Re: [PATCH] newlib: libc: Fix bugs in the commit 3d94e07c49b5.

On Nov 10 20:34, Takashi Yano wrote:
> The commit 3d94e07c49b5 has a few bugs which cause testsuite failure
> in libstdc++. This is due to excess orientation check in __srefill_r()
> and _ungetc_r(). This patch fixes them.

Oops, _ungetc_r is used from ungetwc as well, that's not good. 
Sorry that I missed that yesterday!

> Fixes: 3d94e07c49b5 ("newlib: libc: Fix crash on fprintf to a wide-oriented stream.")
> Reported-by: Christophe Lyon <[email protected]>
> Reviewed-by:
> Signed-off-by: Takashi Yano <[email protected]>
> ---
>  newlib/libc/stdio/refill.c | 3 ---
>  newlib/libc/stdio/ungetc.c | 8 ++------
>  2 files changed, 2 insertions(+), 9 deletions(-)
> 
> diff --git a/newlib/libc/stdio/refill.c b/newlib/libc/stdio/refill.c
> index c1ef7e120..cd71ed152 100644
> --- a/newlib/libc/stdio/refill.c
> +++ b/newlib/libc/stdio/refill.c
> @@ -43,9 +43,6 @@ __srefill_r (struct _reent * ptr,
>  
>    CHECK_INIT (ptr, fp);
>  
> -  if (ORIENT (fp, -1) != -1)
> -    return EOF;
> -
>    fp->_r = 0;			/* largely a convenience for callers */
>  
>    /* SysV does not make this test; take it out for compatibility */
> diff --git a/newlib/libc/stdio/ungetc.c b/newlib/libc/stdio/ungetc.c
> index 79914af08..5053fd6c4 100644
> --- a/newlib/libc/stdio/ungetc.c
> +++ b/newlib/libc/stdio/ungetc.c
> @@ -125,12 +125,6 @@ _ungetc_r (struct _reent *rptr,
>  
>    _newlib_flockfile_start (fp);
>  
> -  if (ORIENT (fp, -1) != -1)
> -    {
> -      _newlib_flockfile_exit (fp);
> -      return EOF;
> -    }
> -
>    /* After ungetc, we won't be at eof anymore */
>    fp->_flags &= ~__SEOF;
>  
> @@ -213,6 +207,8 @@ int
>  ungetc (int c,
>         register FILE *fp)
>  {
> +  if (ORIENT (fp, -1) != -1)
> +    return EOF;
>    return _ungetc_r (_REENT, c, fp);
>  }
>  #endif /* !_REENT_ONLY */
> -- 
> 2.39.0

Didn't you forget ungetwc?

But then again, I checked GLibC, and there's something weird:

ungetc does not at all set or test the orientation.

ungetwc sets the orientation to 1, but doesn't check it.

Puzzeling.  I wonder about the reasoning behind this.


Corinna