1/* vi: set sw=4 ts=4: */ 2/* 3 * nice implementation for busybox 4 * 5 * Copyright (C) 2005 Manuel Novoa III <mjn3@codepoet.org> 6 * 7 * Licensed under GPLv2 or later, see file LICENSE in this tarball for details. 8 */ 9 10#include <sys/resource.h> 11#include "libbb.h" 12 13int nice_main(int argc, char **argv); 14int nice_main(int argc, char **argv) 15{ 16 int old_priority, adjustment; 17 18 old_priority = getpriority(PRIO_PROCESS, 0); 19 20 if (!*++argv) { /* No args, so (GNU) output current nice value. */ 21 printf("%d\n", old_priority); 22 fflush_stdout_and_exit(EXIT_SUCCESS); 23 } 24 25 adjustment = 10; /* Set default adjustment. */ 26 27 if (argv[0][0] == '-') { 28 if (argv[0][1] == 'n') { /* -n */ 29 if (argv[0][2]) { /* -nNNNN (w/o space) */ 30 argv[0] += 2; argv--; argc++; 31 } 32 } else { /* -NNN (NNN may be negative) == -n NNN */ 33 argv[0] += 1; argv--; argc++; 34 } 35 if (argc < 4) { /* Missing priority and/or utility! */ 36 bb_show_usage(); 37 } 38 adjustment = xatoi_range(argv[1], INT_MIN/2, INT_MAX/2); 39 argv += 2; 40 } 41 42 { /* Set our priority. */ 43 int prio = old_priority + adjustment; 44 45 if (setpriority(PRIO_PROCESS, 0, prio) < 0) { 46 bb_perror_msg_and_die("setpriority(%d)", prio); 47 } 48 } 49 50 BB_EXECVP(*argv, argv); /* Now exec the desired program. */ 51 52 /* The exec failed... */ 53 xfunc_error_retval = (errno == ENOENT) ? 127 : 126; /* SUSv3 */ 54 bb_perror_msg_and_die("%s", *argv); 55} 56