[PATCH 4.14 109/109] perf tools: Fix snprint warnings for gcc 8

Greg Kroah-Hartman
2018-10-16T17:22:19Z

From: Jiri Olsa <jolsa@kernel.org>

commit 77f18153c080855e1c3fb520ca31a4e61530121d upstream.

With gcc 8 we get new set of snprintf() warnings that breaks the
compilation, one example:

tests/mem.c: In function ‘check’:
tests/mem.c:19:48: error: ‘%s’ directive output may be truncated writing \
up to 99 bytes into a region of size 89 [-Werror=format-truncation=]
snprintf(failure, sizeof failure, "unexpected %s", out);

The gcc docs says:

To avoid the warning either use a bigger buffer or handle the
function's return value which indicates whether or not its output
has been truncated.

Given that all these warnings are harmless, because the code either
properly fails due to uncomplete file path or we don't care for
truncated output at all, I'm changing all those snprintf() calls to
scnprintf(), which actually 'checks' for the snprint return value so the
gcc stays silent.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Link: http://lkml.kernel.org/r/20180319082902.4518-1-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Ignat Korchagin <ignat@cloudflare.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
tools/perf/builtin-script.c | 22 +++++++++++-----------
tools/perf/tests/attr.c | 4 ++--
tools/perf/tests/mem.c | 2 +-
tools/perf/tests/pmu.c | 2 +-
tools/perf/util/cgroup.c | 2 +-
tools/perf/util/parse-events.c | 4 ++--
tools/perf/util/pmu.c | 2 +-
7 files changed, 19 insertions(+), 19 deletions(-)

--- a/tools/perf/builtin-script.c
+++ b/tools/perf/builtin-script.c
@@ -2304,8 +2304,8 @@ static int list_available_scripts(const
}

for_each_lang(scripts_path, scripts_dir, lang_dirent) {
- snprintf(lang_path, MAXPATHLEN, "%s/%s/bin", scripts_path,
- lang_dirent->d_name);
+ scnprintf(lang_path, MAXPATHLEN, "%s/%s/bin", scripts_path,
+ lang_dirent->d_name);
lang_dir = opendir(lang_path);
if (!lang_dir)
continue;
@@ -2314,8 +2314,8 @@ static int list_available_scripts(const
script_root = get_script_root(script_dirent, REPORT_SUFFIX);
if (script_root) {
desc = script_desc__findnew(script_root);
- snprintf(script_path, MAXPATHLEN, "%s/%s",
- lang_path, script_dirent->d_name);
+ scnprintf(script_path, MAXPATHLEN, "%s/%s",
+ lang_path, script_dirent->d_name);
read_script_info(desc, script_path);
free(script_root);
}
@@ -2351,7 +2351,7 @@ static int check_ev_match(char *dir_name
int match, len;
FILE *fp;

- sprintf(filename, "%s/bin/%s-record", dir_name, scriptname);
+ scnprintf(filename, MAXPATHLEN, "%s/bin/%s-record", dir_name, scriptname);

fp = fopen(filename, "r");
if (!fp)
@@ -2427,8 +2427,8 @@ int find_scripts(char **scripts_array, c
}

for_each_lang(scripts_path, scripts_dir, lang_dirent) {
- snprintf(lang_path, MAXPATHLEN, "%s/%s", scripts_path,
- lang_dirent->d_name);
+ scnprintf(lang_path, MAXPATHLEN, "%s/%s", scripts_path,
+ lang_dirent->d_name);
#ifdef NO_LIBPERL
if (strstr(lang_path, "perl"))
continue;
@@ -2483,8 +2483,8 @@ static char *get_script_path(const char
return NULL;

for_each_lang(scripts_path, scripts_dir, lang_dirent) {
- snprintf(lang_path, MAXPATHLEN, "%s/%s/bin", scripts_path,
- lang_dirent->d_name);
+ scnprintf(lang_path, MAXPATHLEN, "%s/%s/bin", scripts_path,
+ lang_dirent->d_name);
lang_dir = opendir(lang_path);
if (!lang_dir)
continue;
@@ -2495,8 +2495,8 @@ static char *get_script_path(const char
free(__script_root);
closedir(lang_dir);
closedir(scripts_dir);
- snprintf(script_path, MAXPATHLEN, "%s/%s",
- lang_path, script_dirent->d_name);
+ scnprintf(script_path, MAXPATHLEN, "%s/%s",
+ lang_path, script_dirent->d_name);
return strdup(script_path);
}
free(__script_root);
--- a/tools/perf/tests/attr.c
+++ b/tools/perf/tests/attr.c
@@ -164,8 +164,8 @@ static int run_dir(const char *d, const
if (verbose > 0)
vcnt++;

- snprintf(cmd, 3*PATH_MAX, PYTHON " %s/attr.py -d %s/attr/ -p %s %.*s",
- d, d, perf, vcnt, v);
+ scnprintf(cmd, 3*PATH_MAX, PYTHON " %s/attr.py -d %s/attr/ -p %s %.*s",
+ d, d, perf, vcnt, v);

return system(cmd) ? TEST_FAIL : TEST_OK;
}
--- a/tools/perf/tests/mem.c
+++ b/tools/perf/tests/mem.c
@@ -16,7 +16,7 @@ static int check(union perf_mem_data_src

n = perf_mem__snp_scnprintf(out, sizeof out, &mi);
n += perf_mem__lvl_scnprintf(out + n, sizeof out - n, &mi);
- snprintf(failure, sizeof failure, "unexpected %s", out);
+ scnprintf(failure, sizeof failure, "unexpected %s", out);
TEST_ASSERT_VAL(failure, !strcmp(string, out));
return 0;
}
--- a/tools/perf/tests/pmu.c
+++ b/tools/perf/tests/pmu.c
@@ -98,7 +98,7 @@ static char *test_format_dir_get(void)
struct test_format *format = &test_formats[i];
FILE *file;

- snprintf(name, PATH_MAX, "%s/%s", dir, format->name);
+ scnprintf(name, PATH_MAX, "%s/%s", dir, format->name);

file = fopen(name, "w");
if (!file)
--- a/tools/perf/util/cgroup.c
+++ b/tools/perf/util/cgroup.c
@@ -78,7 +78,7 @@ static int open_cgroup(char *name)
if (cgroupfs_find_mountpoint(mnt, PATH_MAX + 1))
return -1;

- snprintf(path, PATH_MAX, "%s/%s", mnt, name);
+ scnprintf(path, PATH_MAX, "%s/%s", mnt, name);

fd = open(path, O_RDONLY);
if (fd == -1)
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -202,8 +202,8 @@ struct tracepoint_path *tracepoint_id_to

for_each_event(sys_dirent, evt_dir, evt_dirent) {

- snprintf(evt_path, MAXPATHLEN, "%s/%s/id", dir_path,
- evt_dirent->d_name);
+ scnprintf(evt_path, MAXPATHLEN, "%s/%s/id", dir_path,
+ evt_dirent->d_name);
fd = open(evt_path, O_RDONLY);
if (fd < 0)
continue;
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -349,7 +349,7 @@ static int pmu_aliases_parse(char *dir,
if (pmu_alias_info_file(name))
continue;

- snprintf(path, PATH_MAX, "%s/%s", dir, name);
+ scnprintf(path, PATH_MAX, "%s/%s", dir, name);

file = fopen(path, "r");
if (!file) {