use std::{
borrow::Cow,
fmt::{Debug, Display, Formatter},
};
pub mod mtd;
pub mod v1v2;
pub mod v3;
fn chrp_checksum_add(lhs: u8, rhs: u8) -> u8 {
let (out, carry) = lhs.overflowing_add(rhs);
if carry {
out + 1
} else {
out
}
}
fn slice_rstrip<'a, T: PartialEq<T>>(mut ts: &'a [T], t: &T) -> &'a [T] {
while let Some(last) = ts.last() {
if last == t {
ts = ts.split_last().unwrap().1;
} else {
break;
}
}
ts
}
fn slice_find<T: PartialEq<T>>(ts: &[T], t: &T) -> Option<usize> {
let mut ret = None;
for (i, v) in ts.iter().enumerate() {
if v == t {
ret = Some(i);
break;
}
}
ret
}
#[derive(Debug)]
pub enum Error {
ParseError,
SectionTooBig,
ApplyError(std::io::Error),
}
type Result<T> = std::result::Result<T, Error>;
#[derive(Clone, Copy, PartialEq)]
pub enum VarType {
Common,
System,
}
impl Display for VarType {
fn fmt(&self, f: &mut Formatter) -> std::fmt::Result {
match self {
&VarType::Common => write!(f, "common"),
&VarType::System => write!(f, "system"),
}
}
}
pub fn nvram_parse<'a>(nvr: &'a [u8]) -> Result<Box<dyn Nvram<'a> + 'a>> {
match (v3::Nvram::parse(nvr), v1v2::Nvram::parse(nvr)) {
(Ok(nvram_v3), Err(_)) => Ok(Box::new(nvram_v3)),
(Err(_), Ok(nvram_v1v2)) => Ok(Box::new(nvram_v1v2)),
_ => Err(Error::ParseError),
}
}
pub trait NvramWriter {
fn erase_if_needed(&mut self, offset: u32, size: usize);
fn write_all(&mut self, offset: u32, buf: &[u8]) -> std::io::Result<()>;
}
pub trait Nvram<'a> {
fn prepare_for_write(&mut self);
fn active_part_mut(&mut self) -> &mut dyn Partition<'a>;
fn partitions(&self) -> Box<dyn Iterator<Item = &dyn Partition<'a>> + '_>;
fn serialize(&self) -> Result<Vec<u8>>;
fn apply(&mut self, w: &mut dyn NvramWriter) -> Result<()>;
}
pub trait Partition<'a>: Display {
fn variables(&self) -> Box<dyn Iterator<Item = &dyn Variable<'a>> + '_>;
fn get_variable(&self, key: &[u8], typ: VarType) -> Option<&dyn Variable<'a>>;
fn insert_variable(&mut self, key: &[u8], value: Cow<'a, [u8]>, typ: VarType);
fn remove_variable(&mut self, key: &[u8], typ: VarType);
}
pub trait Variable<'a>: Display {
fn value(&self) -> Cow<'a, [u8]>;
}