fay59

Here's a list of mildly interesting things about the C language that I learned mostly by consuming Clang's ASTs. Although surprises are getting sparser, I might continue to update this document over time.

There are many more mildly interesting features of C++, but the language is literally known for being weird, whereas C is usually considered smaller and simpler, so this is (almost) only about C.

1. Combined type and variable/field declaration, inside a struct scope [https://godbolt.org/g/Rh94Go]

struct foo {
   struct bar {
 int x;

fay59

use std::cmp;

fn spiral_distance(num: u32) -> u32 {
	let ring = (((num as f64).sqrt() - 1.) / 2.).ceil() as u32;
	let root = (num as f64 - 1.).sqrt() as u32;
	let offset_to_mid = root / 2;
	let ring_min = root * root + 1 + offset_to_mid;
	let ring_max = (root + 1) * (root + 1) - offset_to_mid;
	return ring + cmp::min(
		(num as i32 - ring_min as i32).abs(),

fay59

import networkx as nx


class DominatorTreeNode(object):
	__slots__ = ("value", "depth", "parent", "children")

	def __init__(self, value):
		self.value = value
		self.depth = None
		self.parent = None

fay59

precedencegroup ExponentPrecedence {
	associativity: right
	higherThan: MultiplicationPrecedence
}

infix operator **: ExponentPrecedence

fileprivate enum Expr: CustomStringConvertible {
	case Int(n: Int)
	indirect case Var(x: String)

fay59

fn digits_to_vec(digits: String) -> Vec<u32> {
    let mut result = Vec::new();
    for c in digits.chars() {
        match c.to_digit(10) {
            Some(v) => result.push(v),
            None => {}
        }
    }
    return result;
}

fay59

fn digits_to_vec(digits: String) -> Vec<u32> {
    let mut result = Vec::new();
    for c in digits.chars() {
        match c.to_digit(10) {
            Some(v) => result.push(v),
            None => {}
        }
    }
    return result;
}

fay59

'''
Solution to the realism challenge from CSAW'17 Quals.
https://github.com/isislab/CSAW-CTF-2017-Quals/tree/master/rev/realism
'''
from z3 import *

s = Solver()

# This is a simplification of the array of bytes found at 0x7D90:
# 0xff => 1, 0x00 => 0; where 1 means "include this value in the psadbw sum"

fay59

(*

To use:

1- Launch Photos
2- Select photos for which you want to set the GPS location based on a .gpx file
3- Adjust date/time of photos (if necessary)
4- Launch script, select GPX file, wait

*)

fay59

%option noyywrap
%x C_COMMENT

%%

"/*"            { BEGIN(C_COMMENT); }
<C_COMMENT>"*/" { BEGIN(INITIAL); }
<C_COMMENT>.    { }
<C_COMMENT>\n   { }

fay59

#!/bin/bash

# requires jq
# arg 1: iCloud web album URL
# arg 2: folder to download into (optional)

function curl_post_json {
	curl -sH "Content-Type: application/json" -X POST -d "@-" "$@"
}