/* * nice() for uClibc * * Copyright (C) 2005 by Manuel Novoa III <mjn3@codepoet.org> * Copyright (C) 2000-2006 Erik Andersen <andersen@uclibc.org> * * Licensed under the LGPL v2.1, see the file COPYING.LIB in this tarball. */ #include <sys/syscall.h> #include <unistd.h> #include <sys/resource.h> #ifdef __NR_nice # define __NR___syscall_nice __NR_nice static __inline__ _syscall1(int, __syscall_nice, int, incr) #else # include <limits.h> static __inline__ int int_add_no_wrap(int a, int b) { if (b < 0) { if (a < INT_MIN - b) return INT_MIN; } else { if (a > INT_MAX - b) return INT_MAX; } return a + b; } static __inline__ int __syscall_nice(int incr) { int old_priority; # if 1 /* This should never fail. */ old_priority = getpriority(PRIO_PROCESS, 0); # else /* But if you want to be paranoid... */ int old_errno; old_errno = errno; __set_errno(0); old_priority = getpriority(PRIO_PROCESS, 0); if ((old_priority == -1) && errno) { return -1; } __set_errno(old_errno); # endif if (setpriority(PRIO_PROCESS, 0, int_add_no_wrap(old_priority, incr))) { __set_errno(EPERM); /* SUSv3 mandates EPERM for nice failure. */ return -1; } return 0; } #endif int nice(int incr) { if (__syscall_nice(incr)) { return -1; } return getpriority(PRIO_PROCESS, 0); }