diff options
| -rw-r--r-- | tools/lib/bpf/btf.h | 51 | ||||
| -rw-r--r-- | tools/lib/bpf/btf_dump.c | 31 | ||||
| -rw-r--r-- | tools/lib/bpf/libbpf.map | 2 |
3 files changed, 71 insertions, 13 deletions
diff --git a/tools/lib/bpf/btf.h b/tools/lib/bpf/btf.h index 6aae4f62ee0b..45310c65e865 100644 --- a/tools/lib/bpf/btf.h +++ b/tools/lib/bpf/btf.h @@ -267,15 +267,58 @@ LIBBPF_API int btf__dedup_deprecated(struct btf *btf, struct btf_ext *btf_ext, c struct btf_dump; struct btf_dump_opts { - void *ctx; + union { + size_t sz; + void *ctx; /* DEPRECATED: will be gone in v1.0 */ + }; }; typedef void (*btf_dump_printf_fn_t)(void *ctx, const char *fmt, va_list args); LIBBPF_API struct btf_dump *btf_dump__new(const struct btf *btf, - const struct btf_ext *btf_ext, - const struct btf_dump_opts *opts, - btf_dump_printf_fn_t printf_fn); + btf_dump_printf_fn_t printf_fn, + void *ctx, + const struct btf_dump_opts *opts); + +LIBBPF_API struct btf_dump *btf_dump__new_v0_6_0(const struct btf *btf, + btf_dump_printf_fn_t printf_fn, + void *ctx, + const struct btf_dump_opts *opts); + +LIBBPF_API struct btf_dump *btf_dump__new_deprecated(const struct btf *btf, + const struct btf_ext *btf_ext, + const struct btf_dump_opts *opts, + btf_dump_printf_fn_t printf_fn); + +/* Choose either btf_dump__new() or btf_dump__new_deprecated() based on the + * type of 4th argument. If it's btf_dump's print callback, use deprecated + * API; otherwise, choose the new btf_dump__new(). ___libbpf_override() + * doesn't work here because both variants have 4 input arguments. + * + * (void *) casts are necessary to avoid compilation warnings about type + * mismatches, because even though __builtin_choose_expr() only ever evaluates + * one side the other side still has to satisfy type constraints (this is + * compiler implementation limitation which might be lifted eventually, + * according to the documentation). So passing struct btf_ext in place of + * btf_dump_printf_fn_t would be generating compilation warning. Casting to + * void * avoids this issue. + * + * Also, two type compatibility checks for a function and function pointer are + * required because passing function reference into btf_dump__new() as + * btf_dump__new(..., my_callback, ...) and as btf_dump__new(..., + * &my_callback, ...) (not explicit ampersand in the latter case) actually + * differs as far as __builtin_types_compatible_p() is concerned. Thus two + * checks are combined to detect callback argument. + * + * The rest works just like in case of ___libbpf_override() usage with symbol + * versioning. + */ +#define btf_dump__new(a1, a2, a3, a4) __builtin_choose_expr( \ + __builtin_types_compatible_p(typeof(a4), btf_dump_printf_fn_t) || \ + __builtin_types_compatible_p(typeof(a4), void(void *, const char *, va_list)), \ + btf_dump__new_deprecated((void *)a1, (void *)a2, (void *)a3, (void *)a4), \ + btf_dump__new((void *)a1, (void *)a2, (void *)a3, (void *)a4)) + LIBBPF_API void btf_dump__free(struct btf_dump *d); LIBBPF_API int btf_dump__dump_type(struct btf_dump *d, __u32 id); diff --git a/tools/lib/bpf/btf_dump.c b/tools/lib/bpf/btf_dump.c index 17db62b5002e..b8cd7e4f557a 100644 --- a/tools/lib/bpf/btf_dump.c +++ b/tools/lib/bpf/btf_dump.c @@ -77,9 +77,8 @@ struct btf_dump_data { struct btf_dump { const struct btf *btf; - const struct btf_ext *btf_ext; btf_dump_printf_fn_t printf_fn; - struct btf_dump_opts opts; + void *cb_ctx; int ptr_sz; bool strip_mods; bool skip_anon_defs; @@ -138,29 +137,32 @@ static void btf_dump_printf(const struct btf_dump *d, const char *fmt, ...) va_list args; va_start(args, fmt); - d->printf_fn(d->opts.ctx, fmt, args); + d->printf_fn(d->cb_ctx, fmt, args); va_end(args); } static int btf_dump_mark_referenced(struct btf_dump *d); static int btf_dump_resize(struct btf_dump *d); -struct btf_dump *btf_dump__new(const struct btf *btf, - const struct btf_ext *btf_ext, - const struct btf_dump_opts *opts, - btf_dump_printf_fn_t printf_fn) +DEFAULT_VERSION(btf_dump__new_v0_6_0, btf_dump__new, LIBBPF_0.6.0) +struct btf_dump *btf_dump__new_v0_6_0(const struct btf *btf, + btf_dump_printf_fn_t printf_fn, + void *ctx, + const struct btf_dump_opts *opts) { struct btf_dump *d; int err; + if (!printf_fn) + return libbpf_err_ptr(-EINVAL); + d = calloc(1, sizeof(struct btf_dump)); if (!d) return libbpf_err_ptr(-ENOMEM); d->btf = btf; - d->btf_ext = btf_ext; d->printf_fn = printf_fn; - d->opts.ctx = opts ? opts->ctx : NULL; + d->cb_ctx = ctx; d->ptr_sz = btf__pointer_size(btf) ? : sizeof(void *); d->type_names = hashmap__new(str_hash_fn, str_equal_fn, NULL); @@ -186,6 +188,17 @@ err: return libbpf_err_ptr(err); } +COMPAT_VERSION(btf_dump__new_deprecated, btf_dump__new, LIBBPF_0.0.4) +struct btf_dump *btf_dump__new_deprecated(const struct btf *btf, + const struct btf_ext *btf_ext, + const struct btf_dump_opts *opts, + btf_dump_printf_fn_t printf_fn) +{ + if (!printf_fn) + return libbpf_err_ptr(-EINVAL); + return btf_dump__new_v0_6_0(btf, printf_fn, opts ? opts->ctx : NULL, opts); +} + static int btf_dump_resize(struct btf_dump *d) { int err, last_id = btf__type_cnt(d->btf) - 1; diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map index b8c8d14621d2..07762d6723ef 100644 --- a/tools/lib/bpf/libbpf.map +++ b/tools/lib/bpf/libbpf.map @@ -407,4 +407,6 @@ LIBBPF_0.6.0 { btf__dedup_deprecated; btf__raw_data; btf__type_cnt; + btf_dump__new; + btf_dump__new_deprecated; } LIBBPF_0.5.0; |