diff options
| author | Sami Kerola <kerolasa@iki.fi> | 2019-03-23 18:16:59 +0000 |
|---|---|---|
| committer | Sami Kerola <kerolasa@iki.fi> | 2019-03-23 18:16:59 +0000 |
| commit | 774f80f4539679a4be785809a8383cc6ccd3148e (patch) | |
| tree | 67b2fc843c3d3474dbb501b2b723ec73d5096256 /iputils_common.h | |
| parent | 9c581b7251a695bfc592443feff9a08a4df8d759 (diff) | |
| download | iputils-774f80f4539679a4be785809a8383cc6ccd3148e.tar.gz | |
common: use single ARRAY_SIZE definition across files
The ARRAY_SIZE is Rusty Russell’s version, that looks a bit more complicated
than the original, but there is a reason to that. This macro will ensure
macro is used properly, and fail compilation if it is not. See reference
link for further explanation.
Reference: http://zubplot.blogspot.com/2015/01/gcc-is-wonderful-better-arraysize-macro.html
Signed-off-by: Sami Kerola <kerolasa@iki.fi>
Diffstat (limited to 'iputils_common.h')
| -rw-r--r-- | iputils_common.h | 8 |
1 files changed, 8 insertions, 0 deletions
diff --git a/iputils_common.h b/iputils_common.h index 61628ac..977365a 100644 --- a/iputils_common.h +++ b/iputils_common.h @@ -1,6 +1,14 @@ #ifndef IPUTILS_COMMON_H #define IPUTILS_COMMON_H +#include <stdio.h> + +#define ARRAY_SIZE(arr) \ + (sizeof(arr) / sizeof((arr)[0]) + \ + sizeof(__typeof__(int[1 - 2 * \ + !!__builtin_types_compatible_p(__typeof__(arr), \ + __typeof__(&arr[0]))])) * 0) + #if defined(USE_IDN) || defined(ENABLE_NLS) # include <locale.h> #endif |