133 lines
2.7 KiB
C
133 lines
2.7 KiB
C
/* vi: set sw=4 ts=4: */
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/* dmesg.c -- Print out the contents of the kernel ring buffer
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* Created: Sat Oct 9 16:19:47 1993
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* Revised: Thu Oct 28 21:52:17 1993 by faith@cs.unc.edu
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* Copyright 1993 Theodore Ts'o (tytso@athena.mit.edu)
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* This program comes with ABSOLUTELY NO WARRANTY.
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* Modifications by Rick Sladkey (jrs@world.std.com)
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* Larger buffersize 3 June 1998 by Nicolai Langfeldt, based on a patch
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* by Peeter Joot. This was also suggested by John Hudson.
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* 1999-02-22 Arkadiusz Mi¶kiewicz <misiek@misiek.eu.org>
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* - added Native Language Support
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*
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* from util-linux -- adapted for busybox by
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* Erik Andersen <andersee@debian.org>. I ripped out Native Language
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* Support, replaced getopt, added some gotos for redundant stuff.
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*/
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#include "internal.h"
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#include <linux/unistd.h>
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#include <stdio.h>
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#include <stdlib.h>
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#if __GNU_LIBRARY__ < 5
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#ifndef __alpha__
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# define __NR_klogctl __NR_syslog
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static inline _syscall3(int, klogctl, int, type, char *, b, int, len);
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#else /* __alpha__ */
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#define klogctl syslog
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#endif
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#else
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# include <sys/klog.h>
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#endif
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static const char dmesg_usage[] = "dmesg [-c] [-n LEVEL] [-s SIZE]\n"
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#ifndef BB_FEATURE_TRIVIAL_HELP
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"\nPrints or controls the kernel ring buffer\n\n"
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"Options:\n"
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"\t-c\t\tClears the ring buffer's contents after printing\n"
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"\t-n LEVEL\tSets console logging level\n"
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"\t-s SIZE\t\tUse a buffer of size SIZE\n"
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#endif
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;
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int dmesg_main(int argc, char **argv)
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{
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char *buf;
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int bufsize = 8196;
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int i;
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int n;
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int level = 0;
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int lastc;
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int cmd = 3;
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int stopDoingThat;
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argc--;
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argv++;
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/* Parse any options */
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while (argc && **argv == '-') {
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stopDoingThat = FALSE;
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while (stopDoingThat == FALSE && *++(*argv)) {
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switch (**argv) {
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case 'c':
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cmd = 4;
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break;
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case 'n':
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cmd = 8;
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if (--argc == 0)
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goto end;
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level = atoi(*(++argv));
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if (--argc > 0)
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++argv;
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stopDoingThat = TRUE;
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break;
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case 's':
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if (--argc == 0)
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goto end;
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bufsize = atoi(*(++argv));
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if (--argc > 0)
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++argv;
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stopDoingThat = TRUE;
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break;
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default:
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goto end;
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}
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}
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}
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if (argc > 1) {
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goto end;
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}
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if (cmd == 8) {
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n = klogctl(cmd, NULL, level);
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if (n < 0) {
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goto klogctl_error;
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}
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exit(TRUE);
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}
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if (bufsize < 4096)
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bufsize = 4096;
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buf = (char *) xmalloc(bufsize);
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n = klogctl(cmd, buf, bufsize);
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if (n < 0) {
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goto klogctl_error;
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}
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lastc = '\n';
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for (i = 0; i < n; i++) {
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if ((i == 0 || buf[i - 1] == '\n') && buf[i] == '<') {
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i++;
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while (buf[i] >= '0' && buf[i] <= '9')
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i++;
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if (buf[i] == '>')
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i++;
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}
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lastc = buf[i];
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putchar(lastc);
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}
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if (lastc != '\n')
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putchar('\n');
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exit(TRUE);
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end:
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usage(dmesg_usage);
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exit(FALSE);
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klogctl_error:
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perror("klogctl");
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return(FALSE);
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}
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