diff options
author | Ian Rogers <irogers@google.com> | 2023-11-27 14:08:17 -0800 |
---|---|---|
committer | Arnaldo Carvalho de Melo <acme@redhat.com> | 2023-11-30 19:25:19 -0300 |
commit | f8846a1a3c54a53f1c30836a2b7143cfa5da223d (patch) | |
tree | bcc40a601f48c13e5ab8ea0de35a2c386ce99334 | |
parent | b6a15269cee255dc5fe75c249c701e3956d892cb (diff) | |
download | linux-stable-f8846a1a3c54a53f1c30836a2b7143cfa5da223d.tar.gz linux-stable-f8846a1a3c54a53f1c30836a2b7143cfa5da223d.tar.bz2 linux-stable-f8846a1a3c54a53f1c30836a2b7143cfa5da223d.zip |
tools api fs: Avoid reading whole file for a 1 byte bool
sysfs__read_bool() used the first byte from a fully read file into a
string. It then looked at the first byte's value. Avoid doing this and
just read the first byte.
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Cc: Changbin Du <changbin.du@huawei.com>
Cc: Colin Ian King <colin.i.king@gmail.com>
Cc: Dmitrii Dolgov <9erthalion6@gmail.com>
Cc: German Gomez <german.gomez@arm.com>
Cc: Guilherme Amadio <amadio@gentoo.org>
Cc: Huacai Chen <chenhuacai@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Clark <james.clark@arm.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: K Prateek Nayak <kprateek.nayak@amd.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Li Dong <lidong@vivo.com>
Cc: Liam Howlett <liam.howlett@oracle.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Ming Wang <wangming01@loongson.cn>
Cc: Nick Terrell <terrelln@fb.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: Sandipan Das <sandipan.das@amd.com>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Steinar H. Gunderson <sesse@google.com>
Cc: Vincent Whitchurch <vincent.whitchurch@axis.com>
Cc: Wenyu Liu <liuwenyu7@huawei.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Link: https://lore.kernel.org/r/20231127220902.1315692-6-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
-rw-r--r-- | tools/lib/api/fs/fs.c | 24 |
1 files changed, 15 insertions, 9 deletions
diff --git a/tools/lib/api/fs/fs.c b/tools/lib/api/fs/fs.c index 004f2af5504b..337fde770e45 100644 --- a/tools/lib/api/fs/fs.c +++ b/tools/lib/api/fs/fs.c @@ -447,15 +447,22 @@ int sysfs__read_str(const char *entry, char **buf, size_t *sizep) int sysfs__read_bool(const char *entry, bool *value) { - char *buf; - size_t size; - int ret; + struct io io; + char bf[16]; + int ret = 0; + char path[PATH_MAX]; + const char *sysfs = sysfs__mountpoint(); + + if (!sysfs) + return -1; - ret = sysfs__read_str(entry, &buf, &size); - if (ret < 0) - return ret; + snprintf(path, sizeof(path), "%s/%s", sysfs, entry); + io.fd = open(path, O_RDONLY); + if (io.fd < 0) + return -errno; - switch (buf[0]) { + io__init(&io, io.fd, bf, sizeof(bf)); + switch (io__get_char(&io)) { case '1': case 'y': case 'Y': @@ -469,8 +476,7 @@ int sysfs__read_bool(const char *entry, bool *value) default: ret = -1; } - - free(buf); + close(io.fd); return ret; } |