Linux on Mamadou Babaei

Building Unreal Engine 5.6 From the GitHub Source Code on GNU/Linux With Android Support

Sun, 08 Jun 2025 10:07:00 +0200

Building Unreal Engine 5.6 from the GitHub Source Code With Android Support

Alright, I’m back with another video.

If you caught the last one on building Unreal Engine 5.6 from source on Windows, you already know the drill. As promised—this is the GNU/Linux edition.

We’re doing it the Linux way this time: clean, efficient, and just a bit different. Let’s dive in.

UPDATE [2025/07/04]: The original NDK_ROOT and NDKROOT environment variables values used during the video shoot were misconfigured. That has now been corrected.

Building Unreal Engine 5.6 From the GitHub Source Code on Microsoft Windows

Mon, 05 May 2025 23:00:00 +0200

Building Unreal Engine 5.6 from the GitHub Source Code

Alright… I’m back. Yes, I know—I vanished for a while. But just like the upcoming Unreal Engine 5.6 release, I’ve been quietly cooking in the shadows. And now… we’re both making a comeback.

Today’s tutorial is all about how to build Unreal Engine 5.6 from source—on Windows. That’s right, 5.6 isn’t officially out yet, but we’re not waiting around. If you’re impatient like me—or just curious to see what Epic’s brewing before the rest of the world—this video is for you.

Now, some of you patient folks out there might be thinking: “Why bother? Can’t I just wait for the release?” Fair question. But here’s the deal—I work for a company that publishes Unreal Engine plugins on the Fab Store. And they want their plugin ready on day zero when the new engine drops. The catch? Epic only allows you to submit plugins once the final version is officially released. So to stay ahead of the curve, we grab the source early, build it, test it, and make sure everything works before the launch day.

And hey, if you’re a Linux user—don’t worry—I’ve got a separate video coming soon. Just not today. Because building on Linux is like dating in your forties… not complicated, exactly—just different.

We’ll be diving into more Unreal Engine 5.6 goodness over the coming months, so buckle up, hit that subscribe button, and let’s get nerdy.

WebRTC IP Leak Demonstration

Mon, 25 Nov 2024 00:49:00 +0100

WebRTC IP Leak Demonstration using Rust and JavaScript

Deep in the vast jungle of the internet, an elusive predator lies in wait: the WebRTC IP leak. This invisible hunter slithers through the dense digital undergrowth, silent and unseen, ready to strike its next target. The IP addresses of its unsuspecting victims are exposed in an instant. But its danger isn’t merely technical; if you’re a political activist in a repressive regime, leaking your IP could jeopardize your very life. Today, we embark on an expedition to track this hidden predator, uncover its secrets, and learn how to protect ourselves before it strikes.

How to disable HP Proliant ML350p Gen8 P420i RAID controller, enable HBA mode (a.k.a. pass-through), and perform a FreeBSD root on ZFS installation

Wed, 10 Nov 2021 18:33:00 +0100

I recently purchased a second-hand HP Proliant ML350p Gen8 in order to be used as a home server and to my disappointment realized I won’t be able to disable the hardware RAID that comes with this model, at least at first glance. Well, there is a way to do that, which is supported by HP themselves. And, this is how to do it the easy way!

But, before we proceed any further, you might ask why do I need to disable the hardware RAID? The answer is because I need to install ZFS. There is already plenty of documentation why installing ZFS on a hardware RAID is a terrible idea. Thus, I won’t go over that since it’s not the focus of this article.

Again, before we go any further there’s a catch you should know about. If you’d enable HBA-mode, the server won’t be able to boot from any disk connected in HBA mode to the controller! You should consider this before converting to HBA mode. In case you need to perform a FreeBSD/Linux root on ZFS installation through this controller there are two solutions:

1. Installing in hardware RAID mode, but making each disk a RAID-0 array consisting of only one disk. For example, if you’ve got 8 disks, you’ll end up with 8 RAID-0 arrays. Then you’d perform a ZFS installation and your operating system boots as expected. Though this is not recommended and if you’d proceed with this approach, it renders the rest of this post useless.

2. HP Proliant ML350p provides an SD-Card slot, which can be used to install a full system, which is not recommended due to the wear and tear effect of SDCards with each write-operation on them. In addition to that, this storage type is costly and slow. For example, a SanDisk SDXC Extreme Pro 256GB, which provides a write speed of 90MB/s and read speed of 170MB/s, costs around €99,99 where I live. With today’s standards, this is not fast at all or even good enough, especially on a server. I was also able to find a Sandisk CF Express Extreme Pro 512GB type B, with a write speed of 800MB/s and a read speed of 1500MB/s. It only costs €629,-, which costs an arm and leg to buy!

So, then! What’s the solution one might ask? We are going to install only /boot partition on the internal SD Card. Note, that placing only a bootloader such as GRUB, rEFInd or other similar tools won’t work as they won’t be able to see the boot drive anyway! So, the only solution is to put the boot partition on the SDCard. This way, the system only reads it one time at boot and it does not even have to be an expensive SD-Card.

So, let’s begin!

A quick workaround for Unreal Engine Modeling Tools Editor Mode plugin not showing up on Linux and macOS

Mon, 08 Nov 2021 01:10:00 +0100

UPDATE [2021/11/08]: For whitelisting macOS, one could simply add Mac to PlatformAllowList inside the .uplugin file. e.g.:

Whitelisting Linux inside ModelingToolsEditorMode.uplugin

	"Modules": [
		{
			"Name": "ModelingToolsEditorMode",
			"Type": "Editor",
			"LoadingPhase": "Default",
			"PlatformAllowList": [ "Win64", "Linux", "Mac" ]
		}
	],

I’ve been trying to enable and make use of UE5’s Modeling Tools Editor Mode Plugin inside the editor built from ue5-main and 5.0 and struggled to some extent. According to Epic Games, this should suffice:

If you are starting up a new project, the modeling mode plugin may need to be turned on. From the Plugins window, enable the Modeling Tools Editor Mode Plugin and restart Unreal Engine.

Russell Paul from Unreal Engine's blog Unreal Engine 5’s modeling mode takes shape

So, I did enable the plugin from inside the editor:

Enabling Unreal Engine Modeling Tools Editor Mode Plugin

To no avail and I was never able to find it inside the UE5 editor:

Unreal Engine Modeling Tools Editor Mode plugin not showing up after being enabled

Despite that, I was able to figure out what’s wrong. Here’s how I fixed it on Linux and it’s an easy fix. It probably works on macOS, too. Though I have no idea why Epic Games has disabled it on non-Windows platforms in spite of the fact that it works just fine.

Host Unreal Engine 4 projects on Microsoft Azure DevOPS with unlimited cost-free Git LFS quota

Sat, 17 Jul 2021 16:12:00 +0200

Host Unreal Engine 4 projects on Microsoft Azure DevOPS with unlimited cost free Git LFS quota

UPDATE 1 [2021/07/25]: It seems that Git LFS is able to resume your pushes after a network failure. At least it’s like that on Microsoft Azure DevOPS. So, it should be totally redundant to divide huge commits into smaller ones. How have I noticed this? Today, I pushed a huge single commit (around 53GBs) and it failed at 39GB due to a connection error without me noticing it for some time. A few hours later, when I made another attempt by issuing the push command again, it picked up and resumed the push at 39GB, which was really exciting.

UPDATE 2 [2021/07/25]: After pushing the repository to Azure DevOPS, if you find your self stuck in git pull without doing anything, the following command will fix the consecutive pulls:

$ git pull origin master

Or, alternatively:

$ git fetch origin master
$ git reset --hard FETCH_HEAD

UPDATE 3 [2021/07/28]: I’ve noticed due to the fact that the files modification times affect how Rsync and Git work by default, my approach in writing the original script was totally wrong, which in turn caused a bug where on each update it committed all tracked files over again causing huge bloat in the repository, despite the fact that the content of the files was unchanged. Thus, it led me to completely rewrite the script. Hopefully, the new script has been extensively tested with two repositories/projects and works as expected. In addition to that, the script now shows progress for every step, which is a nice addition in order to keep you informed and give an estimation of the time it is going to take to get the job done. And, last but not least, I have edited and improved the blog post a bit.

UPDATE 4 [2021/08/04]: Due to nested .gitignore files inside the Unreal Engine dependencies, I noticed tiny bits of dependencies for building UE4/UE5 on Microsoft Windows are not getting copied over to the repository. As a result, I fixed the script in order to also take care of that.

UPDATE 5 [2021/11/30]: Sometimes it’s possible that the amount of renamed Unreal Engine files surpass the Git’s optimal rename limit inside the Sync repository (the intermediary local git repository that we are going to use for syncing the engine source code with upstream):

warning: exhaustive rename detection was skipped due to too many files.
warning: you may want to set your diff.renameLimit variable to at least 13453 and retry the command.

So, you could set that to a really large number in order to keep track of file renames:

$ cd ~/dev/MamadouArchives-Sync
$ git config diff.renameLimit 999999
$ git config merge.renameLimit 999999

Note: You will get this warning only when the Git option diff.renames is set to true (default behavior). Likewise, the above settings does not have any effects when the copy/rename detection is turned off. Nonetheless, you can always check your settings with:

$ git config -l

UPDATE 6 [2021/12/18]: I’ve added a step regarding EngineAssociation in the project’s .uproject file, which I forgot to mention in the original post.

UPDATE 7 [2023/03/03]: In UE5 UE4Games.uprojectdirs file shas been renamed to Default.uprojectdirs. Though the syntax and the contents of the file has remained the same.

UPDATE 8 [2023/03/04]: After upgrading my project to Unreal Engin 5.1 despite the fact that I’ve already set the git configuration http.version to HTTP/1.1 as instructed in this article, despite the commit size of no bigger than 166.30 MB and the acceptable upload bandwidth I’ve got, I was getting HTTP 413 Request Entity Too Large error:

Enumerating objects: 190058, done.
Counting objects: 100% (164439/164439), done.
Delta compression using up to 16 threads
Compressing objects: 100% (113439/113439), done.
Writing objects: 100% (138834/138834), 166.30 MiB | 47.32 MiB/s, done.
Total 138834 (delta 35613), reused 121343 (delta 22206), pack-reused 0
error: RPC failed; HTTP 413 curl 22 The requested URL returned error: 413
send-pack: unexpected disconnect while reading sideband packet
fatal: the remote end hung up unexpectedly
Everything up-to-date

I tried every suggestion that I came across in order to debug and resolve the issue to no avail. Including enabling git verbose logging:

$ export GIT_TRACE_PACKET=1                      
$ export GIT_TRACE=1
$ export GIT_CURL_VERBOSE=1

And then maxing out on all the size limits, buffer, packet sizes, and other hints:

[core]
	compression = 0
    packedGitLimit = 512m
    packedGitWindowSize = 512m
[http]
    postBuffer = 2147483648
[https]
    postBuffer = 2147483648
[init]
    defaultBranch = master
[pack] 
    deltaCacheSize = 2047m
    packSizeLimit = 2047m
	window = 1
    windowMemory = 2047m

Then I tried to change the origin URL to SSH:

[remote "origin"]
	url = https://SOME-ORGANIZATION@dev.azure.com/SOME-ORGANIZATION/MamadouArchives/_git/MamadouArchives
	#url = git@ssh.dev.azure.com:v3/SOME-ORGANIZATION/MamadouArchives/MamadouArchives

And then pushing without LFS:

$ git push --set-upstream origin 5.1 --no-verify

This attempt was futile as well, that made me revert back to https. Then I tried to push commit by commit since I had made a few commits using (5.1 which has been repeated twice in the following command, is the name of the new local branch intended to be pushed):

$ git rev-list --reverse 5.1 | ruby -ne 'i ||= 0; i += 1; puts $_ if i % 1 == 0' | xargs -I{} git push origin +{}:refs/heads/5.1 --no-verify

And sadly, the approach of pushing one commit at a time was frutiless as well :/

Thus, for the time being I’m stuck pushing the updated project from my Linux machine and pulling it from my Windows machine. I’ll do another updated once I’ve figured what’s going wrong.

UPDATE 9 [2023/03/04]: As an experiment, I did create a new organiation and a new repository inside it. Then prior to changing the origin URL, I fetched all LFS objects issuing:

$ git lfs fetch --all
fetch: 78618 objects found, done.                                                                      
fetch: Fetching all references...

Then, I decided to first push the Git comnmits without the LFS objects, so after updating the origin URL inside the .git/config:

$ git push --set-upstream origin 5.1 --no-verify
Enumerating objects: 296578, done.
Counting objects: 100% (296578/296578), done.
Delta compression using up to 16 threads
Compressing objects: 100% (210384/210384), done.
Writing objects: 100% (296578/296578), 360.11 MiB | 5.78 MiB/s, done.
Total 296578 (delta 78143), reused 296578 (delta 78143), pack-reused 0
remote: Analyzing objects... (296578/296578) (77738 ms)
remote: Storing packfile... done (10303 ms)
remote: Storing index... done (3740 ms)
To https://dev.azure.com/SOME-ORGANIZATION/MamadouArchives/_git/MamadouArchives
 * [new branch]            5.1 -> 5.1
branch '5.1' set up to track 'origin/5.1'

¯\_(ツ)/¯ as unexpected as it seems, it worked! As you can see my actual Git objects without the LFS objects on this repository are in no way near the 10 GB size limit:_

$ git count-objects -vH                         
count: 0               
size: 0 bytes
in-pack: 296583
packs: 1
size-pack: 366.76 MiB
prune-packable: 0
garbage: 0
size-garbage: 0 bytes

The issue might be that I’ve reached some kind of limit on the main organization that I’m not aware of.

Anyways, then I pushed the master and checked out back the new brnach for continuation on the upgrade:

$ git checkout master
$ git push origin master --no-verify
$ git checkout 5.1

And, then proceeded to pushing all LFS objects:

$ git lfs push origin --all

UPDATE 10 [2023/03/05]: Yesterday, I removed a large redundant repository from the previous organization, in order to see if I could still push my updates and the error I am getting was not due to hitting some kind of ceiling limit. It didn’t work. I did also cleanup the limit hacks I’ve added to my ~/.gitconfig in UPDATE 8. Then, after successfully pushing to the new organization/repository, I’ve decided to revert back the URL section for the orgin inside my .git/config inside the local repository and try to push once more to the old repository and guess what? It worked! Weird Microsoft/Azure! Not sure what fixed the issue. It could be even I had to wait for Microsoft to clean up the repository’s space I’ve deleted if the organization size limit was the issue. Don’t really know.

Among the gamedev industry, it’s a well-known fact that Unreal Engine projects sizes have always been huge and a pain to manage properly. And it becomes more painful by the day as your project moves forward and grows in size. Some even keep the Engine source and its monstrous binary dependencies inside their source control management software. In case you are a AAA game development company or you are working for one, there’s probably some system in place with an unlimited quota to take care of that. But, for most of us indie devs, or individual hobbyists, it seems there are not lots of affordable options, especially that your team is scattered across the globe.

There are plenty of costly solutions to keep UE4 projects under source control; ranging from maintaining a local physical server or renting a VPS with plenty of space on the cloud, equipped with a self-hosted Git, SVN, or Perforce, to use cloud SCM providers such as GitHub, GitLab, BitBucket, or Perforce. Since I prefer cloud SCM providers and Git + Git LFS (which also supports file locking), let’s take a look at some popular ones such as GitHub and GitLab.

GitHub for one, provides data packs, but the free offering is far from enough for collaborative UE4 projects:

Every account using Git Large File Storage receives 1 GB of free storage and 1 GB a month of free bandwidth. If the bandwidth and storage quotas are not enough, you can choose to purchase an additional quota for Git LFS. Unused bandwidth doesn’t roll over month-to-month.

…

Additional storage and bandwidth is offered in a single data pack. One data pack costs $5 per month, and provides a monthly quota of 50 GB for bandwidth and 50 GB for storage. You can purchase as many data packs as you need. For example, if you need 150 GB of storage, you’d buy three data packs.

github.com About billing for Git Large File Storage

For GitLab, although the initial generous 10GB repository size is way beyond the 1GB repository size offer by GitHub, the LFS pricing is insanely high:

Additional repository storage for a namespace (group or personal) is sold in annual subscriptions of $60 USD/year in increments of 10GB. This storage accounts for the size calculated from Repositories, which includes the git repository itself and any LFS objects.

When adding storage to an existing subscription, you will be charged the prorated amount for the remaining term of your subscription. (ex. If your subscription ends in 6 months and you buy storage, you will be charge for 6 months of the storage subscription, i.e. $30 USD)

gilab.com Licensing and subscription FAQ, About Supplemental Storage

Well, before this all get you disappointed, let’s hear the good news from the Microsoft Azure DevOPS team:

In uncommon circumstances, repositories may be larger than 10GB. For instance, the Windows repository is at least 300GB. For that reason, we do not have a hard block in place. If your repository grows beyond 10GB, consider using Git-LFS, Scalar, or Azure Artifacts to refactor your development artifacts.

microsoft.com Git limits

Before we proceed any further, there are some catches to consider about Microsoft Azure DevOPS:

1. The maximum Git repository size is 10GB, which considering that we keep binary assets and huge files in LFS, is way beyond any project’s actual needs. For Git LFS it seems that Microsoft since at least 2015 has been providing unlimited free storage. For comparison, the engine source code for 4.27 is 1.4GB, which in turn when it’s getting committed to the git repo becomes less than 230MB:

$ cd /path/to/ue4.27/source

$ du -h
1.4G	.

$ git init
$ git add .
$ git commit -m "add unreal engine 4.27 source code"

$ git count-objects -vH

count: 97545
size: 900.25 MiB
in-pack: 110815
packs: 1
size-pack: 227.80 MiB
prune-packable: 97545
garbage: 0
size-garbage: 0 bytes

2. The maximum push size is limited to 5GB at a time. The 5GB limit is only for files in the actual repository and it won’t affect LFS objects. Thus, there are no limits for LFS objects’ pushes. Despite that, if your internet connection is not stable, you could divide your files into multiple commits and push them separately. For example, the initial git dependencies for UE 4.27 is around 40GB spanned across ~70,000 files. Instead of committing and pushing a 40GB chunk all at once, one could divide that into multiple commits and push those commits one by one using the following command:

$ git rev-list --reverse master \
    | ruby -ne 'i ||= 0; i += 1; puts $_ if i % 1 == 0' \
    | xargs -I{} git push origin +{}:refs/heads/master

3. Sadly, at the moment Azure DevOPS does not support LFS over SSH. So, you are bound to git push/pull over https, which for some might be annoying. Especially, that it keeps asking for the https token 3 consecutive times on any push or pull!

Q: I’m using Git LFS with Azure DevOps Services and I get errors when pulling files tracked by Git LFS.

A: Azure DevOps Services currently doesn’t support LFS over SSH. Use HTTPS to connect to repos with Git LFS tracked files.

microsoft.com Use SSH key authentication

4. Last but not least, there is an issue with the Microsoft implementation of LFS, which rejects large LFS objects and spits out a bunch of HTTP 413 and 503 errors at the end of your git push. It happened to me when I was pushing 40GB of UE4 binary dependencies. The weird thing was I tried twice and both times it took a few good hours till the end of the push operation and based on measuring the bandwidth usage, the LFS upload size appeared to be more than the actual upload size. According to some answers on this GitHub issue and this Microsoft developer community question, it seems the solution is running the following command inside the root of your local repository, before any git pull/push operations:

$ git config http.version HTTP/1.1

Well, not only it did the trick and worked like a charm, but also the push time on the following git push dropped dramatically to 30 minutes for that hefty 40GB UE4 binary dependencies.

OK, after getting ourselves familiarized with all the limits, if you deem this solution a worthy one for managing UE4 projects along with the engine source in the same repository, in the rest of this blog post I’m going to share my experiences and a script to keep the engine updated with ease using a Git + LFS setup.

Gregorian / Jalali (a.k.a. Persian Calendar) Date Conversion in C++ using boost::locale

Tue, 25 Feb 2020 00:27:00 +0100

Well, anyone who has ever developed a C++ game or application with Gregorian to Jalali date conversion (or, vice versa) requirement is well aware of the hurdles of doing such a task. I, for one, have been maintaining my own cross-platform C++ library for almost two decades now, with occasional bugs coming up from time to time.

Recently, I have been playing with boost::locale (developed by Artyom Beilis and contributed to Boost project) a bit more in order to utilize it in a personal project called Barandazstorm, a home-grown social media analysis tool. Browsing the docs, I noticed the following example which does not even compile on my compiler:

boost::locale Gregorian to Hebrew date conversion example

using namespace boost::locale;
using namespace boost::locale::period;
generator gen;
// Create locales with Hebrew and Gregorian (default) calendars.
std::locale l_hebrew=gen("en_US.UTF-8@calendar=hebrew");
std::locale l_gregorian=gen("en_US.UTF-8");
// Create a Gregorian date from fields
date_time greg(year(2010) + february() + day(5),l_gregorian);
// Assign a time point taken from the Gregorian date to date_time with
// the Hebrew calendar
date_time heb(greg.time(),l_hebrew);
// Now we can query the year.
std::cout << "Hebrew year is " << heb / year << std::endl;

So, I tried to make a guess and replaced the en_US.UTF-8@calendar=hebrew part with en_US.UTF-8@calendar=jalali which didn’t work. But, on the second try replacing that with en_US.UTF-8@calendar=persian actually worked! Which is sheer delight; due to the fact that now I found a solution to convert dates between both calendars as efortless as techonologies such as .NET in C++:

Two-way Gregorian / Jalali date conversion using boost::locale

/**
* @file
* @author  Mamadou Babaei <info@babaei.net>
* @version 0.1.0
*
* @section LICENSE
*
* (The MIT License)
*
* Copyright (c) 2020 Mamadou Babaei
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*
* @section DESCRIPTION
*
* Two-way Gregorian / Jalali date conversion using boost::locale example
*/

#include <iomanip>
#include <iostream>
#include <cstdlib>
#include <boost/locale.hpp>

void from_gregorian_to_jalali()
{
    boost::locale::generator generator;

    std::locale locale_gregorian = generator("en_US.UTF-8");
    std::locale locale_jalali = generator("en_US.UTF-8@calendar=persian");

    boost::locale::date_time gregorian(
            boost::locale::period::year(2020)
            + boost::locale::period::february()
            + boost::locale::period::day(25),
            locale_gregorian);

    boost::locale::date_time jalali(gregorian.time(), locale_jalali);

    std::cout << "Persian date is " << jalali / boost::locale::period::year()
            << "/" << std::setfill('0') << std::setw(2)
            << (jalali / boost::locale::period::month()) + 1
            << "/" << std::setfill('0') << std::setw(2)
            << jalali / boost::locale::period::day()
            << "." << std::endl;
}

void from_jalali_to_gregorian()
{
    boost::locale::generator generator;

    std::locale locale_gregorian = generator("en_US.UTF-8");
    std::locale locale_jalali = generator("en_US.UTF-8@calendar=persian");

    boost::locale::date_time jalali(
            boost::locale::period::year(1398)
            + boost::locale::period::month(11)
            + boost::locale::period::day(06),
            locale_jalali);

    boost::locale::date_time gregorian(jalali.time(), locale_gregorian);

    std::cout << "Gregorian date is " << gregorian / boost::locale::period::year()
            << "/" << std::setfill('0') << std::setw(2)
            << (gregorian / boost::locale::period::month()) + 1
            << "/" << std::setfill('0') << std::setw(2)
            << gregorian / boost::locale::period::day()
            << "." << std::endl;
}

int main()
{
    from_gregorian_to_jalali();
    from_jalali_to_gregorian();

    return EXIT_SUCCESS;
}

On a side note, for the above code to work your boost::locale libraries has to be built with ICU support; otherwise boost::locale throws an exception. On most Linux or BSD distros this is the default when you install Boost libraries from your distro’s package manager. On Windows, it requires a bit of effort if you are trying to build Boost binaries yourself, which is another story for another time.

I did test the above code on FreeBSD, Linux, and Microsoft Windows, using MSVC, GCC, LLVM/Clang, and MinGW, and it’s working as expected on all of these platforms.

A workaround for udevd 100% CPU usage and blank screen freeze on Gentoo GNU/Linux with recent NVIDIA drivers

Mon, 19 Aug 2019 02:37:00 +0200

A few months back due to various changes in how Funtoo is being managed, I migrated back from Funtoo to Gentoo after almost a decade. After some time I realized my laptop randomly gets stuck on a blank screen and freezes just right before my login manager (SDDM) starts. I noticed the hard-disk LED is blinking and the system is actually not freezed and probably is working and stuck on something. Checking the system or Xorg logs did not reveal anything unusual.

I even posted my issue on the Gentoo Forums and when I thought the issue is gone I marked it as SOLVED (well, I don’t turn off this laptop or reboot too much). But, the problem came back and hunted me over again.

Finally, I decided to install JuiceSSH on my phone since I do not have access to another PC for the time being. When it did freeze, I did ssh into my Gentoo installation and noticed udevd’s CPU usage is at 100%. I looked up the forums to see if someone else having this issue or not. I cannot recall where on the forums I saw it, but it seems this was a known issue to some users with recent NVIDIA drivers and someone suggested blacklisting the NVIDIA drivers, so the kernel won’t load them at boot time as it is going to be loaded by X later on.

Well, I did the following changes in order to blacklist the NVIDIA modules, so the kernel won’t load them at boot itme:

/etc/modprobe.d/blacklist.conf

blacklist nvidia
blacklist nvidia_drm
blacklist nvidia_modeset
blacklist nvidia_uvm

And, viola! It has been a month without any issues so far. It did solve the issue for me, once and for all. Hope it helps someone with a similar issue until this bug is officially fixed.

My Reddit Wallpaper Downloader Script

Wed, 08 May 2019 01:01:00 +0200

i3wm setup with amazing gruvbox color scheme and a wallpaper from Reddit

Update [2019/05/08]: Many people have been asking for the wallpaper in the above screenshot. It is from System Failure II, oil on canvas, 31x43” on r/Art.

Well, I am really fascinated by Reddit art and genuine creative ideas such as Scrolller which was made possible thanks to gazillions of art pieces scattered throughout various art subreddits. I am also fascinated by Unix philosophy and have been a *nix enthusiast for as long as I can remember. In addition to all this, the discovery of r/unixporn - realizing I am not the only one who cares about aesthetics of their Unix box - was a huge blow for me; to the point that studying the GitHub dotfiles posted along the screenshots on r/unixporn by fellow nix-enthusiast redditors felt like a day to day hubby for me.

All the while, I had a successful experiment with writing a complex piece of real-world software in pure Bash with an amazingly wide range of features for around 3.5K lines of code. The real excitement came when it made to the official FreeBSD Ports Tree. In spite of the fact that many people find Bash syntax annoyingly ugly and unmaintainable and often wonder why do people still write shell scripts by asking it on Quora, since MS-DOS 6.22 era, I did develop a certain love–hate relationship with shell scripting languages such as Batch Files, Bash, etc. Thus, still I do automate almost everything with these ancient technologies.

So, here is my fully-configurable wallpaper changer software written in bash which automagically fetches and display wallpapers from your favorite subs. It has been powering and brightening up my i3wm setup for the past eight months which led me to the conclusion that it deserves a proper introduction.

How to Run Multiplayer Call of Duty 4: Modern Warfare (Promod LIVE) using Wine on GNU/Linux

Sun, 29 Jul 2018 18:39:00 +0430

Call of Duty 4: Modern Warfare

Well, I haven’t played a multiplayer game in ages until recently, when my cool boss announced regular playtimes for all the employees in our company as a group activity in order to put the fun back into work. Since I’m a die-hard COD4 fan and I used to play Promod LIVE heavily with colleagues and friends, I proposed Call of Duty 4: Promod LIVE 220 which happened to be favored by everybody; except there was one issue: everyone uses Microsoft Windows while I’m developing UE4 games on a single-boot Funtoo Linux system.

Naturally, my first attempt was running it inside a Windows 7 virtual machine under VMWare Workstation for Linux which supports up to Direct3D 10 (the exact API used by COD4). Sadly, the experience was very poor and painful with lots of unbearable stuttering on my decent hardware. Thus, the last resort was running it under Wine, which I used to happily run many Windows applications and games under it for many years. Though, throughout those years I replaced almost every Windows application with an equivalent or an alternative Linux application until I gradually stopped using it. In the meanwhile, I also distanced myself from traditional desktop environments such as GNOME, KDE, Xfce, and LXDE, while experimenting with various window managers specially i3wm, which caught my attention for many good reasons. So, in the end I made up my mind and alienated myself from desktop environments once and for all.

Running a fully-fledged game engine such as Unreal Engine 4, I expected COD4, Wine, and i3 combination to work fine out of the box as it would under any other DE. Well, it turned out that I was too simple-minded about running a fullscreen game such as COD4 under Wine/i3wm. Hopefully, as the Wine FAQ states the workaround is super easy.

Here is the full guide on running COD4 v1.7 with Promod LIVE 2.20 on GNU/Linux.

Discourse as a Blog Comment Service on FreeBSD without Docker

Fri, 29 Apr 2016 06:49:31 +0430

Update 1 [2016/09/30]: A section has been added to the end of the article for dealing with major FreeBSD upgrades.

Update 2 [2016/09/30]: A section has been added to the end of the article for upgrading current installation of Discourse to newer versions.

Update 3 [2016/09/30]: A section has been added to the end of the article for installing Discourse under Ruby version managers which is required for dealing with newer versions of Discourse since the current system-wide version of Ruby on FreeBSD is 2.2.5p319.

Update 4 [2016/10/06]: I decided to get rid of Discourse on this blog for various reasons including negative feedback from my readers, performance issues, being a memory hog and not so easy on memory, difficult maintenance, dealing with building Ruby Gems which is a tedious task in case they fail to build and a bug that duplicates my posts and creates a new thread for each post which means it won’t show previous comments. Last but not least, in my estimation it’s too heavy for such a small task such as a comment system. As a result, this guide won’t be maintained anymore.

Figure 1. Discourse Logo

Well, when it comes to blog comment hosting services for static blogs, you will have a plethora of options such as SolidOpinion, Disqus, Livefyre, Google+ or Facebook comments, and many more. Unfortunately, such services has never been an option for me and I resisted them like forever. Yes, I’ve got one million reasons to believe and do so which demands another post of its own. So, I’ll avoid that argument for now.

This left me with two choices:

Operate my blogs without the comment section as I did for years
Running an open source self-host blog comment system such as HashOver, Isso, Juvia and talkatv

Since people asked me for a way to discuss their feedback on the website, this made the former choice a no go, anymore. So, in a search for the promised commenting system, I spent hours installing and trying every single FLOSS commenting system on GitHub. And everyone of them has had a big flaw that I could not tolerate. Finally, I came to the conclusion that I’m out of luck with that. Of course, I always had the option to write my own commenting system according to my own needs. As, I did with my own blog subscription system. But, due to the lack of time that was not an option either.

It happens that I randomly visit Coding Horror by Jeff Atwood the co-founder of Stack Overflow and Stack Exchange Network. I’ve always read the comments on Coding Horror but never had an urge to write a comment their. Since I’ve been desperately looking for a commenting system, this time the different look of its comment system catched my attention. Bingo! He wrote an open source discussion platform software named Discourse. Not necessarily a blog comment system, but could be used as one. It even supports the Farsi language and RTL out of the box which allows me to use it on my Farsi blog, too. In addition to that it supports multi-site which means I have to only run one instance for all my blogs. Just perfect!

Despite many nice feature it provides, it has a few rough edges, too. I was able to conquer some and some couldn’t, yet. But it did not stop me from integrating it into my Hexo-based blogs after two weeks of testing it. So, there it is, from now on both this blog and my Farsi blog are discussion aware :).

OK, the main issue that many people face when they want to install Discourse in a platform other than GNU/Linux, is they get hit in the face by the reading this line in the official documentation:

Why do you only officially support Docker?

Hosting Rails applications is complicated. Even if you already have Postgres, Redis and Ruby installed on your server, you still need to worry about running and monitoring your Sidekiq and Rails processes. Additionally, our Docker install comes bundled with a web-based GUI that makes upgrading to new versions of Discourse as easy as clicking a button.

How Do I Install Discourse? github.com/discourse/discourse/...

Yes, I know Ruby and Rails are crap and deploying Ruby on Rails apps are pain in the Butt. Do not worry! This was the first struggle with Discourse that I had since this blog runs on FreeBSD. And, FreeBSD support for Docker is experimental, yet. Fortunately, I used to deploy GitLab instances on FreeBSD for three years which was also RoR before I migrated to Gogs which kicks butt, anyway! That made it easy to figure out a simple way to deploy Discourse without Docker on FreeBSD.

Happy 24th Birthday: A Linux Kernel Panic At Hometown

Tue, 25 Aug 2015 21:00:00 +0430

A Linux kernel panic on tram 7B at its hometown, Helsinki (Click to enlarge)

Undeniably, flaming has been around since the dawn of the Internet age. And even worse, it has been on the rise ever since. Gazillions of flame wars on websites such as Slashdot or Reddit surely is enough proof, the greatest of which is the perennial debates between users of competing operating systems.

No doubt I’m a FLOSS enthusiast and advocate who considers free/libre/azad software superior to the proprietary ones, by all means possible. But like all software, the FLOSS ones have some shortcomings, too. So, the point is no one-hundred percent reliable software exists on this planet which means open source software may also suffer from bugs or security flaws as proprietary software do.

Today is Linux kernel birthday and many FLOSS enthusiast and advocates around the globe are going to celebrate it. I’m a diehard FreeBSD fan, but it won’t stop me from celebrating Linux birthday. In fact, I still use GNU/Linux for building native C/C++ libraries using Android NDK on a Slackware machine. In addition to that, I used to be a heavy Funtoo / Gentoo user. The thing is, I appreciate the tools I use, no matter what. So, I’m going to celebrate Linux birthday by telling you a story. A story that made an unforgettable trip even more memorable. Here’s the story of a GNU/Linux system in production which crashed in its hometown, Helsinki, Finland.

OmniBackup: One Script to back them all up

Sat, 08 Aug 2015 03:23:23 +0430

Update 1 [2016/09/23]: OmniBackup now officially supports GNU/Linux. More info…

Update 2 [2016/09/23]: Official documentation moved to GitHub which means this guide won’t be maintained anymore and maybe out of date or inaccurate.

A week ago was System Administrator Appreciation Day. It is celebrated on the last Friday in July and it has been celebrated since July 28, 2000. But, system administrators know not all days are like that day. They face many hard times and struggles during their careers and the worse of them all is either a security breech or data loss.

For so many years I’ve been writing and maintaining backup scripts on and on, for every single database I added, for every single directory with critical data, or any other service I was running on every new server I got my hands on. In the end, I found myself ended up in a pile of backup scripts and multitudinous cron entries which was a nightmare to keep track of. I even had to manage the schedule so that two backup scripts do not run at the same time. Even more, I had to manually track the backups to see whether they were successful or not. Also, someone has to manually delete the old ones to make rooms for the next ones.

Therefore, I came up with an elegant solution to replace the old process which I found exceptionally error-prone. An end to all my hardships which I call OmniBackup. At last, I’m able to confidently keep abreast of all the ever-growing data that I have to keep safe.

“So, what exactly is OmniBackup?” you may ask. “A fair question,” I would say. OmniBackup is a MIT licensed Bash script which delivers the following set of features:

Configuration and customization of backup mechanism through JSON
Support for OpenLDAP backups
Support for PostgreSQL backups as a whole or per database
Support for MariaDB and MySQL backups as a whole or per database
Support for filesystem backups with optional ability to follow symbolic links
Support for pluggable customized scripts to extend OmniBackup functionality beyond its original design which allows support for many different backup scenarios that has not been built into OmniBackup, yet
Backup file name tagging which allows including date or host name in the archive name
Online backup without a prerequisite to suspend any service
Support for customized backup tasks priority order
Support for multiple backup servers
Ability to always keep a copy of backups offline
Ability to keep a copy of backups offline if no backup server is available, or in case of an error such as a file transfer error
Secure file transfer through SSH / SCP protocol
LZMA2, gzip and bzip2 compression algorithms along with different compression levels to maintain a balance between speed and file size
Ability to preserve permissions inside backup files
Support for symmetric cryptography algorithms AES-128, AES-192 and AES-256 (a.k.a Rijndael or Advanced Encryption Standard)
Random passphrase generation for encrypted backups with variable length and patterns or a unique passphrase for all backups
Support for RSA signatures to verify the backup origin and integrity
Passphrase encryption using RSA public keys for individual backup servers
Backup integrity verification by offering hash algorithms such as MD4, MD5, MDC-2, RIPEMD160, SHA, SHA-1, SHA-224, SHA-256, SHA-384, SHA-512 and WHIRLPOOL
Optional Base64 encoding
System logs and a standalone log file including all details
Reporting through email to a list of recipients with ability to include passphrases
Customized mail subject for successful and failed backup operations
Customized support message for reports
Crontab integration
Custom temporary / working directory
Automatic and smart clean-up ability
One instance only policy which avoids running multiple instances by mistake at the same time, therefore avoids system slow-down
An example configuration file in JSON format to get you up and running

There is also a list of planned features and TODOs which did not make it into 0.1.0 release:

Restore script
GnuPG integration
SFTP and FTP support
Refactoring and code clean-up
Any potential bug fixes

Disclaimer: Please be wary of the fact that this script has approximately 3.5 K lines of Bash code and devoured hell of a time from me to write and debug. You should also consider that this is my first heavy Bash experiment and I may not write quality code in the language since I’m a newcomer to Bash. I do not claim that OmniBackup is production ready, that’s why I did version the first release at 0.1.0. Also keep in mind that OmniBackup heavily relies on 3rd-party software which increases the chance for fatal bugs, therefore losing data. So, I provide OmniBackup without any warranties, guarantees or conditions, of any kind and I accept no liability or responsibility for any misuse or damage. Please use it at your own risk and remember you are solely responsible for any resulting damage or data loss.

Credits: Many thanks go to my fellow and long-time friend, Morteza Sabetraftar for his help and ideas without whom OmniBackup lacked features or quality. Another kudos goes to my brother Amir by releasing me from shopping, cooking and house-cleaning without even mentioning it, an invaluable and priceless assistance that encouraged me even more to use my best endeavours to get this task done.

Please, feel free to clone and modify it as you wish. Pull requests for new features, improvements or bug fixes are also very welcome.

The rest of this post serves as a comprehensive guide on how to setup OmniBackup in order to backup and restore all your critical data in a production environment.

FreeBSD: Block Brute-force Attacks Using Sshguard and IPFW Firewall

Thu, 30 Jul 2015 19:56:00 +0430

There is an old saying that the only safe computer is one that’s disconnected from the network, turned off, and locked in an underground bunker—and even then you can’t be sure!

Since most of us can’t afford to keep our servers in an underground bunker, the least little thing that could have been done in order to keep their threat exposure at rock-bottom is protecting them by running a combination of a firewall and an intrusion prevention system or IPS (a.k.a intrusion detection and prevention systems or IDPS). Surely, that alone proved insufficient and other security measures and best practices should also be considered.

This blog post covers setting up a basic secure and stateful IPFW firewall on FreeBSD along with Sshguard by iXsystems Inc as intrusion prevention system.

The Proper Way of Adding a Cron Job

Thu, 11 Jun 2015 16:37:18 +0430

Until not so long ago, to add my own cron jobs I always had the habit of modifying /etc/crontab on my FreeBSD system which turned out to be wrong. In simple words, there are two types of crontab files:

System crontab which should not be altered due to the troubles it cause during FreeBSD upgrades
User crontab which has one less column than the system crontab file

Book Review: Application Development with Qt Creator - Second Edition

Mon, 29 Dec 2014 04:27:20 +0330

Almost three weeks ago I received a review request from one of the Packt Publishing staffs to review Application Development with Qt Creator, 2nd Edition written by Ray Rischpater which has been recently published by Packt Publishing. Since I’ve been developing cross platform Qt (cute, often mispronounced as Q-T cue-tee) applications from Qt 4 era back in 2008 – when Qt Creator was not around yet and the project was running by Trolltech at the time – and a handful of Qt Quick mobile applications over the past two years, I consider myself eligible enough to write a brief review on it. So, I was provided with a review copy and after reading it cover to cover, my thoughts on the book are as follows.

Application Development with Qt Creator, 2nd Edition

Getting real IP addresses using Nginx and CloudFlare

Sat, 09 Mar 2013 01:35:00 +0330

[Update]: Thanks to digitaltoast for informing me about the missing ~~real_ip_header CF-Connecting-IP;~~ from the script and providing a patch for it.

OK, I suppose you know what CloudFlare is, and are familiar with Nginx configuration process, before we proceed any further. Just in case you don’t know, CloudFlare offers free and commercial, cloud-based services to help secure and accelerate websites. The thing is, I’m really satisfied with the services they offer except a repellent issue about logging the real IP address of your website’s visitors. Since CloudFlare acts as a reverse proxy, all connections come from CloudFlare’s IP addresses, not the real visitors anymore. Anyway, using Nginx there’s a simple workaround for this issue, which I’ll describe in the rest of this post.

Colors Talk: A Colorful Terminal / Console

Sun, 03 Mar 2013 05:10:00 +0330

If you’ve ever used a GNU Gentoo or Funtoo Linux variant, or a live version of any of them, you may have noticed their eye-catching colorful terminal or console. Whether you’re on a virtual console or one of KDE, GNOME, XFCE, LXDE terminal apps.

A Colorful Xfce4 Terminal on FreeBSD (Bash)

The default Xfce4 Terminal on FreeBSD (sh csh)

When I’ve migrated from Funtoo to FreeBSD, the one thing that I’ve missed so badly was its colorful terminal. The nice thing about these colors is taht they always give you some valuable hints, e.g., currently you’re root user or a regular user, the file is a symlink (Symbolic link), executable or just a regular file.

Well, it’s pretty easy to have your own colorful terminal or console, once you’ve found out how Gentoo and Funtoo did that. Fortunately, it works on *BSD and all other Linux distros as well. So, stay with me and I’ll describe the process in the following.

nano, Syntax Highlighting

Sun, 17 Feb 2013 01:27:00 +0330

GNU nano is my favorite text editor while I’m on console. Although, it doesn’t offer syntax highlighting by default, it comes with a decent set of syntax highlighting files. Usually, these files are exist in /usr/local/share/nano or /usr/share/nano, depending on your distro’s preference. You can enable syntax highlighting for your prefered language(s) by including related file(s) with .nanorc extension in your ~/.nanorc file.

~/.nanorc - FreeBSD

include "/usr/local/share/nano/asm.nanorc"
include "/usr/local/share/nano/awk.nanorc"
include "/usr/local/share/nano/c.nanorc"
include "/usr/local/share/nano/cmake.nanorc"
include "/usr/local/share/nano/css.nanorc"
include "/usr/local/share/nano/debian.nanorc"
include "/usr/local/share/nano/fortran.nanorc"
include "/usr/local/share/nano/gentoo.nanorc"
include "/usr/local/share/nano/groff.nanorc"
include "/usr/local/share/nano/html.nanorc"
include "/usr/local/share/nano/java.nanorc"
include "/usr/local/share/nano/makefile.nanorc"
include "/usr/local/share/nano/man.nanorc"
include "/usr/local/share/nano/mgp.nanorc"
include "/usr/local/share/nano/mutt.nanorc"
include "/usr/local/share/nano/nanorc.nanorc"
include "/usr/local/share/nano/objc.nanorc"
include "/usr/local/share/nano/ocaml.nanorc"
include "/usr/local/share/nano/patch.nanorc"
include "/usr/local/share/nano/perl.nanorc"
include "/usr/local/share/nano/php.nanorc"
include "/usr/local/share/nano/pov.nanorc"
include "/usr/local/share/nano/python.nanorc"
include "/usr/local/share/nano/ruby.nanorc"
include "/usr/local/share/nano/sh.nanorc"
include "/usr/local/share/nano/tcl.nanorc"
include "/usr/local/share/nano/tex.nanorc"
include "/usr/local/share/nano/xml.nanorc"

~/.nanorc - Funtoo or Gentoo

include "/usr/share/nano/asm.nanorc"
include "/usr/share/nano/awk.nanorc"
include "/usr/share/nano/c.nanorc"
include "/usr/share/nano/cmake.nanorc"
include "/usr/share/nano/css.nanorc"
include "/usr/share/nano/debian.nanorc"
include "/usr/share/nano/fortran.nanorc"
include "/usr/share/nano/gentoo.nanorc"
include "/usr/share/nano/groff.nanorc"
include "/usr/share/nano/html.nanorc"
include "/usr/share/nano/java.nanorc"
include "/usr/share/nano/makefile.nanorc"
include "/usr/share/nano/man.nanorc"
include "/usr/share/nano/mgp.nanorc"
include "/usr/share/nano/mutt.nanorc"
include "/usr/share/nano/nanorc.nanorc"
include "/usr/share/nano/objc.nanorc"
include "/usr/share/nano/ocaml.nanorc"
include "/usr/share/nano/patch.nanorc"
include "/usr/share/nano/perl.nanorc"
include "/usr/share/nano/php.nanorc"
include "/usr/share/nano/pov.nanorc"
include "/usr/share/nano/python.nanorc"
include "/usr/share/nano/ruby.nanorc"
include "/usr/share/nano/sh.nanorc"
include "/usr/share/nano/tcl.nanorc"
include "/usr/share/nano/tex.nanorc"
include "/usr/share/nano/xml.nanorc"

Note: If the file doesn’t exist, you should create it first:

$ touch ~/.nanorc

nano, Do Not Wrap Text

Sun, 17 Feb 2013 01:13:00 +0330

GNU nano is my favorite text editor while I’m on console. However, there’s one thing about nano which annoys me: automatic text wrapping!

Hopefully, there are two simple ways to overcome this. By using either -w command-line argument, or set nowrap configuration command within the file ~/.nanorc.

1. The temporary solution by using -w command-line argument, which should be used each time you run nano:

$ nano -w /path/to/file

2. The permanent solution by setting off automatic text wrapping using the configuration command set nowrap, in the ~/.nanorc file:

~/.nanorc

set nowrap

Note: If the file doesn’t exist, you should create it first:

$ touch ~/.nanorc

Write Your Own Cross-Platform Cryptographic Library

Fri, 15 Feb 2013 08:11:00 +0330

Previously I’ve described the process of building Crypto++ on both FreeBSD and Windows using the GCC, MinGW and VC++ compilers.

Now, we want to develop our own cross-platform cryptographic wrapper library around Crypto++. I’ve already uploaded the full source code to GitHub. You can find the link to the code on GitHub at the end of this article.

Before you proceed, you have to build the Crypto++ library as I mentioned earlier here.

How to Build C++ Cryptographic Library, Crypto++

Fri, 15 Feb 2013 03:50:00 +0330

Crypto++ is an awesome free and open source C++ class library of cryptographic algorithms and schemes which fully supports 32-bit and 64-bit architectures for many major operating systems, including FreeBSD, Linux, Solaris, Windows, Mac OS X and iOS. Currently, Crypto++ officially supports the following compilers:

MSVC 6.0 - 2010
GCC 3.3 - 4.5
C++Builder 2010
Intel C++ Compiler 9 - 11.1
Sun Studio 12u1, Express 11/08, Express 06/10

The latest version at the time of this writing is 5.6.1.

In spite of the power that Crypto++ offers, building and using it can be a little bit tricky. In the following we will describe the process of building Crypto++ on both FreeBSD and Windows using the GCC, MinGW and VC++ compilers.