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