[PATCH v5 2/4] tools/nolibc: add integer types and integer limit macros

Vincent Dagonneau
2023-02-20T20:22:08Z

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.

We rely on the compiler-defined __LONG_MAX__ to get the right limits for
ssize_t, size_t, intptr_t, uintptr_t and ptrdiff_t. This compiler
constant seem to have been defined at least since GCC 4.1.2 and clang
3.0.0 on x86_64. It is also defined on ARM (32&64), mips and RISC-V.

Note that the maximum size of size_t is implementation-defined (>65535),
in this case I chose to go with unsigned long on all platforms since
unsigned long == unsigned int on all the platforms we care about. Note
that the kernel uses either unsigned int or unsigned long in
linux/include/uapi/asm-generic/posix_types.h. These should be equivalent
for the plaforms we are targeting.

Also note that the 'fast*' flavor of the types have been chosen to be
always 1 byte for '*fast8*' and always long (a.k.a. size_t/ssize_t) for
the other variants. I have never seen the 'fast*' types in use in the wild
but that seems to be what glibc does.

Signed-off-by: Vincent Dagonneau <v@vda.io>
Signed-off-by: Willy Tarreau <w@1wt.eu>
---
tools/include/nolibc/stdint.h | 77 +++++++++++++++++++++++++++++++++++
1 file changed, 77 insertions(+)

diff --git a/tools/include/nolibc/stdint.h b/tools/include/nolibc/stdint.h
index 4ba264031df9..f7179a583f61 100644
--- a/tools/include/nolibc/stdint.h
+++ b/tools/include/nolibc/stdint.h
@@ -21,4 +21,81 @@ 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 int8_t int_fast8_t;
+typedef uint8_t uint_fast8_t;
+typedef ssize_t int_fast16_t;
+typedef size_t uint_fast16_t;
+typedef ssize_t int_fast32_t;
+typedef size_t uint_fast32_t;
+typedef ssize_t int_fast64_t;
+typedef size_t uint_fast64_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_t)(__LONG_MAX__) * 2 + 1)
+#define SSIZE_MIN (-__LONG_MAX__ - 1)
+#define SSIZE_MAX __LONG_MAX__
+#define INTPTR_MIN SSIZE_MIN
+#define INTPTR_MAX SSIZE_MAX
+#define PTRDIFF_MIN SSIZE_MIN
+#define PTRDIFF_MAX SSIZE_MAX
+#define UINTPTR_MAX SIZE_MAX
+
+#define INT_FAST8_MIN INT8_MIN
+#define INT_FAST16_MIN SSIZE_MIN
+#define INT_FAST32_MIN SSIZE_MIN
+#define INT_FAST64_MIN SSIZE_MIN
+
+#define INT_FAST8_MAX INT8_MAX
+#define INT_FAST16_MAX SSIZE_MAX
+#define INT_FAST32_MAX SSIZE_MAX
+#define INT_FAST64_MAX SSIZE_MAX
+
+#define UINT_FAST8_MAX UINT8_MAX
+#define UINT_FAST16_MAX SIZE_MAX
+#define UINT_FAST32_MAX SIZE_MAX
+#define UINT_FAST64_MAX SIZE_MAX
+
#endif /* _NOLIBC_STDINT_H */
--
2.39.2