crc_one_byte     1400 contrib/tools/pngfix.c          crc = crc_one_byte(crc, ch);
crc_one_byte     3065 contrib/tools/pngfix.c          crc = crc_one_byte(crc, file_crc >> 24);
crc_one_byte     3433 contrib/tools/pngfix.c                   chunk->write_crc = crc_one_byte(chunk->write_crc, b);