perf script: Use readdir() instead of deprecated readdir_r()

The readdir() function is thread safe as long as just one thread uses a
DIR, which is the case in 'perf script', so, to avoid breaking the build
with glibc-2.23.90 (upcoming 2.24), use it instead of readdir_r().

See: http://man7.org/linux/man-pages/man3/readdir.3.html

"However, in modern implementations (including the glibc implementation),
concurrent calls to readdir() that specify different directory streams
are thread-safe.  In cases where multiple threads must read from the
same directory stream, using readdir() with external synchronization is
still preferable to the use of the deprecated readdir_r(3) function."

Noticed while building on a Fedora Rawhide docker container.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-mt3xz7n2hl49ni2vx7kuq74g@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

1 files changed, 34 insertions, 36 deletions

diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
index 59009aa7e2ca..8f6ab2ac855a 100644
--- a/tools/perf/builtin-script.c
+++ b/tools/perf/builtin-script.c
@@ -1415,21 +1415,19 @@ static int is_directory(const char *base_path, const struct dirent *dent)
         return S_ISDIR(st.st_mode);
 }
 
-#define for_each_lang(scripts_path, scripts_dir, lang_dirent, lang_next)\
-        while (!readdir_r(scripts_dir, &lang_dirent, &lang_next) &&     \
-               lang_next)                                               \
-                if ((lang_dirent.d_type == DT_DIR ||                    \
-                     (lang_dirent.d_type == DT_UNKNOWN &&               \
-                      is_directory(scripts_path, &lang_dirent))) &&     \
-                    (strcmp(lang_dirent.d_name, ".")) &&                \
-                    (strcmp(lang_dirent.d_name, "..")))
-
-#define for_each_script(lang_path, lang_dir, script_dirent, script_next)\
-        while (!readdir_r(lang_dir, &script_dirent, &script_next) &&    \
-               script_next)                                             \
-                if (script_dirent.d_type != DT_DIR &&                   \
-                    (script_dirent.d_type != DT_UNKNOWN ||              \
-                     !is_directory(lang_path, &script_dirent)))
+#define for_each_lang(scripts_path, scripts_dir, lang_dirent)           \
+        while ((lang_dirent = readdir(scripts_dir)) != NULL)            \
+                if ((lang_dirent->d_type == DT_DIR ||                   \
+                     (lang_dirent->d_type == DT_UNKNOWN &&              \
+                      is_directory(scripts_path, lang_dirent))) &&      \
+                    (strcmp(lang_dirent->d_name, ".")) &&               \
+                    (strcmp(lang_dirent->d_name, "..")))
+
+#define for_each_script(lang_path, lang_dir, script_dirent)             \
+        while ((script_dirent = readdir(lang_dir)) != NULL)             \
+                if (script_dirent->d_type != DT_DIR &&                  \
+                    (script_dirent->d_type != DT_UNKNOWN ||             \
+                     !is_directory(lang_path, script_dirent)))
 
 
 #define RECORD_SUFFIX                   "-record"
@@ -1575,7 +1573,7 @@ static int list_available_scripts(const struct option *opt __maybe_unused,
                                   const char *s __maybe_unused,
                                   int unset __maybe_unused)
 {
-        struct dirent *script_next, *lang_next, script_dirent, lang_dirent;
+        struct dirent *script_dirent, *lang_dirent;
         char scripts_path[MAXPATHLEN];
         DIR *scripts_dir, *lang_dir;
         char script_path[MAXPATHLEN];
@@ -1590,19 +1588,19 @@ static int list_available_scripts(const struct option *opt __maybe_unused,
         if (!scripts_dir)
                 return -1;
 
-        for_each_lang(scripts_path, scripts_dir, lang_dirent, lang_next) {
+        for_each_lang(scripts_path, scripts_dir, lang_dirent) {
                 snprintf(lang_path, MAXPATHLEN, "%s/%s/bin", scripts_path,
-                         lang_dirent.d_name);
+                         lang_dirent->d_name);
                 lang_dir = opendir(lang_path);
                 if (!lang_dir)
                         continue;
 
-                for_each_script(lang_path, lang_dir, script_dirent, script_next) {
-                        script_root = get_script_root(&script_dirent, REPORT_SUFFIX);
+                for_each_script(lang_path, lang_dir, script_dirent) {
+                        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);
+                                         lang_path, script_dirent->d_name);
                                 read_script_info(desc, script_path);
                                 free(script_root);
                         }
@@ -1690,7 +1688,7 @@ static int check_ev_match(char *dir_name, char *scriptname,
  */
 int find_scripts(char **scripts_array, char **scripts_path_array)
 {
-        struct dirent *script_next, *lang_next, script_dirent, lang_dirent;
+        struct dirent *script_dirent, *lang_dirent;
         char scripts_path[MAXPATHLEN], lang_path[MAXPATHLEN];
         DIR *scripts_dir, *lang_dir;
         struct perf_session *session;
@@ -1713,9 +1711,9 @@ int find_scripts(char **scripts_array, char **scripts_path_array)
                 return -1;
         }
 
-        for_each_lang(scripts_path, scripts_dir, lang_dirent, lang_next) {
+        for_each_lang(scripts_path, scripts_dir, lang_dirent) {
                 snprintf(lang_path, MAXPATHLEN, "%s/%s", scripts_path,
-                         lang_dirent.d_name);
+                         lang_dirent->d_name);
 #ifdef NO_LIBPERL
                 if (strstr(lang_path, "perl"))
                         continue;
@@ -1729,16 +1727,16 @@ int find_scripts(char **scripts_array, char **scripts_path_array)
                 if (!lang_dir)
                         continue;
 
-                for_each_script(lang_path, lang_dir, script_dirent, script_next) {
+                for_each_script(lang_path, lang_dir, script_dirent) {
                         /* Skip those real time scripts: xxxtop.p[yl] */
-                        if (strstr(script_dirent.d_name, "top."))
+                        if (strstr(script_dirent->d_name, "top."))
                                 continue;
                         sprintf(scripts_path_array[i], "%s/%s", lang_path,
-                                script_dirent.d_name);
-                        temp = strchr(script_dirent.d_name, '.');
+                                script_dirent->d_name);
+                        temp = strchr(script_dirent->d_name, '.');
                         snprintf(scripts_array[i],
-                                (temp - script_dirent.d_name) + 1,
-                                "%s", script_dirent.d_name);
+                                (temp - script_dirent->d_name) + 1,
+                                "%s", script_dirent->d_name);
 
                         if (check_ev_match(lang_path,
                                         scripts_array[i], session))
@@ -1756,7 +1754,7 @@ int find_scripts(char **scripts_array, char **scripts_path_array)
 
 static char *get_script_path(const char *script_root, const char *suffix)
 {
-        struct dirent *script_next, *lang_next, script_dirent, lang_dirent;
+        struct dirent *script_dirent, *lang_dirent;
         char scripts_path[MAXPATHLEN];
         char script_path[MAXPATHLEN];
         DIR *scripts_dir, *lang_dir;
@@ -1769,21 +1767,21 @@ static char *get_script_path(const char *script_root, const char *suffix)
         if (!scripts_dir)
                 return NULL;
 
-        for_each_lang(scripts_path, scripts_dir, lang_dirent, lang_next) {
+        for_each_lang(scripts_path, scripts_dir, lang_dirent) {
                 snprintf(lang_path, MAXPATHLEN, "%s/%s/bin", scripts_path,
-                         lang_dirent.d_name);
+                         lang_dirent->d_name);
                 lang_dir = opendir(lang_path);
                 if (!lang_dir)
                         continue;
 
-                for_each_script(lang_path, lang_dir, script_dirent, script_next) {
-                        __script_root = get_script_root(&script_dirent, suffix);
+                for_each_script(lang_path, lang_dir, script_dirent) {
+                        __script_root = get_script_root(script_dirent, suffix);
                         if (__script_root && !strcmp(script_root, __script_root)) {
                                 free(__script_root);
                                 closedir(lang_dir);
                                 closedir(scripts_dir);
                                 snprintf(script_path, MAXPATHLEN, "%s/%s",
-                                         lang_path, script_dirent.d_name);
+                                         lang_path, script_dirent->d_name);
                                 return strdup(script_path);
                         }
                         free(__script_root);