hust testsuite: fix a false positive

[oweals/busybox.git] / miscutils / taskset.c

diff --git a/miscutils/taskset.c b/miscutils/taskset.c
index 100b1d926fe3df61e564baf0220334412fb36729..fb352ab8dc5d64d8e314ea8d058182d5a59386b3 100644 (file)
--- a/miscutils/taskset.c
+++ b/miscutils/taskset.c
@@ -75,27 +75,26 @@ static char *from_cpuset(cpu_set_t *mask)
 #define TASKSET_PRINTF_MASK "%llx"
 static unsigned long long from_cpuset(cpu_set_t *mask)
 {
-       char *p = (void*)mask;
+       BUILD_BUG_ON(CPU_SETSIZE < 8*sizeof(int));
 
-       BUILD_BUG_ON(CPU_SETSIZE < sizeof(int));
-
-       /* Take the least significant bits. Careful!
-        * Consider both CPU_SETSIZE=4 and CPU_SETSIZE=1024 cases
+       /* Take the least significant bits. Assume cpu_set_t is
+        * implemented as an array of unsigned long or unsigned
+        * int.
         */
-#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;
+       if (CPU_SETSIZE < 8*sizeof(long))
+               return *(unsigned*)mask;
+       if (CPU_SETSIZE < 8*sizeof(long long))
+               return *(unsigned long*)mask;
+# if BB_BIG_ENDIAN
+       if (sizeof(long long) > sizeof(long)) {
+               /* We can put two long in the long long, but they have to
+                * be swapped: the least significant word comes first in the
+                * array */
+               unsigned long *p = (void*)mask;
+               return p[0] + ((unsigned long long)p[1] << (8*sizeof(long)));
+       }
+# endif
+       return *(unsigned long long*)mask;
 }
 #endif