tree 3bebd913d79b7acac599853a2e82c0831421ae77
parent ae0b9da48c91087c5ab78e4918deb69665d0ccc6
author Rich Felker <dalias@aerifal.cx> 1344559637 -0400
committer Rich Felker <dalias@aerifal.cx> 1344559637 -0400

make crypt return an unmatchable hash rather than NULL on failure

unfortunately, a large portion of programs which call crypt are not
prepared for its failure and do not check that the return value is
non-null before using it. thus, always "succeeding" but giving an
unmatchable hash is reportedly a better behavior than failing on
error.

it was suggested that we could do this the same way as other
implementations and put the null-to-unmatchable translation in the
wrapper rather than the individual crypt modules like crypt_des, but
when i tried to do it, i found it was making the logic in __crypt_r
for keeping track of which hash type we're working with and whether it
succeeded or failed much more complex, and potentially error-prone.
the way i'm doing it now seems to have essentially zero cost, anyway.