1# SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause)
2# Most of this file is copied from tools/lib/traceevent/Makefile
3
4RM ?= rm
5srctree := $(realpath $(srctree))
6
7VERSION_SCRIPT := libbpf.map
8LIBBPF_VERSION := $(shell \
9	grep -oE '^LIBBPF_([0-9.]+)' $(VERSION_SCRIPT) | \
10	sort -rV | head -n1 | cut -d'_' -f2)
11LIBBPF_MAJOR_VERSION := $(word 1,$(subst ., ,$(LIBBPF_VERSION)))
12LIBBPF_MINOR_VERSION := $(word 2,$(subst ., ,$(LIBBPF_VERSION)))
13
14MAKEFLAGS += --no-print-directory
15
16# This will work when bpf is built in tools env. where srctree
17# isn't set and when invoked from selftests build, where srctree
18# is a ".". building_out_of_srctree is undefined for in srctree
19# builds
20ifndef building_out_of_srctree
21srctree := $(patsubst %/,%,$(dir $(CURDIR)))
22srctree := $(patsubst %/,%,$(dir $(srctree)))
23srctree := $(patsubst %/,%,$(dir $(srctree)))
24#$(info Determined 'srctree' to be $(srctree))
25endif
26
27INSTALL = install
28
29# Use DESTDIR for installing into a different root directory.
30# This is useful for building a package. The program will be
31# installed in this directory as if it was the root directory.
32# Then the build tool can move it later.
33DESTDIR ?=
34DESTDIR_SQ = '$(subst ','\'',$(DESTDIR))'
35
36include $(srctree)/tools/scripts/Makefile.arch
37
38ifeq ($(LP64), 1)
39  libdir_relative = lib64
40else
41  libdir_relative = lib
42endif
43
44prefix ?= /usr/local
45libdir = $(prefix)/$(libdir_relative)
46man_dir = $(prefix)/share/man
47man_dir_SQ = '$(subst ','\'',$(man_dir))'
48
49export man_dir man_dir_SQ INSTALL
50export DESTDIR DESTDIR_SQ
51
52include $(srctree)/tools/scripts/Makefile.include
53
54# copy a bit from Linux kbuild
55
56ifeq ("$(origin V)", "command line")
57  VERBOSE = $(V)
58endif
59ifndef VERBOSE
60  VERBOSE = 0
61endif
62
63INCLUDES = -I$(or $(OUTPUT),.) \
64	   -I$(srctree)/tools/include -I$(srctree)/tools/include/uapi
65
66export prefix libdir src obj
67
68# Shell quotes
69libdir_SQ = $(subst ','\'',$(libdir))
70libdir_relative_SQ = $(subst ','\'',$(libdir_relative))
71
72OBJ		= $@
73N		=
74
75LIB_TARGET	= libbpf.a libbpf.so.$(LIBBPF_VERSION)
76LIB_FILE	= libbpf.a libbpf.so*
77PC_FILE		= libbpf.pc
78
79# Set compile option CFLAGS
80ifdef EXTRA_CFLAGS
81  CFLAGS := $(EXTRA_CFLAGS)
82else
83  CFLAGS := -g -O2
84endif
85
86# Append required CFLAGS
87override CFLAGS += -std=gnu89
88override CFLAGS += $(EXTRA_WARNINGS) -Wno-switch-enum
89override CFLAGS += -Werror -Wall
90override CFLAGS += $(INCLUDES)
91override CFLAGS += -fvisibility=hidden
92override CFLAGS += -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64
93override CFLAGS += $(CLANG_CROSS_FLAGS)
94
95# flags specific for shared library
96SHLIB_FLAGS := -DSHARED -fPIC
97
98ifeq ($(VERBOSE),1)
99  Q =
100else
101  Q = @
102endif
103
104# Disable command line variables (CFLAGS) override from top
105# level Makefile (perf), otherwise build Makefile will get
106# the same command line setup.
107MAKEOVERRIDES=
108
109all:
110
111export srctree OUTPUT CC LD CFLAGS V
112include $(srctree)/tools/build/Makefile.include
113
114SHARED_OBJDIR	:= $(OUTPUT)sharedobjs/
115STATIC_OBJDIR	:= $(OUTPUT)staticobjs/
116BPF_IN_SHARED	:= $(SHARED_OBJDIR)libbpf-in.o
117BPF_IN_STATIC	:= $(STATIC_OBJDIR)libbpf-in.o
118BPF_HELPER_DEFS	:= $(OUTPUT)bpf_helper_defs.h
119BPF_GENERATED	:= $(BPF_HELPER_DEFS)
120
121LIB_TARGET	:= $(addprefix $(OUTPUT),$(LIB_TARGET))
122LIB_FILE	:= $(addprefix $(OUTPUT),$(LIB_FILE))
123PC_FILE		:= $(addprefix $(OUTPUT),$(PC_FILE))
124
125TAGS_PROG := $(if $(shell which etags 2>/dev/null),etags,ctags)
126
127GLOBAL_SYM_COUNT = $(shell readelf -s --wide $(BPF_IN_SHARED) | \
128			   cut -d "@" -f1 | sed 's/_v[0-9]_[0-9]_[0-9].*//' | \
129			   sed 's/\[.*\]//' | \
130			   awk '/GLOBAL/ && /DEFAULT/ && !/UND|ABS/ {print $$NF}' | \
131			   sort -u | wc -l)
132VERSIONED_SYM_COUNT = $(shell readelf --dyn-syms --wide $(OUTPUT)libbpf.so | \
133			      sed 's/\[.*\]//' | \
134			      awk '/GLOBAL/ && /DEFAULT/ && !/UND|ABS/ {print $$NF}' | \
135			      grep -Eo '[^ ]+@LIBBPF_' | cut -d@ -f1 | sort -u | wc -l)
136
137CMD_TARGETS = $(LIB_TARGET) $(PC_FILE)
138
139all: fixdep
140	$(Q)$(MAKE) all_cmd
141
142all_cmd: $(CMD_TARGETS) check
143
144$(BPF_IN_SHARED): force $(BPF_GENERATED)
145	@(test -f ../../include/uapi/linux/bpf.h -a -f ../../../include/uapi/linux/bpf.h && ( \
146	(diff -B ../../include/uapi/linux/bpf.h ../../../include/uapi/linux/bpf.h >/dev/null) || \
147	echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/bpf.h' differs from latest version at 'include/uapi/linux/bpf.h'" >&2 )) || true
148	@(test -f ../../include/uapi/linux/bpf_common.h -a -f ../../../include/uapi/linux/bpf_common.h && ( \
149	(diff -B ../../include/uapi/linux/bpf_common.h ../../../include/uapi/linux/bpf_common.h >/dev/null) || \
150	echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/bpf_common.h' differs from latest version at 'include/uapi/linux/bpf_common.h'" >&2 )) || true
151	@(test -f ../../include/uapi/linux/if_xdp.h -a -f ../../../include/uapi/linux/if_xdp.h && ( \
152	(diff -B ../../include/uapi/linux/if_xdp.h ../../../include/uapi/linux/if_xdp.h >/dev/null) || \
153	echo "Warning: Kernel ABI header at 'tools/include/uapi/linux/if_xdp.h' differs from latest version at 'include/uapi/linux/if_xdp.h'" >&2 )) || true
154	$(Q)$(MAKE) $(build)=libbpf OUTPUT=$(SHARED_OBJDIR) CFLAGS="$(CFLAGS) $(SHLIB_FLAGS)"
155
156$(BPF_IN_STATIC): force $(BPF_GENERATED)
157	$(Q)$(MAKE) $(build)=libbpf OUTPUT=$(STATIC_OBJDIR)
158
159$(BPF_HELPER_DEFS): $(srctree)/tools/include/uapi/linux/bpf.h
160	$(QUIET_GEN)$(srctree)/scripts/bpf_doc.py --header \
161		--file $(srctree)/tools/include/uapi/linux/bpf.h > $(BPF_HELPER_DEFS)
162
163$(OUTPUT)libbpf.so: $(OUTPUT)libbpf.so.$(LIBBPF_VERSION)
164
165$(OUTPUT)libbpf.so.$(LIBBPF_VERSION): $(BPF_IN_SHARED) $(VERSION_SCRIPT)
166	$(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) \
167		--shared -Wl,-soname,libbpf.so.$(LIBBPF_MAJOR_VERSION) \
168		-Wl,--version-script=$(VERSION_SCRIPT) $< -lelf -lz -o $@
169	@ln -sf $(@F) $(OUTPUT)libbpf.so
170	@ln -sf $(@F) $(OUTPUT)libbpf.so.$(LIBBPF_MAJOR_VERSION)
171
172$(OUTPUT)libbpf.a: $(BPF_IN_STATIC)
173	$(QUIET_LINK)$(RM) -f $@; $(AR) rcs $@ $^
174
175$(OUTPUT)libbpf.pc:
176	$(QUIET_GEN)sed -e "s|@PREFIX@|$(prefix)|" \
177		-e "s|@LIBDIR@|$(libdir_SQ)|" \
178		-e "s|@VERSION@|$(LIBBPF_VERSION)|" \
179		< libbpf.pc.template > $@
180
181check: check_abi check_version
182
183check_abi: $(OUTPUT)libbpf.so $(VERSION_SCRIPT)
184	@if [ "$(GLOBAL_SYM_COUNT)" != "$(VERSIONED_SYM_COUNT)" ]; then	 \
185		echo "Warning: Num of global symbols in $(BPF_IN_SHARED)"	 \
186		     "($(GLOBAL_SYM_COUNT)) does NOT match with num of"	 \
187		     "versioned symbols in $^ ($(VERSIONED_SYM_COUNT))." \
188		     "Please make sure all LIBBPF_API symbols are"	 \
189		     "versioned in $(VERSION_SCRIPT)." >&2;		 \
190		readelf -s --wide $(BPF_IN_SHARED) |			 \
191		    cut -d "@" -f1 | sed 's/_v[0-9]_[0-9]_[0-9].*//' |	 \
192		    sed 's/\[.*\]//' |					 \
193		    awk '/GLOBAL/ && /DEFAULT/ && !/UND/ {print $$NF}'|  \
194		    sort -u > $(OUTPUT)libbpf_global_syms.tmp;		 \
195		readelf --dyn-syms --wide $(OUTPUT)libbpf.so |		 \
196		    sed 's/\[.*\]//' |					 \
197		    awk '/GLOBAL/ && /DEFAULT/ && !/UND|ABS/ {print $$NF}'|  \
198		    grep -Eo '[^ ]+@LIBBPF_' | cut -d@ -f1 |		 \
199		    sort -u > $(OUTPUT)libbpf_versioned_syms.tmp; 	 \
200		diff -u $(OUTPUT)libbpf_global_syms.tmp			 \
201		     $(OUTPUT)libbpf_versioned_syms.tmp;		 \
202		rm $(OUTPUT)libbpf_global_syms.tmp			 \
203		   $(OUTPUT)libbpf_versioned_syms.tmp;			 \
204		exit 1;							 \
205	fi
206
207HDR_MAJ_VERSION := $(shell grep -oE '^$(pound)define LIBBPF_MAJOR_VERSION ([0-9]+)$$' libbpf_version.h | cut -d' ' -f3)
208HDR_MIN_VERSION := $(shell grep -oE '^$(pound)define LIBBPF_MINOR_VERSION ([0-9]+)$$' libbpf_version.h | cut -d' ' -f3)
209
210check_version: $(VERSION_SCRIPT) libbpf_version.h
211	@if [ "$(HDR_MAJ_VERSION)" != "$(LIBBPF_MAJOR_VERSION)" ]; then        \
212		echo "Error: libbpf major version mismatch detected: "	       \
213		     "'$(HDR_MAJ_VERSION)' != '$(LIBBPF_MAJOR_VERSION)'" >&2;  \
214		exit 1;							       \
215	fi
216	@if [ "$(HDR_MIN_VERSION)" != "$(LIBBPF_MINOR_VERSION)" ]; then	       \
217		echo "Error: libbpf minor version mismatch detected: "	       \
218		     "'$(HDR_MIN_VERSION)' != '$(LIBBPF_MINOR_VERSION)'" >&2;  \
219		exit 1;							       \
220	fi
221
222define do_install_mkdir
223	if [ ! -d '$(DESTDIR_SQ)$1' ]; then		\
224		$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$1';	\
225	fi
226endef
227
228define do_install
229	if [ ! -d '$(DESTDIR_SQ)$2' ]; then		\
230		$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$2';	\
231	fi;						\
232	$(INSTALL) $(if $3,-m $3,) $1 '$(DESTDIR_SQ)$2'
233endef
234
235install_lib: all_cmd
236	$(call QUIET_INSTALL, $(LIB_TARGET)) \
237		$(call do_install_mkdir,$(libdir_SQ)); \
238		cp -fpR $(LIB_FILE) $(DESTDIR)$(libdir_SQ)
239
240SRC_HDRS := bpf.h libbpf.h btf.h libbpf_common.h libbpf_legacy.h	     \
241	    bpf_helpers.h bpf_tracing.h bpf_endian.h bpf_core_read.h	     \
242	    skel_internal.h libbpf_version.h usdt.bpf.h
243GEN_HDRS := $(BPF_GENERATED)
244
245INSTALL_PFX := $(DESTDIR)$(prefix)/include/bpf
246INSTALL_SRC_HDRS := $(addprefix $(INSTALL_PFX)/, $(SRC_HDRS))
247INSTALL_GEN_HDRS := $(addprefix $(INSTALL_PFX)/, $(notdir $(GEN_HDRS)))
248
249$(INSTALL_SRC_HDRS): $(INSTALL_PFX)/%.h: %.h
250	$(call QUIET_INSTALL, $@) \
251		$(call do_install,$<,$(prefix)/include/bpf,644)
252
253$(INSTALL_GEN_HDRS): $(INSTALL_PFX)/%.h: $(OUTPUT)%.h
254	$(call QUIET_INSTALL, $@) \
255		$(call do_install,$<,$(prefix)/include/bpf,644)
256
257install_headers: $(BPF_GENERATED) $(INSTALL_SRC_HDRS) $(INSTALL_GEN_HDRS)
258	$(call QUIET_INSTALL, libbpf_headers)
259
260install_pkgconfig: $(PC_FILE)
261	$(call QUIET_INSTALL, $(PC_FILE)) \
262		$(call do_install,$(PC_FILE),$(libdir_SQ)/pkgconfig,644)
263
264install: install_lib install_pkgconfig install_headers
265
266clean:
267	$(call QUIET_CLEAN, libbpf) $(RM) -rf $(CMD_TARGETS)		     \
268		*~ .*.d .*.cmd LIBBPF-CFLAGS $(BPF_GENERATED)		     \
269		$(SHARED_OBJDIR) $(STATIC_OBJDIR)			     \
270		$(addprefix $(OUTPUT),					     \
271			    *.o *.a *.so *.so.$(LIBBPF_MAJOR_VERSION) *.pc)
272
273PHONY += force cscope tags check check_abi check_version
274force:
275
276cscope:
277	ls *.c *.h > cscope.files
278	cscope -b -q -I $(srctree)/include -f cscope.out
279
280tags:
281	$(RM) -f TAGS tags
282	ls *.c *.h | xargs $(TAGS_PROG) -a
283
284# Declare the contents of the .PHONY variable as phony.  We keep that
285# information in a variable so we can use it in if_changed and friends.
286.PHONY: $(PHONY)
287
288# Delete partially updated (corrupted) files on error
289.DELETE_ON_ERROR:
290
291help:
292	@echo 'libbpf common targets:'
293	@echo '  HINT: use "V=1" to enable verbose build'
294	@echo '  all     - build libraries and pkgconfig'
295	@echo '  clean   - remove all generated files'
296	@echo '  check   - check ABI and version info'
297	@echo ''
298	@echo 'libbpf install targets:'
299	@echo '  HINT: use "prefix"(defaults to "/usr/local") or "DESTDIR" (defaults to "/")'
300	@echo '        to adjust target destination, e.g. "make prefix=/usr/local install"'
301	@echo '  install          - build and install all headers, libraries and pkgconfig'
302	@echo '  install_headers  - install only headers to include/bpf'
303	@echo ''
304	@echo 'libbpf make targets:'
305	@echo '  tags    - use ctags to make tag information for source code browsing'
306	@echo '  cscope  - use cscope to make interactive source code browsing database'
307