Re: [9front] strndup should use strnlen and memcpy

[tlaronde@polynum.com]

On Fri, Dec 18, 2020 at 11:31:22AM +0100, Sigrid Solveig HaflC-nudC3ttir wrote:
> > Open Group does not specify if arg1 should be null terminated or not.
> > https://pubs.opengroup.org/onlinepubs/9699919799/functions/strdup.html
> 
> "Applications should not assume that strndup() will allocate ( size + 1)
> bytes when strlen(s) is smaller than size."
> 
> Pretty sure this means it's supposed to be null-terminated, or
> otherwise it wouldn't mention the "dangerous" strlen right there.

As I read it---but I'm not an english native speaker---this only means
that one shall not infer that the allocation will be len + 1 (since if
the string is shorter, it will be less). This does not say anything
about a terminating '\0' and this is precisely the purpose to copy some
amount of chars in a null terminated array of chars (the dup will be
null terminated; it is not a requirement of the chars array duplicated).
the name could have been mem2nstr (fixed maximum size length str as a 
result, not as an argument).
-- 
        Thierry Laronde <tlaronde +AT+ polynum +dot+ com>
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