Re: [RFC PATCH 2/4] tools/nolibc: add integer types and integer limit macros

From: Willy Tarreau
Date: Sun Feb 19 2023 - 14:23:53 EST


On Sun, Feb 19, 2023 at 07:16:57PM +0000, Thomas Weißschuh wrote:
> On Sun, Feb 19, 2023 at 07:51:31PM +0100, Willy Tarreau wrote:
> > From: Vincent Dagonneau <v@xxxxxx>
> >
> > This commit adds some of the missing integer types to stdint.h and adds
> > limit macros (e.g. INTN_{MIN,MAX}).
> >
> > The reference used for adding these types is
> > https://pubs.opengroup.org/onlinepubs/009695399/basedefs/stdint.h.html.
> >
> > Note that the maximum size of size_t is implementation-defined (>65535),
> > in this case I chose to stick with what the kernel uses in
> > linux/include/uapi/asm-generic/posix_types.h: unsigned int on 32bits and
> > unsigned long on 64bits.
> >
> > Signed-off-by: Vincent Dagonneau <v@xxxxxx>
> > [wt: size_t is always ulong since it matches the word size on all archs
> > we care for; calculate the SIZE_MAX, INTPTR_MIN and INTPTR_MAX based on
> > the compiler-provided __LONG_MAX__]
> > Signed-off-by: Willy Tarreau <w@xxxxxx>
> > ---
> > tools/include/nolibc/stdint.h | 51 +++++++++++++++++++++++++++++++++++
> > 1 file changed, 51 insertions(+)
> >
> > diff --git a/tools/include/nolibc/stdint.h b/tools/include/nolibc/stdint.h
> > index 4ba264031df9..5f1adf9316ca 100644
> > --- a/tools/include/nolibc/stdint.h
> > +++ b/tools/include/nolibc/stdint.h
> > @@ -21,4 +21,55 @@ typedef unsigned long uintptr_t;
> > typedef signed long intptr_t;
> > typedef signed long ptrdiff_t;
> >
> > +typedef int8_t int_least8_t;
> > +typedef uint8_t uint_least8_t;
> > +typedef int16_t int_least16_t;
> > +typedef uint16_t uint_least16_t;
> > +typedef int32_t int_least32_t;
> > +typedef uint32_t uint_least32_t;
> > +typedef int64_t int_least64_t;
> > +typedef uint64_t uint_least64_t;
> > +
> > +typedef int64_t intmax_t;
> > +typedef uint64_t uintmax_t;
> > +
> > +/* limits of integral types */
> > +
> > +#define INT8_MIN (-128)
> > +#define INT16_MIN (-32767-1)
> > +#define INT32_MIN (-2147483647-1)
> > +#define INT64_MIN (-9223372036854775807LL-1)
> > +
> > +#define INT8_MAX (127)
> > +#define INT16_MAX (32767)
> > +#define INT32_MAX (2147483647)
> > +#define INT64_MAX (9223372036854775807LL)
> > +
> > +#define UINT8_MAX (255)
> > +#define UINT16_MAX (65535)
> > +#define UINT32_MAX (4294967295U)
> > +#define UINT64_MAX (18446744073709551615ULL)
> > +
> > +#define INT_LEAST8_MIN INT8_MIN
> > +#define INT_LEAST16_MIN INT16_MIN
> > +#define INT_LEAST32_MIN INT32_MIN
> > +#define INT_LEAST64_MIN INT64_MIN
> > +
> > +#define INT_LEAST8_MAX INT8_MAX
> > +#define INT_LEAST16_MAX INT16_MAX
> > +#define INT_LEAST32_MAX INT32_MAX
> > +#define INT_LEAST64_MAX INT64_MAX
> > +
> > +#define UINT_LEAST8_MAX UINT8_MAX
> > +#define UINT_LEAST16_MAX UINT16_MAX
> > +#define UINT_LEAST32_MAX UINT32_MAX
> > +#define UINT_LEAST64_MAX UINT64_MAX
> > +
> > +#define SIZE_MAX ((__SIZE_TYPE__)(__LONG_MAX__) * 2 + 1)
>
> Nit: size_t would look nicer than __SIZE_TYPE__.

Thanks, I hesitated.

> Also SSIZE_MAX could be added.

Ah I hadn't noticed that ssize_t was defined in the file, in this case
I agree it would be better to have it as well.

> > +#define INTPTR_MIN (-__LONG_MAX__ - 1)
> > +#define INTPTR_MAX __LONG_MAX__
> > +#define UINTPTR_MAX (SIZE_MAX)
>
> Braces seem unnecessary.

Indeed.

Thanks!
Willy