openssh unix dev - Oct 2017 - [PATCH][RESEND] apply the struct dirent penalty only when needed

Hi,

attached is a patch that reduces the memory in use on all systems where 
BROKEN_ONE_BYTE_DIRENT_D_NAME is not defined.

It would be good if there was a ac_something variable that could be given to 
configure to tell it if this workaround is needed or not when cross compiling. 
We currently do it another way after running configure:

===cat >>conftest.c <<EOF
#include <sys/types.h>
#include <dirent.h>
#include <assert.h>

int
main()
{
        struct dirent d;
        static_assert(sizeof(d.d_name) > sizeof(char), "struct to
small");

        return 0;
}
EOF

${target_platform}-gcc ${optflags} conftest.c && \
        sed -ri 's/#define (BROKEN_ONE_BYTE_DIRENT_D_NAME) 1/#undef \1/'
config.h
===
Of course that only works when one has a compiler that is new enough (what we 
can guarantee).

Greetings,

Eike
-- 
Rolf Eike Beer, emlix GmbH, http://www.emlix.com
Fon +49 551 30664-0, Fax +49 551 30664-11
Bertha-von-Suttner-Str. 9, 37085 G?ttingen, Germany
Sitz der Gesellschaft: G?ttingen, Amtsgericht G?ttingen HR B 3160
Gesch?ftsf?hrung: Heike Jordan, Dr. Uwe Kracke ? Ust-IdNr.: DE 205 198 055

emlix ? smart embedded open source
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On Oct 12 11:57, Rolf Eike Beer wrote:
> Subject: [PATCH 1/3] apply the struct dirent penalty only when needed
> 
> Many systems have a struct dirent that already has enough space to hold the
> entries names, others like Solaris have not. For the latter extra space
needs
> to be allocated, but this was also done for the former systems leading to
> needlessly reserved memory.
> ---
>  sftp-glob.c | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/sftp-glob.c b/sftp-glob.c
> index 43a1beba..8edd28ac 100644
> --- a/sftp-glob.c
> +++ b/sftp-glob.c
> @@ -64,9 +64,14 @@ fudge_opendir(const char *path)
>  static struct dirent *
>  fudge_readdir(struct SFTP_OPENDIR *od)
>  {
> +#ifdef BROKEN_ONE_BYTE_DIRENT_D_NAME
>  	/* Solaris needs sizeof(dirent) + path length (see below) */
>  	static char buf[sizeof(struct dirent) + MAXPATHLEN];
I know this code was already there, but isn't MAXPATHLEN rather wasteful?
Shouldn't that be NAME_LEN + 1 instead?


Corinna

-- 
Corinna Vinschen
Cygwin Maintainer
Red Hat
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