pudquick

Reproducible Builds for macOS

There's a neat writeup I stumbled across recently titled "Reproducible codesigning on Apple Silicon" from Keith Smiley about some gotchas when it comes to compiling a binary in a way that's repeatable and always generates the exact same byte output (which would then checksum to the exact same hash) - even if compiled on a different Mac.

In applying the suggestions I found in the blog post, I found a few other corner cases that I just wanted to get documented more explicitly somewhere.

Tools Matter

Footnote 2 from that blog post is important:

ibireme

// =============================================================================
// XNU kperf/kpc demo
// Available for 64-bit Intel/Apple Silicon, macOS/iOS, with root privileges
//
//
// Demo 1 (profile a function in current thread):
// 1. Open directory '/usr/share/kpep/', find your CPU PMC database.
//    M1 (Pro/Max/Ultra): /usr/share/kpep/a14.plist
//    M2 (Pro/Max):       /usr/share/kpep/a15.plist
//    M3:                 /usr/share/kpep/as1.plist

saagarjha

// If you haven't already, make sure to run this so the window list works:
// defaults write com.apple.QuartzDebug QuartzDebugPrivateInterface -bool YES

// https://gist.github.com/saagarjha/ed701e3369639410b5d5303612964557
#import "swizzler.h"
#import <AppKit/AppKit.h>

static Swizzler<void, id<NSApplicationDelegate>, NSNotification *> QuartzDebug_applicationDidFinishLaunching_ {
	NSClassFromString(@"QuartzDebug"), @selector(applicationDidFinishLaunching:), [](auto self, auto notification) {
		QuartzDebug_applicationDidFinishLaunching_(self, notification);

davelevine

How to Properly Cache Content Hosted on Backblaze B2

Summary

Because I use Cloudflare to manage my domains and Backblaze for backups, it only made sense to take advantage of their Bandwidth Alliance for creating my own CDN. This has been incredibly helpful for image hosting for this knowledge base, however, I recently noticed that caching wasn't working as it should.

The Problem

The overall problem started when I was adding a parking page for a domain I recently purchased. The background image was hosted on B2 and the image was supposed to be cached by Cloudflare. However, each time the page loaded, it would pull the image from the origin instead of the cache. I checked this on my knowledge base and found it was doing the same thing.

gotdibbs

# Safely move chia plots from one drive to another on Windows

$SOURCE_DIR = 'A:\Chia'
$DEST_DIR = 'B:\Chia'

$move_count = 0;

while (($plot_to_move = (Get-ChildItem $SOURCE_DIR -Filter '*.plot' | Select-Object -First 1)) -ne $null) {
    $old_name = $plot_to_move.Name
    # Temporarily rename the plot before moving https://github.com/Chia-Network/chia-blockchain/wiki/Moving-plots

rustymagnet3000

iOS app introspection

• Jailbreak in 2024
  • Steps
  • Find jailbreak
  • Prepare iOS device
  • Prepare XCode for older iOS versions
• Create Provisioning Profile in XCode

tclementdev

libdispatch efficiency tips

The libdispatch is one of the most misused API due to the way it was presented to us when it was introduced and for many years after that, and due to the confusing documentation and API. This page is a compilation of important things to know if you're going to use this library. Many references are available at the end of this document pointing to comments from Apple's very own libdispatch maintainer (Pierre Habouzit).

My take-aways are:

• You should create very few, long-lived, well-defined queues. These queues should be seen as execution contexts in your program (gui, background work, ...) that benefit from executing in parallel. An important thing to note is that if these queues are all active at once, you will get as many threads running. In most apps, you probably do not need to create more than 3 or 4 queues.

• Go serial first, and as you find performance bottle necks, measure why, and if concurrency helps, apply with care, always validating under system pressure. Reuse

P1kachu

#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <mach-o/dyld.h>
#include <mach-o/nlist.h>
#include <mach-o/dyld_images.h>
#include <mach/mach_vm.h>

/* Dyld is the OSX Dynamic Linker
 * /usr/include//mach-o/loader.h

natecook1000

// Curry Recipe

func curryRecipe(n: Int) -> String {
    let types = join(", ", map(1...n, { "T\($0)" }))
    let returnType = join(" -> ", map(1...n, { "T\($0)" }))
    let closures = join(" in ", map(1...n, { "{ t\($0)" }))
    let braces = join(" ", Array(count: n, repeatedValue: "}"))
    return "func curry<\(types), R>(f: (\(types)) -> R) -> \(returnType) -> R {\r" +
        "    return \(closures) in f(\(types.lowercaseString)) \(braces)\r}"
}

nfarina

#import <UIKit/UIKit.h>

@interface UIView (SMFrameAdditions)

@property (nonatomic, assign) CGPoint $origin;
@property (nonatomic, assign) CGSize $size;
@property (nonatomic, assign) CGFloat $x, $y, $width, $height; // normal rect properties
@property (nonatomic, assign) CGFloat $left, $top, $right, $bottom; // these will stretch the rect

@end