288 lines
9.0 KiB
Rust
288 lines
9.0 KiB
Rust
//! Binary data conversion utilities.
|
|
|
|
use crate::durandal::{err::*, text::mac_roman_conv};
|
|
use std::{fmt, num::NonZeroU16};
|
|
|
|
#[doc(hidden)]
|
|
#[macro_export]
|
|
macro_rules! _durandal_read_impl {
|
|
// big endian
|
|
(BE $b:ident $nam:ident u16 $n:expr) => {
|
|
_durandal_read_impl!($b u16::from_be_bytes, $nam 2 $n);
|
|
};
|
|
(BE $b:ident $nam:ident i16 $n:expr) => {
|
|
_durandal_read_impl!($b i16::from_be_bytes, $nam 2 $n);
|
|
};
|
|
(BE $b:ident $nam:ident u32 $n:expr) => {
|
|
_durandal_read_impl!($b u32::from_be_bytes, $nam 4 $n);
|
|
};
|
|
(BE $b:ident $nam:ident i32 $n:expr) => {
|
|
_durandal_read_impl!($b i32::from_be_bytes, $nam 4 $n);
|
|
};
|
|
|
|
// little endian
|
|
(LE $b:ident $nam:ident u16 $n:expr) => {
|
|
_durandal_read_impl!($b u16::from_le_bytes $nam 2 $n);
|
|
};
|
|
(LE $b:ident $nam:ident i16 $n:expr) => {
|
|
_durandal_read_impl!($b i16::from_le_bytes $nam 2 $n);
|
|
};
|
|
(LE $b:ident $nam:ident u32 $n:expr) => {
|
|
_durandal_read_impl!($b u32::from_le_bytes $nam 4 $n);
|
|
};
|
|
(LE $b:ident $nam:ident i32 $n:expr) => {
|
|
_durandal_read_impl!($b i32::from_le_bytes $nam 4 $n);
|
|
};
|
|
|
|
// either endianness
|
|
($e:ident $b:ident $nam:ident Angle $n:expr) => {
|
|
_durandal_read_impl!($e $b $nam u16 $n);
|
|
let $nam = Angle::from_bits($nam);
|
|
};
|
|
($e:ident $b:ident $nam:ident Fixed $n:expr) => {
|
|
_durandal_read_impl!($e $b $nam u32 $n);
|
|
let $nam = Fixed::from_bits($nam);
|
|
};
|
|
($e:ident $b:ident $nam:ident Unit $n:expr) => {
|
|
_durandal_read_impl!($e $b $nam u16 $n);
|
|
let $nam = Unit::from_bits($nam);
|
|
};
|
|
($e:ident $b:ident $nam:ident OptU16 $n:expr) => {
|
|
_durandal_read_impl!($e $b $nam u16 $n);
|
|
let $nam = OptU16::from_repr($nam);
|
|
};
|
|
($e:ident $b:ident $nam:ident usize u16 $n:expr) => {
|
|
_durandal_read_impl!($e $b $nam u16 $n);
|
|
let $nam = usize::from($nam);
|
|
};
|
|
($e:ident $b:ident $nam:ident usize u32 $n:expr) => {
|
|
_durandal_read_impl!($e $b $nam u32 $n);
|
|
let $nam = usize_from_u32($nam);
|
|
};
|
|
|
|
// no endianness
|
|
($_:ident $b:ident $nam:ident u8 $n:expr) => {let $nam = $b[$n];};
|
|
($_:ident $b:ident $nam:ident slice u8 $n:expr) => {let $nam = &$b[$n];};
|
|
($_:ident $b:ident $nam:ident i8 $n:expr) => {
|
|
let $nam = i8::from_ne_bytes([$b[$n]]);
|
|
};
|
|
($_:ident $b:ident $nam:ident Ident $n:expr) => {
|
|
let $nam = Ident([$b[$n], $b[$n + 1], $b[$n + 2], $b[$n + 3]]);
|
|
};
|
|
($_:ident $b:ident $nam:ident $f:ident $n:expr) => {
|
|
let $nam = $f(&$b[$n])?;
|
|
};
|
|
($_:ident $b:ident $nam:ident no_try $f:ident $n:expr) => {
|
|
let $nam = $f(&$b[$n]);
|
|
};
|
|
|
|
// worker - creates let statement
|
|
($b:ident $pth:path , $nam:ident 2 $n:expr) => {
|
|
let $nam = $pth([$b[$n], $b[$n + 1]]);
|
|
};
|
|
($b:ident $pth:path , $nam:ident 4 $n:expr) => {
|
|
let $nam = $pth([$b[$n], $b[$n + 1], $b[$n + 2], $b[$n + 3]]);
|
|
};
|
|
}
|
|
|
|
/// Reads structured data from a byte slice.
|
|
///
|
|
/// First start by specifying the endianness, size and source using the syntax
|
|
/// `endian, size in source =>` where:
|
|
///
|
|
/// - `endian` is `BE` or `LE` for big- or little-endian respectively.
|
|
/// - `size` is an expression specifying the last index that should be used by
|
|
/// this macro in `source`.
|
|
/// - `source` is a `u8` slice to read data from.
|
|
///
|
|
/// After the initializer line, all lines have the syntax
|
|
/// `name = type[place] opts;` where:
|
|
///
|
|
/// - `name` is the binding to put the resulting data in.
|
|
/// - `type` is one of:
|
|
/// - `u8` or `i8`: one byte will be read at `place`.
|
|
/// - `u16` or `i16`: two bytes will be read at `place` with `from_*_bytes`.
|
|
/// - `u32` or `i32`: four bytes will be read at `place` with `from_*_bytes`.
|
|
/// - `Ident`: four bytes will be read at `place` into an array, disregarding
|
|
/// endianness, creating an `Ident` object.
|
|
/// - `Angle`: same as `u16`, but the result is passed to
|
|
/// `fixed::Angle::from_bits`, resulting in a `fixed::Angle` object.
|
|
/// - `Fixed`: same as `u32`, but the result is passed to
|
|
/// `fixed::Fixed::from_bits`, resulting in a `fixed::Fixed` object.
|
|
/// - `Unit`: same as `u16`, but the result is passed to
|
|
/// `fixed::Unit::from_bits`, resulting in a `fixed::Unit` object.
|
|
/// - `OptU16`: same as `u16`, but the result is passed to
|
|
/// `OptU16::from_repr`, resulting in an `OptU16` object.
|
|
/// - The name of a function, which is passed `&source[place]` as its only
|
|
/// argument. The function's result has the `?` operator applied to it.
|
|
/// - `opts` may be one of:
|
|
/// - `slice` when `type` is `u8`: `place` is a range specifying a `u8` slice
|
|
/// to be taken from `source`.
|
|
/// - `usize` when `type` is `u16` or `u32`: converts the resulting integer to
|
|
/// `usize` by `usize_to_u32` for `u32` or by `from` for `u16`.
|
|
/// - `no_try` when `type` is a function name: does not use the `?` operator
|
|
/// on the resulting function call.
|
|
/// - Nothing at all.
|
|
/// - `place` is either an integer literal which must be representable as
|
|
/// `usize`, or a range, which may only be used when `type` is a function
|
|
/// name.
|
|
#[macro_export]
|
|
macro_rules! read_data {
|
|
(
|
|
$sz:expr , $ty:ident in $b:ident =>
|
|
$( $nam:ident = $t:ident [ $n:expr ] $( $ex:ident )* ; )*
|
|
) => {
|
|
if $b.len() < $sz {
|
|
bail!("not enough data");
|
|
}
|
|
|
|
$($crate::_durandal_read_impl!($ty $b $nam $($ex)* $t $n);)*
|
|
};
|
|
}
|
|
|
|
/// Casts a `u32` to a `usize`. For future compatibility.
|
|
#[inline]
|
|
pub const fn usize_from_u32(n: u32) -> usize {n as usize}
|
|
|
|
/// Creates an `Ident` from a slice.
|
|
///
|
|
/// `b` must be at least 4 bytes, or a panic will occur.
|
|
pub fn ident(b: &[u8]) -> Ident {Ident([b[0], b[1], b[2], b[3]])}
|
|
|
|
/// Applies `u32::from_be_bytes` to a slice.
|
|
///
|
|
/// `b` must be at least 4 bytes, or a panic will occur.
|
|
pub fn u32b(b: &[u8]) -> u32 {u32::from_be_bytes([b[0], b[1], b[2], b[3]])}
|
|
|
|
/// Applies `u16::from_be_bytes` to a slice.
|
|
///
|
|
/// `b` must be at least 2 bytes, or a panic will occur.
|
|
pub fn u16b(b: &[u8]) -> u16 {u16::from_be_bytes([b[0], b[1]])}
|
|
|
|
/// Applies `i32::from_be_bytes` to a slice.
|
|
///
|
|
/// `b` must be at least 4 bytes, or a panic will occur.
|
|
pub fn i32b(b: &[u8]) -> i32 {i32::from_be_bytes([b[0], b[1], b[2], b[3]])}
|
|
|
|
/// Applies `i16::from_be_bytes` to a slice.
|
|
///
|
|
/// `b` must be at least 2 bytes, or a panic will occur.
|
|
pub fn i16b(b: &[u8]) -> i16 {i16::from_be_bytes([b[0], b[1]])}
|
|
|
|
/// Applies a read function over a slice.
|
|
///
|
|
/// Applies `read` over `b`, resulting in a vector of its return values. Each
|
|
/// iteration will pass a slice of `b` to `read` for it to read from, and then
|
|
/// increments the slice index by the second return value. When there is no
|
|
/// data left in `b`, the function returns.
|
|
pub fn rd_array<T, F>(b: &[u8], read: F) -> ResultS<Vec<T>>
|
|
where T: Sized,
|
|
F: Fn(&[u8]) -> ResultS<(T, usize)>
|
|
{
|
|
let mut v = Vec::new();
|
|
let mut p = 0;
|
|
|
|
while p < b.len() {
|
|
let (r, s) = read(&b[p..])?;
|
|
v.push(r);
|
|
p += s;
|
|
}
|
|
|
|
Ok(v)
|
|
}
|
|
|
|
/// Applies a read function over a slice with an offset table.
|
|
///
|
|
/// Applies `read` over each offset in `b`, of which there are `num` amount of
|
|
/// starting at `p`, resulting in a vector of its return values. Each iteration
|
|
/// reads a 32-bit big endian offset from `b`, and then passes a slice of `b`
|
|
/// to `read` starting at that offset. When all offsets have been read, the
|
|
/// function returns.
|
|
pub fn rd_ofstable<T, F>(b: &[u8],
|
|
mut p: usize,
|
|
num: usize,
|
|
read: F)
|
|
-> ResultS<Vec<T>>
|
|
where T: Sized,
|
|
F: Fn(&[u8]) -> ResultS<T>
|
|
{
|
|
let mut v = Vec::with_capacity(num);
|
|
|
|
for _ in 0..num {
|
|
let ofs = usize_from_u32(u32b(&b[p..p + 4]));
|
|
|
|
if ofs >= b.len() {
|
|
bail!("not enough data");
|
|
}
|
|
|
|
v.push(read(&b[ofs..])?);
|
|
p += 4;
|
|
}
|
|
|
|
Ok(v)
|
|
}
|
|
|
|
impl OptU16
|
|
{
|
|
/// Creates an `OptU16` representing `None`.
|
|
pub const fn none() -> Self {OptU16(None)}
|
|
|
|
/// Creates an `OptU16` from a `u16`.
|
|
pub fn from_repr(n: u16) -> Self
|
|
{
|
|
if n == u16::max_value() {
|
|
Self(None)
|
|
} else {
|
|
Self(NonZeroU16::new(n + 1))
|
|
}
|
|
}
|
|
|
|
/// Returns the `u16` representation.
|
|
pub fn get_repr(&self) -> u16
|
|
{
|
|
match self.0 {
|
|
None => u16::max_value(),
|
|
Some(n) => n.get() - 1,
|
|
}
|
|
}
|
|
|
|
/// Returns the `Option` representation.
|
|
pub fn get(&self) -> Option<u16>
|
|
{
|
|
match self.0 {
|
|
None => None,
|
|
Some(n) => Some(n.get() - 1),
|
|
}
|
|
}
|
|
}
|
|
|
|
impl fmt::Debug for OptU16
|
|
{
|
|
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result
|
|
{
|
|
match self.get() {
|
|
None => write!(f, "None"),
|
|
Some(n) => write!(f, "Some({})", n),
|
|
}
|
|
}
|
|
}
|
|
|
|
impl fmt::Debug for Ident
|
|
{
|
|
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result
|
|
{
|
|
write!(f, "\"{}\"", mac_roman_conv(&self.0))
|
|
}
|
|
}
|
|
|
|
/// A four-character-code identifier.
|
|
#[derive(serde::Serialize, serde::Deserialize)]
|
|
pub struct Ident(pub [u8; 4]);
|
|
|
|
/// An object identified by a `u16` which may be `u16::max_value()` to
|
|
/// represent a nulled value.
|
|
#[derive(serde::Serialize, serde::Deserialize)]
|
|
pub struct OptU16(Option<NonZeroU16>);
|
|
|
|
// EOF
|