download aria2c bat file

downloadAria2c.bat

@echo off

if not exist "%~dp0aria2c.exe" (
  echo Downloading aria2c.exe...
  powershell -Command "(New-Object Net.WebClient).DownloadFile('https://uupdump.ml/autodl_files/aria2c.exe', '%~dp0aria2c.exe')"
)
call :checkhash "3eb8712b0db6ba466f8afe1bf606983fe8341c941bdfcadc07068288c7ca5a9c" "aria2c.exe"

goto start

:checkhash
  for /F "skip=1" %%i in ('certutil -hashfile %~2 SHA256') do set CURRHASH=%%i & goto HaveValue
  :HaveValue
  set CURRHASH=%CURRHASH: =%

  if not "%~1" == "%CURRHASH%" (
    del %~2
    echo "%~2 hash does not match"
    goto halt
  )
goto :EOF

:halt
call :haltHelper 2> nul

:haltHelper
() 
exit /b

:start

echo "hi there"

https://stackoverflow.com/questions/10534911/how-can-i-exit-a-batch-file-from-within-a-function