nproc: prepare for arbitrarily large CPU masks

function                                             old     new   delta
get_malloc_cpu_affinity                                -      76     +76
nproc_main                                           216     206     -10
process_pid_str                                      250     206     -44
------------------------------------------------------------------------------
(add/remove: 2/0 grow/shrink: 0/2 up/down: 76/-54)             Total: 22 bytes

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

1 files changed, 5 insertions, 4 deletions

diff --git a/coreutils/nproc.c b/coreutils/nproc.c
index f1d11fa5a..a0d818c59 100644
--- a/coreutils/nproc.c
+++ b/coreutils/nproc.c
@@ -23,13 +23,11 @@
 //usage:     "\n        --ignore=N      Exclude N CPUs"
 //usage:        )
 
-#include <sched.h>
 #include "libbb.h"
 
 int nproc_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int nproc_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
 {
-        unsigned long mask[1024];
         int count = 0;
 #if ENABLE_LONG_OPTS
         int ignore = 0;
@@ -52,9 +50,12 @@ int nproc_main(int argc UNUSED_PARAM, char **argv UNUSED_PARAM)
                 }
         } else
 #endif
-        if (sched_getaffinity(0, sizeof(mask), (void*)mask) == 0) {
+        {
                 int i;
-                for (i = 0; i < ARRAY_SIZE(mask); i++) {
+                unsigned sz = 2 * 1024;
+                unsigned long *mask = get_malloc_cpu_affinity(0, &sz);
+                sz /= sizeof(long);
+                for (i = 0; i < sz; i++) {
                         unsigned long m = mask[i];
                         while (m) {
                                 if (m & 1)