AF_XDP-interaction: Add btf_unit_test

Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>

AF_XDP-interaction/Makefile

@@ -1,6 +1,7 @@
 # SPDX-License-Identifier: (GPL-2.0 OR BSD-2-Clause)
 
 USER_TARGETS   := af_xdp_user
+USER_TARGETS   += btf_unit_test
 BPF_TARGETS    := af_xdp_kern
 
 # Define C-code objects USER_TARGETS needs

AF_XDP-interaction/btf_unit_test.c

@@ -0,0 +1,51 @@
+/* Code exercising BTF userspace decoding */
+
+#include <stddef.h>
+#include <stdlib.h>
+#include <stdio.h>
+
+#include <errno.h>
+
+#include <bpf/bpf.h>
+#include <bpf/libbpf.h>
+
+#include <bpf/btf.h> /* provided by libbpf */
+
+#include "lib_xsk_extend.h"
+
+/* Exit return codes - can be used by scripts looking at exit code */
+#define EXIT_OK             0 /* == EXIT_SUCCESS (stdlib.h) man exit(3) */
+#define EXIT_FAIL           1 /* == EXIT_FAILURE (stdlib.h) man exit(3) */
+#define EXIT_FAIL_OPTION    2
+#define EXIT_FAIL_XDP       3
+#define EXIT_FAIL_BPF       4
+#define EXIT_FAIL_BTF       5
+
+struct bpf_object *load_bpf_object() {
+	struct bpf_object *obj;
+	char buf[100];
+	int err;
+
+	obj = bpf_object__open_file("af_xdp_kern.o", NULL);
+	err = libbpf_get_error(obj);
+	if (err) {
+		libbpf_strerror(err, buf, sizeof(buf));
+		printf("Error opening file: %s\n", buf);
+		return NULL;
+	}
+	return obj;
+}
+
+int main(int argc, char **argv)
+{
+	struct bpf_object *bpf_obj;
+	// int err = 0;
+
+	bpf_obj = load_bpf_object();
+	if (!bpf_obj)
+		return EXIT_FAIL_BPF;
+
+	return EXIT_OK;
+}
+
+

AF_XDP-interaction/lib_xsk_extend.c

@@ -216,7 +216,7 @@ int xsk_btf__init_xdp_hint(struct btf *btf_obj,
 	if (err)
 		goto error_entry;
 
-	/* TODO: Validate 'btf_id' member is last member */
+	/* TODO: Validate 'btf_id' is last member */
 
 	return 0;