Re: [PATCH] vsprintf: replace space with readable '=' before crng is ready

From: Tobin C. Harding
Date: Tue Feb 13 2018 - 14:46:28 EST


On Tue, Feb 13, 2018 at 08:16:57AM +0100, Rasmus Villemoes wrote:
> On 13 February 2018 at 07:20, Shunyong Yang
> <shunyong.yang@xxxxxxxxxxxxxxxx> wrote:
>
> >
> > This patch replaces space with readable "=" when output needs padding.
> > Following is the output after applying the patch,
>
> > Suggested-by: Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx>
> >
> > if (unlikely(!have_filled_random_ptr_key)) {
> > + char *ptrval_str = "(ptrval)";
> > + char str[default_width + 1];
> > + int len = strlen(ptrval_str);
> > +
> > + if (default_width > len) {
> > + int pos;
> > +
> > + pos = (default_width - len) / 2;
> > + memset(str, '=', default_width);
> > + memcpy(str + pos + 1, ptrval_str + 1, len - 2);
> > + str[0] = '(';
> > + str[default_width - 1] = ')';
> > + str[default_width] = 0;
> > + ptrval_str = str;
> > + }
> > +
>
> I'm sorry, but that's way too convoluted.
>
> > spec.field_width = default_width;
> > /* string length must be less than default_width */
> > - return string(buf, end, "(ptrval)", spec);
> > + return string(buf, end, ptrval_str, spec);
> > }
>
> I was thinking of just doing something like
>
> - return string(buf, end, "(ptrval)", spec);
> + return string(buf, end, sizeof(void *) == 8 ?
> "(====ptrval====)" : "(ptrval)", spec);

Awesome.