Re: [patch] CodingStyle: add some more error handling guidelines

Julia Lawall
2014-12-02T09:09:02Z

> @@ -403,9 +408,10 @@ The rationale is:
> int fun(int a)
> {
> int result = 0;
> - char *buffer = kmalloc(SIZE);
> + char *buffer;
>
> - if (buffer = NULL)
> + buffer = kmalloc(SIZE);

kmalloc actually takes two arguments. Perhaps it would be better to show
something that looks like a valid call.

Otherwise,

Acked-by: Julia Lawall <julia.lawall@lip6.fr>

julia

> + if (!buffer)
> return -ENOMEM;
>
> if (condition1) {
> @@ -413,14 +419,25 @@ int fun(int a)
> ...
> }
> result = 1;
> - goto out;
> + goto out_buffer;
> }
> ...
> -out:
> +out_buffer:
> kfree(buffer);
> return result;
> }
>
> +A common type of bug to be aware of it "one err bugs" which look like this:
> +
> +err:
> + kfree(foo->bar);
> + kfree(foo);
> + return ret;
> +
> +The bug in this code is that on some exit paths "foo" is NULL. Normally the
> +fix for this is to split it up into two error labels "err_bar:" and "err_foo:".
> +
> +
> Chapter 8: Commenting
>
> Comments are good, but there is also a danger of over-commenting. NEVER
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