Updating to reflect the latest work

[zilutils.git] / zilasm / header.cpp

diff --git a/zilasm/header.cpp b/zilasm/header.cpp
new file mode 100644 (file)
index 0000000..863c65e
--- /dev/null
+++ b/zilasm/header.cpp
@@ -0,0 +1,68 @@
+/*
+ * header.c -- part of ZilUtils/ZilAsm
+ *
+ * Copyright (C) 2016, 2019 Jason Self <j@jxself.org>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ * SPDX-License-Identifier: AGPL-3.0-or-later
+ */
+
+#include <string.h>            /* bzero */
+#include <assert.h>
+#include <stdio.h>
+
+#include "header.h"
+
+Program_header_struct Program_header;
+
+const unsigned MAX_HEADER_LEN = 40;
+
+void
+program_header_reset (unsigned zversion)
+{
+  bzero (&Program_header, sizeof (Program_header));
+  Program_header.version = zversion;
+}
+
+ZMemblock *
+program_header_build (void)
+{
+  ZMemblock *zmb = zmem_init (MAX_HEADER_LEN);
+  zmem_putbyte (zmb, Program_header.version);
+  /* TODO */
+  return zmb;
+}
+
+
+Word
+swapBytes (Word w)
+{
+  return ((w & 255) << 8) + (w >> 8);
+}
+
+
+void
+outputToFile (Program_header_struct * pHeader, FILE * file)
+{
+  Program_header_struct h;
+  memcpy (&h, pHeader, sizeof (Program_header_struct));
+
+  h.startPC = swapBytes (h.startPC);
+  h.h_file_size = swapBytes (h.h_file_size);
+  h.H_STRINGS_OFFSET = swapBytes (h.H_STRINGS_OFFSET);
+
+  int size = sizeof (Program_header_struct);
+  fwrite (&h, sizeof (Program_header_struct), 1, file);
+}