#dwarf #elf

no-std bin+lib dwat

A library for accessing DWARF v4/v5 type information

14 releases (5 breaking)

0.6.4 Mar 24, 2024
0.6.3 Jan 13, 2024
0.5.0 Jan 7, 2024
0.4.2 Jan 6, 2024
0.1.3 Jan 2, 2024

#16 in #dwarf

Download history 56/week @ 2024-07-27 28/week @ 2024-09-21 10/week @ 2024-09-28

715 downloads per month

BSD-2-Clause

97KB
2.5K SLoC

dwat

A fairly performant library intended to make DWARF (v4/v5) debugging information more accessible.

My focus so far has been on making the type information (specifically structs) present in DWARF info easier to work with, so functionality related to that is largely what is implemented at this point.

Current Features:

  • Get a list of types by name
  • Get a map of types by name
  • Lookup types by name
  • Formating of parsed struct and union information to C-style definitions
  • Get members of structs/unions
  • Get underlying types of modifiers (volatile/const/etc...)
  • Get byte size information for types
  • Get bit sizes for bit field struct members

CLI

Though dwat is primarily meant to be a library, a basic cli is included:

Usage: dwat <COMMAND>

Commands:
  lookup  Find and display a single struct
  dump    Find and display all structs
  help    Print this message or the help of the given subcommand(s)

Options:
  -h, --help  Print help

Python bindings

dwat has python bindings! The documentation can be found here: https://zolutal.github.io/dwat/

Examples

There are several examples in the examples directory that are worth checking out.

Usage

The first step of using the library is to load the file containing DWARF info into memory, then invoke Dwarf::load:

    let file = File::open(path)?;
    let mmap = unsafe { Mmap::map(&file) }?;

    let dwarf = Dwarf::load(&*mmap)?;

The dwarf object has a lookup_type method that can be used to lookup any type implementing the Tagged trait by name, in this case a struct will be searched for:

    let found = dwarf.lookup_type::<dwat::Struct>(struct_name)?;

Struct members can then be retrieved by calling .members() which returns a Vector of Member structs.

    let members = struc.members(&dwarf)?;

A struct object can be converted to a C-style definition String by invoking the to_string function:

    if let Some(found) = found {
        println!("{}", found.to_string(&dwarf)?);
    }

Dependencies

~5–15MB
~214K SLoC