[Freeciv-Dev] Re: Split patch (was Re: [RFC PATCH] init_techs)

["Ross W. Wetmore" <rwetmore@xxxxxxxxxxxx>]

At 09:52 AM 01/09/28 +0200, Raimar Falke wrote:
>On Fri, Sep 28, 2001 at 12:00:07AM -0400, Ross W. Wetmore wrote:
>> I like your statement of what you claim to be agreeing to followed
>> by what you actually want to do in practice.
>> 
>> Why on earth would you handle the same buffer contents 3 times with
>> all those allocation and free calls when you could do it once and
>> let the caller deal with at most one extra copy depending on whether
>> the original buffer or the results needed to be preserved.
>> 
>> But most of the time I would expect that no extra copies were required
>> in the caller algorithms.
>
>> split should treat the buffer it was handed as working memory, return
>> pointers into the parsed string elements, and let the caller deal with
>> ALL memory issues.
>
>Ok since there is so much resistance: we implement the strdup/free in
>split if it turns out that every caller of split will copy the string
>because it is needed later. Ok?

A better way is to just implement split to take a buffer and do its
splitting thing in a reasonable and efficient manner.

If everyone needs a strduped version of the original buffer, then do
a wrapper function of the form

int split_that_copies_and_recopies_memory_to_please_raimar(
    const char *const toks, const char *const string, 
    char *items[], int max_items)
{
    int ret;

    char *buffer = strdup(string);
    ret = split(toks, buffer, items, max_items);

    /* do whatever mystrlcopy or items strduping you want to generate
     * memory allocations in items[] that the caller will have to free 
     * but invariably won't, generating hard to track memory leaks.
     *
     * However, most callers will probably want to implement just
     * one of these extra copies, not both and hence will probably
     * find this routine a useless performance inhibitor.
     */

    free(buffer);
    return ret;
}

At least this way, people won't be forced to use your VERY bad programming
practices if they don't want to.

>There just are no memory leaks possible.

You weren't listening again ...

>       Raimar
>-- 
> email: rf13@xxxxxxxxxxxxxxxxx
> "From what I am reading Win98 and NT5.0 will be getting rid of all that
>  crap anyway. Seems that Microsoft has invented something called TCP/IP and
>  another really revolutionary concept called DNS that eliminates the
>  netbios crap too. All that arping from browsers is going to go away.
>  I also hear rumors that they are on the verge of breakthrough discoveries
>  called NFS, and LPD too. Given enough time and money, they might
>  eventually invent Unix."
>    -- George Bonser in linux-kernel

Cheers,
RossW
=====