On Sun, Feb 06, 2022 at 08:44:08AM +0800, Weiguo Li wrote:
> To make C header file compatible with C++ linking, a conventional
> practice enclose the code with braces as below:
>
> #ifdef __cplusplus extern "C" { #endif
>
> ...
>
> #ifdef __cplusplus } #endif
>
> Some alternative forms of "#ifdef __cplusplus", like "#if
> defined(__cplusplus)" or "# ifdef __cplusplus", also work.
>
> While it's suspicious when a header file matchs this regular expression
> "if.*__cplusplus" exactly once.
>
> The following script is used to find these files: grep -r ~/git/dpdk
> --include=*.h -e "if.*__cplusplus" -c|grep ":1$"
>
> Apart from two false positive cases, I found some real issues -- some
> missing the left brace parts, the others missing the right brace parts.
>
> In one of the cases, the c++ guard is removed since it's useless in
> private header as previous patch (http://dpdk.org/patch/98948) noted.
> For the other cases, the missing parts are supplemented.
>
Any headers that have filenames not starting with "rte_" are internal
headers, and so should have the guards removed. Therefore, I think that
most patches in this set should just be removing guards. From my tests with
building our public headers in C++ files, resulting in series[1], I only
found one public header with an incorrect guard.
/Bruce
[1]http://patches.dpdk.org/project/dpdk/list/?series=21466
