Removing function names from errors (PR 9058)

[Roumen Petrov]

Hi Viktor,

Viktor Dukhovni wrote:
> On Wed, Jun 12, 2019 at 10:02:25AM +0100, Matt Caswell wrote:
>
>> OTOH I do find them quite helpful from a debugging perspective, e.g. when people
>> send in questions along the lines of "I got this error what does it mean/how do
>> I fix it" - although what is actually useful is usually the function name rather
>> than the function code itself.
> Indeed what's needed is the function name.  The numeric code is far
> less important.  On the error consumer side, the idiom I'm familiar
> with is:
>
>      while ((err = ERR_get_error_line_data(&file, &line, &data, &flags)) != 0) {
>          ERR_error_string_n(err, buffer, sizeof(buffer));
>          if (flags & ERR_TXT_STRING)
>              printf("...: %s:%s:%d:%s", buffer, file, line, data);
>          else
>              printf("...: %s:%s:%d", buffer, file, line);
>      }
>
> this makes no explicit reference to function numbers, returning the
> appropriate strings.  So any change is likely limited to error
> producers.
Actually err encodes library, function and reason.

>
> On the producer side, my ssl_dane library (used in Exim for example),
> does depend on the function ordinal API:
>
>      https://github.com/vdukhovni/ssl_dane/blob/master/danessl.c#L52-L118
>      https://github.com/vdukhovni/ssl_dane/blob/master/danessl.c#L52-L118
Why you tables with functions and reasons does not use ERR_PACK ?


> so that would need to change (or be longer supported) if the function
> ordinals are replaced by strings, or otherwise change.
>