Re: [PATCHES] to_date() validation - Mailing list pgsql-hackers

From Alex Hunsaker
Subject Re: [PATCHES] to_date() validation
Date
Msg-id 34d269d40809091841r34bad6f3sf06ba7a145433ad6@mail.gmail.com
Whole thread Raw
In response to Re: [PATCHES] to_date() validation  ("Brendan Jurd" <direvus@gmail.com>)
List pgsql-hackers
On Tue, Sep 9, 2008 at 6:46 AM, Brendan Jurd <direvus@gmail.com> wrote:
> On Tue, Sep 9, 2008 at 9:04 PM, Brendan Jurd <direvus@gmail.com> wrote:
>> On Tue, Sep 9, 2008 at 7:29 PM, Martijn van Oosterhout
>> <kleptog@svana.org> wrote:
>>> The use of palloc/pfree in this routine seems excessive. Does len have
>>> upper bound? If so a simple array will do it.
>>>
>>

Good catch Martijn!

>> I suppose I could define a constant FORMATNODE_MAX_LEN, make it
>> something like 10 and just use that for copying the string, rather
>> than palloc().  I'll give it a try.
>>
>
> Turns out there was already a relevant constant defined in
> formatting.c: DCH_MAX_ITEM_SIZ, set to 9.  So I just used that, +1 for
> the trailing null.

Cool.

>>>
>>> Here you do not note if we didn't convert the entire string. So it
>>> seems you are allowed to provide too few characters, as long as it's
>>> not the last field?
>>
>> That's true.  The only way to hit that condition would be to provide a
>> semi-bogus value in a string with no separators between the numbers.
>
> I've now plugged this hole.  I added the following error for
> fixed-width inputs that are too short:
>
> postgres=# SELECT to_date('200%1010', 'YYYYMMDD');
> ERROR:  invalid value for "YYYY" in source string
> DETAIL:  Field requires 4 characters, but only 3 could be parsed.
> HINT:  If your source string is not fixed-width, try using the "FM" modifier.

I think thats a big improvement.

> I've attached a new version of the patch (version 3), as well as an
> incremental patch to show the differences between versions 2 and 3.

I looked it over, looks good to me!

> Cheers,
> BJ
>


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