decompile util

4 files changed, 98 insertions, 157 deletions

diff --git a/asm/util.s b/asm/util.s
deleted file mode 100644
index 3b3f95a..0000000
--- a/asm/util.s
+++ /dev/null
@@ -1,156 +0,0 @@
-	.include "constants/gba_constants.inc"
-	.include "asm/macros.inc"
-
-	.syntax unified
-
-	.text
-
-	thumb_func_start ReverseString
-ReverseString:
-	push {r4,r5,lr}
-	adds r3, r0, 0
-	subs r4, r1, 0x1
-	adds r2, r3, r4
-	movs r5, 0
-	cmp r5, r4
-	bge _08004566
-_08004552:
-	ldrb r1, [r3]
-	ldrb r0, [r2]
-	strb r0, [r3]
-	adds r3, 0x1
-	strb r1, [r2]
-	subs r2, 0x1
-	adds r5, 0x1
-	subs r4, 0x1
-	cmp r5, r4
-	blt _08004552
-_08004566:
-	pop {r4,r5}
-	pop {r0}
-	bx r0
-	thumb_func_end ReverseString
-
-	thumb_func_start ConvertToDecimal
-ConvertToDecimal:
-	push {r4-r7,lr}
-	adds r4, r1, 0
-	cmp r4, 0
-	ble _08004578
-	movs r7, 0x1
-	b _0800457E
-_08004578:
-	negs r4, r4
-	movs r7, 0x1
-	negs r7, r7
-_0800457E:
-	cmp r2, 0
-	ble _080045A0
-	adds r6, r0, 0
-	adds r5, r2, 0
-_08004586:
-	adds r0, r4, 0
-	movs r1, 0xA
-	bl __modsi3
-	stm r6!, {r0}
-	adds r0, r4, 0
-	movs r1, 0xA
-	bl __divsi3
-	adds r4, r0, 0
-	subs r5, 0x1
-	cmp r5, 0
-	bne _08004586
-_080045A0:
-	adds r0, r7, 0
-	pop {r4-r7}
-	pop {r1}
-	bx r1
-	thumb_func_end ConvertToDecimal
-
-	thumb_func_start ConvertFromDecimal
-ConvertFromDecimal:
-	push {r4,r5,lr}
-	adds r4, r0, 0
-	adds r5, r1, 0
-	ldm r4!, {r1}
-	movs r3, 0xA
-	cmp r2, 0x1
-	ble _080045CA
-	subs r2, 0x1
-_080045B8:
-	ldm r4!, {r0}
-	muls r0, r3
-	adds r1, r0
-	subs r2, 0x1
-	lsls r0, r3, 2
-	adds r0, r3
-	lsls r3, r0, 1
-	cmp r2, 0
-	bne _080045B8
-_080045CA:
-	adds r0, r1, 0
-	cmp r5, 0
-	bge _080045D2
-	negs r0, r0
-_080045D2:
-	pop {r4,r5}
-	pop {r1}
-	bx r1
-	thumb_func_end ConvertFromDecimal
-
-	thumb_func_start ConvertFromBCD
-ConvertFromBCD:
-	push {r4,lr}
-	adds r1, r0, 0
-	movs r2, 0x1
-	movs r3, 0
-	cmp r1, 0
-	ble _080045FA
-	movs r4, 0xF
-_080045E6:
-	adds r0, r1, 0
-	ands r0, r4
-	muls r0, r2
-	adds r3, r0
-	lsls r0, r2, 2
-	adds r0, r2
-	lsls r2, r0, 1
-	asrs r1, 4
-	cmp r1, 0
-	bgt _080045E6
-_080045FA:
-	adds r0, r3, 0
-	pop {r4}
-	pop {r1}
-	bx r1
-	thumb_func_end ConvertFromBCD
-
-	thumb_func_start ConvertToBCD
-ConvertToBCD:
-	push {r4-r6,lr}
-	adds r4, r0, 0
-	movs r5, 0
-	movs r6, 0
-	cmp r4, 0
-	ble _0800462C
-_08004610:
-	adds r0, r4, 0
-	movs r1, 0xA
-	bl __modsi3
-	lsls r0, r5
-	adds r6, r0
-	adds r5, 0x4
-	adds r0, r4, 0
-	movs r1, 0xA
-	bl __divsi3
-	adds r4, r0, 0
-	cmp r4, 0
-	bgt _08004610
-_0800462C:
-	adds r0, r6, 0
-	pop {r4-r6}
-	pop {r1}
-	bx r1
-	thumb_func_end ConvertToBCD
-
-	.align 2, 0 @ Don't pad with nop.
diff --git a/include/util.h b/include/util.h
new file mode 100644
index 0000000..3da2beb
--- /dev/null
+++ b/include/util.h
@@ -0,0 +1,10 @@
+#ifndef GUARD_UTIL_H
+#define GUARD_UTIL_H
+
+void ReverseString(u8 *s, s32 len);
+s32 ConvertToDecimal(s32 *decimal, s32 n, s32 len);
+s32 ConvertFromDecimal(s32 *decimal, s32 sign, s32 len);
+s32 ConvertFromBCD(s32 bcd);
+s32 ConvertToBCD(s32 n);
+
+#endif // GUARD_UTIL_H
diff --git a/ld_script.txt b/ld_script.txt
index 07163b1..14d1053 100644
--- a/ld_script.txt
+++ b/ld_script.txt
@@ -38,7 +38,7 @@ SECTIONS {
         asm/memory.o(.text);
         asm/code_80035F0.o(.text);
         src/other_random.o(.text);
-        asm/util.o(.text);
+        src/util.o(.text);
         asm/bg_palette_buffer.o(.text);
         asm/code_80047E8.o(.text);
         src/random.o(.text);
diff --git a/src/util.c b/src/util.c
new file mode 100644
index 0000000..0c9c2dd
--- /dev/null
+++ b/src/util.c
@@ -0,0 +1,87 @@
+#include "global.h"
+#include "util.h"
+
+void ReverseString(u8 *s, s32 len)
+{
+    u8 *l = s;
+    s32 right = len - 1;
+    u8 *r = s + right;
+    s32 left = 0;
+
+    while (left < right)
+    {
+        u8 temp = *l;
+        *l++ = *r;
+        *r-- = temp;
+        left++;
+        right--;
+    }
+}
+
+s32 ConvertToDecimal(s32 *decimal, s32 n, s32 len)
+{
+    s32 sign;
+    s32 i;
+
+    if (n > 0)
+    {
+        sign = 1;
+    }
+    else
+    {
+        n = -n;
+        sign = -1;
+    }
+
+    for (i = 0; i < len; i++)
+    {
+        decimal[i] = n % 10;
+        n /= 10;
+    }
+
+    return sign;
+}
+
+s32 ConvertFromDecimal(s32 *decimal, s32 sign, s32 len)
+{
+    s32 i;
+    s32 powerOfTen;
+    s32 n = *decimal++;
+
+    for (i = 1, powerOfTen = 10; i < len; i++, powerOfTen *= 10)
+    {
+        n += *decimal++ * powerOfTen;
+    }
+
+    return (sign < 0) ? -n : n;
+}
+
+s32 ConvertFromBCD(s32 bcd)
+{
+    s32 powerOfTen = 1;
+    s32 n = 0;
+
+    while (bcd > 0)
+    {
+        n += (bcd & 0xF) * powerOfTen;
+        powerOfTen *= 10;
+        bcd >>= 4;
+    }
+
+    return n;
+}
+
+s32 ConvertToBCD(s32 n)
+{
+    s32 shift = 0;
+    s32 bcd = 0;
+
+    while (n > 0)
+    {
+        bcd += (n % 10) << shift;
+        shift += 4;
+        n /= 10;
+    }
+
+    return bcd;
+}