From a54742b2ff5483f8fd1d0221acd9ae3faf4d462e Mon Sep 17 00:00:00 2001
From: bemxio <bemxiov@protonmail.com>
Date: Tue, 10 Sep 2024 15:29:15 +0200
Subject: [PATCH] add hex support to ultoa

---
 src/kernel/commands.c   | 12 ++++++------
 src/kernel/lib/stdlib.c | 38 ++++++++++++++++++++++++++++++++++++--
 src/kernel/lib/stdlib.h |  2 +-
 3 files changed, 43 insertions(+), 9 deletions(-)

diff --git a/src/kernel/commands.c b/src/kernel/commands.c
index e27ce13..6a588ba 100644
--- a/src/kernel/commands.c
+++ b/src/kernel/commands.c
@@ -54,7 +54,7 @@ void peek(char* token) {
     unsigned int offset = address & 0xffff;
 
     unsigned char value;
-    char* buffer;
+    char buffer[4];
 
     __asm__ (
         "movw %1, %%ax\n"
@@ -66,7 +66,7 @@ void peek(char* token) {
         : "ax", "si", "es"
     );
 
-    ultoa(value, buffer);
+    ultoa(value, buffer, 10);
     puts(buffer);
 
     putchar('\r');
@@ -212,13 +212,13 @@ void _int(char* token) {
         :: "ax", "bx", "cx", "dx", "si", "di"
     );
 
-    char* buffer;
+    char buffer[7];
 
     for (unsigned char i = 0; i < 6; i++) {
         puts(names[i]);
         putchar('=');
 
-        ultoa(registers[i], buffer);
+        ultoa(registers[i], buffer, 16);
         puts(buffer);
 
         putchar(' ');
@@ -298,7 +298,7 @@ void read(char* token) {
     if (status != 0) {
         puts("Disk read failed with error code ");
 
-        ultoa(status, token);
+        ultoa(status, token, 16);
         puts(token);
         
         putchar('.');
@@ -377,7 +377,7 @@ void write(char* token) {
     if (status != 0) {
         puts("Disk write failed with error code ");
 
-        ultoa(status, token);
+        ultoa(status, token, 16);
         puts(token);
 
         putchar('.');
diff --git a/src/kernel/lib/stdlib.c b/src/kernel/lib/stdlib.c
index ddc850c..e0c4076 100644
--- a/src/kernel/lib/stdlib.c
+++ b/src/kernel/lib/stdlib.c
@@ -65,8 +65,8 @@ unsigned long atoul(const char* nptr) {
     return __atoul_dec(nptr);
 }
 
-char* ultoa(unsigned long n, char* buf) {
-    int i = 0;
+char* __ultoa_dec(unsigned long n, char* buf) {
+    unsigned char i = 0;
 
     if (n == 0) {
         buf[i++] = '0';
@@ -80,4 +80,38 @@ char* ultoa(unsigned long n, char* buf) {
     strrev(buf);
 
     return buf;
+}
+
+char* __ultoa_hex(unsigned long n, char* buf) {
+    unsigned char i = 0;
+
+    if (n == 0) {
+        buf[i++] = '0';
+    } else {
+        for (unsigned long x = n; x > 0; x /= 16) {
+            unsigned long r = x % 16;
+
+            if (r < 10) {
+                buf[i++] = r + 48;
+            } else {
+                buf[i++] = r + 55;
+            }
+        }
+    }
+
+    buf[i++] = 'x';
+    buf[i++] = '0';
+    buf[i] = '\0';
+
+    return strrev(buf);
+}
+
+char* ultoa(unsigned long n, char* buf, char base) {
+    if (base == 10) {
+        return __ultoa_dec(n, buf);
+    } else if (base == 16) {
+        return __ultoa_hex(n, buf);
+    }
+
+    return NULL;
 }
\ No newline at end of file
diff --git a/src/kernel/lib/stdlib.h b/src/kernel/lib/stdlib.h
index fb7503d..d03da76 100644
--- a/src/kernel/lib/stdlib.h
+++ b/src/kernel/lib/stdlib.h
@@ -4,6 +4,6 @@
 #include "string.h"
 
 unsigned long atoul(const char* nptr);
-char* ultoa(unsigned long n, char* buf);
+char* ultoa(unsigned long n, char* buf, char base);
 
 #endif
\ No newline at end of file