Re: [patch] Avoid some of the sc_ rules to freeze

[Pádraig Brady]

On 21/02/10 13:43, address@hidden wrote:
> Hi.
>
> Just another little patch to avoid some of the sc_* rules to freeze if
> the filtering of VC_LIST_EXCEPT gives an empty string (for example,
> 'make sc_error_exit_success' freezes if there are not source files in
> ${srcdir}/).
>
> I found this problem due to the bazaar issue in vc-list-files.
>
>
> 2010-02-21  Jose E. Marchesi<address@hidden>
>
>         * top/maint.mk (sc_error_exit_success): Apply the rule only if the
>         filtering of VC_LIST_EXCEPT is not empty.  Otherwise the main grep
>         freezes waiting for data in the standard input.
>         (sc_makefile_TAB_only_indentation): Likewise.
>         (sc_makefile_path_separator_check): Likewise.
>         (sc_m4_quote_check): Likewise.
>
> diff --git a/top/maint.mk b/top/maint.mk
> index 7d84b6c..11afe6b 100644
> --- a/top/maint.mk
> +++ b/top/maint.mk
> @@ -217,9 +217,13 @@ sc_prohibit_magic_number_exit:
>   # Using EXIT_SUCCESS as the first argument to error is misleading,
>   # since when that parameter is 0, error does not exit.  Use `0' instead.
>   sc_error_exit_success:
> -       @grep -nE 'error \(EXIT_SUCCESS,'                               \
> -           $$($(VC_LIST_EXCEPT) | grep -E '\.[chly]$$')&&              \
> -         { echo '$(ME): found error (EXIT_SUCCESS' 1>&2; exit 1; } || :
> +       @if $(VC_LIST_EXCEPT) | grep -E '\.[chly]$$'>  /dev/null; then  \
> +         grep -nE 'error \(EXIT_SUCCESS,'                              \
> +               $$($(VC_LIST_EXCEPT) | grep -E '\.[chly]$$')&&          \
> +         { echo '$(ME): found error (EXIT_SUCCESS'                     \
> +               1>&2; exit 1; } || :;                                    \
> +       else :;                                                         \
> +       fi

Would it be better to just add /dev/null as a parameter to grep?
I.E. like:

        @grep -nE 'error \(EXIT_SUCCESS,'                               \
            $$($(VC_LIST_EXCEPT) /dev/null | grep -E '\.[chly]$$')&&    \
          { echo '$(ME): found error (EXIT_SUCCESS' 1>&2; exit 1; } || :

cheers,
Pádraig.