proka_exec/
lib.rs

1//! The proka executable header definitions.
2#![no_std]
3
4pub mod header;
5pub mod sections;
6pub mod utils;
7
8use header::Header;
9use sections::{SectionIter, Section};
10pub use utils::*;
11
12/// The header size.
13pub const HEADER_SIZE: usize = core::mem::size_of::<Header>();
14
15/// The section entry size
16pub const SECTION_SIZE: usize = core::mem::size_of::<Section>();
17
18/// The parser of the proka executable.
19///
20/// # Usage
21/// To use this parser, you must put an slice into the initializations.
22///
23/// If the content of the proka executable is in memory, the best way
24/// is to use `core::slice::from_raw_parts`.
25#[derive(Debug, Clone, Copy)]
26pub struct Parser {
27    buf: &'static [u8],
28    header: Header,
29    total_sections: u16,
30}
31
32impl Parser {
33    /// Initialize the parser by passing an slice.
34    ///
35    /// # Safety
36    /// You must ensure these before invoking this function:
37    ///
38    ///  - The slice's content is a valid executable;
39    ///  - The slice's pointer is accessable and mapped;
40    ///  - The slice's length is larger than 128 bytes.
41    ///
42    /// If this crate has used by kernel, you need to do mapping 
43    /// first, and invoke this.
44    pub unsafe fn init(buf: &'static [u8]) -> Result<Self, Error> {
45        let header_raw = &buf[0..HEADER_SIZE];    // Header length
46        let header = unsafe { *(header_raw.as_ptr() as *const Header) };
47
48        // Check: Validate is this correct executable
49        if !header.validate() {
50            return Err(Error::NotValidExecutable);
51        }
52        
53        Ok(Self {
54            buf, header,
55            total_sections: header.sections,
56        })
57    }
58
59    /// Get the header.
60    #[inline]
61    pub fn header(&self) -> Header {
62        self.header
63    }
64
65    /// Get each section table.
66    #[allow(private_interfaces)]
67    pub fn sections(&self) -> SectionIter {
68        SectionIter {
69            buf: self.buf,
70            total: self.total_sections,
71            current: 0,
72        }
73    }
74}
75
76/// The error type of parsing header.
77#[repr(C)]
78#[derive(Debug, Clone, Copy, PartialEq, Eq)]
79pub enum Error {
80    /// The executable is not valid.
81    NotValidExecutable,
82
83    /// An unknown character in UTF-8 was found in 
84    /// parsing arrays
85    UnknownCharacter,
86}
proka_exec/lib.rs

proka_exec/
lib.rs
