feat: Linux compatibility (looking for NASM in PATH) (#1)

* feat: Linux compatibility (looking for NASM in PATH)
* just a tiny bit of cleanup/normalizing to my goofy code formatting

main.py

@@ -1,6 +1,7 @@
 import os
 import sys
 import ctypes
+import shutil
 import struct
 import subprocess
 
@@ -31,7 +32,6 @@ def p16(value):
 #------------------------------------------------------------------------------
 
 BASE_PATH = os.path.join(os.path.dirname(__file__))
-NASM_PATH = os.path.join(BASE_PATH, "nasm.exe")
 ENDGAME_PATH = os.path.join(BASE_PATH, "ENDGAME")
 
 #
@@ -78,15 +78,25 @@ def compile_shellcode(shellcode_filepath, debug=False):
     """
     assert shellcode_filepath.endswith(".asm")
 
-    # Run nasm.exe and capture the output and errors
-    command = [NASM_PATH, shellcode_filepath]
+    # for Windows-based systems just use the local nasm.exe included in the repo
+    if os.name == "nt":
+        nasm_executable = os.path.join(BASE_PATH, "nasm.exe")
+
+    # for POSIX systems (linux, macOS) look for nasm in the system path
+    elif os.name == "posix":
+        if not shutil.which("nasm"):
+            raise FileNotFoundError("NASM cannot be found in PATH")
+        nasm_executable = "nasm"
+
+    command = [nasm_executable, shellcode_filepath]
     if debug:
         command.insert(1, "-dDEBUG")
 
+    # run nasm and capture the output and errors
     print("[*] Assembling shellcode... ", end="")
     result = subprocess.run(command, capture_output=True)
 
-    # Check the return code of the command
+    # check the return code to determine if compilation succeeded
     if result.returncode == 0:
         output = result.stdout.decode()
         if output.strip():