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
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172

// x11-rs: Rust bindings for X11 libraries
// The X11 libraries are available under the MIT license.
// These bindings are public domain.

use std::ffi::{ CStr, CString };
use std::path::Path;
use std::os::raw::{ c_char, c_void };

use libc;

use error::{ OpenError, OpenErrorKind };

include!(concat!(env!("OUT_DIR"), "/config.rs"));

//
// x11_link!
//

macro_rules! x11_link {
  { $struct_name:ident, $pkg_name:ident, [$($lib_name:expr),*], $nsyms:expr,
    $(pub fn $fn_name:ident ($($param_name:ident : $param_type:ty),*) -> $ret_type:ty,)*
    variadic:
    $(pub fn $vfn_name:ident ($($vparam_name: ident : $vparam_type:ty),+) -> $vret_type:ty,)*
    globals:
    $(pub static $var_name:ident : $var_type:ty,)*
  } => {
    pub struct $struct_name {
      #[allow(dead_code)]
      lib: ::link::DynamicLibrary,
      $(pub $fn_name: unsafe extern "C" fn ($($param_type),*) -> $ret_type,)*
      $(pub $vfn_name: unsafe extern "C" fn ($($vparam_type),+, ...) -> $vret_type,)*
      $(pub $var_name: *mut $var_type,)*
    }

    unsafe impl Send for $struct_name {}
    unsafe impl Sync for $struct_name {}

    impl $struct_name {
      unsafe fn init (this: *mut Self) -> Result<(), $crate::error::OpenError> {
        lazy_static! {
          static ref SYMS: [(&'static str, usize); $nsyms] = unsafe {[
            $((stringify!($fn_name), &((*(0 as *const $struct_name)).$fn_name) as *const _ as usize),)*
            $((stringify!($vfn_name), &((*(0 as *const $struct_name)).$vfn_name) as *const _ as usize),)*
            $((stringify!($var_name), &((*(0 as *const $struct_name)).$var_name) as *const _ as usize),)*
          ]};
        }
        let offset = this as usize;
        for &(name, sym_offset) in SYMS.iter() {
          *((offset + sym_offset) as *mut *mut _) = try!((*this).lib.symbol(name));
        }
        Ok(())
      }

      pub fn open () -> Result<$struct_name, $crate::error::OpenError> {
        unsafe {
          let libdir = $crate::link::config::libdir::$pkg_name;
          let lib = try!($crate::link::DynamicLibrary::open_multi(libdir, &[$($lib_name),*]));
          let mut this = ::maybe_uninit::MaybeUninit::<$struct_name>::uninit();
          let this_ptr = this.as_mut_ptr();
          ::std::ptr::write(&mut (*this_ptr).lib, lib);
          try!(Self::init(this_ptr));
          Ok(this.assume_init())
        }
      }
    }
  };
}


//
// DynamicLibrary
//


pub struct DynamicLibrary {
  handle: *mut c_void,
}

impl DynamicLibrary {
  pub fn open (name: &str) -> Result<DynamicLibrary, OpenError> {
    unsafe {
      let cname = match CString::new(name) {
        Ok(cname) => cname,
        Err(_) => {
          return Err(OpenError::new(OpenErrorKind::Library,
                                    String::from("library name contains NUL byte(s)")));
        },
      };

      let handle = libc::dlopen(cname.as_ptr(), libc::RTLD_LAZY);

      if handle.is_null() {
        let msg = libc::dlerror();

        if msg.is_null() {
          return Err(OpenError::new(OpenErrorKind::Library, String::new()));
        }

        let cmsg = CStr::from_ptr(msg as *const c_char);
        let detail = cmsg.to_string_lossy().into_owned();
        return Err(OpenError::new(OpenErrorKind::Library, detail));
      }

      Ok(DynamicLibrary { handle: handle as *mut c_void })
    }
  }

  pub fn open_multi (libdir: Option<&'static str>, names: &[&str]) -> Result<DynamicLibrary, OpenError> {
    assert!(!names.is_empty());

    let paths = libdir.map_or(Vec::new(), |dir| {
        let path = Path::new(dir);
        names.iter().map(|name| path.join(name).to_str().unwrap().to_string()).collect::<Vec<_>>()
    });

    let mut msgs = Vec::new();

    for name in names.iter().map(|x| *x).chain(paths.iter().map(|x| &**x)) {
      match DynamicLibrary::open(name) {
        Ok(lib) => { return Ok(lib); },
        Err(err) => { msgs.push(format!("{}", err)); },
      }
    }

    let mut detail = String::new();

    for i in 0..msgs.len() {
      if i != 0 {
        detail.push_str("; ");
      }
      detail.push_str(msgs[i].as_ref());
    }

    Err(OpenError::new(OpenErrorKind::Library, detail))
  }

  pub fn symbol (&self, name: &str) -> Result<*mut c_void, OpenError> {
    unsafe {
      let cname = match CString::new(name) {
        Ok(cname) => cname,
        Err(_) => {
          return Err(OpenError::new(OpenErrorKind::Symbol,
                                    String::from("symbol name contains NUL byte(s)")));
        },
      };

      let sym = libc::dlsym(self.handle as *mut _, cname.as_ptr());

      if sym.is_null() {
        let msg = libc::dlerror();

        if msg.is_null() {
          return Err(OpenError::new(OpenErrorKind::Symbol, String::from(name)));
        }

        let cmsg = CStr::from_ptr(msg as *const c_char);
        let detail = format!("{} - {}", name, cmsg.to_string_lossy().into_owned());;
        return Err(OpenError::new(OpenErrorKind::Symbol, detail));
      }

      Ok(sym as *mut c_void)
    }
  }
}

impl Drop for DynamicLibrary {
  fn drop (&mut self) {
    unsafe {
      libc::dlclose(self.handle as *mut _);
    }
  }
}