bpftools: update, split off bpftool and libbpf packages

My original bpftools package made "variant" builds of bpftool and libbpf
as a convenience, since both used the same local kernel sources with the
same versioning. This is no longer the case, since the commit below
switched to using an out-of-tree build mirror hosting repos for each.

Replace bpftools with separate bpftool and libbpf packages, each simplified
and correctly versioned. Also fix the broken libbpf ABI introduced in the
same commit. Existing build .config files are not impacted.

Fixes: 00cbf6f6ab ("bpftools: update to standalone bpftools + libbpf, use the latest version")
Signed-off-by: Tony Ambardar <itugrok@yahoo.com>
(cherry picked from commit afe1bf11f2)
Signed-off-by: Daniel Golle <daniel@makrotopia.org>

package/network/utils/bpftool/Makefile

@@ -0,0 +1,99 @@
+#
+# Copyright (C) 2020-2023 Tony Ambardar <itugrok@yahoo.com>
+#
+# This is free software, licensed under the GNU General Public License v2.
+# See /LICENSE for more information.
+#
+
+include $(TOPDIR)/rules.mk
+
+PKG_NAME:=bpftools
+PKG_VERSION:=7.2.0
+PKG_RELEASE:=1
+
+PKG_SOURCE_URL:=https://github.com/libbpf/bpftool
+PKG_SOURCE_PROTO:=git
+PKG_SOURCE_VERSION:=19ff0564980a7429e730f6987a0b0bf418b3c676
+PKG_MIRROR_HASH:=f9b9871f64986dd2e5dab7060bb919398256ba93964da49c62efaf0e6bc9bbc4
+
+PKG_MAINTAINER:=Tony Ambardar <itugrok@yahoo.com>
+
+PKG_BUILD_FLAGS:=no-mips16
+PKG_BUILD_PARALLEL:=1
+PKG_INSTALL:=1
+
+include $(INCLUDE_DIR)/package.mk
+include $(INCLUDE_DIR)/nls.mk
+
+define Package/bpftool/Default
+  SECTION:=net
+  CATEGORY:=Network
+  TITLE:=bpftool - eBPF subsystem utility
+  LICENSE:=GPL-2.0-only OR BSD-2-Clause
+  URL:=http://www.kernel.org
+  DEPENDS:=+libelf
+endef
+
+define Package/bpftool-minimal
+  $(call Package/bpftool/Default)
+  TITLE+= (Minimal)
+  VARIANT:=minimal
+  DEFAULT_VARIANT:=1
+  PROVIDES:=bpftool
+  ALTERNATIVES:=200:/usr/sbin/bpftool:/usr/libexec/bpftool-minimal
+endef
+
+define Package/bpftool-full
+  $(call Package/bpftool/Default)
+  TITLE+= (Full)
+  VARIANT:=full
+  PROVIDES:=bpftool
+  ALTERNATIVES:=300:/usr/sbin/bpftool:/usr/libexec/bpftool-full
+  DEPENDS+= +libbfd +libopcodes
+endef
+
+define Package/bpftool-minimal/description
+  A tool for inspection and simple manipulation of eBPF programs and maps.
+endef
+
+define Package/bpftool-full/description
+  A tool for inspection and simple manipulation of eBPF programs and maps.
+  This full version uses libbfd and libopcodes to support disassembly of
+  eBPF programs and jited code.
+endef
+
+TARGET_CFLAGS += -ffunction-sections -fdata-sections -flto
+TARGET_LDFLAGS += -Wl,--gc-sections -flto
+
+ifeq ($(BUILD_VARIANT),full)
+  full:=1
+else
+  full:=0
+endif
+
+MAKE_VARS = \
+	EXTRA_CFLAGS="$(TARGET_CFLAGS) $(TARGET_CPPFLAGS)" \
+	LDFLAGS="$(TARGET_LDFLAGS)"
+
+MAKE_FLAGS += \
+	OUTPUT="$(PKG_BUILD_DIR)/" \
+	prefix="/usr" \
+	$(if $(findstring c,$(OPENWRT_VERBOSE)),V=1,V='') \
+	check_feat=0 \
+	feature-clang-bpf-co-re=0 \
+	feature-libbfd=$(full) \
+	feature-llvm=0 \
+	feature-libcap=0 \
+	feature-disassembler-four-args=1 \
+	feature-disassembler-init-styled=1
+
+MAKE_PATH = src
+
+define Package/bpftool-$(BUILD_VARIANT)/install
+	$(INSTALL_DIR) $(1)/usr/libexec
+	$(INSTALL_BIN) $(PKG_INSTALL_DIR)/usr/sbin/bpftool \
+		$(1)/usr/libexec/bpftool-$(BUILD_VARIANT)
+endef
+
+$(eval $(call BuildPackage,bpftool-full))
+$(eval $(call BuildPackage,bpftool-minimal))

package/network/utils/bpftool/patches/001-cflags.patch

@@ -0,0 +1,10 @@
+--- a/libbpf/src/Makefile
++++ b/libbpf/src/Makefile
+@@ -34,6 +34,7 @@ ALL_CFLAGS := $(INCLUDES)
+ 
+ SHARED_CFLAGS += -fPIC -fvisibility=hidden -DSHARED
+ 
++CFLAGS = $(EXTRA_CFLAGS)
+ CFLAGS ?= -g -O2 -Werror -Wall -std=gnu89
+ ALL_CFLAGS += $(CFLAGS) -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 $(EXTRA_CFLAGS)
+ ALL_LDFLAGS += $(LDFLAGS) $(EXTRA_LDFLAGS)

package/network/utils/bpftool/patches/002-includes.patch

@@ -0,0 +1,26 @@
+--- a/libbpf/include/linux/list.h
++++ b/libbpf/include/linux/list.h
+@@ -3,6 +3,8 @@
+ #ifndef __LINUX_LIST_H
+ #define __LINUX_LIST_H
+ 
++#include <linux/types.h>
++
+ #define LIST_HEAD_INIT(name) { &(name), &(name) }
+ #define LIST_HEAD(name) \
+         struct list_head name = LIST_HEAD_INIT(name)
+--- a/src/Makefile
++++ b/src/Makefile
+@@ -73,10 +73,10 @@ CFLAGS += -W -Wall -Wextra -Wno-unused-p
+ CFLAGS += $(filter-out -Wswitch-enum -Wnested-externs,$(EXTRA_WARNINGS))
+ CFLAGS += -DPACKAGE='"bpftool"' -D__EXPORTED_HEADERS__ \
+ 	-I$(or $(OUTPUT),.) \
+-	-I$(LIBBPF_INCLUDE) \
+ 	-I$(srctree)/src/kernel/bpf/ \
+ 	-I$(srctree)/include \
+-	-I$(srctree)/include/uapi
++	-I$(srctree)/include/uapi \
++	-I$(LIBBPF_INCLUDE)
+ ifneq ($(BPFTOOL_VERSION),)
+ CFLAGS += -DBPFTOOL_VERSION='"$(BPFTOOL_VERSION)"'
+ endif