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Henning Ottesen henninglive

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  • Mo i Rana, Norway
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@henninglive
henninglive / isqrt.rs
Created April 21, 2018 18:07
Integer Square Root
/// Integer Square Root
///
/// `n` is the positive integer for which the return value is the greatest
/// integer less than or equal to the square root of n.
pub fn isqrt(mut n: usize) -> usize {
let mut res = 0;
let mut b = 1 << ((::std::mem::size_of::<usize>() * 8) - 2);
while b > n {
b >>= 2
@henninglive
henninglive / sum_of_range.rs
Created March 22, 2018 22:24
Calculate sum of range with step in constant time
use std::ops::Range;
fn sum_range2(range: Range<usize>, step: usize) -> usize {
assert!(range.start < range.end && step > 0);
let mut start = range.start;
while start % step != 0 {
start += 1;
}
@henninglive
henninglive / fold_dyn_dispatch.rs
Created March 22, 2018 03:40
Example showing how to fold a list with different types using dynamic dispatch.
#[macro_use]
extern crate mopa;
use std::any::TypeId;
use std::fmt::Debug;
// Add std::any::Any methods to Object.
mopafy!(Object);
trait Object: mopa::Any + Debug {
@henninglive
henninglive / all_splits.rs
Created September 27, 2017 16:10
All possible ways to slice a slice
fn all_splits<T>(s: &[T]) -> Vec<Vec<&[T]>> {
let len = s.len();
let mut vv = Vec::with_capacity(1<<(len - 1));
for mask in 0usize..(1<<(len - 1)) {
let mut v = Vec::with_capacity(mask.count_ones() as usize + 1);
let mut prev = 0;
for i in 1..len {
if (mask >> (i - 1)) & 0b1 != 0 {
v.push(&s[prev..i]);
prev = i;
@henninglive
henninglive / lib.diff
Last active August 29, 2017 19:03
Diff of https://github.com/brayniac/mpmc/blob/master/src/lib.rs
Diff of https://github.com/brayniac/mpmc/blob/master/src/lib.rs
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -102,7 +102,7 @@ impl<T: Send> State<T> {
let mask = self.mask;
let mut pos = self.enqueue_pos.load(Relaxed);
loop {
- let node = &self.buffer[pos & mask];
+ let node = unsafe { self.buffer.get_unchecked(pos & mask) };
@henninglive
henninglive / command.rs
Created June 18, 2017 20:05
Command Pattern
trait Command<T> {
type Err;
fn forward(&mut self, receiver: &mut T) -> Result<(), Self::Err>;
fn backwards(&mut self, receiver: &mut T) -> Result<(), Self::Err>;
}
struct CommandStack<T, C: Command<T>>{
stack: Vec<C>,
receiver: T,
}
@henninglive
henninglive / nix_test_1.txt
Created June 2, 2017 20:52
nix test failures
Running target/debug/deps/test-6852390ff37b5910
running 73 tests
WARNING: dropped an in-progress AioCbtest sys::test_aio::test_lio_listio_read_immutable ... ok
test sys::test_aio::test_aio_suspend ... ok
test sys::test_aio::test_drop ... ok
test sys::test_aio::test_lio_listio_wait ... ok
test sys::test_aio::test_read_immutable_buffer ... ok
test sys::test_aio::test_cancel ... ok
test sys::test_aio::test_aio_cancel_all ... ok
@henninglive
henninglive / nix_stacktrace.txt
Last active June 1, 2017 00:27
thread 'main' panicked at 'write failed: Value too large for defined data type (os error 75)', test/test_mount.rs:53
stack backtrace:
0: std::sys::imp::backtrace::tracing::imp::unwind_backtrace
at /checkout/src/libstd/sys/unix/backtrace/tracing/gcc_s.rs:49
1: std::sys_common::backtrace::_print
at /checkout/src/libstd/sys_common/backtrace.rs:71
2: std::panicking::default_hook::{{closure}}
at /checkout/src/libstd/sys_common/backtrace.rs:60
at /checkout/src/libstd/panicking.rs:355
3: std::panicking::default_hook
@henninglive
henninglive / Cargo.toml
Last active December 19, 2019 23:10
[package]
name = "load-library-test"
version = "0.1.0"
authors = ["Henning Ottesen <henning@live.no>"]
[dependencies]
winapi = "0.2"
kernel32-sys = "0.2.2"
@henninglive
henninglive / any_collection.rs
Created May 24, 2017 15:50
use std::any::{Any, TypeId};
use std::collections::BTreeMap;
trait AnySlice {
fn as_any_mut(&mut self) -> &mut Any;
fn any_get(&self, index: usize) -> Option<&Any>;
fn any_len(&self) -> usize;
}
struct AnyCollection(BTreeMap<TypeId, Box<AnySlice>>);