*******************
Templates
*******************

These pages contain quick reference guides to NASM.

.. toctree::
   :maxdepth: 3

.. _nasm_template:

NASM Template
================

.. note::
    Please see :ref:`posix_env_setup` to install the required packages
    and libraries.

.. code-block:: text

    ; include directives
    global asm_main
    %include "../lib/asm_io.inc"

    segment .data
        ; DX directives (read only, static data)

    segment .bss
        ; RESX directives (writable data)

    segment .text
    asm_main:                    ; entry point (called from driver.c)
        ; instructions

        enter 0,0                ; Initialize register EBP
        pusha                    ; Push register contents to the stack
        ;
        ; Your program here
        ;
        popa                     ; Restore register data from the stack
        mov eax, 0               ; flush EAX of data
        leave                    ; restore the stack
        ret                      ; Return from main back into C library wrapper

Makefile 32-bit Template
===========================

.. note::
    - A Makefile requires the use of tabs (ASCII symbol ``HT``,
      code ``0x09``) instead of blank spaces.
    - HTML does not display a tab or HT. You will need to copy/paste
      a HT from notepad if your text editor does not support tabs.
    - Here is the error code that you will receive if you do not use
      a tab on line number 2.

      .. code-block:: bash

          Makefile:2: *** missing separator.  Stop.

.. code-block:: make

    # compiles the project files (project_name.asm)
    # Compiles dependencies if they are not up to date
    project_name: asm_io.o driver.o project_name.o
        @echo "Building project_name.asm"
        @gcc -m32 driver.o project_name.o asm_io.o -o project_name
        @rm project_name.o		# Remove project_name.o to force a recompile each time
        ./project_name

    # Build project_name.asm
    project_name.o:
        @nasm -f elf project_name.asm -o project_name.o

    # Build asm_io.asm
    asm_io.o:
        @nasm -f elf -d ELF_TYPE ../lib/asm_io.asm -o asm_io.o

    # Build driver.c
    driver.o:
        @gcc -m32 -c ../lib/driver.c -o driver.o

    # Clean up and then rebuild all (asm_io.asm, driver.c, and project_name.asm)
    all: clean project_name

    # Removes all .o and temporary files
    clean:
        @echo "Cleaning up..."
        @rm -f *.o
        @rm -f project_name

.. admonition:: Source & license
   :class: note

   Reproduced **verbatim, without modification** from
   `© 2022, BilimEdtech Labs <https://labs.bilimedtech.com/index.html>`__,
   licensed under
   `Creative Commons Attribution 4.0 International (CC BY 4.0) <https://creativecommons.org/licenses/by/4.0/deed.en>`__.

   Source page:
   https://labs.bilimedtech.com/nasm/resources/templates.html

   See :doc:`LICENSE <../../LICENSE_edtech>` for the full license text.