memblock tests: add verbose output to memblock tests

Add and use functions and macros for printing verbose testing output.

If the Memblock simulator was compiled with VERBOSE=1:
- prefix_push(): appends the given string to a prefix string that will be
  printed in test_fail() and test_pass*().

- prefix_pop(): removes the last prefix from the prefix string.

- prefix_reset(): clears the prefix string.

- test_fail(): prints a message after a test fails containing the test
  number of the failing test and the prefix.

- test_pass(): prints a message after a test passes containing its test
  number and the prefix.

- test_print(): prints the given formatted output string.

- test_pass_pop(): runs test_pass() followed by prefix_pop().

- PREFIX_PUSH(): runs prefix_push(__func__).

If the Memblock simulator was not compiled with VERBOSE=1, these
functions/macros do nothing.

Add the assert wrapper macros ASSERT_EQ(), ASSERT_NE(), and ASSERT_LT().
If the assert condition fails, these macros call test_fail() before
executing assert().

Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Shaoqin Huang <shaoqin.huang@intel.com>
Signed-off-by: Rebecca Mckeever <remckee0@gmail.com>
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Link: https://lore.kernel.org/r/f234d443fe154d5ae8d8aa07284aff69edfb6f61.1656907314.git.remckee0@gmail.com

tools/testing/memblock/tests/common.c

@@ -4,8 +4,12 @@
 
 #define INIT_MEMBLOCK_REGIONS			128
 #define INIT_MEMBLOCK_RESERVED_REGIONS		INIT_MEMBLOCK_REGIONS
+#define PREFIXES_MAX				15
+#define DELIM					": "
 
 static struct test_memory memory_block;
+static const char __maybe_unused *prefixes[PREFIXES_MAX];
+static int __maybe_unused nr_prefixes;
 
 void reset_memblock_regions(void)
 {
@@ -46,3 +50,56 @@ void dummy_physical_memory_cleanup(void)
 {
 	free(memory_block.base);
 }
+
+#ifdef VERBOSE
+void print_prefixes(const char *postfix)
+{
+	for (int i = 0; i < nr_prefixes; i++)
+		test_print("%s%s", prefixes[i], DELIM);
+	test_print(postfix);
+}
+
+void test_fail(void)
+{
+	ksft_test_result_fail(": ");
+	print_prefixes("failed\n");
+}
+
+void test_pass(void)
+{
+	ksft_test_result_pass(": ");
+	print_prefixes("passed\n");
+}
+
+void test_print(const char *fmt, ...)
+{
+	int saved_errno = errno;
+	va_list args;
+
+	va_start(args, fmt);
+	errno = saved_errno;
+	vprintf(fmt, args);
+	va_end(args);
+}
+
+void prefix_reset(void)
+{
+	memset(prefixes, 0, PREFIXES_MAX * sizeof(char *));
+	nr_prefixes = 0;
+}
+
+void prefix_push(const char *prefix)
+{
+	assert(nr_prefixes < PREFIXES_MAX);
+	prefixes[nr_prefixes] = prefix;
+	nr_prefixes++;
+}
+
+void prefix_pop(void)
+{
+	if (nr_prefixes > 0) {
+		prefixes[nr_prefixes - 1] = 0;
+		nr_prefixes--;
+	}
+}
+#endif /* VERBOSE */