unit-tests: implement the unit-testing framework

This set of patches adds a simple unit-testing framework to Busybox

unit-tests: add some helper macros for unit-test framework implementation
unit-tests: implement the unit-testing framework
unit-tests: add basic documentation on writing the unit test cases
unit-tests: modify the Makefile 'test' target to run unit-tests too
unit-tests: add two example test cases
unit-tests: modify the existing strrstr test code to use the unit-test framework

Signed-off-by: Bartosz Golaszewski <bartekgola@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

libbb/bbunit.c

@@ -0,0 +1,90 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * bbunit: Simple unit-testing framework for Busybox.
+ *
+ * Copyright (C) 2014 by Bartosz Golaszewski <bartekgola@gmail.com>
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
+ */
+
+//kbuild:lib-$(CONFIG_UNIT_TEST) += bbunit.o
+//applet:IF_UNIT_TEST(APPLET(unit, BB_DIR_USR_BIN, BB_SUID_DROP))
+
+//usage:#define unit_trivial_usage
+//usage:       ""
+//usage:#define unit_full_usage "\n\n"
+//usage:       "Run the unit-test suite"
+
+#include "libbb.h"
+
+#define WANT_TIMING 0
+
+static llist_t *tests = NULL;
+static unsigned tests_registered = 0;
+static int test_retval;
+
+void bbunit_registertest(struct bbunit_listelem *test)
+{
+	llist_add_to_end(&tests, test);
+	tests_registered++;
+}
+
+void bbunit_settestfailed(void)
+{
+	test_retval = -1;
+}
+
+#if WANT_TIMING
+static void timeval_diff(struct timeval* res,
+				const struct timeval* x,
+				const struct timeval* y)
+{
+	long udiff = x->tv_usec - y->tv_usec;
+
+	res->tv_sec = x->tv_sec - y->tv_sec - (udiff < 0);
+	res->tv_usec = (udiff >= 0 ? udiff : udiff + 1000000);
+}
+#endif
+
+int unit_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM) MAIN_EXTERNALLY_VISIBLE;
+int unit_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
+{
+	unsigned tests_run = 0;
+	unsigned tests_failed = 0;
+#if WANT_TIMING
+	struct timeval begin;
+	struct timeval end;
+	struct timeval time_spent;
+	gettimeofday(&begin, NULL);
+#endif
+
+	bb_error_msg("Running %d test(s)...", tests_registered);
+	for (;;) {
+		struct bbunit_listelem* el = llist_pop(&tests);
+		if (!el)
+			break;
+		bb_error_msg("Case: [%s]", el->name);
+		test_retval = 0;
+		el->testfunc();
+		if (test_retval < 0) {
+			bb_error_msg("[ERROR] [%s]: TEST FAILED", el->name);
+			tests_failed++;
+		}
+		tests_run++;
+		el = el->next;
+	}
+
+#if WANT_TIMING
+	gettimeofday(&end, NULL);
+	timeval_diff(&time_spent, &end, &begin);
+	bb_error_msg("Elapsed time %u.%06u seconds"
+			(int)time_spent.tv_sec,
+			(int)time_spent.tv_usec);
+#endif
+	if (tests_failed > 0) {
+		bb_error_msg("[ERROR] %u test(s) FAILED", tests_failed);
+		return EXIT_FAILURE;
+	}
+	bb_error_msg("All tests passed");
+	return EXIT_SUCCESS;
+}

libbb/obscure.c

@@ -182,3 +182,41 @@ int FAST_FUNC obscure(const char *old, const char *newval, const struct passwd *
 	}
 	return 0;
 }
+
+#if ENABLE_UNIT_TEST
+
+/* Test obscure_msg() instead of obscure() in order not to print anything. */
+
+static const struct passwd pw = {
+	.pw_name = (char *)"johndoe",
+	.pw_gecos = (char *)"John Doe",
+};
+
+BBUNIT_DEFINE_TEST(obscure_weak_pass)
+{
+	/* Empty password */
+	BBUNIT_ASSERT_NOTNULL(obscure_msg("Ad4#21?'S|", "", &pw));
+	/* Pure numbers */
+	BBUNIT_ASSERT_NOTNULL(obscure_msg("Ad4#21?'S|", "23577315", &pw));
+	/* Similar to pw_name */
+	BBUNIT_ASSERT_NOTNULL(obscure_msg("Ad4#21?'S|", "johndoe123%", &pw));
+	/* Similar to pw_gecos, reversed */
+	BBUNIT_ASSERT_NOTNULL(obscure_msg("Ad4#21?'S|", "eoD nhoJ^44@", &pw));
+	/* Similar to the old password */
+	BBUNIT_ASSERT_NOTNULL(obscure_msg("Ad4#21?'S|", "d4#21?'S", &pw));
+	/* adjacent letters */
+	BBUNIT_ASSERT_NOTNULL(obscure_msg("Ad4#21?'S|", "qwerty123", &pw));
+	/* Many similar chars */
+	BBUNIT_ASSERT_NOTNULL(obscure_msg("Ad4#21?'S|", "^33Daaaaaa1", &pw));
+
+	BBUNIT_ENDTEST;
+}
+
+BBUNIT_DEFINE_TEST(obscure_strong_pass)
+{
+	BBUNIT_ASSERT_NULL(obscure_msg("Rt4##2&:'|", "}(^#rrSX3S*22", &pw));
+
+	BBUNIT_ENDTEST;
+}
+
+#endif /* ENABLE_UNIT_TEST */

libbb/strrstr.c

@@ -7,13 +7,7 @@
  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
 
-#ifdef __DO_STRRSTR_TEST
-#include <stdlib.h>
-#include <string.h>
-#include <stdio.h>
-#else
 #include "libbb.h"
-#endif
 
 /*
  * The strrstr() function finds the last occurrence of the substring needle
@@ -34,8 +28,9 @@ char* FAST_FUNC strrstr(const char *haystack, const char *needle)
 	}
 }
 
-#ifdef __DO_STRRSTR_TEST
-int main(int argc, char **argv)
+#if ENABLE_UNIT_TEST
+
+BBUNIT_DEFINE_TEST(strrstr)
 {
 	static const struct {
 		const char *h, *n;
@@ -59,13 +54,13 @@ int main(int argc, char **argv)
 	i = 0;
 	while (i < sizeof(test_array) / sizeof(test_array[0])) {
 		const char *r = strrstr(test_array[i].h, test_array[i].n);
-		printf("'%s' vs. '%s': '%s' - ", test_array[i].h, test_array[i].n, r);
 		if (r == NULL)
 			r = test_array[i].h - 1;
-		printf("%s\n", r == test_array[i].h + test_array[i].pos ? "PASSED" : "FAILED");
+		BBUNIT_ASSERT_EQ(r, test_array[i].h + test_array[i].pos);
 		i++;
 	}
 
-	return 0;
+	BBUNIT_ENDTEST;
 }
-#endif
+
+#endif /* ENABLE_UNIT_TEST */