1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143

use crate::ffi;
use std::ptr;

use std::fmt;
use std::fs;
use std::os::unix::io::AsRawFd;
use std::path::Path;

use super::Result;
use super::{CompileUnits, TypeUnits};

#[derive(Debug)]
pub struct Dwarf<'dw> {
    inner: *mut ffi::Dwarf,
    kind: DwarfKind<'dw>,
}

enum DwarfKind<'dw> {
    Raw,
    File(fs::File),
    Fd(&'dw dyn AsRawFd),
    Elf(&'dw libelf::Elf<'dw>),
}

impl<'elf> fmt::Debug for DwarfKind<'elf> {
    fn fmt(&self, fmt: &mut fmt::Formatter<'_>) -> fmt::Result {
        match *self {
            DwarfKind::Raw => fmt.debug_tuple("Raw").finish(),
            DwarfKind::File(ref f) => fmt.debug_tuple("File").field(f).finish(),
            DwarfKind::Fd(f) => fmt.debug_tuple("Fd").field(&f.as_raw_fd()).finish(),
            DwarfKind::Elf(e) => fmt.debug_tuple("Elf").field(&e).finish(),
        }
    }
}

impl<'dw> Dwarf<'dw> {
    #[inline]
    fn new(dwarf: *mut ffi::Dwarf, kind: DwarfKind<'dw>) -> Dwarf<'dw> {
        Dwarf {
            inner: dwarf,
            kind: kind,
        }
    }

    /// Open a `Dwarf` from a path.
    ///
    /// # Examples
    ///
    /// ```
    /// let exe = std::env::current_exe().unwrap();
    /// let dw = libdw::Dwarf::open(exe).unwrap();
    /// ```
    pub fn open<P: AsRef<Path>>(path: P) -> Result<Dwarf<'static>> {
        let file = fs::File::open(path)?;
        let raw_fd = file.as_raw_fd();
        let dwarf = ffi!(dwarf_begin(raw_fd, ffi::Dwarf_Cmd::DWARF_C_READ))?;
        Ok(Dwarf::new(dwarf, DwarfKind::File(file)))
    }

    /// Create a `Dwarf` from an open file.
    ///
    /// # Examples
    ///
    /// ```
    /// let exe = std::env::current_exe().unwrap();
    /// let f = std::fs::File::open(exe).unwrap();
    /// let dw = libdw::Dwarf::from_fd(&f).unwrap();
    /// ```
    #[inline]
    pub fn from_fd<FD: AsRawFd>(fd: &'dw FD) -> Result<Dwarf<'dw>> {
        let raw_fd = fd.as_raw_fd();
        let dwarf = ffi!(dwarf_begin(raw_fd, ffi::Dwarf_Cmd::DWARF_C_READ))?;
        Ok(Dwarf::new(dwarf, DwarfKind::Fd(fd)))
    }

    /// Create a `Dwarf` from an existing `Elf`.
    ///
    /// # Examples
    ///
    /// ```
    /// # extern crate libdw;
    /// # extern crate libelf;
    /// let exe = std::env::current_exe().unwrap();
    /// let elf = libelf::Elf::open(exe).unwrap();
    /// let dw = libdw::Dwarf::from_elf(&elf).unwrap();
    /// ```
    #[inline]
    pub fn from_elf(elf: &'dw libelf::Elf<'_>) -> Result<Dwarf<'dw>> {
        let ptr = elf.as_ptr();
        let dwarf = ffi!(dwarf_begin_elf(
            ptr,
            ffi::Dwarf_Cmd::DWARF_C_READ,
            ptr::null_mut()
        ))?;
        Ok(Dwarf::new(dwarf, DwarfKind::Elf(elf)))
    }

    /// Create a `Dwarf` from a raw FFI pointer.
    ///
    /// # Safety
    ///
    /// This function is unsafe because there is no guarantee that the given
    /// pointer is a valid `libdw` handle, nor whether the lifetime inferred
    /// is appropriate.  This does not take ownership of the underlying object,
    /// so the caller must ensure it outlives the returned `Dwarf` wrapper.
    #[inline]
    pub unsafe fn from_raw(dwarf: *mut ffi::Dwarf) -> Dwarf<'dw> {
        Dwarf::new(dwarf, DwarfKind::Raw)
    }

    #[inline]
    pub fn get_elf(&'dw self) -> libelf::Elf<'dw> {
        let elf = raw_ffi!(dwarf_getelf(self.as_ptr()));
        unsafe { libelf::Elf::from_raw(elf) }
    }

    #[inline]
    pub fn compile_units(&'dw self) -> CompileUnits<'dw> {
        CompileUnits::new(self)
    }

    #[inline]
    pub fn type_units(&'dw self) -> TypeUnits<'dw> {
        TypeUnits::new(self)
    }

    #[inline]
    pub fn as_ptr(&self) -> *mut ffi::Dwarf {
        self.inner
    }
}

impl<'dw> Drop for Dwarf<'dw> {
    #[inline]
    fn drop(&mut self) {
        match self.kind {
            DwarfKind::Raw => (),
            _ => {
                raw_ffi!(dwarf_end(self.as_ptr()));
            }
        }
    }
}