lkml.org 
[lkml]   [2008]   [Mar]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [Pull] Some documentation patches
Jan Engelhardt пишет:
>
> On Friday 2008-03-28 19:20, Jonathan Corbet wrote:
>> commit 9756ccfda31b4c4544aa010aacf71b6672d668e8
>> Date: Fri Mar 28 11:19:56 2008 -0600
>>
>> Add the seq_file documentation
>
> patch on top:
>
> - add const qualifiers
> - remove void* casts
> - use proper specifier (%Ld is not valid)
>
> Signed-off-by: Jan Engelhardt <jengelh@computergmbh.de>
>
> diff --git a/Documentation/filesystems/seq_file.txt
> b/Documentation/filesystems/seq_file.txt
> index 92975ee..cc6cdb9 100644
> --- a/Documentation/filesystems/seq_file.txt
> +++ b/Documentation/filesystems/seq_file.txt
> @@ -107,8 +107,8 @@ complete. Here's the example version:
>
> static void *ct_seq_next(struct seq_file *s, void *v, loff_t *pos)
> {
> - loff_t *spos = (loff_t *) v;
> - *pos = ++(*spos);
> + loff_t *spos = v;
> + *pos = ++*spos;

Excuse me, what's the point in this change and the next one? IMO, removing
the explicit type cast makes the code less obvious (AFAICT, this is a trendy
word in LKML these days). Relying upon operator priorities instead of explicit
operator grouping using parentheses can confuse people, too. Imagine a
person looking at these lines: after the change, he or she will need to check
the variable v type in the argument list, and consult the table of operator
priorities in C if the person is in doubt about what the code does.

Just my two cents...

Dmitri

> return spos;
> }
>
> @@ -127,8 +127,8 @@ something goes wrong. The example module's show()
> function is:
>
> static int ct_seq_show(struct seq_file *s, void *v)
> {
> - loff_t *spos = (loff_t *) v;
> - seq_printf(s, "%Ld\n", *spos);
> + loff_t *spos = v;
> + seq_printf(s, "%lld\n", (long long)*spos);
> return 0;
> }
>
> @@ -136,7 +136,7 @@ We will look at seq_printf() in a moment. But first,
> the definition of the
> seq_file iterator is finished by creating a seq_operations structure with
> the four functions we have just defined:
>
> - static struct seq_operations ct_seq_ops = {
> + static const struct seq_operations ct_seq_ops = {
> .start = ct_seq_start,
> .next = ct_seq_next,
> .stop = ct_seq_stop,
> @@ -204,7 +204,7 @@ line, as in the example module:
> static int ct_open(struct inode *inode, struct file *file)
> {
> return seq_open(file, &ct_seq_ops);
> - };
> + }
>
> Here, the call to seq_open() takes the seq_operations structure we created
> before, and gets set up to iterate through the virtual file.
> @@ -219,7 +219,7 @@ The other operations of interest - read(), llseek(),
> and release() - are
> all implemented by the seq_file code itself. So a virtual file's
> file_operations structure will look like:
>
> - static struct file_operations ct_file_ops = {
> + static const struct file_operations ct_file_ops = {
> .owner = THIS_MODULE,
> .open = ct_open,
> .read = seq_read,
> --
> To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
> the body of a message to majordomo@vger.kernel.org
> More majordomo info at http://vger.kernel.org/majordomo-info.html
> Please read the FAQ at http://www.tux.org/lkml/
>

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2008-03-31 16:35    [from the cache]
©2003-2011 Jasper Spaans