Implement string concatenate and repeat operatorsexpressions

This patch exercises the new expression infrastructure to implement syntax
to concatenate and repeat strings.  We use syntax inspired by Python,
with '+' overloaded for string concatenation and '*' overloaded for string
repeat.  Normally we'd use C syntax to inspire dts syntax, but C has no
obvious candidates for these string operators.

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

1 files changed, 97 insertions, 0 deletions

diff --git a/tests/string-expressions.c b/tests/string-expressions.c
new file mode 100644
index 0000000..da6854f
--- /dev/null
+++ b/tests/string-expressions.c
@@ -0,0 +1,97 @@
+/*
+ * Testcase for dtc string expression support
+ *
+ * Copyright (C) 2013 David Gibson <david@gibson.dropbear.id.au>
+ *
+ * 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 <errno.h>
+
+
+#include <libfdt.h>
+
+#include "tests.h"
+#include "testdata.h"
+
+struct test_expr {
+	const char *expr;
+	const char *result;
+} expr_table[] = {
+#define TE(expr, res)	{ #expr, (res) }
+	TE("hello", "hello"),
+	TE("hello " + "world", "hello world"),
+	TE("hello" + " " + "world", "hello world"),
+	TE("hello" * 2 + " world", "hellohello world"),
+	TE("hello " + 2 * "world", "hello worldworld"),
+	TE(("hello"), "hello"),
+	TE(0 ? "hello" : "goodbye", "goodbye"),
+	TE(1 ? "hello" : "goodbye", "hello"),
+};
+
+#define ARRAY_SIZE(x)	(sizeof(x) / sizeof((x)[0]))
+
+int main(int argc, char *argv[])
+{
+	void *fdt;
+	const char *res;
+	int reslen;
+	int i;
+
+	test_init(argc, argv);
+
+	if ((argc == 3) && (strcmp(argv[1], "-g") == 0)) {
+		FILE *f = fopen(argv[2], "w");
+
+		if (!f)
+			FAIL("Couldn't open \"%s\" for output: %s\n",
+			     argv[2], strerror(errno));
+
+		fprintf(f, "/dts-v1/;\n");
+		fprintf(f, "/ {\n");
+		for (i = 0; i < ARRAY_SIZE(expr_table); i++)
+			fprintf(f, "\texpression-%d = %s;\n", i,
+				expr_table[i].expr);
+		fprintf(f, "};\n");
+		fclose(f);
+	} else {
+		fdt = load_blob_arg(argc, argv);
+
+		for (i = 0; i < ARRAY_SIZE(expr_table); i++) {
+			char propname[16];
+			int len = strlen(expr_table[i].result) + 1;
+
+			sprintf(propname, "expression-%d", i);
+			res = fdt_getprop(fdt, 0, propname, &reslen);
+
+			if (reslen != len)
+				FAIL("Incorrect length for expression %s,"
+				     " %d instead of %d\n",
+				     expr_table[i].expr, reslen, len);
+
+			if (memcmp(res, expr_table[i].result, len) != 0)
+				FAIL("Incorrect result for expression %s,"
+				     " \"%s\" instead of \"%s\"\n",
+				     expr_table[i].expr, res,
+				     expr_table[i].result);
+		}
+	}
+
+	PASS();
+}