Re: Fix a crash in stand-alone Info due to bad indexing of a string

[Eli Zaretskii]

> Date: Wed, 20 Mar 2013 23:28:08 GMT
> From: address@hidden (Karl Berry)
> 
> 1) My first attempts did not reproduce it, though of course I don't
> doubt there is a problem.

What did you try to reproduce?  A crash is specific to the malloc/free
implementation; even for me it happens only on one system to which I
have access, while others simply don't show the up-cased characters.

> 2) Your change has an undesirable side effect for me.  For example:
>   info hello
>   i Exa
> outputs
>   Found `EXAmples' in ...
> instead of the present (and correct)
>   Found `examples' in ...
> 
> (Analogous thing happens with lowercase search strings and uppercase
> index entries.)

This is how the stand-alone Info reader behaved for ages.  That's what
this code fragment is about (note the comment):

    /* If we had a partial match, indicate to the user which part of the
       string matched. */
    match = xstrdup (index_index[i]->label);

    if (partial && show_index_match)
      {
        int k, ls, start, upper;

        ls = strlen (index_search);
        start = partial - ls;
        upper = isupper (match[start]) ? 1 : 0;

        for (k = 0; k < ls; k++)
          if (upper)
            match[k + start] = info_tolower (match[k + start]);
          else
            match[k + start] = info_toupper (match[k + start]);
      }

Try 'info' from Texinfo 4.13, and you will see the same case changes.
The bug in 5.0 inadvertently removed this feature.

> Will take a look when I can, probably you or Sergey will get there first ...

Thanks.