lib: c: implement strcpy and strncpy

lib/libc/core/string/strcpy.c

@@ -0,0 +1,26 @@
+char *strcpy(char *output, const char *input)
+{
+	unsigned int i;
+	for (i = 0; input[i] != 0; i++) {
+		output[i] = input[i];
+	}
+
+	output[i] = '\0';
+	return output;
+}
+
+char *strncpy(char *output, const char *input, unsigned int count)
+{
+	unsigned int size = count;
+	unsigned int i;
+	for (i = 0; i < size; i++) {
+		output[i] = input[i];
+
+		if (input[i] == 0) {
+			break;
+		}
+	}
+
+	output[i] = '\0';
+	return output;
+}

lib/libc/include/string.h

@@ -11,6 +11,9 @@ extern size_t strlen(const char *s);
 extern int strcmp(const char *s1, const char *s2);
 extern int strncmp(const char *s1, const char *s2, unsigned long n);
 
+extern int strcpy(const char *s1, const char *s2);
+extern int strncpy(const char *s1, const char *s2, unsigned long n);
+
 extern void *memset(void *str, int c, size_t n);
 extern void *memcpy(void *dst, const void *src, size_t len);