CString: Support strcpy(), strcat() and strchr()

luna/include/luna/CString.h

@@ -16,4 +16,9 @@ extern "C"
 
     // Copies len bytes from src into dest and adds a null terminator.
     void nullcpy(char* dest, const char* src, usize len);
+
+    [[deprecated]] char* strcpy(char* dst, const char* src);
+    [[deprecated]] char* strcat(char* dst, const char* src);
+
+    char* strchr(const char* str, int c);
 }

luna/src/CString.cpp

@@ -81,4 +81,28 @@ extern "C"
         memcpy(dest, src, len);
         dest[len] = 0;
     }
+
+    char* strcpy(char* dest, const char* src)
+    {
+        char* s = dest;
+        for (; *src; dest++, src++) *dest = *src;
+        *dest = 0;
+        return s;
+    }
+
+    char* strcat(char* dest, const char* src)
+    {
+        char* s = dest;
+        while (*dest) dest++;
+        for (; *src; dest++, src++) *dest = *src;
+        *dest = 0;
+        return s;
+    }
+
+    char* strchr(const char* str, int c)
+    {
+        while (*str && *str != c) str++;
+        if (*str) return const_cast<char*>(str);
+        return NULL;
+    }
 }