Ivan Zhakov <ivan_at_visualsvn.com> writes:
>> +/** Callback type for use with svn_repos_verify_fs3(). @a revision
>> + * and @a verify_err are the details of a single verification failure
>> + * that occurred during the svn_repos_verify_fs3() call. @a baton is
>> + * the same baton given to svn_repos_verify_fs3(). @a scratch_pool is
>> + * provided for the convenience of the implementor, who should not
>> + * expect it to live longer than a single callback call.
>> + *
> Who is responsible for clearing verify_err: caller or callback implementor?
That is the caller's responsibility. I documented this in the docstring
that precedes the svn_repos_verify_fs3() declaration ...
+ * failure. Set @c revision callback argument to #SVN_INVALID_REVNUM or
+ * to the revision number respectively. Set @c verify_err to svn_error_t
+ * describing the reason of the failure. @c verify_err will be cleared
+ * after the callback returns, use svn_error_dup() to preserve the error.
...but now I think that it makes sense to say this again in the documentation
for svn_repos_verify_callback_t. So, I committed that in r1687776 .
Anticipating further possible questions, I chose the approach where a calling
site of the callback is responsible for clearing the error because I think
that the reverse design would be rather painful for potential implementors,
including ourselves. The callback can potentially return (other) errors while
processing the verification error, hence transferring the verify_err lifetime
to the callback would require a bigger amount of efforts — just to avoid an
error leak. We also have svn_fs_lock_callback_t that sticks to the same
approach, and I chose not to come up with something new here.
Received on 2015-06-26 16:45:32 CEST