dtc: Implement path references

This patch extends dtc syntax to allow references (&label, or
&{/full/path}) directly within property definitions, rather than
inside a cell list.  Such references are expanded to the full path of
the referenced node, as a string, instead of to a phandle as
references within cell lists are evaluated.

A testcase is also included.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

1 files changed, 83 insertions, 0 deletions

diff --git a/tests/path-references.c b/tests/path-references.c
new file mode 100644
index 0000000..b96c5b2
--- /dev/null
+++ b/tests/path-references.c
@@ -0,0 +1,83 @@
+/*
+ * libfdt - Flat Device Tree manipulation
+ *	Testcase for string references in dtc
+ * Copyright (C) 2006 David Gibson, IBM Corporation.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public License
+ * as published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdint.h>
+
+#include <fdt.h>
+#include <libfdt.h>
+
+#include "tests.h"
+#include "testdata.h"
+
+void check_ref(const void *fdt, int node, const char *checkpath)
+{
+	const char *p;
+	int len;
+
+	p = fdt_getprop(fdt, node, "ref", &len);
+	if (!p)
+		FAIL("fdt_getprop(%d, \"ref\"): %s", node, fdt_strerror(len));
+	if (!streq(p, checkpath))
+		FAIL("'ref' in node at %d has value \"%s\" instead of \"%s\"",
+		     node, p, checkpath);
+
+	p = fdt_getprop(fdt, node, "lref", &len);
+	if (!p)
+		FAIL("fdt_getprop(%d, \"lref\"): %s", node, fdt_strerror(len));
+	if (!streq(p, checkpath))
+		FAIL("'lref' in node at %d has value \"%s\" instead of \"%s\"",
+		     node, p, checkpath);
+}
+
+int main(int argc, char *argv[])
+{
+	void *fdt;
+	const char *p;
+	int len, multilen;
+	int n1, n2;
+
+	test_init(argc, argv);
+	fdt = load_blob_arg(argc, argv);
+
+	n1 = fdt_path_offset(fdt, "/node1");
+	if (n1 < 0)
+		FAIL("fdt_path_offset(/node1): %s", fdt_strerror(n1));
+	n2 = fdt_path_offset(fdt, "/node2");
+	if (n2 < 0)
+		FAIL("fdt_path_offset(/node2): %s", fdt_strerror(n2));
+
+	check_ref(fdt, n1, "/node2");
+	check_ref(fdt, n2, "/node1");
+
+	/* Check multiple reference */
+	multilen = strlen("/node1") + strlen("/node2") + 2;
+	p = fdt_getprop(fdt, 0, "multiref", &len);
+	if (!p)
+		FAIL("fdt_getprop(0, \"multiref\"): %s", fdt_strerror(len));
+	if (len != multilen)
+		FAIL("multiref has wrong length, %d instead of %d",
+		     len, multilen);
+	if ((!streq(p, "/node1") || !streq(p + strlen("/node1") + 1, "/node2")))
+		FAIL("multiref has wrong value");
+
+	PASS();
+}