add rp6502 target

libsrc/rp6502/sysrename.c

@@ -0,0 +1,32 @@
+/*
+ * Copyright (c) 2023 Rumbledethumps
+ *
+ * SPDX-License-Identifier: Zlib
+ * SPDX-License-Identifier: BSD-3-Clause
+ * SPDX-License-Identifier: Unlicense
+ */
+
+#include <rp6502.h>
+#include <errno.h>
+#include <string.h>
+
+unsigned char __fastcall__ _sysrename(const char *oldpath, const char *newpath)
+{
+    size_t oldpathlen, newpathlen;
+    oldpathlen = strlen(oldpath);
+    newpathlen = strlen(newpath);
+    if (oldpathlen + newpathlen > 254)
+    {
+        return _mappederrno(EINVAL);
+    }
+    while (oldpathlen)
+    {
+        ria_push_char(oldpath[--oldpathlen]);
+    }
+    ria_push_char(0);
+    while (newpathlen)
+    {
+        ria_push_char(newpath[--newpathlen]);
+    }
+    return ria_call_int_errno(RIA_OP_RENAME);
+}