Add a single entry to the given mailmap object. If the entry already exists,
it will be replaced with the new entry.
@param mm mailmap to add the entry to
@param real_name the real name to use, or NULL
@param real_email the real email to use, or NULL
@param replace_name the name to replace, or NULL
@param replace_email the email to replace
@return 0 on success, or an error code
Add a single entry to the given mailmap object. If the entry already exists, it will be replaced with the new entry.
@param mm mailmap to add the entry to @param real_name the real name to use, or NULL @param real_email the real email to use, or NULL @param replace_name the name to replace, or NULL @param replace_email the email to replace @return 0 on success, or an error code