implement basic dynamic string

c_os/user/lib/String.cc

@@ -0,0 +1,37 @@
+#include "user/lib/String.h"
+#include "user/lib/Math.h"
+#include "user/lib/Memory.h"
+
+unsigned int bse::strlen(const char* str) {
+    const char* current = str;
+    while (*current != '\0') { ++current; }
+    return current - str;
+}
+
+void bse::strncpy(char* destination, unsigned int n, const char* source) {
+    memcpy<char>(destination, source, n);
+}
+
+// Only compares equal length strings
+int bse::strcmp(const char* a, const char* b) {
+    const unsigned int a_len = strlen(a);
+    const unsigned int b_len = strlen(b);
+
+    if (a_len < b_len) {
+        return -1;
+    }
+    if (b_len < a_len) {
+        return 1;
+    }
+
+    for (unsigned int i = 0; i < a_len; ++i) {
+        if (a[i] < b[i]) {
+            return -1;
+        }
+        if (b[i] < a[i]) {
+            return 1;
+        }
+    }
+
+    return 0;
+}