DB.Close(): funlock error

[kwf2030]

windows 10 x64
golang 1.9.1 and 1.8.4
bbolt v1.3.1-coreos.2(no problem with v1.3.1-coreos.1)

error when calling bolt.DB.Close()：
2017/10/10 11:05:57 bolt.Close(): funlock error: The segment is already unlocked.

#35(Support no timeout locks on db files) lead to this issue

[rgeronimi]

It looks like this patch (my mistake) locked the wrong file descriptor.

Before the patch the file descriptor used was based on db.lockfile:
err := lockFileEx(syscall.Handle(db.lockfile.Fd()), flag, 0, 1, 0, &syscall.Overlapped{})

The patch factored it out of the loop, but based on db.file:
fd := db.file.Fd() ... err := lockFileEx(syscall.Handle(fd), flag, 0, 1, 0, &syscall.Overlapped{})

The file vs. lockfile subtlety seems to exist only on Windows, as the db struct definition tells.

I could happily patch it but I don't have anymore (and won't have for the coming months) a Windows platform to test it. But if you have one, let me know and we can do it together.

[kwf2030]

I just modified bolt_windows.go at line 65, change fd := db.file.Fd() to fd := f.Fd() and it seems fixed @rgeronimi

[rgeronimi]

LGTM

[xiang90]

can you send a patch to fix this?

[kwf2030]

@rgeronimi @xiang90 I have just create a pr #64

[xiang90]

fixed by #64

[rgeronimi]

Thks