--- /dev/null
+// Copyright 2013 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+/*!
+
+Dynamic library facilities.
+
+A simple wrapper over the platforms dynamic library facilities
+
+*/
+use ptr;
+use cast;
+use path;
+use libc;
+use ops::*;
+use option::*;
+use result::*;
+
+pub struct DynamicLibrary { priv handle: *libc::c_void }
+
+impl Drop for DynamicLibrary {
+ fn finalize(&self) {
+ match do dl::check_for_errors_in {
+ unsafe {
+ dl::close(self.handle)
+ }
+ } {
+ Ok(()) => { },
+ Err(str) => fail!(str)
+ }
+ }
+}
+
+impl DynamicLibrary {
+ /// Lazily open a dynamic library. When passed None it gives a
+ /// handle to the calling process
+ pub fn open(filename: Option<&path::Path>) -> Result<DynamicLibrary, ~str> {
+ let open_wrapper = |raw_ptr| {
+ do dl::check_for_errors_in {
+ unsafe {
+ DynamicLibrary { handle: dl::open(raw_ptr) }
+ }
+ }
+ };
+
+ match filename {
+ Some(name) => do name.to_str().as_c_str |raw_name| {
+ open_wrapper(raw_name)
+ },
+ None => open_wrapper(ptr::null())
+ }
+ }
+
+ /// Access the value at the symbol of the dynamic library
+ pub unsafe fn symbol<T>(&self, symbol: &str) -> Result<T, ~str> {
+ // This function should have a lifetime constraint of 'self on
+ // T but that feature is still unimplemented
+
+ do dl::check_for_errors_in {
+ let symbol_value = do symbol.as_c_str |raw_string| {
+ dl::symbol(self.handle, raw_string)
+ };
+
+ cast::transmute(symbol_value)
+ }
+ }
+}
+
+#[test]
+priv fn test_loading_cosine () {
+ // The math library does not need to be loaded since it is already
+ // statically linked in
+ let libm = match DynamicLibrary::open(None) {
+ Err (error) => fail!("Could not load self as module: %s", error),
+ Ok (libm) => libm
+ };
+
+ // Unfortunately due to issue #6194 it is not possible to call
+ // this as a C function
+ let cosine: extern fn(libc::c_double) -> libc::c_double = unsafe {
+ match libm.symbol("cos") {
+ Err (error) => fail!("Could not load function cos: %s", error),
+ Ok (cosine) => cosine
+ }
+ };
+
+ let argument = 0.0;
+ let expected_result = 1.0;
+ let result = cosine(argument);
+ if result != expected_result {
+ fail!("cos(%?) != %? but equaled %? instead", argument,
+ expected_result, result)
+ }
+}
+
+#[cfg(target_os = "linux")]
+#[cfg(target_os = "android")]
+#[cfg(target_os = "macos")]
+#[cfg(target_os = "freebsd")]
+mod dl {
+ use libc;
+ use ptr;
+ use str;
+ use task;
+ use result::*;
+
+ pub unsafe fn open(filename: *libc::c_char) -> *libc::c_void {
+ dlopen(filename, Lazy as libc::c_int)
+ }
+
+ pub fn check_for_errors_in<T>(f: &fn()->T) -> Result<T, ~str> {
+ unsafe {
+ do task::atomically {
+ let _old_error = dlerror();
+
+ let result = f();
+
+ let last_error = dlerror();
+ if ptr::null() == last_error {
+ Ok(result)
+ } else {
+ Err(str::raw::from_c_str(last_error))
+ }
+ }
+ }
+ }
+
+ pub unsafe fn symbol(handle: *libc::c_void, symbol: *libc::c_char) -> *libc::c_void {
+ dlsym(handle, symbol)
+ }
+ pub unsafe fn close(handle: *libc::c_void) {
+ dlclose(handle); ()
+ }
+
+ pub enum RTLD {
+ Lazy = 1,
+ Now = 2,
+ Global = 256,
+ Local = 0,
+ }
+
+ #[link_name = "dl"]
+ extern {
+ fn dlopen(filename: *libc::c_char, flag: libc::c_int) -> *libc::c_void;
+ fn dlerror() -> *libc::c_char;
+ fn dlsym(handle: *libc::c_void, symbol: *libc::c_char) -> *libc::c_void;
+ fn dlclose(handle: *libc::c_void) -> libc::c_int;
+ }
+}
+
+#[cfg(target_os = "win32")]
+mod dl {
+ use os;
+ use libc;
+ use task;
+ use result::*;
+
+ pub unsafe fn open(filename: *libc::c_char) -> *libc::c_void {
+ LoadLibrary(filename)
+ }
+
+ pub fn check_for_errors_in<T>(f: &fn()->T) -> Result<T, ~str> {
+ unsafe {
+ do task::atomically {
+ SetLastError(0);
+
+ let result = f();
+
+ let error = os::errno();
+ if 0 == error {
+ Ok(result)
+ } else {
+ Err(fmt!("Error code %?", error))
+ }
+ }
+ }
+ }
+ pub unsafe fn symbol(handle: *libc::c_void, symbol: *libc::c_char) -> *libc::c_void {
+ GetProcAddress(handle, symbol)
+ }
+ pub unsafe fn close(handle: *libc::c_void) {
+ FreeLibrary(handle); ()
+ }
+
+ #[link_name = "kernel32"]
+ extern "stdcall" {
+ fn SetLastError(error: u32);
+ fn LoadLibrary(name: *libc::c_char) -> *libc::c_void;
+ fn GetProcAddress(handle: *libc::c_void, name: *libc::c_char) -> *libc::c_void;
+ fn FreeLibrary(handle: *libc::c_void);
+ }
+}