libbpf: Add helper macro to clear opts structs

Add a small and generic LIBBPF_OPTS_CLEAR() helper macros which clears an opts structure and reinitializes its .sz member to place the structure size. I found this very useful when developing selftests, but it is also generic enough as a macro next to the existing LIBBPF_OPTS() which hides the .sz initialization, too. Signed-off-by: Daniel Borkmann <[email protected]>
cilium · Jul 7, 2023 · 38127e9 · 38127e9
1 parent dbf28df
commit 38127e9
Showing 1 changed file with 11 additions and 0 deletions.
diff --git a/tools/lib/bpf/libbpf_common.h b/tools/lib/bpf/libbpf_common.h
@@ -70,4 +70,15 @@
 		};							    \
 	})
 
+/* Helper macro to clear a libbpf options struct
+ *
+ * Small helper macro to reset all fields and to reinitialize the common
+ * structure size member.
+ */
+#define LIBBPF_OPTS_CLEAR(NAME)						    \
+	do {								    \
+		memset(&NAME, 0, sizeof(NAME));				    \
+		NAME.sz = sizeof(NAME);					    \
+	} while (0)
+
 #endif /* __LIBBPF_LIBBPF_COMMON_H */