diff options
| -rw-r--r-- | src/unistd/nice.c | 14 |
1 files changed, 9 insertions, 5 deletions
diff --git a/src/unistd/nice.c b/src/unistd/nice.c index da569967..6c25c8c3 100644 --- a/src/unistd/nice.c +++ b/src/unistd/nice.c @@ -1,12 +1,16 @@ #include <unistd.h> #include <sys/resource.h> +#include <limits.h> #include "syscall.h" int nice(int inc) { -#ifdef SYS_nice - return syscall(SYS_nice, inc); -#else - return setpriority(PRIO_PROCESS, 0, getpriority(PRIO_PROCESS, 0)+inc); -#endif + int prio = inc; + // Only query old priority if it can affect the result. + // This also avoids issues with integer overflow. + if (inc > -2*NZERO && inc < 2*NZERO) + prio += getpriority(PRIO_PROCESS, 0); + if (prio > NZERO-1) prio = NZERO-1; + if (prio < -NZERO) prio = -NZERO; + return setpriority(PRIO_PROCESS, 0, prio) ? -1 : prio; } |