source: branches/3.2/mindi-busybox/miscutils/ionice.c @ 3232

Last change on this file since 3232 was 3232, checked in by Bruno Cornec, 7 years ago
  • Update mindi-busybox to 1.21.1
  • Property svn:eol-style set to native
File size: 2.4 KB
Line 
1/* vi: set sw=4 ts=4: */
2/*
3 * ionice implementation for busybox based on linux-utils-ng 2.14
4 *
5 * Copyright (C) 2008 by  <u173034@informatik.uni-oldenburg.de>
6 *
7 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
8 */
9
10//usage:#define ionice_trivial_usage
11//usage:    "[-c 1-3] [-n 0-7] [-p PID] [PROG]"
12//usage:#define ionice_full_usage "\n\n"
13//usage:       "Change I/O priority and class\n"
14//usage:     "\n    -c  Class. 1:realtime 2:best-effort 3:idle"
15//usage:     "\n    -n  Priority"
16
17#include <sys/syscall.h>
18#include <asm/unistd.h>
19#include "libbb.h"
20
21static int ioprio_set(int which, int who, int ioprio)
22{
23    return syscall(SYS_ioprio_set, which, who, ioprio);
24}
25
26static int ioprio_get(int which, int who)
27{
28    return syscall(SYS_ioprio_get, which, who);
29}
30
31enum {
32    IOPRIO_WHO_PROCESS = 1,
33    IOPRIO_WHO_PGRP,
34    IOPRIO_WHO_USER
35};
36
37enum {
38    IOPRIO_CLASS_NONE,
39    IOPRIO_CLASS_RT,
40    IOPRIO_CLASS_BE,
41    IOPRIO_CLASS_IDLE
42};
43
44static const char to_prio[] = "none\0realtime\0best-effort\0idle";
45
46#define IOPRIO_CLASS_SHIFT      13
47
48int ionice_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
49int ionice_main(int argc UNUSED_PARAM, char **argv)
50{
51    /* Defaults */
52    int ioclass = 0;
53    int pri = 0;
54    int pid = 0; /* affect own porcess */
55    int opt;
56    enum {
57        OPT_n = 1,
58        OPT_c = 2,
59        OPT_p = 4,
60    };
61
62    /* Numeric params */
63    opt_complementary = "n+:c+:p+";
64    /* '+': stop at first non-option */
65    opt = getopt32(argv, "+n:c:p:", &pri, &ioclass, &pid);
66    argv += optind;
67
68    if (opt & OPT_c) {
69        if (ioclass > 3)
70            bb_error_msg_and_die("bad class %d", ioclass);
71// Do we need this (compat?)?
72//      if (ioclass == IOPRIO_CLASS_NONE)
73//          ioclass = IOPRIO_CLASS_BE;
74//      if (ioclass == IOPRIO_CLASS_IDLE) {
75//          //if (opt & OPT_n)
76//          //  bb_error_msg("ignoring priority for idle class");
77//          pri = 7;
78//      }
79    }
80
81    if (!(opt & (OPT_n|OPT_c))) {
82        if (!(opt & OPT_p) && *argv)
83            pid = xatoi_positive(*argv);
84
85        pri = ioprio_get(IOPRIO_WHO_PROCESS, pid);
86        if (pri == -1)
87            bb_perror_msg_and_die("ioprio_%cet", 'g');
88
89        ioclass = (pri >> IOPRIO_CLASS_SHIFT) & 0x3;
90        pri &= 0xff;
91        printf((ioclass == IOPRIO_CLASS_IDLE) ? "%s\n" : "%s: prio %d\n",
92                nth_string(to_prio, ioclass), pri);
93    } else {
94//printf("pri=%d class=%d val=%x\n",
95//pri, ioclass, pri | (ioclass << IOPRIO_CLASS_SHIFT));
96        pri |= (ioclass << IOPRIO_CLASS_SHIFT);
97        if (ioprio_set(IOPRIO_WHO_PROCESS, pid, pri) == -1)
98            bb_perror_msg_and_die("ioprio_%cet", 's');
99        if (argv[0]) {
100            BB_EXECVP_or_die(argv);
101        }
102    }
103
104    return EXIT_SUCCESS;
105}
Note: See TracBrowser for help on using the repository browser.