tools, bpftool: Fix warning on ignored return value for 'read'

When building bpftool, a warning was introduced by commit a943646036
("bpftool: Allow to read btf as raw data"), because the return value
from a call to 'read()' is ignored. Let's address it.

Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20191119111706.22440-1-quentin.monnet@netronome.com
This commit is contained in:
Quentin Monnet 2019-11-19 11:17:06 +00:00 committed by Alexei Starovoitov
parent 5d946c5abb
commit a0f17cc666

View File

@ -428,15 +428,15 @@ exit_close:
static bool is_btf_raw(const char *file)
{
__u16 magic = 0;
int fd;
int fd, nb_read;
fd = open(file, O_RDONLY);
if (fd < 0)
return false;
read(fd, &magic, sizeof(magic));
nb_read = read(fd, &magic, sizeof(magic));
close(fd);
return magic == BTF_MAGIC;
return nb_read == sizeof(magic) && magic == BTF_MAGIC;
}
static int do_dump(int argc, char **argv)