fix(cart): improve title parsin

Now both Tokimeki Memorial titles are read properly
This commit is contained in:
Rekai Nyangadzayi Musuka 2021-10-30 15:48:47 +09:00
parent 4125ea5c74
commit 1526b4a09d
1 changed files with 11 additions and 6 deletions

View File

@ -5,7 +5,8 @@ use crate::bus::BusIo;
const RAM_SIZE_ADDRESS: usize = 0x0149;
const ROM_SIZE_ADDRESS: usize = 0x0148;
const MBC_TYPE_ADDRESS: usize = 0x0147;
const ROM_TITLE_RANGE: std::ops::RangeInclusive<usize> = 0x0134..=0x0143;
const ROM_TITLE_START: usize = 0x134;
const ROM_TITLE_MAX_SIZE: usize = 16;
#[derive(Debug, Default)]
pub(crate) struct Cartridge {
@ -59,13 +60,17 @@ impl Cartridge {
}
fn find_title(memory: &[u8]) -> Option<String> {
let slice = &memory[ROM_TITLE_RANGE];
let with_nulls = std::str::from_utf8(slice).ok();
let trimmed = with_nulls.map(|s| s.trim_matches('\0').trim());
let title_bytes = &memory[ROM_TITLE_START..(ROM_TITLE_START + ROM_TITLE_MAX_SIZE)];
match trimmed {
// ASCII Byte array purposely does not have null terminator
let ascii = match title_bytes.iter().position(|byte| *byte == 0x00) {
Some(end) => &memory[ROM_TITLE_START..(ROM_TITLE_START + end)],
None => &memory[ROM_TITLE_START..(ROM_TITLE_START + ROM_TITLE_MAX_SIZE - 1)],
};
match std::str::from_utf8(ascii).ok() {
Some("") | None => None,
Some(_) => trimmed.map(String::from),
Some(title) => Some(String::from(title)),
}
}