message: Improvements for dlfcn
diff: //! dlfcn implementation for Redox, following http://pubs.opengroup.org/onlinepubs/7908799/xsh/dlfcn.h.html
  use core::{ptr, str};
  +use core::sync::atomic::{AtomicUsize, ATOMIC_USIZE_INIT, Ordering};
  use c_str::CStr;
  use platform::types::*;
  @@ -10,6 +11,11 @@ pub const RTLD_NOW: c_int = 0x0002;
  pub const RTLD_GLOBAL: c_int = 0x0100;
  pub const RTLD_LOCAL: c_int = 0x0000;
  +static ERROR_NOT_SUPPORTED: &'static CStr = c_str!("dlfcn not supported");
  +
  +#[thread_local]
  +static ERROR: AtomicUsize = ATOMIC_USIZE_INIT;
  +
  #[repr(C)]
  pub struct Dl_info {
  dli_fname: *const c_char,
  @@ -29,14 +35,32 @@ pub unsafe extern "C" fn dladdr(addr: *mut c_void, info: *mut Dl_info) -> c_int
  #[no_mangle]
  pub unsafe extern "C" fn dlopen(filename: *const c_char, flags: c_int) -> *mut c_void {
  - let filename_cstr = CStr::from_ptr(filename);
  - let filename_str = str::from_utf8_unchecked(filename_cstr.to_bytes());
  - eprintln!("dlopen({}, {:#>04X})", filename_str, flags);
  + let filename_opt = if filename.is_null() {
  + None
  + } else {
  + Some(str::from_utf8_unchecked(CStr::from_ptr(filename).to_bytes()))
  + };
  +
  + eprintln!("dlopen({:?}, {:#>04x})", filename_opt, flags);
  +
  + if let Some(filename) = filename_opt {
  + ERROR.store(ERROR_NOT_SUPPORTED.as_ptr() as usize, Ordering::SeqCst);
  ptr::null_mut()
  + } else {
  + 1 as *mut c_void
  + }
  }
  #[no_mangle]
  -pub extern "C" fn dlsym(handle: *mut c_void, symbol: *const c_char) -> *mut c_void {
  +pub unsafe extern "C" fn dlsym(handle: *mut c_void, symbol: *const c_char) -> *mut c_void {
  + let symbol_opt = if symbol.is_null() {
  + None
  + } else {
  + Some(str::from_utf8_unchecked(CStr::from_ptr(symbol).to_bytes()))
  + };
  +
  + eprintln!("dlsym({:p}, {:?})", handle, symbol_opt);
  +
  ptr::null_mut()
  }
  @@ -47,5 +71,5 @@ pub extern "C" fn dlclose(handle: *mut c_void) -> c_int {
  #[no_mangle]
  pub extern "C" fn dlerror() -> *mut c_char {
  - ptr::null_mut()
  + ERROR.swap(0, Ordering::SeqCst) as *mut c_char
  }
  