Author Archives: admin

SQLite tree structures and queries to get sub-trees

SQLite is wonderful! Just today I found that SQLite support queries with a recurse to get the inner sub-trees: CREATE TABLE els ( id INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL UNIQUE ,pid INTEGER DEFAULT NULL REFERENCES els ,name TEXT ); INSERT INTO els (id, pid, name) VALUES (1, NULL, 'top'); INSERT INTO els (id, pid, […]
Posted in Blog, Ideas, Misc, Research, SQLite | Leave a comment

Ru: Archive: Шифруемся в Qt (2013)

Так как оказалось, что наши коммуникации довольно легко просматриваются товарищами из АНБ то похоже что нужно шифровать все коммуникации. Я решил проверить насколько сложно подключить шифрование в разработке Qt приложений. Как оказалось что все совсем несложно даже в случае использовании PGP. Так что тут больше дело привычки разработчика чтобы шифровать критические данные. Вот и попробуем
Posted in Blog, C++, Cryptography, Qt, Ru, Tutorial | Leave a comment

Inferno-rpi-0.6 release

Releasing Inferno-rpi-0.6 Changes: * Added devi2c * Added devspi * Added devgpio (GPIO) * Minor changes/adjustements * Boot to kernel-nogui.bin by default. Change config.txt or enter ; wm/wm Download: * https://bitbucket.org/infpi/inferno-rpi/downloads/inferno-rpi-0.6.zip Installation: 1. Download latest zip package from https://bitbucket.org/infpi/inferno-rpi/downloads 2. Pepare SD card with first DOS partition with size less than 250 MB (vfat32 support […]
Posted in Blog, Inferno OS, Projects, Raspberry Pi, Release | 4 Comments

Inferno-rpi-0.5 release

Releasing Inferno-rpi-0.5 Changes: * Fixed wrong calculatons of memory pool sizes. * Support of Pi-1 models with 512MB RAM. * Update of sources from 9pi project: usbdwc, emmc, etherusb. * Added uartmini module from 9pi. * Use Mntgen by default for /n, /n/local, /n/remote * Boot to kernel-nogui.bin by default. Change config.txt or enter ; […]
Posted in Blog, Inferno OS, Projects, Raspberry Pi, Release | 2 Comments

Wrong size of memory pools – dumb

Occasionally I had a look at /dev/memory: What I saw there? ; cat /dev/memory 2282656 14018478 2314496 14149 6246 18 11735810 main 492768 7009239 499488 110133 106946 4 6516459 heap 4960 14018478 4960 8 1 1 14013506 image ; What? I run my Inferno just on 14+7+14 = 33MB memory? (yep and it still runs […]
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Thinking about user interfaces, part 2

Part 1 Now have a look at existing command line interface: What really human see on the screen? A specialist would say that from bottom (from input/cursor) to up the human sees a story of computer operations. My correction would be that human sees a story of his mental activities shown on the screen. These […]
Posted in Blog, Ideas, Inferno OS, Research | 1 Comment

Inferno-rpi-0.4 release

Releasing Inferno-rpi-0.4 Changes: * Significant performance improvement due to fixed error in process scheduling/idle * Boot time is about ONE second :) Download: * https://bitbucket.org/infpi/inferno-rpi/downloads/inferno-rpi-0.4.zip Installation: 1. Download latest zip package from https://bitbucket.org/infpi/inferno-rpi/downloads 2. Pepare SD card with first DOS partition with size less than 250 MB (vfat32 support is not complete) 3. Unzip all […]
Posted in Blog, Inferno OS, Raspberry Pi, Release | 1 Comment

Inferno-Rpi: project moved

Due to the closure of google code, the project is now moved to: https://bitbucket.org/infpi/inferno-rpi Also added some minor changes and merged with latest inferno-os codebase changes. So returning a little to the project activity and think to keep the project based on dos partition which will be very simple for demo purposes. Also think to […]
Posted in Blog, Embedding, Inferno OS, Raspberry Pi | Leave a comment

Inferno-Rpi boot from dos partition

Just to simplify installation I decided to put all needed files onto fat partition and bind them in init script. So everything is much simple as all your files are on fat partition and easy accessible if you put SD into another computer to copy move etc files. No need to play with partitions and […]
Posted in Blog, Inferno OS, Raspberry Pi, Release | 2 Comments

Inferno raspberry pi image – beta release (beta1)

We are happy to announce the beta release of native port of Inferno OS to Raspberry Pi. There are some important points reached for this stage: 1. Mouse driver 2. Working wm/wm 3. Default memory split 240/16 4. A lot of small fixes and polishing Download Link (~23MB) Repository: http://code.google.com/p/inferno-rpi/
Posted in Blog, Inferno OS, Raspberry Pi, Release, Research | 10 Comments

Inferno raspberry pi image – alpha release (alpha1)

So, we reached the point when we are able to package some small distribution. It can: 1. Boot Kernel 2. Mount file system (kfs) 3. Init Usb subsystem 4. Load Keyboard driver (usb) 5. Load Ethernet driver (usb) 6. Initialize Net subsystem, obtain IP via DHCP 7. Start ndb/cs 8. Launch shell – console It […]
Posted in Blog, Inferno OS, Misc, Projects, Raspberry Pi, Release, Research | 2 Comments

Lab 26, floating point

In Lab 19 we found a problem that kernel raises exception “Undefined instruction” and stops working. It happens on running JIT arm codes produced by Dis. Now it is time to have little review. In Lab 19 I just added sources used in 9pi for handling floating point exceptions but commented real call fpemu() – […]
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Lab 25, network, part 2

After the Lab 24 when we prepared the layout I took serious study of the ways to implement the ethernet driver. And I found that there is actual convergence of 2 ways of implementation that I saw in previous lab. Comparing to implementation of ethernet driver in C (ether.c, smsc.c) it is enough to have […]
Posted in Blog, Inferno OS, Projects, Raspberry Pi, Research, Usb | 3 Comments

Lab 24, network, part 1

This lab will be short; we will add all network modules needed for network layout and make a roadmap how to make the Raspberry Pi ethernet driver. First have a look at other ports and inferno and find what is needed to compile with network support.
Posted in Blog, Inferno OS, Raspberry Pi, Research | 1 Comment

Jongling models beetween threads

We know that in Qt the models are not thread-safe – they totally depend on your implementation. So what we may do to bypass model between threads? Guess that we have some models which implementation we can not adjust much or can not make thread-safe. Danger is that if some model is used somewhere (pointer […]
Posted in Blog, Boost, C++, Models, Qt | 3 Comments

Lab 23, hard disk or SD card

Before this Lab, the only way to bypass information to our Raspberry Pi machine, was the TFTP which downloads kernel from development machine (used Mac). Because kernel also includes root filesystem, we can embed some files there to have minimal read-only filesystem which allows to run dis files and do some testing, like experimenting with […]
Posted in Blog, Inferno OS, Raspberry Pi, Research | 2 Comments

Small news about Inferno-Rpi Labs

Just small update: To keep track of codebase of the Inferno OS on Raspberry Pi Labs we created the google code project to keep the repository and do other stuff related to the labs managements: https://code.google.com/p/inferno-rpi/ All Labs-Commits: https://code.google.com/p/inferno-rpi/source/list
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Qt and use of Cryptography – simple!

In the light of latest news (Snowden et all) it is very clear that all developers should really take care of safety of all communications that your application could perform. In the world of desktop application developments it is often is decided to be postponed and just use plain text protocols or so and later […]
Posted in Blog, C++, Cryptography, Qt, Research | 7 Comments

Designing tree-like models

We found that developers are often confused about implementing tree-like models using Qt classes. Now we can show some tricks and considerations about the way of designing them. First for some refreshment, let’s remind what you have for addressing the elements in the model. This is QModelIndex, which have pointer to model that created the […]
Posted in Blog, C++, Models, Qt, Research | 2 Comments

Overhead cost of using Qt models

I decided to run very simple test to have glance on performance of Qt models and overhead cost of using them. Something very simple as make 1M random strings with random size (note: rnd_str(int) return some random string with specified size)
Posted in Blog, C++, Models, Qt, Research | 3 Comments