test: Add a basic traceback printer

Some tests have some complex flows, and it's useful to be able to see
the call path when there's a failure.

This patch adds a very simple traceback printer, along with changing the
test build arguments to include more debug information.

The result you get from this traceback printer just gives you a function
name and the index into its .txt content, so to use it for more than
"which function calls which", you'll need to use eu-addr2line with the
output.

Signed-off-by: Peter Jones <pjones@redhat.com>

1 files changed, 26 insertions, 0 deletions

diff --git a/test.c b/test.c
index 81578c5a..d9902ebc 100644
--- a/test.c
+++ b/test.c
@@ -9,9 +9,35 @@
 #endif
 #include "shim.h"
 
+#include <execinfo.h>
+#include <stdio.h>
+#include <string.h>
+
+#define BT_BUF_SIZE (4096/sizeof(void *))
+
+static void *frames[BT_BUF_SIZE] = { 0, };
+
 UINT8 in_protocol = 0;
 int debug = DEFAULT_DEBUG_PRINT_STATE;
 
+void
+print_traceback(int skip)
+{
+	int nptrs;
+	char **strings;
+
+	nptrs = backtrace(frames, BT_BUF_SIZE);
+	if (nptrs < skip)
+		return;
+
+	strings = backtrace_symbols(frames, nptrs);
+	for (int i = skip; strings != NULL && i < nptrs; i++) {
+		printf("%p %s\n", (void *)frames[i], strings[i]);
+	}
+	if (strings)
+		free(strings);
+}
+
 #pragma GCC diagnostic ignored "-Wunused-parameter"
 #pragma GCC diagnostic ignored "-Wunused-function"