Add canonical #ifndef/#define/#endif guard for generated vmlinux.h header with
__VMLINUX_H__ symbol. __VMLINUX_H__ is also going to play double role of
identifying whether vmlinux.h is being used, versus, say, BCC or non-CO-RE
libbpf modes with dependency on kernel headers. This will make it possible to
write helper macro/functions, agnostic to exact BPF program set up.
Signed-off-by: Andrii Nakryiko <andriin@xxxxxx>
---
tools/bpf/bpftool/btf.c | 5 +++++
1 file changed, 5 insertions(+)
diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c
index b3745ed711ba..bcaf55b59498 100644
--- a/tools/bpf/bpftool/btf.c
+++ b/tools/bpf/bpftool/btf.c
@@ -389,6 +389,9 @@ static int dump_btf_c(const struct btf *btf,
if (IS_ERR(d))
return PTR_ERR(d);
+ printf("#ifndef __VMLINUX_H__\n");
+ printf("#define __VMLINUX_H__\n");
+ printf("\n");
printf("#ifndef BPF_NO_PRESERVE_ACCESS_INDEX\n");
printf("#pragma clang attribute push (__attribute__((preserve_access_index)), apply_to = record)\n");
printf("#endif\n\n");
@@ -412,6 +415,8 @@ static int dump_btf_c(const struct btf *btf,
printf("#ifndef BPF_NO_PRESERVE_ACCESS_INDEX\n");
printf("#pragma clang attribute pop\n");
printf("#endif\n");
+ printf("\n");
+ printf("#endif /* __VMLINUX_H__ */\n");
done:
btf_dump__free(d);
--
2.17.1
