unit: Create unit test for SSID UTF8 pretty-printing

Write a set of tests that check correct and incorrect UTF8 sequences
at the beginning, middle and end of a byte array. Also verify an all
zeros (hidden) SSID of varying length.

Makefile.am

@@ -70,7 +70,8 @@ noinst_PROGRAMS = tools/hwsim
 tools_hwsim_LDADD = ell/libell-internal.la
 
 unit_tests = unit/test-pbkdf2-sha1 unit/test-prf-sha1 unit/test-ie \
-		unit/test-crypto unit/test-mpdu unit/test-eapol
+		unit/test-crypto unit/test-mpdu unit/test-eapol \
+		unit/test-ssid-to-utf8
 
 if MAINTAINER_MODE
 noinst_PROGRAMS += $(unit_tests)
@@ -99,6 +100,11 @@ unit_test_mpdu_LDADD = ell/libell-internal.la
 unit_test_eapol_SOURCES = unit/test-eapol.c \
 				src/eapol.h src/eapol.c
 unit_test_eapol_LDADD = ell/libell-internal.la
+
+unit_test_ssid_to_utf8_SOURCES = src/util.h src/util.c \
+				unit/test-ssid-to-utf8.c
+unit_test_ssid_to_utf8_LDADD = ell/libell-internal.la
+
 TESTS = $(unit_tests)
 
 manual_pages = doc/iwmon.1

unit/test-ssid-to-utf8.c

@@ -0,0 +1,87 @@
+/*
+ *
+ *  Wireless daemon for Linux
+ *
+ *  Copyright (C) 2014  Intel Corporation. All rights reserved.
+ *
+ *  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
+ *
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+#include <ell/ell.h>
+
+#include "src/util.h"
+
+struct ssid_test_data {
+	size_t len;
+	uint8_t ssid[32];
+	const char *string;
+	bool result;
+};
+
+const struct ssid_test_data ssid_samples[] = {
+	{ 0, { }, "", true },
+	{ 1, { }, "", true },
+	{ 32, { }, "", true },
+	{ 33, { }, "", true },
+	{ 33, { 'a', 'b', 'c', }, "", true },
+	{ 42, { }, "", true },
+	{ 3, { 'f', 'o', 'o', }, "foo", true },
+	{ 3, { }, "", true },
+	{ 3, { 'f', 'o', 'o', }, "bar", false },
+	{ 3, { 'f', 'o', 'o', 0xff, }, "foo", true },
+	{ 5, { 'f', 'o', 'o', 'b', 'a', 'r' }, "fooba", true },
+	{ 5, { 'f', 'o', 'o', 'b', 'a', 'r' }, "foobar", false },
+	{ 5, { 'f', 'o', 'o', 'b', 'a', 'r' }, "oobar", false },
+	{ 4, { 'x', 'y', 'z', 0xff }, "xyz<EFBFBD>", true },
+	{ 6, { 'x', 'y', 'z', 0xff, '1', '2' }, "xyz<EFBFBD>12", true },
+	{ 7, { 0xf0, 0xf3, '3', '4', '5', '6', '7', }, "<EFBFBD><EFBFBD>34567", true },
+	{ 6, { 0xc3, 0x96, '3', '4', '5', '6' }, "Ö3456", true },
+	{ 6, { '1', 0xc3, 0x96, '4', '5', '6' }, "1Ö456", true },
+	{ 6, { '1', '2', '3', '4', 0xc3, 0x96 }, "1234Ö", true },
+};
+
+static void ssid_to_utf8(const void *data)
+{
+	const struct ssid_test_data *ssid = data;
+	int i = 0, samples = sizeof(ssid_samples) / sizeof(ssid_samples[0]);
+
+	while (i < samples) {
+		const char *result = util_ssid_to_utf8(ssid[i].len,
+						ssid[i].ssid);
+
+		assert(!memcmp(ssid[i].string, result,
+				strlen(ssid[i].string)) == ssid[i].result);
+
+		i++;
+	}
+
+}
+
+int main(int argc, char *argv[])
+{
+	l_test_init(&argc, &argv);
+
+	l_test_add("/util/ssid_to_utf8/", ssid_to_utf8, ssid_samples);
+
+	return l_test_run();
+}