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Re: printf: %ls or %S does not work when string is of length 1.


Corinna Vinschen wrote:
On Aug 27 14:31, Jeff Johnston wrote:
Corinna Vinschen wrote:
I tracked this down to a problem in the function _wcsrtombs_r.

The condition to write a converted character into the destination string
and to continue the loop is (wcsrtombs.c, line 48):

if (n <= len - bytes && bytes < len)

The second half of this condition is wrong, AFAICS.  First of all, it
should be bytes <= len instead of bytes < len.  Second, this part of the
condition is already catched by the first part of the condition:

n <= len - bytes <==> n + bytes <= len

with n always >= 0, bytes is always <= len if n + bytes is <= len.  So
the condition is redundant.

Thanks for looking at this Corinna.

Actually, the second part is needed because the first equation is unsigned. Let's say len is 1 but bytes is 2. len - bytes is (unsigned)-1. We don't want to write at this point. Thus, we make the additional check that bytes is actually <= len. I just modified your change and checked it in.

Thank you. But... wouldn't


if (n + bytes <= len)

have the same result?

Well sure, if one wants to be practical :) Patch checked in.

-- Jeff J.



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