/* 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.
+ * dmesg - display/control kernel ring buffer.
+ *
+ * Copyright 2006 Rob Landley <rob@landley.net>
+ * Copyright 2006 Bernhard Reutner-Fischer <rep.nop@aon.at>
+ *
+ * Licensed under GPLv2, see file LICENSE in this tarball for details.
*/
-#include "internal.h"
-#include <stdio.h>
-#include <stdlib.h>
-
-#if __GNU_LIBRARY__ < 5
-
-#ifndef __alpha__
-# define __NR_klogctl __NR_syslog
-#include <sys/syscall.h>
-static inline _syscall3(int, klogctl, int, type, char *, b, int, len);
-#else /* __alpha__ */
-#define klogctl syslog
-#endif
+#include <sys/klog.h>
+#include "libbb.h"
-#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)
+int dmesg_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int dmesg_main(int argc UNUSED_PARAM, char **argv)
{
+ int len;
char *buf;
- int bufsize = 8196;
- int i;
- int n;
- int level = 0;
- int lastc;
- int cmd = 3;
- int stopDoingThat;
-
- argc--;
- argv++;
+ char *size, *level;
+ unsigned flags = getopt32(argv, "cs:n:", &size, &level);
+ enum {
+ OPT_c = 1<<0,
+ OPT_s = 1<<1,
+ OPT_n = 1<<2
+ };
- /* 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 (flags & OPT_n) {
+ if (klogctl(8, NULL, xatoul_range(level, 0, 10)))
+ bb_perror_msg_and_die("klogctl");
+ return EXIT_SUCCESS;
}
- if (argc > 1) {
- goto end;
- }
+ len = (flags & OPT_s) ? xatoul_range(size, 2, INT_MAX) : 16384;
+ buf = xmalloc(len);
+ len = klogctl(3 + (flags & OPT_c), buf, len);
+ if (len < 0)
+ bb_perror_msg_and_die("klogctl");
+ if (len == 0)
+ return EXIT_SUCCESS;
- if (cmd == 8) {
- n = klogctl(cmd, NULL, level);
- if (n < 0) {
- goto klogctl_error;
- }
- exit(TRUE);
- }
+ /* Skip <#> at the start of lines, and make sure we end with a newline. */
- if (bufsize < 4096)
- bufsize = 4096;
- buf = (char *) xmalloc(bufsize);
- n = klogctl(cmd, buf, bufsize);
- if (n < 0) {
- goto klogctl_error;
- }
+ if (ENABLE_FEATURE_DMESG_PRETTY) {
+ int last = '\n';
+ int in = 0;
- 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);
+ do {
+ if (last == '\n' && buf[in] == '<')
+ in += 3;
+ else {
+ last = buf[in++];
+ bb_putchar(last);
+ }
+ } while (in < len);
+ if (last != '\n')
+ bb_putchar('\n');
+ } else {
+ full_write(STDOUT_FILENO, buf, len);
+ if (buf[len-1] != '\n')
+ bb_putchar('\n');
}
- if (lastc != '\n')
- putchar('\n');
- exit(TRUE);
- end:
- usage(dmesg_usage);
- exit(FALSE);
- klogctl_error:
- perror("klogctl");
- return(FALSE);
+
+ if (ENABLE_FEATURE_CLEAN_UP) free(buf);
+
+ return EXIT_SUCCESS;
}
projects / oweals / busybox.git / blobdiff