perf tools: Fix snprint warnings for gcc 8

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>
[bwh: Backported to 3.16: Drop changes in tools/perf/tests/mem.c]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

6 files changed, 18 insertions, 18 deletions

diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
index cd1063af1325..d2c8756589fe 100644
--- a/tools/perf/builtin-script.c
+++ b/tools/perf/builtin-script.c
@@ -1235,8 +1235,8 @@ static int list_available_scripts(const struct option *opt __maybe_unused,
 		return -1;
 
 	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;
@@ -1245,8 +1245,8 @@ static int list_available_scripts(const struct option *opt __maybe_unused,
 			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);
 			}
@@ -1282,7 +1282,7 @@ static int check_ev_match(char *dir_name, char *scriptname,
 	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)
@@ -1358,8 +1358,8 @@ int find_scripts(char **scripts_array, char **scripts_path_array)
 	}
 
 	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;
@@ -1414,8 +1414,8 @@ static char *get_script_path(const char *script_root, const char *suffix)
 		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;
@@ -1426,8 +1426,8 @@ static char *get_script_path(const char *script_root, const char *suffix)
 				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);
diff --git a/tools/perf/tests/attr.c b/tools/perf/tests/attr.c
index 2dfc9ad0e6f2..497ab571997b 100644
--- a/tools/perf/tests/attr.c
+++ b/tools/perf/tests/attr.c
@@ -147,8 +147,8 @@ static int run_dir(const char *d, const char *perf)
 	if (verbose)
 		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);
 }
diff --git a/tools/perf/tests/pmu.c b/tools/perf/tests/pmu.c
index 12b322fa3475..567c1e29b7d6 100644
--- a/tools/perf/tests/pmu.c
+++ b/tools/perf/tests/pmu.c
@@ -95,7 +95,7 @@ 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)
diff --git a/tools/perf/util/cgroup.c b/tools/perf/util/cgroup.c
index 88f7be399432..61db98050d1a 100644
--- a/tools/perf/util/cgroup.c
+++ b/tools/perf/util/cgroup.c
@@ -64,7 +64,7 @@ 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)
diff --git a/tools/perf/util/parse-events.c b/tools/perf/util/parse-events.c
index d4eb50acf304..a9d48aa70afc 100644
--- a/tools/perf/util/parse-events.c
+++ b/tools/perf/util/parse-events.c
@@ -182,8 +182,8 @@ struct tracepoint_path *tracepoint_id_to_path(u64 config)
 
 		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;
diff --git a/tools/perf/util/pmu.c b/tools/perf/util/pmu.c
index 17bd6049feaf..f819c23744f5 100644
--- a/tools/perf/util/pmu.c
+++ b/tools/perf/util/pmu.c
@@ -240,7 +240,7 @@ static int pmu_aliases_parse(char *dir, struct list_head *head)
 		if (len > 6 && !strcmp(name + len - 6, ".scale"))
 			continue;
 
-		snprintf(path, PATH_MAX, "%s/%s", dir, name);
+		scnprintf(path, PATH_MAX, "%s/%s", dir, name);
 
 		file = fopen(path, "r");
 		if (!file) {