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// 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.
use libc::c_void;
#[cfg(unix)]
use libc::c_int;
#[cfg(unix)]
use ptr::null;
#[cfg(windows)]
use libc::types::os::arch::extra::{DWORD, LPVOID, BOOL};
#[cfg(unix)]
pub type Key = pthread_key_t;
#[cfg(unix)]
#[fixed_stack_segment]
#[inline(never)]
pub unsafe fn create(key: &mut Key) {
assert_eq!(0, pthread_key_create(key, null()));
}
#[cfg(unix)]
pub unsafe fn set(key: Key, value: *mut c_void) {
assert_eq!(0, pthread_setspecific(key, value));
}
#[cfg(unix)]
pub unsafe fn get(key: Key) -> *mut c_void {
pthread_getspecific(key)
}
#[cfg(target_os="macos")]
#[allow(non_camel_case_types)] // foreign type
type pthread_key_t = ::libc::c_ulong;
#[cfg(target_os="linux")]
#[cfg(target_os="freebsd")]
#[cfg(target_os="android")]
#[allow(non_camel_case_types)] // foreign type
type pthread_key_t = ::libc::c_uint;
#[cfg(unix)]
extern {
fn pthread_key_create(key: *mut pthread_key_t, dtor: *u8) -> c_int;
// This function is a very cheap operation on both osx and unix. On osx, it
// turns out it's just three instructions, and on unix it's a cheap function
// which only uses a very small amount of stack.
//
// This is not marked as such because we think it has a small stack, but
// rather we would like to be able to fetch information from
// thread-local-storage when a task is running very low on its stack budget.
// For example, this is invoked whenever stack overflow is detected, and we
// obviously have very little budget to deal with (certainly not anything
// close to a fixed_stack_segment)
#[rust_stack]
fn pthread_getspecific(key: pthread_key_t) -> *mut c_void;
#[rust_stack]
fn pthread_setspecific(key: pthread_key_t, value: *mut c_void) -> c_int;
}
#[cfg(windows)]
pub type Key = DWORD;
#[cfg(windows)]
#[fixed_stack_segment]
#[inline(never)]
pub unsafe fn create(key: &mut Key) {
static TLS_OUT_OF_INDEXES: DWORD = 0xFFFFFFFF;
*key = TlsAlloc();
assert!(*key != TLS_OUT_OF_INDEXES);
}
#[cfg(windows)]
pub unsafe fn set(key: Key, value: *mut c_void) {
assert!(0 != TlsSetValue(key, value))
}
#[cfg(windows)]
pub unsafe fn get(key: Key) -> *mut c_void {
TlsGetValue(key)
}
#[cfg(windows, target_arch = "x86")]
extern "stdcall" {
fn TlsAlloc() -> DWORD;
// See the reasoning in pthread_getspecific as to why this has the
// 'rust_stack' attribute, as this function was also verified to only
// require a small amount of stack.
#[rust_stack]
fn TlsGetValue(dwTlsIndex: DWORD) -> LPVOID;
#[rust_stack]
fn TlsSetValue(dwTlsIndex: DWORD, lpTlsvalue: LPVOID) -> BOOL;
}
#[cfg(windows, target_arch = "x86_64")]
extern {
fn TlsAlloc() -> DWORD;
// See above.
#[rust_stack]
fn TlsGetValue(dwTlsIndex: DWORD) -> LPVOID;
#[rust_stack]
fn TlsSetValue(dwTlsIndex: DWORD, lpTlsvalue: LPVOID) -> BOOL;
}
#[test]
fn tls_smoke_test() {
use cast::transmute;
unsafe {
let mut key = 0;
let value = ~20;
create(&mut key);
set(key, transmute(value));
let value: ~int = transmute(get(key));
assert_eq!(value, ~20);
let value = ~30;
set(key, transmute(value));
let value: ~int = transmute(get(key));
assert_eq!(value, ~30);
}
}
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