linux/tools/bpf
Andrii Nakryiko bb8ffe61ea bpftool: Add C++-specific open/load/etc skeleton wrappers
Add C++-specific static methods for code-generated BPF skeleton for each
skeleton operation: open, open_opts, open_and_load, load, attach,
detach, destroy, and elf_bytes. This is to facilitate easier C++
templating on top of pure C BPF skeleton.

In C, open/load/destroy/etc "methods" are of the form
<skeleton_name>__<method>() to avoid name collision with similar
"methods" of other skeletons withint the same application. This works
well, but is very inconvenient for C++ applications that would like to
write generic (templated) wrappers around BPF skeleton to fit in with
C++ code base and take advantage of destructors and other convenient C++
constructs.

This patch makes it easier to build such generic templated wrappers by
additionally defining C++ static methods for skeleton's struct with
fixed names. This allows to refer to, say, open method as `T::open()`
instead of having to somehow generate `T__open()` function call.

Next patch adds an example template to test_cpp selftest to demonstrate
how it's possible to have all the operations wrapped in a generic
Skeleton<my_skeleton> type without explicitly passing function references.

An example of generated declaration section without %1$s placeholders:

  #ifdef __cplusplus
      static struct test_attach_probe *open(const struct bpf_object_open_opts *opts = nullptr);
      static struct test_attach_probe *open_and_load();
      static int load(struct test_attach_probe *skel);
      static int attach(struct test_attach_probe *skel);
      static void detach(struct test_attach_probe *skel);
      static void destroy(struct test_attach_probe *skel);
      static const void *elf_bytes(size_t *sz);
  #endif /* __cplusplus */

Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20220212055733.539056-2-andrii@kernel.org
2022-02-15 09:59:01 -08:00
..
bpftool bpftool: Add C++-specific open/load/etc skeleton wrappers 2022-02-15 09:59:01 -08:00
resolve_btfids Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2022-02-03 17:36:16 -08:00
runqslower tools/bpf: Rename 'struct event' to avoid naming conflict 2022-01-15 12:21:25 +11:00
.gitignore .gitignore: add SPDX License Identifier 2020-03-25 11:50:48 +01:00
bpf_asm.c docs: networking: convert filter.txt to ReST 2020-04-28 14:39:46 -07:00
bpf_dbg.c bpf: Simplify the calculation of variables 2021-03-04 19:24:53 -08:00
bpf_exp.l bpf: fix cbpf parser bug for octal numbers 2018-06-03 07:46:55 -07:00
bpf_exp.y tools, bpf_asm: Exit non-zero on errors 2021-02-26 22:53:50 +01:00
bpf_jit_disasm.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 232 2019-06-19 17:09:06 +02:00
Makefile tools: bpf: Fix error in 'make -C tools/ bpf_install' 2021-07-07 14:06:38 -07:00