64 lines
1.6 KiB
Rust
64 lines
1.6 KiB
Rust
use anyhow::Result;
|
|
use rand::Rng;
|
|
use std::{
|
|
fs::{self, File},
|
|
io::{Read, Seek as _, SeekFrom, Write as _},
|
|
path::{Path, PathBuf},
|
|
};
|
|
|
|
use crate::emulator::SimId;
|
|
|
|
pub struct Cart {
|
|
pub file_path: PathBuf,
|
|
pub rom: Vec<u8>,
|
|
sram_file: File,
|
|
pub sram: Vec<u8>,
|
|
}
|
|
|
|
impl Cart {
|
|
pub fn load(file_path: &Path, sim_id: SimId) -> Result<Self> {
|
|
let rom = fs::read(file_path)?;
|
|
|
|
let mut sram_file = File::options()
|
|
.read(true)
|
|
.write(true)
|
|
.create(true)
|
|
.truncate(false)
|
|
.open(sram_path(file_path, sim_id))?;
|
|
|
|
let sram = if sram_file.metadata()?.len() == 0 {
|
|
// new SRAM file, randomize the contents
|
|
let mut sram = vec![0; 8 * 1024];
|
|
let mut rng = rand::rng();
|
|
for dst in sram.iter_mut().step_by(2) {
|
|
*dst = rng.random();
|
|
}
|
|
sram
|
|
} else {
|
|
let mut sram = Vec::with_capacity(8 * 1024);
|
|
sram_file.read_to_end(&mut sram)?;
|
|
sram
|
|
};
|
|
|
|
Ok(Cart {
|
|
file_path: file_path.to_path_buf(),
|
|
rom,
|
|
sram_file,
|
|
sram,
|
|
})
|
|
}
|
|
|
|
pub fn save_sram(&mut self) -> Result<()> {
|
|
self.sram_file.seek(SeekFrom::Start(0))?;
|
|
self.sram_file.write_all(&self.sram)?;
|
|
Ok(())
|
|
}
|
|
}
|
|
|
|
fn sram_path(file_path: &Path, sim_id: SimId) -> PathBuf {
|
|
match sim_id {
|
|
SimId::Player1 => file_path.with_extension("p1.sram"),
|
|
SimId::Player2 => file_path.with_extension("p2.sram"),
|
|
}
|
|
}
|