[Libguestfs] [PATCH nbdkit v2 4/4] server: debug: Escape debug strings

[Richard W.M. Jones]

On Tue, May 09, 2023 at 03:05:41PM +0200, Laszlo Ersek wrote:
[...]
> Then, in the post-patch version, the following catches my eye:
> 
>   fp_inner = open_memstream (&str_inner, &len_inner);
>   if (fp_inner == NULL) {
>   fail:
>     /* Try to emit what we can. */
>     errno = err;
>     vfprintf (stderr, fs, args);
>     fprintf (stderr, "\n");
>     return;
>   }
>   errno = err;
>   vfprintf (fp_inner, fs, args);
> 
> Here a common "errno = err" assignment can be factored out, placed just
> after the "fp_inner" assignment. But this isn't really relevant, as
> fixing problem (2) -- i.e., moving "fail" at the end of the function --
> might reorder the code such that this code extraction is no longer
> needed or possible.

I'd prefer to keep the duplicated errno assignment.  It needs to be
right before the call to vfprintf so that %m expands correctly in the
format string.

Agreed on the other points.

Rich.

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