Félix Cloutier 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;

	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(),

	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

	precedencegroup ExponentPrecedence {
	associativity: right
	higherThan: MultiplicationPrecedence
	}

	infix operator **: ExponentPrecedence

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

	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;
	}

	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;
	}

	'''
	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"

	(*

	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

	*)

	%option noyywrap
	%x C_COMMENT

	%%

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

	#!/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 "@-" "$@"
	}