Re: [PATCH] Corrections to Documentation/rbtree.txt

[Ian Abbott <abbotti@mev.co.uk>]

On 20/03/08 18:39, Rob Landley wrote:
> On Thursday 20 March 2008 10:29:57 Ian Abbott wrote:
>> From: Ian Abbott <abbotti@mev.co.uk>
>>
>> The description of the rb_entry() macro in Documentation/rbtree.txt seems
>> incorrect. This patch improves it (hopefully).  Also I changed the example
>> code to call the previous 'my_search()' example instead of an undefined
>> 'mysearch()'.
> 
> I have no objection to the patch (and the my_search thing seems like an 
> obvious typo), but is there a reason to prefer rb_entry() rather than 
> container_of()?  If so, the rationale might be a good thing to add to the 
> documentation...

I forgot to mention this in my earlier post, but while we're on the
subject, it might be worth renaming the 'node' variable in the
'my_search()' and iteration examples to avoid confusion in the use of
the rb_entry() (or container_of() macro), for example in 'my_search()',
instead of:

	struct rb_node *node = root->rb_node;

	while (node) {
		struct mytype *data = rb_entry(node, struct mytype, node);

I think this is clearer:

	struct rb_node *pn = root->rb_node;

	while (pn) {
		struct mytype *data = rb_entry(pn, struct mytype, node);

(I used rb_entry instead of container_of in the above.  Also, there are
probably better, longer variable names than 'pn', e.g. 'rbn' or 'rbnode'
or 'pnode'.)

-- 
-=( Ian Abbott @ MEV Ltd.    E-mail: <abbotti@mev.co.uk>        )=-
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