Andrii Nakryiko <andriin@xxxxxx> [Wed, 2019-08-14 13:57 -0700]:
> Currently libbpf version is specified in 2 places: libbpf.map and
> Makefile. They easily get out of sync and it's very easy to update one,
> but forget to update another one. In addition, Github projection of
> libbpf has to maintain its own version which has to be remembered to be
> kept in sync manually, which is very error-prone approach.
>
> This patch makes libbpf.map a source of truth for libbpf version and
> uses shell invocation to parse out correct full and major libbpf version
> to use during build. Now we need to make sure that once new release
> cycle starts, we need to add (initially) empty section to libbpf.map
> with correct latest version.
>
> This also will make it possible to keep Github projection consistent
> with kernel sources version of libbpf by adopting similar parsing of
> version from libbpf.map.
>
> v2->v3:
> - grep -o + sort -rV (Andrey);
>
> v1->v2:
> - eager version vars evaluation (Jakub);
> - simplified version regex (Andrey);
Acked-by: Andrey Ignatov <rdna@xxxxxx>
> Cc: Andrey Ignatov <rdna@xxxxxx>
> Signed-off-by: Andrii Nakryiko <andriin@xxxxxx>
> ---
> tools/lib/bpf/Makefile | 20 ++++++++------------
> tools/lib/bpf/libbpf.map | 3 +++
> 2 files changed, 11 insertions(+), 12 deletions(-)
>
> diff --git a/tools/lib/bpf/Makefile b/tools/lib/bpf/Makefile
> index 9312066a1ae3..148a27164189 100644
> --- a/tools/lib/bpf/Makefile
> +++ b/tools/lib/bpf/Makefile
> @@ -1,9 +1,10 @@
> # SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
> # Most of this file is copied from tools/lib/traceevent/Makefile
>
> -BPF_VERSION = 0
> -BPF_PATCHLEVEL = 0
> -BPF_EXTRAVERSION = 4
> +LIBBPF_VERSION := $(shell \
> + grep -oE '^LIBBPF_([0-9.]+)' libbpf.map | \
> + sort -rV | head -n1 | cut -d'_' -f2)
> +LIBBPF_MAJOR_VERSION := $(firstword $(subst ., ,$(LIBBPF_VERSION)))
>
> MAKEFLAGS += --no-print-directory
>
> @@ -79,15 +80,9 @@ export prefix libdir src obj
> libdir_SQ = $(subst ','\'',$(libdir))
> libdir_relative_SQ = $(subst ','\'',$(libdir_relative))
>
> -VERSION = $(BPF_VERSION)
> -PATCHLEVEL = $(BPF_PATCHLEVEL)
> -EXTRAVERSION = $(BPF_EXTRAVERSION)
> -
> OBJ = $@
> N =
>
> -LIBBPF_VERSION = $(BPF_VERSION).$(BPF_PATCHLEVEL).$(BPF_EXTRAVERSION)
> -
> LIB_TARGET = libbpf.a libbpf.so.$(LIBBPF_VERSION)
> LIB_FILE = libbpf.a libbpf.so*
> PC_FILE = libbpf.pc
> @@ -178,10 +173,10 @@ $(BPF_IN): force elfdep bpfdep
> $(OUTPUT)libbpf.so: $(OUTPUT)libbpf.so.$(LIBBPF_VERSION)
>
> $(OUTPUT)libbpf.so.$(LIBBPF_VERSION): $(BPF_IN)
> - $(QUIET_LINK)$(CC) --shared -Wl,-soname,libbpf.so.$(VERSION) \
> + $(QUIET_LINK)$(CC) --shared -Wl,-soname,libbpf.so.$(LIBBPF_MAJOR_VERSION) \
> -Wl,--version-script=$(VERSION_SCRIPT) $^ -lelf -o $@
> @ln -sf $(@F) $(OUTPUT)libbpf.so
> - @ln -sf $(@F) $(OUTPUT)libbpf.so.$(VERSION)
> + @ln -sf $(@F) $(OUTPUT)libbpf.so.$(LIBBPF_MAJOR_VERSION)
>
> $(OUTPUT)libbpf.a: $(BPF_IN)
> $(QUIET_LINK)$(RM) $@; $(AR) rcs $@ $^
> @@ -257,7 +252,8 @@ config-clean:
>
> clean:
> $(call QUIET_CLEAN, libbpf) $(RM) $(TARGETS) $(CXX_TEST_TARGET) \
> - *.o *~ *.a *.so *.so.$(VERSION) .*.d .*.cmd *.pc LIBBPF-CFLAGS
> + *.o *~ *.a *.so *.so.$(LIBBPF_MAJOR_VERSION) .*.d .*.cmd \
> + *.pc LIBBPF-CFLAGS
> $(call QUIET_CLEAN, core-gen) $(RM) $(OUTPUT)FEATURE-DUMP.libbpf
>
>
> diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
> index f9d316e873d8..4e72df8e98ba 100644
> --- a/tools/lib/bpf/libbpf.map
> +++ b/tools/lib/bpf/libbpf.map
> @@ -184,3 +184,6 @@ LIBBPF_0.0.4 {
> perf_buffer__new_raw;
> perf_buffer__poll;
> } LIBBPF_0.0.3;
> +
> +LIBBPF_0.0.5 {
> +} LIBBPF_0.0.4;
> --
> 2.17.1
>
--
Andrey Ignatov
