1 //! A simple example of parsing `.debug_info`.
2
3 use object::{Object, ObjectSection};
4 use std::{borrow, env, fs};
5
main()6 fn main() {
7 for path in env::args().skip(1) {
8 let file = fs::File::open(&path).unwrap();
9 let mmap = unsafe { memmap::Mmap::map(&file).unwrap() };
10 let object = object::File::parse(&*mmap).unwrap();
11 let endian = if object.is_little_endian() {
12 gimli::RunTimeEndian::Little
13 } else {
14 gimli::RunTimeEndian::Big
15 };
16 dump_file(&object, endian).unwrap();
17 }
18 }
19
dump_file(object: &object::File, endian: gimli::RunTimeEndian) -> Result<(), gimli::Error>20 fn dump_file(object: &object::File, endian: gimli::RunTimeEndian) -> Result<(), gimli::Error> {
21 // Load a section and return as `Cow<[u8]>`.
22 let load_section = |id: gimli::SectionId| -> Result<borrow::Cow<[u8]>, gimli::Error> {
23 match object.section_by_name(id.name()) {
24 Some(ref section) => Ok(section
25 .uncompressed_data()
26 .unwrap_or(borrow::Cow::Borrowed(&[][..]))),
27 None => Ok(borrow::Cow::Borrowed(&[][..])),
28 }
29 };
30 // Load a supplementary section. We don't have a supplementary object file,
31 // so always return an empty slice.
32 let load_section_sup = |_| Ok(borrow::Cow::Borrowed(&[][..]));
33
34 // Load all of the sections.
35 let dwarf_cow = gimli::Dwarf::load(&load_section, &load_section_sup)?;
36
37 // Borrow a `Cow<[u8]>` to create an `EndianSlice`.
38 let borrow_section: &dyn for<'a> Fn(
39 &'a borrow::Cow<[u8]>,
40 ) -> gimli::EndianSlice<'a, gimli::RunTimeEndian> =
41 &|section| gimli::EndianSlice::new(&*section, endian);
42
43 // Create `EndianSlice`s for all of the sections.
44 let dwarf = dwarf_cow.borrow(&borrow_section);
45
46 // Iterate over the compilation units.
47 let mut iter = dwarf.units();
48 while let Some(header) = iter.next()? {
49 println!(
50 "Unit at <.debug_info+0x{:x}>",
51 header.offset().as_debug_info_offset().unwrap().0
52 );
53 let unit = dwarf.unit(header)?;
54
55 // Iterate over the Debugging Information Entries (DIEs) in the unit.
56 let mut depth = 0;
57 let mut entries = unit.entries();
58 while let Some((delta_depth, entry)) = entries.next_dfs()? {
59 depth += delta_depth;
60 println!("<{}><{:x}> {}", depth, entry.offset().0, entry.tag());
61
62 // Iterate over the attributes in the DIE.
63 let mut attrs = entry.attrs();
64 while let Some(attr) = attrs.next()? {
65 println!(" {}: {:?}", attr.name(), attr.value());
66 }
67 }
68 }
69 Ok(())
70 }
71