**
** If the input string is of the form:
**
**      tag:date
**
** Then return the UUID of the oldest check-in with that tag that is
** not older than 'date'.
**
** An input of "tip" returns the most recent check-in.
**
** Memory to hold the returned string comes from malloc() and needs to
** be freed by the caller.
*/
char *tag_to_uuid(const char *zTag){
  char *zUuid = 
    db_text(0,

          "   AND blob.rid=event.objid "
          "   AND event.mtime<=julianday(%Q %s)"
          " ORDER BY event.mtime DESC ",
          zTagBase, zDate, (useUtc ? "" : ",'utc'")
        );
        break;
      }
    }
    if( zUuid==0 && strcmp(zTag, "tip")==0 ){
      zUuid = db_text(0,
        "SELECT blob.uuid"
        "  FROM event, blob"
        " WHERE event.type='ci'"
        "   AND blob.rid=event.objid"
        " ORDER BY event.mtime DESC"
      );
    }
  }
  return zUuid;
}

/*
** Convert a date/time string into a UUID.