Organize libc and libm files (#1499)

* memmove

* strcpy

* strcmp

* memset

* fmodf

* fix some missing includes

* Remove libc header dependencies on libultra

* fix

* review

src/boot/O2/__osMemset.c

@@ -1,11 +0,0 @@
-#include "global.h"
-
-void* __osMemset(void* ptr, s32 val, size_t size) {
-    u8* dst = ptr;
-    register s32 rem;
-
-    for (rem = size--; rem != 0; rem = size--) {
-        *dst++ = val;
-    }
-    return ptr;
-}

src/boot/libc/memmove.c

@@ -1,9 +1,9 @@
-#include "global.h"
+#include "libc/string.h"
 
-void* __osMemcpy(void* dst, void* src, size_t size) {
-    u8* _dst = dst;
-    u8* _src = src;
-    register s32 rem;
+void* memmove(void* dst, const void* src, size_t size) {
+    unsigned char* _dst = dst;
+    const unsigned char* _src = src;
+    register size_t rem;
 
     if (_dst == _src) {
         return dst;

src/boot/libc/memset.c

@@ -0,0 +1,12 @@
+#include "libc/string.h"
+
+void* memset(void* ptr, int val, size_t size) {
+    unsigned char* dst = ptr;
+    register size_t rem;
+
+    for (rem = size--; rem != 0; rem = size--) {
+        *dst++ = val;
+    }
+
+    return ptr;
+}

src/boot/libc/strcmp.c

@@ -1,12 +1,13 @@
-#include "global.h"
+#include "libc/string.h"
 
-s32 __osStrcmp(const char* str1, const char* str2) {
-    char c1;
-    char c2;
+int strcmp(const char* str1, const char* str2) {
+    unsigned char c1;
+    unsigned char c2;
 
     do {
         c1 = *str1++;
         c2 = *str2++;
+
         if (c1 != c2) {
             return c1 - c2;
         }

src/boot/libc/strcpy.c

@@ -1,6 +1,6 @@
-#include "global.h"
+#include "libc/string.h"
 
-char* __osStrcpy(char* dst, const char* src) {
+char* strcpy(char* dst, const char* src) {
     char* _dst = dst;
 
     while (*src != '\0') {

src/boot/libc64/__osMalloc.c

@@ -1,10 +1,10 @@
 #include "libc64/os_malloc.h"
 
 #include "alignment.h"
-#include "functions.h" // for __osMemcpy
 #include "libc/stdbool.h"
 #include "libc/stdint.h"
-#include "macros.h" // for ARRAY_COUNT
+#include "libc/string.h"
+#include "macros.h"
 
 #define FILL_ALLOCBLOCK (1 << 0)
 #define FILL_FREEBLOCK (1 << 1)
@@ -374,7 +374,7 @@ void* __osRealloc(Arena* arena, void* ptr, size_t newSize) {
                 next2 = (void*)((uintptr_t)next + diff);
                 node->next = next2;
                 node->size = newSize;
-                __osMemcpy(next2, next, sizeof(ArenaNode));
+                memmove(next2, next, sizeof(ArenaNode));
             } else {
                 // Create a new pointer and manually copy the data from the old pointer to the new one
                 newPtr = __osMalloc(arena, newSize);

src/boot/libm/fmodf.c

@@ -1,7 +1,7 @@
-#include "global.h"
+#include "libc/math.h"
 
-f32 fmodf(f32 dividend, f32 divisor) {
-    s32 quotient;
+float fmodf(float dividend, float divisor) {
+    int quotient;
 
     if (divisor == 0.0f) {
         return 0.0f;