param: Build param without linker script

Changed to enable the posix_sitl_simple target to build and run

param show *

without using a linker script

Signed-off-by: Mark Charlebois <charlebm@gmail.com>

Tools/px_generate_params.py

@@ -0,0 +1,53 @@
+#!/usr/bin/env python
+import xml.etree.ElementTree as ET
+import os
+
+if len(os.sys.argv) != 3:
+	print "Error in %s" % os.sys.argv[0]
+	print "Usage: %s <parameters.xml> <parameters.c>"
+	raise SystemExit
+
+fp = open(os.sys.argv[2], "w")
+
+tree = ET.parse(os.sys.argv[1])
+root = tree.getroot()
+body = """
+#include <stdint.h>
+#include <systemlib/param/param.h>
+
+// DO NOT EDIT
+// This file is autogenerated from paramaters.xml
+
+"""
+
+start_name = ""
+end_name = ""
+
+for group in root:
+	if group.tag == "group":
+		body += "// %s\n" % group.attrib["name"]
+		for param in group:
+			if not start_name:
+				start_name = param.attrib["name"]
+			end_name = param.attrib["name"]
+			body += """ 
+static const
+__attribute__((used, section("__param")))
+struct param_info_s __param__%s = {
+	"%s",
+	PARAM_TYPE_%s,
+	.val.f = %s
+};
+""" % (param.attrib["name"], param.attrib["name"], param.attrib["type"], param.attrib["default"])
+body += """
+extern const
+__attribute__((alias("__param__%s")))
+struct param_info_s __param_start;
+
+extern const
+__attribute__((alias("__param__%s")))
+struct param_info_s __param_end;
+""" % (start_name, end_name)
+
+fp.write(body)
+