rust/src/libstd/sys.rs

297 lines
7.9 KiB
Rust

// Copyright 2012 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.
//! Misc low level stuff
#[allow(missing_doc)];
use c_str::ToCStr;
use cast;
#[cfg(stage0)]
use io;
use libc;
use libc::{c_char, size_t};
use repr;
use str;
use unstable::intrinsics;
/// Returns the size of a type
#[inline]
pub fn size_of<T>() -> uint {
unsafe { intrinsics::size_of::<T>() }
}
/// Returns the size of the type that `_val` points to
#[inline]
pub fn size_of_val<T>(_val: &T) -> uint {
size_of::<T>()
}
/**
* Returns the size of a type, or 1 if the actual size is zero.
*
* Useful for building structures containing variable-length arrays.
*/
#[inline]
pub fn nonzero_size_of<T>() -> uint {
let s = size_of::<T>();
if s == 0 { 1 } else { s }
}
/// Returns the size of the type of the value that `_val` points to
#[inline]
pub fn nonzero_size_of_val<T>(_val: &T) -> uint {
nonzero_size_of::<T>()
}
/**
* Returns the ABI-required minimum alignment of a type
*
* This is the alignment used for struct fields. It may be smaller
* than the preferred alignment.
*/
#[inline]
pub fn min_align_of<T>() -> uint {
unsafe { intrinsics::min_align_of::<T>() }
}
/// Returns the ABI-required minimum alignment of the type of the value that
/// `_val` points to
#[inline]
pub fn min_align_of_val<T>(_val: &T) -> uint {
min_align_of::<T>()
}
/// Returns the preferred alignment of a type
#[inline]
pub fn pref_align_of<T>() -> uint {
unsafe { intrinsics::pref_align_of::<T>() }
}
/// Returns the preferred alignment of the type of the value that
/// `_val` points to
#[inline]
pub fn pref_align_of_val<T>(_val: &T) -> uint {
pref_align_of::<T>()
}
/// Returns the refcount of a shared box (as just before calling this)
#[inline]
pub fn refcount<T>(t: @T) -> uint {
unsafe {
let ref_ptr: *uint = cast::transmute_copy(&t);
*ref_ptr - 1
}
}
#[cfg(not(stage0))]
pub fn log_str<T>(t: &T) -> ~str {
use rt::io;
use rt::io::Decorator;
let mut result = io::mem::MemWriter::new();
repr::write_repr(&mut result as &mut io::Writer, t);
str::from_utf8_owned(result.inner())
}
#[cfg(stage0)]
pub fn log_str<T>(t: &T) -> ~str {
do io::with_str_writer |w| {
repr::write_repr(w, t)
}
}
/// Trait for initiating task failure.
pub trait FailWithCause {
/// Fail the current task, taking ownership of `cause`
fn fail_with(cause: Self, file: &'static str, line: uint) -> !;
}
impl FailWithCause for ~str {
fn fail_with(cause: ~str, file: &'static str, line: uint) -> ! {
do cause.with_c_str |msg_buf| {
do file.with_c_str |file_buf| {
begin_unwind_(msg_buf, file_buf, line as libc::size_t)
}
}
}
}
impl FailWithCause for &'static str {
fn fail_with(cause: &'static str, file: &'static str, line: uint) -> ! {
do cause.with_c_str |msg_buf| {
do file.with_c_str |file_buf| {
begin_unwind_(msg_buf, file_buf, line as libc::size_t)
}
}
}
}
// FIXME #4427: Temporary until rt::rt_fail_ goes away
pub fn begin_unwind_(msg: *c_char, file: *c_char, line: size_t) -> ! {
use either::Left;
use option::{Some, None};
use rt::in_green_task_context;
use rt::task::Task;
use rt::local::Local;
use rt::logging::Logger;
use str::Str;
unsafe {
// XXX: Bad re-allocations. fail! needs some refactoring
let msg = str::raw::from_c_str(msg);
let file = str::raw::from_c_str(file);
// XXX: Logging doesn't work correctly in non-task context because it
// invokes the local heap
if in_green_task_context() {
// XXX: Logging doesn't work here - the check to call the log
// function never passes - so calling the log function directly.
do Local::borrow |task: &mut Task| {
let msg = match task.name {
Some(ref name) =>
fmt!("task '%s' failed at '%s', %s:%i",
name.as_slice(), msg, file, line as int),
None =>
fmt!("task <unnamed> failed at '%s', %s:%i",
msg, file, line as int)
};
task.logger.log(Left(msg));
}
} else {
rterrln!("failed in non-task context at '%s', %s:%i",
msg, file, line as int);
}
let task: *mut Task = Local::unsafe_borrow();
if (*task).unwinder.unwinding {
rtabort!("unwinding again");
}
(*task).unwinder.begin_unwind();
}
}
#[cfg(test)]
mod tests {
use cast;
use sys::*;
#[test]
fn size_of_basic() {
assert_eq!(size_of::<u8>(), 1u);
assert_eq!(size_of::<u16>(), 2u);
assert_eq!(size_of::<u32>(), 4u);
assert_eq!(size_of::<u64>(), 8u);
}
#[test]
#[cfg(target_arch = "x86")]
#[cfg(target_arch = "arm")]
#[cfg(target_arch = "mips")]
fn size_of_32() {
assert_eq!(size_of::<uint>(), 4u);
assert_eq!(size_of::<*uint>(), 4u);
}
#[test]
#[cfg(target_arch = "x86_64")]
fn size_of_64() {
assert_eq!(size_of::<uint>(), 8u);
assert_eq!(size_of::<*uint>(), 8u);
}
#[test]
fn size_of_val_basic() {
assert_eq!(size_of_val(&1u8), 1);
assert_eq!(size_of_val(&1u16), 2);
assert_eq!(size_of_val(&1u32), 4);
assert_eq!(size_of_val(&1u64), 8);
}
#[test]
fn nonzero_size_of_basic() {
type Z = [i8, ..0];
assert_eq!(size_of::<Z>(), 0u);
assert_eq!(nonzero_size_of::<Z>(), 1u);
assert_eq!(nonzero_size_of::<uint>(), size_of::<uint>());
}
#[test]
fn nonzero_size_of_val_basic() {
let z = [0u8, ..0];
assert_eq!(size_of_val(&z), 0u);
assert_eq!(nonzero_size_of_val(&z), 1u);
assert_eq!(nonzero_size_of_val(&1u), size_of_val(&1u));
}
#[test]
fn align_of_basic() {
assert_eq!(pref_align_of::<u8>(), 1u);
assert_eq!(pref_align_of::<u16>(), 2u);
assert_eq!(pref_align_of::<u32>(), 4u);
}
#[test]
#[cfg(target_arch = "x86")]
#[cfg(target_arch = "arm")]
#[cfg(target_arch = "mips")]
fn align_of_32() {
assert_eq!(pref_align_of::<uint>(), 4u);
assert_eq!(pref_align_of::<*uint>(), 4u);
}
#[test]
#[cfg(target_arch = "x86_64")]
fn align_of_64() {
assert_eq!(pref_align_of::<uint>(), 8u);
assert_eq!(pref_align_of::<*uint>(), 8u);
}
#[test]
fn align_of_val_basic() {
assert_eq!(pref_align_of_val(&1u8), 1u);
assert_eq!(pref_align_of_val(&1u16), 2u);
assert_eq!(pref_align_of_val(&1u32), 4u);
}
#[test]
fn synthesize_closure() {
use unstable::raw::Closure;
unsafe {
let x = 10;
let f: &fn(int) -> int = |y| x + y;
assert_eq!(f(20), 30);
let original_closure: Closure = cast::transmute(f);
let actual_function_pointer = original_closure.code;
let environment = original_closure.env;
let new_closure = Closure {
code: actual_function_pointer,
env: environment
};
let new_f: &fn(int) -> int = cast::transmute(new_closure);
assert_eq!(new_f(20), 30);
}
}
#[test]
#[should_fail]
fn fail_static() { FailWithCause::fail_with("cause", file!(), line!()) }
#[test]
#[should_fail]
fn fail_owned() { FailWithCause::fail_with(~"cause", file!(), line!()) }
}