Adopting next development step of libisofs

libisoburn/data_source.c

@@ -147,6 +147,10 @@ int ds_read_block(IsoDataSource *src, uint32_t lba, uint8_t *buffer)
      return 1;
    tiles[oldest].last_error_lba = lba;
 
+#ifdef ISO_DATA_SOURCE_MISHAP
+   ret= ISO_DATA_SOURCE_MISHAP;
+#else
+   /* <<< pre libisofs-0.6.7 */
    /* It is not required by the specs of libisofs but implicitely assumed
       ...
       But it is not possible to ignore FAILURE.
@@ -159,6 +163,8 @@ int ds_read_block(IsoDataSource *src, uint32_t lba, uint8_t *buffer)
       enough to make it appear plausible.
    */
    ret= ISO_FILE_CANT_WRITE;
+#endif
+
    if(ret >= 0)
      ret = -1;
    sprintf(msg, "ds_read_block(%lu) returns %d", (unsigned long) lba, ret);