Re: [BUGFIX] lexer waits for space to terminate the varname

[Vladimir 'phcoder' Serbinenko]

On Sun, May 3, 2009 at 2:37 PM, Bean <address@hidden> wrote:

Hi,

On Sun, May 3, 2009 at 5:12 PM, Vladimir 'phcoder' Serbinenko

<address@hidden> wrote:
> Hello
>

> On Sat, May 2, 2009 at 4:08 PM, Bean <address@hidden> wrote:
>>
>> Hi,
>>
>> I think there is problem with this patch. Consider ${aa}, the closing
>> character "}" would be left out.
>>
>> Although you can remedy this by swapping:
>>
>>  { GRUB_PARSER_STATE_VARNAME, GRUB_PARSER_STATE_TEXT, ' ', 1},
>>  { GRUB_PARSER_STATE_VARNAME2, GRUB_PARSER_STATE_TEXT, '}', 0},
>
> It's not the same starting state. However similar issue exists with ' ' and
> '\"'

Oh right, I copy the wrong sample.

>>
>> so that '}' would be handled before ' ', but it's still not a good
>> practice, as you have added a logic in code that would depend on the
>> order of state_transitions, which is not apparent for casual code
>> viewer.
>
> Perhaps we should switch to just ordering the transition rules instead of
> separate code for default value
>>
>> Also, ' ' might be used for other transition in the future,
>> this code could break that. I suggest you use {} to enclose the
>> variable that doesn't terminated with space,
>
> It can be a workaround  but the bug is still here. The following pieces of
> code fail:
> 1) echo $hello;
> 2) echo $hello
>

Yeah, and there are other varieties as well, such as -. Perhaps it'd
be simpler to use your fix for now, but you should add some comment in
the source code to indicate its purpose.

What about making it rely on order of rules? It should make it more compact

>> or add the terminating
>> character explicitly in the transition table:
>>
>>
>>  { GRUB_PARSER_STATE_VARNAME, GRUB_PARSER_STATE_TEXT, '/ ', 1},
>>
>>
>> On Sat, May 2, 2009 at 8:02 PM, Vladimir 'phcoder' Serbinenko
>> <address@hidden> wrote:
>> > Hello. A varname may be terminated by any character which isn't in a set
>> > [A-Za-z0-9_] and not only space. Here is a fix
>> >
>> > --
>> > Regards
>> > Vladimir 'phcoder' Serbinenko
>> >
>> > _______________________________________________
>> > Grub-devel mailing list
>> > address@hidden
>> > http://lists.gnu.org/mailman/listinfo/grub-devel
>> >
>> >
>>
>>
>>
>> --
>> Bean
>>
>>
>> _______________________________________________
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>> address@hidden
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>
>
>
> --
> Regards
> Vladimir 'phcoder' Serbinenko
>
> _______________________________________________
> Grub-devel mailing list
> address@hidden
> http://lists.gnu.org/mailman/listinfo/grub-devel
>
>



--
Bean


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-- 
Regards
Vladimir 'phcoder' Serbinenko