feature (libnx): implemented basic math utils

libnx/inc/public/nox/math.h

@@ -5,7 +5,9 @@
 
 #include "stdtypes.h"
 
-uint64_t min(uint64_t a, uint64_t b);
-uint64_t max(uint64_t a, uint64_t b);
+int64_t min(int64_t a, int64_t b);
+int64_t max(int64_t a, int64_t b);
+double  pow(double base, int64_t exponent);
+int64_t abs(int64_t n);
 
 #endif //LIBNX_MATH_H

libnx/src/math.c

@@ -2,10 +2,31 @@
 
 #include "public/nox/math.h"
 
-uint64_t min (uint64_t a, uint64_t b) {
+int64_t min(int64_t a, int64_t b) {
     return a < b ? a : b;
 }
 
-uint64_t max (uint64_t a, uint64_t b) {
+int64_t max(int64_t a, int64_t b) {
     return a > b ? a : b;
 }
+double pow(double base, int64_t exponent) {
+    double result = 1;
+
+    if (exponent >= 0) {
+        for (int i = 0; i < exponent; i++) {
+            result *= base;
+        }
+    } else {
+        for (int i = 0; i < abs(exponent); i++) {
+            result /= base;
+        }
+    }
+    return result;
+}
+
+int64_t abs(int64_t n) {
+    if (n < 0) {
+        return n * -1;
+    }
+    return n;
+}