On Mon, Jan 31, 2022 at 1:11 PM Quentin Monnet <quentin@xxxxxxxxxxxxx> wrote:
>
> To help users check what version of libbpf has been used to compile
> bpftool, embed the version number and print it along with bpftool's own
> version number.
>
> Signed-off-by: Quentin Monnet <quentin@xxxxxxxxxxxxx>
> ---
> tools/bpf/bpftool/Documentation/common_options.rst | 3 ++-
> tools/bpf/bpftool/Makefile | 2 ++
> tools/bpf/bpftool/main.c | 3 +++
> 3 files changed, 7 insertions(+), 1 deletion(-)
>
> diff --git a/tools/bpf/bpftool/Documentation/common_options.rst b/tools/bpf/bpftool/Documentation/common_options.rst
> index 908487b9c2ad..24166733d3ae 100644
> --- a/tools/bpf/bpftool/Documentation/common_options.rst
> +++ b/tools/bpf/bpftool/Documentation/common_options.rst
> @@ -4,7 +4,8 @@
> Print short help message (similar to **bpftool help**).
>
> -V, --version
> - Print version number (similar to **bpftool version**), and optional
> + Print bpftool's version number (similar to **bpftool version**), the
> + version of libbpf that was used to compile the binary, and optional
> features that were included when bpftool was compiled. Optional
> features include linking against libbfd to provide the disassembler
> for JIT-ted programs (**bpftool prog dump jited**) and usage of BPF
> diff --git a/tools/bpf/bpftool/Makefile b/tools/bpf/bpftool/Makefile
> index 83369f55df61..bd5a8cafac49 100644
> --- a/tools/bpf/bpftool/Makefile
> +++ b/tools/bpf/bpftool/Makefile
> @@ -42,6 +42,7 @@ LIBBPF_BOOTSTRAP_INTERNAL_HDRS := $(addprefix $(LIBBPF_BOOTSTRAP_HDRS_DIR)/,hash
> ifeq ($(BPFTOOL_VERSION),)
> BPFTOOL_VERSION := $(shell make -rR --no-print-directory -sC ../../.. kernelversion)
> endif
> +LIBBPF_VERSION := $(shell make -r --no-print-directory -sC $(BPF_DIR) libbpfversion)
>
why can't you use libbpf_version_string() API instead?
> $(LIBBPF_OUTPUT) $(BOOTSTRAP_OUTPUT) $(LIBBPF_BOOTSTRAP_OUTPUT) $(LIBBPF_HDRS_DIR) $(LIBBPF_BOOTSTRAP_HDRS_DIR):
> $(QUIET_MKDIR)mkdir -p $@
> @@ -84,6 +85,7 @@ CFLAGS += -DPACKAGE='"bpftool"' -D__EXPORTED_HEADERS__ \
> -I$(srctree)/tools/include \
> -I$(srctree)/tools/include/uapi
> CFLAGS += -DBPFTOOL_VERSION='"$(BPFTOOL_VERSION)"'
> +CFLAGS += -DLIBBPF_VERSION='"$(LIBBPF_VERSION)"'
> ifneq ($(EXTRA_CFLAGS),)
> CFLAGS += $(EXTRA_CFLAGS)
> endif
> diff --git a/tools/bpf/bpftool/main.c b/tools/bpf/bpftool/main.c
> index 9d01fa9de033..4bda73057980 100644
> --- a/tools/bpf/bpftool/main.c
> +++ b/tools/bpf/bpftool/main.c
> @@ -89,6 +89,8 @@ static int do_version(int argc, char **argv)
>
> jsonw_name(json_wtr, "version");
> jsonw_printf(json_wtr, "\"%s\"", BPFTOOL_VERSION);
> + jsonw_name(json_wtr, "libbpf_version");
> + jsonw_printf(json_wtr, "\"%s\"", LIBBPF_VERSION);
>
> jsonw_name(json_wtr, "features");
> jsonw_start_object(json_wtr); /* features */
> @@ -102,6 +104,7 @@ static int do_version(int argc, char **argv)
> unsigned int nb_features = 0;
>
> printf("%s v%s\n", bin_name, BPFTOOL_VERSION);
> + printf("using libbpf v%s\n", LIBBPF_VERSION);
> printf("features:");
> if (has_libbfd) {
> printf(" libbfd");
> --
> 2.32.0
>
