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  Smuggling data in pointers

While reading up on The ABA Problem I came across a fantastic hack.  The ABA problem, in a nutshell, results from the inability to atomically access both a pointer and a "marked" bit at the same time (read the wikipedia page).  One fun, but very hackish solution is to "smuggle" data in a pointer.  Example:#include "stdio.h"void * smuggle(void * ptr, int value){  return (void *)( (long long)ptr | (value & 3) );}int recoverData(void * ptr){  return (long long)ptr &...

   C,Pointer,Bit,Data,Atomic,Smuggle     2011-11-14 08:15:59

  Generate certificate in Java -- Store certificate in KeyStore

In previous post, we have explained how to create a certificate chain in Java. After generating the chain, we need to store it somewhere so that it can be used later when we are doing the actual SSL communication, either in a key store or trust store. This post will show you how to store the private key and its associated certificate chain in a keystore file. There are different types of keystore in Java, in this post, we will choose the JKS to demonstrate how to store the certificate chain. Whe...

   Java,Certificate chain,Keystore     2014-08-20 03:56:39

  The Wasteful Legacy of Programming as Language

A few years ago I visited a friend who is a graduate student in linguistics. After some time he asked me if I was aware of the work by Chomsky on formal languages. I told him that yes, Chomsky work was a basis for much of the developments in theoretical computer science. More than that, I was glad to learn that there was something technical that I could share and discuss with other people in linguistics. At the time I found this was just a great coincidence. It was only recently, though, t...

   Programming language,Human language,Chomsky     2011-11-28 10:36:34

  socket_create() from command prompt with WAMP

Problem:I’m working on a wamp system, and have started playing around with sockets. I enabled sockets via the wamp interface:wamp : PHP settings : PHP extensions : php_socketsand could run my php file via my browser.When trying to run the same file via the command prompt (start : run : cmd), I got the following error:Fatal error: Call to undefined function socket_create() in … on line …Solution:The command prompt uses a different php.ini file to the apache server.The Apac...

   PHP,WAMP,Windows,Command line,Socket     2011-05-30 10:59:14

  Supervisord, God and Monit, which one to choose?

With the popularity of Docker, more and more service have been moved into docker containers and they are easy to build up and maintain for each atomic service(though it's a bit complex to maintain multiple docker containers which contain different service to form a complete solution). Ideally, each docker container should only contain one service which has only one running process. However, in reality there would be cases multiple processes would run in one single docker container and there is a...

   DEVOPS,MONIT,SUPERVISORD,GOD,DOCKER     2017-11-25 12:28:11

  Node.js: Five Things Every PHP Developer Should Know

I recently started working on a few Node.js applications. Coming most recently from PHP (and Drupal in particular), I found the transition to Node.js to be surprisingly easy. Pleasurable, in fact. But I had to learn to think differently about a few things. Below I list the five things I think every PHP developer should know about Node.js. 1. Node.js Is Built On Chrome's JavaScript Engine Google's browser, Chrome, has a notoriously fast JavaScript engine called V8. And this JavaScript engine ...

   PHP,Node.js,Developer,Feature     2012-02-09 07:37:48

  Why does Symbian collapse?

On 24th January, Nokia announces a disappointing news that they would give up Symbian. The 808 PureView released last year will be its last Symbian model.  Symbian was born in 1998, it was supported by the then three mobile giants : Sony Ericson, Motorola and Nokia after its birth, later Samsung and LG also joined the Symbian camp. In 2000, the first Symbian model in the world Ericoson R380 was released, in 20006, there were over 100 million Symbian handphones on the market. But in 2007, t...

   Nokia, Symbian, Collapse, Analysis     2013-01-28 03:06:09

  Why is Great Design so Hard?

I want to take a slight detour from usable privacy and security and discuss issues of design. I was recently at the Microsoft Faculty Summit, an annual event where Microsoft discusses some of the big issues and directions they are headed. In one of the talks, a designer at Microsoft mentioned two data points I've informally heard before but had never confirmed. First, the ratio of developers to user interface designers at Microsoft was 50:1. Second, this ratio was better than any other comp...

   Apple,Microsoft,UI design     2011-03-28 02:06:31

  Permutation implementation in Java

Permutation is a very basic and important mathematic concept we learned in school. It has very practical applications in real world. For example, in football. In simple, permutation describes all possible ways of doing something. For example, there are six permutations of the set {1,2,3}, namely: (1,2,3), (1,3,2), (2,1,3), (2,3,1), (3,1,2), and (3,2,1). In general, for n items, there are n! number of permutations to arrange these items. How can we implement this algorithm in programming programm...

   Permutation,Implementation,Java,Sample     2015-03-26 02:18:14

  Sundar Pichai : Excited to try out iOS 7

Google Android business executives Sundar Pichai said on Twitter that he was excited to try out iOS7 beta and he would like to register as a Apple developer in order to experience iOS 7 early.The real reason why Sundar Pichai expresses interest on iOS 7 is not yet known, but at least "Know thyself, ever-victorious" is correct. Because as a person who is in charge of Android, he should grasp the status of competitors in order to know what the Android system can improve.However, Apple's iOS 7 appl...

   iOS 7,Google,Sundar Pichai     2013-06-12 00:57:30