Commit 8c4905b9 authored by Stanislav Fomichev's avatar Stanislav Fomichev Committed by Daniel Borkmann
Browse files

libbpf: make sure bpf headers are c++ include-able



Wrap headers in extern "C", to turn off C++ mangling.
This simplifies including libbpf in c++ and linking against it.

v2 changes:
* do the same for btf.h

v3 changes:
* test_libbpf.cpp to test for possible future c++ breakages

Signed-off-by: default avatarStanislav Fomichev <sdf@google.com>
Acked-by: default avatarAlexei Starovoitov <ast@kernel.org>
Signed-off-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
parent 462c124c
......@@ -66,7 +66,7 @@ ifndef VERBOSE
endif
FEATURE_USER = .libbpf
FEATURE_TESTS = libelf libelf-mmap bpf reallocarray
FEATURE_TESTS = libelf libelf-mmap bpf reallocarray cxx
FEATURE_DISPLAY = libelf bpf
INCLUDES = -I. -I$(srctree)/tools/include -I$(srctree)/tools/arch/$(ARCH)/include/uapi -I$(srctree)/tools/include/uapi
......@@ -148,6 +148,12 @@ LIB_FILE := $(addprefix $(OUTPUT),$(LIB_FILE))
CMD_TARGETS = $(LIB_FILE)
CXX_TEST_TARGET = $(OUTPUT)test_libbpf
ifeq ($(feature-cxx), 1)
CMD_TARGETS += $(CXX_TEST_TARGET)
endif
TARGETS = $(CMD_TARGETS)
all: fixdep all_cmd
......@@ -175,6 +181,9 @@ $(OUTPUT)libbpf.so: $(BPF_IN)
$(OUTPUT)libbpf.a: $(BPF_IN)
$(QUIET_LINK)$(RM) $@; $(AR) rcs $@ $^
$(OUTPUT)test_libbpf: test_libbpf.cpp $(OUTPUT)libbpf.a
$(QUIET_LINK)$(CXX) $^ -lelf -o $@
define do_install
if [ ! -d '$(DESTDIR_SQ)$2' ]; then \
$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$2'; \
......@@ -201,8 +210,8 @@ config-clean:
$(Q)$(MAKE) -C $(srctree)/tools/build/feature/ clean >/dev/null
clean:
$(call QUIET_CLEAN, libbpf) $(RM) *.o *~ $(TARGETS) *.a *.so .*.d .*.cmd \
$(RM) LIBBPF-CFLAGS
$(call QUIET_CLEAN, libbpf) $(RM) $(TARGETS) $(CXX_TEST_TARGET) \
*.o *~ *.a *.so .*.d .*.cmd LIBBPF-CFLAGS
$(call QUIET_CLEAN, core-gen) $(RM) $(OUTPUT)FEATURE-DUMP.libbpf
......
......@@ -27,6 +27,10 @@
#include <stdbool.h>
#include <stddef.h>
#ifdef __cplusplus
extern "C" {
#endif
#ifndef LIBBPF_API
#define LIBBPF_API __attribute__((visibility("default")))
#endif
......@@ -132,4 +136,9 @@ LIBBPF_API int bpf_load_btf(void *btf, __u32 btf_size, char *log_buf,
LIBBPF_API int bpf_task_fd_query(int pid, int fd, __u32 flags, char *buf,
__u32 *buf_len, __u32 *prog_id, __u32 *fd_type,
__u64 *probe_offset, __u64 *probe_addr);
#ifdef __cplusplus
} /* extern "C" */
#endif
#endif /* __LIBBPF_BPF_H */
......@@ -6,6 +6,10 @@
#include <linux/types.h>
#ifdef __cplusplus
extern "C" {
#endif
#ifndef LIBBPF_API
#define LIBBPF_API __attribute__((visibility("default")))
#endif
......@@ -80,4 +84,8 @@ int btf_ext__reloc(struct btf *btf, struct btf_ext *btf_ext,
const char *sec_name, __u32 insns_cnt, void **func_info,
__u32 *func_info_len);
#ifdef __cplusplus
} /* extern "C" */
#endif
#endif /* __LIBBPF_BTF_H */
......@@ -16,6 +16,10 @@
#include <sys/types.h> // for size_t
#include <linux/bpf.h>
#ifdef __cplusplus
extern "C" {
#endif
#ifndef LIBBPF_API
#define LIBBPF_API __attribute__((visibility("default")))
#endif
......@@ -335,4 +339,9 @@ int libbpf_nl_get_qdisc(int sock, unsigned int nl_pid, int ifindex,
libbpf_dump_nlmsg_t dump_qdisc_nlmsg, void *cookie);
int libbpf_nl_get_filter(int sock, unsigned int nl_pid, int ifindex, int handle,
libbpf_dump_nlmsg_t dump_filter_nlmsg, void *cookie);
#ifdef __cplusplus
} /* extern "C" */
#endif
#endif /* __LIBBPF_LIBBPF_H */
/* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
#include "libbpf.h"
#include "bpf.h"
#include "btf.h"
/* do nothing, just make sure we can link successfully */
int main(int argc, char *argv[])
{
/* libbpf.h */
libbpf_set_print(NULL, NULL, NULL);
/* bpf.h */
bpf_prog_get_fd_by_id(0);
/* btf.h */
btf__new(NULL, 0, NULL);
}
Supports Markdown
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment