[open source] make_prepatcher

whats so special about a patch maker?

It creates a patch so you don't have to download through the nexon patcher, which turns out to stop loading sometimes. While it's true it's easy to create, it's quite handy.

Edit:

 15-min lsp

Code:

(defconstant *buffer-size* 4096) ; Change to yer liking. Max is array-total-size-limit.

(defmacro with-open-files (files &body body)
    (loop for x in `,files
          for expr = `(with-open-file ,x ,@body) then `(with-open-file ,x ,expr)
          finally (return expr)))
          
(defun wU (bits stream n)
    (do ((x bits (- x 8)))
        ((not (plusp x)) t)
        (write-byte (ash n (- x)) stream)))
        
(defun copy-data (in out)
    (let ((buf (make-array *buffer-size* :element-type 'unsigned-byte)))
        (loop for pos = (read-byte-sequence buf in)
            while (plusp pos)
        do (write-byte-sequence buf out :end pos))))

          
(defun make-patch (&rest in-to)
    (let* ((inpath (format nil "~{~5,'0d~^to~}.patch" in-to))
           (outpath (format nil "~{~5,'0d~^to~}.exe" in-to)))
    (with-open-files ((in inpath :direction :input
                                 :if-exists :supersede
                                 :element-type 'unsigned-integer)
                      (out outpatch :direction :output
                                    :element-type 'unsigned-integer)
                      (base-patch "ManualPatch.base" :direction :input
                                                     :element-type 'unsigned-integer))
        (copy-data base-patch out)
        (copy-data in out)
        (wU 64 out (file-length in))
        (write-byte-sequence #(0 0 0 0 0 0 0 0 #xF3 #xFB #xF7 #xF2) out))))

;(make-patch 66 67)