1 files changed, 49 insertions, 39 deletions

diff --git a/miscutils/taskset.c b/miscutils/taskset.c
index e64fd655b..6247aa869 100644
--- a/miscutils/taskset.c
+++ b/miscutils/taskset.c
@@ -39,61 +39,71 @@ static char *__from_cpuset(cpu_set_t *mask)
 #define from_cpuset(mask) (*(unsigned*)(void*)&(mask))
 #endif
 
-#define OPT_p 1
 
 int taskset_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
-int taskset_main(int argc, char **argv)
+int taskset_main(int argc ATTRIBUTE_UNUSED, char **argv)
 {
-        cpu_set_t mask, new_mask;
+        cpu_set_t mask;
         pid_t pid = 0;
-        unsigned opt;
-        const char *state = "current\0new";
-        char *p_opt = NULL, *aff = NULL;
+        unsigned opt_p;
+        const char *current_new;
+        char *pid_str;
+        char *aff = aff; /* for compiler */
 
-        opt = getopt32(argv, "+p:", &p_opt);
+        opt_complementary = "-1"; /* at least 1 arg */
+        opt_p = getopt32(argv, "+p");
+        argv += optind;
 
-        if (opt & OPT_p) {
-                if (argc == optind+1) { /* -p <aff> <pid> */
-                        aff = p_opt;
-                        p_opt = argv[optind];
-                }
-                argv += optind; /* me -p <arg> */
-                pid = xatoul_range(p_opt, 1, ULONG_MAX); /* -p <pid> */
-        } else
-                aff = *++argv; /* <aff> <cmd...> */
-        if (aff) {
-                unsigned i = 0;
-                unsigned long l = xstrtol_range(aff, 0, 1, LONG_MAX);
-
-                CPU_ZERO(&new_mask);
-                while (i < CPU_SETSIZE && l >= (1<<i)) {
-                        if ((1<<i) & l)
-                                CPU_SET(i, &new_mask);
-                        ++i;
+        if (opt_p) {
+                pid_str = *argv++;
+                if (*argv) { /* "-p <aff> <pid> ...rest.is.ignored..." */
+                        aff = pid_str;
+                        pid_str = *argv; /* NB: *argv != NULL in this case */
                 }
+                /* else it was just "-p <pid>", and *argv == NULL */
+                pid = xatoul_range(pid_str, 1, ((unsigned)(pid_t)ULONG_MAX) >> 1);
+        } else {
+                aff = *argv++; /* <aff> <cmd...> */
+                if (!*argv)
+                        bb_show_usage();
         }
 
-        if (opt & OPT_p) {
+        current_new = "current\0new";
+        if (opt_p) {
  print_aff:
                 if (sched_getaffinity(pid, sizeof(mask), &mask) < 0)
-                        bb_perror_msg_and_die("failed to %cet pid %d's affinity", 'g', pid);
+                        bb_perror_msg_and_die("can't %cet pid %d's affinity", 'g', pid);
                 printf("pid %d's %s affinity mask: "TASKSET_PRINTF_MASK"\n",
-                                pid, state, from_cpuset(mask));
-                if (!*argv) /* no new affinity given or we did print already, done. */
+                                pid, current_new, from_cpuset(mask));
+                if (!*argv) {
+                        /* Either it was just "-p <pid>",
+                         * or it was "-p <aff> <pid>" and we came here
+                         * for the second time (see goto below) */
                         return EXIT_SUCCESS;
+                }
+                *argv = NULL;
+                current_new += 8; /* "new" */
         }
 
-        if (sched_setaffinity(pid, sizeof(new_mask), &new_mask))
-                bb_perror_msg_and_die("failed to %cet pid %d's affinity", 's', pid);
-        if (opt & OPT_p) {
-                state += 8;
-                ++argv;
-                goto print_aff;
+        { /* Affinity was specified, translate it into cpu_set_t */
+                unsigned i;
+                /* Do not allow zero mask: */
+                unsigned long long m = xstrtoull_range(aff, 0, 1, ULLONG_MAX);
+                CPU_ZERO(&mask);
+                for (i = 0; i < CPU_SETSIZE; i++) {
+                        unsigned long long bit = (1ULL << i);
+                        if (bit & m)
+                                CPU_SET(i, &mask);
+                }
         }
-        ++argv;
+
+        /* Set pid's or our own (pid==0) affinity */
+        if (sched_setaffinity(pid, sizeof(mask), &mask))
+                bb_perror_msg_and_die("can't %cet pid %d's affinity", 's', pid);
+
+        if (!*argv) /* "-p <aff> <pid> [...ignored...]" */
+                goto print_aff; /* print new affinity and exit */
+
         BB_EXECVP(*argv, argv);
         bb_simple_perror_msg_and_die(*argv);
 }
-#undef OPT_p
-#undef TASKSET_PRINTF_MASK
-#undef from_cpuset