1 // Copyright 2013 The Rust Project Developers. See the COPYRIGHT
2 // file at the top-level directory of this distribution and at
3 // http://rust-lang.org/COPYRIGHT.
5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
8 // option. This file may not be copied, modified, or distributed
9 // except according to those terms.
13 Dynamic library facilities.
15 A simple wrapper over the platforms dynamic library facilities
26 pub struct DynamicLibrary { priv handle: *libc::c_void }
28 impl Drop for DynamicLibrary {
30 match do dl::check_for_errors_in {
32 dl::close(self.handle)
36 Err(str) => fail!(str)
42 /// Lazily open a dynamic library. When passed None it gives a
43 /// handle to the calling process
44 pub fn open(filename: Option<&path::Path>) -> Result<DynamicLibrary, ~str> {
46 let maybe_library = do dl::check_for_errors_in {
48 Some(name) => dl::open_external(name),
49 None => dl::open_internal()
53 // The dynamic library must not be constructed if there is
54 // an error opening the library so the destructor does not
58 Ok(handle) => Ok(DynamicLibrary { handle: handle })
63 /// Access the value at the symbol of the dynamic library
64 pub unsafe fn symbol<T>(&self, symbol: &str) -> Result<T, ~str> {
65 // This function should have a lifetime constraint of 'self on
66 // T but that feature is still unimplemented
68 let maybe_symbol_value = do dl::check_for_errors_in {
69 do symbol.with_c_str |raw_string| {
70 dl::symbol(self.handle, raw_string)
74 // The value must not be constructed if there is an error so
75 // the destructor does not run.
76 match maybe_symbol_value {
78 Ok(symbol_value) => Ok(cast::transmute(symbol_value))
93 // #[ignore(cfg(windows))] // FIXME #8818
94 #[ignore] // FIXME #9137 this library isn't thread-safe
95 fn test_loading_cosine() {
96 // The math library does not need to be loaded since it is already
97 // statically linked in
98 let libm = match DynamicLibrary::open(None) {
99 Err(error) => fail!("Could not load self as module: %s", error),
103 // Unfortunately due to issue #6194 it is not possible to call
104 // this as a C function
105 let cosine: extern fn(libc::c_double) -> libc::c_double = unsafe {
106 match libm.symbol("cos") {
107 Err(error) => fail!("Could not load function cos: %s", error),
113 let expected_result = 1.0;
114 let result = cosine(argument);
115 if result != expected_result {
116 fail!("cos(%?) != %? but equaled %? instead", argument,
117 expected_result, result)
122 #[cfg(target_os = "linux")]
123 #[cfg(target_os = "macos")]
124 #[cfg(target_os = "freebsd")]
125 #[ignore] // FIXME #9137 this library isn't thread-safe
126 fn test_errors_do_not_crash() {
127 // Open /dev/null as a library to get an error, and make sure
128 // that only causes an error, and not a crash.
129 let path = GenericPath::from_str("/dev/null");
130 match DynamicLibrary::open(Some(&path)) {
132 Ok(_) => fail!("Successfully opened the empty library.")
137 #[cfg(target_os = "linux")]
138 #[cfg(target_os = "android")]
139 #[cfg(target_os = "macos")]
140 #[cfg(target_os = "freebsd")]
147 use unstable::sync::atomically;
150 pub unsafe fn open_external(filename: &path::Path) -> *libc::c_void {
151 #[fixed_stack_segment]; #[inline(never)];
152 do filename.with_c_str |raw_name| {
153 dlopen(raw_name, Lazy as libc::c_int)
157 pub unsafe fn open_internal() -> *libc::c_void {
158 #[fixed_stack_segment]; #[inline(never)];
160 dlopen(ptr::null(), Lazy as libc::c_int)
163 pub fn check_for_errors_in<T>(f: &fn()->T) -> Result<T, ~str> {
164 #[fixed_stack_segment]; #[inline(never)];
168 let _old_error = dlerror();
172 let last_error = dlerror();
173 if ptr::null() == last_error {
176 Err(str::raw::from_c_str(last_error))
182 pub unsafe fn symbol(handle: *libc::c_void, symbol: *libc::c_char) -> *libc::c_void {
183 #[fixed_stack_segment]; #[inline(never)];
185 dlsym(handle, symbol)
187 pub unsafe fn close(handle: *libc::c_void) {
188 #[fixed_stack_segment]; #[inline(never)];
202 fn dlopen(filename: *libc::c_char, flag: libc::c_int) -> *libc::c_void;
203 fn dlerror() -> *libc::c_char;
204 fn dlsym(handle: *libc::c_void, symbol: *libc::c_char) -> *libc::c_void;
205 fn dlclose(handle: *libc::c_void) -> libc::c_int;
209 #[cfg(target_os = "win32")]
215 use unstable::sync::atomically;
218 pub unsafe fn open_external(filename: &path::Path) -> *libc::c_void {
219 #[fixed_stack_segment]; #[inline(never)];
220 do os::win32::as_utf16_p(filename.to_str()) |raw_name| {
221 LoadLibraryW(raw_name)
225 pub unsafe fn open_internal() -> *libc::c_void {
226 #[fixed_stack_segment]; #[inline(never)];
227 let handle = ptr::null();
228 GetModuleHandleExW(0 as libc::DWORD, ptr::null(), &handle as **libc::c_void);
232 pub fn check_for_errors_in<T>(f: &fn()->T) -> Result<T, ~str> {
233 #[fixed_stack_segment]; #[inline(never)];
240 let error = os::errno();
244 Err(fmt!("Error code %?", error))
249 pub unsafe fn symbol(handle: *libc::c_void, symbol: *libc::c_char) -> *libc::c_void {
250 #[fixed_stack_segment]; #[inline(never)];
251 GetProcAddress(handle, symbol)
253 pub unsafe fn close(handle: *libc::c_void) {
254 #[fixed_stack_segment]; #[inline(never)];
255 FreeLibrary(handle); ()
258 #[cfg(target_arch = "x86")]
259 #[link_name = "kernel32"]
261 fn SetLastError(error: u32);
262 fn LoadLibraryW(name: *u16) -> *libc::c_void;
263 fn GetModuleHandleExW(dwFlags: libc::DWORD, name: *u16,
264 handle: **libc::c_void) -> *libc::c_void;
265 fn GetProcAddress(handle: *libc::c_void, name: *libc::c_char) -> *libc::c_void;
266 fn FreeLibrary(handle: *libc::c_void);
269 #[cfg(target_arch = "x86_64")]
270 #[link_name = "kernel32"]
272 fn SetLastError(error: u32);
273 fn LoadLibraryW(name: *u16) -> *libc::c_void;
274 fn GetModuleHandleExW(dwFlags: libc::DWORD, name: *u16,
275 handle: **libc::c_void) -> *libc::c_void;
276 fn GetProcAddress(handle: *libc::c_void, name: *libc::c_char) -> *libc::c_void;
277 fn FreeLibrary(handle: *libc::c_void);