diff options
Diffstat (limited to 'miscutils/taskset.c')
| -rw-r--r-- | miscutils/taskset.c | 48 |
1 files changed, 35 insertions, 13 deletions
diff --git a/miscutils/taskset.c b/miscutils/taskset.c index 3175af1..b43d42e 100644 --- a/miscutils/taskset.c +++ b/miscutils/taskset.c @@ -11,31 +11,53 @@ #if ENABLE_FEATURE_TASKSET_FANCY #define TASKSET_PRINTF_MASK "%s" -#define from_cpuset(x) __from_cpuset(&x) /* craft a string from the mask */ -static char *__from_cpuset(cpu_set_t *mask) +static char *from_cpuset(cpu_set_t *mask) { int i; - char *ret = 0, *str = xzalloc(9); + char *ret = NULL; + char *str = xzalloc((CPU_SETSIZE / 4) + 1); /* we will leak it */ for (i = CPU_SETSIZE - 4; i >= 0; i -= 4) { - char val = 0; + int val = 0; int off; for (off = 0; off <= 3; ++off) - if (CPU_ISSET(i+off, mask)) - val |= 1<<off; - + if (CPU_ISSET(i + off, mask)) + val |= 1 << off; if (!ret && val) ret = str; - *str++ = (val-'0'<=9) ? (val+48) : (val+87); + *str++ = bb_hexdigits_upcase[val] | 0x20; } return ret; } #else -#define TASKSET_PRINTF_MASK "%x" -/* (void*) cast is for battling gcc: */ -/* "dereferencing type-punned pointer will break strict-aliasing rules" */ -#define from_cpuset(mask) (*(unsigned*)(void*)&(mask)) +#define TASKSET_PRINTF_MASK "%llx" +static unsigned long long from_cpuset(cpu_set_t *mask) +{ + struct BUG_CPU_SETSIZE_is_too_small { + char BUG_CPU_SETSIZE_is_too_small[ + CPU_SETSIZE < sizeof(int) ? -1 : 1]; + }; + char *p = (void*)mask; + + /* Take the least significant bits. Careful! + * Consider both CPU_SETSIZE=4 and CPU_SETSIZE=1024 cases + */ +#if BB_BIG_ENDIAN + /* For big endian, it means LAST bits */ + if (CPU_SETSIZE < sizeof(long)) + p += CPU_SETSIZE - sizeof(int); + else if (CPU_SETSIZE < sizeof(long long)) + p += CPU_SETSIZE - sizeof(long); + else + p += CPU_SETSIZE - sizeof(long long); +#endif + if (CPU_SETSIZE < sizeof(long)) + return *(unsigned*)p; + if (CPU_SETSIZE < sizeof(long long)) + return *(unsigned long*)p; + return *(unsigned long long*)p; +} #endif @@ -78,7 +100,7 @@ int taskset_main(int argc UNUSED_PARAM, char **argv) if (sched_getaffinity(pid, sizeof(mask), &mask) < 0) 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, current_new, from_cpuset(mask)); + pid, current_new, from_cpuset(&mask)); if (!*argv) { /* Either it was just "-p <pid>", * or it was "-p <aff> <pid>" and we came here |