docs: add newline after aur badge

README.md

@@ -31,7 +31,7 @@ it to be.
 # Installation
 **NOTE:** Hilbish is currently only officially supported and tested on Linux
 
-### Prebuilt binaries
+## Prebuilt binaries
 Binaries are provided for the latest commit.  
 
 **Note that these use Hilbiline, not readline, and may be missing functionality
@@ -44,24 +44,25 @@ Then click on the artifacts drop down, and download artifact for your platform,
 like what is highlighted in the screenshot.  
 <br><img src="https://modeus.is-inside.me/KJ0Puceb.png"><br>
 
-### AUR
+## AUR
-![AUR maintainer](https://img.shields.io/aur/maintainer/hilbish?logo=arch-linux&style=flat-square)  
+[![AUR maintainer](https://img.shields.io/aur/maintainer/hilbish?logo=arch-linux&style=flat-square)](https://aur.archlinux.org/packages/hilbish)  
 Arch Linux users can install Hilbish from the AUR with the following command:  
 ```sh
 yay -S hilbish
 ```
+
+[![AUR maintainer](https://img.shields.io/aur/maintainer/hilbish?logo=arch-linux&style=flat-square)](https://aur.archlinux.org/packages/hilbish-git)  
 Or from the latest `master` commit with:  
 ```sh
 yay -S hilbish-git
 ```
 
-### Nixpkgs
+## Nixpkgs
 Nix/NixOS users can install Hilbish from the central repository, nixpkgs, through the usual ways.
-
 If you're new to nix you should probably read up on how to do that [here](https://nixos.wiki/wiki/Cheatsheet).
 
-### Manual Build
+## Manual Build
-#### Prerequisites
+### Prerequisites
 - [Go 1.16+](https://go.dev)
 - GNU Readline
 

aliases.go

@@ -2,6 +2,7 @@ package main
 
 import (
 	"strings"
+	"sync"
 
 	"github.com/yuin/gopher-lua"
 )
@@ -10,16 +11,21 @@ var aliases *hilbishAliases
 
 type hilbishAliases struct {
 	aliases map[string]string
+	mu *sync.RWMutex
 }
 
 // initialize aliases map
 func NewAliases() *hilbishAliases {
 	return &hilbishAliases{
 		aliases: make(map[string]string),
+		mu: &sync.RWMutex{},
 	}
 }
 
 func (h *hilbishAliases) Add(alias, cmd string) {
+	h.mu.Lock()
+	defer h.mu.Unlock()
+
 	h.aliases[alias] = cmd
 }
 
@@ -28,10 +34,16 @@ func (h *hilbishAliases) All() map[string]string {
 }
 
 func (h *hilbishAliases) Delete(alias string) {
+	h.mu.Lock()
+	defer h.mu.Unlock()
+
 	delete(h.aliases, alias)
 }
 
 func (h *hilbishAliases) Resolve(cmdstr string) string {
+	h.mu.RLock()
+	defer h.mu.RUnlock()
+
 	args := strings.Split(cmdstr, " ")
 	for h.aliases[args[0]] != "" {
 		alias := h.aliases[args[0]]