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use std::io::{self, Read, Write};
pub mod ay;
pub mod mdr;
pub mod sna;
pub mod tap;
pub mod snapshot;
pub mod scr;
pub mod z80;
pub trait ReadExactEx: Read {
fn read_exact_or_to_end(&mut self, mut buf: &mut[u8]) -> io::Result<usize> {
let orig_len = buf.len();
while !buf.is_empty() {
match self.read(buf) {
Ok(0) => break,
Ok(n) => buf = &mut buf[n..],
Err(ref e) if e.kind() == io::ErrorKind::Interrupted => {}
Err(e) => return Err(e),
}
}
Ok(orig_len - buf.len())
}
fn read_exact_or_none(&mut self, buf: &mut [u8]) -> io::Result<bool> {
let bytes_read = self.read_exact_or_to_end(buf)?;
if bytes_read == 0 {
Ok(false)
}
else if bytes_read == buf.len() {
Ok(true)
}
else {
Err(io::Error::new(io::ErrorKind::UnexpectedEof, "failed to fill whole buffer"))
}
}
}
impl<R: Read> ReadExactEx for R {}
pub(crate) unsafe trait StructRead: Copy {
fn read_new_struct<R: Read>(rd: R) -> io::Result<Self> where Self: Default {
let mut obj = Self::default();
obj.read_struct(rd)?;
Ok(obj)
}
fn read_struct<R: Read>(&mut self, mut rd: R) -> io::Result<()> {
rd.read_exact(unsafe { struct_slice_mut(self) })
}
fn read_struct_or_nothing<R: ReadExactEx>(&mut self, mut rd: R) -> io::Result<bool> {
rd.read_exact_or_none(unsafe { struct_slice_mut(self) })
}
fn read_struct_with_limit<R: Read>(&mut self, mut rd: R, limit: usize) -> io::Result<()> {
let slice = unsafe { struct_slice_mut(self) };
rd.read_exact(&mut slice[0..limit])
}
}
pub(crate) unsafe trait StructWrite: Copy {
fn write_struct<W: Write>(&self, mut wr: W) -> io::Result<()> {
let slice = unsafe { struct_slice_ref(self) };
wr.write_all(slice)
}
fn write_struct_with_limit<W: Write>(&self, mut wr: W, limit: usize) -> io::Result<()> {
let slice = unsafe { struct_slice_ref(self) };
wr.write_all(&slice[0..limit])
}
}
unsafe fn struct_slice_mut<T: Copy>(obj: &mut T) -> &mut [u8] {
let len = core::mem::size_of::<T>() / core::mem::size_of::<u8>();
core::slice::from_raw_parts_mut(obj as *mut T as *mut u8, len)
}
unsafe fn struct_slice_ref<T: Copy>(obj: &T) -> &[u8] {
let len = core::mem::size_of::<T>() / core::mem::size_of::<u8>();
core::slice::from_raw_parts(obj as *const T as *const u8, len)
}