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@andrewseidl
andrewseidl / Clang-format Comparison.md
Last active July 13, 2025 00:00
Clang-format style comparison

This is a comparison of the different formatting styles including with clang-format.

Generated via:

styles=( LLVM Google Chromium Mozilla WebKit )
for style in $styles
do
  clang-format -style=$style ChLcpIterativeAPGD.h > ChLcpIterativeAPGD.$style.h

done

@vszakats
vszakats / s3-upload-aws4.sh
Last active April 29, 2025 07:26
AWS S3 upload using signature v4
#!/bin/sh
# To the extent possible under law, Viktor Szakats
# has waived all copyright and related or neighboring rights to this
# script.
# CC0 - https://creativecommons.org/publicdomain/zero/1.0/
# SPDX-License-Identifier: CC0-1.0
# THIS SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
@jlafon
jlafon / dynamodb.md
Created December 3, 2014 05:03
An Introduction to Amazon's DynamoDB

An introduction to DynamoDB

DynamoDB is a powerful, fully managed, low latency, NoSQL database service provided by Amazon. DynamoDB allows you to pay for dedicated throughput, with predictable performance for "any level of request traffic". Scalability is handled for you, and data is replicated across multiple availability zones automatically. Amazon handles all of the pain points associated with managing a distributed datastore for you, including replication, load balancing, provisioning, and backups. All that is left is for you to take your data, and its access patterns, and make it work in the denormalized world of NoSQL.

Modeling your data

The single most important part of using DynamoDB begins before you ever put data into it: designing the table(s) and keys. Keys (Amazon calls them primary keys) can be composed of one attribute, called a hash key, or a compound key called the hash and range key. The key is used to uniquely identify an item in a table. The choice of the primary key is particularl

@soarez
soarez / ca.md
Last active July 27, 2025 23:20
How to setup your own CA with OpenSSL

How to setup your own CA with OpenSSL

For educational reasons I've decided to create my own CA. Here is what I learned.

First things first

Lets get some context first.

@gitaarik
gitaarik / git_submodules.md
Last active October 28, 2025 05:24
Git Submodules basic explanation

Git Submodules - Basic Explanation

Why submodules?

In Git you can add a submodule to a repository. This is basically a sub-repository embedded in your main repository. This can be very useful. A couple of usecases of submodules:

  • Separate big codebases into multiple repositories.
@noteed
noteed / docker-ovs.md
Last active December 29, 2023 07:07
Docker - Open vSwitch setup
def verify_sign(public_key_loc, signature, data):
'''
Verifies with a public key from whom the data came that it was indeed
signed by their private key
param: public_key_loc Path to public key
param: signature String signature to be verified
return: Boolean. True if the signature is valid; False otherwise.
'''
from Crypto.PublicKey import RSA
from Crypto.Signature import PKCS1_v1_5
@niw
niw / libpng_test.c
Last active June 9, 2025 00:00
How to read and write PNG file using libpng. Covers trivial method calls like png_set_filler.
/*
* A simple libpng example program
* http://zarb.org/~gc/html/libpng.html
*
* Modified by Yoshimasa Niwa to make it much simpler
* and support all defined color_type.
*
* To build, use the next instruction on OS X.
* $ brew install libpng
* $ clang -lz -lpng16 libpng_test.c
@jikamens
jikamens / encryption.py
Last active August 11, 2017 03:49
Python code for Schematics field encryption / decryption that is compatible with Ruby's mongoid-encrypted-fields + gibberish. The Encryptor object in this gist does encryption / decryption that is compatible with "openssl enc -k *password* -salt -aes-256-cbc". If you want it also to be compatible with mongoid-encrypted-fields, then you need to s…
import binascii
from Crypto.Cipher import AES
from Crypto.Random.random import getrandbits
from hashlib import md5
from schematics.types import StringType
import struct
class DecryptionException(Exception):
pass
@aspyct
aspyct / signal.c
Last active February 19, 2024 11:24
Unix signal handling example in C, SIGINT, SIGALRM, SIGHUP...
/**
* More info?
* [email protected]
* http://aspyct.org
*
* Hope it helps :)
*/
#include <stdio.h>
#include <stdlib.h>