sys-utils/dmesg.c

   1 /* dmesg.c -- Print out the contents of the kernel ring buffer
   2  * Created: Sat Oct  9 16:19:47 1993
   3  * Revised: Thu Oct 28 21:52:17 1993 by faith@cs.unc.edu
   4  * Copyright 1993 Theodore Ts'o (tytso@athena.mit.edu)
   5  * This program comes with ABSOLUTELY NO WARRANTY.
   6  * Modifications by Rick Sladkey (jrs@world.std.com)
   7  * Larger buffersize 3 June 1998 by Nicolai Langfeldt, based on a patch
   8  * by Peeter Joot.  This was also suggested by John Hudson.
   9  * 1999-02-22 Arkadiusz Mi¶kiewicz <misiek@pld.ORG.PL>
  10  * - added Native Language Support
  11  *
  12  */
  13
  14 #include <linux/unistd.h>
  15 #include <stdio.h>
  16 #include <getopt.h>
  17 #include <stdlib.h>
  18 #include "nls.h"
  19
  20 #if __GNU_LIBRARY__ < 5
  21
  22 #ifndef __alpha__
  23 # define __NR_klogctl __NR_syslog
  24   static inline _syscall3(int, klogctl, int, type, char *, b, int, len);
  25 #else /* __alpha__ */
  26 #define klogctl syslog
  27 #endif
  28
  29 #else
  30 # include <sys/klog.h>
  31 #endif
  32
  33 static char *progname;
  34
  35 static void
  36 usage(void) {
  37    fprintf( stderr, _("Usage: %s [-c] [-n level] [-s bufsize]\n"), progname );
  38 }
  39
  40 int
  41 main( int argc, char *argv[] ) {
  42    char *buf;
  43    int  bufsize = 16392;
  44    int  i;
  45    int  n;
  46    int  c;
  47    int  level = 0;
  48    int  lastc;
  49    int  cmd = 3;
  50
  51    setlocale(LC_ALL, "");
  52    bindtextdomain(PACKAGE, LOCALEDIR);
  53    textdomain(PACKAGE);
  54
  55    progname = argv[0];
  56    while ((c = getopt( argc, argv, "cn:s:" )) != -1) {
  57       switch (c) {
  58       case 'c':
  59          cmd = 4;
  60          break;
  61       case 'n':
  62          cmd = 8;
  63          level = atoi(optarg);
  64          break;
  65       case 's':
  66         bufsize = atoi(optarg);
  67         break;
  68       case '?':
  69       default:
  70          usage();
  71          exit(1);
  72       }
  73    }
  74    argc -= optind;
  75    argv += optind;
  76
  77    if (argc > 1) {
  78       usage();
  79       exit(1);
  80    }
  81
  82    if (cmd == 8) {
  83       n = klogctl( cmd, NULL, level );
  84       if (n < 0) {
  85          perror( "klogctl" );
  86          exit( 1 );
  87       }
  88       exit( 0 );
  89    }
  90
  91    if (bufsize < 4096) bufsize = 4096;
  92    buf = (char*)malloc(bufsize);
  93    n = klogctl( cmd, buf, bufsize );
  94    if (n < 0) {
  95       perror( "klogctl" );
  96       exit( 1 );
  97    }
  98
  99    lastc = '\n';
 100    for (i = 0; i < n; i++) {
 101       if ((i == 0 || buf[i - 1] == '\n') && buf[i] == '<') {
 102          i++;
 103          while (buf[i] >= '0' && buf[i] <= '9')
 104             i++;
 105          if (buf[i] == '>')
 106             i++;
 107       }
 108       lastc = buf[i];
 109       putchar( lastc );
 110    }
 111    if (lastc != '\n')
 112       putchar( '\n' );
 113    return 0;
 114 }