Re: [Tarantool-patches] [PATCH v2 2/3] fio: close unused descriptors automatically

[Vladislav Shpilevoy <v.shpilevoy@tarantool.org>]

>> diff --git a/src/lua/fio.lua b/src/lua/fio.lua
>> index 4692e1026..d3c257b88 100644
>> --- a/src/lua/fio.lua
>> +++ b/src/lua/fio.lua
> 
> <snipped>
> 
>> @@ -160,7 +165,22 @@ fio_methods.stat = function(self)
>>      return internal.fstat(self.fh)
>>  end
>>  
>> -local fio_mt = { __index = fio_methods }
>> +fio_methods.__serialize = function(self)
>> +    return {fh = self.fh}
>> +end
>> +
>> +local fio_mt = {
>> +    __index = fio_methods,
>> +    __gc = function(obj)
>> +        if obj.fh >= 0 then
> 
> Considering the current semantics of fio_methods.close (I added the code
> below) if internal.close fails, retry is not triggered in __gc mm due to
> the condition above. I guess you just missed to fix it here (you hoisted
> the error handling in the previous patch).

Yeah, I knew :) I just didn't want to touch this place.
But ok, here is a separate commit to fix this thing, since it
existed before my patch, and is an independent bug.

====================

commit 1dcd0e6ffb1916d38b374f6df634dfcf3c0a40bc
Author: Vladislav Shpilevoy <v.shpilevoy@tarantool.org>
Date:   Fri Mar 20 22:20:20 2020 +0100

    fio: on close() don't loose fd if internal close fails
    
    File descriptor was set to -1 regardless of whether
    the object was closed properly. As a result, in case
    of an error the descriptor would leak.
    
    GC finalizer of a descriptor is left intact not to
    overcomplicate it.

diff --git a/src/lua/fio.lua b/src/lua/fio.lua
index d3c257b88..83fddaa0a 100644
--- a/src/lua/fio.lua
+++ b/src/lua/fio.lua
@@ -146,10 +146,10 @@ end
 
 fio_methods.close = function(self)
     local res, err = internal.close(self.fh)
-    self.fh = -1
     if err ~= nil then
         return false, err
     end
+    self.fh = -1
     return res
 end