taskset: use iterate_on_dir()

function                                             old     new   delta
iter                                                   -      27     +27
process_pid_str                                      854     856      +2
taskset_main                                         181     135     -46
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 1/1 up/down: 29/-46)            Total: -17 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

1 files changed, 17 insertions, 18 deletions

diff --git a/util-linux/taskset.c b/util-linux/taskset.c
index 47e989792..afe2f04d2 100644
--- a/util-linux/taskset.c
+++ b/util-linux/taskset.c
@@ -213,7 +213,7 @@ enum {
         OPT_c = (1 << 2) * ENABLE_FEATURE_TASKSET_CPULIST,
 };
 
-static void process_pid_str(const char *pid_str, unsigned opts, char *aff)
+static int process_pid_str(const char *pid_str, unsigned opts, char *aff)
 {
         ul *mask;
         unsigned mask_size_in_bytes;
@@ -237,7 +237,7 @@ static void process_pid_str(const char *pid_str, unsigned opts, char *aff)
                         /* Either it was just "-p <pid>",
                          * or it was "-p <aff> <pid>" and we came here
                          * for the second time (see goto below) */
-                        return;
+                        return 0;
                 }
                 current_new = "new";
         }
@@ -312,6 +312,14 @@ static void process_pid_str(const char *pid_str, unsigned opts, char *aff)
                 aff = NULL;
                 goto print_aff; /* print new affinity and exit */
         }
+        return 0;
+}
+
+static int FAST_FUNC iter(const char *dn UNUSED_PARAM, struct dirent *ent, void *aff)
+{
+        if (isdigit(ent->d_name[0]))
+                return process_pid_str(ent->d_name, option_mask32, aff);
+        return 0;
 }
 
 int taskset_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
@@ -341,29 +349,20 @@ int taskset_main(int argc UNUSED_PARAM, char **argv)
 
         pid_str = aff;
         if (*argv) /* "-p <aff> <pid> ...rest.is.ignored..." */
-                pid_str = *argv; /* NB: *argv != NULL in this case */
+                pid_str = *argv;
         else
                 aff = NULL;
 
         if (opts & OPT_a) {
                 char *dn;
-                DIR *dir;
-                struct dirent *ent;
+                int r;
 
                 dn = xasprintf("/proc/%s/task", pid_str);
-                dir = opendir(dn);
+                r = iterate_on_dir(dn, iter, aff);
                 IF_FEATURE_CLEAN_UP(free(dn);)
-                if (!dir) {
-                        goto no_threads;
-                }
-                while ((ent = readdir(dir)) != NULL) {
-                        if (isdigit(ent->d_name[0]))
-                                process_pid_str(ent->d_name, opts, aff);
-                }
-                IF_FEATURE_CLEAN_UP(closedir(dir);)
-        } else {
- no_threads:
-                process_pid_str(pid_str, opts, aff);
+                if (r == 0)
+                        return r; /* EXIT_SUCCESS */
+                /* else: no /proc/PID/task, act as if no -a was given */
         }
-        return EXIT_SUCCESS;
+        return process_pid_str(pid_str, opts, aff);
 }