From e718e1534bdd89601c325461888f3b6cf07c2ffb Mon Sep 17 00:00:00 2001
From: Kwarde <kevin@kwarde.com>
Date: Tue, 15 Jul 2025 16:39:19 +0200
Subject: [PATCH] printf: Add format specifier %p

---
 src/console.asm |  9 +++++++++
 src/tests.asm   | 16 ++++++++++++++--
 2 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/src/console.asm b/src/console.asm
index 701243e..cc23377 100644
--- a/src/console.asm
+++ b/src/console.asm
@@ -69,6 +69,8 @@ puts:
 ;	%X	Unsigned integer, printed as hexadecimal number (uppercase)
 ;	%b	Unsigned integer, printed as binary number
 ;	%o	Unsigned integer, printed as octal number
+;	%p	Print pointer, but truly alias for %#x -- this printf/udec processes all arguments as qwords so both %x and %p (and other specifiers) will always print full true value.
+;		That is also why %l/%ll is not supported - it's not needed.
 ;	%s	String
 ;	%#{x}	Use prefix for printed number (non-decimal). Supported specifiers: x, X, b, o. Works in combination with width specifier (see below)
 ;	%[#]n*	Pad left, n chars (maximum 64). Supported specifiers: d, i, u, x, X, b, o
@@ -281,6 +283,8 @@ printf:
 		je	.rep_b
 		cmp	byte [rdi + 1], 'o'
 		je	.rep_o
+		cmp	byte [rdi + 1], 'p'
+		je	.rep_p
 		cmp	byte [rdi + 1], 's'
 		je	.rep_s
 
@@ -329,6 +333,11 @@ printf:
 		.rep_o:
 			process_arg 8, 0, utoa
 
+		;--- '%p' ---;
+		.rep_p:
+		mov	r15, 1 ;always force prefix, no matter if %p or %#p was used. Do not override padding though
+			process_arg 16, 0, utoa
+
 		;--- '%s' ---;
 		.rep_s:
 			load_arg rsi
diff --git a/src/tests.asm b/src/tests.asm
index daf35a6..76427a3 100644
--- a/src/tests.asm
+++ b/src/tests.asm
@@ -99,9 +99,10 @@ section .rodata
 	printf12Str		db	"\nRAX\t%064b\nEAX\t\t\t\t\t%032b\n AX\t\t\t\t\t\t\t%016b\n AH\t\t\t\t\t\t\t%08b\t\n AL\t\t\t\t\t\t\t\t%08b\n",EOS
 	printf13		db	TAB,"printf(",DQUO,"%o | %8o | %08o\n",DQUO,", 1500, 1500, 1500): ",NL,TAB,TAB,EOS
 	printf13Str		db	"%o | %8o | %08o\n",EOS
-	printf14		db	TAB,"printf(",DQUO,"%#b | %#08b | %#x | %#8X\n | %#o",DQUO,", 8, 8, 0xABCDEF, 0x12345678, 15): ",NL,TAB,TAB,EOS
+	printf14		db	TAB,"printf(",DQUO,"%#b | %#08b | %#x | %#8X | %#o\n",DQUO,", 8, 8, 0xABCDEF, 0x12345678, 15): ",NL,TAB,TAB,EOS
 	printf14Str		db	"%#b | %#08b | %#x | %#8X | %#o\n",EOS
-
+	printf15		db	TAB,"printf(",DQUO,"%p | %#p | %8p | %08p | %#08p\n",DQUO,", 0xabc, 0xabc, 0xabc, 0xabc, 0xabc): ",NL,TAB,TAB,EOS
+	printf15Str		db	"%p | %#p | %8p | %08p | %#08p\n",EOS
 	; strlen()
 	msgStrlen		db	NL,"TEST strlen()",NL,EOS
 	strlen1			db	TAB,"strlen(str1): %d",NL,EOS
@@ -396,6 +397,17 @@ _start:
 	mov	r8, 0x12345678
 	mov	r9, 15
 	call	printf
+
+	; TEST 15
+	lea	rdi, [rel printf15]
+	call	print
+	lea	rdi, [rel printf15Str]
+	mov	rsi, 0xabc
+	mov	rdx, 0xabc
+	mov	rcx, 0xabc
+	mov	r8, 0xabc
+	mov	r9, 0xabc
+	call	printf
 %endif
 
 ;---