On 02.12.2010 07:57, Blair Zajac wrote:
On 12/1/10 4:38 PM, stef...@apache.org wrote:
Author: stefan2
Date: Thu Dec 2 00:38:17 2010
New Revision: 1041230
URL: http://svn.apache.org/viewvc?rev=1041230&view=rev
Log:
Fix the svn_checksum_to_cstring() docstring to actually say what
was intended. Also, make clear that the behavior is new for 1.7 and
trying to use it in 1.6 will cause segfaults.
* subversion/include/svn_checksum.h
(svn_checksum_to_cstring): fix docstring
What happens if somebody makes a svn tool that is compiled and built
against the new 1.7 behavior and then it is backported to 1.6, it may
core dump.
Should we add a svn_checksum_to_cstring2() instead with the new
behavior or backport this change to 1.6? But even then we'll have 1.6
versions with different behavior. It seems making a new
svn_checksum_to_cstring2() is better.
I've felt kind of uneasy about that issue as well.
However, it would have been difficult to implement
a deprecated svn_checksum_to_cstring() in terms
of svn_checksum_to_cstring2(). For instance:
const char *
svn_checksum_to_cstring(const svn_checksum_t *checksum,
apr_pool_t *pool)
{
if (checksum == NULL)
abort();
return svn_checksum_to_cstring2(checksum, pool);
}
does not have the exact same behavior as the old
implementation. Even if we added error output etc.,
that very message may be ignored by / masked in
the calling process. Forcing a segfault via
if (checksum == NULL)
return (const char*)checksum->digest;
might not be liked by some compilers / optimizers
because they know checksum to be NULL in the
return statement.
-- Stefan^2.
