From 2e9d88ed765a0eb43a0adb32f9990f2ea5f42bf9 Mon Sep 17 00:00:00 2001
From: Kwarde <kevin@kwarde.com>
Date: Sat, 5 Jul 2025 02:28:59 +0200
Subject: [PATCH] Adds print(), puts()

---
 src/console.asm | 46 ++++++++++++++++++++++++++++++++++++++++++++++
 src/core.asm    |  1 +
 src/tests.asm   | 21 +++++++++++++++++++++
 3 files changed, 68 insertions(+)

diff --git a/src/console.asm b/src/console.asm
index 2e069bf..438352d 100644
--- a/src/console.asm
+++ b/src/console.asm
@@ -1 +1,47 @@
 %include "src/constants.asm"
+
+extern	strlen
+
+section .rodata
+	mNL	db	NL
+section .text
+	global	print
+	global	puts
+
+;----- print(*str[]) -----;
+; Prints given string to the console to stdout
+; Return value: Amount of printed characters
+; Used registers:
+;	rax*	syscall >> (ret) amount of printed characters
+;	rdi*	(arg) Pointer to str[] >> syscall arg (fd)
+;	rsi*	syscall arg (pointer to str[])
+;	rdx*	syscall arg (length of str[])
+print:
+	sub	rsp, SIZE_QWORD
+	mov	rsi, rdi
+	call	strlen
+	mov	rdx, rax
+	mov	rax, NR_write
+	mov	rdi, FD_stdout
+	syscall
+	add	rsp, SIZE_QWORD
+	ret
+
+;----- puts(*str[]) -----;
+; Prints given string to the console to stdout and prints a new line
+; Return value: Amount of printed characters
+; Used registers:
+;
+puts:
+	sub	rsp, SIZE_QWORD
+	call	print
+	mov	rsi, mNL
+	mov	r10, rax
+	mov	rax, NR_write
+	mov	rdi, FD_stdout
+	mov	rdx, 1
+	syscall
+	mov	rax, r10
+	inc	rax
+	add	rsp, SIZE_QWORD
+	ret
diff --git a/src/core.asm b/src/core.asm
index a4e0a01..9911208 100644
--- a/src/core.asm
+++ b/src/core.asm
@@ -10,5 +10,6 @@ section .text
 ;	rax*	syscall
 ;	rdi	(arg) code to exit the program with
 exit:
+	sub	rsp, SIZE_QWORD
 	mov	rax, NR_exit
 	syscall
diff --git a/src/tests.asm b/src/tests.asm
index 6870e54..2240063 100644
--- a/src/tests.asm
+++ b/src/tests.asm
@@ -3,13 +3,22 @@
 ; core.asm
 extern	exit
 ; console.asm
+extern	print
+extern	puts
 ; string.asm
 extern	strlen
 ; convert.asm
 
 section .rodata
+	TEST_print		equ	1
 	TEST_strlen		equ	1
 
+	; print()
+	msgPrint		db	"TEST print()",NL,EOS
+
+	; puts()
+	msgPuts			db	"TEST puts()",EOS
+
 	; strlen()
 	strlenStr1		db	"Hello",EOS
 	strlenStr2		db	"Hello, world!",NL,EOS
@@ -25,6 +34,18 @@ _start:
 	mov	rbp, rsp
 	sub	rsp, SIZE_QWORD
 
+;---
+;--- print()
+;---
+	lea	rdi, [rel msgPrint]
+	call	print
+
+;---
+;--- puts()
+;---
+	lea	rdi, [rel msgPuts]
+	call	puts
+
 ;---
 ;--- strlen()
 ;---