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MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: bpf-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Fri, 18 Oct 2019 12:34:04 +0200, Jiri Olsa wrote: > The bpftool interface stays the same, but now it's possible > to run it over BTF raw data, like: > > $ bpftool btf dump file /sys/kernel/btf/vmlinux > libbpf: failed to get EHDR from /sys/kernel/btf/vmlinux > [1] INT '(anon)' size=4 bits_offset=0 nr_bits=32 encoding=(none) > [2] INT 'long unsigned int' size=8 bits_offset=0 nr_bits=64 encoding=(none) > [3] CONST '(anon)' type_id=2 > > I'm also adding err init to 0 because I was getting uninitialized > warnings from gcc. > > Signed-off-by: Jiri Olsa > --- > tools/bpf/bpftool/btf.c | 47 ++++++++++++++++++++++++++++++++++++----- > 1 file changed, 42 insertions(+), 5 deletions(-) > > diff --git a/tools/bpf/bpftool/btf.c b/tools/bpf/bpftool/btf.c > index 9a9376d1d3df..100fb7e02329 100644 > --- a/tools/bpf/bpftool/btf.c > +++ b/tools/bpf/bpftool/btf.c > @@ -12,6 +12,9 @@ > #include > #include > #include > +#include > +#include > +#include > > #include "btf.h" > #include "json_writer.h" > @@ -388,6 +391,35 @@ static int dump_btf_c(const struct btf *btf, > return err; > } > > +static struct btf *btf__parse_raw(const char *file) > +{ > + struct btf *btf = ERR_PTR(-EINVAL); > + __u8 *buf = NULL; Please drop the inits > + struct stat st; > + FILE *f; > + > + if (stat(file, &st)) > + return btf; And return constants here > + f = fopen(file, "rb"); > + if (!f) > + return btf; and here > + buf = malloc(st.st_size); > + if (!buf) > + goto err; and jump to the right place here. > + if ((size_t) st.st_size != fread(buf, 1, st.st_size, f)) > + goto err; > + > + btf = btf__new(buf, st.st_size); > + > +err: The prefix for error labels which is shared with non-error path is exit_ > + free(buf); > + fclose(f); > + return btf; > +} > + > static int do_dump(int argc, char **argv) > { > struct btf *btf = NULL; > @@ -397,7 +429,7 @@ static int do_dump(int argc, char **argv) > __u32 btf_id = -1; > const char *src; > int fd = -1; > - int err; > + int err = 0; This change looks unnecessary. > if (!REQ_ARGS(2)) { > usage(); > @@ -468,10 +500,15 @@ static int do_dump(int argc, char **argv) > btf = btf__parse_elf(*argv, NULL); > if (IS_ERR(btf)) { > err = PTR_ERR(btf); > - btf = NULL; > - p_err("failed to load BTF from %s: %s", > - *argv, strerror(err)); > - goto done; > + if (err == -LIBBPF_ERRNO__FORMAT) > + btf = btf__parse_raw(*argv); > + if (IS_ERR(btf)) { > + btf = NULL; > + /* Display the original error value. */ > + p_err("failed to load BTF from %s: %s", > + *argv, strerror(err)); > + goto done; > + } > } > NEXT_ARG(); > } else {