On Fri, 31 Jul 2020 15:31:43 +0300 Andy Shevchenko <[email protected]> wrote:
> First of all, there is no compile time check for the SMALL > to be ' ' (0x20, i.e. space). Second, for ZEROPAD the check > is hidden in the code. > > For better maintenance replace BUILD_BUG_ON() with static_assert() > for ZEROPAD and move it closer to the definition. While at it, > introduce check for SMALL. > > Signed-off-by: Andy Shevchenko <[email protected]> > --- > lib/vsprintf.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/lib/vsprintf.c b/lib/vsprintf.c > index 31a674dd2674..8a8ac7ce0289 100644 > --- a/lib/vsprintf.c > +++ b/lib/vsprintf.c > @@ -381,6 +381,9 @@ int num_to_str(char *buf, int size, unsigned long long > num, unsigned int width) > #define SMALL 32 /* use lowercase in hex (must be 32 == > 0x20) */ > #define SPECIAL 64 /* prefix hex with "0x", octal with "0" > */ > > +static_assert(ZEROPAD + ' ' == '0'); I would have it match the comment above: static_assert(ZEROPAD == ('0' - ' ')); But other than that: Reviewed-by: Steven Rostedt (VMware) <[email protected]> -- Steve > +static_assert(SMALL == ' '); > + > enum format_type { > FORMAT_TYPE_NONE, /* Just a string part */ > FORMAT_TYPE_WIDTH, > @@ -507,7 +510,7 @@ char *number(char *buf, char *end, unsigned long long num, > /* zero or space padding */ > if (!(spec.flags & LEFT)) { > char c = ' ' + (spec.flags & ZEROPAD); > - BUILD_BUG_ON(' ' + ZEROPAD != '0'); > + > while (--field_width >= 0) { > if (buf < end) > *buf = c;
