Prototyped a dynamic library facility interface
This commit is contained in:
parent
78cddc83a4
commit
786ea3ffe6
|
@ -0,0 +1,199 @@
|
||||||
|
// 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);
|
||||||
|
}
|
||||||
|
}
|
|
@ -17,6 +17,14 @@ use prelude::*;
|
||||||
use task;
|
use task;
|
||||||
|
|
||||||
pub mod at_exit;
|
pub mod at_exit;
|
||||||
|
|
||||||
|
// Currently only works for *NIXes
|
||||||
|
#[cfg(target_os = "linux")]
|
||||||
|
#[cfg(target_os = "android")]
|
||||||
|
#[cfg(target_os = "macos")]
|
||||||
|
#[cfg(target_os = "freebsd")]
|
||||||
|
pub mod dynamic_lib;
|
||||||
|
|
||||||
pub mod global;
|
pub mod global;
|
||||||
pub mod finally;
|
pub mod finally;
|
||||||
pub mod weak_task;
|
pub mod weak_task;
|
||||||
|
|
Loading…
Reference in New Issue