trace: Add active reference tracking

This WPA_TRACE=y additions allows components to register active references
to memory that has been provided to them as a pointer. If such an actively
referenced memory area is freed, tracer will report this as an error and
backtraces of both the invalid free and the location where this pointer
was marked referenced are shown.

1 files changed, 23 insertions, 0 deletions

diff --git a/src/utils/trace.h b/src/utils/trace.h
index 8074d25..009b6e3 100644
--- a/src/utils/trace.h
+++ b/src/utils/trace.h
@@ -20,20 +20,43 @@
 #ifdef WPA_TRACE
 #include <execinfo.h>
 
+#include "list.h"
+
 #define WPA_TRACE_INFO void *btrace[WPA_TRACE_LEN]; int btrace_num;
+
+struct wpa_trace_ref {
+	struct dl_list list;
+	const void *addr;
+	WPA_TRACE_INFO
+};
+#define WPA_TRACE_REF(name) struct wpa_trace_ref wpa_trace_ref_##name
+
 #define wpa_trace_dump(title, ptr) \
 	wpa_trace_dump_func((title), (ptr)->btrace, (ptr)->btrace_num)
 void wpa_trace_dump_func(const char *title, void **btrace, int btrace_num);
 #define wpa_trace_record(ptr) \
 	(ptr)->btrace_num = backtrace((ptr)->btrace, WPA_TRACE_LEN)
 void wpa_trace_show(const char *title);
+#define wpa_trace_add_ref(ptr, name, addr) \
+	wpa_trace_add_ref_func(&(ptr)->wpa_trace_ref_##name, (addr))
+void wpa_trace_add_ref_func(struct wpa_trace_ref *ref, const void *addr);
+#define wpa_trace_remove_ref(ptr, name, addr)	\
+	do { \
+		if ((addr)) \
+			dl_list_del(&(ptr)->wpa_trace_ref_##name.list); \
+	} while (0)
+void wpa_trace_check_ref(const void *addr);
 
 #else /* WPA_TRACE */
 
 #define WPA_TRACE_INFO
+#define WPA_TRACE_REF(n)
 #define wpa_trace_dump(title, ptr) do { } while (0)
 #define wpa_trace_record(ptr) do { } while (0)
 #define wpa_trace_show(title) do { } while (0)
+#define wpa_trace_add_ref(ptr, name, addr) do { } while (0)
+#define wpa_trace_remove_ref(ptr, name, addr) do { } while (0)
+#define wpa_trace_check_ref(addr) do { } while (0)
 
 #endif /* WPA_TRACE */