5-32-544, but found %s instead", sidStr)
+ if got, want := sid.String(), "S-1-5-32-544"; got != want {
+ t.Fatalf("Builtin Administrators SID = %s, want %s", got, want)
}
}
@@ -279,8 +275,7 @@
t.Fatal("Invalid security descriptor owner")
}
if !sdOwner.IsWellKnown(windows.WinBuiltinAdministratorsSid) {
- got, _ := sdOwner.String()
- t.Fatalf("Owner = %q; want S-1-5-32-544", got)
+ t.Fatalf("Owner = %q; want S-1-5-32-544", sdOwner)
}
}
